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不同规模滑坡入水诱发涌浪灾害特征差异性分析 被引量:1
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作者 王雷 解明礼 +2 位作者 黄会宝 柯虎 高强 《人民珠江》 2024年第2期18-28,共11页
针对不同规模滑坡入水产生的涌浪开展三维数值分析,分析不同规模滑坡入水诱发涌浪灾害特征,如涌浪高度、涌浪速度、对岸爬高等,探讨不同规模滑坡入水引发涌浪对大坝的影响。利用FLOW-3D数值模拟方法对滑坡失稳过程、涌浪形成及传播、涌... 针对不同规模滑坡入水产生的涌浪开展三维数值分析,分析不同规模滑坡入水诱发涌浪灾害特征,如涌浪高度、涌浪速度、对岸爬高等,探讨不同规模滑坡入水引发涌浪对大坝的影响。利用FLOW-3D数值模拟方法对滑坡失稳过程、涌浪形成及传播、涌浪爬升、涌浪回流的全过程进行模拟分析。结果显示:310万m^(3)滑坡入水产生涌浪在对岸最大爬高为54.5 m,坝前涌浪高度为6.69 m,涌浪在右岸坝肩处有小范围漫坝;80万m^(3)滑坡入水产生涌浪在对岸最大爬高为26.00 m,坝前涌浪高度为5.38 m,涌浪对大坝安全无影响。结果表明:310万m^(3)滑坡入水诱发涌浪与80万m^(3)滑坡入水诱发涌浪相比,致灾性较强。 展开更多
关键词 不同规模滑坡 涌浪灾害 FLOW-3D数值模拟 致灾性
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Proppant transport in rough fracture networks using supercritical CO_(2)
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作者 Yong Zheng Meng-Meng Zhou +6 位作者 Ergun Kuru Bin Wang Jun Ni Bing Yang ke hu Hai huang Hai-Zhu Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1852-1864,共13页
Proppant transport within fractures is one of the most critical tasks in oil,gas and geothermal reservoir stimulation,as it largely determines the ultimate performance of the operating well.Proppant transport in rough... Proppant transport within fractures is one of the most critical tasks in oil,gas and geothermal reservoir stimulation,as it largely determines the ultimate performance of the operating well.Proppant transport in rough fracture networks is still a relatively new area of research and the associated transport mechanisms are still unclear.In this study,representative parameters of rough fracture surfaces formed by supercritical CO_(2) fracturing were used to generate a rough fracture network model based on a spectral synthesis method.Computational fluid dynamics(CFD)coupled with the discrete element method(DEM)was used to study proppant transport in this rough fracture network.To reveal the turning transport mechanism of proppants into branching fractures at the intersections of rough fracture networks,a comparison was made with the behavior within smooth fracture networks,and the effect of key pumping parameters on the proppant placement in a secondary fracture was analyzed.The results show that the transport behavior of proppant in rough fracture networks is very different from that of the one in the smooth fracture networks.The turning transport mechanisms of proppant into secondary fractures in rough fracture networks are gravity-driven sliding,high velocity fluid suspension,and fracture structure induction.Under the same injection conditions,supercritical CO_(2)with high flow Reynolds number still has a weaker ability to transport proppant into secondary fractures than water.Thickening of the supercritical CO_(2)needs to be increased beyond a certain value to have a significant effect on proppant carrying,and under the temperature and pressure conditions of this paper,it needs to be increased more than 20 times(about 0.94 m Pa s).Increasing the injection velocity and decreasing the proppant concentration facilitates the entry of proppant into the branching fractures,which in turn results in a larger stimulated reservoir volume.The results help to understand the proppant transport and placement process in rough fracture networks formed by reservoir stimulation,and provide a theoretical reference for the optimization of proppant pumping parameters in hydraulic fracturing. 展开更多
关键词 Reservoir stimulation CCUS Rough fracture network Supercritical CO_(2) Proppanttransport
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Development and Application of Ultrafast Circular Dichroism Spectroscopy Techniques
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作者 Tong Cui Menghui Jia +5 位作者 Peicong Wu ke hu Xueli Wang Sanjun Zhang Haifeng Pan Jinquan Chen 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期449-460,I0093,共13页
Chirality hold broad applications in life sciences,quantum devices,and various other areas.Traditionally,molecular chirality can be characterized by using steady-state circular dichroism spectroscopy.However,the techn... Chirality hold broad applications in life sciences,quantum devices,and various other areas.Traditionally,molecular chirality can be characterized by using steady-state circular dichroism spectroscopy.However,the techniques that can characterize excited state chirality are progressively capturing the public interest as it can provide the dynamic information for chirality generation and transfer.In this review,we focus on the theoretical background and the developmental history of femtosecond time-resolved circular dichroism spectroscopy(TRCD)techniques around the world.Additionally,we provide examples to showcase the utility of these techniques in the analysis of the dynamical molecular chemical structures,the investigation of molecular chirality generation,and the detection of electron spin dynamics in semiconductor quantum dots. 展开更多
关键词 Excited state chirality Femtosecond time-resolved circular dichroism spectroscopy Ultrafast dynamics Chiral spectra
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Retinal microcirculation changes in prediabetic patients with shortterm increased blood glucose using optical coherence tomography angiography
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作者 Bing-Jing Lv Hang-Jia Zuo +6 位作者 Qi-Fu Li Fan-Fan huang Tong Zhang Rong-Xi huang Shi-Jie Zheng Wen-Juan Wan ke hu 《World Journal of Radiology》 2024年第9期407-417,共11页
BACKGROUND Retinal microcirculation alterations are early indicators of diabetic microvascular complications.Optical coherence tomography angiography(OCTA)is a noninvasive method to assess these changes.This study ana... BACKGROUND Retinal microcirculation alterations are early indicators of diabetic microvascular complications.Optical coherence tomography angiography(OCTA)is a noninvasive method to assess these changes.This study analyzes changes in retinal microcirculation in prediabetic patients during short-term increases in blood glucose using OCTA.AIM To investigate the changes in retinal microcirculation in prediabetic patients experiencing short-term increases in blood glucose levels using OCTA.METHODS Fifty volunteers were divided into three groups:Group 1[impaired fasting glucose(IFG)or impaired glucose tolerance(IGT)],Group 2(both IFG and IGT),and a control group.Retinal microcirculation parameters,including vessel density(VD),perfusion density(PD),and foveal avascular zone(FAZ)metrics,were measured using OCTA.Correlations between these parameters and blood glucose levels were analyzed in both the fasting and postprandial states.RESULTS One hour after glucose intake,the central VD(P=0.023),central PD(P=0.026),and parafoveal PD(P<0.001)were significantly greater in the control group than in the fasting group.In Group 1,parafoveal PD(P<0.001)and FAZ circularity(P=0.023)also increased one hour after glucose intake.However,no significant changes were observed in the retinal microcirculation parameters of Group 2 before or after glucose intake(P>0.05).Compared with the control group,Group 1 had a larger FAZ area(P=0.032)and perimeter(P=0.018),whereas Group 2 had no significant differences in retinal microcirculation parameters compared with the control group(P>0.05).Compared with Group 1,Group 2 had greater central VD(P=0.013)and PD(P=0.008)and a smaller FAZ area(P=0.012)and perimeter(P=0.010).One hour after glucose intake,Group 1 had a larger FAZ area(P=0.044)and perimeter(P=0.038)than did the control group,whereas Group 2 showed no significant differences in retinal microcirculation parameters compared with the control group(P>0.05).Group 2 had greater central VD(P=0.042)and PD(P=0.022)and a smaller FAZ area(P=0.015)and perimeter(P=0.016)than Group 1.At fasting,central PD was significantly positively correlated with blood glucose levels(P=0.044),whereas no significant correlations were found between blood glucose levels and OCTA parameters one hour after glucose intake.CONCLUSION A short-term increase in blood glucose has a more pronounced effect on retinal microcirculation in prediabetic patients with either IFG or IGT. 展开更多
关键词 PREDIABETES Blood glucose Optical coherence tomography angiography Retinal microcirculation Central vessel density Impaired fasting glucose Impaired glucose tolerance
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浅谈河床式水电站运行期增设大坝渗流监测设施
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作者 刘贺 柯虎 +2 位作者 彭涛 高志良 罗忠平 《四川水力发电》 2024年第S01期138-142,147,共6页
测压管是河床式水电站混凝土坝重要的渗流监测设施,对于无法满足监测需求的测压管,应采取扫孔或重新钻孔的措施恢复其功能。在运行期混凝土坝上钻孔风险极大,类似工程较少。通过工程实例,从钻孔选点、钻孔施工、测压管埋设等方面,探讨... 测压管是河床式水电站混凝土坝重要的渗流监测设施,对于无法满足监测需求的测压管,应采取扫孔或重新钻孔的措施恢复其功能。在运行期混凝土坝上钻孔风险极大,类似工程较少。通过工程实例,从钻孔选点、钻孔施工、测压管埋设等方面,探讨了运行期河床式混凝土坝钻孔埋管实施的关键技术,分析了工程实施后的监测效果,同时为有类似需求的工程提供技术参考。 展开更多
关键词 河床式水电站 混凝土坝 监测 钻孔 测压管
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Countermeasures for Development and Present Situation of Chives in Xiaogang Town, Xiaogan City, Hubei Province
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作者 Yue CHEN Chunfu XIE +10 位作者 Hongping LIU huashu LIU Jian WANG Ming ZHENG Ju YUE Changbing LIU Dan LIU Hanhua TANG Yuchao PENG Yonggang NIU ke hu 《Asian Agricultural Research》 2013年第5期50-51,57,共3页
Through the overview of main problems existing in chives production, its current situation and history, the thesis puts forward countermeasures for developing chives industrialization in Xiaogang Town, Xiaogan City.
关键词 Chives PRESENT SITUATION of INDUSTRY Countermeasur
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库水位变化时陡倾软弱顺层岩质滑坡变形机制 被引量:6
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作者 张琪 巨能攀 +3 位作者 张成强 张建军 柯虎 刘恒 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第2期206-217,共12页
研究库水位动态变化时陡倾软弱顺层岩质滑坡的变形机制,为库岸滑坡防治及库水调度提供帮助。以四川省大渡河某水电站开顶滑坡为例,通过野外调查资料、库水位及地面监测数据综合分析,研究滑坡结构及变形破坏特征;建立二维地质模型,利用... 研究库水位动态变化时陡倾软弱顺层岩质滑坡的变形机制,为库岸滑坡防治及库水调度提供帮助。以四川省大渡河某水电站开顶滑坡为例,通过野外调查资料、库水位及地面监测数据综合分析,研究滑坡结构及变形破坏特征;建立二维地质模型,利用离散元模拟蓄水前后陡倾顺层岩质滑坡变形响应过程,结合有限元进一步分析库水作用下岸坡稳定性变化规律。研究结果表明,岸坡特殊的地质构造和岩性是控制滑坡产生的主要因素,水库蓄水诱发了滑坡的变形,库水位变化进一步加速了变形进程。当库水位以4.8 m/d、3.84 m/d、1.92 m/d的速率上升时,坡体稳定性呈现先增后减的趋势;当以小于0.5 m/d的速率下降时,岸坡变形不明显,但稳定性急剧降低,极有可能增加变形速率,加剧变形,导致大范围失稳破坏。在水库调度过程中,为避免渗流作用对岸坡稳定性的影响,库水位变化应保持在较小的速率平稳运行。 展开更多
关键词 库岸滑坡 陡倾软弱顺层岩质滑坡 变形机制 离散元数值模拟 开顶滑坡
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考虑热学参数空间变异性的重力坝施工期温度及应力场分析 被引量:1
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作者 沈定斌 柯虎 +2 位作者 赵杰 卢祥 裴亮 《中国农村水利水电》 北大核心 2023年第2期218-225,共8页
碾压混凝土坝的温控防裂一直是工程建设中的关键技术问题。由于浇筑仓面大、碾压质量不均匀以及混凝土的非均质性,碾压混凝土坝材料参数具有显著空间变异性。传统混凝土坝温度与应力分析常采用确定性计算,忽略了参数空间变异的影响,导... 碾压混凝土坝的温控防裂一直是工程建设中的关键技术问题。由于浇筑仓面大、碾压质量不均匀以及混凝土的非均质性,碾压混凝土坝材料参数具有显著空间变异性。传统混凝土坝温度与应力分析常采用确定性计算,忽略了参数空间变异的影响,导致温度及应力场模拟不够合理。本文基于随机场理论和中心点离散方法,提出了混凝土热学参数空间变异有限元模拟方法。TJ大坝案例分析表明,考虑热学参数空间变异后,最高温度场和最大拉应力场在平均效应上与确定性结果基本一致,热学参数空间变异显著影响大坝混凝土结构的最高温度和最大应力。随机温度应力场下结构部分位置温度及应力超过了允许值,意味着依据传统确定性温度应力分析结果提出的温控措施可能偏危险。提出的随机温度应力分析方法对重力坝施工期温控措施的制定提供了方法支持。 展开更多
关键词 重力坝 热学参数 空间变异 施工期 温度应力
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A developed dual-site Langmuir model to represent the high-pressure methane adsorption and thermodynamic parameters in shale 被引量:3
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作者 ke hu Qian Zhang +1 位作者 Yufei Liu Muhammad Abdurrahman Thaika 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第5期21-37,共17页
Comprehending the mechanism of methane adsorption in shales is a crucial step towards optimizing the development of deep-buried shale gas. This is because the methane adsorbed in shale represents a significant proport... Comprehending the mechanism of methane adsorption in shales is a crucial step towards optimizing the development of deep-buried shale gas. This is because the methane adsorbed in shale represents a significant proportion of the subsurface shale gas resource. To properly characterize the methane adsorption on shale, which exhibits diverse mineral compositions and multi-scale pore sizes, it is crucial to capture the energy heterogeneity of the adsorption sites. In this paper, a dual-site Langmuir model is proposed, which accounts for the temperature and pressure dependence of the density of the adsorbed phase. The model is applied to the isothermals of methane adsorption on shale, at pressures of up to 30 MPa and temperatures ranging from 40 to 100 ℃. The results show that the proposed model can describe the adsorption behavior of methane on shale more accurately than conventional models, which assume a constant value for the density of adsorbed phase. Furthermore, the proposed model can be extrapolated to higher temperatures and pressures. Thermodynamic parameters were analyzed using correctly derived equations. The results indicate that the widely used, but incorrect, equation would underestimate the isosteric heat of adsorption. Neglecting the real gas behavior, volume of the adsorbed phase, and energy heterogeneity of the adsorption sites can lead to overestimation of the isosteric heat of adsorption. Furthermore, the isosteric heat evaluated from excess adsorption data can only be used to make a rough estimate of the real isosteric heat at very low pressure. 展开更多
关键词 Shale gas Adsorption-Dual-site Langmuir model Energy heterogeneity Isosteric heat
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Genipin relieves diabetic retinopathy by down-regulation of advanced glycation end products via the mitochondrial metabolism related signaling pathway 被引量:2
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作者 ke-Xin Sun Yan-Yi Chen +4 位作者 Zhen Li Shi-Jie Zheng Wen-Juan Wan Yan Ji ke hu 《World Journal of Diabetes》 SCIE 2023年第9期1349-1368,共20页
BACKGROUND Glycation is an important step in aging and oxidative stress,which can lead to endothelial dysfunction and cause severe damage to the eyes or kidneys of diabetics.Inhibition of the formation of advanced gly... BACKGROUND Glycation is an important step in aging and oxidative stress,which can lead to endothelial dysfunction and cause severe damage to the eyes or kidneys of diabetics.Inhibition of the formation of advanced glycation end products(AGEs)and their cell toxicity can be a useful therapeutic strategy in the prevention of diabetic retinopathy(DR).Gardenia jasminoides Ellis(GJE)fruit is a selective inhibitor of AGEs.Genipin is an active compound of GJE fruit,which can be employed to treat diabetes.AIM To confirm the effect of genipin,a vital component of GJE fruit,in preventing human retinal microvascular endothelial cells(hRMECs)from AGEs damage in DR,to investigate the effect of genipin in the down-regulation of AGEs expression,and to explore the role of the CHGA/UCP2/glucose transporter 1(GLUT1)signal pathway in this process.METHODS In vitro,cell viability was tested to determine the effects of different doses of glucose and genipin in hRMECs.Cell Counting Kit-8(CCK-8),colony formation assay,flow cytometry,immunofluorescence,wound healing assay,transwell assay,and tube-forming assay were used to detect the effect of genipin on hRMECs cultured in high glucose conditions.In vivo,streptozotocin(STZ)induced mice were used,and genipin was administered by intraocular injection(IOI).To explore the effect and mechanism of genipin in diabetic-induced retinal dysfunction,reactive oxygen species(ROS),mitochondrial membrane potential(MMP),and 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose(2-NBDG)assays were performed to explore energy metabolism and oxidative stress damage in high glucose-induced hRMECs and STZ mouse retinas.Immunofluorescence and Western blot were used to investigate the expression of inflammatory cytokines[vascular endothelial growth factor(VEGF),SCG3,tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β,IL-18,and nucleotide-binding domain,leucine-rich-containing family,pyrin domain-containing 3(NLRP3)].The protein expression of the receptor of AGEs(RAGE)and the mitochondria-related signal molecules CHGA,GLUT1,and UCP2 in high glucose-induced hRMECs and STZ mouse retinas were measured and compared with the genipin-treated group.RESULTS The results of CCK-8 and colony formation assay showed that genipin promoted cell viability in high glucose(30 mmol/L D-Glucose)-induced hRMECs,especially at a 0.4μmol/L dose for 7 d.Flow cytometry results showed that high glucose can increase apoptosis rate by 30%,and genipin alleviated cell apoptosis in AGEs-induced hRMECs.A high glucose environment promoted ATP,ROS,MMP,and 2-NBDG levels,while genipin inhibited these phenotypic abnormalities in AGEs-induced hRMECs.Furthermore,genipin remarkably reduced the levels of the pro-inflammatory cytokines TNF-α,IL-1β,IL-18,and NLRP3 and impeded the expression of VEGF and SCG3 in AGEs-damaged hRMECs.These results showed that genipin can reverse high glucose induced damage with regard to cell proliferation and apoptosis in vitro,while reducing energy metabolism,oxidative stress,and inflammatory injury caused by high glucose.In addition,ROS levels and glucose uptake levels were higher in the retina from the untreated eye than in the genipin-treated eye of STZ mice.The expression of inflammatory cytokines and pathway protein in the untreated eye compared with the genipin-treated eye was significantly increased,as measured by Western blot.These results showed that IOI of genipin reduced the expression of CHGA,UCP2,and GLUT1,maintained the retinal structure,and decreased ROS,glucose uptake,and inflammation levels in vivo.In addition,we found that SCG3 expression might have a higher sensitivity in DR than VEGF as a diagnostic marker at the protein level.CONCLUSION Our study suggested that genipin ameliorates AGEs-induced hRMECs proliferation,apoptosis,energy metabolism,oxidative stress,and inflammatory injury,partially via the CHGA/UCP2/GLUT1 pathway.Control of advanced glycation by IOI of genipin may represent a strategy to prevent severe retinopathy and vision loss. 展开更多
关键词 GENIPIN Human retinal microvascular endothelial cells ANGIOGENESIS VASCULARIZATION Secretogranin III Diabetic retinopathy
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Photo-and Electrocatalytic CO_(2)Reduction Based on Stable Lead-Free Perovskite Cs2PdBr6 被引量:1
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作者 Daofu Wu Cheng Wang +7 位作者 Benjun huo ke hu Xinchun Mao Zhigang Geng Qiang huang Wenxia Zhang Jie Zeng Xiaosheng Tang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第5期364-371,共8页
All-inorganic lead-free palladium(Pd)halogen perovskites with prominent optoelectronic properties provide admirable potential for selective photo-and electroreduction of CO_(2).But it remains unachieved for effectivel... All-inorganic lead-free palladium(Pd)halogen perovskites with prominent optoelectronic properties provide admirable potential for selective photo-and electroreduction of CO_(2).But it remains unachieved for effectively converting the CO_(2)to CO with high selectivity on Pd-based perovskites driven by solar light or electricity.Herein,high-quality Cs_(2)PdBr_(6)microcrystals and nanocrystals were synthesized through a facile antisolvent method.Among all the reported pure-phase perovskites,the Cs_(2)PdBr_(6)nanocrystals synthesized at 50℃performed the highest effectiveness on CO_(2)to CO conversion generating 73.8μmol g^(-1)of CO yield with 100%selectivity under visible light illumination(λ>420 nm)for 3 h.Meanwhile,for the first time,we report a new application of lead-free perovskites,in which they are applied to electrocatalysis of CO_(2)reduction reaction.Noticeably,they showed significant electrocatalytic activity(Faradaic yield:78%for CO)and operation stability(10 h).And the surface reaction intermediates were dynamically monitored and precisely unraveled according to the in situ diffuse reflectance infrared Fourier transform spectra investigation.In combination with the density functional theory calculation,the reaction mechanism and pathways were revealed.This work not only provides significant strategies to enhance the photocatalytic performance of perovskites,but also shows excellent potential for their application in electrocatalysis. 展开更多
关键词 CO_(2)reduction CRYSTALLINITY lead-free perovskites morphology photocatalysis reaction mechanism
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Effectiveness and the nomogram of small incision lenticule extraction in the correction of myopic anisometropia in adults 被引量:1
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作者 Tong Zhang Lu Zhu +12 位作者 Hang-Jia Zuo Zhi-Jun Chen Yan Ji Xin Yang Xiao-Rong Lu Qiong Wu Qing Wang Jiu-Yi Xia Meng Li Chun-Jiang Zhou Yao Wang ke hu Wen-Juan Wan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第11期1838-1844,共7页
AIM:To evaluate the safety,effectiveness,and predictability of small incision lenticule extraction(SMILE)for the treatment of anisometropia,and to explore the personalized design scheme of SMILE in correcting adult my... AIM:To evaluate the safety,effectiveness,and predictability of small incision lenticule extraction(SMILE)for the treatment of anisometropia,and to explore the personalized design scheme of SMILE in correcting adult myopia anisometropia based on the nomogram.METHODS:It’s a prospective cohort study.Patients with anisometropic myopia of refractive difference≥2.0 diopters(D)who underwent SMILE between September 2020 and March 2021 were enrolled.Clinical features and visual function were assessed preoperatively and at 1wk,1,3,and 6mo after the operation.The examination included tests for uncorrected distance visual acuity(UDVA),corrected distance visual acuity(CDVA),refractive errors,effectiveness index(preoperative CDVA/postoperative UDVA),safety index(postoperative CDVA/preoperative CDVA),nomogram and stereoscopic function.Paired t-test,Wilcoxon signed-rank test and repeated-measures analyses of variance were used for continuous variables,and Pearson Chi-squared test was used for categorical variables.RESULTS:The study involved 45 consecutive patients(average age:25.0±6.9y;82 out of 90 eyes underwent SMILE,while 8 eyes were not operated).The average preoperative spherical equivalent(SE)was-4.74±0.22 D.Six months after surgery,the effectiveness index was 1.05±0.12,and the safety index was 1.09±0.11.Seventy eyes(85.4%)exhibited SE correction error within±0.5 D.The percentage of eyes with Titmus stereoscopic function equal to or less than 200”significantly increased from 55.6%preoperatively to 88.9%postoperatively(P<0.05).There was statistically significant difference between higher myopia eyes and contralateral eyes in average nomogram value/spherical refraction ratio.CONCLUSION:SMILE is safe,effective and predictable in correcting myopic anisometropia,and it improves stereoscopic visual function of anisometropia patients.The precise and individualized design of the nomogram is a vital element to ensure the balance of both eyes after SMILE. 展开更多
关键词 refractive surgery small incision lenticule extraction ANISOMETROPIA NOMOGRAM
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IP Lyn:A Totally Eclipsing Contact Binary with an Extremely Low Mass Ratio
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作者 Zi-Xuan Yin Zi-Bin Meng +4 位作者 Pei-Ru Wu Xu-Dong Zhang Yun-Xia Yu ke hu Fu-Yuan Xiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期206-219,共14页
We present the first photometric and orbital period investigations for a neglected totally eclipsing contact binary IP Lyn.The photometric solutions derived from both ground-based and several surveys'observations ... We present the first photometric and orbital period investigations for a neglected totally eclipsing contact binary IP Lyn.The photometric solutions derived from both ground-based and several surveys'observations suggest that it is a shallow contact binary with an extremely low mass ratio of 0.055.The weak asymmetry observed in our multiple band light curves can be interpreted as a result of an active cool spot on the primary.The absolute physical parameters were determined with the Gaia-distance-based method and checked by an empirical relation.Combining the eclipse timings collected from the literature and those derived from our and variable surveys'observations,we find that IP Lyn has been undergoing a secular orbital period increase for the past two decades,implying a mass transfer from the less massive secondary to the primary.By comparing the current parameters with the critical instability ones,we infer that IP Lyn is currently stable in spite of its relatively low mass ratio and orbital angular momentum.Finally,from a catalog of 117 extremely low mass ratio contact binaries,we find that their orbital angular momenta are significantly lower than those of the contact binaries with a relatively high mass ratio,suggesting they should be at the late evolutionary stage of a contact binary. 展开更多
关键词 (stars")binaries(including multiple) close-(stars:)binaries eclipsing-stars evolution-stars individual(IP Lyn)
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Safety and Efficacy of Endovascular Aortic Repair for Abdominal Aortic Aneurysms with a Hostile Neck Anatomy
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作者 Zun-xiang ke Ge-zheng CHEN +6 位作者 ke hu Shan ZHANG Peng ZHOU Dian-xi CHEN Yi-qing LI Qin LI Chao YANG 《Current Medical Science》 SCIE CAS 2023年第6期1221-1228,共8页
Objective This study aimed to investigate the safety and efficacy of endovascular aortic repair(EVAR)for the treatment of an abdominal aortic aneurysm(AAA)with a hostile neck anatomy(HNA).Methods From January 1,2015 t... Objective This study aimed to investigate the safety and efficacy of endovascular aortic repair(EVAR)for the treatment of an abdominal aortic aneurysm(AAA)with a hostile neck anatomy(HNA).Methods From January 1,2015 to December 31,2019,a total of 259 patients diagnosed with an AAA who underwent EVAR were recruited into this study.Based on the morphological characteristics of the proximal neck anatomy,the patients were divided into the HNA group and the friendly neck anatomy(FNA)group.The patients were followed up for up to 4 years.Results The average follow-up time was 1056.1±535.5 days.Type I endoleak occurred in 4 patients in the HNA group,and 2 patients in the FNA group.Neither death nor intraoperative switch to open repair occurred in either group.The time of the operation was significantly longer in the HNA group(FNA vs.HNA,99.2±51.1 min vs.117.5±63.8 min,P=0.011).There were no significant differences in short-term clinical success rate(P=0.228)or midterm clinical success rate(P=0.889)between the two groups.The overall mortality rate was 10.4%,and Kaplan-Meier survival analysis indicated that the two groups had similar cumulative survival rates at the end of the follow-up period(P=0.889).Conclusion EVAR was feasible and safe in patients with an AAA with a proximal HNA.The early and midterm results were promising;however,further studies are needed to verify the long-term effectiveness of EVAR. 展开更多
关键词 abdominal aortic aneurysm hostile aneurysm neck endovascular aortic repair ENDOLEAK PROGNOSIS
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Evaluation of childhood developing via optical coherence tomography-angiography in Qamdo,Tibet,China:A prospective cross-sectional,school-based study
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作者 ke-Xin Sun Yong-Guo Xiang +7 位作者 Tong Zhang Sheng-Lan Yi Jiu-Yi Xia Xin Yang Shi-Jie Zheng Yan Ji Wen-Juan Wan ke hu 《World Journal of Clinical Cases》 SCIE 2023年第23期5479-5493,共15页
BACKGROUND Optical coherence tomography angiography(OCTA)is a new and reliable machine used to evaluate retinal structure and macular perfusion in children.The use of OCTA under bad condition such as high altitude,low... BACKGROUND Optical coherence tomography angiography(OCTA)is a new and reliable machine used to evaluate retinal structure and macular perfusion in children.The use of OCTA under bad condition such as high altitude,low atmospheric oxygen,and low humidity,in children is rarely.AIM To quantify the macular micro-vasculature in healthy children of various ages using OCTA in Qamdo.METHODS Design:Prospective cross-sectional,school-based study.Three hundred and fortyseven normal students from 9 schools in 4 different areas in Qamdo were included.OCTA was performed on a 3 mm×3 mm area centered on the macular region and macular cube 512×128 showed details in macular.Early treatment of diabetic retinopathy study Vessel Flow Density(VD)of the macular central vascular plexus density(CVD),inner vascular plexus density(IVD),full vascular plexus density(FVD),and the size of the foveal avascular zone(FAZ)were measured.All these results corrected by t/s=3.382×0.01306×(axial length-1.82).The differences were compared among various ages,sexes and living environments.RESULTS The mean FAZ area in all eyes was 0.27 mm^(2)±0.12 mm^(2).The mean foveal thickness(MFT)in the macular cube was 227.64μm±23.51μm.Compared with girls,boys had a lager FAZ(P=0.0029).Among the different age groups,MFT(P<0.001)and FVD(P<0.0001),IVD(P<0.0001),and CVD(P=0.0050)increased with age.FAZ areas were not correlated with age(P=0.8853)or others(MFT,area).CONCLUSION OCTA can use to evaluate macular perfusion in children.Our data bridge the gap between structural OCT and perfusion density in children in high altitude.Even though these were not a longitudinal study,it may provide us with hints about retina development during puberty and clinical implications of OCTA in children. 展开更多
关键词 Optical coherence tomography-angiography Qamdo Foveal avascular zone area Vessel flow density TEENAGER
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新型冠状病毒肺炎疫情期间肺癌患者临床管理 被引量:17
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作者 徐燕 刘洪生 +1 位作者 胡克 王孟昭 《中国肺癌杂志》 CAS CSCD 北大核心 2020年第3期136-141,共6页
自2019年12月底以来,湖北省武汉市陆续发现多例新型冠状病毒肺炎(简称:新冠肺炎,2019 novel coronavirusdisease,COVID-19),并在全国范围内蔓延。随着新冠肺炎疫情的蔓延,肺癌患者的常规医疗受到影响。由于肺癌患者接受抗肿瘤治疗后免... 自2019年12月底以来,湖北省武汉市陆续发现多例新型冠状病毒肺炎(简称:新冠肺炎,2019 novel coronavirusdisease,COVID-19),并在全国范围内蔓延。随着新冠肺炎疫情的蔓延,肺癌患者的常规医疗受到影响。由于肺癌患者接受抗肿瘤治疗后免疫力低,合并感染后症状重,应是疫情防治的重点对象,肺癌患者对新冠肺炎的防范措施日益受到关注。复杂严峻的新冠肺炎疫情下,接受抗肿瘤治疗的肺癌患者如出现发热及呼吸道症状,更需要仔细地进行鉴别诊断,评估新冠肺炎感染的风险。对于肺癌患者,在新冠肺炎疫情期间,需要进行精细化和个体化的管理,最大程度地保护患者,有效防范新冠肺炎。 展开更多
关键词 肺肿瘤 患者管理 新型冠状病毒肺炎
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水凝胶的改性及其在生物医学中的 应用研究进展 被引量:2
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作者 郭振超 胡克 +3 位作者 马晓娥 周乃珍 张天柱 顾宁 《材料化学前沿》 2014年第2期32-37,共6页
水凝胶的改性是水凝胶在多方面获得应用的前提条件。本文重点综述了几类水凝胶的改性及其应用进展,包括聚乙烯醇(PVA)和明胶复合水凝胶、蛋白质水凝胶、新型智能水凝胶以及纳米水凝胶。同时指出要密切关注改性水凝胶的生物相容性、成本... 水凝胶的改性是水凝胶在多方面获得应用的前提条件。本文重点综述了几类水凝胶的改性及其应用进展,包括聚乙烯醇(PVA)和明胶复合水凝胶、蛋白质水凝胶、新型智能水凝胶以及纳米水凝胶。同时指出要密切关注改性水凝胶的生物相容性、成本价格、生物可降解性、适用范围,使更多水凝胶能走向临床,获得更广泛的应用。 展开更多
关键词 复合水凝胶 智能水凝胶 改性水凝胶 生物医学应用
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Investigating the Transport Mechanism of PM2.5 Pollution during January 2014 in Wuhan, Central China 被引量:14
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作者 Miaomiao LU Xiao TANG +9 位作者 Zifa WANG Lin WU Xueshun CHEN Shengwen LIANG hui ZHOU huangjian WU ke hu Longjiao SHEN Jia YU Jiang Zhu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第11期1217-1234,I0012-I0017,共19页
Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different f... Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different from other megacities, like Beijing. Both the growth rates and decline rates of PM2.5 concentrations in Wuhan were lower than those in Beijing, but the monthly PM2.5 value was approximately twice that in Beijing. Furthermore, the sharp increases of PM2.5 concentrations were often accompanied by strong winds. A high-precision modeling system with an online source-tagged method was established to explore the formation mechanism of five haze episodes. The long-range transport of the polluted air masses from the North China Plain (NCP) was the main factor leading to the sharp increases of PM2.5 concentrations in Wuhan, which contributed 53.4% of the monthly PM2.5 concentrations and 38.5% of polluted days. Furthermore, the change in meteorological conditions such as weakened winds and stable weather conditions led to the accumulation of air pollutants in Wuhan after the long-range transport. The contribution from Wuhan and surrounding cities to the PM2.5 concentrations was determined to be 67.4% during this period. Under the complex regional transport of pollutants from surrounding cities, the NCP, East China, and South China, the five episodes resulted in 30 haze days in Wuhan. The findings reveal important roles played by transregional and intercity transport in haze formation in Wuhan. 展开更多
关键词 HAZE POLLUTION regional transport WUHAN NORTH China PLAIN source-tagged method
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Brazeability evaluation of Ti-Zr-Cu-Ni-Co-Mo filler for vacuum brazing TiAl-based alloy 被引量:9
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作者 Li LI Xiao-qiang LI +2 位作者 ke hu Bo-lin HE hua MAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第4期754-763,共10页
Ti-47Al-2Nb-2Cr-0.15B(mole fraction,%)alloy was vacuum brazed with amorphous and crystalline Ti.25Zr-12.5Cu-12.5Ni-3.0Co-2.0Mo(mass fraction,%)filler alloys,and the melting,spreading and gap filling behaviors of the a... Ti-47Al-2Nb-2Cr-0.15B(mole fraction,%)alloy was vacuum brazed with amorphous and crystalline Ti.25Zr-12.5Cu-12.5Ni-3.0Co-2.0Mo(mass fraction,%)filler alloys,and the melting,spreading and gap filling behaviors of the amorphous and crystalline filler alloys as well as the joints brazed with them were investigated in details.Results showed that the amorphous filler alloy possessed narrower melting temperature interval,lower liquidus temperature and melting active energy compared with the crystalline filler alloy,and it also exhibited better brazeability on the surface of the Ti.47Al.2Nb.2Cr.0.15B alloy.The TiAl joints brazed with crystalline and amorphous filler alloys were composed of two interfacial reaction layers and a central brazed layer.Under the same conditions,the tensile strength of the joint brazed with the amorphous filler alloy was always higher than that with the crystalline filler alloy.The maxmium tensile strength of the joint brazed at 1273 K with the amorphous filler alloy reached 254 MPa. 展开更多
关键词 vacuum brazing Ti.47Al.2Nb.2Cr.0.15B alloy amorphous Ti-25Zr-12.5Cu-12.5Ni-3.0Co-2.0Mo filler alloy tensile strength interfacial microstructure brazeability
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Anti-tumor activity of tanshinone ⅡA in combined with cyclophosphamide against Lewis mice with lung cancer 被引量:7
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作者 Qi Li ke hu +2 位作者 Si Tang Li-Fang Xu Yu-Chuan Luo 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第11期1062-1065,共4页
Objective:To explore the anti-tumor activity of tanshinone ⅡA in combined with cyclophosphamide against Lewis mice with lung cancer and the effect on cellular immune function.Methods:Lewis tumor cells were inoculated... Objective:To explore the anti-tumor activity of tanshinone ⅡA in combined with cyclophosphamide against Lewis mice with lung cancer and the effect on cellular immune function.Methods:Lewis tumor cells were inoculated suhcutaneously into the right armpit of mice in each group(n=20) to establish Lewis lung cancer mice model.After model establishment,mice in the model group were given normal saline by lavage,qd.Mice in treatment Ⅰ group were given intraperitoneal injection of TanIIA,15 mg/kg,qd.Mice in treatment Ⅱ group were given intraperitoneal injection of CTX,25 mg/kg,qd.Mice in treatment Ⅲ group were given intraperitoneal injections of TanIIA and CTX,in which the administration method of TanIIA was the same as in treatment Ⅰ group,continuously for 2 weeks,and the dosage of CTX was the same as in treatment Ⅱ group,24 h after model establishment,every other day.Mice were sacrificed 2 weeks after establishment.The tumor tissues were collected to calculate the anti-tumor rate.Immunohistochemistry was used to detect the expressions of Bcl-2,Bax,VEGF,Angiostatin,and Endostatin.FCM was used to detect T lymphocyte subsets in spleen and liver of mice.Results:The tumor weight in treatment Ⅰ,Ⅱ,and Ⅲ groups was significantly lower than that in the model group(P<0.05).The tumor weight in treatment Ⅲ group was significantly lower than that in treatment Ⅰ and Ⅱ groups(P<0.05).The anti-tumor rate in treatment Ⅱ and Ⅲ groups was significantly higher than that in treatment Ⅰ group(P<0.05).Bcl-2 expression in the tumor tissues of treatment Ⅰ,Ⅱ,and Ⅲgroups was significantly lower than that in the model group(P<0.05),while Bax expression was significantly higher than that in the model group(P<0.05).Bcl-2 expression in the tumor tissues of treatment Ⅰ and Ⅱ groups was significantly higher than that in treatment Ⅲ group(P<0.05),while Bax expression was significantly lower than that in treatment Ⅲ group(P<0.05).CD4^+ and CD4^+/CD8^+ in treatment Ⅰ,Ⅱ,and Ⅲ groups were significantly higher than those in the model group(P<0.05).CD4^+ in treatment Ⅲ group was significantly higher than that in treatment Ⅰ and Ⅱ groups(P<0.05),while CD4^+/CD8^+ was significantly higher than that in treatment Ⅱ group(P<0.05).The comparison of CD8^+ among each group was not statistically significant(P>0.05).NK cell activity in treatment Ⅰ,Ⅱ,and Ⅲ groups was significantly higher than that in the model group(P<0.05).NK cell activity in treatment Ⅲ group was significantly higher than that in treatment Ⅰ and Ⅱ groups(P<0.05).Conclusions:TannA in combined with CTX can down regulate Bcl-2 expression in lung cancer tissues,up regulate Bax expression,inhibit the neovascularization of tumor tissues,and enhance the immunological function,with a significant anti-tumor activity. 展开更多
关键词 Lung cancer Bax Bcl-2 VEGF ANGIOSTATIN ENDOSTATIN
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