282 research outputs found
Microfaradaic Electrochemical Biosensors for the Study of Anticancer Action of DNA Intercalating Drug: Epirubicin
Toward establishing the presence or absence of horizons in coalescing binaries of compact objects by using their gravitational wave signals
New Black Hole Solutions in Brans-Dicke Theory of Gravity
Existence check of non-trivial, stationary axisymmetric black hole solutions
in Brans-Dicke theory of gravity in different direction from those of Penrose,
Thorne and Dykla, and Hawking is performed. Namely, working directly with the
known explicit spacetime solutions in Brans-Dicke theory, it is found that
non-trivial Kerr-Newman-type black hole solutions different from general
relativistic solutions could occur for the generic Brans-Dicke parameter values
-5/2\leq \omega <-3/2. Finally, issues like whether these new black holes carry
scalar hair and can really arise in nature and if they can, what the associated
physical implications would be are discussed carefully.Comment: 20 pages, no figure, Revtex, version to appear in Phys. Rev.
Convergence despite divergence: Views of academic and community stakeholders about the ethics of community-engaged research
Purpose: Stakeholder engagement and community-engaged research (CEnR) are recognized as approaches necessary to promote health equity. Few studies have examined variations in stakeholder perspectives on research ethics despite the potential for meaningful differences. Our study examines the association between stakeholders' characteristics and their perception of the importance of 15 stakeholder-developed CEnR ethical statements. Design: Quantitative analysis of close-ended Delphi survey. Participants: We recruited a national, non-random, purposive sample of people who were eligible if they endorsed conducting CEnR in public health or biomedical fields. Participants were recruited from publicly available information, professional email distributions, and snowball sampling. Main Outcome Measures: We designed our close-ended Delphi survey from the results of 15 CEnR ethical statements, which were developed from a consensus development workshop with academic and community stakeholders. Results: 259 participants completed the Delphi survey. The results demonstrated that stakeholders' characteristics (affiliation, ethnicity, number of CEnR relationships, and duration of CEnR partnerships) were not associated with their perception of the importance of 15 ethical statements. Conclusions: The strong agreement among stakeholders on these broad, aspirational ethical statements can help guide partnerships toward ethical decisions and actions. Continued research about variability among stakeholders' ethics perspectives is needed to bolster the capacity of CEnR to contribute to health equity
Bianchi Type III Anisotropic Dark Energy Models with Constant Deceleration Parameter
The Bianchi type III dark energy models with constant deceleration parameter
are investigated. The equation of state parameter is found to be time
dependent and its existing range for this model is consistent with the recent
observations of SN Ia data, SN Ia data (with CMBR anisotropy) and galaxy
clustering statistics. The physical aspect of the dark energy models are
discussed.Comment: 12 pages, 2 figures, Accepted version of IJT
Some anisotropic universes in the presence of imperfect fluid coupling with spatial curvature
We consider Bianchi VI spacetime, which also can be reduced to Bianchi types
VI0-V-III-I. We initially consider the most general form of the energy-momentum
tensor which yields anisotropic stress and heat flow. We then derive an
energy-momentum tensor that couples with the spatial curvature in a way so as
to cancel out the terms that arise due to the spatial curvature in the
evolution equations of the Einstein field equations. We obtain exact solutions
for the universes indefinetly expanding with constant mean deceleration
parameter. The solutions are beriefly discussed for each Bianchi type. The
dynamics of the models and fluid are examined briefly, and the models that can
approach to isotropy are determined. We conclude that even if the observed
universe is almost isotropic, this does not necessarily imply the isotropy of
the fluid (e.g., dark energy) affecting the evolution of the universe within
the context of general relativity.Comment: 17 pages, no figures; to appear in International Journal of
Theoretical Physics; in this version (which is more concise) an equation
added, some references updated and adde
Unimodular bimode gravity and the coherent scalar-graviton field as galaxy dark matter
The explicit violation of the general gauge invariance/relativity is adopted
as the origin of dark matter and dark energy of the gravitational nature. The
violation of the local scale invariance alone, with the residual unimodular
one, is considered. Besides the four-volume preserving deformation mode -- the
transverse-tensor graviton -- the metric comprises a compression mode -- the
scalar graviton, or the systolon. A unimodular invariant and general covariant
metric theory of the bimode/scalar-tensor gravity is consistently worked out.
To reduce the primordial ambiguity of the theory a dynamical global symmetry is
imposed, with its subsequent spontaneous breaking revealed. The static
spherically symmetric case in the empty, but possibly for the origin, space is
studied. A three-parameter solution describing a new static space structure --
the dark lacuna -- is constructed. It enjoys the property of gravitational
confinement, with the logarithmic potential of gravitational attraction at the
periphery, and results in the asymptotically flat rotation curves. Comprising a
super-massive dark fracture (a scalar-modified black hole) at the origin
surrounded by a cored dark halo, the dark lacunas are proposed as a prototype
model of galaxies, implying an ultimate account for the distributed
non-gravitational matter and a putative asphericity or rotation.Comment: 38 pages, 10 figures; exposition improved, remarks added, accepted
for publicatio
The exposure of the hybrid detector of the Pierre Auger Observatory
The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays.
It consists of a surface array to measure secondary particles at ground level
and a fluorescence detector to measure the development of air showers in the
atmosphere above the array. The "hybrid" detection mode combines the
information from the two subsystems. We describe the determination of the
hybrid exposure for events observed by the fluorescence telescopes in
coincidence with at least one water-Cherenkov detector of the surface array. A
detailed knowledge of the time dependence of the detection operations is
crucial for an accurate evaluation of the exposure. We discuss the relevance of
monitoring data collected during operations, such as the status of the
fluorescence detector, background light and atmospheric conditions, that are
used in both simulation and reconstruction.Comment: Paper accepted by Astroparticle Physic
Observation of Orbitally Excited B_s Mesons
We report the first observation of two narrow resonances consistent with
states of orbitally excited (L=1) B_s mesons using 1 fb^{-1} of ppbar
collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the
Fermilab Tevatron. We use two-body decays into K^- and B^+ mesons reconstructed
as B^+ \to J/\psi K^+, J/\psi \to \mu^+ \mu^- or B^+ \to \bar{D}^0 \pi^+,
\bar{D}^0 \to K^+ \pi^-. We deduce the masses of the two states to be m(B_{s1})
= 5829.4 +- 0.7 MeV/c^2 and m(B_{s2}^*) = 5839.7 +- 0.7 MeV/c^2.Comment: Version accepted and published by Phys. Rev. Let
Capturing wheat phenotypes at the genome level
Recent technological advances in next-generation sequencing (NGS) technologies have dramatically reduced the cost of DNA sequencing, allowing species with large and complex genomes to be sequenced. Although bread wheat (Triticum aestivum L.) is one of the world’s most important food crops, efficient exploitation of molecular marker-assisted breeding approaches has lagged behind that achieved in other crop species, due to its large polyploid genome. However, an international public–private effort spanning 9 years reported over 65% draft genome of bread wheat in 2014, and finally, after more than a decade culminated in the release of a gold-standard, fully annotated reference wheat-genome assembly in 2018. Shortly thereafter, in 2020, the genome of assemblies of additional 15 global wheat accessions was released. As a result, wheat has now entered into the pan-genomic era, where basic resources can be efficiently exploited. Wheat genotyping with a few hundred markers has been replaced by genotyping arrays, capable of characterizing hundreds of wheat lines, using thousands of markers, providing fast, relatively inexpensive, and reliable data for exploitation in wheat breeding. These advances have opened up new opportunities for marker-assisted selection (MAS) and genomic selection (GS) in wheat. Herein, we review the advances and perspectives in wheat genetics and genomics, with a focus on key traits, including grain yield, yield-related traits, end-use quality, and resistance to biotic and abiotic stresses. We also focus on reported candidate genes cloned and linked to traits of interest. Furthermore, we report on the improvement in the aforementioned quantitative traits, through the use of (i) clustered regularly interspaced short-palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated gene-editing and (ii) positional cloning methods, and of genomic selection. Finally, we examine the utilization of genomics for the next-generation wheat breeding, providing a practical example of using in silico bioinformatics tools that are based on the wheat reference-genome sequence
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