408 research outputs found
Higher order two-mode and multi-mode entanglement in Raman processes
The existence of higher order entanglement in the stimulated and spontaneous
Raman processes is established using the perturbative solutions of the
Heisenberg equations of motion for various field modes that are obtained using
the Sen-Mandal technique and a fully quantum mechanical Hamiltonian that
describes the stimulated and spontaneous Raman processes. Specifically, the
perturbative Sen-Mandal solutions are exploited here to show the signature of
the higher order two-mode and multi-mode entanglement. In some special cases,
we have also observed higher order entanglement in the partially spontaneous
Raman processes. Further, it is shown that the depth of the nonclassicality
indicators (parameters) can be manipulated by the specific choice of coupling
constants, and it is observed that the depth of nonclassicality parameters
increases with the order.Comment: 9 pages, 5 figures. arXiv admin note: text overlap with
arXiv:1301.028
Modified scaling in -essence model in interacting dark energy - dark matter scenario
It has been shown by \textit{Scherrer and Putter et.al} that, when dynamics
of dark energy is driven by a homogeneous essence scalar field , with
a Lagrangian of the form with a constant potential and , one
obtains a scaling relation , where is a constant and
is the FRW scale factor of the universe. The separate energy conservation
in the dark energy sector and the constancy of essence potential are
instrumental in obtaining such a scaling. In this paper, we have shown that
even when considering time-dependent interactions between dark energy and dark
matter, the constancy of essence potential may lead to a modified form of
scaling. We have obtained such a scaling relation for a particular class of
parametrisation of the source term occurring in the continuity equation of dark
energy and dark matter in the interacting scenario. We used inputs from the JLA
analysis of luminosity distance and redshift data from Supernova Ia
observations, to obtain the modified form of the scaling.Comment: 21 pages and 6 figures. This version has been accepted for
publication in European Physical Journal Plu
Indolicidin Targets Duplex DNA: Structural and Mechanistic Insight through a Combination of Spectroscopy and Microscopy
Indolicidin (IR13), a 13‐residue antimicrobial peptide from the cathelicidin family, is known to exhibit a broad spectrum of antimicrobial activity against various microorganisms. This peptide inhibits bacterial DNA synthesis resulting in cell filamentation. However, the precise mechanism remains unclear and requires further investigation. The central PWWP motif of IR13 provides a unique structural element that can wrap around, and thus stabilize, duplex B‐type DNA structures. Replacements of the central Trp‐Trp pair with Ala‐Ala, His‐His, or Phe‐Phe residues in the PxxP motif significantly affects the ability of the peptide to stabilize duplex DNA. Results of microscopy studies in conjunction with spectroscopic data confirm that the DNA duplex is stabilized by IR13, thereby inhibiting DNA replication and transcription. In this study we provide high‐resolution structural information on the interaction between indolicidin and DNA, which will be beneficial for the design of novel therapeutic antibiotics based on peptide scaffolds. That′s a wrap! The PWWP short peptide derived from indolicidin provides a unique structural element that stabilizes the DNA duplex. Substitution of Trp residues in PWWP with Ala, His, or Phe significantly destabilizes the DNA duplex structure, thereby establishing a strong correlation between the surface area of the residues (decreasing order: Ala<His≤Phe<Trp) present between the PxxP domain and DNA stabilization.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108345/1/cmdc_201402215_sm_miscellaneous_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/108345/2/2052_ftp.pd
Investigating the accelerated expansion of the Universe through updated constraints on viable models within the metric formalism
Modified theories of gravity encompass a class of -models that seek to
elucidate the observed late time accelerated expansion of the universe. In this
study, we examine a set of viable models (Hu-Sawicki: two cases,
Satrobinsky, Tsujikawa, exponential and arcTanh models) in metric formalism,
using recent cosmological data sets: type Ia supernovae data, cosmic
chronometer observations, baryonic acoustic oscillations data, data from
H\textsc{ii} starburst galaxies, and local measurements of the Hubble parameter
. The model parameters are constrained using a Bayesian analysis with the
Monte Carlo Markov Chain method. We employ statistical tools such as the Akaike
Information Criterion, Bayesian Information Criterion, and reduced chi-square
statistics to conduct a comparative investigation of these models. We determine
the transition redshift, the evolution of total equation-of-state (EoS)
parameter, and the EoS for the component responsible for current accelerated
expansion to characterize the expansion's evolution. Taking into account the
``Hubble tension," we perform the study with and without a Gaussian prior for
from local measurements. Our findings are as follows: (i) in many cases
the models are strongly favored over the standard CDM model,
(ii) the deviation parameter () significantly deviates from zero in several
cases, (iii) the inclusion of local not only increases the fitted value
of (as expected) but also affects the gap between predictions of
models and the CDM model, and (iv) the relevant quantities
characterizing the (accelerated) expansion of the universe obtained in our
models are consistent with those obtained in a model-independent way by others.
Our investigation and results present a compelling case for pursuing further
research on models with future observations to come
A green process for chlorine-free benzaldehyde from the solvent-free oxidation of benzyl alcohol with molecular oxygen over a supported nano-size gold catalyst
Benzyl alcohol is oxidized selectively to benzaldehyde with high yield, with a little formation of benzylbenzoate, by molecular oxygen over a reusable nano-size gold catalyst supported on U3O8, MgO, Al2O3 or ZrO2 in the absence of any solvent
Dark matter halo occupation: environment and clustering
We use a large dark matter simulation of a LambdaCDM model to investigate the
clustering and environmental dependence of the number of substructures in a
halo. Focusing on redshift z=1, we find that the halo occupation distribution
is sensitive at the tens of percent level to the surrounding density and to a
lesser extent to asymmetry of the surrounding density distribution. We compute
the autocorrelation function of halos as a function of occupation, building on
the finding of Wechsler et al. (2006) and Gao and White (2007) that halos (at
fixed mass) with more substructure are more clustered. We compute the relative
bias as a function of occupation number at fixed mass, finding a strong
relationship. At fixed mass, halos in the top 5% of occupation can have an
autocorrelation function ~ 1.5-2 times higher than the mean. We also compute
the bias as a function of halo mass, for fixed halo occupation. We find that
for group and cluster sized halos, when the number of subhalos is held fixed,
there is a strong anticorrelation between bias and halo mass. Such a
relationship represents an additional challenge to the halo model.Comment: 13 pages, 10 figures, MNRAS submitte
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