265 research outputs found
Comparative analysis of the decay in the SM, SUSY and RS model with custodial protection
We comparatively analyze the rare channel in standard model, supersymmetry and Randall-Sundrum model with
custodial protection (RS). Using the parametrization of the matrix elements
entering the low energy effective Hamiltonian in terms of form factors, we
calculate the corresponding differential decay width and lepton
forward-backward asymmetry in these models. We compare the results obtained
with the most recent data from LHCb as well as lattice QCD results on the
considered quantities. It is obtained that the standard model, with the form
factors calculated in light-cone QCD sum rules, can not reproduce some
experimental data on the physical quantities under consideration but the
supersymmetry can do it. The RS model predictions are roughly the same as
the standard model and there are no considerable differences between the
predictions of these two models. In the case of differential decay rate, the
data in the range GeVc GeVc can not be
described by any of the considered models.Comment: 28 Pages, 12 Figures and 3 Table
Analysis of the semileptonic transition in topcolor-assisted technicolor (TC2) model
We comparatively analyze the flavor changing neutral current process of the
in the standard model as well as
topcolor-assisted technicolor model using the form factors calculated via light
cone QCD sum rules in full theory. In particular, we calculate the decay width,
branching ratio and lepton forward-backward asymmetry related to this decay
channel. We compare the results of the topcolor-assisted technicolor model with
those of the standard model and debate how the results of the topcolor-assisted
technicolor model depart from the standard model predictions. We also compare
our results on the differential branching ratio with recent experimental data
provided by CDF and LHCb Collaborations.Comment: 29 Pages, 16 Figures and 8 Table
The distribution and taxonomy of Lissotriton newts in Turkey (Amphibia, Salamandridae)
Two and perhaps three taxa of
Lissotriton
newt occur in Turkey. Their species status is controversial. The
distribution of these taxa and the taxonomic status of each are reviewed and discussed. A database of 128
Turkish
Lissotriton
localities was compiled and species distribution models were constructed. We reiterate
that the presence of
L.
(
v.
)
lantzi
in Turkey is disputed and needs confirmation. The range of
L.
(
v.
)
koss
-
wigi
is restricted to north-western Anatolia – given the small global range of this Turkey endemic, a closer
look at its conservation status is warranted. The distribution of
L. v. schmidtleri
covers western Asiatic
and European Turkey. The findings support an allopatric distribution of the Turkish
Lissotriton
species.
We reflect on the biological significance of previously reported morphological intermediates between
L.
(
v.
)
kosswigi
and
L. v. schmidtleri
in the light of the recent proposal to recognize
kosswigi
at the species
level. The available data are in line with species status for
L.
(
v.
)
lantzi
and
L.
(
v.
)
kosswigi
. Although
L. v.
schmidtleri
is a genetically diverged taxon as well, the extent of gene flow with parapatric European
Lis
-
sotriton
taxa is as yet unknown
First record of facultative paedomorphism in the Kosswig's newt Lissotriton (vulgaris) kosswigi (Freytag, 1955) (Urodela; Salamandridae), endemic to northwestern Turkey
Facultative paedomorphism is regularly observed in salamanders, including newts of the Lissotriton vulgaris group. We document the first record of paedomorphism in L. (v.) kosswigi from a locality near Karasu, in the vicinity of Sakarya, Turkey. We compare measurements of 5 paedomorphic individuals with those of 10 metamorphic individuals from the same population and with measurements taken from the literature. Paedomorphs are on average bigger than metamorphs; intriguingly, the opposite pattern has been observed in the Turkish L. (v.) schmidtlerorum.Animal science
Organ-at-risk sparing with dynamic trajectory radiotherapy for head and neck cancer: comparison with volumetric arc therapy on a publicly available library of cases.
BACKGROUND
Dynamic trajectory radiotherapy (DTRT) extends volumetric modulated arc therapy (VMAT) with dynamic table and collimator rotation during beam-on. The aim of the study is to establish DTRT path-finding strategies, demonstrate deliverability and dosimetric accuracy and compare DTRT to state-of-the-art VMAT for common head and neck (HN) cancer cases.
METHODS
A publicly available library of seven HN cases was created on an anthropomorphic phantom with all relevant organs-at-risk (OARs) delineated. DTRT plans were generated with beam incidences minimizing fractional target/OAR volume overlap and compared to VMAT. Deliverability and dosimetric validation was carried out on the phantom.
RESULTS
DTRT and VMAT had similar target coverage. For three locoregionally advanced oropharyngeal carcinomas and one adenoid cystic carcinoma, mean dose to the contralateral salivary glands, pharynx and oral cavity was reduced by 2.5, 1.7 and 3.1Â Gy respectively on average with DTRT compared to VMAT. For a locally recurrent nasopharyngeal carcinoma, D0.03Â cc to the ipsilateral optic nerve was above tolerance (54.0Â Gy) for VMAT (54.8Â Gy) but within tolerance for DTRT (53.3Â Gy). For a laryngeal carcinoma, DTRT resulted in higher dose than VMAT to the pharynx and brachial plexus but lower dose to the upper oesophagus, thyroid gland and contralateral carotid artery. For a single vocal cord irradiation case, DTRT spared most OARs better than VMAT. All plans were delivered successfully on the phantom and dosimetric validation resulted in gamma passing rates of 93.9% and 95.8% (2%/2Â mm criteria, 10% dose threshold).
CONCLUSIONS
This study provides a proof of principle of DTRT for common HN cases with plans that were deliverable on a C-arm linac with high accuracy. The comparison with VMAT indicates substantial OAR sparing could be achieved
The Near East as a cradle of biodiversity: a phylogeography of banded newts (genus Ommatotriton) reveals extensive inter- and intraspecific genetic differentiation
The banded newt (genus Ommatotriton) is widely distributed in the Near East (Anatolia, Caucasus and the Levant) - an understudied region from the perspective of phylogeography. The genus is polytypic, but the number of species included and the phylogenetic relationships between them are not settled. We sequenced two mitochondrial and two nuclear DNA markers throughout the range of Ommatotriton. For mtDNA we constructed phylogenetic trees, estimated divergence times using fossil calibration, and investigated changes in effective population size with Bayesian skyline plots and mismatch analyses. For nuDNA we constructed phylogenetic trees and haplotype networks. Species trees were constructed for all markers and nuDNA only. Species distribution models were projected on current and Last Glacial Maximum climate layers. We confirm the presence of three Ommatotriton species: O. nesterovi, O. ophryticus and O. vittatus. These species are genetically distinct and their most recent common ancestor was dated at ∼25Ma (Oligocene). No evidence of recent gene flow between species was found. The species show deep intraspecific genetic divergence, represented by geographically structured clades, with crown nodes of species dated ∼8-13Ma (Miocene to Early Quaternary); evidence of long-term in situ evolution and survival in multiple glacial refugia. While a species tree based on nuDNA suggested a sister species relationship between O. vittatus and O. ophryticus, when mtDNA was included, phylogenetic relationships were unresolved, and we refrain from accepting a particular phylogenetic hypothesis at this stage. While species distribution models suggest reduced and fragmented ranges during the Last Glacial Maximum, we found no evidence for strong population bottlenecks. We discuss our results in the light of other phylogeographic studies from the Near East. Our study underlines the important role of the Near East in generating and sustaining biodiversity
Batch and continuous removal of heavy metals from industrial effluents using microbial consortia
Bio-removal of heavy metals, using microbial biomass, increasingly attracting scientific attention due to their significant role in purification of different types of wastewaters making it reusable. Heavy metals were reported to have a significant hazardous effect on human health, and while the conventional methods of removal were found to be insufficient; microbial biosorption was found to be the most suitable alternative. In this work, an immobilized microbial consortium was generated using Statistical Design of Experiment (DOE) as a robust method to screen the efficiency of the microbial isolates in heavy metal removal process. This is the first report of applying Statistical DOE to screen the efficacy of microbial isolates to remove heavy metals instead of screening normal variables. A mixture of bacterial biomass and fungal spores was used both in batch and continuous modes to remove Chromium and Iron ions from industrial effluents. Bakery yeast was applied as a positive control, and all the obtained biosorbent isolates showed more significant efficiency in heavy metal removal. In batch mode, the immobilized biomass was enclosed in a hanged tea bag-like cellulose membrane to facilitate the separation of the biosorbent from the treated solutions, which is one of the main challenges in applying microbial biosorption at large scale. The continuous flow removal was performed using fixed bed mini-bioreactor, and the process was optimized in terms of pH (6) and flow rates (1 ml/min) using Response Surface Methodology. The most potential biosorbent microbes were identified and characterized. The generated microbial consortia and process succeeded in the total removal of Chromium ions and more than half of Iron ions both from standard solutions and industrial effluents
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