1,028 results on '"Xiao, Ming-Li"'
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2. Hypothalamic-hindbrain circuit for consumption-induced fear regulation
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Qin Wang, Rui-Yue Sun, Jia-Xue Hu, Yan-Hui Sun, Chun-Yue Li, Huiqian Huang, Hao Wang, and Xiao-Ming Li
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Science - Abstract
Abstract To ensure survival, animals must sometimes suppress fear responses triggered by potential threats during feeding. However, the mechanisms underlying this process remain poorly understood. In the current study, we demonstrated that when fear-conditioned stimuli (CS) were presented during food consumption, a neural projection from lateral hypothalamic (LH) GAD2 neurons to nucleus incertus (NI) relaxin-3 (RLN3)-expressing neurons was activated, leading to a reduction in CS-induced freezing behavior in male mice. LHGAD2 neurons established excitatory connections with the NI. The activity of this neural circuit, including NIRLN3 neurons, attenuated CS-induced freezing responses during food consumption. Additionally, the lateral mammillary nucleus (LM), which received NIRLN3 projections, along with RLN3 signaling in the LM, mediated the decrease in freezing behavior. Collectively, this study identified an LHGAD2-NIRLN3-LM circuit involved in modulating fear responses during feeding, thereby enhancing our understanding of how animals coordinate nutrient intake with threat avoidance.
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- 2024
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3. Cloud inversion analysis of surrounding rock parameters for underground powerhouse based on PSO-BP optimized neural network and web technology
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Qu, Long, Xie, Hong-Qiang, Pei, Jian-Liang, Li, You-Gen, Wu, Jia-Ming, Feng, Gan, and Xiao, Ming-Li
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- 2024
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4. Analytical and experimental analysis of concrete temperature and energy considering open-air environmental variations
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Yang, Wen-Jian, Li, Peng, Zhuo, Li, Pang, Ming-Liang, Xie, Hong-Qiang, and Xiao, Ming-Li
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- 2024
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5. Mechanical Responses of a Porous Red Sandstone to Quasi-Static Cyclic Loads Under Uniaxial Compression
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Zheng, Zhao-Qiang, Liu, Huai-Zhong, Xie, Hong-Qiang, He, Jiang-Da, Xiao, Ming-Li, and Zhuo, Li
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- 2024
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6. Inhibition of the P38 MAPK/NLRP3 pathway mitigates cognitive dysfunction and mood alterations in aged mice after abdominal surgery plus sevoflurane
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Jin-Meng Lv, Yi-Long Gao, Lu-Ying Wang, Bao-Dong Li, Yong-Lin Shan, Zi-Qiang Wu, Qing-Meng Lu, Heng-Yue Peng, Ting-Ting Zhou, Xiao-Ming Li, and Li-Min Zhang
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Cognitive dysfunction ,Perioperative stress ,Aging ,P38 MAPK ,NLRP3 ,GSK3β ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Background: Cognitive dysfunction, encompassing perioperative psychological distress and cognitive impairment, is a prevalent postoperative complication within the elderly population, and in severe cases, it may lead to dementia. Building upon our prior research that unveiled a connection between postoperative mood fluctuations and cognitive dysfunction with the phosphorylation of P38, this present investigation aims to delve deeper into the involvement of the P38 MAPK/NLRP3 pathway in perioperative neurocognitive disorders (PND) in an abdominal exploratory laparotomy (AEL) aged mice model. Methods: C57BL/6 mice (male, 18-month-old) underwent AEL with 3 % anesthesia. Then, inhibitors targeting P38 MAPK (SB202190, 1 mg/kg) and GSK3β (TWS119, 10 mg/kg) were administered multiple times daily for 7 days post-surgery. The NLRP3-cKO AEL and WT AEL groups only underwent the AEL procedure. Behavioral assessments, including the open field test (OFT), novel object recognition (NOR), force swimming test (FST), and fear conditioning (FC), were initiated on postoperative day 14. Additionally, mice designated for neuroelectrophysiological monitoring had electrodes implanted on day 14 before surgery and underwent novel object recognition while their local field potential (LFP) was concurrently recorded on postoperative day 14. Lastly, after they were euthanasized, pathological analysis and western blot were performed. Results: SB202190, TWS119, and astrocyte-conditional knockout NLRP3 all ameliorated the cognitive impairment behaviors induced by AEL in mice and increased mean theta power during novel location exploration. However, it is worth noting that SB202190 may exacerbate postoperative depressive and anxiety-like behaviors in mice, while TWS119 may induce impulsive behaviors. Conclusions: Our study suggests that anesthesia and surgical procedures induce alterations in mood and cognition, which may be intricately linked to the P38 MAPK/NLRP3 pathway.
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- 2024
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7. Dynamic encoding of temperature in the central circadian circuit coordinates physiological activities
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Hailiang Li, Zhiyi Li, Xin Yuan, Yue Tian, Wenjing Ye, Pengyu Zeng, Xiao-Ming Li, and Fang Guo
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Science - Abstract
Abstract The circadian clock regulates animal physiological activities. How temperature reorganizes circadian-dependent physiological activities remains elusive. Here, using in-vivo two-photon imaging with the temperature control device, we investigated the response of the Drosophila central circadian circuit to temperature variation and identified that DN1as serves as the most sensitive temperature-sensing neurons. The circadian clock gate DN1a’s diurnal temperature response. Trans-synaptic tracing, connectome analysis, and functional imaging data reveal that DN1as bidirectionally targets two circadian neuronal subsets: activity-related E cells and sleep-promoting DN3s. Specifically, behavioral data demonstrate that the DN1a-E cell circuit modulates the evening locomotion peak in response to cold temperature, while the DN1a-DN3 circuit controls the warm temperature-induced nocturnal sleep reduction. Our findings systematically and comprehensively illustrate how the central circadian circuit dynamically integrates temperature and light signals to effectively coordinate wakefulness and sleep at different times of the day, shedding light on the conserved neural mechanisms underlying temperature-regulated circadian physiology in animals.
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- 2024
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8. Multifunctional ultraflexible neural probe for wireless optogenetics and electrophysiology
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Suhao Wang, Lixuan Li, Shun Zhang, Qianqian Jiang, Pengxian Li, Chengjun Wang, Rui Xiao, Xiao-Ming Li, and Jizhou Song
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Multifunctional neural probe ,Flexible neural probe ,Electrophysiology ,Optogenetics ,Science (General) ,Q1-390 - Abstract
Electrophysiology and optogenetics are pivotal in neuroscience for probing and modulating neural activities, playing a vital role in unraveling the complexities of brain functionality. Despite their importance, the efficacy of existing devices is hampered by insufficient functional integration, pronounced foreign body reactions, and physical constraints that impede natural animal behaviors. Here, we develop a multifunctional, ultraflexible neural probe designed for simultaneous electrophysiological monitoring and optical neural modulation, along with mechanical properties that are conducive to flexibility and compliance. By integrating a wireless neural signal acquisition and stimulation circuit, we achieved wireless recording of brain signals in mice and wireless optogenetic control over their locomotor behavior. The multifunctional ultraflexible probe presented in this study holds substantial promise for closed-loop brain-machine interfaces and deepening our understanding of neural circuit functions. This innovative approach addresses the aforementioned limitations by a comprehensive solution for in vivo neural interrogation and manipulation, marking a significant advancement in the tools available for neuroscience research.
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- 2024
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9. Complex function method considering rock strength for determining critical warning deformation of deep-buried complex cavern
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Luo, Ao-Ying, Zhuo, Li, Liu, Huai-Zhong, Xie, Hong-Qiang, Xu, Nu-Wen, Xiao, Ming-Li, and Shuai, Yong-Jian
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- 2024
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10. Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793
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Zhen Ying, Xiao-Ming Li, Sui-Qun Yang, Hong-Lei Li, Xin Li, Bin-Gui Wang, and Ling-Hong Meng
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antimicrobial activity ,cold seep ,pseudallescheria boydii ,sesquiterpenoid ,Science ,Organic chemistry ,QD241-441 - Abstract
Pseudallenes A and B (1 and 2), the new and rare examples of sulfur-containing ovalicin derivatives, along with three known analogues 3–5, were isolated and identified from the culture extract of Pseudallescheria boydii CS-793, a fungus obtained from the deep-sea cold seep sediments. Their structures were established by detailed interpretation of NMR spectroscopic and mass spectrometric data. X-ray crystallographic analysis confirmed and established the structures and absolute configurations of compounds 1–3, thus providing the first characterized crystal structure of an ovalicin-type sesquiterpenoid. In the antimicrobial assays, compounds 1–3 showed broad-spectrum inhibitory activities against several plant pathogens with MIC values ranging from 2 to 16 μg/mL.
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- 2024
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11. Absolute radiometric calibration evaluation of the thermal infrared spectrometer onboard SDGSAT-1
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Yonghong Hu, Xiao-Ming Li, Changyong Dou, Gensuo Jia, Zhuoyue Hu, Anlun Xu, Yongzheng Ren, Lin Yan, Ning Wang, Zhenzhen Cui, and Fansheng Chen
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sdgsat-1 ,thermal infrared spectrometer ,radiometric calibration ,lake erhai ,brightness temperature ,Mathematical geography. Cartography ,GA1-1776 - Abstract
A thermal infrared spectrometer is an important sensor onboard the SDGSAT-1 dedicated to serving the 2030 Agenda for Sustainable Development of the United Nations. Field campaigns were conducted from January to December 2022 to evaluate its radiometric calibrations. A radiance-based calibration method was used to derive the spectral radiance of the lake surface around the satellite overpass using a boat-deployed TIR spectrometer or radiometer. The radiometric calibration conditions were quantified by examining the temperature bias between the satellite-based brightness temperature and the predicted at-sensor brightness temperature. Our results indicated that the average brightness temperature bias reached 0.772 K, −1.032 K, and −0.300 K, with RMSEs of 1.00, 1.10, and 0.43 K in bands 1, 2 and 3, respectively. Eighty percent of the field experiments achieved a high calibration accuracy with temperature biases of less than 1 K, and the calibration accuracy of band 3 was better than that of other bands. Atmospheric conditions and surface characterization play important roles in determining the calibration accuracy through surface observations and atmospheric transfer simulations. With the increasing need for SDGSAT-1 products, periodic field experiments are needed to monitor and improve the operational radiometric calibration of satellite instruments to create high-resolution and reasonable scientific datasets.
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- 2023
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12. Dilatancy and Multi-Scale failure characteristics of a foliated rock under triaxial confinement unloading conditions
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Zheng, Zhao-Qiang, Kong, Qing-Xin, Xiao, Ming-Li, Pei, Jian-Liang, Zhuo, Li, and He, Jiang-Da
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- 2024
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13. Enhancing SDGSAT-1 night light images using a panchromatic guidance denoising algorithm
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Ning Wang, Yonghong Hu, Xiao-Ming Li, Yiling Lan, Chuanli Kang, Lin Yan, Changyong Dou, and Chen Miao
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SDGSAT-1 ,Strip Noise ,Nighttime Light Images ,Denoising Algorithm ,Physical geography ,GB3-5030 ,Environmental sciences ,GE1-350 - Abstract
The Glimmer Imager on board the Sustainable Development Science Satellite 1 (SDGSAT-1) is capable of providing high-resolution nighttime light images. However, the presence of stripe noise and dark current noise in L4A images affects the authenticity of image information, thus limiting its scientific applications. This study proposes a panchromatic guidance denoising algorithm to enhance the quality of nighttime light images based on the spectral consistency properties between the panchromatic and RGB channels. This algorithm utilizes two low-noise panchromatic bands to obtain a denoised light area and subsequently removes a significant amount of noise from non-light areas in the RGB bands based on this light area. Our results indicate that this algorithm can effectively remove noise from SDGSAT-1 nighttime light images, achieving a noise removal rate greater than 99.8% in the selected dark ocean area. It also preserves more reasonable radiometric characteristics and spatial details of high-spatial resolution nighttime light images when compared to other popular denoising algorithms. The perturbation caused by moonlight can be effectively eliminated using this algorithm, which further improves the comparability and application of SDGSAT-1 nighttime light images under different lunar phases.
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- 2024
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14. Regulation of Dihydroartemisinin on the pathological progression of laryngeal carcinoma through the periostin/YAP/IL-6 pathway
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Xin-yu Zhang, Rui-cong Li, Cong Xu, and Xiao-ming Li
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Dihydroartemisinin ,Laryngeal carcinoma ,Periostin ,YAP ,IL-6 ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Objective: Laryngeal cancer (LC) is one of the most common squamous cell carcinomas of the head and neck in clinical practice, and its incidence has been increasing in recent years, but the prognosis of the patients is not favorable. Hence, it is critical to re-understand and deeply study the causes and mechanisms of LC and explore new effective treatment methods and strategies. In this study, we analyzed the effect of Dihydroartemisinin (DHA) on the pathological progression of LC through the periostin (POSTN)/Yes-associated protein (YAP)/interleukin (IL)-6 pathway, which can provide new clinical references and guidelines. Methods: POSTN, YAP, and IL-6 levels in 18 pairs of fresh LC tissues and adjacent counterparts in our hospital were detected. Additionally, LC TU686 cell line was purchased for DHA treatment of various concentrations to detect changes in cell biological behavior. Finally, we built a tumor-bearing mouse model with C57BL/6 mice and intragastrically administrated DHA to the animals to observe the growth of living tumors and to measure POSTN, YAP, and IL-6 expression in tumor tissues. Results: As indicated by PCR, Western blotting, and immunohistochemistry, POSTN, YAP, and IL-6 presented higher expression in LC tissues than in adjacent counterparts. In cell experiments, the cloning rate of LC cells decreased and the apoptosis rate increased after DHA intervention, with 160 μmol/L DHA contributing to the most significant effect on LC activity inhibition. Furthermore, DHA-intervened cells exhibited markedly reduced POSTN, YAP, and IL-6 levels. Finally, the tumorigenesis experiment in nude mice showed inhibited tumor growth after DHA administration. And consistently, the expressions of POSTN, YAP, and IL-6 in living tumors decreased. Conclusions: DHA can inhibit POSTN/YAP/IL-6 transduction, accelerate LC cell apoptosis, and alleviate the malignant progression of LC.
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- 2024
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15. Investigation on the fracture mechanics characteristics and crack initiation of deep dense shale
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Xiao, Ming-Li, Xie, Hong-Qiang, Feng, Gan, He, Qiang, Liu, Huai-Zhong, and Zhuo, Li
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- 2024
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16. Change of Flavonoid Content in Wheatgrass in a Historic Collection of Wheat Cultivars
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Chu-Yang Wang, Xiao-Ming Li, Han-Xiao Du, Yan Yan, Zhong-Zhong Chen, Chen-Xi Zhang, Xin-Bo Yan, Shui-Yuan Hao, and Jin-Ying Gou
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wheatgrass ,antioxidant activity ,flavonoids ,powdery mildew ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Wheatgrass is recognized for its nutritional and medicinal properties, partly attributed to its flavonoid content. The objective of this study was to assess the flavonoid content and antioxidant properties of wheatgrass obtained from a wide range of 145 wheat cultivars, which included Chinese landraces (CL), modern Chinese cultivars (MCC), and introduced modern cultivars (IMC). The flavonoids were extracted using a solution of 80% methanol, and their content was evaluated using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). The results revealed the assessed cultivars showed significant variation in their total flavonoid content (TFC), with MCCs generally having higher amounts compared to CLs. PCA analysis demonstrated clear variations in flavonoid profiles between different cultivar groups, emphasizing the evolutionary inconsistencies in wheat breeding. The antioxidant assays, ABTS, DPPH, and FRAP, exhibited robust abilities for eliminating radicals, which were found to be directly associated with the amounts of flavonoids. In addition, this study investigated the correlation between the content of flavonoids and the ability to resist powdery mildew in a collection of mutated wheat plants. Mutants exhibiting heightened flavonoid accumulation demonstrated a decreased severity of powdery mildew, suggesting that flavonoids play a protective role against fungal infections. The results highlight the potential of wheatgrass as a valuable source of flavonoids that have antioxidant and protective effects. This potential is influenced by the genetic diversity and breeding history of wheatgrass. Gaining insight into these connections can guide future wheat breeding endeavors aimed at improving nutritional value and in strengthening disease resistance. The current finding provides critical information for developing wheatgrass with high flavonoid content and antioxidant activity.
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- 2024
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17. Elimination method of sliding blockage effect in discrete element simulation of rolling stone based on discrete fracture network and damping joint model
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Zhou, You, Liu, Huai-Zhong, Xie, Hong-Qiang, Zhuo, Li, Xiao, Ming-Li, He, Jiang-Da, Pei, Jian-Liang, and Xu, Guo-Wen
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- 2024
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18. Antibacterial Polyketides from the Deep-Sea Cold-Seep-Derived Fungus Talaromyces sp. CS-258
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Zhenger Wu, Xiao-Ming Li, Sui-Qun Yang, Bin-Gui Wang, and Xin Li
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antibacterial activity ,fungal polyketides ,cold-seep-derived fungus ,Talaromyces sp. ,Biology (General) ,QH301-705.5 - Abstract
Thirty-two fungal polyketide derivatives, including eleven new compounds, namely (3R,5′R)-5-hydroxytalaroflavone (1), talaroisochromenols A–C (3, 5, and 11), (8R,9R,10aR)-5-hydroxyaltenuene (13), (8R,9R,10aS)-5-hydroxyaltenuene (14), (8R,9S,10aR)-5-hydroxyaltenuene (15), nemanecins D and E (25 and 26), 2,5-dimethyl-8-iodochromone (27), and talarofurolactone A (29), together with one new naturally occurring but previously synthesized metabolite, 6-hydroxy-4-methoxycoumarin (28), were isolated and identified from the deep-sea cold-seep-derived fungus Talaromyces sp. CS-258. Among them, racemic ((±)-11) or epimeric (13–15, 25, and 26) mixtures were successfully separated by chiral or gradient elution HPLC. Meanwhile, compound 27 represents a rarely reported naturally occurring iodinated compound. Their planar structures as well as absolute configurations were determined by extensive analysis via NMR, MS, single-crystal X-ray diffraction, Mosher’s method, and ECD or NMR calculation (with DP4+ probability analysis). Possible biosynthetic routes of some isolated compounds, which are related to chromone or isochromone biosynthetic pathways, were put forward. The biological analysis results revealed that compounds 7, 9, 10, 18–22, 24, 30, and 31 showed broad-spectrum antibacterial activities against several human and aquatic pathogens with MIC ranges of 0.5–64 μg/mL.
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- 2024
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19. Wave Attenuation by Sea Ice in the Arctic Marginal Ice Zone Observed by Spaceborne SAR
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Bing Qing Huang and Xiao‐Ming Li
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ocean wave ,sea ice ,SAR ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Attenuation of ocean waves by ice is a crucial process of the interaction between waves and sea ice in marginal ice zone (MIZ), while such interaction can contribute to the retreating of sea ice in the Arctic. Based on the retrieved two‐dimensional ocean wave spectra by spaceborne Synthetic Aperture Radar, we investigated the attenuation of ocean waves in the MIZ in Svalbard and Greenland. The results show that the energy attenuation rate ranges from 0.126 × 10−4/m to 0.618 × 10−4/m. Quantitative analysis suggests that the attenuation rate is significantly related to wave height and peak wave period of coming waves. It is further found that the waves decay faster in the area with ice thickness exceeding 0.5 m. We compared the derived wave attenuation rates in the present study with those in previous studies based on in situ measurements, which reveals that waves are becoming less attenuated by sea ice in the Arctic.
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- 2023
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20. Fibulin2: a negative regulator of BMSC osteogenic differentiation in infected bone fracture healing
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Shi-Dan Li, Wei Xing, Shao-Chuan Wang, You-Bin Li, Hao Jiang, Han-Xuan Zheng, Xiao-Ming Li, Jing Yang, De-Bin Guo, Xiao-Yu Xie, Ren-Qing Jiang, Chao Fan, Lei Li, Xiang Xu, and Jun Fei
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Medicine ,Biochemistry ,QD415-436 - Abstract
Bone fracture: Identifying a protein that hinders repair during infection A protein that is overexpressed during bone fracture infection blocks a key signaling pathway and prevents bone repair. Infection following bone fracture remains a leading cause of delayed or unsuccessful healing. Stem cells from bone marrow are the main source of osteoblasts, bone-forming cells necessary for healthy bone regeneration and repair. Infection causes disruption to stem cell function and hinders bone healing, but the exact mechanisms involved remain unclear. In experiments on human tissue samples and a mouse model, Jun Fei and Xiang Xu at the Army Medical University in Chongqing, China, and co-workers examined the role of the fibulin2 protein in infected bone fractures. Fibulin2 is overexpressed in infected tissues, and the protein suppresses stem cell differentiation into osteoblasts by deactivating a key signaling pathway. Blocking fibulin2 in mice models restored bone formation.
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- 2023
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21. Molecular and cellular evolution of the amygdala across species analyzed by single-nucleus transcriptome profiling
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Bin Yu, Qianqian Zhang, Lin Lin, Xin Zhou, Wenji Ma, Shaonan Wen, Chunyue Li, Wei Wang, Qian Wu, Xiaoqun Wang, and Xiao-Ming Li
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Cytology ,QH573-671 - Abstract
Abstract The amygdala, or an amygdala-like structure, is found in the brains of all vertebrates and plays a critical role in survival and reproduction. However, the cellular architecture of the amygdala and how it has evolved remain elusive. Here, we generated single-nucleus RNA-sequencing data for more than 200,000 cells in the amygdala of humans, macaques, mice, and chickens. Abundant neuronal cell types from different amygdala subnuclei were identified in all datasets. Cross-species analysis revealed that inhibitory neurons and inhibitory neuron-enriched subnuclei of the amygdala were well-conserved in cellular composition and marker gene expression, whereas excitatory neuron-enriched subnuclei were relatively divergent. Furthermore, LAMP5 + interneurons were much more abundant in primates, while DRD2 + inhibitory neurons and LAMP5 + SATB2 + excitatory neurons were dominant in the human central amygdalar nucleus (CEA) and basolateral amygdalar complex (BLA), respectively. We also identified CEA-like neurons and their species-specific distribution patterns in chickens. This study highlights the extreme cell-type diversity in the amygdala and reveals the conservation and divergence of cell types and gene expression patterns across species that may contribute to species-specific adaptations.
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- 2023
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22. Light from space illuminating the polar silk road
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Xiao-Ming Li, Yujia Qiu, Yacheng Wang, Bingqing Huang, Haiming Lu, Min Chu, Han Fu, and Fengming Hui
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arctic ,northern sea route ,earth observation ,digital earth ,sustainable development ,Mathematical geography. Cartography ,GA1-1776 - Abstract
The rapid decline of Arctic sea ice has been reminding us the significant impacts caused by global warming. However, the other side of the coin is that this opens a window to utilize the Arctic sea routes in the summer seasons, bringing remarkable economic benefits for ocean transportation between Asia and Europe. However, commercial vessels with low ice classes must tackle substantial environmental challenges in the Arctic sea routes, particularly those caused by variable sea ice, even in the melting seasons. Therefore, the science-based support for shipping safety in the Arctic sea routes is being given more prominence. Emerging satellite remote sensing technology plays a critical role in environmental monitoring in the Arctic. This paper reviews state-of-the-art satellite observations on monitoring sea ice and potential applications on supporting shipping activities in the Arctic Ocean. Moreover, we introduced a recently developed system based on satellite observations to support the safe transportation of Chinese cargo vessels in the Arctic northern sea route, demonstrating the efforts by both the science and business communities to promote the development of the polar silk road.
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- 2022
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23. Development of a texture evaluation system for winter jujube (Ziziphus jujuba ‘Dongzao’)
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Xia-bing KONG, Min XU, Hao-liang WAN, Ling-xi HAN, Xiao-li LIU, Qing-jun LI, Bian-qing HAO, Shao-jun ZHANG, Xiao-ming LI, Yi-hui LIU, and Ji-yun NIE
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winter jujube ,texture ,TPA ,evaluation ,representative indices ,Agriculture (General) ,S1-972 - Abstract
Winter jujube (Ziziphus jujuba ‘Dongzao’) is an excellent late maturing variety of fresh-eating jujube in China. Fruit texture is an important indicator of sensory quality. To investigate the correlations among texture indices and establish an evaluation system for winter jujube texture, we used the TMS-Touch instrument to perform a texture profile analysis (TPA) on 1 150 winter jujubes from three major producing areas in China. Eight indices and their best-fit distribution were obtained, including fracture (Pearson), hardness (InvGauss), adhesive force (Weibull), adhesiveness (LogLogistic), cohesiveness (LogLogistic), springiness (BetaGeneral), gumminess (InvGauss), and chewiness (InvGauss). Based on the best-fit distribution curves, each index was divided into five grades (lower, low, medium, high and higher) by the 10th, 30th, 70th and 90th percentiles. Among the texture indices, 82% of the correlation coefficients were highly significant (P
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- 2022
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24. Improvement of size effect simulation based on an energy-balanced exponential softening bond model and fracture energy regularization
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Wang, Tao, Liu, Huai-Zhong, Xiao, Ming-Li, Zhuo, Li, Xie, Hong-Qiang, and He, Jiang-Da
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- 2023
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25. Automatic Extraction of Marine Aquaculture Areas Based on the Semantic Segmentation Network from GF-3 SAR Data.
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Xiaomeng Geng, Xiao-Ming Li, and Tong Jia
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- 2022
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26. Generation of Nonlinear Internal Waves Around Hainan Island.
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Tong Jia, Xiao-Ming Li, and Jianjun Liang
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- 2022
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27. Total Hip Arthroplasty with Robotic Arm Assistance for Precise Cup Positioning: A Case‐Control Study
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Dong‐hui Guo, Xiao‐ming Li, Shi‐qiang Ma, Yun‐chao Zhao, Chao Qi, and Yuan Xue
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cup positioning ,learning curve ,robot‐assisted surgery ,total hip arthroplasty ,Orthopedic surgery ,RD701-811 - Abstract
Abstract Objective To determine whether more precise cup positioning can be achieved with robot‐assisted total hip arthroplasty (THA) as compared to conventional THA. Methods In this study, between July 2019 and May 2021, 93 patients aged 23–75 years with osteonecrosis of the femoral head (ONFH) and adult developmental dysplasia of hip who underwent first hip surgery were included in the study. They were randomly assigned to either the robotic‐assisted THA group (n = 45) or the conventional THA group (n = 48). After the operation, all patients were given routine rapid rehabilitation guidance. The duration of operation was recorded to estimate the learning curve through cumulative summation analysis. We compared the demographics, duration of operation, cup positioning, leg length discrepancy, hip offset, and Harris Hip Score between robot‐assisted THA and manual THA. Precision in the positioning of the acetabular prosthesis using the MAKO system was also compared between the two groups. Results The mean duration of operation for the robot‐assisted THA group was 91.37 ± 17.34 min (range: 63 to 135 min), which was significantly higher than that for the conventional THA group. When the number of procedures was increased to 13, the duration of operation in the robot‐assisted group decreased significantly and gradually became stable. In terms of duration of operation, robot‐assisted THA was associated with a learning curve of 13 cases. The mean amount of bleeding in the robot‐assisted THA group was not significantly different from that in conventional THA group (328 ± 210 ml vs 315 ± 205 ml) (p = 0.741). There was no significant difference in the proportion of prostheses located within Lewinnek's safe zone between robot‐assisted THA group and conventional THA group (69.81% vs 64.41%). The leg length discrepancy (LLD) was significantly smaller in the robot‐assisted THA group than in the conventional THA group (p
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- 2022
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28. Inclusion and mechanical properties of ODS-RAFM steels with Y, Ti, and Zr fabricated by melting
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Guo-xing Qiu, Xu-li Wei, Chong Bai, De-jun Miao, Lei Cao, and Xiao-ming Li
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ODS-RAFM ,Zr ,Ti ,Inclusion ,Tensile properties ,Nuclear engineering. Atomic power ,TK9001-9401 - Abstract
Two groups of oxide dispersion–strengthened reduced-activation ferritic/martensitic steels (A and B) were prepared by adding Y, Ti, and Zr into steels through vacuum induction melting to investigate the inclusions, microstructures, mechanical properties of the alloys. Results showed that particles with Y, Ti, and Zr easily formed. Massive, Zr-rich inclusions were found in B steel. Density of micron inclusions in A steel was 1.42 × 1014 m−3, and density of nanoparticles was 3.61 × 1016 m−3. More and finer MX carbides were found in steel tempered at 650 °C, and yield strengths (YS) of A and B steel were 714±2 and 664±3.5 MPa. Thermomechanical processing (TMP) retained many dislocations, which improved the mechanical properties. YSs of A and B treated by TMP were 725±3 and 683±4 MPa. The existence of massive Zr-rich inclusions in B steels interrupted the continuity of the matrix and produced microcracks (fracture), which caused a reduction in mechanical properties. The presence of fine prior austenite grain size and inclusions was attributed to the low DBTTs of the A steels; DBTTs of A650 and A700 alloy were −79 and −65 °C. Tempering temperature reduction and TMP are simple, readily useable methods that can lead to a superior balance of strength and impact toughness in industry applications.
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- 2022
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29. Structural insights into human brain–gut peptide cholecystokinin receptors
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Yu Ding, Huibing Zhang, Yu-Ying Liao, Li-Nan Chen, Su-Yu Ji, Jiao Qin, Chunyou Mao, Dan-Dan Shen, Lin Lin, Hao Wang, Yan Zhang, and Xiao-Ming Li
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Cytology ,QH573-671 - Abstract
Abstract The intestinal hormone and neuromodulator cholecystokinin (CCK) receptors CCK1R and CCK2R act as a signaling hub in brain–gut axis, mediating digestion, emotion, and memory regulation. CCK receptors exhibit distinct preferences for ligands in different posttranslational modification (PTM) states. CCK1R couples to Gs and Gq, whereas CCK2R primarily couples to Gq. Here we report the cryo-electron microscopy (cryo-EM) structures of CCK1R–Gs signaling complexes liganded either by sulfated cholecystokinin octapeptide (CCK-8) or a CCK1R-selective small-molecule SR146131, and CCK2R–Gq complexes stabilized by either sulfated CCK-8 or a CCK2R-selective ligand gastrin-17. Our structures reveal a location-conserved yet charge-distinct pocket discriminating the effects of ligand PTM states on receptor subtype preference, the unique pocket topology underlying selectivity of SR146131 and gastrin-17, the conformational changes in receptor activation, and key residues contributing to G protein subtype specificity, providing multiple structural templates for drug design targeting the brain–gut axis.
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- 2022
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30. Experimental and numerical study on the mechanical properties of compressively precracked sandstone repaired by grouting
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Zhang, Guang-Sen, Xiao, Ming-Li, Zhang, Ya-Dong, Liu, Huai-Zhong, Zhuo, Li, Xie, Hong-Qiang, and He, Jiang-Da
- Published
- 2022
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31. Identification of mitochondria-related key gene and association with immune cells infiltration in intervertebral disc degeneration
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Wei Guo, Kun Mu, Wen-Shuai Li, Shun-Xing Gao, Lin-Feng Wang, Xiao-Ming Li, and Jian-Yong Zhao
- Subjects
MFN2 ,NLRP3 inflammasome ,immune cells infiltration ,intervertebral disc degeneration ,signature genes ,Genetics ,QH426-470 - Abstract
Intervertebral disc (IVD) degeneration and its inflammatory microenvironment can result in discogenic pain, which has been shown to stem from the nucleus pulposus (NP). Increasing evidence suggests that mitochondrial related genes are strictly connected to cell functionality and, importantly, it can regulate cell immune activity in response to damaged associated signals. Therefore, identification of mitochondria related genes might offer new diagnostic markers and therapeutic targets for IVD degeneration. In this study, we identified key genes involved in NP tissue immune cell infiltration during IVD degeneration by bioinformatic analysis. The key modules were screened by weighted gene co-expression network analysis (WCGNA). Characteristic genes were identified by random forest analysis. Then gene set enrichment analysis (GSEA) was used to explore the signaling pathways associated with the signature genes. Subsequently, CIBERSORT was used to classify the infiltration of immune cells. Function of the hub gene was confirmed by PCR, Western blotting and ELISA. Finally, we identified MFN2 as a crucial molecule in the process of NP cell pyroptosis and NLRP3 inflammasome activation. We speculate that the increased MFN2 expression in NP tissue along with the infiltration of CD8+ T cells, NK cell and neutrophils play important roles in the pathogenesis of IVD degeneration.
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- 2023
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32. Sleep patterns and potential risk factors for disturbed sleep quality in patients after surgery for infective endocarditis
- Author
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Xiang-Ming Hu, Wen-Ting Wei, De-Yi Huang, Cai-Di Lin, Fen Lu, Xiao-Ming Li, Huo-Sheng Liao, Zhi-Hong Yu, Xiao-Ping Weng, Shi-Bin Wang, Cai-Lan Hou, and Fu-Jun Jia
- Subjects
Infective endocarditis ,Sleep quality ,Actigraphy ,The Pittsburgh sleep quality index (PSQI) ,The Epworth sleepiness scale (ESS) ,Surgery ,RD1-811 ,Anesthesiology ,RD78.3-87.3 - Abstract
Abstract Background The current study aimed to investigate the sleep quality of patients after valve replacement surgery due to infective endocarditis and identify risk factors for disturbed sleep post hospitalisation. Methods Eighty patients were assessed postoperatively using subjective scale measures, the Pittsburgh sleep quality index (PSQI) and the Epworth sleepiness scale, and an objective measure, actigraphy. Scale measures were assessed approximately 2 weeks and 6 months after surgery. Actigraphy monitoring was performed for 2 consecutive weeks during hospitalisation. Logistic regression was used to identify risk factors for disturbed sleep. Results The study population (n = 80) had an average age of 42.8 ± 14.2 years, and 67.5% were male. The median sleep efficiency was 85.3% in week 1 and 86.8% in week 2. The frequency of awakenings was significantly higher in week 1 (20.0 times vs. 19.3 times, p = 0.017). The scale measures showed significant improvement in sleep by 6 months after surgery compared to that during hospitalisation. Multivariable logistic regression analysis suggested that the possible risk factors for disturbed sleep 6 months after surgery included age (OR = 1.479, 95%CI 1.140–1.920) and a few parameters of early postoperative disturbed sleep quality (PSQI: OR = 2.921, 95%CI 1.431–5.963; sleep efficiency: OR = 0.402, 95%CI 0.206–0.783; and average duration of awakenings: OR = 0.006, 95%CI 0.000–0.827). Conclusions Disturbed sleep quality was witnessed in postoperative patients during hospitalisation and up to 6 months after surgery. Over time, the patients’ sleep quality improved significantly. Age and a few early postoperative sleep quality variables were risk factors for disturbed sleep 6 months after surgery.
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- 2022
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33. A creep model coupling moisture and mechanical damage for water-bearing concrete
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Zheng, Zhao-Qiang, Liu, Huai-Zhong, Xiao, Ming-Li, He, Jiang-Da, Xie, Hong-Qiang, and Zhuo, Li
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- 2022
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34. 3D rock physics template-based probabilistic estimation of tight sandstone reservoir properties.
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Hao-Jie Pan, Chao Wei, Xin-Fei Yan, Xiao-Ming Li, Zhi-Fang Yang, Zhi-Xian Gui, and Shu-Xian Liu
- Subjects
BULK modulus ,POROSITY ,MODULUS of rigidity ,ELASTICITY ,ACOUSTIC models - Abstract
Quantitative prediction of reservoir properties (e.g., gas saturation, porosity, and shale content) of tight reservoirs is of great significance for resource evaluation and well placements. However, the complex pore structures, poor pore connectivity, and uneven fluid distribution of tight sandstone reservoirs make the correlation between reservoir parameters and elastic properties more complicated and thus pose a major challenge in seismic reservoir characterization. We have developed a partially connected double porosity model to calculate elastic properties by considering the pore structure and connectivity, and to analyze these factors' influences on the elastic behaviors of tight sandstone reservoirs. The modeling results suggest that the bulk modulus is likely to be affected by the pore connectivity coefficient, while the shear modulus is sensitive to the volumetric fraction of stiff pores. By comparing the model predictions with the acoustic measurements of the dry and saturated quartz sandstone samples, the volumetric fraction of stiff pores and the pore connectivity coefficient can be determined. Based on the calibrated model, we have constructed a 3D rock physics template that accounts for the reservoir properties' impacts on the P-wave impedance, S-wave impedance, and density. The template combined with Bayesian inverse theory is used to quantify gas saturation, porosity, clay content, and their corresponding uncertainties from elastic parameters. The application of well-log and seismic data demonstrates that our 3D rock physics template-based probabilistic inversion approach performs well in predicting the spatial distribution of high-quality tight sandstone reservoirs in southwestern China. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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35. Sea Sate and Sea Surface Wind Measurement by Spaceborne SAR in the Arctic Ocean.
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Bingqing Huang, Ke Wu, and Xiao-Ming Li
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- 2021
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36. Pan-Arctic ocean wind and wave data by spaceborne SAR
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Xiao-Ming Li, Ke Wu, and Bingqing Huang
- Subjects
arctic ,synthetic aperture radar (sar) ,ocean wind ,ocean wave ,Geography. Anthropology. Recreation ,Geology ,QE1-996.5 - Abstract
The Arctic is one of the most significant changing areas on the Earth under the climate change scenario. More regions in the Arctic are becoming ice-free oceans in the melting season or through the whole year. Therefore, ocean wind and wave, as the two most important parameters in the air–sea interface, are drawing significant attention to the Arctic Ocean. Scatterometer and radar altimeter are the two traditional remote sensing instruments for ocean wind and wave observations, while the former is limited by coarse spatial resolution and the latter has small spatial coverage. Wind and wave data in high spatial resolution and wide coverage by synthetic aperture radar (SAR) are currently lacking in the Arctic Ocean. We developed an ocean wind and wave dataset by Sentinel-1 SAR in the pan-Arctic Ocean (above 60°N), covering January 2017 to May 2021. By comparing with sea surface wind speed data of scatterometer, the SAR-retrieved wind data achieve an accuracy of 1.23 m/s, in terms of root mean square error (RMSE). Compared with significant wave height data of radar altimeter, the SAR retrievals have an RMSE of 0.66 m. The data records are in the standard NetCDF-4 format. The dataset is publicly available at: http://www.dx.doi.org/10.11922/sciencedb.00834.
- Published
- 2022
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37. Preoperative prediction of early recurrence of HBV-related hepatocellular carcinoma (≤5 cm) by visceral adipose tissue index
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Zong-qian Wu, Jie Cheng, Xi-xi Xiao, Hua-rong Zhang, Jian Wang, Juan Peng, Chen Liu, Ping Cai, and Xiao-ming Li
- Subjects
visceral adipose tissue ,HBV ,HCC ,early recurrence ,abdominal adipose tissue ,computed tomography ,Surgery ,RD1-811 - Abstract
BackgroundThis study aimed to investigate whether visceral adipose tissue index (VATI) is a significant risk factor for the early recurrence (ER) of HBV-related hepatocellular carcinoma (HCC) (≤5 cm) after hepatectomy.MethodsThe recruited cohort patients who were positive for hepatitis B virus, presented with surgically confirmed HCC (≤5 cm) from Army Medical University (internal training cohort: n = 192) and Chongqing Medical University (external validation group: n = 46). We measured VATI, subcutaneous adipose tissue index (SATI) via computed tomography (CT). ER was defined as recurrence within 2 years after hepatectomy. The impact of parameters on outcome after hepatectomy for HCC was analyzed.ResultsUnivariate analysis showed that alpha-fetoprotein levels (p = 0.044), body mass index (BMI) (p
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- 2023
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38. Retrieval of Sea Surface Wind Speed by Spaceborne SAR Based on Machine Learning.
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Xiao-Ming Li
- Published
- 2020
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39. FveARF2 negatively regulates fruit ripening and quality in strawberry
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Shan-na Yi, Jian-xin Mao, Xin-yu Zhang, Xiao-ming Li, Zhi-hong Zhang, and He Li
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strawberry ,FveARF2 ,fruit ripening ,quality ,potassium ,Plant culture ,SB1-1110 - Abstract
Auxin response factors (ARFs) are transcription factors that play important roles in plants. ARF2 is a member of the ARF family and participates in many plant growth and developmental processes. However, the role of ARF2 in strawberry fruit quality remains unclear. In this study, FveARF2 was isolated from the woodland strawberry ‘Ruegen’ using reverse transcription-polymerase chain reaction (RT-PCR), which showed that FveARF2 expression levels were higher in the stem than in other organs of the ‘Ruegen’ strawberry. Moreover, FaARF2 was higher in the white fruit stage of cultivated strawberry fruit than in other stage. Subcellular localization analysis showed that FveARF2 is located in the nucleus, while transcriptional activation assays showed that FveARF2 inhibited transcription in yeast. Silencing FveARF2 in cultivated strawberry fruit revealed earlier coloration and higher soluble solid, sugar, and anthocyanin content in the transgenic fruit than in the control fruit, overexpression of FveARF2 in strawberry fruit delayed ripening and lower soluble solid, sugar, and anthocyanin content compared to the control fruit. Gene expression analysis indicated that the transcription levels of the fruit ripening genes FaSUT1, FaOMT, and FaCHS increased in FveARF2-RNAi fruit and decreased in FveARF2-OE fruit, when compared with the control. Furthermore, yeast one-hybrid (Y1H) and GUS activity experiments showed that FveARF2 can directly bind to the AuxRE (TGTCTC) element in the FaSUT1, FaOMT, and FaCHS promoters in vitro and in vivo. Potassium ion supplementation improved the quality of strawberry fruit, while silencing FveARF2 increased potassium ion content in transgenic fruit. The Y1H and GUS activity experiments also confirmed that FveARF2 could directly bind to the promoter of FveKT12, a potassium transporter gene, and inhibited its expression. Taken together, we found that FveARF2 can negatively regulate strawberry fruit ripening and quality, which provides new insight for further study of the molecular mechanism of strawberry fruit ripening.
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- 2022
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40. Remotely sensed big data for the oceans and polar regions
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Xiao-Ming Li
- Subjects
Geography. Anthropology. Recreation ,Geology ,QE1-996.5 - Published
- 2022
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41. Exosomal miR-365a-5p derived from HUC-MSCs regulates osteogenesis in GIONFH through the Hippo signaling pathway
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Ming-jie Kuang, Kai-hui Zhang, Jie Qiu, An-bang Wang, Wen-wen Che, Xiao-ming Li, Dong-li Shi, and Da-Chuan Wang
- Subjects
exosomes ,GIONFH ,osteogenesis ,HUC-MSCs ,Hippo signaling pathway ,Therapeutics. Pharmacology ,RM1-950 - Abstract
The pathogenesis of glucocorticoid (GC)-induced osteonecrosis of the femoral head (GIONFH) is still disputed, and abnormal bone metabolism caused by GCs may be an important factor. In vitro, Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2′-deoxyuridine (EdU) staining were used to evaluate cellular proliferation, and western blotting was used to investigate osteogenesis. In vivo, we used micro-computed tomography (micro-CT), H&E staining, Masson staining, and immunohistochemistry (IHC) analysis to evaluate the impact of exosomes. In addition, the mechanism by which exosomes regulate osteogenesis through the miR-365a-5p/Hippo signaling pathway was investigated using RNA sequencing (RNA-seq), luciferase reporter assays, fluorescence in situ hybridization (FISH), and western blotting. The results of western blotting verified that the relevant genes in osteogenesis, including BMP2, Sp7, and Runx2, were upregulated. RNA-seq and qPCR of the exosome and Dex-treated exosome groups showed that miR-365a-5p was upregulated in the exosome group. Furthermore, we verified that miR-365a-5p promoted osteogenesis by targeting SAV1. Additional in vivo experiments revealed that exosomes prevented GIONFH in a rat model, as shown by micro-CT scanning and histological and IHC analysis. We concluded that exosomal miR-365a-5p was effective in promoting osteogenesis and preventing the development of GIONFH via activation of the Hippo signaling pathway in rats.
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- 2021
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42. A flexible ultrasensitive optoelectronic sensor array for neuromorphic vision systems
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Qian-Bing Zhu, Bo Li, Dan-Dan Yang, Chi Liu, Shun Feng, Mao-Lin Chen, Yun Sun, Ya-Nan Tian, Xin Su, Xiao-Mu Wang, Song Qiu, Qing-Wen Li, Xiao-Ming Li, Hai-Bo Zeng, Hui-Ming Cheng, and Dong-Ming Sun
- Subjects
Science - Abstract
To emulate nature biological processing, highly-integrated ultra-sensitive artificial neuromorphic system is highly desirable. Here, the authors report flexible sensor array of 1024 pixels using combination of carbon nanotubes and perovskite QDs as active matetials, achieving highly responsive device for reinforcement learning.
- Published
- 2021
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43. Diketopiperazine Alkaloids and Bisabolene Sesquiterpenoids from Aspergillus versicolor AS-212, an Endozoic Fungus Associated with Deep-Sea Coral of Magellan Seamounts
- Author
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Yu-Liang Dong, Xiao-Ming Li, Xiao-Shan Shi, Yi-Ran Wang, Bin-Gui Wang, and Ling-Hong Meng
- Subjects
diketopiperazine ,Aspergillus versicolor ,deep-sea coral ,endophytic fungus ,antimicrobial activity ,Biology (General) ,QH301-705.5 - Abstract
Two new quinazolinone diketopiperazine alkaloids, including versicomide E (2) and cottoquinazoline H (4), together with ten known compounds (1, 3, and 5–12) were isolated and identified from Aspergillus versicolor AS-212, an endozoic fungus associated with the deep-sea coral Hemicorallium cf. imperiale, which was collected from the Magellan Seamounts. Their chemical structures were determined by an extensive interpretation of the spectroscopic and X-ray crystallographic data as well as specific rotation calculation, ECD calculation, and comparison of their ECD spectra. The absolute configurations of (−)-isoversicomide A (1) and cottoquinazoline A (3) were not assigned in the literature reports and were solved in the present work by single-crystal X-ray diffraction analysis. In the antibacterial assays, compound 3 exhibited antibacterial activity against aquatic pathogenic bacteria Aeromonas hydrophilia with an MIC value of 18.6 μM, while compounds 4 and 8 exhibited inhibitory effects against Vibrio harveyi and V. parahaemolyticus with MIC values ranging from 9.0 to 18.1 μM.
- Published
- 2023
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44. Vicarious Radiometric Calibration of the Multispectral Imager Onboard SDGSAT-1 over the Dunhuang Calibration Site, China
- Author
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Zhenzhen Cui, Chao Ma, Hao Zhang, Yonghong Hu, Lin Yan, Changyong Dou, and Xiao-Ming Li
- Subjects
vicarious calibration ,reflectance-based method ,irradiance-based method ,Dunhuang site ,SDGSAT-1 ,Science - Abstract
The multispectral imager (MII), onboard the Sustainable Development Science Satellite 1 (SDGSAT-1), performs detailed terrestrial change detection and coastal monitoring. SDGSAT-1 was launched at 2:19 UTC on 5 November 2021, as the world’s first Earth science satellite to serve the United Nations 2030 Sustainable Development Agenda. A vicarious radiometric calibration experiment was conducted at the Dunhuang calibration site (Gobi Desert, China) on 14 December 2021. In-situ measurements of ground reflectance, aerosol optical depth (AOD), total columnar water vapor, radiosonde data, and diffuse-to-global irradiance (DG) ratio were performed to predict the top-of-atmosphere radiance by the reflectance-, irradiance-, and improved irradiance-based methods using the moderate resolution atmospheric transmission model. The MII calibration coefficients were calculated by dividing the top-of-atmosphere radiance by the average digital number value of the image. The radiometric calibration coefficients calculated by the three calibration methods were reliable (average relative differences: 2.20% (reflectance-based vs. irradiance-based method) and 1.43% (reflectance-based vs. improved irradiance-based method)). The total calibration uncertainties of the reflectance-, irradiance-, and improved irradiance-based methods were 2.77–5.23%, 3.62–5.79%, and 3.50–5.23%, respectively. The extra DG ratio measurements in the latter two methods did not improve the calibration accuracy for AODs ≤ 0.1. The calibrated MII images were verified using Landsat-8 Operational Land Imager (OLI) and Sentinel-2A MultiSpectral Instrument (MSI) images. The retrieved ground reflectances of the MII over different surface types were cross-compared with those of OLI and MSI using the FAST Line-of-sight Atmospheric Analysis of Hypercubes software. The MII retrievals differed by
- Published
- 2023
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45. Constructing a Low–Cost Si–NSs@C/NG Composite by a Ball Milling–Catalytic Pyrolysis Method for Lithium Storage
- Author
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Qi Zhang, Ning-Jing Song, Can-Liang Ma, Yun Zhao, Yong Li, Juan Li, Xiao-Ming Li, Qing-Qiang Kong, and Cheng-Meng Chen
- Subjects
silicon nanosheet ,nitrogen–doped graphene ,catalytic pyrolysis ,embedded structure ,lithium–ion battery ,Organic chemistry ,QD241-441 - Abstract
Silicon–based composites are promising candidates as the next–generation anode materials for high–performance lithium–ion batteries (LIBs) due to their high theoretical specific capacity, abundant reserves, and reliable security. However, expensive raw materials and complicated preparation processes give silicon carbon anode a high price and poor batch stability, which become a stumbling block to its large–scale practical application. In this work, a novel ball milling–catalytic pyrolysis method is developed to fabricate a silicon nanosheet@amorphous carbon/N–doped graphene (Si–NSs@C/NG) composite with cheap high–purity micron–size silica powder and melamine as raw materials. Through systematic characterizations such as XRD, Raman, SEM, TEM and XPS, the formation process of NG and a Si–NSs@C/NG composite is graphically demonstrated. Si–NSs@C is uniformly intercalated between NG nanosheets, and these two kinds of two–dimensional (2D) materials are combined in a surface–to–surface manner, which immensely buffers the stress changes caused by volume expansion and contraction of Si–NSs. Attributed to the excellent electrical conductivity of graphene layer and the coating layer, the initial reversible specific capacity of Si–NSs@C/NG is 807.9 mAh g−1 at 200 mA g−1, with a capacity retention rate of 81% in 120 cycles, exhibiting great potential for application as an anode material for LIBs. More importantly, the simple and effective process and cheap precursors could greatly reduce the production cost and promote the commercialization of silicon/carbon composites.
- Published
- 2023
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46. Antibacterial Indole Diketopiperazine Alkaloids from the Deep-Sea Cold Seep-Derived Fungus Aspergillus chevalieri
- Author
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Li-Hong Yan, Feng-Yu Du, Xiao-Ming Li, Sui-Qun Yang, Bin-Gui Wang, and Xin Li
- Subjects
Aspergillus chevalieri ,deep-sea cold seep ,indole diketopiperazine ,antibacterial activity ,Biology (General) ,QH301-705.5 - Abstract
A large body of fungal secondary metabolites has been discovered to exhibit potent antibacterial activities with distinctive mechanisms and has the potential to be an untapped resource for drug discovery. Here, we describe the isolation and characterization of five new antibacterial indole diketopiperazine alkaloids, namely 24,25-dihydroxyvariecolorin G (1), 25-hydroxyrubrumazine B (2), 22-chloro-25-hydroxyrubrumazine B (3), 25-hydroxyvariecolorin F (4), and 27-epi-aspechinulin D (5), along with the known analogue neoechinulin B (6) from a fungal strain of deep-sea cold seep-derived Aspergillus chevalieri. Among these compounds, 3 and 4 represented a class of infrequently occurring fungal chlorinated natural products. Compounds 1–6 showed inhibitory activities against several pathogenic bacteria with MIC values ranging from 4 to 32 μg/mL. It was revealed that compound 6 could induce structural damage to the Aeromonas hydrophila cells based on the observation by scanning electron microscopy (SEM), which led to the bacteriolysis and death of A. hydrophila, suggesting that neoechinulin B (6) might be a potential alternative to novel antibiotics development.
- Published
- 2023
- Full Text
- View/download PDF
47. AOD Derivation from SDGSAT-1/GLI Dataset in Mega-City Area
- Author
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Ning Wang, Yonghong Hu, Xiao Ming Li, Chuanli Kang, and Lin Yan
- Subjects
nighttime aerosol ,aerosol optical depth ,SDGSAT-1/GLI ,night light ,urban ,Science - Abstract
Aerosol optical depth (AOD) is the key parameter for determining the aerosol radiative effects and air quality variation. It is important to quantify nighttime aerosols using satellite-based night light images to understand their diurnal variations. This study selected high-resolution low light images from the Glimmer Imager (GLI) aboard the SDGSAT-1 satellite to examine spatial–temporal changes in night light emitted from the urban surface of Beijing. The radiance observed by SDGSAT-1/GLI was used to discern the AOD changes using the radiance background method (RB) and standard deviation method (SD) based on the characterization of the radiance from artificial light sources. Cloud cleaning processes were conducted to reduce the influence of the cloud cover in the glimmer images of the derived AOD. The results showed that there are good consistencies between the derived AOD results from the remote sensing and nighttime site observations. The radiance background method is better than the standard deviation method for deriving AOD using SDGSAT-1/GLI with the RMSE of its RB (0.0984) being greater than that of the SD (0.7653). The influence of moonlight, atmospheric absorption, and positioning errors on the results is briefly discussed. This paper shows that SDGSAT-1 can obtain relatively reliable night AOD values based on our investigations using the available satellite images taken in winter and spring, and that it has the potential to provide the scientific products of nighttime AOD.
- Published
- 2023
- Full Text
- View/download PDF
48. Doped Emitting Cesium Silver Halides as X‐Ray Scintillator with Fast Response Time, High Absorption Coefficient, and Light Yield
- Author
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Jia-Li Yao, Zi-Xu Zhang, Xiao-Qi Sun, Tong Chang, Jing-Fu Guo, Ke-Ke Huang, Hai-Bo Zeng, Da-Yang Wang, Wen-Sheng Yang, Ruo-Sheng Zeng, Xiao-Ming Li, and Ren-Guo Xie
- Subjects
Ag halides ,doping ,high light yield ,scintillators ,short decay time ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
Radioluminescence materials (scintillators) are widely investigated because of their potential application in many fields, such as medical imaging, security‐related techniques, and nondestructive inspection. However, the fabrication of scintillator materials with simultaneously fast response time, high absorption coefficient, and high light yield, as well as low toxicity is still a challenge. Herein, the synthesis of Cu(I)‐doped Cs2AgI3 single crystals (SCs) with a 1D crystal structure is presented. A bright blue‐green photoluminescence (PL) is observed after incorporating Cu+ into the Cs2AgI3 SCs under UV irradiation at room temperature. The PL quantum yield of the doped samples can reach up to 73% at a Cu+ concentration of 0.66%. Experimental and theoretical studies show that the blue‐green emission may originate from self‐trapped excitons, which is further verified by photophysical results from control experiments on pure Cs2AgI3 SCs. Upon X‐ray excitation, Cu‐doped SCs exhibit fast scintillation decay time (288 ns), high light yield (27 000 photons per MeV), and high absorption coefficient compared with the commercial product (CsI: Tl). These results suggest that Cu‐doped Cs2AgI3 is an ideal scintillator, which will be a promising candidate for potential application in dynamic real‐time imaging and radiation detection.
- Published
- 2021
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49. BACK ANALYSIS AND STABILITY PREDICTION OF SURROUNDING ROCK DURING EXCAVATION OF THE SHUANGJIANGKOU UNDERGROUND POWERHOUSE.
- Author
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LI, You, XIAO, Ming-Li, FENG, Gan, CAI, Ming-Guang, WU, Jia-Ming, PEI, Jian-Liang, and HE, Jiang-Da
- Subjects
- *
ARCHAEOLOGICAL excavations , *ROCKS , *ELASTIC modulus , *WATER power , *POISSON'S ratio - Abstract
The underground powerhouse of the Shuangjiangkou hydropower station is one of the largest caverns under construction in China, and its stability during construction is crucial for safe construction. To study the stability of the surrounding rock during excavation, the displacement and stress of the surrounding rock were monitored by multi-point displacement meters and bolt stress meters. Based on the monitoring data, the elastic modulus, Poisson's ratio, friction angle, and cohesion of surrounding rock were inversely analyzed by the PSO-BP algorithm. Then, the back-analyzed parameters were used to simulate the subsequent excavations and predict the stability of surrounding rock during the following construction. The analysis results show that the surrounding rocks were generally stable during the initial four stages of excavation, and the main factors affecting their stability were blasts and unfavorable geological structures, including the lamprophyre vein and the F1 fault. These unfavorable geological structures also significantly decrease the mechanical parameters of surrounding rock as demonstrated by back analysis, and the stability prediction results show that the omnibus bar cave and the tailrace tunnel were at the greatest risk of instability during the subsequent excavations. This study provides a practical analysis for engineering excavation of the underground caverns. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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50. Detection of Neural Activity of Brain Functional Site Based on Microwave Scattering Principle
- Author
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Jing-Ke Wang, Xing Jiang, Lin Peng, Xiao-Ming Li, Hong-Jin An, and Bao-Jian Wen
- Subjects
Microwave transmission ,dynamic dielectric ,phase detection ,SAR analysis ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
A method of detecting brain neural activity with the microwave transmission technology is presented in this paper. This method is based on the fact that the dielectric properties of brain functional site vary with the electrophysiological neural activity. The analysis of the uniform plane wave propagation of dynamic layered medium shows that the phase change of transmission coefficient (S-parameters) is consistent with the variation frequency of permittivity in the dynamic dielectric layer. A 3D head model was introduced to assign dynamic dielectric properties to the cerebral cortex by embedding a tissue piece in this head model. A six-element horn antenna array around the head model was designed, and two types of brain activity at various locations (visual cortex and auditory cortex) inside the head model has been discussed. The simulation results of microwave scattering in different directions show that forward scattering has better applicability. The frequency of the permittivity variation associated with the brain neuronal activity (10 Hz, 20 Hz) can be extracted from the phase variation on S-parameters. In addition, the specific absorption rate analysis ensures the safety of using the microwave in the design of human head detection systems.
- Published
- 2019
- Full Text
- View/download PDF
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