2,005 research outputs found
Excited Heavy Quarkonium Production at the LHC through -Boson Decays
Sizable amount of heavy-quarkonium events can be produced through -boson
decays at the LHC. Such channels will provide a suitable platform to study the
heavy-quarkonium properties. The "improved trace technology", which disposes
the amplitude at the amplitude-level, is helpful for deriving
compact analytical results for complex processes. As an important new
application, in addition to the production of the lower-level Fock states
and , we make a further study on the
production of higher-excited -quarkonium Fock states
, and . Here
stands for the -charmonium,
-quarkonium and -bottomonium respectively. We show
that sizable amount of events for those higher-excited states can also be
produced at the LHC. Therefore, we need to take them into consideration for a
sound estimation.Comment: 7 pages, 9 figures and 6 tables. Typo errors are corrected, more
discussions and two new figures have been adde
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Polyethylene microplastics impede the innate immune response by disrupting the extracellular matrix and signaling transduction
Differentiable programming tensor networks for Kitaev magnets
We present a general computational framework to investigate ground state
properties of quantum spin models on infinite two-dimensional lattices using
automatic differentiation-based gradient optimization of infinite projected
entangled-pair states. The approach exploits the variational uniform matrix
product states to contract infinite tensor networks with unit-cell structure
and incorporates automatic differentiation to optimize the local tensors. We
applied this framework to the Kitaev-type model, which involves complex
interactions and competing ground states. To evaluate the accuracy of this
method, we compared the results with exact solutions for the Kitaev model and
found that it has a better agreement for various observables compared to
previous tensor network calculations based on imaginary-time projection.
Additionally, by finding out the ground state with lower variational energy
compared to previous studies, we provided convincing evidence for the existence
of nematic paramagnetic phases and 18-site configuration in the phase diagram
of the - model. Furthermore, in the case of the realistic
--- model for the Kitaev material -RuCl, we
discovered a non-colinear zigzag ground state. Lastly, we also find that the
strength of the critical out-of-plane magnetic field that suppresses such a
zigzag state has a lower transition field value than the previous
finite-cylinder calculations. The framework is versatile and will be useful for
a quick scan of phase diagrams for a broad class of quantum spin models
MUSER: A MUlti-Step Evidence Retrieval Enhancement Framework for Fake News Detection
The ease of spreading false information online enables individuals with
malicious intent to manipulate public opinion and destabilize social stability.
Recently, fake news detection based on evidence retrieval has gained popularity
in an effort to identify fake news reliably and reduce its impact. Evidence
retrieval-based methods can improve the reliability of fake news detection by
computing the textual consistency between the evidence and the claim in the
news. In this paper, we propose a framework for fake news detection based on
MUlti-Step Evidence Retrieval enhancement (MUSER), which simulates the steps of
human beings in the process of reading news, summarizing, consulting materials,
and inferring whether the news is true or fake. Our model can explicitly model
dependencies among multiple pieces of evidence, and perform multi-step
associations for the evidence required for news verification through multi-step
retrieval. In addition, our model is able to automatically collect existing
evidence through paragraph retrieval and key evidence selection, which can save
the tedious process of manual evidence collection. We conducted extensive
experiments on real-world datasets in different languages, and the results
demonstrate that our proposed model outperforms state-of-the-art baseline
methods for detecting fake news by at least 3% in F1-Macro and 4% in F1-Micro.
Furthermore, it provides interpretable evidence for end users.Comment: 12 pages, 5 figures, accepted by KDD '23, ADS trac
Constraining Ultralight Dark Matter through an Accelerated Resonant Search
Experiments aimed at detecting ultralight dark matter typically rely on
resonant effects, which are sensitive to the dark matter mass that matches the
resonance frequency. In this study, we investigate the nucleon couplings of
ultralight axion dark matter using a magnetometer operating in a nuclear
magnetic resonance (NMR) mode. Our approach involves the use of a Ne
spin-based sensor, which features the lowest nuclear magnetic moment among
noble-gas spins. This configuration allows us to achieve an ultrahigh
sensitivity of 0.73 fT/Hz at around 5 Hz, corresponding to energy
resolution of approximately 1.5. Our analysis reveals that under certain
conditions it is beneficial to scan the frequency with steps significantly
larger than the resonance width. The analytical results are in agreement with
experimental data and the scan strategy is potentially applicable to other
resonant searches. Further, our study establishes stringent constraints on
axion-like particles (ALP) in the 4.5--15.5 Hz Compton-frequency range coupling
to neutrons and protons, improving on prior work by several-fold. Within a band
around 4.6--6.6 Hz and around 7.5 Hz, our laboratory findings surpass
astrophysical limits derived from neutron-star cooling. Hence, we demonstrate
an accelerated resonance search for ultralight dark matter, achieving an
approximately 30-fold increase in scanning step while maintaining competitive
sensitivity.Comment: 13 pages, 9 figure
(E)-Ethyl 2-cyano-3-[4-(4,5-diphenyl-1H-imidazol-2-yl)phenyl]acrylate dihydrate
In the title compound, C27H21N3O2·2H2O, the three benzene rings attached to the heterocyclic imidazole ring are not coplanar with the latter, making dihedral angles of 14.8 (2), 31.4 (2), and 37.5 (2)°, respectively, for the benzene ring planes in the 2-, 4- and 5-positions. In the crystal, there are two water molecules which serve as connectors between the acrylate molecules and stabilize the structure via N—H⋯O, O—H⋯N, C—H⋯O and O—H⋯O hydrogen bonding
Chrysin ameliorates synovitis and fibrosis of osteoarthritic fibroblast-like synoviocytes in rats through PERK/TXNIP/NLRP3 signaling
Objective: Synovitis and fibrosis are common pathological features of knee osteoarthritis (KOA). The interaction of synovitis and fibrosis can promote KOA progression. Chrysin (CHR), a natural flavonoid, may treat inflammation and prevent fibrosis. However, the effect and mechanism of CHR in KOA synovitis and fibrosis remains unclear.Methods: The KOA model was established in male SD rats by anterior cruciate ligament transection (ACLT), and histological analysis was used to evaluate synovitis and fibrosis. IL-6, IL-1β and TNF-α mRNA expression in synovial tissue was measured by qRT‒PCR. Immunohistochemistry (IHC) was performed to detect GRP78, ATF-6 and TXNIP expression in vivo. Synovial fibroblasts (SFs) were treated with TGF-β1 to stimulate the inflammatory response and fibrosis. CCK-8 assays were used to detect the viability of CHR-treated SFs. The IL-1β level was detected by immunofluorescence analysis. Coimmunoprecipitation (Co-IP) and double immunofluorescence colocalization were used to detect the physiological interaction between TXNIP and NLRP3. The expression of fibrosis-related mediators and PERK/TXNIP/NLRP3 signaling molecules was detected by western blotting and qRT-PCR.Results: Four weeks after CHR treatment, pathological sections and associated scores showed that CHR improved synovitis and fibrosis in the ACLT model. In vitro, CHR attenuated the TGF-β1-induced inflammatory response and fibrosis in SFs. Moreover, CHR suppressed the expression of synovial fibrosis markers and PERK/TXNIP/NLRP3 signaling molecules in the synovial tissue of rats with ACLT and cultured SFs. More importantly, we found that CHR inhibited TXNIP-NLRP3 interactions in TGF-β-induced SFs.Conclusion: Our findings indicate that CHR can ameliorate synovitis and fibrosis in KOA. The underlying mechanism may be related to the PERK/TXNIP/NLRP3 signaling pathway
Realization of exceptional points along a synthetic orbital angular momentum dimension
Exceptional points (EPs), at which more than one eigenvalue and eigenvector
coalesce, are unique spectral features of Non-Hermiticity (NH) systems. They
exist widely in open systems with complex energy spectra. We experimentally
demonstrate the appearance of paired EPs in a periodical driven degenerate
optical cavity along the synthetic orbital angular momentum (OAM) dimension
with a tunable parameter. The complex-energy band structures and the key
features of EPs, i.e. their Fermi arcs, parity-time symmetry breaking
transition, energy swapping, and half-integer band windings are directly
observed by detecting the cavity's transmission spectrum. Our results advance
the fundamental understanding of NH physics and demonstrate the flexibility of
using the photonic synthetic dimensions to implement NH systems
A chronological review of COVID-19 case fatality rate and its secular trend and investigation of all-cause mortality and hospitalization during the Delta and Omicron waves in the United States: a retrospective cohort study
IntroductionCoronavirus disease 2019 (COVID-19) has caused more than 690 million deaths worldwide. Different results concerning the death rates of the Delta and Omicron variants have been recorded. We aimed to assess the secular trend of case fatality rate (CFR), identify risk factors associated with mortality following COVID-19 diagnosis, and investigate the risks of mortality and hospitalization during Delta and Omicron waves in the United States.MethodsThis study assessed 2,857,925 individuals diagnosed with COVID-19 in the United States from January 2020, to June 2022. The inclusion criterion was the presence of COVID-19 diagnostic codes in electronic medical record or a positive laboratory test of the SARS-CoV-2. Statistical analysis was bifurcated into two components, longitudinal analysis and comparative analysis. To assess the discrepancies in hospitalization and mortality rates for COVID-19, we identified the prevailing periods for the Delta and Omicron variants.ResultsLongitudinal analysis demonstrated four sharp surges in the number of deaths and CFR. The CFR was persistently higher in males and older age. The CFR of Black and White remained higher than Asians since January 2022. In comparative analysis, the adjusted hazard ratios for all-cause mortality and hospitalization were higher in Delta wave compared to the Omicron wave. Risk of all-cause mortality was found to be greater 14–30 days after a COVID-19 diagnosis, while the likelihood of hospitalization was higher in the first 14 days following a COVID-19 diagnosis in Delta wave compared with Omicron wave. Kaplan–Meier analysis revealed the cumulative probability of mortality was approximately 2-fold on day 30 in Delta than in Omicron cases (log-rank p < 0.001). The mortality risk ratio between the Delta and Omicron variants was 1.671 (95% Cl 1.615–1.729, log-rank p < 0.001). Delta also had a significantly increased mortality risk over Omicron in all age groups. The CFR of people aged above 80 years was extremely high as 17.33%.ConclusionMale sex and age seemed to be strong and independent risk factors of mortality in COVID-19. The Delta variant appears to cause more hospitalization and death than the Omicron variant
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