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Prevalences and causes of vision impairment in elderly Chinese: a socioeconomic perspective of a comparative report nested in Jiangsu Eye Study 被引量:6
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作者 Rong-Rong Zhu jian shi +1 位作者 Mei Yang Huai-Jin Guan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第7期1051-1056,共6页
AIM:To survey the prevalence and causes of visual impairment/blindness among elderly Chinese from different socioeconomic status in community-based design.METHODS:Cluster-sampling randomly selected residents from Bi... AIM:To survey the prevalence and causes of visual impairment/blindness among elderly Chinese from different socioeconomic status in community-based design.METHODS:Cluster-sampling randomly selected residents from Binhu and Funing District,two areas representing different socioeconomic levels in China with Binhu in an advanced status and Funing in lessdeveloped area.The participants subjected to ophthalmic examination.The presenting visual acuity(PVA) and best-corrected visual acuity(BCVA) were recorded.Visual impairment and blindness were defined according to World Health Organization criteria.The causes of visual impairment/blindness were identified by ophthalmic examination and/or questionnaire.The socioeconomic status included the per capita gross domestic product,numbers of hospital with ophthalmic service and the number of ophthalmologists per 1 million residents.RESULTS:We successfully included 12 867 participants form 2 areas in this study.The prevalence of PVA impairment(〈20/63 to ≥20/400) in the better eye was 5.4% in Binhu and 23.6% in Funing,while the prevalence of blindness(〈20/400) was 0.9% in Binhu and 2.3% in Funing.With BCVA,the prevalence of visual impairment was 2.4% in Binhu and 6.4% in Funing,while the prevalence of blindness was 0.8% in Binhu and 1.6% in Funing.The participants with older age and female gender had higher prevalence in visual impairment and blindness.The highest prevalences of vision impairment and blindness evaluated by BCVA at 〉80y age group reached 20.4% and 6.3% respectively.The prevalences of vision impairment and blindness evaluated by BCVA were 3.5% and 1.0% in male and 5.0% and 1.3% in female.The above differences were statistically significant(P〈0.05).The predominant causes of visual impairment and blindness were cataract,retinal disorders and uncorrected refractive error in both areas.The socioeconomic status was associated with visual impairment and blindness.CONCLUSION:This community-based study build a sufficient sample size for an ophthalmic survey.Our data show the disparities on socioeconomic development and genders in visual impairment and blindness in China.Special emphasis of ophthalmic service should be placed on females and less-developed area. 展开更多
关键词 blindness vision impairment prevalence community-based socioeconomic development
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PD-1抑制剂联合化疗对比贝伐珠单抗联合化疗一线治疗非鳞非小细胞肺癌的研究
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作者 郑飞 李曙光 +2 位作者 黄芳 史健 刘义冰 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第15期769-774,共6页
目的比较细胞程序性死亡受体-1(programmed cell death protein-1,PD-1)抑制剂联合化疗与贝伐珠单抗联合化疗一线治疗晚期非鳞非小细胞肺癌(non-squamous non-small cell lung cancer,nsNSCLC)的疗效。方法回顾性收集2014年11月至2024年... 目的比较细胞程序性死亡受体-1(programmed cell death protein-1,PD-1)抑制剂联合化疗与贝伐珠单抗联合化疗一线治疗晚期非鳞非小细胞肺癌(non-squamous non-small cell lung cancer,nsNSCLC)的疗效。方法回顾性收集2014年11月至2024年3月于河北医科大学第四医院接受一线治疗的晚期nsNSCLC患者237例。根据治疗方案分为PD-1抑制剂联合化疗(IC组)119例和贝伐珠单抗联合化疗(BC组)118例。采用倾向得分匹配(propensity score matching,PSM)平衡协变量。研究主要终点为无进展生存期(progression-free survival,PFS),次要终点为客观缓解率(objective response rate,ORR)、疾病控制率(disease control rate,DCR)、总生存期(overall survival,OS)。结果237例患者经PSM后IC组和BC组各87例,IC组和BC组的ORR分别为31.0%(27/87)和43.7%(38/87)(P=0.085),DCR为96.6%(84/87)和95.4%(83/87)(P=1.000)。中位PFS IC组为9.3个月,BC组为9.1个月,两组差异无统计学意义(P=0.053)。OS两组差异无统计学意义(两组均未达到中位OS,P=0.116)。结论PD-1抑制剂联合化疗对比贝伐珠单抗联合化疗一线治疗晚期nsNSCLC近期疗效无差异。 展开更多
关键词 PD-1抑制剂 贝伐珠单抗 非鳞非小细胞肺癌
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Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion 被引量:1
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作者 Yan-peng Wei Huai-qian Li +7 位作者 Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang Cheng jian shi Zhi-quan Miao Bo Yu Feng Lin 《China Foundry》 SCIE EI CAS CSCD 2024年第4期327-333,共7页
Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships.However,it... Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships.However,its vibration and noise reduction,and damping properties have not been fully studied.Therefore,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static compression.The modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal tests.For the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,respectively.The results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity. 展开更多
关键词 lattice metamaterials TPMS energy absorption DAMPING laser powder bed fusion
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Advancements in machine learning for material design and process optimization in the field of additive manufacturing
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作者 Hao-ran Zhou Hao Yang +8 位作者 Huai-qian Li Ying-chun Ma Sen Yu jian shi Jing-chang Cheng Peng Gao Bo Yu Zhi-quan Miao Yan-peng Wei 《China Foundry》 SCIE EI CAS CSCD 2024年第2期101-115,共15页
Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric challenges.However,the development of additive manufacturing process is co... Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric challenges.However,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high costs.Machine learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new techniques.This paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process development.Firstly,it introduces the background and significance of machine learning-assisted design in additive manufacturing process.It then further delves into the application of machine learning in additive manufacturing,focusing on model design and process guidance.Finally,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing. 展开更多
关键词 additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning
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Machine-Learning-Assisted Design of Deep Eutectic Solvents Based on Uncovered Hydrogen Bond Patterns
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作者 Usman L.Abbas Yuxuan Zhang +4 位作者 Joseph Tapia Selim Md Jin Chen jian shi Qing Shao 《Engineering》 SCIE EI CAS CSCD 2024年第8期74-83,共10页
Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a... Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a lack of efficient tools that accurately predict DES formation.The search for DES relies heavily on intuition or trial-and-error processes,leading to low success rates or missed opportunities.Recognizing that hydrogen bonds(HBs)play a central role in DES formation,we aim to identify HB features that distinguish DES from non-DES systems and use them to develop machine learning(ML)models to discover new DES systems.We first analyze the HB properties of 38 known DES and 111 known non-DES systems using their molecular dynamics(MD)simulation trajectories.The analysis reveals that DES systems have two unique features compared to non-DES systems:The DESs have①more imbalance between the numbers of the two intra-component HBs and②more and stronger inter-component HBs.Based on these results,we develop 30 ML models using ten algorithms and three types of HB-based descriptors.The model performance is first benchmarked using the average and minimal receiver operating characteristic(ROC)-area under the curve(AUC)values.We also analyze the importance of individual features in the models,and the results are consistent with the simulation-based statistical analysis.Finally,we validate the models using the experimental data of 34 systems.The extra trees forest model outperforms the other models in the validation,with an ROC-AUC of 0.88.Our work illustrates the importance of HBs in DES formation and shows the potential of ML in discovering new DESs. 展开更多
关键词 Machine learning Deep eutectic solvents Molecular dynamics simulations Hydrogen bond Molecular design
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Solvent-Resistant Wearable Triboelectric Nanogenerator for Energy-Harvesting and Self-Powered Sensors
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作者 Yongtao Yu Yuelin Yu +7 位作者 Hongyi Wu Tianshuo Gao Yi Zhang Jiajia Wu Jiawei Yan jian shi Hideaki Morikawa Chunhong Zhu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第5期376-386,共11页
Wearable triboelectric nanogenerators(TENGs)have attracted attention owing to their ability to harvest energy from the surrounding environment without maintenance.Herein,polyetherimide-Al_(2)O_(3)(PAl)and polyvinylide... Wearable triboelectric nanogenerators(TENGs)have attracted attention owing to their ability to harvest energy from the surrounding environment without maintenance.Herein,polyetherimide-Al_(2)O_(3)(PAl)and polyvinylidene fluoride-co-hexafluoropropylene(PVDF-HFP,PH)nanofiber membranes were used as tribo-positive and tribo-negative materials,respectively.Phytic acid-doped polyaniline(PANI)/cotton fabric(PPCF)and ethylenediamine(EDA)-crosslinked PAl(EPAl)nanofiber membranes were used as triboelectrode and triboencapsulation materials,respectively.The result showed that when the PAl-PH-based TENG was shaped as a circle with a radius of 1 cm,under the pressure of 50 N,and the frequency of 0.5 Hz,the open-circuit voltage(V_(oc))and short-circuit current(I_(sc))reached the highest value of 66.6 V and-93.4 to 110.1 nA,respectively.Moreover,the PH-based TENG could be used as a fabric sensor to detect fabric composition and as a sensor-inductive switch for light bulbs or beeping warning devices.When the PAl-PH-based TENG was shaped as a 5×5 cm^(2)rectangle,a 33 pF capacitor could be charged to 15 V in 28 s.Interestingly,compared to PAl nanofiber membranes,EPAl nanofiber membranes exhibited good dyeing properties and excellent solvent resistance.The PPCF exhibited<5%resistance change after washing,bending,and stretching. 展开更多
关键词 energy-harvesting power supply SENSORS solvent-resistant wearable triboelectric nanogenerator
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Study on the Impact of Massive Refracturing on the Fracture Network in Tight Oil Reservoir Horizontal Wells
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作者 jianchao shi Yanan Zhang +2 位作者 Wantao Liu Yuliang Su jian shi 《Fluid Dynamics & Materials Processing》 EI 2024年第5期1147-1163,共17页
Class III tight oil reservoirs have low porosity and permeability,which are often responsible for low production rates and limited recovery.Extensive repeated fracturing is a well-known technique to fix some of these ... Class III tight oil reservoirs have low porosity and permeability,which are often responsible for low production rates and limited recovery.Extensive repeated fracturing is a well-known technique to fix some of these issues.With such methods,existing fractures are refractured,and/or new fractures are created to facilitate communication with natural fractures.This study explored how different refracturing methods affect horizontal well fracture networks,with a special focus on morphology and related fluid flow changes.In particular,the study relied on the unconventional fracture model(UFM).The evolution of fracture morphology and flow field after the initial fracturing were analyzed accordingly.The simulation results indicated that increased formation energy and reduced reservoir stress differences can promote fracture expansion.It was shown that the length of the fracture network,the width of the fracture network,and the complexity of the fracture can be improved,the oil drainage area can be increased,the distance of oil and gas seepage can be reduced,and the production of a single well can be significantly increased. 展开更多
关键词 Type III tight oil reservoirs refracturing methods horizontal wells fracture network study fracture network evolution
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Synthesizing high-resolution satellite salinity data based on multi-fractal fusion
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作者 Hengqian Yan jian shi +3 位作者 Ren Zhang Wangjiang Hu Yongchui Zhang Mei Hong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期112-124,共13页
The spaceborne platform has unprecedently provided the global eddy-permitting(typically about 0.25°)products of sea surface salinity(SSS),however the existing SSS products can hardly resolve mesoscale motions due... The spaceborne platform has unprecedently provided the global eddy-permitting(typically about 0.25°)products of sea surface salinity(SSS),however the existing SSS products can hardly resolve mesoscale motions due to the heavy noises therein and the over-smoothing in denoising processes.By means of the multi-fractal fusion(MFF),the high-resolution SSS product is synthesized with the template of sea surface temperature(SST).Two low-resolution SSS products and four SST products are considered as the source data and the templates respectively to determine the best combination.The fused products are validated by the in situ observations and intercompared via SSS maps,Singularity Exponent maps and wavenumber spectra.The results demonstrate that the MFF can perform a good work in mitigating the noises and improving the resolution.The combination of the climate change initiative SSS and the remote sensing system SST can produce the 0.1°denoised product whose global mean standard derivation of salinity against Argo is 0.21 and the feature resolution can reach 30−40 km. 展开更多
关键词 sea surface salinity multi-fractal fusion high resolution
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外伤性感染性眼内炎患者脱盲因素研究 被引量:4
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作者 唐秋阳 施健 +3 位作者 张俊芳 张淑丹 桑爱民 石海红 《国际眼科杂志》 CAS 北大核心 2022年第8期1402-1406,共5页
目的:探讨影响外伤性感染性眼内炎(PTIE)患者脱盲的因素。方法:回顾性分析2010-01/2020-12在南通大学附属医院眼科就诊的PTIE患者169例169眼临床资料。患者接受玻璃体腔注射抗生素(IVIA)和/或玻璃体切除术(PPV)治疗后,末次随访最佳矫正... 目的:探讨影响外伤性感染性眼内炎(PTIE)患者脱盲的因素。方法:回顾性分析2010-01/2020-12在南通大学附属医院眼科就诊的PTIE患者169例169眼临床资料。患者接受玻璃体腔注射抗生素(IVIA)和/或玻璃体切除术(PPV)治疗后,末次随访最佳矫正视力(BCVA)≥0.05为脱盲组(103眼)和BCVA<0.05为单眼盲组(66眼),分析影响患者脱盲的因素。结果:PTIE患者治疗后脱盲率为53.5%。单因素分析显示治疗前BCVA≥手动、不伴有视网膜脱离、眼内炎眼底分级<3级以及未培养出毒力强微生物是患者脱盲的有利因素(P<0.05);多因素Logistic分析显示治疗前BCVA分两组,BCVA≥手动(OR=0.253, 95%CI:0.108~0.592)以及不伴有视网膜脱离(OR=0.241, 95%CI:0.103~0.564)是患者脱盲的有利因素。结论:治疗前BCVA较好、不伴有视网膜脱离、眼内炎眼底分级<3级以及未感染毒力强微生物是PTIE患者最终脱盲的有利因素。 展开更多
关键词 眼内炎 开放性眼外伤 预后
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FS-LASIK与ICL植入术后临床疗效的Meta分析 被引量:2
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作者 时健 陈立浩 +2 位作者 刘倩宏 姚小磊 彭清华 《国际眼科杂志》 CAS 北大核心 2021年第3期480-486,共7页
目的:比较FS-LASIK与ICL植入术治疗近视的临床疗效。方法:计算机检索2015-01/2020-01中国知网数据库、万方数据库、重庆维普中文科技期刊全文数据库、中国生物医学文献数据库(CBM)、Cochrane Library、PubMed、MEDLINE等数据库关于采用F... 目的:比较FS-LASIK与ICL植入术治疗近视的临床疗效。方法:计算机检索2015-01/2020-01中国知网数据库、万方数据库、重庆维普中文科技期刊全文数据库、中国生物医学文献数据库(CBM)、Cochrane Library、PubMed、MEDLINE等数据库关于采用FS-LASIK与ICL植入术治疗近视的临床对照研究相关文献,使用Rev-man5.3统计软件进行Meta分析和统计处理。结果:共纳入11项研究,患者673例1301眼。Meta分析结果显示,FS-LASIK与ICL植入术后的安全性指数(术后最佳矫正视力/术前最佳矫正视力)、客观视觉质量、等效球镜度、柱镜度、球镜度、三叶草像差、彗差均无差异,但与ICL植入术相比,FS-LASIK术后有效性指数(术后裸眼视力/术前最佳矫正视力)较高,引入的总高阶像差和球差大,对比敏感度下降。结论:FS-LASIK较ICL植入术后总高阶像差、球差引入较大,对比敏感度下降,ICL植入术较FS-LASIK的临床疗效更具优势。 展开更多
关键词 飞秒激光制瓣的准分子激光原位角膜磨镶术 有晶状体眼后房型人工晶状体植入术 有效性 安全性
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Sophocarpine attenuates liver fibrosis by inhibiting the TLR4 signaling pathway in rats 被引量:20
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作者 Hui Qian jian shi +6 位作者 Ting-Ting Fan Jiao Lv Si-Wen Chen Chun-Yan Song Zhi-Wu Zheng Wei-Fen Xie Yue-Xiang Chen 《World Journal of Gastroenterology》 SCIE CAS 2014年第7期1822-1832,共11页
AIM: To explore the effect of sophocarpine on experimental liver fibrosis and the potential mechanism involved.
关键词 Liver fibrosis SOPHOCARPINE Toll-like receptor 4 Hepatic stellate cells CYTOKINES
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Endoscopic ultrasound elastography for differentiating between pancreatic adenocarcinoma and inflammatory masses:A meta-analysis 被引量:6
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作者 Xiang Li Wei Xu +2 位作者 jian shi Yong Lin Xin Zeng 《World Journal of Gastroenterology》 SCIE CAS 2013年第37期6284-6291,共8页
AIM:To evaluate the accuracy of endoscopic ultrasound(EUS)elastography for differentiating between pancreatic ductal adenocarcinoma(PDAC)and pancreatic inflammatory masses(PIM).METHODS:Electronic databases(updated to ... AIM:To evaluate the accuracy of endoscopic ultrasound(EUS)elastography for differentiating between pancreatic ductal adenocarcinoma(PDAC)and pancreatic inflammatory masses(PIM).METHODS:Electronic databases(updated to December 2012)and manual bibliographical searches were carried out.A meta-analysis of all diagnostic clinical trials evaluating the accuracy of EUS elastography in differentiating PDAC from PIM was conducted.Heterogeneity was assessed among the studies.The metaanalysis was performed to evaluate the accuracy of EUS elastography in differentiating PDAC from PIM in homogeneous studies.RESULTS:Ten studies involving 781 patients were included in the analysis.Significant heterogeneity in sensitivity was observed among the studies(Cochran Q test=24.16,df=9,P=0.0041,I2=62.8%),while heterogeneity in specificity was not observed(Cochran Q test=5.93,df=9,P=0.7473,I2=0.0%).The area under the curve under the Sports Rights Owners Coalition was 0.8227.Evaluation of heterogeneity suggested that the different diagnostic standards used in the included studies were the source of heterogeneity.In studies using the color pattern as the diagnostic standard,the pooled sensitivity,specificity,positive likelihood ratio(LR),negative LR and diagnostic OR were0.99(0.97-1.00),0.76(0.67-0.83),3.36(2.39-4.72),0.03(0.01-0.07)and 129.96(47.02-359.16),respectively.In studies using the hue histogram as the diagnostic standard,the pooled sensitivity,specificity,positive LR,negative LR and diagnostic OR were 0.92(0.89-0.95),0.68(0.57-0.78),2.84(2.05-3.93),0.12(0.08-0.19)and 24.69(12.81-47.59),respectively.CONCLUSION:EUS elastography is a valuable method for the differential diagnosis between PDAC and PIM.And a preferable diagnostic standard should be explored and improvements in specificity are required. 展开更多
关键词 ENDOSCOPIC ultrasound ELASTOGRAPHY PANCREATIC ADENOCARCINOMA META-ANALYSIS
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Prospective prediction and exploration situation of marine Mesozoic-Paleozoic oil and gas in the South Yellow Sea 被引量:10
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作者 jian-wen Chen Ming Xu +9 位作者 Bao-hua Lei Jie Liang Yin-guo Zhang Shu-yu Wu jian shi Yong Yuan jian-qiang Wang Yu-xi Zhang Gang Li Wen-juan Wang 《China Geology》 2019年第1期67-84,共18页
The South Yellow Sea Basin is a large sedimentary basin superimposed by the Mesozoic-Paleozoic marine sedimentary basin and the Mesozoic-Cenozoic terrestrial sedimentary basin, where no oil and gas fields have been di... The South Yellow Sea Basin is a large sedimentary basin superimposed by the Mesozoic-Paleozoic marine sedimentary basin and the Mesozoic-Cenozoic terrestrial sedimentary basin, where no oil and gas fields have been discovered after exploration for 58 years. After the failure of oil and gas exploration in terrestrial basins, the exploration target of the South Yellow Sea Basin turned to the marine Mesozoic- Paleozoic strata. After more than ten years' investigation and research, a lot of achievements have been obtained. The latest exploration obtained effective seismic reflection data of deep marine facies by the application of seismic exploration technology characterized by high coverage, abundant low-frequency components and strong energy source for the deep South Yellow Sea Basin. In addition, some wells drilled the Middle-Upper Paleozoic strata, with obvious oil and gas shows discovered in some horizons. The recent petroleum geological research on the South Yellow Sea Basin shows that the structure zoning of the marine residual basin has been redetermined, the basin structure has been defined, and 3 seismic reflection marker layers are traceable and correlatable in the residual thick Middle-Paleozoic strata below the continental Meso-Cenozoic strata in the South Yellow Sea Basin. Based on these, the seismic sequence of the marine sedimentary strata was established. According to the avaliable oil and gas exploration and research, the marine Mesozoic-Paleozoic oil and gas prospects of the South Yellow Sea were predicted as follows.(1) The South Yellow Sea Basin has the same sedimentary formation and evolution history during the sedimentary period of the Middle-Paleozoic marine basin with the Sichuan Basin.(2) There are 3 regional high-quality source rocks.(3) The carbonate and clastic reservoirs are developed in the Mesozoic- Paleozoic strata.(4) The three source-reservoir-cap assemblages are relatively intact.(5) The Laoshan Uplift is a prospect area for the Lower Paleozoic oil and gas, and the Wunansha Uplift is one for the marine Upper Paleozoic oil and gas.(6) The Gaoshi stable zone in the Laoshan Uplift is a favorable zone.(7) The marine Mesozoic-Paleozoic strata in the South Yellow Sea Basin has the geological conditions required to form large oil and gas fields, with remarkable oil and gas resources prospect. An urgent problem to be addressed now within the South Yellow Sea Basin is to drill parametric wells for the Lower Paleozoic strata as the target, to establish the complete stratigraphic sequence since the Paleozoic period, to obtain resource evaluation parameters, and to realize the strategic discovery and achieve breakthrough in oil and gas exploration understanding. 展开更多
关键词 South Yellow Sea Basin Meso-Paleozoic Exploration STATUS Research STATUS of oil and gas PROSPECTIVE PREDICTION
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Wave parameters retrieval for dual-polarization C-band synthetic aperture radar using a theoretical-based algorithm under cyclonic conditions 被引量:3
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作者 Yingying Ding Juncheng Zuo +5 位作者 Weizeng Shao jian shi Xinzhe Yuan jian Sun Jiachen Hu Xiaofeng Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第5期21-31,共11页
Theoretical-based ocean wave retrieval algorithms are applied by inverting a synthetic aperture radar(SAR)intensity spectrum into a wave spectrum, that has been developed based on a SAR wave mapping mechanism. In our ... Theoretical-based ocean wave retrieval algorithms are applied by inverting a synthetic aperture radar(SAR)intensity spectrum into a wave spectrum, that has been developed based on a SAR wave mapping mechanism. In our previous studies, it was shown that the wave retrieval algorithm, named the parameterized first-guess spectrum method(PFSM), works for C-band and X-band SAR at low to moderate sea states. In this work, we investigate the performance of the PFSM algorithm when it is applied for dual-polarization c-band sentinel-1(S-1) SAR acquired in extra wide-swath(EW) and interferometric wide-swath(IW) mode under cyclonic conditions.Strong winds are retrieved from six vertical-horizontal(VH) polarization S-1 SAR images using the c-band crosspolarization coupled-parameters ocean(C-3 PO) model and then wave parameters are obtained from the image at the vertical-vertical(VV) polarization channel. significant wave height(SWH) and mean wave period(MWP) are compared with simulations from the WAVEWATCH-III(WW3) model. The validation shows a 0.69 m root mean square error(RMSE) of SWH with a –0.01 m bias and a 0.62 s RMSE of MWP with a –0.17 s bias. Although the PFSM algorithm relies on a good quality SAR spectrum, this study confirms the applicability for wave retrieval from an S-1 SAR image. Moreover, it is found that the retrieved results have less accuracy on the right sector of cyclone eyes where swell directly affects strong wind-sea, while the PFSM algorithm works well on the left and rear sectors of cyclone eyes where the interaction of wind-sea and swell is relatively poor. 展开更多
关键词 WAVE parameters synthetic APERTURE radar cyclonic condition
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The association between retinal vasculature changes and stroke:a literature review and Meta-analysis 被引量:4
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作者 Hui-Qun Wu Huan Wu +7 位作者 Li-Li shi Li-Yuan Yu Li-Yuan Wang Ya-Lan Chen Jin-Song Geng jian shi Kui jiang jian-Cheng Dong 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第1期109-114,共6页
AIM: To determine the association between retinal vasculature changes and stroke.METHODS: MEDLINE and EMBASE were searched for relevant human studies to September 2015 that investigated the association between retin... AIM: To determine the association between retinal vasculature changes and stroke.METHODS: MEDLINE and EMBASE were searched for relevant human studies to September 2015 that investigated the association between retinal vasculature changes and the prevalence or incidence of stroke; the studies were independently examined for their qualities. Data on clinical characteristics and calculated summary odds ratios (ORs) were extracted for associations between retinal microvascular abnormalities and stroke, including stroke subtypes where possible, and adjusted for key variables. RESULTS: Nine cases were included in the study comprising 20 659 patients, 1178 of whom were stroke patients. The retinal microvascular morphological markers used were hemorrhage, microaneurysm, vessel caliber, arteriovenous nicking, and fractal dimension. OR of retinal arteriole narrowing and retinal arteriovenous nicking and stroke was 1.42 and 1.91, respectively, indicating that a small-caliber retinal arteriole and retinal arteriovenous nicking were associated with stroke. OR of retinal hemorrhage and retinal microaneurysm and stroke was 3.21 and 3.83, respectively, indicating that retinal microvascular lesions were highly associated with stroke. Results also showed that retinal fractal dimension reduction was associated with stroke (OR: 2.28 for arteriole network, OR: 1.80 for venular network).CONCLUSION: Retinal vasculature changes have a specific relationship to stroke, which is promising evidence for the prediction of stroke using computerized retinal vessel analysis. 展开更多
关键词 retinal image VASCULATURE STROKE META-ANALYSIS
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Numerical simulation and experimental validation on fabrication of nickel-based superalloy Kagome lattice sandwich structures 被引量:3
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作者 Yan-peng Wei Bo Yu +5 位作者 Quan-zhan Yang Peng Gao jian shi Zhi-quan Miao Jing-chang Cheng Xun Sun 《China Foundry》 SCIE 2020年第1期21-28,共8页
Nickel-based superalloy lattice sandwich structures present higher stiffness,higher strength and higher temperature resistance in comparison with other metals.In this study,the Kagome unit was adopted to design the la... Nickel-based superalloy lattice sandwich structures present higher stiffness,higher strength and higher temperature resistance in comparison with other metals.In this study,the Kagome unit was adopted to design the lattice sandwich structure and ProCAST software was used to simulate the filling and solidification processes of the nickel-based superalloy.Grain morphology and sizes of the nickel-based superalloy lattice sandwich structures were simulated by using of cellular automaton coupled with finite element model(CAFE),and indirect additive manufacture combining with investment casting were carried out to fabricate the nickel-based superalloy lattice sandwich structures.The calculated grain morphology and sizes are in good agreement with the experimental results.The grains are mainly equiaxed with an average size of about 500µm.The simulated results also show that the superheat of melting and the mold preheated temperature have significant influence on the grain size of the Kagome lattice sandwich structures,lower superheat of melting and mold preheated temperatures are encouraged to obtain the fine grains while assuring the integrity of the Kagome lattice sandwich structures for industrial application. 展开更多
关键词 Kagome unit cell lattice structure FABRICATION grain morphology and size CAFE model
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The Clinical Study of a New Management Model Using Mobile Health for Senile Hypertension 被引量:2
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作者 jian shi Ping Wang Aimin Wang 《Health》 2019年第8期1087-1094,共8页
Objective: To evaluate a new management model using mobile health for senile hypertension. Methods: This medical service combined traditional medical treatment with Mobile Health. We use it to explore a new and effect... Objective: To evaluate a new management model using mobile health for senile hypertension. Methods: This medical service combined traditional medical treatment with Mobile Health. We use it to explore a new and effective model of elderly hypertension management and the most effective and lowest cost management crowd. According to the randomized controlled design of trial, 105 old hypertensive patients participated in the study voluntarily in the Qingdao Municipal Hospital were randomly divided into the experimental group (75 cases) and control group (30 cases). Experimental group is divided into geriatric specialist group (25 cases), general practitioner group (25 cases) and nurse group (25 cases). Blood pressure was administered in experimental (with the new model) and control groups (with the traditional model) for 2 months to compare their blood pressure and the decrease of them. Results: Blood pressure was compared between the two groups before and after administration. The systolic blood pressure (SBP) of experimental group is 162.44 ± 13.970 mmHg before administration. SBP of experimental group is 147.69 ± 13.509 mmHg after administration, the difference is statistically significant (P = 0.000). The diastolic blood pressure (DBP) of experimental group is 91.58 ± 10.822 mmHg before administration. DBP of experimental group is 84.64 ± 10.412 mmHg after administration, P = 0.003. SBP of control group is 159.93 ± 15.238 mmHg before administration. The systolic blood pressure of control group is 152.33 ± 14.115 (mmHg) after administration. P is 0.167 (P > 0.05). The difference was not statistically significant. DBP of control group is 94.73 ± 12.401 (mmHg) before administration. DBP of control group is 90.60 ± 11.115 (mmHg) after administration. P is 0.345 (P > 0.05). The difference was not statistically significant. The decrease of SBP of geriatric specialist group, general practitioner group and nurse group is 18.40 ± 11.764 mmHg, 14.47 ± 9.44 mmHg, 10.80 ± 6.026 mmHg. The difference was not statistically significant (P > 0.05). The decrease of DBP of geriatric specialist group, general practitioner group and nurse group is 9.33 ± 7.451 mmHg vs. 5.33 ± 6.287 mmHg vs. 6.13 ± 5.069 mmHg (P > 0.05). Conclusion: The new model is effective and it works well for controlling blood pressure of elderly hypertensive patients. Especially with the doctors and patients’ families, the management effect has been obviously improved. Medical interventions make the new model more scientific. The management of geriatric specialists, general practitioners and nurses is equally valid. 展开更多
关键词 SENILE HYPERTENSION MANAGEMENT MODEL MOBILE HEALTH
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The impact of rain to observed signal from Chinese Gaofen-3 synthetic aperture radar in typhoons 被引量:1
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作者 jian shi Jiachen Hu +4 位作者 Weizeng Shao Xiaoqing Wang Xinzhe Yuan Liangbo Zhao Xiaofeng Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第11期121-133,共13页
Gaofen-3(GF-3),a Chinese civil synthetic aperture radar(SAR)at C-band,has operated since August 2016.Remarkably,several typhoons have been captured by GF-3 around the China Seas over its last two-year mission.In this ... Gaofen-3(GF-3),a Chinese civil synthetic aperture radar(SAR)at C-band,has operated since August 2016.Remarkably,several typhoons have been captured by GF-3 around the China Seas over its last two-year mission.In this study,six images acquired in Global Observation(GLO)and Wide ScanSAR(WSC)modes at verticalvertical(VV)polarization channel are discussed.This work focuses on investigating the observation of rainfall using GF-3 SAR.These images were collocated with winds from the European Centre for Medium-Range Weather Forecasts(ECMWF),significant wave height simulated from the WAVEWATCH-III(WW3)model,sea surface currents from climate forecast system version 2(CFSv2)of the National Centers for Environmental Prediction(NCEP)and rain rate data from the Tropical Rainfall Measuring Mission(TRMM)satellite.Sea surface roughness,was compared with the normalized radar cross section(NRCS)from SAR observations,and indicated a 0.8 correlation(COR).We analyzed the dependences of the difference between model-simulated NRCS and SARmeasured NRCS on the TRMM rain rate and WW3-simulated significant wave height.It was found that the effects of rain on SAR damps the radar signal at incidence angles ranging from 15°to 30°,while it enhances the radar signal at incidence angles ranging from 30°to 45°and incidence angles smaller than 10°.This behavior is consistent with previous studies and an algorithm for rain rate retrieval is anticipated for GF-3 SAR. 展开更多
关键词 Gaofen-3 synthetic APERTURE radar TYPHOON
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Compression behavior of 316L lattice structures produced by indirect additive manufacturing 被引量:1
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作者 Yan-peng Wei Hao Yang +4 位作者 Jing-chang Cheng Peng Gao jian shi Feng Lin Bo Yu 《China Foundry》 SCIE CAS CSCD 2023年第2期83-88,共6页
As a new type of lightweight structure,metallic lattice structure has higher stiffness and strength to weight ratio.To freely obtain 316L lattice structures with designed cell structure and adjustable porosity,additiv... As a new type of lightweight structure,metallic lattice structure has higher stiffness and strength to weight ratio.To freely obtain 316L lattice structures with designed cell structure and adjustable porosity,additive manufacturing combined with investment casting was conducted to fabricate the 316L lattice structures with Kelvin cell.The compression simulation of 316L lattice structures with different porosities was carried out by using the finite element method.The numerical simulation results were verified by compression experiment,and the simulated results were consistent with the compression tests.The compressive mechanical properties of 316L lattice structures are directly related to porosity and independent of strut diameters.The 316L lattice structures with Kelvin cell have a smooth stress-strain curve and obvious plastic platform,and the hump stress-strain curves are avoided. 展开更多
关键词 316L lattice structures indirect additive manufacturing compression behavior investment casting finite element simulation
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Application of traditional indexes and adverse events in the ophthalmologic perioperative medical quality evaluation during 2010-2012 被引量:1
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作者 Yong-Na Bian jian shi +2 位作者 Jun-Jun She Jie Wu jian-Min Gao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第5期1051-1055,共5页
AIM: To evaluate the medical quality of ophthalmologic perioperative period during 2010-2012 in our hospital. METHODS: The relevant data of perioperative period were collected in our hospital during 2010-2012, and the... AIM: To evaluate the medical quality of ophthalmologic perioperative period during 2010-2012 in our hospital. METHODS: The relevant data of perioperative period were collected in our hospital during 2010-2012, and the medical quality of perioperative period was evaluated by using the traditional evaluation indexes and adverse events. Whereby, the traditional indicators include vision changes, improving of intraocular pressure, diagnostic accordance rate before and after operation, cure improvement rate, successful rescue rate, and incidence of surgical complications, etc Adverse events are associated with ophthalmologic perioperative events including pressure sores, postoperative wound infection, drug adverse events, and equipment related adverse events. RESULTS: There were 1483, 1662 and 1931 ophthalmic operations in our hospital in the year 2010, 2011 and 2012, respectively. From traditional index analysis, the proportions of vision improvement for each year were 96.43%, 96.76% and 97.32%, respectively; the rates of intraocular pressure improvement were 87.50%, 85.72% and 90.17%, respectively ( P <0.05); the diagnostic accordance rates before and after operation were 99.86%, 99.94% and 99.90%, respectively; cure improvement rates were 99.73%, 99.93% and 99.84%, respectively; the successful rescue rates were 82.98%, 81.46% and 76.66%, respectively; the complications incidence rates were 18.44%, 17.52% and 17.97%, respectively. The negative factor analysis results showed that: among all the patients of ophthalmic surgeries in our hospital during 2010 and 2012, only one case of postoperative wound infection was found in 2011, and also only one case of tumbling in 2010. The adverse drug events for each year were 1 case (0.07%), 2 cases (0.12%), and 4 cases (0.21%), respectively; the medical device adverse events for each year were 3 cases (0.20%), 5 cases (0.30%), and 6 cases (0.31%), respectively. Noticeably, only one case with postoperative infection of endophthalmitis was found in 2011. Moreover, no pulmonary infection or pulmonary embolism occurred during the three years. The perioperative adverse event rates for each year were 0.34% (5/1483), 0.48% (8/1662) and 0.52% (10/1931), respectively. Though incidence was rising during the three years, no statistical significance was observed (P>0.05). It is the same case with drugs and medical devices adverse events (P>0.05). CONCLUSION: Traditional indicators reflect an excellent operation of the perioperative ophthalmologic quality, whereas adverse events analysis indicates some underlying problems. Compared with the traditional indexes for medical quality evaluation, the index of adverse events is more reasonable and easier to make an objective evaluation for medical quality of ophthalmologic perioperation, facilitating further refine analysis. Reasonable application of the adverse events indicators helps hospital to make the detailed quality control measures. 展开更多
关键词 perioperative period medical quality evaluation index adverse events OPHTHALMOLOGY
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