2,110 research outputs found
Gravitational lens candidates in the E-CDFS
We report ten lens candidates in the E-CDFS from the GEMS survey. Nine of the
systems are new detections and only one of the candidates is a known lens
system. For the most promising five systems including the known lens system, we
present results from preliminary lens mass modelling, which tests if the
candidates are plausible lens systems. Photometric redshifts of the candidate
lens galaxies are obtained from the COMBO-17 galaxy catalog. Stellar masses of
the candidate lens galaxies within the Einstein radius are obtained by using
the -band luminosity and the color-based stellar mass-to-light ratios.
As expected, the lensing masses are found to be larger than the stellar masses
of the candidate lens galaxies. These candidates have similar dark matter
fractions as compared to lenses in SLACS and COSMOS. They also roughly follow
the halo mass-stellar mass relation predicted by the subhalo abundance matching
technique. One of the candidate lens galaxies qualifies as a LIRG and may not
be a true lens because the arc-like feature in the system is likely to be an
active region of star formation in the candidate lens galaxy. Amongst the five
best candidates, one is a confirmed lens system, one is a likely lens system,
two are less likely to be lenses and the status of one of the candidates is
ambiguous. Spectroscopic follow-up of these systems is still required to
confirm lensing and/or for more accurate determination of the lens masses and
mass density profiles.Comment: 12 pages, 5 figures, 3 tables, ApJ accepte
Generalised Decision Level Ensemble Method for Classifying Multi-media Data
In recent decades, multimedia data have been commonly generated and used in various domains, such as in healthcare and social media due to their ability of capturing rich information. But as they are unstructured and separated, how to fuse and integrate multimedia datasets and then learn from them eectively have been a main challenge to machine learning. We present a novel generalised decision level ensemble method (GDLEM) that combines the multimedia datasets at decision level. After extracting features from each of multimedia datasets separately, the method trains models independently on each media dataset and then employs a generalised selection function to choose the appropriate models to construct a heterogeneous ensemble. The selection function is dened as a weighted combination of two criteria: the accuracy of individual models and the diversity among the models. The framework is tested on multimedia data and compared with other heterogeneous ensembles. The results show that the GDLEM is more exible and eective
Phytochemical screening and Gas chromatography-mass spectrometry analysis on Ischaemumpilosum (Kleinex Willd.)
Ischaemumpilosum (Kleinex Willd.) a weed among the grass is reported for ethno-medicinal practices for treatment of various treatments for human and domestic animals. The current work deals with phytochemical analysis in different parts of plants to find out bioactive compounds. The first-time reported results onI. pilosumreveal the significant phytochemicals by using preliminary phytochemical analysis, UV Visible spectral technique, FTIR analysis and GC-MS analysis. The preliminary phytochemical test confirms the presence of alkaloids, anthraquinone, cardiac glycosides, coumarins, flavonoids, glycosides, phenols, reducing sugars, saponins, steroids, tannin and triterpenes in Ischaemumpilosum.UV Visible spectra and FTIR gives the ranges of absorptions and functional group like Carboxylic acids (O-H) at 2956,92 cm-1, Alkanes (O-H) at 2849,89 cm-1, Aldehydes (C=O) at 1735,92 cm-1, Aromatic Rings (C=C) at 1462,95 cm-1, Alkanes (C-H) at 1377,97 cm-1, Esters (C-O) 1166,95 cm-1and Phenyl Ring (C-H) 758,97 cm-1. The GC-MS analysis related twenty-one compounds like Phenol, 4-bis (1,1-dimethylethyl), Pentanoic acid, 5-hydroxy, 2,4-di-t-butylphenyl esters, E-15-Heptadecenal, 1-Hexadecanol, n-Hexadecanoic acid, l (+)-Ascorbic acid 2,6-dihexadecanoate, Palmitic anhydride, Cycloeicosane, Cis-13-Octadecenoic acid and Triacontane from Ischaemumpilosumleaves extract
The nature and origins of the low surface brightness outskirts of massive, central galaxies in Subaru HSC
We explore the stellar mass density and colour profiles of 118 low redshift,
massive, central galaxies, selected to have assembled 90 percent of their
stellar mass 6 Gyr ago, finding evidence of the minor merger activity expected
to be the driver behind the size growth of quiescent galaxies. We use imaging
data in the bands from the Subaru Hyper Suprime-Cam survey and
perform SED fitting to construct spatially well-resolved radial profiles in
colour and stellar mass surface density. Our visual morphological
classification reveals that percent of our sample displays tidal
features, similar to previous studies, percent of the remaining
sample display a diffuse stellar halo and only percent display no
features, down to a limiting 28 mag
arcsec. We find good agreement between the stacked colour profiles of
our sample to those derived from previous studies and an expected smooth,
declining stellar mass surface density profile in the central regions (< 3
R). However, we also see a flattening of the profile ( M kpc) in the outskirts (up to 10
R), which is revealed by our method of specifically targeting
tidal/accretion features. We find similar levels of tidal features and
behaviour in the stellar mass surface density profiles in a younger comparison
sample, however a lack of diffuse haloes. We also apply stacking techniques,
similar to those in previous studies, finding such procedures wash out tidal
features and thereby produces smooth declining profiles. The stellar material
in the outskirts contributes on average M or a few
percent of the total stellar mass and has similar colours to SDSS satellites of
similar stellar mass.Comment: 14 pages, 9 figures, 1 tabl
Isolation, Purification, and Characterization of Fungal Laccase from Pleurotus sp.
Laccases are blue copper oxidases (E.C. 1.10.3.2 benzenediol: oxygen oxidoreductase) that catalyze the one-electron oxidation of phenolics, aromatic amines, and other electron-rich substrates with the concomitant reduction of O2 to H2O. They are currently seen as highly interesting industrial enzymes because of their broad substrate specificity. A positive strain was isolated and characterized as nonspore forming Basidiomycetes Pleurotus sp. Laccase activity was determined using ABTS as substrate. Laccase was purified by ionexchange and gel filtration chromatography. The purified laccase was a monomer showed a molecular mass of 40 ± 1 kDa as estimated by SDS-PAGE and a 72-fold purification with a 22% yield. The optimal pH and temperature were 4.5 and 65°C, respectively. The Km and Vmax values are 250 (mM) and 0.33 (μmol/min), respectively, for ABTS as substrate. Metal ions like CuSO4, BaCl2, MgCl2, FeCl2, ZnCl2 have no effect on purified laccase whereas HgCl2 and MnCl2 moderately decrease enzyme activity. SDS and sodium azide inhibited enzyme activity, whereas Urea, PCMB, DTT, and mercaptoethanol have no effect on enzyme activity. The isolated laccase can be used in development of biosensor for detecting the phenolic compounds from the effluents of paper industries
Fast simulation of a quantum phase transition in an ion-trap realisable unitary map
We demonstrate a method of exploring the quantum critical point of the Ising
universality class using unitary maps that have recently been demonstrated in
ion trap quantum gates. We reverse the idea with which Feynman conceived
quantum computing, and ask whether a realisable simulation corresponds to a
physical system. We proceed to show that a specific simulation (a unitary map)
is physically equivalent to a Hamiltonian that belongs to the same universality
class as the transverse Ising Hamiltonian. We present experimental signatures,
and numerical simulation for these in the six-qubit case.Comment: 12 pages, 6 figure
Canonical Gravity, Diffeomorphisms and Objective Histories
This paper discusses the implementation of diffeomorphism invariance in
purely Hamiltonian formulations of General Relativity. We observe that, if a
constrained Hamiltonian formulation derives from a manifestly covariant
Lagrangian, the diffeomorphism invariance of the Lagrangian results in the
following properties of the constrained Hamiltonian theory: the diffeomorphisms
are generated by constraints on the phase space so that a) The algebra of the
generators reflects the algebra of the diffeomorphism group. b) The Poisson
brackets of the basic fields with the generators reflects the space-time
transformation properties of these basic fields. This suggests that in a purely
Hamiltonian approach the requirement of diffeomorphism invariance should be
interpreted to include b) and not just a) as one might naively suppose. Giving
up b) amounts to giving up objective histories, even at the classical level.
This observation has implications for Loop Quantum Gravity which are spelled
out in a companion paper. We also describe an analogy between canonical gravity
and Relativistic particle dynamics to illustrate our main point.Comment: Latex 16 Pages, no figures, revised in the light of referees'
comments, accepted for publication in Classical and Quantum Gravit
Instabilities in the Nuclear Energy Density Functional
In the field of Energy Density Functionals (EDF) used in nuclear structure
and dynamics, one of the unsolved issues is the stability of the functional.
Numerical issues aside, some EDFs are unstable with respect to particular
perturbations of the nuclear ground-state density. The aim of this contribution
is to raise questions about the origin and nature of these instabilities, the
techniques used to diagnose and prevent them, and the domain of density
functions in which one should expect a nuclear EDF to be stable.Comment: Special issue "Open Problems in Nuclear Structure Theory" of
Jour.Phys.G - accepted. 7 pages, 2 figure
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