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The Spatial-Temporal Characteristics of Meteorological Disasters in the Southwest Region of Zhejiang Province during 1953-2022
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作者 Qi Zhang yifan wang +3 位作者 Zhidan Zhu Hongxia Shi Wenhao Yang Shujie Yuan 《Journal of Geoscience and Environment Protection》 2024年第3期16-27,共12页
Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang pro... Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang province, where also has experienced meteorological disasters including rainstorm and cold wave. Understanding the temporal-spatial characteristics of meteorological disasters is important for the local tourism and economic development. Based on the daily temperature and precipitation from 18 meteorological stations in the southwest of Zhejiang province during 1953-2022 and some statistical approaches, the temporal and spatial characteristics of meteorological disasters (Freezing, Rainstorm, Cold wave) are analyzed. The results indicate that 1) Rainstorm occurred frequently around the Liuchun lake, the frequency was about 8 times/a, it can also reach about 3 times/a in the other region. Freezing and cold wave (including strong cold wave and extremely cold wave) had the same spatial distribution as rainstorm, however, except for Liuchun lake, they occurred less than one time in the other regions;2) The trend of rainstorm had larger spatial difference, it increased in all the study area, but it increased more significantly around the study area than around Liuchun lake. Freezing was on the downtrend in the whole region, with 93.3% of the stations passed the 95% significant level. Cold wave also showed a declined trend, but it was insignificantly at most of the stations, only 33% of the stations passed the 90% significant level. Compared with cold wave, strong cold wave and extremely strong cold wave had weaker decline in all the regions. In general, from 1953 to 2022 rainstorm showed an increasing trend, it was the main meteorological disaster in the study area, cold wave displayed a decreasing trend, but it still occurred about 2 - 3 times/a in most regions. 展开更多
关键词 Southwest of Zhejiang Province RAINSTORM Cold Wave Spatial Distribution Trend Analysis
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Electrochemical reduction of carbon dioxide to produce formic acid coupled with oxidative conversion of biomass
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作者 Xi Liu yifan wang +2 位作者 Zhiwei Dai Daihong Gao Xuebing Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期705-729,共25页
Electrochemical reduction of CO_(2)(CO_(2)RR)has become a research hot spot in recent years in the context of carbon neutrality.HCOOH is one of the most promising products obtained by electrochemical reduction of CO_(... Electrochemical reduction of CO_(2)(CO_(2)RR)has become a research hot spot in recent years in the context of carbon neutrality.HCOOH is one of the most promising products obtained by electrochemical reduction of CO_(2) due to its high energy value as estimated by market price per energy unit and wide application in chemical industry.Biomass is the most abundant renewable resource in the natural world.Coupling biomass oxidative conversion with CO_(2)RR driven by renewable electricity would well achieve carbon negativity.In this work,we comprehensively reviewed the current research progress on CO_(2)RR to produce HCOOH and coupled system for conversion of biomass and its derivatives to produce value-added products.Sn-and Bi-based electrocatalysts are discussed for CO_(2)RR with regards to the structure of the catalyst and reaction mechanisms.Electro-oxidation reactions of biomass derived sugars,alcohols,furan aldehydes and even polymeric components of lignocellulose were reviewed as alternatives to replace oxygen evolution reaction(OER)in the conventional electrolysis process.It was recommended that to further improve the efficiency of the coupled system,future work should be focused on the development of more efficient and stable catalysts,careful design of the electrolytic cells for improving the mass transfer and development of environment-friendly processes for recovering the formed formate and biomass oxidation products. 展开更多
关键词 Electrochemical reduction of CO_(2) Formic acid Oxidative conversion of biomass LIGNOCELLULOSE Coupled system
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Ballistic performance of additive manufacturing 316l stainless steel projectiles based on topology optimization method
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作者 Hao Xue Tao wang +2 位作者 Xinyu Cui yifan wang Guangyan Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期1-17,共17页
Material and structure made by additive manufacturing(AM)have received much attention lately due to their flexibility and ability to customize complex structures.This study first implements multiple objective topology... Material and structure made by additive manufacturing(AM)have received much attention lately due to their flexibility and ability to customize complex structures.This study first implements multiple objective topology optimization simulations based on a projectile perforation model,and a new topologic projectile is obtained.Then two types of 316L stainless steel projectiles(the solid and the topology)are printed in a selective laser melt(SLM)machine to evaluate the penetration performance of the projectiles by the ballistic test.The experiment results show that the dimensionless specific kinetic energy value of topologic projectiles is higher than that of solid projectiles,indicating the better penetration ability of the topologic projectiles.Finally,microscopic studies(scanning electron microscope and X-ray micro-CT)are performed on the remaining projectiles to investigate the failure mechanism of the internal structure of the topologic projectiles.An explicit dynamics simulation was also performed,and the failure locations of the residual topologic projectiles were in good agreement with the experimental results,which can better guide the design of new projectiles combining AM and topology optimization in the future. 展开更多
关键词 Additive manufacturing Topology optimization Ballistic performance Projectile design
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An End-To-End Hyperbolic Deep Graph Convolutional Neural Network Framework
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作者 Yuchen Zhou Hongtao Huo +5 位作者 Zhiwen Hou Lingbin Bu yifan wang Jingyi Mao Xiaojun Lv Fanliang Bu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期537-563,共27页
Graph Convolutional Neural Networks(GCNs)have been widely used in various fields due to their powerful capabilities in processing graph-structured data.However,GCNs encounter significant challenges when applied to sca... Graph Convolutional Neural Networks(GCNs)have been widely used in various fields due to their powerful capabilities in processing graph-structured data.However,GCNs encounter significant challenges when applied to scale-free graphs with power-law distributions,resulting in substantial distortions.Moreover,most of the existing GCN models are shallow structures,which restricts their ability to capture dependencies among distant nodes and more refined high-order node features in scale-free graphs with hierarchical structures.To more broadly and precisely apply GCNs to real-world graphs exhibiting scale-free or hierarchical structures and utilize multi-level aggregation of GCNs for capturing high-level information in local representations,we propose the Hyperbolic Deep Graph Convolutional Neural Network(HDGCNN),an end-to-end deep graph representation learning framework that can map scale-free graphs from Euclidean space to hyperbolic space.In HDGCNN,we define the fundamental operations of deep graph convolutional neural networks in hyperbolic space.Additionally,we introduce a hyperbolic feature transformation method based on identity mapping and a dense connection scheme based on a novel non-local message passing framework.In addition,we present a neighborhood aggregation method that combines initial structural featureswith hyperbolic attention coefficients.Through the above methods,HDGCNN effectively leverages both the structural features and node features of graph data,enabling enhanced exploration of non-local structural features and more refined node features in scale-free or hierarchical graphs.Experimental results demonstrate that HDGCNN achieves remarkable performance improvements over state-ofthe-art GCNs in node classification and link prediction tasks,even when utilizing low-dimensional embedding representations.Furthermore,when compared to shallow hyperbolic graph convolutional neural network models,HDGCNN exhibits notable advantages and performance enhancements. 展开更多
关键词 Graph neural networks hyperbolic graph convolutional neural networks deep graph convolutional neural networks message passing framework
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Oral administration of Bacillus coagulans TQ-35 alleviates allergic responses in OVA-sensitive BALB/c mice
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作者 yifan wang Shanjun Chen +4 位作者 Chong wang Yi Zhang Hongliang Zeng Linglin Fu Yanbo wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1246-1257,共12页
Bacillus coagulans has been extensively studied so far,but there has been a lack of research on its usage in allergy.In this study,we designed to assess the effect of different concentrations of B.coagulans on food al... Bacillus coagulans has been extensively studied so far,but there has been a lack of research on its usage in allergy.In this study,we designed to assess the effect of different concentrations of B.coagulans on food allergy in a BALB/c mouse model of ovalbumin(OVA)-induced food allergy and its effect on gut microbes.The assessment of symptoms,specific immunoglobulin E(IgE),T-cell differentiation,and related gene expression levels in sensitized mice by assay indicated that high doses of oral B.coagulans could alleviate allergic symptoms.Treatment with B.coagulans,in the high-dose group,significantly reduced IgE and IgG1 levels and modulated the balance of T helper type 1 cell(Th1)and Th2 and the expression of relevant genes in the spleen.16S rRNA analysis showed that probiotics improved the structure of the microbiota,in particular by boosting the percentage of Clostridia,Bacteroides vulgatus and Enterococcus faecium,and by increasing the abundance of microbial species,thereby modulating the immune system.Therefore,this study can provide insights into the practical application of B.coagulans doses to alleviate OVA allergy. 展开更多
关键词 Bacillus coagulans TQ-35 Food allergy Ovalbumin(OVA) Gut microbiota
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Comparison of fungal vs bacterial infections in the medical intensive liver unit:Cause or corollary for high mortality?
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作者 Sarah Khan Hanna Hong +6 位作者 Stephanie Bass yifan wang Xiao-Feng wang Omar T Sims Christine E Koval Aanchal Kapoor Christina C Lindenmeyer 《World Journal of Hepatology》 2024年第3期379-392,共14页
BACKGROUND Due to development of an immune-dysregulated phenotype,advanced liver disease in all forms predisposes patients to sepsis acquisition,including by opportunistic pathogens such as fungi.Little data exists on... BACKGROUND Due to development of an immune-dysregulated phenotype,advanced liver disease in all forms predisposes patients to sepsis acquisition,including by opportunistic pathogens such as fungi.Little data exists on fungal infection within a medical intensive liver unit(MILU),particularly in relation to acute on chronic liver failure.AIM To investigate the impact of fungal infections among critically ill patients with advanced liver disease,and compare outcomes to those of patients with bacterial infections.METHODS From our prospective registry of MILU patients from 2018-2022,we included 27 patients with culture-positive fungal infections and 183 with bacterial infections.We compared outcomes between patients admitted to the MILU with fungal infections to bacterial counterparts.Data was extracted through chart review.RESULTS All fungal infections were due to Candida species,and were most frequently blood isolates.Mortality among patients with fungal infections was significantly worse relative to the bacterial cohort(93%vs 52%,P<0.001).The majority of the fungal cohort developed grade 2 or 3 acute on chronic liver failure(ACLF)(90%vs 64%,P=0.02).Patients in the fungal cohort had increased use of vasopressors(96%vs 70%,P=0.04),mechanical ventilation(96%vs 65%,P<0.001),and dialysis due to acute kidney injury(78%vs 52%,P=0.014).On MILU admission,the fungal cohort had significantly higher Acute Physiology and Chronic Health Evaluation(108 vs 91,P=0.003),Acute Physiology Score(86 vs 65,P=0.003),and Model for End-Stage Liver Disease-Sodium scores(86 vs 65,P=0.041).There was no significant difference in the rate of central line use preceding culture(52%vs 40%,P=0.2).Patients with fungal infection had higher rate of transplant hold placement,and lower rates of transplant;however,differences did not achieve statistical significance.CONCLUSION Mortality was worse among patients with fungal infections,likely attributable to severe ACLF development.Prospective studies examining empiric antifungals in severe ACLF and associations between fungal infections and transplant outcomes are critical. 展开更多
关键词 FUNGAL INFECTION SEPSIS Acute on chronic liver failure Intensive care
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The Solar Upper Transition Region Imager(SUTRI)Onboard the SATech-01 Satellite 被引量:3
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作者 Xianyong Bai Hui Tian +56 位作者 Yuanyong Deng Zhanshan wang Jianfeng Yang Xiaofeng Zhang Yonghe Zhang Runze Qi Nange wang Yang Gao Jun Yu Chunling He Zhengxiang Shen Lun Shen Song Guo Zhenyong Hou Kaifan Ji Xingzi Bi Wei Duan Xiao Yang Jiaben Lin Ziyao Hu Qian Song Zihao Yang Yajie Chen Weidong Qiao Wei Ge Fu Li Lei Jin Jiawei He Xiaobo Chen Xiaocheng Zhu Junwang He Qi Shi Liu Liu Jinsong Li Dongxiao Xu Rui Liu Taijie Li Zhenggong Feng Yamin wang Chengcheng Fan Shuo Liu Sifan Guo Zheng Sun Yuchuan Wu Haiyu Li Qi Yang Yuyang Ye Weichen Gu Jiali Wu Zhe Zhang Yue Yu Zeyi Ye Pengfeng Sheng yifan wang Wenbin Li Qiushi Huang Zhong Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期153-171,共19页
The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the... The Solar Upper Transition Region Imager(SUTRI)onboard the Space Advanced Technology demonstration satellite(SATech-01),which was launched to a Sun-synchronous orbit at a height of~500 km in 2022 July,aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of~3 nm.SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm.The on-orbit observations show that SUTRI images have a field of view of~416×416 and a moderate spatial resolution of~8″without an image stabilization system.The normal cadence of SUTRI images is 30 s and the solar observation time is about16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period.Approximately15 GB data is acquired each day and made available online after processing.SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of~0.5 MK in the solar atmosphere,which has rarely been sampled by existing solar imagers.SUTRI observations will establish connections between structures in the lower solar atmosphere and corona,and advance our understanding of various types of solar activity such as flares,filament eruptions,coronal jets and coronal mass ejections. 展开更多
关键词 Sun:transition region Sun:UV radiation Sun:activity space vehicles:instruments
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基于双跃迁方法的温度鲁棒金刚石磁测量方法
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作者 谢才津 朱云彬 +4 位作者 谢一进 李廷伟 张闻哲 王毅凡 荣星 《中国科学技术大学学报》 CAS CSCD 北大核心 2023年第7期1-7,69,共8页
作为一种具有良好发展前景的室温固态传感器,基于氮-空位(NV)色心的金刚石磁力计在近年来得到了巨大的发展,大量工作展示了其在实现高空间分辨率和高灵敏度方面的潜力。尽管如此,考虑到在大多数应用场景中通常难以避免温度漂移的影响,N... 作为一种具有良好发展前景的室温固态传感器,基于氮-空位(NV)色心的金刚石磁力计在近年来得到了巨大的发展,大量工作展示了其在实现高空间分辨率和高灵敏度方面的潜力。尽管如此,考虑到在大多数应用场景中通常难以避免温度漂移的影响,NV色心零场分裂D对温度的依赖性使得金刚石磁测量方法在实际应用中面临巨大的挑战。在本文中,我们展示了一种基于双跃迁方法的温度鲁棒金刚石磁测量方法,通过在|m_(s)=±1>态未完全退简并的情况下,同时利用|m_(s)=0>次能级和|m_(s)=±1>次能级间的跃迁测量磁场,可以使由温度漂移导致D变化所产生的影响被抵消掉。目前,该方法已经可以使磁测量结果的漂移降低为原来的1/7,通过后续的改进,这种温度鲁棒的金刚石磁测量方法有望在未来被应用于生物磁学和空间科学研究中。 展开更多
关键词 金刚石磁力计 氮-空位色心 温度鲁棒性
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Effect of ultrasonic modification on the protective activity of Flammulina velutipes polysaccharide to prevent ethanol-induced injury on GES-1 cells
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作者 Jinrong Xiao Xin Chen +5 位作者 Jingsi Zhang yifan wang Lei Zhong Qiping Zhan Qiuhui Hu Liyan Zhao 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2451-2459,共9页
Flammulina velutipes(F.velutipes)polysaccharides were modified by ultrasound at the rated power of 150 W and 900 W.The monosaccharide composition,ultraviolet-visible,and Fourier transform infrared spectral characteris... Flammulina velutipes(F.velutipes)polysaccharides were modified by ultrasound at the rated power of 150 W and 900 W.The monosaccharide composition,ultraviolet-visible,and Fourier transform infrared spectral characteristics of F.velutipes polysaccharides(FVP)and their ultrasonic modification products(U-FVPs)were determined.The protective effects of FVP and U-FVPs on human gastric mucosal cells GES-1 were confi rmed for the first time.The mole ratios of glucose and galactose were decreased and the mole ratio of mannose was increased after ultrasonic modification.Compared with the original FVP and the FVP modifi ed by ultrasound of 150 W(U-FVP1),the FVP modifi ed by ultrasound of 900 W(U-FVP2)could better prevent ethanol-induced damage to GES-1 cells.With increasing ultrasound intensity,the protective effect of FVPs on GES-1 cells was significantly enhanced by more effective prevention of intracellular reactive oxygen species(ROS)production and more promotion of expression of triglyceride factor 2(TFF2),prostaglandin E2(PGE2),epidermal growth factor(EGF),and transforming growth factorβ1(TGF-β1)mRNA.The ultrasonic modifi cation might be an effective way to develop novel F.velutipes polysaccharides that could effectively resist the gastric injury caused by excessive alcohol consumption. 展开更多
关键词 Flammulina velutipes polysaccharide Ultrasonic modification GES-1 cell Gastric ulcer Ethanol-induced injury
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Single-flux-quantum-based qubit control with tunable driving strength
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作者 刘匡 王一凡 +3 位作者 季波 高万鹏 林志荣 王镇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期623-627,共5页
Single-flux-quantum(SFQ)circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors.SFQ-based quantum gates have been designed and realized.Howeve... Single-flux-quantum(SFQ)circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors.SFQ-based quantum gates have been designed and realized.However,current control schemes are difficult to tune the driving strength to qubits,which restricts the gate length and usually induces leakage to unwanted levels.In this study,we design the scheme and corresponding pulse generator circuit to continuously adjust the driving strength by coupling SFQ pulses with variable intervals.This scheme not only provides a way to adjust the SFQ-based gate length,but also proposes the possibility to tune the driving strength envelope.Simulations show that our scheme can suppress leakage to unwanted levels and reduce the error of SFQ-based Clifford gates by more than an order of magnitude. 展开更多
关键词 superconducting qubit qubit control single-flux-quantum(SFQ)circuit
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Design,Fabrication and Assembly of the Solar Upper Transition Region Imager(SUTRI)
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作者 Zhanshan wang Jun Yu +31 位作者 Runze Qi Chunling He Zhengxiang Shen Li Jiang Weichen Gu Jiali Wu Zhe Zhang Pengfeng Sheng yifan wang Yue Yu Zeyi Ye JingJing Xia Yujie Xing Hongfei Jiao Bin Ma Qiushi Huang Zhong Zhang Xianyong Bai Yuanyong Deng Hui Tian Nange wang Lun Shen Song Guo Lei Jing Xiaobo Chen Yang Gao Xiaocheng Zhu Xiaofeng Zhang Junwang He Qi Shi Shuo Liu Xingzi Bi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第9期91-104,共14页
The Solar Upper Transition Region Imager(SUTRI)focuses on the solar transition region to achieve dynamic imaging observation of the upper transition region.In this paper,we report the optical system design,mechanical ... The Solar Upper Transition Region Imager(SUTRI)focuses on the solar transition region to achieve dynamic imaging observation of the upper transition region.In this paper,we report the optical system design,mechanical design,ultrasmooth mirror manufacture and measurement,EUV multilayer film coating,prelaunch installation and calibration for the SUTRI payload at IPOE,Tongji University.Finally,the SUTRI carried by the SATech-01 satellite was successfully set to launch.All functions of this telescope were normal,and the observation results obtained in orbit were consistent with the design. 展开更多
关键词 Astronomical Instrumentation-Methods and Techniques-Sun transition region-techniques high angular resolution
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Involvement of 2'-5'oligoadenylate synthetase-like proteinin the survivalof Mycobacterium tuberculosis avirulent strain in macrophages
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作者 Aikebaier Reheman Xiaojian Cao +8 位作者 yifan wang Xi Nie Gang Cao Wei Zhou Bing Yang Yingying Lei Weipan Zhang Muhammad Ahsan Naeem Xi Chen 《Animal Diseases》 CAS 2023年第4期275-285,共11页
Mycobacterium tuberculosis(M.tuberculosis)can replicate in the macrophage by interfering with many host protein functions.While it is far from known these host proteins for controlling M.tuberculosis infection.Herein,... Mycobacterium tuberculosis(M.tuberculosis)can replicate in the macrophage by interfering with many host protein functions.While it is far from known these host proteins for controlling M.tuberculosis infection.Herein,we infected macrophages including THP-1 and Raw264.7 cells with M.tuberculosis and identified the differentially expressed genes(DEGs)in the interferon signaling pathway.Among them,2'-5'oligoadenylate synthetase-like(OASL)underwent the greatest upregulation in M.tuberculosis-infected macrophages.Knockdown of the expression of OASL attenuated M.tuberculosis survival in macrophages.Further,bioinformatics analysis revealed the potential interaction axis of OASL-TAB3-RvO127,which was further validated by the yeast-two-hybrid(Y2H)assay and Co-IP.This interaction axis might regulate the M.tuberculosis survival and proliferation in macrophages.The study reveals a possible role of OASL during M.tuberculosis infection as a target to control its propagation. 展开更多
关键词 Mycobacterium tuberculosis INTERFERON Interferon stimulated genes OASL
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Association of maternal hypertensive disorders in pregnancy with infant neurodevelopment
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作者 Bo Huang yifan wang +7 位作者 Yangqian Jiang Hong Lv Tao Jiang Yun Qiu Qun Lu Jiangbo Du Yuan Lin Hongxia Ma 《The Journal of Biomedical Research》 CAS CSCD 2023年第6期479-491,共13页
Inconsistent findings have been reported regarding the associations between hypertensive disorders in pregnancy (HDP) and infant neurodevelopment. Leveraging data from the Jiangsu Birth Cohort, in the present study, w... Inconsistent findings have been reported regarding the associations between hypertensive disorders in pregnancy (HDP) and infant neurodevelopment. Leveraging data from the Jiangsu Birth Cohort, in the present study, we re-visited such associations in one-year-old infants from 2 576 singleton pregnancies and 261 twin pregnancies. We first assessed infant neurodevelopment by the Bayley Scales of Infant and Toddler Development Screening Test (the Third Edition), and then estimated its association with maternal HDP using general linear regression models and Poisson regression models. In singleton pregnancies, compared with mothers unexposed to HDP, infants born to mothers with chronic hypertension exhibited a lower score (β, −0.67;95% confidence interval [CI], −1.19-−0.15) and a higher risk of "non-optimal" gross motor development (risk ratio [RR], 2.21;95% CI, 1.02-4.79);in twin pregnancies, infants born to mothers with HDP exhibited lower scores in cognition (β, −0.49;95% CI, −0.96-−0.01), receptive communication (β, −0.55;95% CI, −1.03-−0.06), and gross motor (β, −0.44;95% CI, −0.86-−0.03), and at a higher risk of "non-optimal" gross motor development (RR, 2.12;95% CI, 1.16-3.88). These findings indicate that infants born to mothers with HDP may have inferior neurodevelopment outcomes at the age of one year. 展开更多
关键词 hypertensive disorders in pregnancy infant neurodevelopment prospective birth cohort study
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流媒体电视平台海外拓展中的资本—领土逻辑考察——以Netflix巴西个案为进路
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作者 周娟 王一帆 《新媒体与社会》 2023年第3期375-385,401,402,共13页
流媒体电视平台纷纷开启海外拓展之路。作为资本表征的流媒体电视在进行非领土化服务和内容的海外传播时,往往会受到目标国家和地区政治、经济、文化、宗教等多方面意识形态差异所带来的挑战。本文以Netflix巴西原创剧集《黑金高墙》、... 流媒体电视平台纷纷开启海外拓展之路。作为资本表征的流媒体电视在进行非领土化服务和内容的海外传播时,往往会受到目标国家和地区政治、经济、文化、宗教等多方面意识形态差异所带来的挑战。本文以Netflix巴西原创剧集《黑金高墙》、《基督的第一个诱惑》和《看不见的城市》为案例,剖析全球化背景下流媒体电视在非领土扩张的过程中面临的地域性问题,观察数字时代全球化的流媒体电视与民族国家之间动态的博弈关系,思考中国流媒体电视海外传播创新可行的思路。 展开更多
关键词 流媒体电视 Netflix 资本逻辑 领土逻辑
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全方位多层次立体化的应用化学专业实验教学模式的构建与实践 被引量:5
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作者 黄健涵 陈立妙 +9 位作者 曾冬铭 李亚娟 桑商斌 潘春跃 王海燕 唐俊涛 宋相志 王一凡 罗一鸣 刘又年 《大学化学》 CAS 2021年第11期114-119,共6页
在新工科和国家一流本科专业建设大背景下,针对当前应用化学专业学生实验教学中能力和综合素质培养存在的问题,结合中南大学应用化学专业的自身特色与优势,创新教育理念,按照目标导向的方式对实验教学体系、教学内容和教学方法等方面进... 在新工科和国家一流本科专业建设大背景下,针对当前应用化学专业学生实验教学中能力和综合素质培养存在的问题,结合中南大学应用化学专业的自身特色与优势,创新教育理念,按照目标导向的方式对实验教学体系、教学内容和教学方法等方面进行系统性的教学改革与实践,建立了全方位多层次立体化的应用化学专业实验教学新模式,取得了良好的教学效果。 展开更多
关键词 应用化学 实验教学 教学模式 多层次 立体化
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Ag(111)表面Ag配位结构的分等级组装 被引量:1
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作者 李若宁 张雪 +8 位作者 薛娜 李杰 吴天昊 徐榛 王一帆 李娜 唐浩 侯士敏 王永锋 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第8期22-27,共6页
表面辅助的金属有机纳米结构因其结构稳定性和潜在应用受到广泛关注。在金属有机纳米结构中,金属原子来源于外部沉积的金属或金属表面原子。外部沉积的金属原子种类多样,取决于目标纳米结构。然而,金属表面原子受限于表面科学常用的金... 表面辅助的金属有机纳米结构因其结构稳定性和潜在应用受到广泛关注。在金属有机纳米结构中,金属原子来源于外部沉积的金属或金属表面原子。外部沉积的金属原子种类多样,取决于目标纳米结构。然而,金属表面原子受限于表面科学常用的金、银和铜单晶金属表面。金属有机纳米结构大多包括Au配位或是Cu配位结构,而只有少量的用表面Ag原子构成。分子金属相互作用的进一步研究有助于预期纳米结构的精确控制形成。至于构建基元,有机分子通过M―C、M―N和M―O键与表面金属原子配位。末端炔反应或者乌尔曼耦合能够实现C―M―C节点的形成。Cu和Au原子能够与含有末端氰基或吡啶基官能团的分子配位形成N―M―N键。另外,表面Ag增原子能够通过Ag―N配位键与酞菁分子配位。然而,M―O配位键的相关研究较少。因此,我们计划使用末端羟基分子与Ag增原子配位形成金属有机配位纳米结构去研究O―Ag节点。我们通过扫描隧道显微镜利用4,4’-二羟基-1,1’:3’,1’’-三联苯分子(4,4’-dihydroxy-1,1’:3’,1’’-terphenyl,H3PH)和Ag增原子成功构筑了一系列二维有序纳米结构。在室温下,蒸镀的H3PH分子自组装形成由环氢键连接的密堆积结构。当退火温度提升到330K,一种新的纳米结构出现了,该结构由O―Ag配位键和氢键共同作用形成。进一步地提升退火温度至420K,蜂巢结构和共存的二重配位链出现,这两种结构中仅由O―Ag―O键构成。为分析金属分子反应路径和O―Ag―O键的能量势垒,我们对该体系进行密度泛函理论计算。计算结果显示,O―Ag键形成的能量势垒是1.41 eV,小于O―Ag―O节点1.85 e V的能量势垒。这也解释了分等级金属-有机纳米结构形成的原因。我们的实验结果提供了一种利用有机小分子和金属增原子来设计和构筑分等级二维纳米结构的有效方法。 展开更多
关键词 退火 环氢键 配位 扫描隧道显微镜 密度泛函理论
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Epithelial-mesenchymal transition in breast cancer progression and metastasis 被引量:33
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作者 yifan wang Binhua P. Zhou 《Chinese Journal of Cancer》 SCIE CAS CSCD 北大核心 2011年第9期603-611,共9页
Breast cancer is the most common cancer in women,and approximately 90% of breast cancer deaths are caused by local invasion and distant metastasis of tumor cells.Epithelial-mesenchymal transition(EMT) is a vital proce... Breast cancer is the most common cancer in women,and approximately 90% of breast cancer deaths are caused by local invasion and distant metastasis of tumor cells.Epithelial-mesenchymal transition(EMT) is a vital process for large-scale cell movement during morphogenesis at the time of embryonic development.Tumor cells usurp this developmental program to execute the multi-step process of tumorigenesis and metastasis.Several transcription factors and signals are involved in these events.In this review,we summarize recent advances in breast cancer researches that have provided new insights in the molecular mechanisms underlying EMT regulation during breast cancer progression and metastasis.We especially focus on the molecular pathways that control EMT. 展开更多
关键词 乳腺癌 上皮 间质 肿瘤细胞 分子机制 EMT 胚胎发育 细胞运动
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Quality control of Semen Ziziphi Spinosae standard decoction based on determination of multi-components using TOF-MS/MS and UPLC-PDA technology 被引量:6
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作者 Di wang Qing Li +5 位作者 Ran Liu Huarong Xu Yidi Yin yifan wang Huijia wang Kaishun Bi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第6期406-413,共8页
A sensitive,fast and comprehensive method for the quality assessment of Semen Ziziphi Spinosae(SZS)standard decoction with characterization of its chemical components was developed and validated.UPLC-Q/TOF-MS/MS syste... A sensitive,fast and comprehensive method for the quality assessment of Semen Ziziphi Spinosae(SZS)standard decoction with characterization of its chemical components was developed and validated.UPLC-Q/TOF-MS/MS system was used to identify thirty-six chemical components of SZS standard decoction which included nucleosides,phenolic acids,alkaloids,and flavonoids.Furthermore,a UPLC-PDA method was validated to simultaneously determine adenosine,protocatechuic acid,magnoflorine,catechin,protocatechin,vicenin II,spinosin,kaempferol-3-rutinoside,and 6'''-feruloylspinosin which represent four species of characteristic compounds.The qualitative method had been validated according to Chinese Pharmacopoeia(2015 edition)in terms of lineary,repeatability,recovery and stability for all analytes,with the results showing good precision,accuracy and stability.In conclusion,the method using UPLC combined with MS and PDA provided a novel way for the standardization and identification of SZS standard decoction,and also offered a basis for qualitative analysis and quality assessment of the preparations for SZS standard decoction. 展开更多
关键词 IDENTIFICATION Semen Ziziphi Spinosae(SZS) Standard decoction Quality assessment UPLC TOF-MS/MS
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Variation in hydraulic conductivity of fractured rocks at a dam foundation during operation 被引量:5
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作者 Yi-Feng Chen Jun Zeng +4 位作者 Hongtao Shi yifan wang Ran Hu Zhibing Yang Chuang-Bing Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第2期351-367,共17页
Characterizing the permeability variation in fractured rocks is important in various subsurface applications,but how the permeability evolves in the foundation rocks of high dams during operation remains poorly unders... Characterizing the permeability variation in fractured rocks is important in various subsurface applications,but how the permeability evolves in the foundation rocks of high dams during operation remains poorly understood.This permeability change is commonly evidenced by a continuous decrease in the amount of discharge(especially for dams on sediment-laden rivers),and can be attributed to fracture clogging and/or hydromechanical coupling.In this study,the permeability evolution of fractured rocks at a high arch dam foundation during operationwas evaluated by inverse modeling based on the field timeseries data of both pore pressure and discharge.A procedure combining orthogonal design,transient flow modeling,artificial neural network,and genetic algorithm was adopted to efficiently estimate the hydraulic conductivity values in each annual cycle after initial reservoir filling.The inverse results show that the permeability of the dam foundation rocks follows an exponential decay annually during operation(i.e.K/K0=0.97e^(-0.59t)+0.03),with good agreement between field observations and numerical simulations.The significance of the obtained permeability decay function was manifested by an assessment of the long-term seepage control performance and groundwater flow behaviors at the dam site.The proposed formula is also of merit for characterizing the permeability change in riverbed rocks induced by sediment transport and deposition. 展开更多
关键词 Permeability variation Fractured rock Fracture clogging Seepage control Dam engineering
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大豆细胞核雄性不育基因研究进展 被引量:7
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作者 孙小媛 王一帆 +6 位作者 王韫慧 蔺佳雨 李金红 丘远涛 方小龙 孔凡江 李美娜 《遗传》 CAS CSCD 北大核心 2021年第1期52-65,共14页
雄性不育是指植物雄蕊不能正常生长和产生有活力花粉粒的现象。利用雄性不育突变体开展杂交育种工作,是快速提高作物单产的有效途径。目前,通过杂种制种已大幅度提高了水稻(Oryza sativa L.)、玉米(Zea mays L.)和小麦(Triticum aestivu... 雄性不育是指植物雄蕊不能正常生长和产生有活力花粉粒的现象。利用雄性不育突变体开展杂交育种工作,是快速提高作物单产的有效途径。目前,通过杂种制种已大幅度提高了水稻(Oryza sativa L.)、玉米(Zea mays L.)和小麦(Triticum aestivum L.)等作物的产量。大豆(Glycinemax(L.)Merr.)作为自花授粉作物,通过人工去雄生产杂交种子不仅困难而且经济上不可行。由于适用于杂交种生产的不育系资源短缺,目前大豆还没有实现大规模杂种优势利用。因此,快速实现大豆杂种优势利用迫切需要鉴定稳定的大豆雄性不育系统。本文总结了大豆细胞核雄性不育(genic male sterility, GMS)突变体及不育基因研究进展,同时结合拟南芥(Arabidopsis thaliana)、水稻和玉米中已报道的细胞核雄性不育基因,从反向遗传学的角度,为大豆核雄性不育基因的鉴定提供依据。 展开更多
关键词 大豆 细胞核雄性不育 反向遗传学
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