86 research outputs found
Determination of the Polarization Observables Cx, Cz, and Py for Final-State Interactions in the Reaction −!d ! K+−!n
The hyperon-nucleon (YN) interaction plays a key role in hypernuclei and strange nuclear matter and is an important part of the baryon-baryon interaction. While considerable progress has been made in the understanding of the nucleon-nucleon (NN) interaction, the YN interaction is less known. Some parameters of the YN potential can be obtained from the NN potential by using SU(3) symmetry. However, due to broken SU(3) there are parameters, which must be obtained from fits to experimental data. High-statistics data on exclusive photoproduction off the deuteron initiated with highly-polarized photons offer a unique opportunity to extract a large sample of polarization observables for final-state interaction events, which can be used to constrain hyperon-nucleon potentials. In this work, we determine the polarization transfers to the , Cx and Cz, from circularly polarized photons, and the hyperon recoil polarization, Py, for final-state interactions (FSI) in the reaction −! d ! K+−! n using data taken with the CLAS detector at the Jefferson laboratory in the E06-103 experiment. Meanwhile, Cx, Cz, and Py for K+ photoproduction off the bound proton were extracted for systematic studies and compared to published CLAS results from K+ photoproduction off a free proton. Our results cover photon energies from 0.9 GeV to 2.6 GeV, a kaon momentum range up to 2 GeV/c, a kaon polar-angle range in laboratory system from 14 to 70, a polar-angle range (relative to the three-momentum transfer to the n system) from 0 to 60, and a n invariant-mass range from 2 GeV/c2 to 2.5 GeV/c2. The FSI results are the first ever obtained for Cx, Cz, and Py and will be used to constrain the theoretical free parameters of the models of the YN potential
Association between mild thyroid dysfunction and clinical outcome in acute coronary syndrome undergoing percutaneous coronary intervention
Background: Thyroid hormones profoundly influence the cardiovascular system, but the effects of mild thyroid dysfunction on the clinical outcome of acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) are not well defined. This study aimed to determine the effect of mild thyroid dysfunction on 12-month prognosis in ACS patients undergoing PCI.
Methods: In this prospective cohort study with a 12-month follow-up, 1560 individuals were divided into four groups based on thyroid hormone levels upon admission: euthyroidism (used as a reference group), subclinical hypothyroidism, subclinical hyperthyroidism, and low triiodothyronine syndrome (low T3 syndrome). The outcomes measured were all-cause mortality, cardiac mortality, nonfatal reinfarction, and unplanned repeat revascularization.
Results: In this study, the prevalence of mild thyroid dysfunction was 10.8%. Multivariate analysis showed that low T3 syndrome, but not subclinical hypothyroidism or subclinical hyperthyroidism, was associated with a higher rate of all-cause (HR 2.553, 95% CI 1.093–5.964, p = 0.030) and cardiac mortality (HR 2.594, 95% CI 1.026–6.559, p = 0.034), compared with the euthyroidism group.
Conclusions: Mild thyroid dysfunction was frequent in patients with ACS undergoing PCI. Low T3 syndrome was the predominant feature and was associated with 12-month adverse outcomes in these patients
GPA-3D: Geometry-aware Prototype Alignment for Unsupervised Domain Adaptive 3D Object Detection from Point Clouds
LiDAR-based 3D detection has made great progress in recent years. However,
the performance of 3D detectors is considerably limited when deployed in unseen
environments, owing to the severe domain gap problem. Existing domain adaptive
3D detection methods do not adequately consider the problem of the
distributional discrepancy in feature space, thereby hindering generalization
of detectors across domains. In this work, we propose a novel unsupervised
domain adaptive \textbf{3D} detection framework, namely \textbf{G}eometry-aware
\textbf{P}rototype \textbf{A}lignment (\textbf{GPA-3D}), which explicitly
leverages the intrinsic geometric relationship from point cloud objects to
reduce the feature discrepancy, thus facilitating cross-domain transferring.
Specifically, GPA-3D assigns a series of tailored and learnable prototypes to
point cloud objects with distinct geometric structures. Each prototype aligns
BEV (bird's-eye-view) features derived from corresponding point cloud objects
on source and target domains, reducing the distributional discrepancy and
achieving better adaptation. The evaluation results obtained on various
benchmarks, including Waymo, nuScenes and KITTI, demonstrate the superiority of
our GPA-3D over the state-of-the-art approaches for different adaptation
scenarios. The MindSpore version code will be publicly available at
\url{https://github.com/Liz66666/GPA3D}.Comment: Accepted by ICCV 202
Learning Effective NeRFs and SDFs Representations with 3D Generative Adversarial Networks for 3D Object Generation: Technical Report for ICCV 2023 OmniObject3D Challenge
In this technical report, we present a solution for 3D object generation of
ICCV 2023 OmniObject3D Challenge. In recent years, 3D object generation has
made great process and achieved promising results, but it remains a challenging
task due to the difficulty of generating complex, textured and high-fidelity
results. To resolve this problem, we study learning effective NeRFs and SDFs
representations with 3D Generative Adversarial Networks (GANs) for 3D object
generation. Specifically, inspired by recent works, we use the efficient
geometry-aware 3D GANs as the backbone incorporating with label embedding and
color mapping, which enables to train the model on different taxonomies
simultaneously. Then, through a decoder, we aggregate the resulting features to
generate Neural Radiance Fields (NeRFs) based representations for rendering
high-fidelity synthetic images. Meanwhile, we optimize Signed Distance
Functions (SDFs) to effectively represent objects with 3D meshes. Besides, we
observe that this model can be effectively trained with only a few images of
each object from a variety of classes, instead of using a great number of
images per object or training one model per class. With this pipeline, we can
optimize an effective model for 3D object generation. This solution is one of
the final top-3-place solutions in the ICCV 2023 OmniObject3D Challenge
Study of the Hyperon-Nucleon Interaction in Exclusive Photoproduction off the Deuteron
The study of final-state interactions in exclusive hyperon photoproduction off the deuteron is a promising approach to extract information about the hyperon-nucleon (YN) interaction. First preliminary results on the azimuthal asymmetry ∑, as well as the polarization transfer coeffcients Ox, Oz, Cx, and Cz for the reaction γd → K+ Λn initiated with linearly and circularly polarized photon beam are presented. The data were taken with the CLAS detector in Hall B of Jefferson Lab during the E06-103 experiment. The large kinematic coverage of the CLAS, combined with the exceptionally high quality of the experimental data, allows identifying and selecting final-state interaction events to extract single- and double-polarization observables and their kinematical dependencies
Mode conversion enables optical pulling force in photonic crystal waveguides
We propose a robust scheme to achieve optical pulling force using the guiding modes supported in a hollow core double-mode photonic crystal waveguide instead of the structured optical beams in free space investigated earlier. The waveguide under consideration supports both the 0th order mode with a larger forward momentum and the 1st order mode with a smaller forward momentum. When the 1st order mode is launched, the scattering by the object inside the waveguide results in the conversion from the 1st order mode to the 0th order mode, thus creating the optical pulling force according to the conservation of linear momentum. We present the quantitative agreement between the results derived from the mode conversion analysis and those from rigorous simulation using the finite-difference in the time-domain numerical method. Importantly, the optical pulling scheme presented here is robust and broadband with naturally occurred lateral equilibriums and has a long manipulation range. Flexibilities of the current configuration make it valuable for the optical force tailoring and optical manipulation operation, especially in microfluidic channel systems
Fatty Acid Oxidation Promotes Cardiomyocyte Proliferation Rate but Does Not Change Cardiomyocyte Number in Infant Mice
Cardiomyocyte proliferation accounts for the increase of cardiac muscle during fetal mammalian heart development. Shortly after birth, cardiomyocyte transits from hyperplasia to hypertrophic growth. Here, we have investigated the role of fatty acid β-oxidation in cardiomyocyte proliferation and hypertrophic growth during early postnatal life in mice. A transient wave of increased cell cycle activity of cardiomyocyte was observed between postnatal day 3 and 5, that proceeded as cardiomyocyte hypertrophic growth and maturation. Assessment of cardiomyocyte metabolism in neonatal mouse heart revealed a myocardial metabolic shift from glycolysis to fatty acid β-oxidation that coincided with the burst of cardiomyocyte cell cycle reactivation and hypertrophic growth. Inhibition of fatty acid β-oxidation metabolism in infant mouse heart delayed cardiomyocyte cell cycle exit, hypertrophic growth and maturation. By contrast, pharmacologic and genetic activation of PPARα, a major regulator of cardiac fatty acid metabolism, induced fatty acid β-oxidation and initially promoted cardiomyocyte proliferation rate in infant mice. As the cell cycle proceeded, activation of PPARα-mediated fatty acid β-oxidation promoted cardiomyocytes hypertrophic growth and maturation, which led to cell cycle exit. As a consequence, activation of PPARα-mediated fatty acid β-oxidation did not alter the total number of cardiomyocytes in infant mice. These findings indicate a unique role of fatty acid β-oxidation in regulating cardiomyocyte proliferation and hypertrophic growth in infant mice
Shengmai San Alleviates Diabetic Cardiomyopathy Through Improvement of Mitochondrial Lipid Metabolic Disorder
Background/Aims: Shengmai San (SMS), prepared from Panax ginseng, Ophiopogon japonicus, and Schisandra chinensisin, has been widely used to treat ischemic disease. In this study, we investigated whether SMS may exert a beneficial effect in diabetic cardiomyopathy through improvement of mitochondrial lipid metabolism. Methods: A leptin receptor-deficient db/db mouse model was utilized, and lean age-matched C57BLKS mice served as non-diabetic controls. Glucose and lipid profiles, myocardial structure, dimension, and function, and heart weight to tibial length ratio were determined. Myocardial ultrastructural morphology was observed with transmission electron microscopy. Protein expression and activity of oxidative phosphorylation (OXPHOS) complex were assessed using western blotting and microplate assay kits. We also observed cellular viability, mitochondrial membrane potential, OXPHOS complex activity, and cellular ATP level in palmitic acid-stimulated H9C2 cardiomyocytes. Changes in the sirtuin (SIRT1)/AMP-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) pathway and mitochondrial uncoupling signaling were assessed using western blotting and quantitative real-time PCR. Results: Leptin receptor-deficient db/db mice exhibit obesity, hyperglycemia, and hyperlipidemia, accompanied by distinct myocardial hypertrophy and diastolic dysfunction. SMS at a dose of 3 g/kg body weight contributed to a recovery of diabetes-induced myocardial hypertrophy and diastolic dysfunction. SMS administration led to an effective restoration of mitochondrial structure and function both in vivo and in vitro. Furthermore, SMS markedly enhanced SIRT1 and p-AMPKα protein levels and decreased the expression of acetylated-PGC-1α and uncoupling protein 2 protein. SMS also restored the depletion of NRF1 and TFAM levels in diabetic hearts and H9C2 cardiomyocytes. Conclusion: The results indicate that SMS may alleviate diabetes-induced myocardial hypertrophy and diastolic dysfunction by improving mitochondrial lipid metabolism
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