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Acute zonal occult outer retinopathy complex and angioid streaks:a case report
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作者 Zhen-Yu Liu Hang Zhang +1 位作者 Xiu-Li Sun Xiao-Yan Peng 《International Journal of Ophthalmology(English edition)》 2026年第1期193-196,共4页
Dear Editor,We present a case of acute zonal occult outer retinopathy(AZOOR)complex in a myopic patient with angioid streaks(ASs).A 19-year-old female has been experiencing visual field defects in her left eye for mor... Dear Editor,We present a case of acute zonal occult outer retinopathy(AZOOR)complex in a myopic patient with angioid streaks(ASs).A 19-year-old female has been experiencing visual field defects in her left eye for more than 3y.She was diagnosed with ASs and choroiditis at a local hospital.She has a seven-year history of bilateral high myopia.A fundus examination confirmed the presence of ASs and myopic fundus changes in both eyes.Multimodal imaging revealed an AZOOR complex in the left eye. 展开更多
关键词 myopic fundus changes zonal occult outer retinopathy azoor complex Angioid Streaks Acute Zonal Occult outer Retinopathy MYOPIA fundus examination angioid streaks ass azoor complex
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Source process of the 2021 M_(W)6.6 outer rise earthquake off the west coast of northern Sumatra
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作者 Bagus Adi Wibowo Hongru Li +5 位作者 Anisa Nurbaeti Rahayu Ling Bai Supriyanto Rohadi Putu Hendra Widyadharma Abraham Arimuko Suko Prayitno Adi 《地球与行星物理论评(中英文)》 2026年第1期51-61,共11页
The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer r... The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer rise earthquakes have been observed along the Sunda arc,following the estimated rupture area of the 2005 M_(W)8.6 Nias earthquakes.Here,we used kinematic waveform inversion(KIWI)to obtain the source parameters of the 14 May 2021 M_(W)6.6 event off the west coast of northern Sumatra and to define the fault plane that triggered this outer rise event.The KIWI algorithm allows two types of seismic source to be configured:the moment tensor model to describe the type of shear with six moment tensor components and the Eikonal model for the rupture of pure double-couple sources.This method was chosen for its flexibility to be applied for different sources of seismicity and also for the automated full-moment tensor solution with real-time monitoring.We used full waveform traces from 8 broadband seismic stations within 1000 km epicentral distances sourced from the Incorporated Research Institutions for Seismology(IRIS-IDA)and Geofon GFZ seismic record databases.The initial origin time and hypocenter values are obtained from the IRIS-IDA.The synthetic seismograms used in the inversion process are based on the existing regional green function database model and were accessed from the KIWI Tools Green's Function Database.The obtained scalar seismic moment value is 1.18×10^(19)N·m,equivalent to a moment magnitude M_(W)6.6.The source parameters are 140°,44°,and−99°for the strike,dip,and rake values at a centroid depth of 10.2 km,indicating that this event is a normal fault earthquake that occurred in the outer rise area.The outer rise events with normal faults typically occur at the shallow part of the plate,with nodal-plane dips predominantly in the range of 30°-60°on the weak oceanic lithosphere due to hydrothermal alteration.The stress regime around the plate subduction zone varies both temporally and spatially due to the cyclic influences of megathrust earthquakes.Tensional outer rise earthquakes tend to occur after the megathrust events.The relative timing of these events is not known due to the viscous relaxation of the down going slab and poroelastic response in the trench slope region.The occurrence of the 14 May 2021 earthquake shows the seismicity in the outer rise region in the strongly coupled Sunda arc subduction zone due to elastic bending stress within the duration of the seismic cycle. 展开更多
关键词 outer rise earthquake kinematic waveform inversion source process
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Bacteria outer membrane-based oxygen gels alleviate tumor hypoxia for enhanced systemic immune response to radiotherapy
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作者 Deyuan Zheng Junhong Yao +7 位作者 Haiheng Xu Shuqin Xiong Qingsong Ye Yiyun Chen Chuan Zhao Min Zhang Xuehui Rui Jinhui Wu 《Science China Materials》 2026年第3期1729-1740,共12页
Radiotherapy(RT)is considered a standard cancer treatment that directly kills tumor cells and promotes a systemic immune response.However,RT may also lead to tumor hypoxia,which further inhibits the antigen-presenting... Radiotherapy(RT)is considered a standard cancer treatment that directly kills tumor cells and promotes a systemic immune response.However,RT may also lead to tumor hypoxia,which further inhibits the antigen-presenting function of dendritic cells(DCs)and thereby weakens the systemic anti-tumor immune response induced by radiotherapy.In this study,the oxygen-loaded in situ gels carrying bacterial outer membrane(MOGel)were synthesized.As the gels slowly degraded,oxygen was gradually released to alleviate tumor hypoxia.The released bacterial outer membrane(OM)continuously activated DCs,enhancing their antigenpresenting capability.The results demonstrated that MOGel combined with RT induced the strongest tumor cell apoptosis in vitro and achieved a 80%tumor suppression rate in a colon cancer orthotopic model.Importantly,MOGel+RT induced an enhanced abscopal effect,and hypoxia and enhanced DCs activation contributed to the systemic immune response.Thus,OM-based oxygen gels may offer a novel strategy for enhancing the systemic immune response to RT. 展开更多
关键词 bacteria outer membrane oxygen gels tumor hypoxia RADIOTHERAPY systemic immune response
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P-sets and Its Dependence Characteristic
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作者 周玉华 赵文菊 张冠宇 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期494-498,共5页
P-sets is a set pair, it is composed of internal P-set and outer P-set, it has dynamic characteristic. By using structure of P-sets, dependence theorem and identification theorem are proposed in this paper.
关键词 p-sets dependence in sets dependence theorem identification theorem
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Function P-sets and Mining-discovery Theorems of Unknown Information Law
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作者 赵文菊 李东亚 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期488-493,共6页
Function P-sets are a set pair which are composed of function internal packetsets S F and function outer packet sets S F or (S F , S F ) are function P-sets. Function P-sets have dynamic characteristics and law charac... Function P-sets are a set pair which are composed of function internal packetsets S F and function outer packet sets S F or (S F , S F ) are function P-sets. Function P-sets have dynamic characteristics and law characteristics. Based on function P-sets, P-information law discovery theorems which has attribute supplementing-deleting are given. Mining-discovery and mining-discovery theorems of unknown information law are proposed. Function P-sets are a new theory and new method to research dynamic information laws for information systems. 展开更多
关键词 function p-sets dynamic characteristics law characteristics law sptitsynthesis law discovery
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Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions 被引量:1
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作者 Yuxue Mu Ning Zhang +7 位作者 Dongyu Wei Guoqing Yang Lilingxuan Yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang Tao Chen 《Neural Regeneration Research》 SCIE CAS 2025年第7期2116-2128,共13页
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ... A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness. 展开更多
关键词 glial fibrous acidic protein GLIOSIS Müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness
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Ownership of Mineral Resources in Outer Space
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作者 Kassim B.Kipanga Taw-Wong Youyod 《Aerospace China》 2025年第2期55-68,共14页
Ownership is an increasingly important conflict in outer space at this moment in time.Despite the principle in the Outer Space Treaty(1967),that emphasizes the importance of all states'free access to outer space b... Ownership is an increasingly important conflict in outer space at this moment in time.Despite the principle in the Outer Space Treaty(1967),that emphasizes the importance of all states'free access to outer space based on equality for exploration and use.Moreover,outer space including the Moon and other celestial bodies is not subject to national appropriation by claim of sovereignty,by means of use or occupation,or by any other means.However,outer space activity is not free from sovereignty and jurisdiction after all.Anyway,the legal situation relating to space resource exploitation and utilization activities under the adoption of United Nations is a challenge.Some scholars implied that the Outer Space Treaty(1967)clearly prohibits appropriation of whole celestial bodies but is far less clear concerning the rights of over-extracted resources.Nevertheless,the Moon Agreement(1979)promotes the idea of property ownership of over-extracted resources.It permits states to collect and remove samples of lunar minerals and other substances for further interest in scientific investigation.The application of the Moon Agreement(1979)is not only to the Moon itself but to other celestial bodies,thus potentially covering the planets and asteroids where the mining potential is considered to be limitless.Under this circumstance,numerous countries,such as the United States,Luxembourg,The United Arab Emirates,and Japan have enacted legal regimes that glorify the rights of their entities in mineral resources in outer space.However,these regimes could be disputed under the international legal framework if countries have merely interpreted and applied their rights and obligations on a national level as they understand them.Therefore,this paper purports to clarify the ownership rights in outer space and analyze the purpose of the legal situation relating to space resource exploitation and utilization activities under the adoption of the United States,Luxembourg,The United Arab Emirates,and Japan. 展开更多
关键词 outer Space Treaty(1967) Moon Agreement(1979) mineral resources in outer space
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Clinical manifestation and multimodal images of Chinese acute zonal occult outer retinopathy patients
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作者 Shu-Lin Liu Xin-Yu Zhao +1 位作者 Jing-Yuan Yang You-Xin Chen 《International Journal of Ophthalmology(English edition)》 2025年第10期1914-1921,共8页
AIM:To comprehensively examine the clinical presentations,multimodal images,and long-term follow-up of Chinese patients with acute zonal occult outer retinopathy(AZOOR),a rare inflammatory disorder.METHODS:This was a ... AIM:To comprehensively examine the clinical presentations,multimodal images,and long-term follow-up of Chinese patients with acute zonal occult outer retinopathy(AZOOR),a rare inflammatory disorder.METHODS:This was a retrospective study.A total of 20 patients(32 eyes)were included.The medical records and multimodal imaging,including wide-field fundus photography,wide-field fundus autofluorescence(FAF),and swept-source optical coherence tomography(SS-OCT)were analyzed.RESULTS:The study included 20 patients with a mean age of 38.2±10.9y,and females accounted for 60%.Lesions could involve peripapillary areas,macular region,and peripheral retina.The mean best-corrected visual acuity(BCVA)at presentation was 0.38±0.60 logMAR,with no significant difference in visual acuity between acute cases(within 6mo of onset)and chronic cases(beyond 6mo of onset;P=0.390).There was no statistically significant difference in visual acuity between eyes of acute case(within 6mo of onset)and the chronic case(beyond 6mo of onset).In some chronic case,FAF examination revealed the presence of a hyperautofluorescent(hyperAF)ring around the macular area(6/18),a phenomenon not observed in the acute case(P=0.024).A higher proportion of chronic cases showed predominantly hypoautofluorescent(hypoAF)lesions compared to the acute case(13/18 vs 2/14,P=0.0016).SS-OCT examination showed that both acute and chronic cases exhibited hyperreflective dots above the retinal pigment epithelium(RPE),and ellipsoid zone(EZ)and RPE damage.In the chronic case,eyes with hyperreflective dots above the RPE were more likely to exhibit EZ and RPE damage in the macular region compared to those without these dots.CONCLUSION:Multimodal imaging plays a crucial role in the follow-up of patients with AZOOR.In chronic cases of AZOOR,the presence of hyperreflective dots above the RPE indicates a higher likelihood of outer retinal involvement in the macular region.This study provides critical insights into the complex presentation and progression of AZOOR. 展开更多
关键词 acute zonal occult outer retinopathy fundus autofluorescence optical coherence tomography hyperreflective dots
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Electroacupuncture attenuates retinal ischemia/reperfusion injury by protecting the outer blood-retina barrier via enkephalins activate delta opioid receptor
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作者 Ping CHEN Xian-dan ZHU +5 位作者 Run-jie GUO Yong XIA Jing-ling JIN Nan-ge JIN Ying-min GU Xue-song TIAN 《World Journal of Acupuncture-Moxibustion》 2025年第3期238-253,共16页
Objectives Retinal ischemia-reperfusion(RIR)injury results in irreversible visual impairments.The disruption of the outer blood-retinal barrier(OBRB)is a major ocular pathogenic process that RIR injury affects.Current... Objectives Retinal ischemia-reperfusion(RIR)injury results in irreversible visual impairments.The disruption of the outer blood-retinal barrier(OBRB)is a major ocular pathogenic process that RIR injury affects.Current clinical strategies are limited.This study aimed to elucidate how electroacupuncture(EA)protects the OBRB against RIR injury.Methods Male Wistar rats(7 weeks old,250 g to 280 g)were used in this study.Three independent experiments were conducted.First,Opioid peptide levels were quantified using enzyme-linked immunosorbent assay(ELISA).42 rats were randomly divided into 7 groups(n=6/group):Control:No treatment;high intraocular pressure(HIOP):Acute intraocular pressure elevation-induced RIR injury;HIOP+SHAM EA:RIR injury+sham EA at Xinming(Extra acupoint)and Jingming(BL1)for 30 min(shallow needle insertion but without electric stimulation);HIOP+2 Hz EA:RIR injury+2 Hz EA at Xinming and BL1 for 30 min;HIOP+100 Hz:RIR injury+100 Hz EA at Xinming and BL1 for 30 min;HIOP+2/100 Hz EA:RIR injury+2/100 Hz EA at Xinming and BL1 for 30 min;HIOP+4/20 Hz EA:RIR injury+4/20 Hz EA at Xinming and BL1 for 30 min.Second,retinal morphology was assessed by hematoxylin and eosin(HE)staining.20 rats were randomly allocated into 4 groups(n=5/group):Control:No treatment;HIOP:Acute intraocular pressure elevation-induced RIR injury;HIOP+SHAM EA:RIR injury+sham EA at Xinming and BL1 for 30 min(shallow needle insertion but without electric stimulation);HIOP+2 Hz EA:RIR injury+2 Hz EA at Xinming and BL1 for 30 min.Third,the permeability of OBRB was evaluated using the fluorescein isothiocyanate(FITC)-dextran leakage assay.15 rats were randomly divided into 5 groups(n=3/group):Control:No treatment;HIOP:Acute intraocular pressure elevation-induced RIR injury;HIOP+SHAM EA:RIR injury+sham EA at Xinming and BL1 for 30 min(shallow needle insertion but without electric stimulation);HIOP+2 Hz EA:RIR injury+2 Hz EA at Xinming and BL1 for 30 min;Nal+HIOP+2 Hz EA:Intravitreal injection ofδ-opioid receptor antagonist Naltridole(10µl,100 nM)30 min before RIR injury induction,followed by 2 Hz EA treatment at Xinming and BL1 for 30 min.In vitro studies examined enkephalins'effects on oxygen–glucose deprivation/reperfusion(OGD/R)induced injury in ARPE‐19 cells.Cell viability was evaluated by cell counting kit-8(CCK-8)assay,and morphological changes were recorded by Molecular Devices.Apoptosis was detected by Annexin V-FITC flow cytometry.Delta opioid receptor(DOR)expression in total protein and membrane protein were analyzed by western blotting(WB).Immunofluorescence(IF)staining and WB assessed ZO-1 and Claudin-19.For cell-based assays,n indicates the number of biologically independent replicates.Results It was found that 2 Hz EA treatment increased enkephalins(methionine-enkephalin and leucine-enkephalin)levels(P<0.01),restoring the increased retinal thickness(P<0.05)and mitigating RGCs loss(P<0.05)post-RIR injury.FITC-dextran leakage in the outer retina was ameliorated by 2 Hz EA(P<0.05),reversibly countered by Naltrindole(P<0.05),a DOR antagonist.Treatment with 30µM enkephalins enhanced ARPE-19 cell viability(P<0.001,P<0.0001)and inhibited apoptosis(P<0.0001).Enkephalins elevated DOR levels in total protein(P<0.05)and membrane protein fractions(P<0.001,P<0.0001),as well as elevated ZO-1(P<0.001,P<0.01)and Claudin-19(P<0.0001,P<0.001)levels following OGD/R,counteracted by Naltrindole.Conclusion It was found that 2 Hz EA inhibits the breakdown of OBRB via enkephalins activate DOR in RIR injury. 展开更多
关键词 Retinal ischemia-reperfusion injury outer blood retinal barrier ELECTROACUPUNCTURE Delta opioid receptor ENKEPHALINS
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Jurisprudential Reflections on the Evolving Dynamics of Outer Space Governance
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作者 FENG Guodong 《Aerospace China》 2025年第2期23-28,共6页
The legal framework for outer space governance,centered on the“Five Major Treaties”,is facing significant challenges.In the face of numerous variables that will shape the future order of outer space,an intrinsic dem... The legal framework for outer space governance,centered on the“Five Major Treaties”,is facing significant challenges.In the face of numerous variables that will shape the future order of outer space,an intrinsic demand for transformation has emerged within the governance of outer space.Under the leadership of the new wave of space technology revolutions and commercial innovations,outer space governance will undergo a profound transformation.New theories in space law will emerge,engage in long-term competition,and ultimately contribute to the formation of a completely new governance structure. 展开更多
关键词 outer space governance transformation trends commercial space public rights in extraterrestrial activities
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Improved Sensitivity Encoding Parallel Magnetic Resonance Imaging Reconstruction Algorithm Based on Efficient Sum of Outer Products Dictionary Learning
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作者 DUAN Jizhong SU Yan 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期561-571,共11页
Sensitivity encoding(SENSE)is a parallel magnetic resonance imaging(MRI)reconstruction model by utilizing the sensitivity information of receiver coils to achieve image reconstruction.The existing SENSE-based reconstr... Sensitivity encoding(SENSE)is a parallel magnetic resonance imaging(MRI)reconstruction model by utilizing the sensitivity information of receiver coils to achieve image reconstruction.The existing SENSE-based reconstruction algorithms usually used nonadaptive sparsifying transforms,resulting in a limited reconstruction accuracy.Therefore,we proposed a new model for accurate parallel MRI reconstruction by combining the L0 norm regularization term based on the efficient sum of outer products dictionary learning(SOUPDIL)with the SENSE model,called SOUPDIL-SENSE.The SOUPDIL-SENSE model is mainly solved by utilizing the variable splitting and alternating direction method of multipliers techniques.The experimental results on four human datasets show that the proposed algorithm effectively promotes the image sparsity,eliminates the noise and artifacts of the reconstructed images,and improves the reconstruction accuracy. 展开更多
关键词 parallel magnetic resonance imaging(MRI) sensitivity encoding(SENSE) efficient sum of outer products dictionary learning(SOUPDIL) alternating direction method of multipliers
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基于功率外环控制的双馈风电机组故障穿越通用电磁暂态建模
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作者 朱大锐 程嘉康 +2 位作者 段建东 陈杰 邓俊 《电力系统自动化》 北大核心 2026年第2期197-207,共11页
当前风机厂家众多,控制逻辑各有差异,且多是控制结构未知的封装模型,模型应用存在较大局限性。而风电并网系统稳定性研究需要能准确反映实际风电机组各种典型故障穿越全过程响应特性的电磁暂态模型。为了解决此问题,对大量风机厂家封装... 当前风机厂家众多,控制逻辑各有差异,且多是控制结构未知的封装模型,模型应用存在较大局限性。而风电并网系统稳定性研究需要能准确反映实际风电机组各种典型故障穿越全过程响应特性的电磁暂态模型。为了解决此问题,对大量风机厂家封装模型进行故障穿越特性测试,分析测试数据并提出适用于对称、不对称故障的低、高电压穿越分阶段的全过程通用响应曲线,通过设计的每阶段转子侧、网侧功率外环参考值表达式并修改外环有功功率和无功功率参考值及控制参数,可便捷模拟不同厂家风机从故障发生到响应恢复的全过程。通过与主流厂家两种封装模型测试数据对比及误差计算分析,验证了所提建模方法对全部故障工况的适应性及通用性。 展开更多
关键词 双馈风电机组 电磁暂态模型 功率外环控制 故障穿越 建模
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深空经济的法治挑战及制度因应
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作者 高志宏 《人民论坛·学术前沿》 北大核心 2026年第2期71-80,共10页
随着深空探测技术突破与商业航天发展,深空经济已从科学探索迈向产业化初期阶段,成为培育新质生产力、重塑全球空间利益格局的主要领域,其发展呈现空间特定性、技术前沿性、范畴综合性、阶段探索性等特征。这一新兴业态对传统法律制度... 随着深空探测技术突破与商业航天发展,深空经济已从科学探索迈向产业化初期阶段,成为培育新质生产力、重塑全球空间利益格局的主要领域,其发展呈现空间特定性、技术前沿性、范畴综合性、阶段探索性等特征。这一新兴业态对传统法律制度构成挑战,引发主体界定、资源权属、责任认定等新型法律问题。因此,我国应围绕产权界定、责任分配、利益共享等关键议题,推动法律理论创新与规则体系重构,构建以国际法为引领、国内法为支撑的多层次法律框架,积极稳妥推进深空经济法律体系建设,为深空经济高质量发展提供坚实制度保障。 展开更多
关键词 深空经济 外层空间法 产权界定 国际规制
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高温后方钢管混凝土节点抗倒塌机理分析和剩余承载力评估
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作者 王景玄 刘凯 王文达 《建筑钢结构进展》 北大核心 2026年第2期10-20,共11页
钢管混凝土结构在服役的全寿命周期内可能遭受火灾、爆炸等极端灾害作用,从而引起局部或大范围的倒塌破坏。节点核心区域作为结构的关键受力部位,在遭遇火灾后会发生不同程度的高温损伤,因此有必要开展高温后该类结构的抗倒塌性能分析... 钢管混凝土结构在服役的全寿命周期内可能遭受火灾、爆炸等极端灾害作用,从而引起局部或大范围的倒塌破坏。节点核心区域作为结构的关键受力部位,在遭遇火灾后会发生不同程度的高温损伤,因此有必要开展高温后该类结构的抗倒塌性能分析。本文以方钢管混凝土柱-H型钢梁外环板式节点作为研究对象,基于顺序热-力耦合方法采用ABAQUS软件中的通用分析模块Standard建立了高温后该类节点倒塌精细化数值模型,对比常温下该类节点的倒塌试验结果,分析了该类节点在经历不同的历史最高环境温度(200℃、400℃、600℃、800℃)并自然冷却后的抗倒塌性能。结果表明,节点核心区环板和钢梁连接部位损伤是诱发该类结构破坏的直接原因,并且随着环境温度升高节点损伤和断裂加剧。此外,高温后节点的荷载-位移曲线发展趋势经历了弯曲阶段、混合阶段、悬链线阶段和破坏阶段,当最高温度等于或超过600℃时,节点承载能力和变形能力大幅下降。最后,分析了该类节点在倒塌过程中抗力机制的演变,并对该类节点在高温后的抗倒塌剩余承载能力进行评估,可为工程设计提供参考。 展开更多
关键词 钢管混凝土 外环板式节点 高温损伤 连续性倒塌 热-力耦合方法 精细化数值模型 剩余承载力
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RELEASE KINETICS OF MONOLITHIC MATRIX COATED WITH OUTER MEMBRANE SYSTEM 被引量:1
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作者 石巍 张国亮 +1 位作者 张凤宝 刘瑛 《Transactions of Tianjin University》 EI CAS 2001年第1期56-60,共5页
The reservoir-monolithic type of the controlled release systems is investigated currently,however,the existing kinetic model could not describe the release process well because the release kinetics is rather complicat... The reservoir-monolithic type of the controlled release systems is investigated currently,however,the existing kinetic model could not describe the release process well because the release kinetics is rather complicated.In this paper,a simplified release kinetic model for diffusion-controlled monolithic matrix coated with outer membrane systems is proposed and verified by the experimental data of mercaptopurinum release experiment.It shows that the model can well describe the release mechanism (the relative error is under 3%) when drug loading (C d) is above its solubility limit (C s).At the same time,the release characteristics of special cases (D mD f and D mD f) are discussed theoretically.When D mD f the release rate becomes constant,namely,zero order release,and the release rate is independent of the drug membrane.This result provides the theoretical basis for the system of zero order release as well as how to control the release rate and the amount of drug release.When D mD f,the release rate is dependent on the drug release coefficient in the monolithic matrix,solubility and drug loading but independent of the process in the outer membrane,and it is similar to monolithic matrix type. 展开更多
关键词 controlled release DIFFUSION mercaptopurinum monolithic matrix outer membrane
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整体型自润滑关节轴承精密成形技术现状及发展趋势
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作者 谷瑞杰 蔡欣辰 +4 位作者 屈勇全 王彦章 张壮雅 张晓杭 王强 《河南科技大学学报(自然科学版)》 北大核心 2026年第1期85-94,M0006,M0007,共12页
关节轴承作为高端装备的核心零部件,可传递载荷并进行斜转、摆动等复杂运动,广泛应用于军工、航空航天等关键领域,其精密成形技术直接决定关节轴承的成形质量与服役性能,通过介绍整体型自润滑关节轴承成形过程中常见的两类成形工艺:模... 关节轴承作为高端装备的核心零部件,可传递载荷并进行斜转、摆动等复杂运动,广泛应用于军工、航空航天等关键领域,其精密成形技术直接决定关节轴承的成形质量与服役性能,通过介绍整体型自润滑关节轴承成形过程中常见的两类成形工艺:模具挤压成形、旋压成形,总结了国内外整体型自润滑关节轴承成形技术现状,并简述了有限元分析在工艺优化中的应用,最后指出了未来发展趋势:以“高精度、无损伤”为核心,通过迭代优化算法对成形工艺进行多目标优化,以满足在高温、腐蚀等极端工况下的正常运作,并结合3D打印等先进技术研发新型成形工艺。 展开更多
关键词 自润滑关节轴承 整体型外圈 成形技术 塑性成形
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上海常见绿化树种叶功能性状对大气和土壤环境的响应
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作者 王九洲 王小玲 +3 位作者 庞育兰 郭雪艳 宋坤 达良俊 《生态学报》 北大核心 2026年第3期1182-1192,共11页
为探究城市绿化树种叶功能性状的变异及其环境驱动因素,以上海环城生态公园带62个样方9种常见树种为研究对象,通过测定9种植物叶功能性状,分析其对大气污染物和土壤养分的响应。结果表明:(1)上海常见树种的叶功能性状受不同环境因素驱动... 为探究城市绿化树种叶功能性状的变异及其环境驱动因素,以上海环城生态公园带62个样方9种常见树种为研究对象,通过测定9种植物叶功能性状,分析其对大气污染物和土壤养分的响应。结果表明:(1)上海常见树种的叶功能性状受不同环境因素驱动,叶碳含量、叶氮含量、叶磷含量、叶钾含量、叶面积、比叶面积、叶干物质含量与叶形指数受大气和土壤环境显著影响。(2)大气污染物中,PM_(2.5)与叶碳含量负相关;O_(3)与叶形指数正相关,与叶氮含量负相关;VOCs与比叶面积、叶氮含量和叶磷含量正相关,与叶碳含量和叶干物质含量负相关。(3)土壤养分中,土壤总氮含量、土壤总磷含量与叶钾含量负相关;土壤总钾含量与叶氮含量和叶钾含量正相关;土壤速效钾含量与叶磷含量正相关;土壤氨氮含量与叶碳含量和叶氮含量负相关;土壤硝态氮含量与叶面积、叶氮含量正相关。(4)相较于大气污染物,土壤养分在叶功能性状变异的解释中具有更高相对重要性。综上,上海城市森林的管理建设与功能评估过程中需要考量城市异质环境对树木叶功能性状的影响。 展开更多
关键词 环城生态公园带 叶功能性状 土壤养分 大气污染物
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Study on Outer Membrane Protein Patterns of Escherichia coli O38,O53 and O75 Isolated from Chickens
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作者 张艳英 高桂生 +5 位作者 高光平 史秋梅 刘玉芹 张海莹 房海 陈翠珍 《Agricultural Science & Technology》 CAS 2012年第10期2070-2072,2122,共4页
[Objective] This study aimed to investigate the outer membrane protein (OMP) patterns of Escherichia coli 038, 053 and 075 isolates from chickens. [Method] Eight pathogenic E. coil isolates with various serotypes we... [Objective] This study aimed to investigate the outer membrane protein (OMP) patterns of Escherichia coli 038, 053 and 075 isolates from chickens. [Method] Eight pathogenic E. coil isolates with various serotypes were used as experimental materials to extract OMP by using supersonic schizolysis method and Sarcosyl. After SDS-PAGE electrophoresis, OMP patterns of the extracted products were determined based on the OMP model diagram. [Result] OMP of eight E. coil isolates with three serotypes were divided into three patterns, to be specific, 2 075 isolates respectively belonged to OMP-I and OMP-II pattern, 1 053 isolate belonged to OMP-II pattern, and 5 038 isolates belonged to OMP-I and OMP-III pattern. [Conclusion] Experimental results showed that E. coli isolates with the same serotype may belong to completely different OMP patterns, while serologically unrelated isolates may belong to the same OMP pattern. OMP of E. coil isolates with the same serotype may generate genetic differentiation; in addition, OMP of E. coli isolates with different serotypes may have different genetic correlation. 展开更多
关键词 Escherichia coli from chickens outer membrane protein pattern SDS- PAGE
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不同连接形式冻结管承载力及变形对比研究
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作者 王锦恒 王彬 +1 位作者 张子浩 梁秀玲 《煤炭工程》 北大核心 2026年第1期208-215,共8页
为提升人工冻结法的安全性与可靠性,通过对比不同规格及低温条件下的外衬与内衬焊接构造冻结管的力学性能差异,明确其承载能力和变形特性对工程选型的影响。采用内衬与外衬两种不同焊接方式的冻结管,分别选取Φ140 mm×5 mm+Φ140 m... 为提升人工冻结法的安全性与可靠性,通过对比不同规格及低温条件下的外衬与内衬焊接构造冻结管的力学性能差异,明确其承载能力和变形特性对工程选型的影响。采用内衬与外衬两种不同焊接方式的冻结管,分别选取Φ140 mm×5 mm+Φ140 mm×6 mm、Φ140 mm×6 mm+Φ140 mm×6 mm、Φ140 mm×5 mm+Φ140 mm×5 mm三种规格,在模拟低温环境中系统测试其轴向承载力和挠度变形特性,结果显示:在相同尺寸和实验条件的对比下,外衬构造冻结管的平均承载力明显低于内衬构造管,但其挠度值更高。这表明焊接构造形式对冻结管力学性能具有直接影响,内衬构造抗压性能更优,而外衬构造则具有更强的变形适应性能。采用曲率检验法对两种不同焊接方式的冻结管进行安全评估,结果表明两种焊接方式的冻结管均满足安全规范要求。 展开更多
关键词 人工冻结法 冻结管 焊接构造 内衬 外衬 力学特性
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