1,830 research outputs found

    Galactic Disk Bulk Motions as Revealed by the LSS-GAC DR2

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    We report a detailed investigation of the bulk motions of the nearby Galactic stellar disk, based on three samples selected from the LSS-GAC DR2: a global sample containing 0.57 million FGK dwarfs out to \sim 2 kpc, a local subset of the global sample consisting \sim 5,400 stars within 150 pc, and an anti-center sample containing \sim 4,400 AFGK dwarfs and red clump stars within windows of a few degree wide centered on the Galactic anti-center. The global sample is used to construct a three-dimensional map of bulk motions of the Galactic disk from the solar vicinity out to \sim 2 kpc with a spatial resolution of \sim 250 pc. Typical values of the radial and vertical components of bulk motion range from -15 km s1^{-1} to 15 km s1^{-1}, while the lag behind the circular speed dominates the azimuthal component by up to \sim 15 km s1^{-1}. The map reveals spatially coherent, kpc-scale stellar flows in the disk, with typical velocities of a few tens km s1^{-1}. Bending- and breathing-mode perturbations are clearly visible, and vary smoothly across the disk plane. Our data also reveal higher-order perturbations, such as breaks and ripples, in the profiles of vertical motion versus height. From the local sample, we find that stars of different populations exhibit very different patterns of bulk motion. Finally, the anti-center sample reveals a number of peaks in stellar number density in the line-of-sight velocity versus distance distribution, with the nearer ones apparently related to the known moving groups. The "velocity bifurcation" reported by Liu et al. (2012) at Galactocentric radii 10--11 kpc is confirmed. However, just beyond this distance, our data also reveal a new triple-peaked structure.Comment: 27 pages, 17 figures, Accepted for publication in a special issue of Research in Astronomy and Astrophysics on LAMOST science

    Seeing Beyond the Brain: Conditional Diffusion Model with Sparse Masked Modeling for Vision Decoding

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    Decoding visual stimuli from brain recordings aims to deepen our understanding of the human visual system and build a solid foundation for bridging human and computer vision through the Brain-Computer Interface. However, reconstructing high-quality images with correct semantics from brain recordings is a challenging problem due to the complex underlying representations of brain signals and the scarcity of data annotations. In this work, we present MinD-Vis: Sparse Masked Brain Modeling with Double-Conditioned Latent Diffusion Model for Human Vision Decoding. Firstly, we learn an effective self-supervised representation of fMRI data using mask modeling in a large latent space inspired by the sparse coding of information in the primary visual cortex. Then by augmenting a latent diffusion model with double-conditioning, we show that MinD-Vis can reconstruct highly plausible images with semantically matching details from brain recordings using very few paired annotations. We benchmarked our model qualitatively and quantitatively; the experimental results indicate that our method outperformed state-of-the-art in both semantic mapping (100-way semantic classification) and generation quality (FID) by 66% and 41% respectively. An exhaustive ablation study was also conducted to analyze our framework.Comment: 8 pages, 9 figures, 2 tables, accepted by CVPR2023, see https://mind-vis.github.io/ for more informatio

    Heat Shock Protein 70 Protects the Heart from Ischemia/Reperfusion Injury through Inhibition of p38 MAPK Signaling.

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    BackgroundHeat shock protein 70 (Hsp70) has been shown to exert cardioprotection. Intracellular calcium ([Ca2+]i) overload induced by p38 mitogen-activated protein kinase (p38 MAPK) activation contributes to cardiac ischemia/reperfusion (I/R) injury. However, whether Hsp70 interacts with p38 MAPK signaling is unclear. Therefore, this study investigated the regulation of p38 MAPK by Hsp70 in I/R-induced cardiac injury.MethodsNeonatal rat cardiomyocytes were subjected to oxygen-glucose deprivation for 6 h followed by 2 h reoxygenation (OGD/R), and rats underwent left anterior artery ligation for 30 min followed by 30 min of reperfusion. The p38 MAPK inhibitor (SB203580), Hsp70 inhibitor (Quercetin), and Hsp70 short hairpin RNA (shRNA) were used prior to OGD/R or I/R. Cell viability, lactate dehydrogenase (LDH) release, serum cardiac troponin I (cTnI), [Ca2+]i levels, cell apoptosis, myocardial infarct size, mRNA level of IL-1β and IL-6, and protein expression of Hsp70, phosphorylated p38 MAPK (p-p38 MAPK), sarcoplasmic/endoplasmic reticulum Ca2+-ATPase2 (SERCA2), phosphorylated signal transducer and activator of transcription3 (p-STAT3), and cleaved caspase3 were assessed.ResultsPretreatment with a p38 MAPK inhibitor, SB203580, significantly attenuated OGD/R-induced cell injury or I/R-induced myocardial injury, as evidenced by improved cell viability and lower LDH release, resulted in lower serum cTnI and myocardial infarct size, alleviation of [Ca2+]i overload and cell apoptosis, inhibition of IL-1β and IL-6, and modulation of protein expressions of p-p38 MAPK, SERCA2, p-STAT3, and cleaved-caspase3. Knockdown of Hsp70 by shRNA exacerbated OGD/R-induced cell injury, which was effectively abolished by SB203580. Moreover, inhibition of Hsp70 by quercetin enhanced I/R-induced myocardial injury, while SB203580 pretreatment reversed the harmful effects caused by quercetin.ConclusionsInhibition of Hsp70 aggravates [Ca2+]i overload, inflammation, and apoptosis through regulating p38 MAPK signaling during cardiac I/R injury, which may help provide novel insight into cardioprotective strategies

    Tetherin inhibits prototypic foamy virus release

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    Background: Tetherin (also known as BST-2, CD317, and HM1.24) is an interferon- induced protein that blocks the release of a variety of enveloped viruses, such as retroviruses, filoviruses and herpesviruses. However, the relationship between tetherin and foamy viruses has not been clearly demonstrated. Results: In this study, we found that tetherin of human, simian, bovine or canine origin inhibits the production of infectious prototypic foamy virus (PFV). The inhibition of PFV by human tetherin is counteracted by human immunodeficiency virus type 1 (HIV-1) Vpu. Furthermore, we generated human tetherin transmembrane domain deletion mutant (delTM), glycosyl phosphatidylinositol (GPI) anchor deletion mutant (delGPI), and dimerization and glycosylation deficient mutants. Compared with wild type tetherin, the delTM and delGPI mutants only moderately inhibited PFV production. In contrast, the dimerization and glycosylation deficient mutants inhibit PFV production as efficiently as the wild type tetherin. Conclusions: These results demonstrate that tetherin inhibits the release and infectivity of PFV, and this inhibition is antagonized by HIV-1 Vpu. Both the transmembrane domain and the GPI anchor of tetherin are important for the inhibition of PFV, whereas the dimerization and the glycosylation of tetherin are dispensable

    The use of Rheum palmatum L. In the treatment of acute respiratory distress syndrome: a meta-analysis of randomized, controlled trials

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    Background: Chinese medicine theory shows that “lung being connected with large intestine”, and the modern western medicine also shows that the lung and intestinal tract affect each other in physiological and pathological conditions. If the lung ventilation dysfunction is caused by inflammatory exudate or secretions obstruction of the small airway ventilation, blood gas partial pressure is increased and intestinal gas absorption difficulty may lead to intestinal inflation and dysfunction (Wang N et al., 2011). Rheum palmatum L. can play the roles of anti-coagulation and anti-thrombosis, and improve microcirculation through lowering the endotoxin-induced permeability of microvascular tissue, reducing tissue oedema, decreasing inflammatory exudation and necrosis, and enhancing cyto-protection mechanism (Yang TZ et al., 2014). Therefore, systemic evaluation of the evidence pertaining to the usage of Rheum palmatum L. in treating acute lung injury and acute respiratory distress syndrome (ARDS) has significant clinical significance.Materials and Methods: Various Electronic Databases CBM, CNKI, VIP, Wanfang, PubMed and Cochrane Library were searched until December 2015. Numerous randomized-controlled trials (RCTs) evaluating the efficacy of Rheum palmatum L. for the treatment of acute lung injury and acute respiratory distress syndrome were collected. The quality of the included studies was evaluated and a meta-analysis was performed using the RevMan5.0 software.Results: Eight RCTs involving 489 patients were selected for this review. The results of the Meta-analysis revealed that Rheum palmatum L. therapy, combined with routine comprehensive treatment, was significantly superior to that of routine comprehensive treatment alone, in the areas of decreasing mortality, the mechanical ventilation time, the level of interleukin-6,8 and the untoward effect, and also in improving arterial blood gas (PaO2/FiO2, PaO2) (P<0.05).Conclusion: Compared with treatment with routine comprehensive alone, Rheum palmatum L. treatment combined with routine comprehensive, has been shown to effectively decrease the mortality, mechanical ventilation time and ameliorate the arterial blood gas, the cytokine levels, and the untoward effect. However, the evidence appears not to be very compelling due to the poor quality of the original studies.Keywords: Rheum palmatum L., Western medicine therapy, ALI/ARDS, Systematic Review, Meta-analysi

    Recombination frequencies between cultivated soybean (Glycine max) and its wild relative Glycine soja based on molecular marker analysis

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    Close relatives of cultivated crops provide an invaluable source of genetic variation in crop improvement and exploiting such variation often forms a critical part in a breeding program. The usability of the wild soybean Glycine soja was investigated in this study by analyzing populations derived from two wide crosses between a common cultivar and two different G. soja accessions using simple sequence repeat (SSR) markers. Consistent reductions in recombination frequencies were not detected in either of these two wide crosses and the results does not seem to be confined to the particular populations or the wild genotypes used. In variance with previous reports that domestication-related traits are often controlled by one or two major loci, these recombination results strongly indicate that linkage drag should not be a major concern in transferring genes from the wild taxon into the cultigen, although backcross would still be required to minimize undesirable chromatins.Keywords: Glycine max, Glycine soja, linkage drags, recombination frequency, molecular markersAfrican Journal of Biotechnology Vol. 12(22), pp. 3522-352

    Berberine Ameliorates High Glucose-Induced Cardiomyocyte Injury via AMPK Signaling Activation to Stimulate Mitochondrial Biogenesis and Restore Autophagic Flux

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    Background: Type II diabetes (T2D)-induced cardiomyocyte hypertrophy is closely linked to the impairment of mitochondrial function. Berberine has been shown to be a promising effect for hypoglycemia in T2D models. High glucose-induced cardiomyocyte hypertrophy in vitro has been reported. The present study investigated the protective effect and the underlying mechanism of berberine on high glucose-induced H9C2 cell line.Methods: High glucose-induced H9C2 cell line was used to mimic the hyperglycemia resulting in cardiomyocyte hypertrophy. Berberine was used to rescue in this model and explore the mechanism in it. Confocal microscopy, immunofluorescence, RT-PCR, and western blot analysis were performed to evaluate the protective effects of berberine in high glucose-induced H9C2 cell line.Results: Berberine dramatically alleviated hypertrophy of H9C2 cell line and significantly ameliorated mitochondrial function by rectifying the imbalance of fusion and fission in mitochondrial dynamics. Furthermore, berberine further promoted mitogenesis and cleared the damaged mitochondria via mitophagy. In addition, berberine also restored autophagic flux in high glucose-induced cardiomyocyte injury via AMPK signaling pathway activation.Conclusion: Berberine ameliorates high glucose-induced cardiomyocyte injury via AMPK signaling pathway activation to stimulate mitochondrial biogenesis and restore autophagicflux in H9C2 cell line
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