1,584 research outputs found
Flux of Primordial Monopoles
We discuss how in supersymmetric models with D and F-flat directions, a
primordial monopole flux of order 10^{-16} - 10^{-18} cm^{-2} sec^{-1} sr^{-1}
can coexist with the observed baryon asymmetry. A modified Affleck-Dine
scenario yields the desired asymmetry if the monopoles are superheavy (~
10^{13}-10^{18} GeV). For lighter monopoles with masses ~ 10^{9}-10^{12} GeV,
the baryon asymmetry can arise via TeV scale leptogenesis.Comment: 17 pages, 4 figures, revtex
Inflation in Supersymmetric SU(5)
We analyze the adjoint field inflation in supersymmetric (SUSY) SU(5) model.
In minimal SUSY SU(5) hybrid inflation monopoles are produced at the end of
inflation. We therefore explore the non-minimal model of inflation based on
SUSY SU(5), like shifted hybrid, which provides a natural solution for the
monopole problem. We find that the supergravity corrections with non-minimal
Kahler potential are crucial to realize the central value of the scalar
spectral index n_s ~ 0.96 consistent with the seven year WMAP data. The tensor
to scalar ratio r is quite small, taking on values r < 10^{-5}. Due to
R-symmetry massless SU(3) octet and SU(2) triplet Higgs bosons are present and
could spoil for gauge coupling unification. To keep gauge coupling unification
intact, light vector-like particles are added which are expected to be observed
at LHC.Comment: 16 page
Some Properties of Domain Wall Solution in the Randall-Sundrum Model
Properties of the domain wall (kink) solution in the 5 dimensional
Randall-Sundrum model are examined both {\it analytically} and {\it
numerically}. The configuration is derived by the bulk Higgs mechanism. We
focus on 1) the convergence property of the solution, 2) the stableness of the
solution, 3) the non-singular property of the Riemann curvature, 4) the
behaviours of the warp factor and the Higgs field. It is found that the bulk
curvature changes the sign around the surface of the wall. We also present some
{\it exact} solutions for two simple cases: a) the no potential case, b) the
cosmological term dominated case. Both solutions have the (naked) curvature
singularity. We can regard the domain wall solution as a singularity resolution
of the exact solutions.Comment: Typographical error correction for publication. 16 pages, 4 figure
Decomposition of color wavelet with higher order statistical texture and convolutional neural network features set based classification of colorectal polyps from video endoscopy
Gastrointestinal cancer is one of the leading causes of death across the world. The gastrointestinal polyps are considered as the precursors of developing this malignant cancer. In order to condense the probability of cancer, early detection and removal of colorectal polyps can be cogitated. The most used diagnostic modality for colorectal polyps is video endoscopy. But the accuracy of diagnosis mostly depends on doctors' experience that is crucial to detect polyps in many cases. Computer-aided polyp detection is promising to reduce the miss detection rate of the polyp and thus improve the accuracy of diagnosis results. The proposed method first detects polyp and non-polyp then illustrates an automatic polyp classification technique from endoscopic video through color wavelet with higher-order statistical texture feature and Convolutional Neural Network (CNN). Gray Level Run Length Matrix (GLRLM) is used for higher-order statistical texture features of different directions (Ɵ = 0o, 45o, 90o, 135o). The features are fed into a linear support vector machine (SVM) to train the classifier. The experimental result demonstrates that the proposed approach is auspicious and operative with residual network architecture, which triumphs the best performance of accuracy, sensitivity, and specificity of 98.83%, 97.87%, and 99.13% respectively for classification of colorectal polyps on standard public endoscopic video databases
Saprophytic colonization of the bark by Neofusicoccum species mediates subsequent infection of grapevines through wounds
Botryosphaeriaceae species infect grapevines via wounds. A previous study isolated Botryosphaeriaceae at higher frequencies from the bark than the underlying wood of asymptomatic grapevines canes from vineyards,suggesting they were latent on surface tissues. This study investigated the colonization of the bark as a saprophytic link to infection of the underlying wood. The bark of trunks of Sauvignon blanc and Pinot noir potted vines were inoculated by spraying an area of 3 cm length with ~1 mL of a Neofusicoccum luteum or N. parvum conidial suspensions (10⁴/mL). Control vines were inoculated with sterile water. After 1 hour (T1), 2 days (T2) or 7 days (T3) a cut was made in the bark and through to the wood 1 cm above the inoculation area using a sterile scalpel. After 24 h, isolations were carried out from surface sterilized bark and wood. Infection incidence did not differ significantly between species or grapevine cultivar. Infection incidence of the bark was 100% and associated wood of the central inoculated section was 76.3%, 83.3% and 90.2% for T1, T2 and T3, respectively indicating bark infection progressed rapidly into the adjacent wood. Infection of bark and wood 1 cm above the inoculation point increased with incubation time, being 25% for bark and wood at T1 and 71% and 67% for bark and wood, respectively at T3. Infection of the bark and wood 1 cm below the inoculated area was 0%. This study showed that the pathogens remained latent in the bark and, when the cane was wounded, that the pathogen progressed towards the wound. Fluorescent microscopic observations of bark and underlying wood sections of shoots inoculated onto the bark, but without wounding, showed germinating conidia and mycelium in the bark near lenticels, and mycelia in the underlying wood, indicating that the pathogens had entered through lenticels
Quantum illumination using polarization-path entangled single photons for low reflectivity object detection in noisy background
Detecting object with low reflectivity embedded within a noisy background is
a challenging task. Quantum correlations between pairs of quantum states of
light, though are highly sensitive to background noise and losses, offer
advantages over traditional illumination methods. Instead of using correlated
photon pairs which are sensitive, we experimentally demonstrate the advantage
of using heralded single-photons entangled in polarization and path degree of
freedom for quantum illumination. In the study, the object of different
reflectivity is placed along the path of the signal in a variable thermal
background before taking the joint measurements and calculating the quantum
correlations. We show the significant advantage of using non-interferometric
measurements along the multiple paths for single photon to isolate the signal
from the background noise and outperform in detecting and ranging the low
reflectivity objects even when the signal-to-noise ratio is as low as 0.03.
Decrease in visibility of polarization along the signal path also results in
similar observations. This will have direct relevance to the development of
single-photon based quantum LiDAR and quantum imaging.Comment: 8 pages and 6 figure
Neutrino Democracy, Fermion Mass Hierarchies And Proton Decay From 5D SU(5)
The explanation of various observed phenomena such as large angle neutrino
oscillations, hierarchies of charged fermion masses and CKM mixings, and
apparent baryon number conservation may have a common origin. We show how this
could occur in 5D SUSY SU(5) supplemented by a flavor symmetry
and additional matter supermultiplets called 'copies'. In addition, the proton
decays into , with an estimated lifetime of order
yrs. Other decay channels include and with comparable rates. We
also expect that BRBR
Second-order correlations and purity of unheralded single photons from spontaneous parametric down-conversion
Various quantum technology applications require high-purity single photons
with high generation rate. Although different methods are employed to generate
such photons, heralded single photons from spontaneous parametric
down-conversion (SPDC) is the most commonly used approach. Photon generation
rate from the heralded single-photon sources are limited by the efficiency of
the detectors to record coincidence detection of the photon pairs which are
lower than the single-photon counts recorded separately on each detector. In
this paper we present a revised expression to calculate second-order temporal
correlation function, for any fixed time window (bin) and report the
experimental characterization of purity of unheralded and heralded single
photons from the SPDC process. With an appropriate choice of time bin for a
given pump power, without heralding we show that higher rate of single photons
with can be generated with very high probability.Comment: 7 pages, 6 figure
Antimicrobial potentials of Eclipta alba by disc diffusion method
This study was conducted to evaluate the antimicrobial potentials of methanol, petroleum ether, dichloromethane, ethyl acetate, butanol and water extracted samples from the aerial parts of Eclipta alba against nine microbial species. The antimicrobial (antibacterial and antifungal) susceptibility was screened by disc diffusion assay. The tested microbial species were Bacillus cereus, Bacillus subtilis, Candida albicans, Erwinia carotovora, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi and Staphylococcus aureus. The extracts were applied in different concentrations of 1, 2 and 3 mg disc-1. Analysis of the data revealed that all the six extracts from E. alba showed different ranges of antimicrobial activities. Butanol fraction showed inhibitory activities against all the nine microbial species. Ethyl acetate fraction showed inhibitory effects against all the tested microbial species except B. cereus and S. typhi. Petroleum ether, dichloromethane, methanol and water extracted samples had varying levels of inhibitions against some of these microorganisms. The most resistant microbial strain was S. typhi and was not controlled by petroleum ether, dichloromethane, methanol and water extracted samples. The most susceptible Gram positive bacterium was B. subtilis and was inhibited by all the six extracts from E. alba while the most resistant Gram positive bacterium was B. cereus. E. carotovora was the most susceptible Gram negative bacterium while S. typhi and E. coli were highly resistant among the Gram negative bacteria.Key words: Antimicrobial, potential, Eclipta alba, disc diffusion
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