Aneeshkumar, B; Pramod, Gopinath; Jayan,Thomas; Vallabhan, C P G; Nampoori, V P N; Radhakrishnan, P(Elsevier, June , 2004)
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Abstract:
The nanosecond optical limiting characteristics of sandwich-type neodymium diphthalocyanine in a co-polymer matrix of polymethyl methacrylate (PMMA) and methyl-2-cyanoacrylate have been studied for the first time. The measurements were performed using 9 ns laser pulses generated from a frequency-doubled Nd:YAG laser at 532 nm wavelength. The optical limiting performance of neodymium diphthalocyanine in co-polymer host was studied at different linear transmission. Laser damage threshold was also measured for the doped and undoped co-polymer samples. The optical limiting response is attributed to reverse saturable absorption which is due to excited-state absorption.
Anantharaman, M R; Sethulakshmi, N; Al-Omari, I A; Suresh, K G(AIP Publishing, March 5, 2014)
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Abstract:
Nearly half of lanthanum sites in lanthanum manganites were substituted with monovalent
ion-sodium and the compound possessed distorted orthorhombic structure. Ferromagnetic ordering
at 300K and the magnetic isotherms at different temperature ranges were analyzed for estimating
magnetic entropy variation. Magnetic entropy change of 1.5 J kg 1 K 1 was observed near 300 K.
An appreciable magnetocaloric effect was also observed for a wide range of temperatures near
300K for small magnetic field variation. Heat capacity was measured for temperatures lower than
300K and the adiabatic temperature change increases with increase in temperature with a
maximum of 0.62K at 280 K
Mohammed Yusuff, K K; Leeju, P; Arun,V; Manju, Sebastian; Varsha, Gopalakrishnan; Digna, Varghese(Crystallography Journals,Acta Crystallographica Section E ,Structure Reports, July 15, 2009)
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Abstract:
In the title molecule, C16H11N5, the mean planes of the
quinoxaline and indazole fragments form a dihedral angle of
10.62 (5). In the crystal, weak intermolecular N—H..........N
hydrogen bonds link the molecules into zigzag chains
extending in the [001] direction. The crystal packing also
exhibits pye interactions [centroid–centroid distances of
3.7080 (2) and 3.8220 (5) A ˚ ], which form stacks of the
molecules parallel to the a axis
Dakshinamurti,K; Paulose,C S; Siow,Y L(Department of Biotechnology, 1985)
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Abstract:
Pyridoxal 5'-phosphate (PLP) is the major coenzymatic
form of pyridoxine. There are over one hundred known pyridoxal
5'-phosphate-dependent reactions, most of which are
involved in the metabolism of various amino acids . Pyridoxamine
5'-phosphate can function in aminotransf erase reactions
by the cyclic regeneration of the two active phosphate
forms. Pyridoxal 5'-phosphate-dependent reactions studied
in the nervous system are involved in the catabolism of various
amino acids. The putative neurotransmitters , dopamine,
norepinephrine , serotonin , histamine , aminobutyric acid
and taurine , as well as the sphingoiipids and poly amines are
synthesized by PLP-dependent enzymes. Of these enzymes,
three ( glutamic acid decarboxylase , 5-hydroxytryptophan decarboxylase
and crnithine decarboxylase) seem to have crucial
roles (Fig. '). The clinical effects of pyridoxine deficiency
can be explained on the basis of the known decreases
in the activities of these enzymes
Dakshinamurti,K; Paulose,C S; Viswanathan,M; Siow,Y L(Department of Biotechnology, 1988)
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Abstract:
Veuruenducrim lri v j p .rim,
deficienc:v. NEUROSCI BIOBEHAV REV 12(3/4) 189-193. 1988.- Dihydroxyphenylalanine decarboxvlase and
5-hydroxytryptophan decarboxvlase respectively have high and low affinities for pyridoxal phosphate. In the pyridoxinedeficient
animal. hypothalamic serotonin content is significantly reduced without any change in catecholamine levels.
Hypothalamic neurotransmitters affect the hvpothalamo-pituitary-end organ axes. Specifically, the decrease in hypothalamic
serotonin in the pyridoxine-deficient rat results in tertiary hypothyroidism. In addition. pineal function is affected in
deficient animals due to decreased synthesis of melatonin.
Paulose,C S; Amee,Krishnakumar; Anu, Joseph(Department of Biotechnology, 2007)
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Abstract:
Neuroscience is the study of'tbe ne rvous system , including the i - ; . in, spinal
cord and peripheral nerves . Neurons are the basic cells of the brain and
nervous system which exerts its functional role through various
neurotransmitters and receptor systems . The activity of a nen ren depends
on the balance between the number of excitatory and inhibito r y processes
affecting it, both processes occurring individually and sin ,tlte-' ,ieously. The
functional bal,ince of different neurotransmitters such as Acct >>lcholine
(Ach), Dopamine (DA), Serotonin (5-1-17), Nor epinepbri,te (N.1 j,
Epinephrine (LPI), Glutamate and Gamma amino butyric acid (GA BA)
regulates the growth , division and other vital functions ofa normal cell /
organisin (Sudha, 1 998). The micro-environ ; nertt of the cell is controlled
/ the macro-environment that surrounds the individual. Any change in
the cell environment causes imbalance in cell homeostasis and f,ntction.
Pollution is a significant cause of imbalance caused iii the inacYcenvironment.
Interaction with polluted environments can have an adverse
impact on the health of humans. The alarming rise in enviromilmieil
cont.iniin :rtion has been linked to rises in levels of pesticides, ndltstr al
effluents, domestic Waste, car exhausts and other anthropogenic activities.
Persistent exposures to contaminant cause a negative imp,-, on brain
health and development . Pollution also causes a change in the
neurotransmitters and their receptor function leading to earl.;' recurrence
of neurodcge,terative disorders such as flypoxia , Alzbeimers's and
Huntington 's disease early in life.
Paulose,C S; Amee,Krishnakumar; Anu, Joseph(Department of Biotechnology, October 25, 2006)
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Abstract:
The recent developments in neurobiology have rendered new prominence
and potential to study about the structure and function of brain and related disorders.
Human behaviour is the net result of neural control of the communication between
brain cells. Neurotransmitters are chemicals that are used to relay, amplify and
modulate electrical signals between neurons and/or another cell. It mediates rapid
intercellular communication through the nervous system by interacting with cell
surface receptors. These receptors often trigger second messenger signaling pathways
that regulate the activity of ion channels. The functional balance of different
neurotransmitters such as Acetylcholine (Ach), Dopamine (DA), Serotonin (5-HT),
Norepinephrine (NE), Epinephrine (EPI), Glutamate and Gamma amino butyric acid
(GABA) regulates the growth, division and other vital functions of a normal cell /
organism (Sudha, 1998). Any change in neurotransmitters' functional balance will
result in the failure of cell function and may lead to the occurrence of diseases.
Abnormalities in the production or functioning of neurotransmitters have been
implicated in a number of neurological disorders like Schizophrenia, Alzheimer's,
Epilepsy, Depression and Parkinson's disease. Changes in central and peripheral
neuronal signaling system is also noted in diabetes, cancer, cell proliferation,
alcoholism and aging. Elucidation of neurotransmitters receptor interaction pathways
and gene expression regulation by second messengers and transcriptional factors
in health and disease conditions can lead to new small molecules for development
of therapeutic agents to improve neurological disease conditions. Increased
awareness of the global effects of neurological disorders should help health care
planners and the neurological community set appropriate priorities in research,
prevention, and management of these diseases.
Supriyo,Dey; Aanandan,C K; Mohanan, P; K G Nair(Microwave and Optical Technology Letters, September , 1994)
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Abstract:
A simple technique to improve the impedance bandwidth of a circular
microstrip patch antenna using two sectorial slots is proposed. Using this
design more than 5% impedance bandwidth is obtained. The added
advantage of this new antenna is that it can be fed by a 50- microstrip line
Aanandan,C K; Mohanan, P; Supriyo,Dey; K G Nair(Department of Electronics, 1994)
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Abstract:
A simple technique to improve the impedance bandwidth of a circular
microstrip patch antenna using two sectorial slots is proposed. Using this
design more than 5% impedance bandwidth is obtained. The added
advantage of this new antenna is that it can be fed by a 50 microstrip
line.
Manju,Paulson; Sona,Kundukulam O; Aanandan,C K; Mohanan, P(Microwave and Optical Technology Letters, June 5, 2001)
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Abstract:
A new compact dual-band, dual-polarized microstrip antenna
is presented. 7'iris antenna resonates at two frequencies with
different polarizations: a linearly polarized one for terrestrial
communication, and a circularly polarized one for satellite mobile
communication. This antenna also provides an area reduction of 70%
compared to a standard rectangular patch antenna
George,J; Deepukumar,M; Aanandan,C K; Mohanan, P; K G Nair(Department of Electronics, March , 1996)
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Abstract:
A new microstrip antenna geometry with considerable reduction
in size, with similar radiation characteristics to those of an
equivalent rectangular patch antenna is proposed. A relationship
has been suggested for fmding out the resonant frequency of the
new geometry, and its validity has been established by the
experimental results. Without increasing the aperture area, this
geometry also offers a facility for considerably reducing the
resonant frequency compared to conventional patches.
Sebastian, Mathew; Joe, Jacob; Joseph, V P; Bijukumar, S; Raveendranath, U; Mathew, K T(John Wiley & Sons, March 5, 1999)
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Abstract:
This paper presents the design of a new type of corner reflector (CR) antenna and the experimental investigation of its radiation characteristics. The design involves the addition of planar parallel periodic strips to the two sides of a CR antenna. The position, angular orientation, and number of strips have a notable effect on the H-plane radiation characteristics of the antenna. Certain configurations of the new antenna are capable of producing very sharp axial beams with gain on the order of 5 dB over the square corner reflector antenna. A configuration that can provide symmetric twin beams with enhanced gain and reduced half-power beam width (HPBW) is also presented.
Tessamma, Thomas; Deepa, Sankar(Society for Imaging Informatics in Medicine, October , 2010)
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Abstract:
In this paper, a novel fast method for modeling mammograms
by deterministic fractal coding approach to detect
the presence of microcalcifications, which are early
signs of breast cancer, is presented. The modeled
mammogram obtained using fractal encoding method is
visually similar to the original image containing microcalcifications,
and therefore, when it is taken out from
the original mammogram, the presence of microcalcifications
can be enhanced. The limitation of fractal image
modeling is the tremendous time required for encoding.
In the present work, instead of searching for a matching
domain in the entire domain pool of the image, three
methods based on mean and variance, dynamic range of
the image blocks, and mass center features are used.
This reduced the encoding time by a factor of 3, 89, and
13, respectively, in the three methods with respect to
the conventional fractal image coding method with quad
tree partitioning. The mammograms obtained from The
Mammographic Image Analysis Society database
(ground truth available) gave a total detection score of
87.6%, 87.6%, 90.5%, and 87.6%, for the conventional
and the proposed three methods, respectively.
Description:
Journal of Digital Imaging, Vol 23, No 5 (October), 2010: pp 538-546
Poulose Jacob,K; Sheena, Mathew(IEEE, December 11, 2005)
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Abstract:
A new fast stream cipher, MAJE4 is designed and
developed with a variable key size of 128-bit or 256-bit. The
randomness property of the stream cipher is analysed by using
the statistical tests. The performance evaluation of the stream
cipher is done in comparison with another fast stream cipher
called JEROBOAM. The focus is to generate a long
unpredictable key stream with better performance, which can
be used for cryptographic applications.
Tessamma, Thomas; Deepa, J(The International Institute for Science, Technology and Education (IISTE), 2013)
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Abstract:
As the technologies for the fabrication of high quality microarray advances rapidly, quantification of
microarray data becomes a major task. Gridding is the first step in the analysis of microarray images for
locating the subarrays and individual spots within each subarray. For accurate gridding of high-density
microarray images, in the presence of contamination and background noise, precise calculation of
parameters is essential. This paper presents an accurate fully automatic gridding method for locating
suarrays and individual spots using the intensity projection profile of the most suitable subimage. The
method is capable of processing the image without any user intervention and does not demand any input
parameters as many other commercial and academic packages. According to results obtained, the accuracy
of our algorithm is between 95-100% for microarray images with coefficient of variation less than two.
Experimental results show that the method is capable of gridding microarray images with irregular spots,
varying surface intensity distribution and with more than 50% contamination
Description:
Computer Engineering and Intelligent Systems,Vol.4, No.1, 2013
New dielectric ceramics with formula BaTi3Nb4, O„ and Ba6Til4Nbz039 have been prepared and characterized. BaTi3Nba017 was densified to 92% of TD after firing at 1310 oC for 4 h. However, Ba6Ti 1 4Nb2O39 fired under optimized conditions (1260 ` C for 4 h) showed only 85% TD together with secondary phase. The crystal system of both of the compositions is orthorhombic
Anantharaman, M R; Joseph, K V; Keer, H V(Springer, May 3, 1997)
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Abstract:
Magnetic materials meant for audio/video recording applications necessitate that
polycrystalline materials be in acicular shape. So preparation of acicular precursors for
magnetic storage materials assumes significance. The employment of aqueous solutions do not
produce needle shape crystallites. Glycerol is one of the complexing media used for the
precipitation of ferrous oxalate dihydrate. An inexpensive method using starch for preparation
of acicular particles is described. The influence of an additive namely Gd on acicularity is also
investigated
Description:
Bull. Mater. Sci., Vol. 20, No. 7, October 1997, pp. 975 980