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赛沃替尼治疗MET基因突变非小细胞肺癌的药物浓度与疗效和不良反应的关系
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作者 韩森 马旭 +13 位作者 聂鋆 戴玲 胡维亨 陈筱玲 张洁 马向娟 田广明 吴頔 龙皆然 韩金娣 张自然 张攀攀 郝倩云 方健 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第3期113-117,共5页
目的:探讨药物浓度与疗效和不良反应之间的关系,了解赛沃替尼治疗MET14外显子跳跃突变晚期非小细胞肺癌患者的疗效和安全性。方法:回顾性分析2018年4月至2019年9月北京大学肿瘤医院收治的携带MET14外显子跳跃突变,并且接受赛沃替尼治疗... 目的:探讨药物浓度与疗效和不良反应之间的关系,了解赛沃替尼治疗MET14外显子跳跃突变晚期非小细胞肺癌患者的疗效和安全性。方法:回顾性分析2018年4月至2019年9月北京大学肿瘤医院收治的携带MET14外显子跳跃突变,并且接受赛沃替尼治疗的16例局部晚期或转移性非小细胞肺癌患者的临床资料及其血浆药物浓度,评估赛沃替尼治疗的疗效和安全性,分析药物浓度与疗效及不良反应的相关性。随访患者的无进展生存期(progression-free survival,PFS)和总生存期(overall survival,OS),采用Kaplan-Meier法计算中位PFS和OS。结果:16例患者中男性9例(56.3%),年龄范围51~84岁。肺癌病理类型包括:腺癌11例,肉瘤样癌5例,鳞癌1例。赛沃替尼的客观缓解率为50.0%(8/16),疾病控制率达到87.5%(14/16)。评效达到部分缓解患者和未达到者相比,赛沃替尼的药物谷浓度分别为77.2 ng/mL和146.7 ng/mL(P=0.06)。治疗中出现过2级以上不良反应的患者和仅出现过1级不良反应者,其药物谷浓度分别为116.5 ng/mL和93.2 ng/mL(P=0.59)。所有患者的中位PFS为8.5个月,中位OS为14.1个月。结论:赛沃替尼治疗MET基因突变非小细胞肺癌的效果较好,不良反应可耐受。常规用药剂量下,赛沃替尼的血浆药物谷浓度与疗效可能存在一定负相关,但药物浓度与不良反应的程度无明显相关性。 展开更多
关键词 非小细胞肺癌 MET14外显子跳跃突变 赛沃替尼 药物浓度 治疗药物监测
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一种统计特征保持的时序数据库水印方案
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作者 于烨璐 马泽华 +3 位作者 张杰 方涵 张卫明 俞能海 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第4期2-11,1,66,共12页
数据库水印是保护数据库版权最有效的方法之一。然而,传统的数据库水印有一个潜在的缺点:水印的嵌入会改变数据的分布,从而影响数据库的使用和分析。考虑到大多数分析都是基于目标数据库的统计特征,保持统计特征的一致性是确保数据库可... 数据库水印是保护数据库版权最有效的方法之一。然而,传统的数据库水印有一个潜在的缺点:水印的嵌入会改变数据的分布,从而影响数据库的使用和分析。考虑到大多数分析都是基于目标数据库的统计特征,保持统计特征的一致性是确保数据库可分析性的关键。由于统计特征分析往往是分组进行的,与传统的关系数据库相比,时序数据库(TSDBs)具有明显的时间分组特征,更具有分析价值。因此,本文提出了一种鲁棒的时序数据库水印算法,有效地保证了统计特征的一致性。基于TSDBs的时间分组特征,提出了一种基于线性回归、误差补偿和水印验证的三步水印方案RCV。根据线性回归模型和误差补偿的特性,该方案可以生成一组具有相同统计特征的数据。然后,基于验证机制对生成的数据进行验证,直到它可以传递目标的水印消息为止。与现有方法相比,该方法具有更好的鲁棒性和保持统计特征不变的能力。 展开更多
关键词 数据库水印 时序数据库 统计特征 时间分组特征
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Transcriptomic and bioinformatics analysis of the mechanism by which erythropoietin promotes recovery from traumatic brain injury in mice 被引量:1
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作者 Weilin Tan Jun Ma +9 位作者 Jiayuanyuan Fu Biying Wu Ziyu Zhu Xuekang Huang Mengran Du Chenrui Wu Ehab Balawi Qiang Zhou jie zhang Zhengbu Liao 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期171-179,共9页
Recent studies have found that erythropoietin promotes the recovery of neurological function after traumatic brain injury.However,the precise mechanism of action remains unclea r.In this study,we induced moderate trau... Recent studies have found that erythropoietin promotes the recovery of neurological function after traumatic brain injury.However,the precise mechanism of action remains unclea r.In this study,we induced moderate traumatic brain injury in mice by intrape ritoneal injection of erythro poietin for 3 consecutive days.RNA sequencing detected a total of 4065 differentially expressed RNAs,including 1059 mRNAs,92 microRNAs,799 long non-coding RNAs,and 2115circular RNAs.Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyses revealed that the coding and non-coding RNAs that were differentially expressed after traumatic brain injury and treatment with erythropoietin play roles in the axon guidance pathway,Wnt pathway,and MAPK pathway.Constructing competing endogenous RNA networks showed that regulatory relationship between the differentially expressed non-coding RNAs and mRNAs.Because the axon guidance pathway was repeatedly enriched,the expression of Wnt5a and Ephb6,key factors in the axonal guidance pathway,was assessed.Ephb6 expression decreased and Wnt5a expression increased after traumatic brain injury,and these effects were reversed by treatment with erythro poietin.These findings suggest that erythro poietin can promote recove ry of nerve function after traumatic brain injury through the axon guidance pathway. 展开更多
关键词 axon guidance bioinformatics analysis competing endogenous RNA ERYTHROPOIETIN Gene Ontology Kyoto Encyclopedia of Genes and Genomes non-coding RNA RNA sequencing transcriptomics traumatic brain injury
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Pericytes protect rats and mice from sepsis-induced injuries by maintaining vascular reactivity and barrier function:implication of miRNAs and microvesicles 被引量:1
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作者 Zi-Sen zhang Yi-Yan Liu +10 位作者 Shuang-Shuang He Dai-Qin Bao Hong-Chen Wang jie zhang Xiao-Yong Peng Jia-Tao Zang Yu Zhu Yue Wu Qing-Hui Li Tao Li Liang-Ming Liu 《Military Medical Research》 SCIE CAS CSCD 2024年第1期1-18,共18页
Background Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis.We hypothesized that pericytes,a group of pluripotent cells that maintain vascular integrity... Background Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis.We hypothesized that pericytes,a group of pluripotent cells that maintain vascular integrity and tension,are protective against sepsis via regulating vascular reactivity and permeability.Methods We conducted a series of in vivo experiments using wild-type(WT),platelet-derived growth factor receptor-β(PDGFR-β)-Cre+mT/mG transgenic mice and Tie2-Cre+Cx43^(flox/flox)mice to examine the relative contribution of pericytes in sepsis,either induced by cecal ligation and puncture(CLP)or lipopolysaccharide(LPS)challenge.In a separate set of experiments with Sprague-Dawley(SD)rats,pericytes were depleted using CP-673451,a selective PDGFR-βinhibitor,at a dosage of 40 mg/(kg·d)for 7 consecutive days.Cultured pericytes,vascular endothelial cells(VECs)and vascular smooth muscle cells(VSMCs)were used for mechanistic investigations.The effects of pericytes and pericyte-derived microvesicles(PCMVs)and candidate miRNAs on vascular reactivity and barrier function were also examined.Results CLP and LPS induced severe injury/loss of pericytes,vascular hyporeactivity and leakage(P<0.05).Transplantation with exogenous pericytes protected vascular reactivity and barrier function via microvessel colonization(P<0.05).Cx43 knockout in either pericytes or VECs reduced pericyte colonization in microvessels(P<0.05).Additionally,PCMVs transferred miR-145 and miR-132 to VSMCs and VECs,respectively,exerting a protective effect on vascular reactivity and barrier function after sepsis(P<0.05).miR-145 primarily improved the contractile response of VSMCs by activating the sphingosine kinase 2(Sphk2)/sphingosine-1-phosphate receptor(S1PR)1/phosphorylation of myosin light chain 20 pathway,whereas miR-132 effectively improved the barrier function of VECs by activating the Sphk2/S1PR2/zonula occludens-1 and vascular endothelial-cadherin pathways.Conclusions Pericytes are protective against sepsis through regulating vascular reactivity and barrier function.Possible mechanisms include both direct colonization of microvasculature and secretion of PCMVs. 展开更多
关键词 PERICYTE Vascular reactivity Vascular permeability CX43 MICROVESICLE
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Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model 被引量:1
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作者 Jun Guo Wenbo Huang +7 位作者 Guorui Feng Jinwen Bai Lirong Li Zi Wang Luyang Yu Xiaoze Wen jie zhang Wenming Feng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期491-505,共15页
The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct ... The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working conditions.Based on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were researched.Firstly,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution characteristics.The influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure area.Thirdly,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal. 展开更多
关键词 Extremely thick coal seam Fully mechanized top coal caving Support strength Support-surrounding rock interaction
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A 16-bit 18-MSPS flash-assisted SAR ADC with hybrid synchronous and asynchronous control logic 被引量:1
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作者 Junyao Ji Xinao Ji +5 位作者 Ziyu Zhou Zhichao Dai Xuhui Chen jie zhang Zheng Jiang Hong zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期3-12,共10页
This paper presents a 16-bit,18-MSPS(million samples per second)flash-assisted successive-approximation-register(SAR)analog-to-digital converter(ADC)utilizing hybrid synchronous and asynchronous(HYSAS)timing control l... This paper presents a 16-bit,18-MSPS(million samples per second)flash-assisted successive-approximation-register(SAR)analog-to-digital converter(ADC)utilizing hybrid synchronous and asynchronous(HYSAS)timing control logic based on an on-chip delay-locked loop(DLL).The HYSAS scheme can provide a longer settling time for the capacitive digital-to-analog converter(CDAC)than the synchronous and asynchronous SAR ADC.Therefore,the issue of incomplete settling or ringing in the DAC voltage for cases of either on-chip or off-chip reference voltage can be solved to a large extent.In addition,the fore-ground calibration of the CDAC’s mismatch is performed with a finite-impulse-response bandpass filter(FIR-BPF)based least-mean-square(LMS)algorithm in an off-chip FPGA(field programmable gate array).Fabricated in 40-nm CMOS process,the proto-type ADC achieves 94.02-dB spurious-free dynamic range(SFDR),and 75.98-dB signal-to-noise-and-distortion ratio(SNDR)for a 2.88-MHz input under 18-MSPS sampling rate. 展开更多
关键词 SAR ADC control logic reference ringing DAC incomplete settling
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中国蚊蝎蛉科三新种记述(长翅目)
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作者 何乐乐 张洁 +1 位作者 吴玥灵 花保祯 《Entomotaxonomia》 CSCD 2024年第2期116-125,共10页
本研究发现并描述采自中国贵州省和广东省的蚊蝎蛉属2新种和地蚊蝎蛉属1新种。其中观音山蚊蝎蛉Bittacus guanyinshanicus sp.nov.的主要鉴别特征是雄性载肛突上瓣基部膨大,中部缢缩,阳茎叶较长,侧面近纺锤形。长带蚊蝎蛉Bittacus longi... 本研究发现并描述采自中国贵州省和广东省的蚊蝎蛉属2新种和地蚊蝎蛉属1新种。其中观音山蚊蝎蛉Bittacus guanyinshanicus sp.nov.的主要鉴别特征是雄性载肛突上瓣基部膨大,中部缢缩,阳茎叶较长,侧面近纺锤形。长带蚊蝎蛉Bittacus longifasciatus sp.nov.翅面具1较大暗棕色带状斑。黑毛地蚊蝎蛉Terrobittacus nigrosetus sp.nov.具明显暗黑色背中带,雄性上生殖瓣腹缘基部密生黑色长刚毛。 展开更多
关键词 蚊蝎蛉属 地蚊蝎蛉属 分类 中国
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Monitoring seismicity in the southern Sichuan Basin using a machine learning workflow 被引量:1
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作者 Kang Wang jie zhang +2 位作者 Ji zhang zhangyu Wang Huiyu Zhu 《Earthquake Research Advances》 CSCD 2024年第1期59-66,共8页
Monitoring seismicity in real time provides significant benefits for timely earthquake warning and analyses.In this study,we propose an automatic workflow based on machine learning(ML)to monitor seismicity in the sout... Monitoring seismicity in real time provides significant benefits for timely earthquake warning and analyses.In this study,we propose an automatic workflow based on machine learning(ML)to monitor seismicity in the southern Sichuan Basin of China.This workflow includes coherent event detection,phase picking,and earthquake location using three-component data from a seismic network.By combining Phase Net,we develop an ML-based earthquake location model called Phase Loc,to conduct real-time monitoring of the local seismicity.The approach allows us to use synthetic samples covering the entire study area to train Phase Loc,addressing the problems of insufficient data samples,imbalanced data distribution,and unreliable labels when training with observed data.We apply the trained model to observed data recorded in the southern Sichuan Basin,China,between September 2018 and March 2019.The results show that the average differences in latitude,longitude,and depth are 5.7 km,6.1 km,and 2 km,respectively,compared to the reference catalog.Phase Loc combines all available phase information to make fast and reliable predictions,even if only a few phases are detected and picked.The proposed workflow may help real-time seismic monitoring in other regions as well. 展开更多
关键词 Earthquake monitoring Machine learning Local seismicity Gaussian waveform Sparse stations
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数学教学中学生创新思维能力的培养路径 被引量:1
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作者 张杰 《西北成人教育学院学报》 2024年第4期96-100,共5页
在小学数学教学中,学生对于基础知识的掌握固然重要,但学生综合素质的全面发展也不容忽视。基于这个认知,在小学数学教学中,激发学生对数学学习的兴趣,提高创造性思维能力显得尤为重要。本研究根据多年从事数学教学的经验和对学生在不... 在小学数学教学中,学生对于基础知识的掌握固然重要,但学生综合素质的全面发展也不容忽视。基于这个认知,在小学数学教学中,激发学生对数学学习的兴趣,提高创造性思维能力显得尤为重要。本研究根据多年从事数学教学的经验和对学生在不同学习阶段表现的掌握,提出如何分阶段训练学生的数学创造性思维能力和创造性思想的培养策略。 展开更多
关键词 小学数学教学 创新思维能力
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Geant4 simulation of fast-electron bremsstrahlung imaging at the HL-3 tokamak
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作者 Shi-Kui Cheng Yi-Po zhang +4 位作者 Yue-Jiang Shi jie zhang Shuai Guan Hong-Bing Xu Qiu-Lei Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期213-229,共17页
To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 keV.The application of an array-... To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 keV.The application of an array-structured detector ensures that this system can measure HXR-radiation spectra from the entire plasma cross section.Therefore,it is suitable for the study of fast-electron physics,such as radio-frequency wave current drives,fast electrons driving instabilities,and plasma disruptions in fusion research.In this study,we develop a simulation for calculating fast-electron bremsstrahlung in the HL-3 tokamak based on the Monte Carlo simulation code Geant4,in which the plasma geometry and forward scattering of fast-electron bremsstrahlung are considered.The preliminary calculation results indicate that the HXR energy deposi-tion on the detector is symmetrically distributed,even though the plasma distribution is asymmetric owing to the toroidal effect.These simulation results are helpful in constructing the relationship between the energy deposition on the detector and parameter distribution on the plasma cross section during HL-3 experiments.This is beneficial for the reconstruction of the fast-electron-distribution function and for optimizing the design of the HXR-imaging system. 展开更多
关键词 GEANT4 SIMULATION HL-3 TOKAMAK Fast-electron bremsstrahlung Hard X-ray imaging
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Plant life form determines spatiotemporal variability and climate response of plant seed rain in subtropical forests
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作者 Yuyang Xie Zehao Shen +2 位作者 Xuejing Wang Liu Yang jie zhang 《Forest Ecosystems》 SCIE CSCD 2024年第2期193-201,共9页
Spatiotemporal variation of seed rain reflects the response of plants in terms of their reproductive strategy to environmental gradients.In this study,we collected seeds from four sites in the Dalaoling Nature Reserve... Spatiotemporal variation of seed rain reflects the response of plants in terms of their reproductive strategy to environmental gradients.In this study,we collected seeds from four sites in the Dalaoling Nature Reserve,Hubei Province,China,between 2011 and 2014,measured seed output and seed mass as seed rain traits,and compared their interannual and elevational variation.Then,we ran phylogenetic generalized mixed linear models(PGLMMs) to explore the effects of temperature and precipitation as well as interspecific differences on seed rain,and fitted the best regression models for seed rain vs.weather of canopy and understory species.The results showed no correlation between values of seed output and seed mass.However,the variation of the two traits showed significantly positive correlation.Seed output of canopy species generally decreased with increasing elevation,and showed significant interannual difference;however,seed output of understory species and seed mass for both canopy and understory species did not show consistency tends along elevational or in interannual variation.Seed output was significantly affected by temperature and precipitation,while seed mass mainly varied due to interspecific differences.Weather explained more the variation of the seed output of canopy species than that of understory species,with R^(2) values of 43.0%and 29.9%,respectively.These results suggested that canopy plants contributed more to the reproductive dynamics of the whole communities,and the canopy's buffer effect on the underground weakened the response of understory plants to weather variation in terms of their reproductive strategy. 展开更多
关键词 Seed rain Seed output Seed mass ELEVATION Interannual variation Lifeform
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Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids
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作者 Li-Li Yang Ze-Yu Liu +3 位作者 Shi-bo Wang Xian-Bo He Guan-Cheng Jiang jie zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期551-566,共16页
With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to r... With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore instability.In this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite partly.The suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of 2.The viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same density.Through multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of WBDFs.The sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was 0.2603.Therefore,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection capacity.This work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs. 展开更多
关键词 Drilling fluids Weighting materials Filtration control Reservoir protection Stability property
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NIR-triggered on-site NO/ROS/RNS nanoreactor:Cascade-amplified photodynamic/photothermal therapy with local and systemic immune responses activation
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作者 Ziqing Xu Yakun Kang +9 位作者 jie zhang Jiajia Tang Hanyao Sun Yang Li Doudou He Xuan Sha Yuxia Tang Ziyi Fu Feiyun Wu Shouju Wang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第6期58-73,共16页
Photothermal and photodynamic therapies(PTT/PDT)hold promise for localized tumor treatment,yet their full potential is hampered by limitations such as the hypoxic tumor microenvironment and inadequate systemic immune ... Photothermal and photodynamic therapies(PTT/PDT)hold promise for localized tumor treatment,yet their full potential is hampered by limitations such as the hypoxic tumor microenvironment and inadequate systemic immune activation.Addressing these challenges,we present a novel near-infrared(NIR)-triggered RNS nanoreactor(PBNO-Ce6)to amplify the photodynamic and photothermal therapy efficacy against triple-negative breast cancer(TNBC).The designed PBNOCe6 combines sodium nitroprusside-doped Prussian Blue nanoparticles with Chlorin e6 to enable on-site RNS production through NIR-induced concurrent NO release and ROS generation.This not only enhances tumor cell eradication but also potentiates local and systemic antitumor immune responses,protecting mice from tumor rechallenge.Our in vivo evaluations revealed that treatment with PBNO-Ce6 leads to a remarkable 2.7-fold increase in cytotoxic T lymphocytes and a 62%decrease in regulatory T cells in comparison to the control PB-Ce6(Prussian Blue nanoparticles loaded with Chlorin e6),marking a substantial improvement over traditional PTT/PDT.As such,the PBNO-Ce6 nanoreactor represents a transformative approach for improving outcomes in TNBC and potentially other malignancies affected by similar barriers. 展开更多
关键词 photothermal therapy photodynamic therapy nitric oxide reactive nitrogen species triple-negative breast cancer immune response NANOREACTOR
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Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network
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作者 Ning zhang Junfang YANG +2 位作者 Shanwei LIU Yi MA jie zhang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期728-743,共16页
The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill pollution.The selection of characteristic bands with strong separability helps to reali... The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill pollution.The selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency monitoring.At the same time,the combination of spectral and spatial features can improve the accuracy of oil spill monitoring.Two ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong separability.In addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its emulsions.Compared with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running time.Moreover,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in 2010.This study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit. 展开更多
关键词 hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)
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Pore structure and oxygen content design of amorphous carbon toward a durable anode for potassium/sodium-ion batteries
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作者 Xiaodong Shi Chuancong Zhou +7 位作者 Yuxin Gao Jinlin Yang Yu Xie Suyang Feng jie zhang Jing Li Xinlong Tian Hui zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期184-194,共11页
Both sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)are considered as promising candidates in grid-level energy storage devices.Unfortunately,the larger ionic radii of K+and Na+induce poor diffusion kineti... Both sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)are considered as promising candidates in grid-level energy storage devices.Unfortunately,the larger ionic radii of K+and Na+induce poor diffusion kinetics and cycling stability of carbon anode materials.Pore structure regulation is an ideal strategy to promote the diffusion kinetics and cyclic stability of carbon materials by facilitating electrolyte infiltration,increasing the transport channels,and alleviating the volume change.However,traditional pore-forming agent-assisted methods considerably increase the difficulty of synthesis and limit practical applications of porous carbon materials.Herein,porous carbon materials(Ca-PC/Na-PC/K-PC)with different pore structures have been prepared with gluconates as the precursors,and the amorphous structure,abundant micropores,and oxygen-doping active sites endow the Ca-PC anode with excellent potassium and sodium storage performance.For PIBs,the capacitive contribution ratio of Ca-PC is 82%at 5.0 mV s^(-1) due to the introduction of micropores and high oxygen-doping content,while a high reversible capacity of 121.4 mAh g^(-1) can be reached at 5 A g^(-1) after 2000 cycles.For SIBs,stable sodium storage capacity of 101.4 mAh g^(-1) can be achieved at 2 A g^(-1) after 8000 cycles with a very low decay rate of 0.65%for per cycle.This work may provide an avenue for the application of porous carbon materials in the energy storage field. 展开更多
关键词 oxygen doping pore structure porous carbon potassium-ion batteries sodium-ion batteries
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Efficient adsorption separation of methane from C_(2)-C_(3) hydrocarbons in a Co(Ⅱ)-nodes metal-organic framework
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作者 jie zhang Xingzhe Guo +6 位作者 Bing Lin Guangzu Xiong Hanshuang Wang Min zhang Liwen Fan Bingwen Li Shuisheng Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期192-198,共7页
Methane(CH_(4))as a substitute for other mineral fuels plays a crucial role in reducing energy consumption and preventing environmental pollution.The present study employs a solvothermal method to fabricate a porous f... Methane(CH_(4))as a substitute for other mineral fuels plays a crucial role in reducing energy consumption and preventing environmental pollution.The present study employs a solvothermal method to fabricate a porous framework Co-metal-organic framework(Co-MOF)containing two distinct secondary building units(SBUs):an anionic[Co_(2)(μ_(2)-OH)(COO)_(4)(H_(2)O)]and a neutral[CoN_(2)(COO)_(2)].Notably,within the anionic SBUs,the coordinated water molecules induce the generation of divergent unsaturated Co(Ⅱ)centers in the unidirectional porous channels,thereby creating open metal sites.The adsorption performance of Co-MOF towards pure component gases was systematically investigated.The results demonstrated that Co-MOF exhibits superior adsorption capacity for C_(2)-C_(3) hydrocarbons compared to CH_(4),which offers the potential for efficient adsorption and separation of CH_(4) from C_(2)-C_(3) hydrocarbons.The gas selectivity separation ratios of Co-MOF for C_(2)H_(6)/CH_(4) and C_(3)H_8/CH_(4) were calculated using the ideal adsorbed solution theory method at 273/298 K and 0.1 MPa.The results revealed that Co-MOF achieved remarkable equilibrium separation selectivity for CH_(4) and C_(2)-C_(3) hydrocarbon gases among non-modified MOFs,signifying the potential of the synthesized Co-MOF for efficient recovery and purification of CH_(4) from C_(2)-C_(3) hydrocarbons.Breakthrough experiments further demonstrate the ability of Co-MOF to purify methane from C_(2)-C_(3) hydrocarbons in practical gas separation scenarios.Additionally,molecular simulation calculations further substantiate the propensity of anionic SBUs to interact with C_(2)-C_(3) hydrocarbon compounds.This study provides a novel paradigm for the development of porous MOF materials in the application of gas mixture separation. 展开更多
关键词 Co-MOF Separation hydrocarbons Dynamic breakthrough curves Molecular simulations adsorbent Monte Carlo simulation
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Calcium carbonate promotes the formation and stability of soil macroaggregates in mining areas of China
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作者 Junyu Xie Jianyong Gao +7 位作者 Hanbing Cao Jiahui Li Xiang Wang jie zhang Huisheng Meng Jianping Hong Tingliang Li Minggang Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1034-1047,共14页
We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to p... We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to provide a theoretical basis for rapid reclamation of soil fertility in the subsidence area of coal mines in Shanxi Province,China.In this study,soil samples of 0–20 cm depth were collected from four fertilization treatments of a longterm experiment started in 2008:no fertilizer (CK),inorganic fertilizer (NPK),chicken manure compost (M),and50%inorganic fertilizer plus 50%chicken manure compost (MNPK).The concentrations of cementing agents and changes in soil aggregate size distribution and stability were analysed.The results showed that the formation of>2 mm aggregates,the aggregate mean weight diameter (MWD),and the proportion of>0.25 mm water-stable aggregates (WR_(0.25)) increased significantly after 6 and 11 years of reclamation.The concentration of organic cementing agents tended to increase with reclamation time,whereas free iron oxide (Fed) and free aluminium oxide(Ald) concentrations initially increased but then decreased.In general,the MNPK treatment signi?cantly increased the concentrations of organic cementing agents and CaCO_(3),and CaCO_(3) increased by 60.4%at 11 years after reclamation.Additionally,CaCO_(3) had the greatest effect on the stability of aggregates,promoting the formation of>0.25 mm aggregates and accounting for 54.4%of the variance in the proportion and stability of the aggregates.It was concluded that long-term reclamation is bene?cial for improving soil structure.The MNPK treatment was the most effective measure for increasing maize grain yield and concentration of organic cementing agents and CaCO_(3). 展开更多
关键词 reclamation time manure combined with inorganic fertilizer soil aggregate stability cementing agents CaCO_(3)
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Optimized online filter stack spectrometer for ultrashort X-ray pulses
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作者 Jia-Xing Wen Ge Ma +17 位作者 Ming-Hai Yu Yu-Chi Wu Yong-Hong Yan Shao-Yi Wang Huai-Zhong Gao Lu-Shan Wang Yu-Gang Zhou Qiang Li Yue Yang Fang Tan Xiao-Hui zhang jie zhang Wen-Bo Mo Jing-Qin Su Wei-Min Zhou Yu-Qiu Gu Ming Zeng Zong-Qing Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期85-98,共14页
Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for c... Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for characterizing electron dynamics and applications.In this study,scintillators and silicon PIN(P-type–intrinsic-N-type semiconductor)diodes were used to construct a wideband online filter stack spectrometer.The X-ray sensor and filter arrangement was optimized using a genetic algorithm to minimize the condition number of the response matrix.Consequently,the unfolding error was significantly reduced based on numerical experiments.The detector responses were quantitatively calibrated by irradiating the scintillator and PIN diode with various nuclides and comparing the measuredγ-ray peaks.A prototype 15-channel spectrometer was developed by integrating an X-ray detector with front-and back-end electronics.The prototype spectrometer could record X-ray pulse signals at a repetition rate of 1 kHz.Furthermore,an optimized spectrometer was employed to record the real-time spectra of laser-driven bremsstrahlung sources.This optimized spectrometer offers a compact solution for spectrum diagnostics of ultrashort X-ray pulses,exhibiting improved accuracy in terms of spectrum measurements and repetition rates,and could be widely used in next-generation high-repetition-rate high-power laser facilities. 展开更多
关键词 Filter stack spectrometer Laser plasma diagnostics X-ray diagnostics Scintillator PIN diode
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Data-driven prediction of dimensionless quantities for semi-infinite target penetration by integrating machine-learning and feature selection methods
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作者 Qingqing Chen Xinyu zhang +2 位作者 Zhiyong Wang jie zhang Zhihua Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期105-124,共20页
This study employs a data-driven methodology that embeds the principle of dimensional invariance into an artificial neural network to automatically identify dominant dimensionless quantities in the penetration of rod ... This study employs a data-driven methodology that embeds the principle of dimensional invariance into an artificial neural network to automatically identify dominant dimensionless quantities in the penetration of rod projectiles into semi-infinite metal targets from experimental measurements.The derived mathematical expressions of dimensionless quantities are simplified by the examination of the exponent matrix and coupling relationships between feature variables.As a physics-based dimension reduction methodology,this way reduces high-dimensional parameter spaces to descriptions involving only a few physically interpretable dimensionless quantities in penetrating cases.Then the relative importance of various dimensionless feature variables on the penetration efficiencies for four impacting conditions is evaluated through feature selection engineering.The results indicate that the selected critical dimensionless feature variables by this synergistic method,without referring to the complex theoretical equations and aiding in the detailed knowledge of penetration mechanics,are in accordance with those reported in the reference.Lastly,the determined dimensionless quantities can be efficiently applied to conduct semi-empirical analysis for the specific penetrating case,and the reliability of regression functions is validated. 展开更多
关键词 Data-driven dimensional analysis PENETRATION Semi-infinite metal target Dimensionless numbers Feature selection
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Hybrid response surface method for system reliability analysis of pilereinforced slopes
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作者 Xiangrui Duan jie zhang +2 位作者 Leilei Liu Jinzheng Hu Yadong Xue 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3395-3406,共12页
To consider the complex soil-structure interaction in a pile-slope system,it is necessary to analyze the performance of pile-slope systems based on a three-dimensional(3D)numerical model.Reliability analysis of a pile... To consider the complex soil-structure interaction in a pile-slope system,it is necessary to analyze the performance of pile-slope systems based on a three-dimensional(3D)numerical model.Reliability analysis of a pile-slope system based on 3D numerical modeling is very challenging because it is computationally expensive and the performance function of the pile failure mode is only defined in the safe domain of soil stability.In this paper,an efficient hybrid response surface method is suggested to study the system reliability of pile-reinforced slopes,where the support vector machine and the Kriging model are used to approximate performance functions of soil failure and pile failure,respectively.The versatility of the suggested method is illustrated in detail with an example.For the example examined in this paper,it is found that the pile failure can significantly contribute to system failure,and the reinforcement ratio can effectively reduce the probability of pile failure.There exists a critical reinforcement ratio beyond which the system failure probability is not sensitive to the reinforcement ratio.The pile spacing affects both the probabilities of soil failure and pile failure of the pile-reinforced slope.There exists an optimal location and an optimal length for the stabilizing piles. 展开更多
关键词 SLOPE PILES System reliability Support vector machine Ordinary kriging
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