306 research outputs found
Phenomenology of flavorful composite vector bosons in light of anomalies
We analyze the flavor structure of composite vector bosons arising in a model
of vectorlike technicolor, often called hypercolor (HC), with eight flavors
that form a one-family content of HC fermions. Dynamics of the composite vector
bosons, referred to as HC rho in this paper, are formulated together with HC
pions by the hidden local symmetry (HLS), in a way analogous to QCD vector
mesons. Then coupling properties to the standard model (SM) fermions, which
respect the HLS gauge symmetry, are described in a way that couplings of the HC
rhos to the left-handed SM quarks and leptons are given by a well-defined setup
as taking the flavor mixing structures into account. Under the present
scenario, we discuss significant bounds on the model from electroweak precision
tests, flavor physics, and collider physics. We also try to address B anomalies
in processes such as B -> K(*) mu+ mu- and B -> D(*) tau nu, recently reported
by LHCb, Belle, (ATLAS, and CMS in part.) Then we find that the present model
can account for the anomaly in B -> K(*) mu+ mu- consistently with the other
constraints while it predicts no significant deviations in B -> D(*) tau nu
from the SM, which can be examined in the future Belle II experiment. The
former is archived with the form C9 = -C10 of the Wilson coefficients for
effective operators of b -> s mu+ mu-, which has been favored by the recent
experimental data. We also investigate current and future experimental limits
at the Large Hadron Collider (LHC) and see that possible collider signals come
from dijet and ditau, or dimuon resonant searches for the present scenario with
TeV mass range. To conclude, the present b -> s mu+ mu- anomaly is likely to
imply discovery of new vector bosons in the ditau or dimuon channel in the
context of the HC rho model. Our model can be considered as a UV completion of
conventional U(1)' model.Comment: 62 pages, 8 figures, 3 tables, typos modified, published versio
Simultaneous interpretation of and anomalies in terms of chiral-flavorful vectors
We address the presently reported significant flavor anomalies in the Kaon
and meson systems such as the CP violating Kaon decay
() and lepton-flavor universality violation in meson
decays (), by proposing flavorful and chiral vector
bosons as the new physics constitution at around TeV scale. The
chiral-flavorful vectors (CFVs) are introduced as a 63-plet of the global
symmetry, identified as the one-family symmetry for left-handed quarks
and leptons in the standard model (SM) forming the 8-dimensional vector. Thus
the CFVs include massive gluons, vector leptoquarks, and -type bosons,
which are allowed to have flavorful couplings with left-handed quarks and
leptons, and flavor-universal couplings to right-handed ones, where the latter
arises from mixing with the SM gauge bosons. The flavor texture is assumed to
possess a "minimal" structure to be consistent with the current flavor
measurements on the and systems. Among the presently reported
significant flavor anomalies in the Kaon and meson systems
(, ), the first two
and anomalies can simultaneously be
interpreted by the presence of CFVs, the anomaly is predicted
not to survive, due to the approximate flavor symmetry. Remarkably, we
find that as long as both of the and
anomalies persist beyond the SM, the CFVs predict the enhanced and decay rates compared to the SM
values, which will readily be explored by the NA62 and KOTO experiments, and
they will also be explored in new resonance searches at the Large Hadron
Collider.Comment: 52 pages, 14 figures, 1 table, version published in JHE
Single-Shot Global Localization via Graph-Theoretic Correspondence Matching
This paper describes a method of global localization based on graph-theoretic
association of instances between a query and the prior map. The proposed
framework employs correspondence matching based on the maximum clique problem
(MCP). The framework is potentially applicable to other map and/or query
modalities thanks to the graph-based abstraction of the problem, while many of
existing global localization methods rely on a query and the dataset in the
same modality. We implement it with a semantically labeled 3D point cloud map,
and a semantic segmentation image as a query. Leveraging the graph-theoretic
framework, the proposed method realizes global localization exploiting only the
map and the query. The method shows promising results on multiple large-scale
simulated maps of urban scenes
Evaluating contributions of natural language parsers to protein–protein interaction extraction
Motivation: While text mining technologies for biomedical research have gained popularity as a way to take advantage of the explosive growth of information in text form in biomedical papers, selecting appropriate natural language processing (NLP) tools is still difficult for researchers who are not familiar with recent advances in NLP. This article provides a comparative evaluation of several state-of-the-art natural language parsers, focusing on the task of extracting protein–protein interaction (PPI) from biomedical papers. We measure how each parser, and its output representation, contributes to accuracy improvement when the parser is used as a component in a PPI system
クカンブ カクサン キョウチョウ MRI ガゾウ ノ リンショウ オウヨウ ト ユウヨウセイ
Recently the usefulness of diffusion-weighted MR imaging(DWI)in the body regions was reported in several studies. Various malignant tumors may show high signal intensity on DWI reflecting their high cellularity. Quantitative measurement of apparent diffusion coefficient(ADC)may be of value in distinguishing between benign and malignant tumors. We reviewed clinical application of body DWI in various diseases in this article
Difference of signal change by a language task on autistic patients using functional MRI
[Objective] Cerebral function with a language task was evaluated by functional magnetic resonance imaging (fMRI), and the differences of activated pattern and signal changes were compared between autistic patients and normal controls. [Methods] Ten autistic and ten normal subjects were tested by fMRI with a language task requiring the attribution of complex mental states. Activation maps analyzed between two groups were generated and the asymmetry indexes calculated by the quotient of activated pixels of the right frontal lobe divided by those of the left frontal lobe were statistically compared by unpaired t-test. [Results] Both the autistic and the normal subjects showed activation at the bilateral prefrontal cortical areas and the ventral occipito-temporal regions. However, the autistic patients demonstrated more activation at the right frontal lobe than the normal controls. Thus it was considered that in the autistic patients the right-hemisphere was more dominant for the language task than that of the normal controls. The result is consist to the theory that autism is related to early left-hemisphere dysfunction. [Conclusions] We considered that fMRI may be a useful non-invasive method to evaluate the cerebral functional abnormality in autistic patients
Generation of a Mutant Mucor hiemalis Endoglycosidase That Acts on Core-fucosylated N-Glycans
Endo-β-N-acetylglucosaminidase M (Endo-M), an endoglycosidase from the fungus Mucor hiemalis, is a useful tool for chemoenzymatic synthesis of glycoconjugates, including glycoprotein-based therapeutics having a precisely defined glycoform, by virtue of its transglycosylation activity. Although Endo-M has been known to act on various N-glycans, it does not act on core-fucosylated N-glycans, which exist widely in mammalian glycoproteins, thus limiting its application. Therefore, we performed site-directed mutagenesis on Endo-M to isolate mutant enzymes that are able to act on mammalian-type core-α1,6-fucosylated glycans. Among the Endo-M mutant enzymes generated, those in which the tryptophan at position 251 was substituted with alanine or asparagine showed altered substrate specificities. Such mutant enzymes exhibited increased hydrolysis of a synthetic α1,6-fucosylated trimannosyl core structure, whereas their activity on the afucosylated form decreased. In addition, among the Trp-251 mutants, the W251N mutant was most efficient in hydrolyzing the core-fucosylated substrate. W251N mutants could act on the immunoglobulin G-derived core-fucosylated glycopeptides and human lactoferrin glycoproteins. This mutant was also capable of transferring the sialyl glycan from an activated substrate intermediate (sialyl glyco-oxazoline) onto an α1,6-fucosyl-N-acetylglucosaminyl biotin. Furthermore, the W251N mutant gained a glycosynthase-like activity when a N175Q substitution was introduced and it caused accumulation of the transglycosylation products. These findings not only give insights into the substrate recognition mechanism of glycoside hydrolase family 85 enzymes but also widen their scope of application in preparing homogeneous glycoforms of core-fucosylated glycoproteins for the production of potent glycoprotein-based therapeutics
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