Mridula, S; Binu, Paul; Mythili, P; Mohanan, P(Wiley Subscription Services, Inc., A Wiley Company, December , 2010)
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Abstract:
A method for simultaneously enhancing the bandwidth
and reducing the size of microstrip antennas (MSAs) using a modified
ground plane (GP) has been proposed with design formulas. A combshaped
truncated GP is used for this purpose. This method provides an
overall compactness up to 85% for proximity-coupled MSAs in the
frequency range of 900 MHz–5.5 GHz with an improvement inbandwidth up to seven times when compared with the conventional ones
Description:
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 52, No. 12, December 2010
Shynu, S V; Gijo,Augustin; Aanandan,C K; Mohanan, P; Vasudevan, K(Progress In Electromagnetics Research, 2006)
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Abstract:
The design of a compact, single feed, dual frequency
dual polarized and electronically reconfigurable microstrip antenna is
presented in this paper. A square patch loaded with a hexagonal slot
having extended slot arms constitutes the fundamental structure of
the antenna. The tuning of the two resonant frequencies is realized by
varying the effective electrical length of the slot arms by embedding
varactor diodes across the slots. A high tuning range of 34.43%
(1.037–1.394 GHz) and 9.27% (1.359–1.485 GHz) is achieved for the
two operating frequencies respectively, when the bias voltage is varied
from 0 to −30 V. The salient feature of this design is that it uses no
matching networks even though the resonant frequencies are tuned in
a wide range with good matching below −10 dB. The antenna has an
added advantage of size reduction up to 80.11% and 65.69% for the two
operating frequencies compared to conventional rectangular patches.
Prakash,P N; Dr.Ramaiah,D(National Institute for Interdisciplinary Science and Technology,CSIR, December , 2008)
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Abstract:
Development of organic molecules that exhibit selective
interactions with different biomolecules has immense significance
in biochemical and medicinal applications. In this context, our main
objective has been to design a few novel functionaIized molecules
that can selectively bind and recognize nucleotides and DNA in the aqueous medium through non-covalent interactions. Our strategy
was to design novel cycIophane receptor systems based on the
anthracene chromophore linked through different bridging moieties
and spacer groups. It was proposed that such systems would have a
rigid structure with well defined cavity, wherein the aromatic
chromophore can undergo pi-stacking interactions with the guest
molecules. The viologen and imidazolium moieties have been
chosen as bridging units, since such groups, can in principle, could
enhance the solubility of these derivatives in the aqueous medium
as well as stabilize the inclusion complexes through electrostatic
interactions.We synthesized a series of water soluble novel functionalized
cyclophanes and have investigated their interactions with
nucleotides, DNA and oligonucIeotides through photophysical.
chiroptical, electrochemical and NMR techniques. Results indicate
that these systems have favorable photophysical properties and
exhibit selective interactions with ATP, GTP and DNA involving
electrostatic. hydrophobic and pi-stacking interactions inside the
cavity and hence can have potential use as probes in biology.
Akhil, K Nair; Dr.Ramaiah,D(Cochin University Of Science And Technology, October 3, 2013)
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Abstract:
Design and study of molecular receptors capable of mimicking
natural processes has found applications in basic research as well as in
the development of potentially useful technologies. Of the various
receptors reported, the cyclophanes are known to encapsulate guest
molecules in their cavity utilizing various non–covalent interactions
resulting in significant changes in their optical properties. This unique
property of the cyclophanes has been widely exploited for the
development of selective and sensitive probes for a variety of guest
molecules including complex biomolecules. Further, the incorporation of
metal centres into these systems added new possibilities for designing
receptors such as the metallocyclophanes and transition metal
complexes, which can target a large variety of Lewis basic functional
groups that act as selective synthetic receptors.
The ligands that form complexes with the metal ions, and are
capable of further binding to Lewis-basic substrates through open
coordination sites present in various biomolecules are particularly
important as biomolecular receptors. In this context, we synthesized a
few anthracene and acridine based metal complexes and novel
metallocyclophanes and have investigated their photophysical and
biomolecular recognition properties.
Description:
Photosciences and Photonics
Chemical Sciences and Technology Division
CSIR-National Institute for Interdisciplinary Science and
Technology (CSIR-NIIST), Trivandrum
Babita Roslind, Jose; Dr.Mythili, P(Cochin University of Science & Technology, January , 2010)
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Abstract:
Analog-to digital Converters (ADC) have an important impact on the overall performance of signal processing system. This research is to explore efficient techniques for the design of sigma-delta ADC,specially for multi-standard wireless tranceivers. In particular, the aim is to develop novel models and algorithms to address this problem and to implement software tools which are avle to assist the designer's decisions in the system-level exploration phase. To this end, this thesis presents a framework of techniques to design sigma-delta analog to digital converters.A2-2-2 reconfigurable sigma-delta modulator is proposed which can meet the design specifications of the three wireless communication standards namely GSM,WCDMA and WLAN. A sigma-delta modulator design tool is developed using the Graphical User Interface Development Environment (GUIDE) In MATLAB.Genetic Algorithm(GA) based search method is introduced to find the optimum value of the scaling coefficients and to maximize the dynamic range in a sigma-delta modulator.
Description:
School of Engineering, Cochin University of Science and Technology
Hatha, A A M; Reema, Singh; Vinay, Narayan; Patricia, McLenachan; Richard, C. Winkworth; Suparna, Mitra; Peter, J. Lockhart; Lorraine, Berry; William, Aalbersberg; Dhana, Rao(Society for Applied Microbiology and Blackwell Publishing Ltd, March 16, 2012)
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Abstract:
Here we investigate the diversity of pathogenic Vibrio
species in marine environments close to Suva, Fiji.
We use four distinct yet complementary analyses –
biochemical testing, phylogenetic analyses, metagenomic
analyses and molecular typing – to provide
some preliminary insights into the diversity of vibrios
in this region. Taken together our analyses confirmed
the presence of nine Vibrio species, including three
of the most important disease-causing vibrios (i.e.
V. cholerae, V. parahaemolyticus and V. vulnificus), in
Fijian marine environments. Furthermore, since toxigenic
V. parahaemolyticus are present on fish for
consumption we suggest these bacteria represent a
potential public health risk. Our results from Illumina
short read sequencing are encouraging in the context
of microbial profiling and biomonitoring. They
suggest this approach may offer an efficient and costeffective
method for studying the dynamics of microbial
diversity in marine environments over time.
Mathew, K T; Anil, Lonappan; Paul, Benzy; Thimothy, V O; Rajasekaran, C; Vinu, Thomas; Joe, Jacob(Wiley InterScience, January , 2009)
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Abstract:
This article reports a new in vitro bile analysis based on
the measurement of the dielectric properties at microwave frequencies.
The measurements were made using rectangular cavity perturbation
technique at the S-band of microwave frequency with the different samples
of bile obtained from healthy persons as well as from patients. It is
observed that an appreciable change in the dielectric properties of patient’s
samples with the normal healthy samples and these measurements
were in good agreement with clinical analysis. These results prove an
alternative in-vitro method of detecting bile abnormalities based on the
measurement of the dielectric properties of bile samples using microwaves
without surgical procedure.
Sumam, Mary Idicula; Geethu, Miriam Jacob(IEEE, 2012)
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Abstract:
In this paper, moving flock patterns are mined from
spatio- temporal datasets by incorporating a clustering
algorithm. A flock is defined as the set of data that
move together for a certain continuous amount of time.
Finding out moving flock patterns using clustering
algorithms is a potential method to find out frequent
patterns of movement in large trajectory datasets. In
this approach, SPatial clusteRing algoRithm thrOugh
sWarm intelligence (SPARROW) is the clustering
algorithm used. The advantage of using SPARROW
algorithm is that it can effectively discover clusters of
widely varying sizes and shapes from large databases.
Variations of the proposed method are addressed and
also the experimental results show that the problem of
scalability and duplicate pattern formation is
addressed. This method also reduces the number of
patterns produced
Description:
2012 International Conference on Data Science & Engineering (ICDSE)
Bagei, A M; Cetin, A E(IEE Electronics letters,UK, October 24, 2002)
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Abstract:
A method for computer- aided diagnosis of micro calcification clusters
in mammograms images presented . Micro calcification clus.eni which
are an early sign of bread cancer appear as isolated bright spots in
mammograms. Therefore they correspond to local maxima of
the image. The local maxima of the image is lint detected and they
are ranked according to it higher-order statistical test performed over
the sub band domain data
Sunil, Thomas; Dr.Balasundaran, M(Cochin University of Science And Technology, June , 2000)
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Abstract:
Spike disease in sandal is generally diagnosed by the manifestation of
external symptoms. Attempts have been made to detect the diseased plants
by determining the length/breadth ratio of leaves (lyengar, 1961) and
histochemical tests using Mann's stain (Parthasarathi et al., 1966), Dienes'
stain (Ananthapadmanabha et a/., 1973) aniline blue and Hoechst 33258
(Ghosh et a/., 1985, Rangaswamy, 1995). But most of these techniques are
insensitive, indirect detection methods leading to misinterpretation of results.
Moreover, to identify disease resistant sandal trees, highly sensitive
techniques are needed to detect the presence of the pathogen. In sandal
forests, several host plants of sandal like Zizyphus oenop/ea (Fig. 1.3) also
exhibit the yellows type disease symptoms. Immunological and molecular
assays have to be developed to confirm the presence of sandal spike
phytoplasma in such hosts. The major objectives of the present work
includes:In situ detection of sandal spike phytoplasma by epifluorescence
microscopy and scanning electron microscopy.,Purification of sandal spike phytoplasma and production of polyclonal antibodies.,Amino acid and total protein estimation of sandal spike phytoplasma.,Immunological detection of sandal spike phytoplasma.,
Molecular detection of sandal spike phytoplasma.,Screening for phytoplasma in host plants of spike disease affected sandal using immunological and molecular techniques.
Description:
Department of environmental studies, Cochin University of Science And Technology
Chandrasekaran, M; Lailaja, V P(Springer, February 27, 2013)
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Abstract:
Bacillus smithii BTMS 11, isolated from marine
sediment, produced alkaline and thermostable lipase.
The enzyme was purified to homogeneity by ammonium
sulfate precipitation and ion exchange chromatography
which resulted in 0.51 % final yield and a 4.33 fold of
purification. The purified enzyme was found to have a
specific activity of 360 IU/mg protein. SDS-PAGE analyses,
under non-reducing and reducing conditions, yielded a
single band of 45 kDa indicating the single polypeptide
nature of the enzyme and zymogram analysis using methylumbelliferyl
butyrate as substrate confirmed the lipolytic
activity of the protein band. The enzyme was found to have
50 C and pH 8.0 as optimum conditions for maximal
activity. However, the enzyme was active over wide range
of temperatures (30–80 C) and pH (7.0–10.0). Effect of a
number of metal salts, solvents, surfactants, and other
typical enzyme inhibitors on lipase activity was studied to
determine the novel characteristics of the enzyme. More
than 90 % of the enzyme activity was observed even after
3 h of incubation in the presence of commercial detergents
Surf, Sunlight, Ariel, Henko, Tide and Ujala indicating the
detergent compatibility of B. smithii lipase. The enzyme
was also found to be efficient in stain removal from cotton
cloths. Further it was observed that the enzyme could
catalyse ester synthesis between fatty acids of varying
carbon chain lengths and methanol with high preference for
medium to long chain fatty acids showing 70 % of esterification.
Results of the study indicated scope for application
of this marine bacterial lipase in various industries
Description:
World J Microbiol Biotechnol (2013) 29:1349–1360
DOI 10.1007/s11274-013-1298-0
Thomas, Varghese; Dr.Moli,P Koshy(Cochin University Of Science And Technology, April , 2013)
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Abstract:
This research work was to study the level of awareness of consumers
about health insurance concept and market, consumer perceptions about
health insurance providers, schemes and various factors that influence
buying decision of health insurance.
There is need to bring entire age group – high risk and low risk under
health insurance cover. Widening the cover of health insurance calls for indepth
understanding of consumer thinking and extensive marketing efforts
based on that. Hence the study of consumer perceptions and the impact of
different contributing factors on consumer purchase decision assume
significance to the marketer. Understanding the consumer thinking on
health insurance will also be of relevance to governmental/non
governmental agencies, as affordable health care to all is a policy objective
of the government and new schemes are being launched in this area.
Description:
School of Management Studies
Cochin University of Science and Technology
Anantharaman, M R; Sajeev, Sivaraman(IOP Publishing LTD, January 21, 2010)
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Abstract:
The carrier transport mechanism of polyaniline (PA) thin films prepared by radio frequency
plasma polymerization is described in this paper. The mechanism of electrical conduction and
carrier mobility of PA thin films for different temperatures were examined using the
aluminium–PA–aluminium (Al–PA–Al) structure. It is found that the mechanism of carrier
transport in these thin films is space charge limited conduction. J –V studies on an asymmetric
electrode configuration using indium tin oxide (ITO) as the base electrode and Al as the upper
electrode (ITO–PA–Al structure) show a diode-like behaviour with a considerable rectification
ratio
Rajasree, K; Radhakrishnan, P; Nampoori, V P N; Vallabhan, C P G(IOP, 1993)
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Abstract:
A pulsed Nd-YAG laser beam is used to produce a transient refractive index gradient in air adjoining the plane surface of the sample material. This refractive index gradient is probed by a continuous He-Ne laser beam propagating parallel to the sample surface. The observed deflection signals produced by the probe beam exhibit drastic variations when the pump laser energy density crosses the damage threshold for the sample. The measurements are used to estimate the damage threshold for a few polymer samples. The present values are found to be in good agreement with those determined by other methods.