397 research outputs found
Implications on the first observation of charm CPV at LHCb
Very recently, the LHCb Collaboration observed the violation (CPV) in
the charm sector for the first time, with .
This result is consistent with our prediction of obtained in the factorization-assisted
topological-amplitude (FAT) approach in [PRD86,036012(2012)]. It implies that
the current understanding of the penguin dynamics in charm decays in the
Standard Model is reasonable. Motivated by the success of the FAT approach, we
further suggest to measure the decay, which is the next
potential mode to reveal the CPV of the same order as .Comment: 10 page
Branching ratios and direct CP asymmetries in decays
We propose a theoretical framework for analyzing two-body nonleptonic
meson decays, based on the factorization of short-distance (long-distance)
dynamics into Wilson coefficients (hadronic matrix elements of four-fermion
operators). The parametrization of hadronic matrix elements in terms of several
nonperturbative quantities is demonstrated for the decays,
denoting a pseudoscalar meson. We consider the evolution of Wilson coefficients
with energy release in individual decay modes, and the Glauber strong phase
associated with the pion in nonfactorizable annihilation amplitudes, that is
attributed to the unique role of the pion as a Nambu-Goldstone boson and a
quark-anti-quark bound state simultaneously. The above inputs improve the
global fit to the branching ratios involving the meson, and resolves
the long-standing puzzle from the and
branching ratios, respectively. Combining short-distance dynamics associated
with penguin operators and the hadronic parameters determined from the global
fit to branching ratios, we predict direct CP asymmetries, to which the quark
loops and the scalar penguin annihilation give dominant contributions. In
particular, we predict , lower than the LHCb and CDF data.Comment: 17 pages, 3 figures, matches published versio
Branching ratios and direct CP asymmetries in decays
We study the two-body hadronic decays, where () denotes a
pseudoscalar (vector) meson, in the factorization-assisted
topological-amplitude approach proposed in our previous work. This approach is
based on the factorization of short-distance and long-distance dynamics into
Wilson coefficients and hadronic matrix elements of four-fermion operators,
respectively, with the latter being parametrized in terms of several
nonperturbative quantities. We further take into account the -
mixing effect, which improves the global fit to the branching ratios involving
the and mesons. Combining short-distance dynamics associated
with penguin operators and the hadronic parameters determined from the global
fit to branching ratios, we predict direct asymmetries. In particular, the
direct asymmetries in the , , and decays are found to be of , which can be
observed at the LHCb or future Belle II experiment. We also predict the
asymmetry observables of some neutral meson decays.Comment: 16 pages, 2 figure
Delayed response to the photovoltaic performance in a double quantum dot photocell with spatially correlated fluctuation
A viable strategy for enhancing photovoltaic performance in a double quantum
dot (DQD) photocell is to comprehend the underlying quantum physical regime of
charge transfer. This work explores the photovoltaic performance dependent
spatially correlated fluctuation in a DQD photocell. A suggested DQD photocell
model was used to examine the effects of spatially correlated variation on
charge transfer and output photovoltaic efficiency. The charge transfer process
and the process of reaching peak solar efficiency were both significantly
delayed as a result of the spatially correlated fluctuation, and the
anti-spatial correlation fluctuation also resulted in lower output photovoltaic
efficiency. Further results revealed that some structural parameters, such as
gap difference and tunneling coefficient within two dots, could suppress the
delayed response, and a natural adjustment feature was demonstrated on the
delayed response in this DQD photocell model. Subsequent investigation verified
that the delayed response was caused by the spatial correlation fluctuation,
which slowed the generative process of noise-induced coherence, which had
previously been proven to improve quantum photovoltaic performance in quantum
photocells. While anti-spatial correlation fluctuation and a hotter thermal
ambient environment could diminish the condition for noise-induced coherence,
as demonstrated by the reduced photovoltaic capabilities in this suggested DQD
photocell model. As a result, we expect that regulated noise-induced coherence,
via spatially correlated fluctuation, will have a major impact on photovoltaic
qualities in a DQD photocell system. The discovery of its underlying physical
regime of quantum fluctuation will broaden and deepen understanding of quantum
features of electron transfer, as well as provide some indications concerning
quantum techniques for high efficiency DQD solar cells.Comment: 16 pages, 5 figure
(2R,4R)-3-(tert-Butoxycarbonyl)-2-(3-chlorophenyl)-1,3-thiazolidine-4-carboxylic acid monohydrate
In the title compound, C15H18ClNO4S·H2O, the thiazolidine ring displays a half-chair conformation. In the crystal, the water molecules are linked to the organic acid molecules via intermolecular O—H⋯O hydrogen bonds
The 2021 X-ray outburst of magnetar SGR J1935+2154 -- I. Spectral properties
Over a period of multiple active episodes between January 2021 and January
2022, the magnetar SGR J1935+2154 emitted a total of 82 bursts observed by
GECAM-B. Temporal and spectral analyses reveal that the bursts have an average
duration of 145 ms and a fluence ranging from $1.2 \times 10^{-8} \
\mathrm{erg \cdot cm^{-2}}3.7 \times 10^{-5} \ \mathrm{erg \cdot
cm^{-2}}E_{\mathrm{peak}}\alphakT_{\mathrm{min}} \sim 5$ keV of the MBB model, which is
consistent between GECAM-B and GBM-GECAM. This indicates that both samples
originated from similar magnetar bursts. We also reveal the spectra of magnetar
bursts tend to be soft. It indicates that magnetar bursts may be composed of
multiple low BB temperatures and the majority of the BB temperatures are
concentrated around the minimum temperature
Improved colonic inflammation by nervonic acid via inhibition of NF-κB signaling pathway of DSS-induced colitis mice
Background: Nervonic acid (C24:1Δ15, 24:1 ω-9, cis-tetracos-15-enoic acid; NA), a long-chain monounsaturated fatty
acid, plays an essential role in prevention of metabolic diseases, and immune regulation, and has anti-inflammatory
properties. As a chronic, immune-mediated inflammatory disease, ulcerative colitis (UC) can affect the large intestine.
The influences of NA on UC are largely unknown.
Purpose: The present study aimed to decipher the anti-UC effect of NA in the mouse colitis model. Specifically, we
wanted to explore whether NA can regulate the levels of inflammatory factors in RAW264.7 cells and mouse
colitis model.
Methods: To address the above issues, the RAW264.7 cell inflammation model was established by lipopolysaccharide
(LPS), then the inflammatory factors tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Interleukin-1β
(IL-1β), and Interleukin-10 (IL-10) were detected by Enzyme-linked immunosorbent assay (ELISA). The therapeutic
effects of NA for UC were evaluated using C57BL/6 mice gavaged dextran sodium sulfate (DSS). Hematoxylin and
eosin (H&E) staining, Myeloperoxidase (MPO) kit assay, ELISA, immunofluorescence assay, and LC-MS/MS were
used to assess histological changes, MPO levels, inflammatory factors release, expression and distribution of intestinal
tight junction (TJ) protein ZO-1, and metabolic pathways, respectively. The levels of proteins involved in
the nuclear factor kappa-B (NF-κB) pathway in the UC were investigated by western blotting and RT-qPCR.
Results: In vitro experiments verified that NA could reduce inflammatory response and inhibit the activation of
key signal pathways associated with inflammation in LPS-induced RAW264.7 cells. Further, results from the
mouse colitis model suggested that NA could restore intestinal barrier function and suppress NF-κB signal
pathways to ameliorate DSS-induced colitis. In addition, untargeted metabolomics analysis of NA protection
against UC found that NA protected mice from colitis by regulating citrate cycle, amino acid metabolism, pyrimidine
and purine metabolism.
Conclusion: These results suggested that NA could ameliorate the secretion of inflammatory factors, suppress the
NF-κB signaling pathway, and protect the integrity of colon tissue, thereby having a novel role in prevention or
treatment therapy for UC. This work for the first time indicated that NA might be a potential functional food
ingredient for preventing and treating inflammatory bowel disease (IBD).National Key Research and Development, China | Ref. 2021YFE0109200Universidade de Vigo/CISUGThe Provincial Major Scientific and Technological Innovation Project of Shandong | Ref. 2022TZXD0029The Provincial Major Scientific and Technological Innovation Project of Shandong | Ref. 2022TZXD0032The Provincial Major Scientific and Technological Innovation Project of Shandong | Ref. 2021SFGC0904The Provincial Major Scientific and Technological Innovation Project of Shandong | Ref. 2021TZX D004The Natural Science Foundation of Shandong | Ref. ZR2020MH401The Natural Science Foundation of Shandong | Ref. ZR2021QH351National Wheat Industry Technology System of China | Ref. CARS-03–2
Carbon Nanofiber versus Graphene-Based Stretchable Capacitive Touch Sensors for Artificial Electronic Skin.
Stretchable capacitive devices are instrumental for new-generation multifunctional haptic technologies particularly suited for soft robotics and electronic skin applications. A majority of elongating soft electronics still rely on silicone for building devices or sensors by multiple-step replication. In this study, fabrication of a reliable elongating parallel-plate capacitive touch sensor, using nitrile rubber gloves as templates, is demonstrated. Spray coating both sides of a rubber piece cut out of a glove with a conductive polymer suspension carrying dispersed carbon nanofibers (CnFs) or graphene nanoplatelets (GnPs) is sufficient for making electrodes with low sheet resistance values (≈10 Ω sq-1). The electrodes based on CnFs maintain their conductivity up to 100% elongation whereas the GnPs-based ones form cracks before 60% elongation. However, both electrodes are reliable under elongation levels associated with human joints motility (≈20%). Strikingly, structural damages due to repeated elongation/recovery cycles could be healed through annealing. Haptic sensing characteristics of a stretchable capacitive device by wrapping it around the fingertip of a robotic hand (ICub) are demonstrated. Tactile forces as low as 0.03 N and as high as 5 N can be easily sensed by the device under elongation or over curvilinear surfaces
Dense infraspecific sampling reveals cryptic differentiation in the enigmatic hemiparasitic love vine Cassytha filiformis (Lauraceae)
Species delimitation remains a challenge worldwide, especially in highly diverse tropical and subtropical regions. Here, we use an integrative approach that combines morphology, phylogenomics, and species distribution modeling (SDM) to clarify the cryptic differentiation within the enigmatic hemiparasitic love vine Cassytha filiformis (Lauraceae) in China and adjacent regions. We generated complete plastid genomes and nuclear ribosomal sequences for diverse samples from across the species range and compared results with previously published plastid data, recovering two well-supported monophyletic clades. Further, the analysis revealed significant differences in two morphological characters and SDM, indicating distinct environmental factors influencing their distributions. Fossil-calibrated analyses to estimate the origins and diversification patterns for the cryptic species gave divergence age estimates corresponding to the Oligo-Miocene; a period of new ecological opportunities associated with the prevailing East Asian monsoon. Multivariate analyses support the conclusion that southern China and adjacent regions have a different, previously unknown, cryptic lineage of C. filiformis. Our study highlights the importance of using multivariate approach to characterize plant species, as well as the significant role that past climatic changes have played in driving speciation in parasitic plants in tropical and subtropical zones.</p
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