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ICS愿与中国加强合作 促全球航运界齐心抗疫 被引量:1
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作者 刘洋 《中国远洋海运》 2020年第3期45-45,共1页
中国航运界抗疫情、保复工,全力保障全球供应链平稳运行的行动也赢得了国际同业的赞誉与支持。以ICS、BIMCO等为代表的全球行业组织及国际港航企业纷纷表示要与中国业界携手战"疫"、共克时艰。目前新冠肺炎疫情在中国已经得... 中国航运界抗疫情、保复工,全力保障全球供应链平稳运行的行动也赢得了国际同业的赞誉与支持。以ICS、BIMCO等为代表的全球行业组织及国际港航企业纷纷表示要与中国业界携手战"疫"、共克时艰。目前新冠肺炎疫情在中国已经得到有效控制。但韩国、日本、伊朗、意大利乃至美国等国家确诊病例大幅激增,着实令人担忧。根据国际航运公会(ICS)的统计数据,新冠疫情致使航运业每周损失约3.5亿美元,世界集装箱贸易量减少35万箱。此外,全球供应链也受到影响,船舶在港口的检疫带来挑战。这些因为疫情导致的困难,也促使全球航运界更加齐心抗疫的决心。 展开更多
关键词 中国船东协会 全球供应链 国际航运业 ICS
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On Accurate Detection of Oceanic Features from Satellite IR Data Using ICSED Method
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作者 李俊 周风仙 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期373-382,共10页
ICSED (Improved Cluster Shade Edge Detection) algorithm and other various methods to accurately and efficiently detect edges on satellite data are presented. Error rate criterion is used to statistically evaluate the ... ICSED (Improved Cluster Shade Edge Detection) algorithm and other various methods to accurately and efficiently detect edges on satellite data are presented. Error rate criterion is used to statistically evaluate the performances of these methods in detecting oceanic features for both noise free and noise contaminated AVHRR (Advanced Very High Resolution Radiometer) IR image with Kuroshio. Also, practical experiments in detecting the eddy of Kuroshio with these methods are carried out for comparison. Results show that the ICSED algorithm has more advantages than other methods in detecting mesoscale features of ocean. Finally, the effectiveness of window size of ICSED method to oceanic features detection is quantitatively discussed. 展开更多
关键词 On Accurate Detection of Oceanic Features from Satellite IR Data Using ICSED Method IR
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与中国在全球航运事务上“和合共生,交融并进”——专访国际航运公会(ICS)中国办事处首席代表刘洋
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作者 木淼 刘洋 《中国远洋海运》 2020年第12期52-55,共4页
关键提示为了保障海上贸易的正常运转,ICS协调整个行业对新冠疫情做出统一反应,并迅速制定针对船舶经营者的综合指南和提交给政府的详细建议。在面对船员换班困境时,ICS中国办事处始终与中国相关主管部门和行业协会保持沟通与联系,确保... 关键提示为了保障海上贸易的正常运转,ICS协调整个行业对新冠疫情做出统一反应,并迅速制定针对船舶经营者的综合指南和提交给政府的详细建议。在面对船员换班困境时,ICS中国办事处始终与中国相关主管部门和行业协会保持沟通与联系,确保将国际航运业第一手的资料和讯息及时传递给他们,并将中国关于避免船上人员感染和港口应对疫情的相关政策措施及时通报给ICS会员。 展开更多
关键词 国际航运业 海上贸易 全球航运 行业协会 刘洋 和合共生 政策措施 ICS
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Clinical Characteristics and Outcomes of Severe or Critical COVID-19 Patients Presenting No Respiratory Symptoms or Fever at Onset
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作者 Juanjuan Xu Zhengrong Yin +7 位作者 Yu Liu Sufei Wang Limin Duan Yi An Jinshuo Fan Tingting Liao Yang Jin Jianguo Chen 《Engineering》 SCIE EI 2021年第10期1452-1458,共7页
It is difficult to identify suspected cases of atypical patients with coronavirus disease 2019(COVID-19),and data on severe or critical patients are scanty.This retrospective study presents the clinical,laboratory,and... It is difficult to identify suspected cases of atypical patients with coronavirus disease 2019(COVID-19),and data on severe or critical patients are scanty.This retrospective study presents the clinical,laboratory,and radiological profiles,treatments,and outcomes of atypical COVID-19 patients without respiratory symptoms or fever at onset.The study examined ten atypical patients out of 909 severe or critical patients diagnosed with COVID-19 in Wuhan Union Hospital West Campus between 25 January 2020 and 10 February 2020.Data were obtained from the electronic medical records of severe or critical patients without respiratory symptoms or fever at onset.Outcomes were followed up to discharge or death.Among 943 COVID-19 patients,909(96.4%)were severe or critical type.Of the severe or critical patients,ten(1.1%)presented without respiratory symptoms or fever at admission.The median age of the ten participants was 63 years(interquartile range(IQR):57–72),and seven participants were men.The median time from symptom onset to admission was 14 d(IQR:7–20).Eight of the ten patients had chronic diseases.The patients had fatigue(n=5),headache or dizziness(n=4),diarrhea(n=5),anorexia(n=3),nausea or vomiting(n=3),and eye discomfort(n=1).Four patients were found to have lymphopenia.Imaging examination revealed that nine patients had bilateral pneumonia and one had unilateral pneumonia.Eventually,two patients died and eight were discharged.In the discharged patients,the median time from admission to discharge lasted 24 d(IQR:13–43).In summary,some severe or critical COVID-19 patients were found to have no respiratory symptoms or fever at onset.All such atypical cases should be identified and quarantined as early as possible,since they tend to have a prolonged hospital stay or fatal outcomes.Chest computed tomography(CT)scan and nucleic acid detection should be performed immediately on close contacts of COVID-19 patients to screen out those with atypical infections,even if the contacts present without respiratory symptoms or fever at onset. 展开更多
关键词 SARS-CoV-2 COVID-19 Atypical clinical characteristics
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Analysis of Atmospheric Boundary Layer Height Characteristics over the Arctic Ocean Using the Aircraft and GPS Soundings 被引量:13
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作者 DAI Cheng-Ying GAO Zhi-Qiu +1 位作者 WANG Qing CHENG Gang 《Atmospheric and Oceanic Science Letters》 2011年第2期124-130,共7页
Utilizing aircraft sounding data collected from the Surface Heat Budget of the Arctic Ocean (SHEBA, 1998) campaign, the authors evaluated commonly-used profile methods for Arctic ABL height estimation by validating ag... Utilizing aircraft sounding data collected from the Surface Heat Budget of the Arctic Ocean (SHEBA, 1998) campaign, the authors evaluated commonly-used profile methods for Arctic ABL height estimation by validating against the'true'ABL height from aircraft sounding profiles, where ABL height is defined as the top of the layer with significant turbulence. Furthermore, the best performing method was used to estimate ABL height from the one-year GPS soundings obtained during SHEBA (October 1997-October 1998). It was found that the temperature gradient method produces a reliable estimate of ABL height. Additionally, the authors determined optimal threshold values of temperature gradient for stable boundary layer (SBL) and convective boundary layer (CBL) to be 6.5 K/100 m and 1.0 K/100 m, respectively. The maximum ABL height during the year was 1150 m occurred in May. Median values of Arctic ABL height in May, June, July, and August were 400 m, 430 m, 180 m, and 320 m, respectively. Arctic ABL heights are clearly higher in the spring than in the summer. 展开更多
关键词 aircraft sounding Arctic boundary layer boundary layer height GPS sounding turbulence
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The Microwave Characteristics of an In_(0.4)Ga_(0.6)As Metal-Oxide-Semiconductor Field-Effect Transistor with an In_(0.49)Ga_(0.51)P Interfacial Layer
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作者 LIU Gui-Ming CHANG Hu-Dong +1 位作者 SUN Bing LIU Hong-Gang 《Chinese Physics Letters》 SCIE CAS CSCD 2013年第8期160-163,共4页
A high microwave performance enhancement-mode(E-mode)In_(0.4)Ga_(0.6)As channel metal-oxide-semiconductor field-effect transistor(MOSFET)with a Si-doped In_(0.49)Ga0.51P interfacial layer is fabricated.A 0.8-μm-gate-... A high microwave performance enhancement-mode(E-mode)In_(0.4)Ga_(0.6)As channel metal-oxide-semiconductor field-effect transistor(MOSFET)with a Si-doped In_(0.49)Ga0.51P interfacial layer is fabricated.A 0.8-μm-gate-length In_(0.4)Ga_(0.6)As MOSFET with a 5-nm Al_(2)O_(3) dielectric layer provides a current gain cutoff frequency of 16.7 GHz and a maximum oscillation frequency of 52 GHz.A semi-empirical small-signal-parameter extraction technique accounting for the low frequency anomaly of this MOSFET device is described,which is based on on-wafer S-parameter measurements.Excellent agreement between measured and simulated scattering parameters as well as the physically realistic circuit elements demonstrates the validity of this approach. 展开更多
关键词 SCATTERING TRANSISTOR PARAMETER
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第11届东方脑血管病介入治疗大会(OCIN)暨第8届国际脑血管病论坛及世界颅内支架大会(ICS)、第6届东亚神经介入治疗大会(EACoN)会议通知
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《临床神经外科杂志》 CAS 2011年第2期90-90,共1页
本次大会由第二军医大学附属长海医院临床神经医学中心、神经外科承办,将于2011年9月8日~11日在中国上海隆重召开。
关键词 神经介入治疗 脑血管病 颅内支架 第二军医大学附属长海医院 世界 论坛 国际 东方
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Fast and Accurate Machine Learning Inverse Lithography Using Physics Based Feature Maps and Specially Designed DCNN
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作者 Xuelong Shi Yan Yan +4 位作者 Tao Zhou Xueru Yu Chen Li Shoumian Chen Yuhang Zhao 《Journal of Microelectronic Manufacturing》 2020年第4期51-58,共8页
Inverse lithography technology(ILT)is intended to achieve optimal mask design to print a lithography target for a given lithography process.Full chip implementation of rigorous inverse lithography remains a challengin... Inverse lithography technology(ILT)is intended to achieve optimal mask design to print a lithography target for a given lithography process.Full chip implementation of rigorous inverse lithography remains a challenging task because of enormous computational resource requirements and long computational time.To achieve full chip ILT solution,attempts have been made by using machine learning techniques based on deep convolution neural network(DCNN).The reported input for such DCNN is the rasterized images of the lithography target;such pure geometrical input requires DCNN to possess considerable number of layers to learn the optical properties of the mask,the nonlinear imaging process,and the rigorous ILT algorithm as well.To alleviate the difficulties,we have proposed the physics based optimal feature vector design for machine learning ILT in our early report.Although physics based feature vector followed by feedforward neural network can provide the solution to machine learning ILT,the feature vector is long and it can consume considerable amount of memory resource in practical implementation.To improve the resource efficiency,we proposed a hybrid approach in this study by combining first few physics based feature maps with a specially designed DCNN structure to learn the rigorous ILT algorithm.Our results show that this approach can make machine learning ILT easy,fast and more accurate. 展开更多
关键词 Optimal feature maps inverse lithography technology(ILT) deep convolution neural network(DCNN).
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Quantum weak force sensing with squeezed magnomechanics
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作者 Qian Zhang Jie Wang +3 位作者 Tian-Xiang Lu Ran Huang Franco Nori Hui Jing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第10期23-32,共10页
Cavity magnomechanics,exhibiting remarkable experimental tunability,rich magnonic nonlinearities,and compatibility with various quantum systems,has witnessed considerable advances in recent years.However,the potential... Cavity magnomechanics,exhibiting remarkable experimental tunability,rich magnonic nonlinearities,and compatibility with various quantum systems,has witnessed considerable advances in recent years.However,the potential benefits of using cavity magnomechanical(CMM)systems in further improving the performance of quantum-enhanced sensing for weak forces remain largely unexplored.Here we show that,by squeezing the magnons,the performance of a quantum CMM sensor can be significantly enhanced beyond the standard quantum limit(SQL).We find that,for comparable parameters,two orders of magnitude enhancement in the force sensitivity can be achieved in comparison with the case without magnon squeezing.Moreover,we obtain the optimal parameter regimes of homodyne angle for minimizing the added quantum noise.Our findings provide a promising approach for highly tunable and compatible quantum force sensing using hybrid CMM devices,with potential applications ranging from quantum precision measurements to quantum information processing. 展开更多
关键词 quantum force sensing cavity magnomechanics magnon Kerr effect
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Robust Optimal Framework for Doubly Fed Induction Generator with Uncertain Dynamics
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作者 Yongfeng Lü Xiaowei Zhao Priyank Shah 《Protection and Control of Modern Power Systems》 SCIE EI 2024年第5期129-141,共13页
A robust optimal framework is designed herein to mitigate the oscillatory dynamics in a doubly fed induction generator(DFIG)even in the presence of network disturbances and input variation.To address uncertain dynamic... A robust optimal framework is designed herein to mitigate the oscillatory dynamics in a doubly fed induction generator(DFIG)even in the presence of network disturbances and input variation.To address uncertain dynamics,herein,a novel transformation formula is developed for a wind energy conversion system.An unscented Kalman filter is applied to estimate the un-measured internal states of the wind energy conversion system using terminal measurements.The detailed convergence and stability analyses of the presented framework are investigated to validate its effectiveness.Additionally,comparative modal analyses are carried out to demonstrate the improvement in the damping of critical low-frequency oscillatory modes using the presented framework.The simulation results demonstrate satisfactory performance under various operating scenarios,such as increasing and decreasing wind speed and varying the terminal voltage.The comparative performance is demonstrated to validate the effectiveness of the presented framework over that of the state-of-the-art frameworks.Index Terms—Optimal control,power system,renew-able energy sources,wind energy conversion system,doubly fed induction generator. 展开更多
关键词 Optimal control power system renew-able energy sources wind energy conversion system doubly fed induction generator
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The clinical,radiological,and surgical characteristics of anterior perforated substance glioma:a retrospective study
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作者 Zhiliang Wang Lianwang Li +2 位作者 Zheng Wang Xuzhu Chen Zhong Zhang 《Chinese Neurosurgical Journal》 CAS CSCD 2024年第1期28-34,共7页
Background To explore the clinical,radiological,and surgical characteristics of anterior perforated substance(APS)gliomas.Methods Twenty patients with APS glioma who were treated with surgery between March 2019 and Ja... Background To explore the clinical,radiological,and surgical characteristics of anterior perforated substance(APS)gliomas.Methods Twenty patients with APS glioma who were treated with surgery between March 2019 and January 2022 from Tiantan hospital were retrospectively reviewed.The clinical,histological and radiological data were collected.Results Twenty patients,including 7 males(55%)and 13 females(45%),with a mean age at diagnosis of 37.9 years(range,28-53 years)underwent operative intervention for APS.Headaches and dizziness were the most common preoperative symptoms in the majority patients(14,70%).Based on radiological features of MRI,the APS was classified into two subtypes,type A and type B.Seven patients(40%)in type A indicated a clear tumor margin,while 13 patients(60%)in type B showed an ill-defined margin.The surgical approach including frontal,temporal,and coronal frontal incisions for type A and type B tumors,respectively.Three patients in type A received total resection,while one patient in type B were total resected.Pathologically,12 cases(60%,12/20)were diagnosed as astrocytoma and 8 cases(20%,8/20)were oligodendroglioma.Meanwhile,17 cases(85%,17/20)had MGMT promotor methylation.Conclusion In this study,we performed the first systematic research of patients with APS glioma.Most of patients with APS presented headaches and dizziness symptoms.The APS glioma was further divided into two major radiological subtypes with relevant different surgical approaches.The APS glioma in type A were more likely to receive total resection. 展开更多
关键词 Anterior perforated substance GLIOMA Magnetic resonance imaging Operation
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Topical ocular administration of DPP-Ⅳ inhibitors:a new approach for treating diabetes-induced retinal neurodegeneration 被引量:1
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作者 Rafael Simó Cristina Hernández 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期713-714,共2页
Retinal neurodegeneration plays a significant role in the pathogenesis of diabetic retinopathy(DR),the leading cause of preventable blindness.In fact,the American Diabetes Association has defined DR as a highly specif... Retinal neurodegeneration plays a significant role in the pathogenesis of diabetic retinopathy(DR),the leading cause of preventable blindness.In fact,the American Diabetes Association has defined DR as a highly specific neurovascular complication(Solomon et al.,2017).Therefore,it is no longer acceptable to consider DR as merely a microvascular complication.In this regard,the term diabetic retinal disease(DRD)has been proposed as a broader term comprising microangiopathy and neurodegeneration.However,there are currently no treatments available that directly target the neurodegenerative changes of DR.This paper will give new insights into the translational research in this field with particular emphasis on glucagon-like peptide 1/dipeptidyl peptidase IV(GLP-1/DPP-IV)inhibitors. 展开更多
关键词 NEURODEGENERATION OCULAR INSIGHT
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Vibration-reduced anxiety-like behavior relies on ameliorating abnormalities of the somatosensory cortex and medial prefrontal cortex 被引量:1
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作者 Afzal Misrani Sidra Tabassum +8 位作者 Tintin Wang Huixian Huang Jinxiang Jiang Hongjun Diao Yanping Zhao Zhen Huang Shaohua Tan Cheng Long Li Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1351-1359,共9页
Tibetan singing bowls emit low-frequency sounds and produce perceptible harmonic tones and vibrations through manual tapping.The sounds the singing bowls produce have been shown to enhance relaxation and reduce anxiet... Tibetan singing bowls emit low-frequency sounds and produce perceptible harmonic tones and vibrations through manual tapping.The sounds the singing bowls produce have been shown to enhance relaxation and reduce anxiety.However,the underlying mechanism remains unclear.In this study,we used chronic restraint stress or sleep deprivation to establish mouse models of anxiety that exhibit anxiety-like behaviors.We then supplied treatment with singing bowls in a bottomless cage placed on the top of a cushion.We found that unlike in humans,the combination of harmonic tones and vibrations did not improve anxietylike behaviors in mice,while individual vibration components did.Additionally,the vibration of singing bowls increased the level of N-methyl-D-aspartate receptor 1 in the somatosensory cortex and prefrontal cortex of the mice,decreased the level ofγ-aminobutyric acid A(GABA)receptorα1 subtype,reduced the level of CaMKII in the prefrontal cortex,and increased the number of GABAergic interneurons.At the same time,electrophysiological tests showed that the vibration of singing bowls significantly reduced the abnormal low-frequency gamma oscillation peak frequency in the medial prefrontal cortex caused by stress restraint pressure and sleep deprivation.Results from this study indicate that the vibration of singing bowls can alleviate anxiety-like behaviors by reducing abnormal molecular and electrophysiological events in somatosensory and medial prefrontal cortex. 展开更多
关键词 anxiety medial prefrontal cortex parvalbumin interneuron pressure somatosensory cortex Tibetan singing bowl VIBRATION
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Molecular dynamics simulations of initial Pd and PdO nanocluster growth in a magnetron gas aggregation source 被引量:1
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作者 Pascal Brault William Chamorro-Coral +5 位作者 Sotheara Chuon Amael Caillard Jean-Marc Bauchire Stevè Baranton Christophe Coutanceau Erik Neyts 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2019年第2期324-329,共6页
Molecular dynamics simulations are carried out for describing growth of Pd and PdO nanoclusters using the ReaxFF force field. The resulting nanocluster structures are successfully compared to those of nanoclusters exp... Molecular dynamics simulations are carried out for describing growth of Pd and PdO nanoclusters using the ReaxFF force field. The resulting nanocluster structures are successfully compared to those of nanoclusters experimentally grown in a gas aggregation source. The PdO structure is quasi-crystalline as revealed by high resolution transmission microscope analysis for experimental PdO nanoclusters. The role of the nanocluster temperature in the molecular dynamics simulated growth is highlighted. 展开更多
关键词 molecular dynamics cluster growth plasma SPUTTERING NANOCATALYST
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Combinative approach of transzonular triamcinolonemoxifloxacin and perioperative drops to minimize postoperative complications of cataract surgery
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作者 Behnam Rabiee Muhamad Festok +5 位作者 Michael Gaspari Abid Haseeb Aaila Chaudhry Layla Kamoun Imtiaz Chaudhry Iftikhar Chaudhry 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期845-851,共7页
AIM: To investigate the effectiveness of combinationtherapy with transzonular triamcinolone-moxifloxacin andconventional perioperative drops in reducing postoperativecomplications of cataract surgery. METHODS: Electro... AIM: To investigate the effectiveness of combinationtherapy with transzonular triamcinolone-moxifloxacin andconventional perioperative drops in reducing postoperativecomplications of cataract surgery. METHODS: Electronic medical records of cataractsurgery patients (single surgeon) were reviewed fromJanuary 2018 to September 2021. The rate of postoperativecomplications including prolonged and/or recurrentpostoperative inflammation, endophthalmitis, cystoid macularedema (CME), and intraocular pressure (IOP) was comparedbetween the patients receiving combinative therapy andpatients receiving drops only. RESULTS: Totally 596 patients and 1057 eyes(Combinative-Therapy group 493 and Drop-Only group 564)were included in this study. Using combination therapyreduced the relative risk of postoperative inflammationby 26.9% (16.6% Combinative-Therapy vs 22.7% Drop-Only, P=0.013). The incidence of endophthalmitis was 0in Combinative-Therapy group vs 0.5% in Drop-Only group(relative risk reduction 100%), although not statisticallysignificant (P=0.10). The incidence of severe IOP spikeswas not significantly different between Combinative-Therapy (2.4%) and Drop-Only (1.6%) groups (P=0.33).The relative risk of postoperative CME was 51.4% less inthree months follow up visit in Combinative-Therapy group,although not statistically significant (P=0.07). The visualoutcome 1-month postop. (best corrected visual acuity) wassignificantly better in Combinative-Therapy (logMAR 0.10)compared to Drop-Only (logMAR 0.14) groups (P=0.02) whilethe baseline visual acuity was not significantly different. CONCLUSION: The combinative approach oftranszonular triamcinolone-moxifloxacin plus perioperativeeyedrops is an effective method to minimize postoperativeinflammation, with better visual outcomes. It couldpotentially reduce the risk of postoperative endophthalmitisand CME (near-significant P-values;larger studies couldanalyze better considering low incidence). 展开更多
关键词 CATARACT ENDOPHTHALMITIS cystoid macular edema postoperative complications transzonular injection
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中国和欧盟精准医疗发展——从概念到实践
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作者 《中国医药导刊》 2024年第1期1-1,共1页
精准医学是针对疾病病因的复杂性,综合考虑个体生物特征、环境、生活方式的个体差异,制定有效健康干预和治疗策略的一种新型医疗模式,是生物技术、信息技术、医学研究的交汇、融合与应用。近年来,全球精准医疗发展迅速,相关技术也在不... 精准医学是针对疾病病因的复杂性,综合考虑个体生物特征、环境、生活方式的个体差异,制定有效健康干预和治疗策略的一种新型医疗模式,是生物技术、信息技术、医学研究的交汇、融合与应用。近年来,全球精准医疗发展迅速,相关技术也在不断成熟。精准医学研究成果走向应用,覆盖从基础研究到临床应用的精准医学研究体系已经基本形成,其科学和社会价值日益凸显,作为战略新兴领域,各国加大布局和支持。 展开更多
关键词 医学研究成果 精准医学 信息技术 精准医疗 融合与应用 健康干预 个体生物 个体差异
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3D Ice Shape Description Method Based on BLSOM Neural Network
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作者 ZHU Bailiu ZUO Chenglin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期70-80,共11页
When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes t... When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes the key task of the icing wind tunnel tests.In the icing wind tunnel test of the tail wing model of a large amphibious aircraft,in order to obtain accurate typical test ice shape,the Romer Absolute Scanner is used to obtain the 3D point cloud data of the ice shape on the tail wing model.Then,the batch-learning self-organizing map(BLSOM)neural network is used to obtain the 2D average ice shape along the model direction based on the 3D point cloud data of the ice shape,while its tolerance band is calculated using the probabilistic statistical method.The results show that the combination of 2D average ice shape and its tolerance band can represent the 3D characteristics of the test ice shape effectively,which can be used as the typical test ice shape for comparative analysis with the calculated ice shape. 展开更多
关键词 icing wind tunnel test ice shape batch-learning self-organizing map neural network 3D point cloud
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Angle-resolved photoemission study of NbGeSb with non-symmorphic symmetry
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作者 马欢 谭宁 +5 位作者 吴徐传 李满 王义炎 路洪艳 夏天龙 王善才 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期464-470,共7页
We investigate the electronic structure of NbGeSb with non-symmorphic symmetry.We employ angle-resolved photoemission spectroscopy(ARPES)to observe and identify the bulk and surface states over the Brillouin zone.By u... We investigate the electronic structure of NbGeSb with non-symmorphic symmetry.We employ angle-resolved photoemission spectroscopy(ARPES)to observe and identify the bulk and surface states over the Brillouin zone.By utilizing high-energy photons,we identify the bulk Fermi surface and bulk nodal line along the direction X–R,while the Fermi surface of the surface state is observed by using low-energy photons.We observe the splitting of surface bands away from the high-symmetry point X.The density functional theory calculations on bulk and 1 to 5-layer slab models,as well as spin textures of NbGeSb,verify that the band splitting could be attributed to the Rashba-like spin–orbit coupling caused by space-inversion-symmetry breaking at the surface.These splitted surface bands cross with each other,forming two-dimensional Weyl-like crossings that are protected by mirror symmetry.Our findings provide insights into the two-dimensional topological and symmetry-protected band inversion of surface states. 展开更多
关键词 non-symmorphic symmetry nodal line splitting of surface bands angle-resolved photoemission spectroscopy
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Diatom and Diatomite: Different Focus on Natural Media to Material Science Path
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作者 Secou Sall Vasiliki Papaefthimiou +7 位作者 Thierry Dintzer Fabrice Vigneron Eric Brendlé Pierre Petit Tom Ferte Saliha Haddoum Sana Labidi Corinne Petit 《American Journal of Analytical Chemistry》 CAS 2024年第1期1-29,共29页
Bio-silica issued from diatom, a microalgae, is attracted increasing attention in material science thanks to its peculiar nanoarchitecture and related properties with versatile applications. The present work is a deep... Bio-silica issued from diatom, a microalgae, is attracted increasing attention in material science thanks to its peculiar nanoarchitecture and related properties with versatile applications. The present work is a deep analysis on morphological and chemical properties of bio-silica issued from fossil origin (diatomaceous earth) and living one (algal paste). An optimization in purification protocol was performed to obtain multiparous bio-silica from its raw media with keeping its original shape entirely. Multiple characterization methods as scanning electronic microscopy (SEM), infrared spectroscopy, x-ray diffraction (DRX), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), nitrogen adsorption and inverse gas chromatography (IGC), were used to check the purification protocol efficiency as well as to gather accurate information on morphology and chemical composition of diatom material obtained in large amount. 展开更多
关键词 DIATOM DIATOMITE Bio-Silica PURIFICATION Frustule
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Nanoscale cathodoluminescence spectroscopy probing the nitride quantum wells in an electron microscope
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作者 刘哲彤 刘秉尧 +8 位作者 梁冬冬 李晓梅 李晓敏 陈莉 朱瑞 徐军 魏同波 白雪冬 高鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期144-149,共6页
To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and ... To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and spectroscopy was used to measure the luminescence of In_(0.15)Ga_(0.85)N five-period multiquantum wells.The lattice-composition-energy relationship was established with the help of energy-dispersive x-ray spectroscopy,and the bandgaps of In_(0.15)Ga_(0.85)N and GaN in multiple quantum wells were extracted by electron energy loss spectroscopy to understand the features of cathodoluminescence spectra.The luminescence differences between different periods of multiquantum wells and the effects of defects such as composition fluctuation and dislocations on the luminescence of multiple quantum wells were revealed.Our study establishing the direct relationship between the atomic structure of In_(x)Ga_(1-x)N multiquantum wells and photoelectric properties provides useful information for nitride applications. 展开更多
关键词 nitride multiquantum wells defect CATHODOLUMINESCENCE scanning transmission electron microscopy
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