Louis, Godfrey; Varughese, George; Santhosh Kumar, A; Philip, J(Indian Academy of Sciences, 2008)
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Abstract:
The double sulfate family (ABSO4), where A and B are alkali metal cations, is the object of great
interest owing to the complexity and richness of its sequence of phase transition induced by temperature
variation. A new sulfate salt characterized by the presence of water molecule in the unit cell with the chemical
formula, Li2Na3(SO4)2⋅6H2O (LSSW), was obtained. The ultrasonic velocity measurement was done with pulse
echo overlap technique [PEO]. All the six second order elastic stiffness constants, C11 = C22, C33, C44 = C55, C12,
C14 and C13 = C23 are reported for the first time. The anisotropy in the elastic properties of the crystal are well
explained by the pictorial representation of the polar plots of phase velocity, slowness, Young’s modulus and
linear compressibility in a–b and a–c planes.
Maya L Pai; Dr. A N Balchand; Dr. K V Pramod(Cochin University of Science and Technology, May 12, 2016)
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Abstract:
ANN based long range forecast of Indian summer monsoon rainfall for
the hydrological regions of India using ocean and atmosphere state
parameters with improved accuracy,Trend analysis of SST, sub surface temperature of Indian Ocean and
that of ISMR.
3. Prediction of extreme rainfall events using ANN.
Anantharaman, M R; Hysen, T; Salim, Al-Harthi; Al-Omari, I A; Geetha, P; Lisha, R; Ramanujan, R V; Sakthi Kumar, D(Elsevier, April 18, 2013)
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Abstract:
Co–Fe–Si based films exhibit high magnetic moments and are highly sought after for applications like soft under layer sinper pendicular recording mediatomagneto-electro-mechanical sensor applications.In this workt he effect of annealing on
s tructural,morphologicaland magnetic propertiesofco–Fe–Si thin films wasinvestigated.compositional analysis using x-rayphotoelectron spectroscopy and secondary ion massspectroscopyrevealedanativeoxidesurfacelayerconsistingofoxidesofco,feandsionthe surface. The morphology of theas deposited films shows mound like structures conformingtothe Volmer–Webergrowthmodel.Nanocrystallisationofamorphous films upon annealing was observed by glancing anglex-raydiffraction and transmission electron microscopy.Theevolutionofmagnetic properties with annealing is explained using the Herzermodel.Vibrating sample magnetometry measurements carried out at various angles from01 to 901 to the applied magnetic field were employed to study the angula rvariation of coercivity.The angular variation fits the modified Kondorsky model. Interestingly,the coercivity evolution with annealing deduced frommagneto-opticalKerreffectstudies indicates areversetrendcomparedtomagetisationobservedinthebulk.Thiscanbeattributedtoa domain wallpinningatnativeoxidelayeronthesurfaceofthin films. Theevolutionofsurfacemagnetic properties iscorrelatedwithmorphologyevolutionprobedusingatomicforcemicroscopy.The morphology aswellasthepresenceofthenativeoxidelayerdictatesthesurfacemagneticproperties and this is corroborated by the apparent difference in the bulk and surface magnetic properties
Riju, C Issac; Harilal, S S; Bindhu, C V; Geetha K, Varier; Nampoori, V P N; Vallabhan, C P G(Elsevier, 1997)
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Abstract:
A laser produced plasma from the multielement solid target YBa2Cu3O7 is generated using 1.06 μm, 9 ns pulses from a Q-switched Nd:YAG laser in air at atmospheric pressure. A time resolved analysis of the profile of the 4554.03 Å resonance line emission from Ba II at various laser power densities has been carried out. It has been found that the line has a profile which is strongly self-reversed. It is also observed that at laser power densities equal to or exceeding 1.6×1011 W cm−2, a third peak begins to develop at the centre of the self-reversed profile and this has been interpreted as due to the anisotropic resonance scattering (fluorescence). The number densities of singly ionized barium ions evaluated from the width of the resonance line as a function of time delay with respect to the beginning of the laser pulse give typical values of the order of 1019 cm−3. The higher ion concentrations existing at smaller time delays are seen to decrease rapidly. The Ba II ions in the ground state resonantly absorb the radiation and this absorption is maximum around 120 ns after the laser pulse.
Bindhu, C V; Harilal, S S; Issac, Riju C; Geetha K, Varier; Nampoori, V P N; Vallabhan, C P G(Pramana, March , 1995)
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Abstract:
Thermal lens signals in solutions of rhodamine B laser dye in methanol are
measured using the dual beam pump-probe technique. The nature of variations of signal
strength with concentration is found to be different for 514 and 488 nm Ar + laser excitations.
However, both the pump wavelengths produce an oscillatory type variation of thermal lens
signal amplitude with the concentration of the dye solution. Probable reasons for this peculiar
behaviour (which is absent in the case of fluorescent intensity) are mentioned.
Poulose Jacob,K; Surekha, Mariam Varghese(2007 ACADEMY PUBLISHER, December 1, 2007)
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Abstract:
This paper discusses our research in developing
a generalized and systematic method for anomaly detection.
The key ideas are to represent normal program behaviour
using system call frequencies and to incorporate
probabilistic techniques for classification to detect
anomalies and intrusions. Using experiments on the
sendmail system call data, we demonstrate that concise and
accurate classifiers can be constructed to detect anomalies.
An overview of the approach that we have implemented is
provided.
Hatha, A A M; Vivekanandhan, G; Savithamani, K; Lakshmanaperumalsamy, P(Elsevier, November 27, 2001)
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Abstract:
A total of 319 strains of Aeromonas hydrophila were isolated from 536 fish and 278 prawns for a 2-year period. All the
strains were tested for resistance to 15 antibiotics and 100% of the strains was resistant to methicillin and rifampicin followed by
bacitracin and novobiocin (99%). Only 3% of the strains exhibited resistance against chloramphenicol. The multiple antibiotic
resistance (MAR) indexing of A. hydrophila strains showed that all of them originated from high-risk sources
Description:
International Journal of Food Microbiology 76 (2002) 165– 168
Hatha, A A M; Divya, P Sukumaran; Srinivasan, Durairaj(Hindawi Publishing Corporation, July 31, 2012)
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Abstract:
This study aimed at detecting the prevalence of antibiotic-resistant serotypes of Escherichia coli in Cochin estuary, India. E. coli
strains were isolated during the period January 2010–December 2011 from five different stations set at Cochin estuary. Water
samples from five different stations in Cochin estuary were collected on a monthly basis for a period of two years. Isolates were
serotyped, antibiogram-phenotyped for twelve antimicrobial agents, and genotyped by polymerase chain reaction for uid gene
that codes for β-D-glucuronidase. These E. coli strains from Cochin estuary were tested against twelve antibiotics to determine
the prevalence of multiple antibiotic resistance among them. The results revealed that more than 53.33% of the isolates were
multiple antibiotic resistant. Thirteen isolates showed resistance to sulphonamides and two of them contained the sul 1 gene.
Class 1 integrons were detected in two E. coli strains which were resistant to more than seven antibiotics. In the present study,
O serotyping, antibiotic sensitivity, and polymerase chain reaction were employed with the purpose of establishing the present
distribution of multiple antibiotic-resistant serotypes, associated with E. coli isolated from different parts of Cochin estuary.
Description:
Interdisciplinary Perspectives on Infectious Diseases
Volume 2012, Article ID 124879, 7 pages
Hatha, A A M; Vivekanandhan, A A; Julie Joice, G; Christol(Elsevier, May 28, 2004)
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Abstract:
Motile aeromonads isolated from the intestines of farm-raised freshwater fish such as Catla catla, Labeo rohita and
Ctenopharyngodon idella have been characterized to species level. Morphological and physiological grouping revealed 61%
Aeromonas hydrophila, 30% Aeromonas caviae, 7% Aeromonas sobria and 2% which remained unidentified. Hemolytic
activity was detected mostly in A. hydrophila, while only half of the A. sobria and A. caviae showed this activity. Antibiotic
resistance patterns of the strains revealed that they had acquired a relatively higher resistance to oxytetracycline, amoxycillin,
ampicillin, novobiocin and polymixin-B, implicating possible use of these antibiotics in the aquaculture systems.
Description:
International Journal of Food Microbiology 98 (2005) 131– 134
Jayaprakash, N S; Bright Singh, I S(School of Environmental Studies, 2005)
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Abstract:
The main objective of the work undertaken here was to develop an appropriate microbial technology to protect the larvae of M.rosenbergii in hatchery from vibriosis. This technology precisely is consisted of a rapid detection system of vibrios and effective antagonistic probiotics for the management of vibrios. The present work was undertaken with the realizations that to stabilize the production process of commercial hatcheries an appropriate, comprehensive and fool proof technology is required primarily for the rapid detection of Vibrio and subsequently for its management. Nine species of Vibrio have been found to be associated with larvae of M. rosenbergii in hatchery. Haemolytic assay of the Vibrio and Aeromonas on prawn blood agar showed that all isolates of V. alginolyticus and Aeromonas sp., from moribund, necrotized larve were haemolytic and the isolates of V.cholerae, V.splendidus II, V.proteolyticus and V.fluvialis from the larvae obtained from apparently healthy larval rearing systems were non-haemolytic.
Hydrolytic enzymes such as lipase, chitinase and gelatinase were widespread amongst the Vibrio and Aeromonas isolates. Dominance of V.alginolyticus among the isolates from necrotic larvae and the failure in isolating them from rearing water strongly suggest that they infect larvae and multiply in the larval body and cause mortality in the hatchery. The observation suggested that the isolate V. alginolyticus was a pathogen to the larvae of M.rosenbergii. To sum up, through this work, nine species of Vibrio and genus Aeromonas associated with M.rosenbergii larval rearing systems could be isolated and segregated based on the haemolytic activity and the antibodies (PA bs) for use in diagnosis or epidemiological studies could be produced, based on a virulent culture of V.alginolyticus. This could possibly replace the conventional biochemical tests for identification. As prophylaxis to vibriosis, four isolates of Micrococcus spp. and an isolate of Pseudomonas sp. could be obtained which could possibly be used as antagonistic probiotics in the larval rearing system of M.rosenbergii.
Bright Singh, I S; Rosamma, Philip; Swapna, Antony P; Valsamma, Joseph(Elsevier, June 21, 2011)
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Abstract:
White Spot Syndrome Virus (WSSV) is the most devastating disease affecting shrimp culture around the
world. Though, considerable progress has been made in the detection and molecular characterization of WSSV
in recent years, information pertaining to immune gene expression in shrimps with respect to WSSV infection
remains limited. In this context, the present study was undertaken to understand the differential expression
of antimicrobial peptide (AMP) genes in the haemocytes of Penaeus monodon in response to WSSV infection
on a time-course basis employing semi-quantitative RT-PCR. The present work analyzes the expression profile
of six AMP genes (ALF, crustin-1, crustin-2, crustin-3, penaeidin-3 and penaeidin-5), eight WSSV genes (DNA
polymerase, endonuclease, immediate early gene, latency related gene, protein kinase, ribonucleotide
reductase, thymidine kinase and VP28) and three control genes (18S rRNA, β-actin and ELF) in P. monodon in
response to WSSV challenge. Penaeidins were found to be up-regulated during early hours of infection and
crustin-3 during late period of infection. However, ALF was found to be up-regulated early to late period of
WSSV infection. The present study suggests that AMPs viz. ALF and crustin-3 play an important role in
antiviral defense in shrimps. WSSV gene transcripts were detected post-challenge day 1 itself and increased
considerably day 5 onwards. Evaluation of the control genes confirmed ELF as the most reliable control gene
followed by 18S rRNA and β-actin for gene expression studies in shrimps. This study indicated the role of
AMPs in the protection of shrimps against viral infection and their possible control through the up-regulation
of AMPs
Antimedian graphs are introduced as the graphs in which for every triple
of vertices there exists a unique vertex x that maximizes the sum of the
distances from x to the vertices of the triple. The Cartesian product of
graphs is antimedian if and only if its factors are antimedian. It is proved
that multiplying a non-antimedian vertex in an antimedian graph yields
a larger antimedian graph. Thin even belts are introduced and proved to
be antimedian. A characterization of antimedian trees is given that leads
to a linear recognition algorithm.
Bright Singh, I S; Anas, A; Paul, S; Jayaprakash, N S; PhIlip, R(Inter-Research, November 9, 2005)
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Abstract:
Chitosan is a biocompatible and biodegradable natural polymer with established
antimicrobial properties against specific microorganisms. The present study demonstrates its
antibacterial activity against 48 isolates of Vibrio species from prawn larval rearing systems. The
antibacterial activity had a positive correlation with the concentration of chitosan. This work opens
up avenues for using chitosan as a prophylactic biopolymer for protecting prawn larvae from
vibriosis.