127 research outputs found
Localization, Globalization, and Traveling Chinese Culture
In their article Localization, Globalization, and Traveling Chinese Culture Chengjun Wang and Junhong Ma discuss three main channels of the traveling of Chinese culture to the outside world. Focusing on the situation of bilingualism (i.e., Chinese and English) and the need of spreading Chinese literature and culture especially in the English-speaking world, Wang and Ma argue for localization and globalization. Further, Wang and Ma argue that in order to narrow the gap of the cultural divide between China and the West. In addition to the need for bilingualism especially in the case of translation, they posit that especially the writing of the literary history of Chinese is needed in both English and Chinese (hence their argumentation with regard to bilingualism)
Probing phase transition in neutron stars via the crust-core interfacial mode
Gravitational waves emitted from the binary neutron star (BNS) systems can
carry information about the dense matter phase in these compact stars. The
crust-core interfacial mode is an oscillation mode in a neutron star and it
depends mostly on the equation of the state of the matter in the crust-core
transition region. This mode can be resonantly excited by the tidal field of an
inspiraling-in BNS system, thereby affecting the emitted gravitational waves,
and hence could be used to probe the equation of state in the crust-core
transition region. In this work, we investigate in detail how the first-order
phase transition inside the neutron star affects the properties of the
crust-core interfacial mode, using a Newtonian fluid perturbation theory on a
general relativistic background solution of the stellar structure. Two possible
types of phase transitions are considered: (1) the phase transitions happen in
the fluid core but near the crust-core interface, which results in density
discontinuities; and (2) the strong interaction phase transitions in the dense
core (as in the conventional hybrid star case). These phase transitions'
impacts on interfacial mode properties are discussed. In particular, the former
phase transition has a minor effect on the M-R relation and the adiabatic tidal
deformability, but can significantly affect the interfacial mode frequency and
thereby could be probed using gravitational waves. For the BNS systems, we
discuss the possible observational signatures of these phase transitions in the
gravitational waveforms and their detectability. Our work enriches the
exploration of the physical properties of the crust-core interfacial mode and
provides a promising method for probing the phase transition using the
seismology of a compact star.Comment: 18 pages, 14 figure
Evolutionary history of two evergreen Rhododendron species as revealed by chromosome-level genome assembly
BackgroundThe genus Rhododendron (Ericaceae), a species-rich and widely distributed genus of woody plants, is distinguished for the beautiful and diverse flowers. Rhododendron delavayi Franch. and Rhododendron irroratum Franch., are highly attractive species widely distributed in south-west China and abundant new varieties have been selected from their genetic resources.MethodsWe constructed chromosome-scale genome assemblies for Rhododendron delavayi and Rhododendron irroratum. Phylogenetic and whole-genome duplication analyses were performed to elucidate the evolutionary history of Rhododendron. Further, different types of gene duplications were identified and their contributions to gene family expansion were investigated. Finally, comprehensive characterization and evolutionary analysis of R2R3-MYB and NBS-encoding genes were conducted to explore their evolutionary patterns.ResultsThe phylogenetic analysis classified Rhododendron species into two sister clades, ‘rhododendrons’ and ‘azaleas’. Whole-genome duplication (WGD) analysis unveiled only one WGD event that occurred in Rhododendron after the ancestral γ triplication. Gene duplication and gene family expansion analyses suggested that the younger tandem and proximal duplications contributed greatly to the expansion of gene families involved in secondary metabolite biosynthesis and stress response. The candidate R2R3-MYB genes likely regulating anthocyanin biosynthesis and stress tolerance in Rhododendron will facilitate the breeding for ornamental use. NBS-encoding genes had undergone significant expansion and experienced species-specific gain and loss events in Rhododendron plants.ConclusionsThe reference genomes presented here will provide important genetic resources for molecular breeding and genetic improvement of plants in this economically important Rhododendron genus
Rosmarinic Acid Alleviates the Endothelial Dysfunction Induced by Hydrogen Peroxide in Rat Aortic Rings via Activation of AMPK
Endothelial dysfunction is the key player in the development and progression of vascular events. Oxidative stress is involved in endothelial injury. Rosmarinic acid (RA) is a natural polyphenol with antioxidative, antiapoptotic, and anti-inflammatory properties. The present study investigates the protective effect of RA on endothelial dysfunction induced by hydrogen peroxide (H2O2). Compared with endothelium-denuded aortic rings, the endothelium significantly alleviated the decrease of vasoconstrictive reactivity to PE and KCl induced by H2O2. H2O2 pretreatment significantly injured the vasodilative reactivity to ACh in endothelium-intact aortic rings in a concentration-dependent manner. RA individual pretreatment had no obvious effect on the vasoconstrictive reaction to PE and KCl, while its cotreatment obviously mitigated the endothelium-dependent relaxation impairments and the oxidative stress induced by H2O2. The RA cotreatment reversed the downregulation of AMPK and eNOS phosphorylation induced by H2O2 in HAEC cells. The pretreatment with the inhibitors of AMPK (compound C) and eNOS (L-NAME) wiped off RA’s beneficial effects. All these results demonstrated that RA attenuated the endothelial dysfunction induced by oxidative stress by activating the AMPK/eNOS pathway
Impact of CRAMP-34 on Pseudomonas aeruginosa biofilms and extracellular metabolites
Biofilm is a structured community of bacteria encased within a self-produced extracellular matrix. When bacteria form biofilms, they undergo a phenotypic shift that enhances their resistance to antimicrobial agents. Consequently, inducing the transition of biofilm bacteria to the planktonic state may offer a viable approach for addressing infections associated with biofilms. Our previous study has shown that the mouse antimicrobial peptide CRAMP-34 can disperse Pseudomonas aeruginosa (P. aeruginosa) biofilm, and the potential mechanism of CRAMP-34 eradicate P. aeruginosa biofilms was also investigated by combined omics. However, changes in bacterial extracellular metabolism have not been identified. To further explore the mechanism by which CRAMP-34 disperses biofilm, this study analyzed its effects on the extracellular metabolites of biofilm cells via metabolomics. The results demonstrated that a total of 258 significantly different metabolites were detected in the untargeted metabolomics, of which 73 were downregulated and 185 were upregulated. Pathway enrichment analysis of differential metabolites revealed that metabolic pathways are mainly related to the biosynthesis and metabolism of amino acids, and it also suggested that CRAMP-34 may alter the sensitivity of biofilm bacteria to antibiotics. Subsequently, it was confirmed that the combination of CRAMP-34 with vancomycin and colistin had a synergistic effect on dispersed cells. These results, along with our previous findings, suggest that CRAMP-34 may promote the transition of PAO1 bacteria from the biofilm state to the planktonic state by upregulating the extracellular glutamate and succinate metabolism and eventually leading to the dispersal of biofilm. In addition, increased extracellular metabolites of myoinositol, palmitic acid and oleic acid may enhance the susceptibility of the dispersed bacteria to the antibiotics colistin and vancomycin. CRAMP-34 also delayed the development of bacterial resistance to colistin and ciprofloxacin. These results suggest the promising development of CRAMP-34 in combination with antibiotics as a potential candidate to provide a novel therapeutic approach for the prevention and treatment of biofilm-associated infections
Prior knowledge auxiliary for few-shot pest detection in the wild
One of the main techniques in smart plant protection is pest detection using deep learning technology, which is convenient, cost-effective, and responsive. However, existing deep-learning-based methods can detect only over a dozen common types of bulk agricultural pests in structured environments. Also, such methods generally require large-scale well-labeled pest data sets for their base-class training and novel-class fine-tuning, and these significantly hinder the further promotion of deep convolutional neural network approaches in pest detection for economic crops, forestry, and emergent invasive pests. In this paper, a few-shot pest detection network is introduced to detect rarely collected pest species in natural scenarios. Firstly, a prior-knowledge auxiliary architecture for few-shot pest detection in the wild is presented. Secondly, a hierarchical few-shot pest detection data set has been built in the wild in China over the past few years. Thirdly, a pest ontology relation module is proposed to combine insect taxonomy and inter-image similarity information. Several experiments are presented according to a standard few-shot detection protocol, and the presented model achieves comparable performance to several representative few-shot detection algorithms in terms of both mean average precision (mAP) and mean average recall (mAR). The results show the promising effectiveness of the proposed few-shot detection architecture
Phosphomolybdic acid-responsive Pickering emulsions stabilized by ionic liquid functionalized Janus nanosheets
<p><b>A</b> Representative photomicrographs of Caspase-3 immunofluorescence staining (400×). <b>B</b> Quantification of Caspase-3 fluorescence intensity in different groups. <b>C</b> Representative Western blot band of Caspase-3 activation in the ischemic cortex at 24 h after reperfusion. <b>D</b> Effect of LBP (40 mg/kg) on the Caspase-3 activation in MCAO mice cortex at 24 h after reperfusion. Data are expressed as mean±SEM (n = 6). <sup>##</sup>P<0.01 vs. sham-operated group; **P<0.01 vs. vehicle group.</p
Intestinal Absorption and First-Pass Metabolism of Polyphenol Compounds in Rat and Their Transport Dynamics in Caco-2 Cells
<div><h3>Background</h3><p>Polyphenols, a group of complex naturally occurring compounds, are widely distributed throughout the plant kingdom and are therefore readily consumed by humans. The relationship between their chemical structure and intestinal absorption, transport, and first-pass metabolism remains unresolved, however.</p> <h3>Methods</h3><p>Here, we investigated the intestinal absorption and first-pass metabolism of four polyphenol compounds, apigenin, resveratrol, emodin and chrysophanol, using the <em>in vitro</em> Caco-2 cell monolayer model system and <em>in situ</em> intestinal perfusion and <em>in vivo</em> pharmacokinetic studies in rats, so as to better understand the relationship between the chemical structure and biological fate of the dietary polyphenols.</p> <h3>Conclusion</h3><p>After oral administration, emodin and chrysophanol exhibited different absorptive and metabolic behaviours compared to apigenin and resveratrol. The differences in their chemical structures presumably resulted in differing affinities for drug-metabolizing enzymes, such as glucuronidase and sulphatase, and transporters, such as MRP2, SGLT1, and P-glycoprotein, which are found in intestinal epithelial cells.</p> </div
Decadal soil carbon accumulation across Tibetan permafrost regions
Acknowledgements We thank the members of Peking University Sampling Teams (2001–2004) and IBCAS Sampling Teams (2013–2014) for assistance in field data collection. We also thank the Forestry Bureau of Qinghai Province and the Forestry Bureau of Tibet Autonomous Region for their permission and assistance during the sampling process. This study was financially supported by the National Natural Science Foundation of China (31670482 and 31322011), National Basic Research Program of China on Global Change (2014CB954001 and 2015CB954201), Chinese Academy of Sciences-Peking University Pioneer Cooperation Team, and the Thousand Young Talents Program.Peer reviewedPostprintPostprin
Comparative analyses of leaf anatomy of dicotyledonous species in Tibetan and Inner Mongolian grasslands
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