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Construction of 3D aerogels consisting of cellulose and BNNSs bridged by AgNPs for enhancing thermal and tribological properties of polyurethane composites
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作者 yu he yuanya Zhang +2 位作者 Yongjun Zhou Junya yuan Xuehu Men 《Nano Materials Science》 CSCD 2024年第6期752-763,共12页
Waterborne polyurethane(WPU)is attracting widespread attention in the friction field,but pure WPU cannot meet the wear resistance requirements due to poor thermal and self-lubricating properties.Herein,a novel cellulo... Waterborne polyurethane(WPU)is attracting widespread attention in the friction field,but pure WPU cannot meet the wear resistance requirements due to poor thermal and self-lubricating properties.Herein,a novel cellulose/BNNSs-AgNPs aerogel(CBAg)composed of zero-dimensional silver nanoparticles(AgNPs),onedimensional cellulose and two-dimensional boron nitride nanosheets(BNNSs)was successfully fabricated.Specifically,AgNPs were loaded onto the surface of BNNSs,which could serve as bridges to connect adjacent BNNSs.Cellulose was used to construct a 3D skeleton structure for stabilizing better dispersion of inorganic fillers.Finally,the thermal and tribological properties of CBAg-WPU were improved compared to pure WPU,with a 69%increase in thermal conductivity and an 89%reduction in wear rate.This was attributed to the load-bearing capacity of cellulose and outstanding thermal and lubricant capability of BNNSs-AgNPs.In addition,BNNSs and AgNPs inside the aerogel were transferred to the sliding interface and participated in the formation of high-quality friction transfer film,further endowing CBAg-WPU composites prominent tribological performance.Therefore,the novel design of 3D hybrid aerogels provided a promising avenue to improve the tribological performance of WPU composites. 展开更多
关键词 BNNSs-AgNPs Hybrid aerogel Polymer-based composites Thermal conduction pathways Tribological properties
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Histological,transcriptomic,and gene functional analyses reveal the regulatory events underlying gibberellin-induced parthenocarpy in tomato 被引量:1
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作者 Shaobo Niu yu he +3 位作者 Siwei Yan Zhengliang Sun Run Cai Yan Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期156-170,共15页
Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic trait.Here,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with s... Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic trait.Here,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with smaller size but unchanged shape in tomato(Solanum lycopersicum).These fruits exhibited a thicker pericarp,undeveloped ovules,and few jelly tissues,leading to smaller locules with empty cavities.Histological investigation showed that GA treatment produced more cell layers with larger cells in the pericarp,suggesting its promotion in both cell division and expansion.Transcriptomic analyses between GA-3and mock-treated unpollinated ovaries/fruits identified a large number of differentially expressed genes related to hormones,cell division,cell expansion,and transcription factors,implying that they coordinately regulated parthenocarpy conferred by GA.In particular,the downregulation of five reported repressors of tomato parthenocarpy,including two auxin signaling components,AUXIN RESPONSE FACTOR5(SlARF5)and Sl ARF7,and three MADS-box genes,TOMATO APETALA3(TAP3),TOMATO PISTILLATA(TPI),and AGAMOUS-LIKE6(SlAGL6),after GA treatment might play a key role in this process.Furthermore,we found that the knockdown of a GA signaling factor SlMYB33,which was depressed by GA treatment,induced parthenocarpic fruit set in tomato,an effect that might have been achieved by enhancing GA biosynthesis and decreasing the expression of some repressors of tomato parthenocarpy.Thus,our results provide a basis for understanding the regulatory mechanism of GA in tomato parthenocarpy. 展开更多
关键词 TOMATO GIBBERELLIN PARTHENOCARPY HISTOLOGY Transcriptome SlMYB33
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Exploring the topographical pattern beneath the water surface: Global bathymetric volume-area-height curves(BVAH) of inland surface water bodies
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作者 Siyu Zhu Wei Wan +15 位作者 Guoqing Zhang Zhaoyuan Yao yue Xu Baojian Liu Zhizhou Guo Zengliang Luo Wentao Xiong Rui Ji Qingwen Ji yu he Feng Lv Weizhen Fang Xiao Tan Qian Huang Lei Xiao Huan Li 《Geodesy and Geodynamics》 EI CSCD 2024年第6期602-615,共14页
Global inland surface water bodies such as lakes and reservoirs,important components of the hydrosphere and ecosphere,are increasingly affected by climate change.Generating bathymetric volume-areaheight (BVAH) curves ... Global inland surface water bodies such as lakes and reservoirs,important components of the hydrosphere and ecosphere,are increasingly affected by climate change.Generating bathymetric volume-areaheight (BVAH) curves for global inland surface water bodies can enhance our understanding of their topography and climate impacts.However,accurately quantifying the topographic patterns of these water bodies remains challenging due to the difficulties in collecting comprehensive bathymetric data.Therefore,we collected and processed over 2000 bathymetric maps of global water bodies from over 50 different data sources and then developed the BVAH model.Finally,the BVAH hydrological curves of 16671 global inland surface water bodies (larger than 10 km~2) were generated.The results include but are not limited to (1) For most targeted water bodies,area (A) and volume (V) exhibit significant power function relationships with surface heights (H),with optimal power values quantified as 1.42 for A and 2.42 for V.(2) The BVAH model outperforms GLOBathy in estimating area and volume changes,achieving higher correlation coefficients (CC) of approximately 0.962 for the area and 0.991 for volume,and demonstrating lower percentages of root mean squared errors (PRMSE) around 10.9% for the area and 4.8% for volume.(3) In the case study of the Xizang Plateau and various large global reservoirs,the BVAH curve database can capture dynamic volume changes.As a unified simulation of the bathymetric topographical patterns,our bathymetric dataset and corresponding BVAH curve database have great potential to contribute to effective water resource management and ecological conservation efforts worldwide. 展开更多
关键词 Global inland water bodies Hydrological curves Bathymetric map Climate change
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Racemic dielectric metasurfaces for arbitrary terahertz polarization rotation and wavefront manipulation
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作者 Jie Li Xueguang Lu +14 位作者 Hui Li Chunyu Song Qi Tan yu he Jingyu Liu Li Luo Tingting Tang Tingting Liu Hang Xu Shuyuan Xiao Wanxia Huang yun Shen Yan Zhang Yating Zhang Jianquan Yao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第10期41-50,共10页
Dielectric chiral metasurface is a new type of planar and efficient chiral optical device that shows strong circular dichroism or optical activity,which has important application potential in optical sensing and displ... Dielectric chiral metasurface is a new type of planar and efficient chiral optical device that shows strong circular dichroism or optical activity,which has important application potential in optical sensing and display.However,the two types of chiral optical responses in conventional chiral metasurfaces are often interdependent,as their modulation of the amplitudes and phases of orthogonal circularly polarized components is correlated,which limits the further progress of chiral meta-devices.Here we propose a new scheme for independently designing the circular dichroism and optical activity of chiral metasurfaces to further control the polarization and wavefront of transmitted waves.Inspired by mixtures of chiral molecular isomers,we use the dielectric isomer resonators to form“super-units”instead of single meta-atoms for chiral responses in terahertz band,which is called racemic metasurface.By introducing two levels of Pancharatnam-Berry phases between meta-atoms and“super-units”,the polarization rotation angle and wavefront of the beam can be designed without the far-field circular dichroism.We demonstrate the strong control ability on terahertz waves of this scheme through simulation and experiments.In addition,this new type of device with near-field chirality but no far-field circular dichroism may also have important value in optical sensing and other technologies. 展开更多
关键词 RACEMIC dielectric metasurfaces terahertz waves CHIRALITY
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Micropulse transscleral laser therapy for secondary angle-closure glaucoma in nanophthalmos: a case report
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作者 Ping yu Bai-yu Hu +4 位作者 yu he Lin Jing Han-Ying Fan Jing Shu Liu-Zhi Zeng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1381-1384,共4页
Dear Editor,The choice of surgical intervention for nanophthalmos patients with secondary angle-closure glaucoma poses a challenging decision for ophthalmologists.Because nanophthalmos patients who have undergone filt... Dear Editor,The choice of surgical intervention for nanophthalmos patients with secondary angle-closure glaucoma poses a challenging decision for ophthalmologists.Because nanophthalmos patients who have undergone filtration surgery or other intraocular procedures are more susceptible to severe complications,including choroidal effusion,malignant glaucoma,and explosive choroidal hemorrhage,all of which can lead to vision loss[1].This dilemma is particularly pronounced in patients with shorter axial lengths.Micropulse transscleral laser therapy(M-TLT),also known as micropulse transscleral cyclophotocoagulation(MP-TSCPC),is a nonincisional laser therapy surgery for glaucoma[2].In 2015,Golan and Kurtz[3]were the first to report four patients with secondary angle-closure glaucoma in nanophthalmos with axial lengths ranging between 17 and 19 mm(mean 18 mm)who were successfully treated with M-TLT,and choroidal detachment was observed in all patients(recovery spontaneously in two patients and recovery after systemic steroid treatment in the other two),of which two had a slight decrease in visual acuity. 展开更多
关键词 GLAUCOMA SURGERY CLOSURE
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叶天士和吴鞠通刚柔用药经验探骊
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作者 张文静 王雨菡 +4 位作者 单燕然 张月敏 汪伯川 王振东 于河 《江苏中医药》 2025年第2期61-64,共4页
刚柔药性分类是对中药药性的高度概括,叶天士、吴鞠通对于刚柔用药认识深刻,其著作中关于药性之刚柔记载较多,医案完整,内容丰富。刚药气味俱雄,效专力宏,多用于温阳和祛湿,包括醒脾苏阳、畅通胃腑、回阳救逆、宣湿化浊等,但易伤阴耗气... 刚柔药性分类是对中药药性的高度概括,叶天士、吴鞠通对于刚柔用药认识深刻,其著作中关于药性之刚柔记载较多,医案完整,内容丰富。刚药气味俱雄,效专力宏,多用于温阳和祛湿,包括醒脾苏阳、畅通胃腑、回阳救逆、宣湿化浊等,但易伤阴耗气,温病无湿、体质不适、久病入络等患者应当慎用。柔药性质柔润,功效和缓,多用于凉柔滋阴或温柔通补,但易滋腻碍胃,组方应当轻灵,湿重之人、脾胃虚弱患者应当慎用柔药。刚柔配伍使用可以补偏救弊,祛邪而不伤阴,柔养而不滋腻。刚柔药性分类和使用经验,体现了中医阴阳平衡与统一的思想,是温病学家对于性味合化、制方用药思路的创新与实践,是对君臣佐使和功效主治组方思路的重要补充。 展开更多
关键词 药性 刚药 柔药 叶天士 吴鞠通 中药
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Involvement of microRNA-181a and Bim in a rat model of retinal ischemia-reperfusion injury 被引量:4
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作者 yu he Jin-Nan Liu +1 位作者 Jun-Jun Zhang Wei Fan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第1期33-40,共8页
AIM:To investigate the changes in the expression of micro RNA-181a(mi R-181a)and Bim in a rat model of retinal ischemia-reperfusion(RIR),to explore their target relationship in RIR and their involvement in regula... AIM:To investigate the changes in the expression of micro RNA-181a(mi R-181a)and Bim in a rat model of retinal ischemia-reperfusion(RIR),to explore their target relationship in RIR and their involvement in regulating apoptosis of retinal ganglion cells(RGCs).·M ETHODS:Target gene prediction for mi R-181a was performed with the aid of bioinformatics and Bim was identified as a potential target gene of mi R-181a.A rat model of RIR was created by increasing the intraocular pressure.RGCs in the flatmounted retinas were labeled with Brn3,a marker for alive RGCs,by immunofluorescent staining.The changes in the number of RGCs after RIR were recorded.Quantitative reverse transcription-polymerase chain reaction(q RT-PCR)was used to determine the expression level of mi R-181a in the retina.Bim/Brn3 double immunofluorescence was used to detect the localization of Bim.The expression of Bim in the retina was determined with the aids of Western blot and q RT-PCR.·R ESULTS:Compared with the negative control group,the density of RGCs was significantly lower in the ischemia/reperfusion(I/R)-24h and I/R-72h groups(〈0.001).The expression level of mi R-181a started to decrease at 0h after RIR,and further decreased at 24h and 72h compared with the negative control group(〈0.001).Bim was significantly upregulated at 12h after RIR(〈0.05)and reached peak at 24,72h compared with the negative control group(〈0.01).Pearson correlation analysis showed that the expression level of Bim was negatively correlated with the expression level of mi R-181a and the density of RGCs.·CONCLUSION:Bim may be a potential target gene of mi R-181a.Both mi R-181a and Bim are involved in RGCs death in RIR.RIR may promote RGCs apoptosis in the retina downregulation of mi R-181a and its inhibition on Bim expression. 展开更多
关键词 microRNA-181a BIM retinal ischemiareperfusion target gene retinal ganglion cells APOPTOSIS
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Comparison of the postoperative pain change and spinal stenosis rate between percutaneous vertebroplasty combined with radiofrequency ablation and with ^(125)I particle implantation in the treatment of metastatic spinal cord compression:A retrospective st 被引量:7
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作者 yu he Shilong Han +2 位作者 Chungen Wu Fei Ge Jianbo Wang 《Journal of Interventional Medicine》 2021年第4期197-202,共6页
Background context:Metastatic spinal cord compression(MSCC)seriously affects the survival rate.Objective:The therapeutic effects of two treatment strategies for MSCC:percutaneous vertebroplasty(PVP)combined with radio... Background context:Metastatic spinal cord compression(MSCC)seriously affects the survival rate.Objective:The therapeutic effects of two treatment strategies for MSCC:percutaneous vertebroplasty(PVP)combined with radiofrequency ablation(RFA)and PVP combined with^(125)I particle implantation,were compared.Study design:Retrospective study.Patient sample:40 patients with MSCC were divided into two groups:19 cases in the RFA group and 21 cases in the^(125)I group.Method:All patients were accessed to determine the differences in pain,which was evaluated using the visual analog scale(VAS)at 1 week,1 month,and 3 months after the operation,and spinal stenosis rates(SSRs),which were measured at 1 and 3 months after the operation,between the two groups.Results:The VAS scores and SSRs at baseline were comparable between the RFA group and the^(125)I group(7.19±2.07 vs 7.42±1.95,37.7%±11.2%vs 41.1%±11.4%).The VAS scores and SSRs at 1 month and 3 months after the operation were significantly reduced in both groups,compared with those at baseline.The VAS scores and SSRs in the^(125)I group were lower than those in the RFA group at 3 months after the operation(1.09±0.97 vs 1.75±1.06 p=0.048 and 12.3%±6.4%vs 18.1%±10.1%p=0.034),while the VAS scores at1 week after the operation in the RFA group were lower than those in the^(125)I group(4.39±1.34 vs 5.05±1.82 p=0.049).Conclusion:PVP combined with RFA has a slight advantage in relieving pain in the short term,while PVP combined with^(125)I particle implantation may have a better effect in the relieving pain and decreasing the SSRs at 3 months after the operation. 展开更多
关键词 Metastatic spinal cord compression Pain management VERTEBROPLASTY Radiofrequency ablation ^(125)I particle
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Comparison of acute pneumonia caused by SARS-CoV-2 and other respiratory viruses in children:a retrospective multi-center cohort study during COVID-19 outbreak 被引量:3
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作者 Guang-Li Ren Xian-Feng Wang +27 位作者 Jun Xu Jun Li Qiong Meng Guo-Qiang Xie Bo Huang Wei-Chun Zhu Jing Lin Cheng-he Tang Sheng Ye Zhuo Li Jie Zhu Zhen Tang Ming-Xin Ma Cong Xie Ying-Wen Wu Chen-Xi Liu Fang Yang yu-Zong Zhou Ying Zheng Shu-Ling Lan Jian-Feng Chen Feng Ye yu he BenQing Wu Long Chen Si-Mao Fu Cheng-Zhong Zheng yuan Shi 《Military Medical Research》 SCIE CSCD 2021年第4期468-480,共13页
Background:Until January 18,2021,coronavirus disease-2019(COVID-19)has infected more than 93 million individuals and has caused a certain degree of panic.Viral pneumonia caused by common viruses such as respiratory sy... Background:Until January 18,2021,coronavirus disease-2019(COVID-19)has infected more than 93 million individuals and has caused a certain degree of panic.Viral pneumonia caused by common viruses such as respiratory syncytial virus,rhinovirus,human metapneumovirus,human bocavirus,and parainfluenza viruses have been more common in children.However,the incidence of COVID-19 in children was significantly lower than that in adults.The purpose of this study was to describe the clinical manifestations,treatment and outcomes of COVID-19 in children compared with those of other sources of viral pneumonia diagnosed during the COVID-19 outbreak.Methods:Children with COVID-19 and viral pneumonia admitted to 20 hospitals were enrolled in this retrospective multi-center cohort study.A total of 64 children with COVID-19 were defined as the COVID-19 cohort,of which 40 children who developed pneumonia were defined as the COVID-19 pneumonia cohort.Another 284 children with pneumonia caused by other viruses were defined as the viral pneumonia cohort.The epidemiologic,clinical,and laboratory findings were compared by Kolmogorov-Smirnov test,t-test,Mann-Whitney U test and Contingency table method.Drug usage,immunotherapy,blood transfusion,and need for oxygen support were collected as the treatment indexes.Mortality,intensive care needs and symptomatic duration were collected as the outcome indicators.Results:Compared with the viral pneumonia cohort,children in the COVID-19 cohort were mostly exposed to family members confirmed to have COVID-19(53/64 vs.23/284),were of older median age(6.3 years vs.3.2 years),and had a higher proportion of ground-glass opacity(GGO)on computed tomography(18/40 vs.0/38,P<0.001).Children in the COVID-19 pneumonia cohort had a lower proportion of severe cases(1/40 vs.38/284,P=0.048),and lower cases with high fever(3/40 vs.167/284,P<0.001),requiring intensive care(1/40 vs.32/284,P<0.047)and with shorter symptomatic duration(median 5d vs.8d,P<0.001).The proportion of cases with evaluated inflammatory indicators,biochemical indicators related to organ or tissue damage,D-dimer and secondary bacterial infection were lower in the COVID-19 pneumonia cohort than those in the viral pneumonia cohort(P<0.05).No statistical differences were found in the duration of positive PCR results from pharyngeal swabs in 25 children with COVID-19 who received antiviral drugs(lopinavir-ritonavir,ribavirin,and arbidol)as compared with duration in 39 children without antiviral therapy(median 10d vs.9d,P=0.885).Conclusions:The symptoms and severity of COVID-19 pneumonia in children were no more severe than those in children with other viral pneumonia.Lopinavir-ritonavir,ribavirin and arbidol do not shorten the duration of positive PCR results from pharyngeal swabs in children with COVID-19.During the COVID-19 outbreak,attention also must be given to children with infection by other pathogens infection. 展开更多
关键词 CHILDREN Severe acute respiratory syndrome Coronavirus disease-2019 Viral pneumonia
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Kaposiform Hemangioendothelioma: Case Report and Literature Review 被引量:3
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作者 Gang Zhou Shuhua Yang +5 位作者 Xiu Nie Jingyuan Du Jin Li Jianxiang Liu Renhao Ze yu he 《Chinese Journal of Clinical Oncology》 CSCD 2007年第4期288-292,共5页
Kaposiform hemangioendothelioma (KHE) is a rare locally ag- gressive vascular tumor that mainly occurs in children and early adolescents. It is often associated with the Kasabach-Meritt phenomenon which is marked by... Kaposiform hemangioendothelioma (KHE) is a rare locally ag- gressive vascular tumor that mainly occurs in children and early adolescents. It is often associated with the Kasabach-Meritt phenomenon which is marked by severe thrombocytopenia and a variable degree of anemia. The tumor mostly is located in the superficial or deep soft tissue mass of the extremities. Herein, we report an unusual case of kaposiform hemangioendothelioma that, 展开更多
关键词 HISTOPATHOLOGY kaposiform hemangioendo- thelioma BONE vascular tumors.
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Application of multiple Roux-en-Y hepaticojejunostomy reconstruction by formation of bile hilar duct lake in the operation of hilar cholangiocarcinoma 被引量:2
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作者 Xiao-Jun Yang Xiao-Hua Dong +5 位作者 Shi-Yong Chen Biao Wu yu he Bao-Long Dong Bing-Qiang Ma Peng Gao 《World Journal of Clinical Cases》 SCIE 2020年第1期68-75,共8页
BACKGROUND Hilar cholangiocarcinoma is the most common malignant tumor of the extrahepatic bile duct.Until now,radical resection has been the most effective method for the long-term survival of patients with the disea... BACKGROUND Hilar cholangiocarcinoma is the most common malignant tumor of the extrahepatic bile duct.Until now,radical resection has been the most effective method for the long-term survival of patients with the disease.However,many problems have emerged in the field of hepatobiliary surgery for a long time,including complex surgical procedures,low resection rate,and postoperative complications.We have adopted the“multiple Roux-en-Y hepaticojejunostomy reconstruction by formation of a bile duct lake”technique in the treatment of hilar cholangiocarcinoma since 2008,and obtained satisfactory short-and longterm results.AIM To examine the feasibility of the application of multiple Roux-en-Y hepaticojejunostomy reconstruction by formation of a bile duct lake in the operation of hilar cholangiocarcinoma METHODS A retrospective analysis was performed for the clinical data,surgical methods,and results of 76 patients with hilar cholangiocarcinoma who were treated with hilar bile duct lake-forming multiple Roux-en-Y hepaticojejunostomy reconstruction at Gansu Provincial Hospital.RESULTS In all 76 cases,the operation was successful and no operative death occurred.The mean(range)operation time was 215.4±53.5 min(124–678 min),and the amount of bleeding during the operation was 428.2±63.8 mL(240–2200 mL).The overall 1-year survival rate was 78.9%,and the 3-year survival rate was 32.8%.CONCLUSION The multiple Roux-en-Y hepaticojejunostomy reconstruction technique with formation of a bile duct lake is safe and effective for the surgical treatment of hilar cholangiocarcinoma. 展开更多
关键词 Hilar cholangiocarcinoma Bile duct lake HEPATICOJEJUNOSTOMY
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Metabolomics: A useful tool for ischemic stroke research 被引量:1
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作者 Wentao Li Chongyu Shao +5 位作者 Chang Li Huifen Zhou Li yu Jiehong Yang Haitong Wan yu he 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第9期968-983,共16页
Ischemic stroke(IS)is a multifactorial and heterogeneous disease.Despite years of studies,effective strategies for the diagnosis,management and treatment of stroke are still lacking in clinical practice.Metabolomics i... Ischemic stroke(IS)is a multifactorial and heterogeneous disease.Despite years of studies,effective strategies for the diagnosis,management and treatment of stroke are still lacking in clinical practice.Metabolomics is a growing field in systems biology.It is starting to show promise in the identification of biomarkers and in the use of pharmacometabolomics to help patients with certain disorders choose their course of treatment.The development of metabolomics has enabled further and more biological applications.Particularly,metabolomics is increasingly being used to diagnose diseases,discover new drug targets,elucidate mechanisms,and monitor therapeutic outcomes and its potential effect on precision medicine.In this review,we reviewed some recent advances in the study of metabolomics as well as how metabolomics might be used to identify novel biomarkers and understand the mechanisms of IS.Then,the use of metabolomics approaches to investigate the molecular processes and active ingredients of Chinese herbal formulations with anti-IS capabilities is summarized.We finally summarized recent developments in single cell metabolomics for exploring the metabolic profiles of single cells.Although the field is relatively young,the development of single cell metabolomics promises to provide a powerful tool for unraveling the pathogenesis of IS. 展开更多
关键词 Metabolomics Ischemic stroke BIOMARKER Precision medicine Single cell metabolomics
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基于非监督对比学习的火星地形特征提取方法 被引量:1
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作者 杨博 魏翔 +1 位作者 于贺 刘超凡 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第6期1842-1849,共8页
火星表面地形智能识别对火星车自主探测具有重要意义,火星地形图像的特征提取方法目前主要分为传统的浅层视觉特征提取和基于监督学习的深层特征提取2类。找回丢失图像信息、获取大量带标签数据是要解决的关键问题。为此,提出一种基于... 火星表面地形智能识别对火星车自主探测具有重要意义,火星地形图像的特征提取方法目前主要分为传统的浅层视觉特征提取和基于监督学习的深层特征提取2类。找回丢失图像信息、获取大量带标签数据是要解决的关键问题。为此,提出一种基于非监督对比学习的火星地形特征识别方法,通过建立图像字典数据集,用“问询”和“编码”2组神经网络分别将单个图像与“字典”数据集中其他图像进行对比,用相似度泛函作为损失函数对网络进行训练,从而实现对火星地形图像的特征识别。所提方法还具有对训练数据集之外的新类型地形图像识别能力,后续识别分类优越性突出。仿真结果表明:所提方法识别准确率为85.4%,对新类型地形图像的识别准确率为84.5%。 展开更多
关键词 对比学习 非监督 深度学习 火星地形 特征提取
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A design of resonant cavity with an improved coupling-adjusting mechanism for the W-band EPR spectrometer 被引量:1
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作者 yu he Runqi Kang +2 位作者 Zhifu Shi Xing Rong Jiangfeng Du 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期115-120,共6页
We report a new design of resonant cavity for a W-band electron paramagnetic resonance(EPR)spectrometer.An improved coupling-adjusting mechanism,which is robust,compact,and suits with both solenoid-type and split-pair... We report a new design of resonant cavity for a W-band electron paramagnetic resonance(EPR)spectrometer.An improved coupling-adjusting mechanism,which is robust,compact,and suits with both solenoid-type and split-pair magnets,is utilized on the cavity,and thus enables both continuous-wave(CW)and pulsed EPR experiments.It is achieved by a tiny metal cylinder in the iris.The coupling coefficient can be varied from 0.2 to 17.9.Furthermore,two pistons at each end of the cavity allow for adjustment of the resonant frequency.A horizontal TE_(011) geometry also makes the cavity compatible with the two frequently used types of magnets.The coupling-varying ability has been demonstrated by reflection coefficient(S_(11))measurement.CW and pulsed EPR experiments have been conducted.The performance data indicates a prospect of wide applications of the cavity in fields of physics,chemistry and biology. 展开更多
关键词 electron paramagnetic resonance W-BAND microwave cavity coupling coefficient
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Impact of the mass isotope on plasma confinement and transport properties in the HL-2A tokamak 被引量:1
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作者 yu he Jun CheNG +12 位作者 yuhong XU Qian FANG yucai LI Jianqiang XU Weice WANG Longwen YAN Zhihui HUANG Na WU Min JIANG Zhongbing SHI Yi LIU Wulyu ZHONG Min XU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第9期31-36,共6页
The impact of the mass isotope on plasma conflnement and transport properties has been investigated in Ohmically-heated hydrogen and deuterium plasmas in the HL-2 A tokamak.Experimental results show that under similar... The impact of the mass isotope on plasma conflnement and transport properties has been investigated in Ohmically-heated hydrogen and deuterium plasmas in the HL-2 A tokamak.Experimental results show that under similar discharge parameters the deuterium plasma has better conflnement and lower turbulent transport than the hydrogen one,and concomitantly,it is found that the magnitude of geodesic acoustic mode zonal flows,the tilting angle of the Reynolds stress tensor and the turbulence correlation lengths are all larger in the edge region of the deuterium plasma.The results provide direct experimental evidence on the importance of the nonlinear energy coupling between ambient turbulence and zonal flows for governing the isotope effects in fusion plasmas. 展开更多
关键词 isotope effect conflnement and transport turbulence and zonal flows
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A Data-Driven Oil Production Prediction Method Based on the Gradient Boosting Decision Tree Regression 被引量:1
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作者 Hongfei Ma Wenqi Zhao +1 位作者 yurong Zhao yu he 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1773-1790,共18页
Accurate prediction ofmonthly oil and gas production is essential for oil enterprises tomake reasonable production plans,avoid blind investment and realize sustainable development.Traditional oil well production trend... Accurate prediction ofmonthly oil and gas production is essential for oil enterprises tomake reasonable production plans,avoid blind investment and realize sustainable development.Traditional oil well production trend prediction methods are based on years of oil field production experience and expertise,and the application conditions are very demanding.With the rapid development of artificial intelligence technology,big data analysis methods are gradually applied in various sub-fields of the oil and gas reservoir development.Based on the data-driven artificial intelligence algorithmGradient BoostingDecision Tree(GBDT),this paper predicts the initial single-layer production by considering geological data,fluid PVT data and well data.The results show that the GBDT algorithm prediction model has great accuracy,significantly improving efficiency and strong universal applicability.The GBDTmethod trained in this paper can predict production,which is helpful for well site optimization,perforation layer optimization and engineering parameter optimization and has guiding significance for oilfield development. 展开更多
关键词 Gradient boosting decision tree production prediction data analysis
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Giant hemangioma of the caudate lobe of the liver with surgical treatment:A case report 被引量:1
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作者 Xin-Xin Wang Bao-Long Dong +3 位作者 Biao Wu Shi-Yong Chen yu he Xiao-Jun Yang 《World Journal of Clinical Cases》 SCIE 2021年第21期5980-5987,共8页
BACKGROUND Caudate lobe hemangioma of the liver is relatively rare.Due to the unique anatomical location of the caudate lobe,the caudate lobectomy accounts for only 0.5%to 4%of hepatic resection,which is difficult to ... BACKGROUND Caudate lobe hemangioma of the liver is relatively rare.Due to the unique anatomical location of the caudate lobe,the caudate lobectomy accounts for only 0.5%to 4%of hepatic resection,which is difficult to operate and takes a long time,and even has many postoperative complications.CASE SUMMARY A 34-year-old female presented with a 1 year history of intermittent pain in the right side of the waist without obvious inducement.All laboratory blood tests were within normal limits.Indocyanine green 15 min retention was rated 2.9%,and Child-Pugh was rated A.Computed tomography and magnetic resonance imaging diagnosed giant hemangioma of the caudate lobe with hemangioma of left lobe of liver.After discussion,surgical treatment was performed,which lasted 410 min,with intraoperative bleeding of about 600 mL and postoperative pathological findings of cavernous hemangioma.There were no obvious postoperative complications,and the patient was discharged 10 d after surgery.CONCLUSION Caudate lobectomy is difficult due to its special anatomical location.Under the condition of fully exposing the anatomy of the first porta hepatis,the second porta hepatis,the third porta hepatis,the fourth porta hepatis and middle hepatic vein and combining with the Pringle maneuver,caudate lobectomy can be performed in a precise and safe process. 展开更多
关键词 Caudate lobe hemangioma Caudate lobectomy Case report
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Increased KIF21B expression is a potential prognostic biomarker in hepatocellular carcinoma 被引量:1
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作者 Hui-Qi Zhao Bao-Long Dong +5 位作者 Min Zhang Xiao-Hua Dong yu he Shi-Yong Chen Biao Wu Xiao-Jun Yang 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2020年第3期276-288,共13页
BACKGROUND The kinesin superfamily protein member KIF21B plays an important role in regulating mitotic progression;however,the function and mechanisms of KIF21B in cancer,particularly in hepatocellular carcinoma(HCC),... BACKGROUND The kinesin superfamily protein member KIF21B plays an important role in regulating mitotic progression;however,the function and mechanisms of KIF21B in cancer,particularly in hepatocellular carcinoma(HCC),are unknown.AIM To explore the role of KIF21B in hepatocellular carcinoma and its effect on prognosis after hepatectomy.METHODS First,data on the differential expression of KIF21B in patients with HCC from The Cancer Genome Atlas database was analyzed.Subsequently,the expression levels of KIF21B in HCC cell lines and hepatocytes were detected by reverse transcription-polymerase chain reaction,and its biological effect on BEL-7404 cells was evaluated by KIF21B knockdown.Immunohistochemical analysis was used to validate the differential expression of KIF21B in HCC tissues and adjacent normal tissues from 186 patients with HCC after hepatectomy.The Kaplan-Meier method was used to assess prognosis significance.RESULTS KIF21B expression levels were significantly higher in HCC tissues than in corresponding adjacent normal tissues.The expression levels of KIF21B in four HCC cell lines were higher than that in normal liver cells.Functional experiments showed that KIF21B knockdown remarkably suppressed cell proliferation and induced apoptosis.Moreover,immunohistochemistry results are consistent with The Cancer Genome Atlas analysis,with KIF21B expression levels being increased in HCC tissues compared to adjacent normal tissues.Univariate and multivariate analyses revealed KIF21B as an independent risk factor for overall survival and disease-free survival in patients with HCC after hepatectomy.CONCLUSION Taken together,our results provide evidence that KIF21B plays an important role in HCC progression and may be a potential diagnostic and prognostic marker for HCC. 展开更多
关键词 Hepatocellular carcinoma KIF21B PROLIFERATION APOPTOSIS PROGNOSIS
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一种高超声速飞行器雷达测角误差的分析方法
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作者 杨博 刘超凡 +2 位作者 于贺 魏翔 樊子辰 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第12期3666-3676,共11页
雷达回波穿过大气、飞行器外流场、天线罩后产生的波前畸变对主动雷达单脉冲测角误差有着重要影响。基于此,分析了湍流结构引起的折射率梯度对于波前畸变影响及网格分辨率对波动方程弱形式数值求解精度,提出电磁波动方程弱形式“显式”... 雷达回波穿过大气、飞行器外流场、天线罩后产生的波前畸变对主动雷达单脉冲测角误差有着重要影响。基于此,分析了湍流结构引起的折射率梯度对于波前畸变影响及网格分辨率对波动方程弱形式数值求解精度,提出电磁波动方程弱形式“显式”梯度项修正及涡球模型补充密度场小尺度结构的“梯度重构”方法,通过有限元方法进行了计算机数值仿真。仿真结果表明:雷达测角误差的重要原因之一是小尺度湍流造成的电场畸变,并且随着涡结构尺度减小、波长变长,电场畸变加强,测角误差加大。 展开更多
关键词 雷达测角 高超声速飞行器 电磁波动方程 弱形式 有限元方法
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Analysis of the Influence of the Self-efficacy of College Students on Their Response Behaviors Toward COVID-19 被引量:1
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作者 Ju-Hua Liu Yan-Ni Mao +3 位作者 yu he Pei-Pei Bai Jing Ouyang Jing Zhang 《Psychosomatic Medicine Research》 2021年第4期175-182,共8页
Objective:This study aims to investigate the self-efficacy of college students during the Coronavirus disease 2019(COVID-19)pandemic and to conduct an empirical analysis on its influence mechanism on decision-making a... Objective:This study aims to investigate the self-efficacy of college students during the Coronavirus disease 2019(COVID-19)pandemic and to conduct an empirical analysis on its influence mechanism on decision-making and coping skills to provide reference for decision support to improve the coping behavior of college students during public health emergencies.Methods:The study recruited a total of 1,346 college students in Shaanxi.Data were collected via a questionnaire and analyzed using SPSS 22.0 and AMOS 22.0.Result:The self-efficacy of the college students exerted a significantly positive impact on their coping decisions(β=0.754)and coping skills(β=0.822)during the COVID-19 pandemic.Both passed the significance test at a 99.9%confidence interval(99%CI).Conclusion:During the COVID-19 pandemic,improving the self-efficacy of college students can significantly positively influence their coping behaviors.Therefore,providing effective interventions that target the self-efficacy of college students and encouraging them to adopt positive coping behaviors is necessary. 展开更多
关键词 COVID-19 SELF-EFFICACY Coping decisions Coping skills Structural equation model
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