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Intestinal Microbial Community Differs between Acute Pancreatitis Patients and Healthy Volunteers 被引量:27
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作者 ZHANG Xi Mei ZHANG Zheng Yu +3 位作者 ZHANG Chen Huan WU Jing WANG You Xin ZHANG Guo Xin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第1期81-86,共6页
A case control study including 45 acute pancreatitis and 44 healthy volunteers was performed to investigate the association between intestinal microbial community and acute pancreatitis. High-throughput 16S r RNA gene... A case control study including 45 acute pancreatitis and 44 healthy volunteers was performed to investigate the association between intestinal microbial community and acute pancreatitis. High-throughput 16S r RNA gene amplicon sequencing was used to profile the microbiological composition of the samples. In total, 27 microbial phyla were detected and the samples of pancreatitis patients contained fewer phyla. Samples from acute pancreatitis patients contained more Bacteroidetes and Proteobacteria and fewer Firmicutes and Actinobacteria than those from healthy volunteers. PCo A analyses distinguished the fecal microbial communities of acute pancreatitis patients from those of healthy volunteers. The intestinal microbes of acute pancreatitis patients are different from those of healthy volunteers. Modulation of the intestinal microbiome may serve as an alternative strategy for treating acute pancreatitis. 展开更多
关键词 Intestinal Microbial Community differs Acute Pancreatitis Patients
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Grassland-type ecosystem stability in China differs under the influence of drought and wet events
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作者 CAO Wenyu BAI Jianjun YU Leshan 《Journal of Arid Land》 SCIE CSCD 2024年第5期615-631,共17页
Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a m... Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and intensities.China's grassland ecosystem includes most grassland types and is a good choice for studying this issue.This study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance. 展开更多
关键词 grassland ecosystem stability resistance RESILIENCE different climate types drought climate event wet climate event
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Cell therapy rejuvenates the neuroglial-vascular unit
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作者 Bandy Chen 《Neural Regeneration Research》 2026年第4期1542-1543,共2页
The rise of the aging population parallels the rapidly increasing cases of neurological disorders. This puts pressure on scientists and physicians to find novel methods that can prevent and treat neurodegeneration. Th... The rise of the aging population parallels the rapidly increasing cases of neurological disorders. This puts pressure on scientists and physicians to find novel methods that can prevent and treat neurodegeneration. The brain is made up of a complex network of different cell types that work in tandem to maintain systemic homeostasis. 展开更多
关键词 maintain systemic homeostasis prevent treat neurodegeneration cell therapy neurological disorders neuroglial vascular unit network different cell types NEURODEGENERATION aging population
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One Country,Two Viewpoints The Japanese emperor's remorse over non-Japanese victims of World WarⅡdiffers sharply from the prime minister's persistent Yasukuni Shrine visits
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作者 LI LI 《Beijing Review》 2006年第4期12-13,共2页
Against the backdrop of all-time low relations with Asian neighbors, Japan's Emperor Akihito used the occasions of his annual birthday press conference and New Year greeting to talk to his nation about wartime his... Against the backdrop of all-time low relations with Asian neighbors, Japan's Emperor Akihito used the occasions of his annual birthday press conference and New Year greeting to talk to his nation about wartime history. The fact that he rarely addresses 展开更多
关键词 One Country Two Viewpoints The Japanese emperor’s remorse over non-Japanese victims of World War differs sharply from the prime minister’s persistent Yasukuni Shrine visits World
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基于DEMATEL和TOPSIS的低空安防系统方案多属性评价方法 被引量:1
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作者 施玮 吴坚 《科学技术与工程》 北大核心 2025年第14期6109-6117,共9页
针对低空经济发展涉及的安全管理问题,在总结低空经济相关技术路线原理及落地方案的运行经验,分析低空安防普适性的4个建设方案:雷达与通感一体技术融合方案、广播式自动相关监视技术方案、远程识别技术方案和基于TDOA(time difference ... 针对低空经济发展涉及的安全管理问题,在总结低空经济相关技术路线原理及落地方案的运行经验,分析低空安防普适性的4个建设方案:雷达与通感一体技术融合方案、广播式自动相关监视技术方案、远程识别技术方案和基于TDOA(time difference of arrival)无线电技术的多源融合方案的基础上,构建无人飞行器探测技术评价指标体系,并建立了一种基于决策试验评估实验室(decision-making trial and evaluation laboratory, DEMATEL)和优劣解距离法(technique for order preference by similarity to an ideal solution, TOPSIS)的多属性评价方法。结果发现,以TDOA为基础的多源融合方案是构建城市低空安防体系的有效路径和普适性方案。研究表明,低空安防体系的建设是一个系统性工程,需要政府、企业和社会各方的共同努力,在技术、数据、运营等多个层面进行整合,以适应未来低空经济的发展需求。 展开更多
关键词 低空经济 低空安防系统 多属性评价方法 TDOA(time difference of arrival)技术 无人机管控
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Variations in quantifying patient reported outcome measures to estimate treatment effect 被引量:1
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作者 Sathish Muthu Srujun Vadranapu 《World Journal of Methodology》 2025年第2期44-53,共10页
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ... In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice. 展开更多
关键词 Patient-reported outcome measures Treatment effect Minimal clinical important difference Patient-accepted symptom state Minimum detectable change ORTHOPEDICS
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Kinesin family member 14 expression and its clinical implications in colorectal cancer 被引量:2
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作者 Kai Qin Jia-Yuan Luo +12 位作者 Da-Tong Zeng Wan-Ying Huang Bin Li Qi Li Yan-Ting Zhan Rong-Quan He Wei-Jian Huang Gang Chen Zu-Yuan Chen Bang-Teng Chi Yu-Xing Tang Rui-Xue Tang Hui Li 《World Journal of Gastrointestinal Oncology》 2025年第3期299-321,共23页
BACKGROUND Colorectal cancer(CRC)is the third most common cancer globally,causing over 900000 deaths annually.Risk factors include aging,diet,obesity,sedentary lifestyle,tobacco use,genetic predisposition,and inflamma... BACKGROUND Colorectal cancer(CRC)is the third most common cancer globally,causing over 900000 deaths annually.Risk factors include aging,diet,obesity,sedentary lifestyle,tobacco use,genetic predisposition,and inflammatory bowel disease.Despite current treatments,survival rates for advanced CRC remain low,highlighting the need for better therapeutic strategies.AIM To evaluate both the clinical significance and the pathological implications of the Kinesin family member 14(KIF14)expression within CRC specimens.Additionally,this study aims to investigate the interaction between nitidine chloride(NC)and KIF14,considering their potential as therapeutic targets.METHODS The expression of the KIF14 protein in CRC was analyzed using immunohistochemical staining.The integration of multicenter high-throughput data facilitated the calculation of the standardized mean difference(SMD)for KIF14 mRNA levels.The assessment of clinical and pathological impact was enhanced by analyzing combined receiver operating characteristic curves,along with measures of sensitivity,specificity,and likelihood ratios.Additionally,clustered regularly interspaced short palindromic repeats knockout screening for cell growth and single-cell sequencing were employed to validate the significance of KIF14 expression in CRC.Survival analysis established the prognostic value of KIF14 in CRC.The molecular mechanism of NC against CRC was elucidated through whole-genome sequencing and enrichment analysis,and molecular docking was utilized to explore the targeting affinity between NC and KIF14.RESULTS KIF14 was highly expressed in 208 CRC patients.Data from 17 platforms involving 2436 CRC samples and 1320 noncancerous colorectal tissue controls indicated that KIF14 expression was significantly higher in CRC samples,with an SMD of 1.92(95%CI:1.49-2.35).The area under the curve was 0.94(95%CI:0.92-0.96),with a sensitivity of 0.85(95%CI:0.78-0.90)and a specificity of 0.90(95%CI:0.85-0.93).The positive and negative likelihood ratios were 8.38(95%CI:5.39-13.02)and 0.17(95%CI:0.11-0.26),respectively.At the single-cell level,significant overexpression of KIF14 was observed in CRC cells(P<0.001),with 35 CRC cell lines dependent on KIF14 for growth.The K-M plots demonstrated that KIF14 possesses prognostic value in CRC patients within the GSE71187 and GSE103679 datasets(P<0.05).Binding energy calculations indicated that KIF14 is a potential target for NC(binding energy:10.3 kcal/mol).CONCLUSION KIF14 promotes the growth of CRC cells and acts as an oncogenic factor,potentially serving as a therapeutic target for NC in the treatment of CRC. 展开更多
关键词 Colorectal cancer Kinesin family member 14 Nitidine chloride Molecular docking Standardized mean difference
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Role and mechanisms of histone methylation in osteogenic/odontogenic differentiation of dental mesenchymal stem cells 被引量:2
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作者 Meijun Hu Zhipeng Fan 《International Journal of Oral Science》 2025年第3期341-360,共20页
Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differen... Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differentiation potential and self-renewal ability.The cellular microenvironment regulates the fate of stem cells and can be modified using various optimization techniques.These methods can influence the cellular microenvironment,activate disparate signaling pathways,and induce different biological effects.“Epigenetic regulation”refers to the process of influencing gene expression and regulating cell fate without altering DNA sequences,such as histone methylation.Histone methylation modifications regulate pivotal transcription factors governing DMSCs differentiation into osteo-/odontogenic lineages.The most important sites of histone methylation in tooth organization were found to be H3K4,H3K9,and H3K27.Histone methylation affects gene expression and regulates stem cell differentiation by maintaining a delicate balance between major trimethylation sites,generating distinct chromatin structures associated with specific downstream transcriptional states.Several crucial signaling pathways associated with osteogenic differentiation are susceptible to modulation via histone methylation modifications.A deeper understanding of the regulatory mechanisms governing histone methylation modifications in osteo-/odontogenic differentiation and immune-inflammatory responses of DMSCs will facilitate further investigation of the epigenetic regulation of histone methylation in DMSC-mediated tissue regeneration and inflammation.Here is a concise overview of the pivotal functions of epigenetic histone methylation at H3K4,H3K9,and H3K27 in the regulation of osteo-/odontogenic differentiation and renewal of DMSCs in both non-inflammatory and inflammatory microenvironments.This review summarizes the current research on these processes in the context of tissue regeneration and therapeutic interventions. 展开更多
关键词 tooth development stem cells tissue engineering influence cellular microenvironmentactivate disparate signaling pathwaysand induce different biological effec regenerative medicine cellular microenvironment dental mesenchymal stem cells dmscs
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Deformation Monitoring of the Embankments Using Multitemporal InSAR:a Case Study of the Kangshan Embankment 被引量:1
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作者 XIONG Jiacheng HE Xiufeng +2 位作者 Alfred STEIN YU Juanjuan CHANG Ling 《Journal of Geodesy and Geoinformation Science》 2025年第1期12-29,共18页
River embankments are designed to defend against floods over coastal and riparian areas.It is important to early detect unexpected damages on embankments before they exacerbate.To continuously monitor the stability of... River embankments are designed to defend against floods over coastal and riparian areas.It is important to early detect unexpected damages on embankments before they exacerbate.To continuously monitor the stability of the embankments and efficiently recognize such potential damages,this study takes SAR(Synthetic Aperture Radar)derived deformation as an indicator of the embankment instability,and customizes a multi-temporal InSAR(Interferometric SAR)approach-small baseline subset.Specifically,during InSAR processing,we apply a two-step amplitude difference dispersion threshold method to extract InSAR measurement points,thus improving the point density within the embankment.We applied this method to the Kangshan Embankment(KE)using 147 Sentinel-1 acquired between 2017 and 2021.We categorized KE into Waterside Slope(WS),Embankment Top(ET),and Landside Slope(LS)using InSAR height estimation.Given the dominance of downslope movement,we developed a projection matrix from InSAR-derived deformation in the satellite line-of-sight direction onto WS and LS.The study shows that KE was generally stable during the five-year period,while WS,ET,and LS experienced different deformation processes.For instance,seasonal variation was observed from the deformation time series,especially between every April and November.We applied the principal component analysis to the time-series displacement and analyzed the results in conjunction with the rainfall data of Kangshan Township.It showed that deformation due to rainfall equals 80.93%,81.30%,and 82.46%of the total deformation for WS,ET,and LS,respectively,indicating that rainfall is one of the environmental driving factors affecting the deformations.We conclude that the proposed methodology is suited for systematic embankment monitoring and identifies major driving forces. 展开更多
关键词 EMBANKMENT amplitude difference dispersion slope deformation INSAR Sentinel-1
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Vocal characteristics of distress and reproductive vocalizations in North American wapiti 被引量:1
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作者 Cora Anne Romanow Tobias Riede Susan Lingle 《Current Zoology》 2025年第5期545-559,共15页
Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evi... Variation in the vocal behavior of nonhuman vertebrates includes graded transitions and more dramatic changes.Wapiti males produce a reproductive bugle that has a fundamental frequency that surpasses 2,000 Hz with evidence of biphonation and other nonlinear phenomena.Here,we analyze the acoustic structure of captive wapiti vocalizations to compare the male bugle with 3 categories of distress vocalizations:neonate distress(capture)calls,calf isolation calls,and adult female isolation calls.These 4 high-arousal call categories serve a common general function in recruiting conspecifics but occur in different behavioral contexts(capture,isolation,reproduction).Our goal was to distinguish characteristics that vary in graded steps that may correspond to an animal’s age or size from characteristics that are unique to the bugle.Characteristics of the high and loud fundamental(G0)varied in an age/size-graded manner with a decrease in minimum G0,an increase in the maximum and range of G0,with no evidence of sex differences.The nonlinear phenomena of deterministic chaos,biphonation,and frequency jumps were present in all 4 call categories and became more common from the distress vocalizations of neonates to calves to adult females to the male bugle.Two temporal characteristics sharply distinguished the bugle from the 3 categories of distress vocalizations:these included a prolonged call duration and a maximum G0 that occurred much later in the call for the bugle than for distress vocalizations.Our results suggest that distress vocalizations of different age groups and the reproductive bugle of wapiti share a high G0,with age/size-graded changes in G0 and nonlinear phenomena,but differ sharply in temporal characteristics. 展开更多
关键词 age and sex differences BIOACOUSTICS CERVUS distress vocalizations elk fundamental frequency nonlinear phenomena ONTOGENY production reproduction
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Deep phenotyping of testosterone-prompted fibrosis in arrhythmogenic right ventricular cardiomyopathy using iPSC-derived engineered cardiac spheroids 被引量:1
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作者 Hongyi Cheng Xinrui Wang +10 位作者 Sichong Qian Yike Zhang Jincheng Jiao Bingyu Zheng Yue Zhu Hua Xu Jia Song Feng Zhang Xiaohong Jiang Chang Cui Minglong Chen 《Bio-Design and Manufacturing》 2025年第1期20-35,I0002-I0012,共27页
Arrhythmogenic right ventricular cardiomyopathy(ARVC)is a progressive disease characterized by adipose and fibrous replacement of the myocardium.While elevated testosterone levels have been implicated in the pathologi... Arrhythmogenic right ventricular cardiomyopathy(ARVC)is a progressive disease characterized by adipose and fibrous replacement of the myocardium.While elevated testosterone levels have been implicated in the pathological process of ARVC,its exact contribution to cardiac fibrosis in ARVC remains unclear.In this study,we analyzed the potential contribution of gender-based differences on the distribution of the low-voltage area in an ARVC cohort undergoing an electrophysiological study,which was indicated by feature selection.Additionally,we established engineered cardiac spheroid models in vitro using patient-specific induced pluripotent stem cell(iPSC)-derived cardiomyocytes(iPSC-CMs)and iPSC-derived cardiac fibroblasts(icFBs).We elucidated the pathogenicity of abnormal splicing in the plakophilin-2(PKP2)gene caused by an intronic mutation.Additionally,pathogenic validation of the desmoglein-2(DSG2)point mutation further confirms the reliability of the models.Moreover,testosterone exacerbated the DNA damage in the mutated cardiomyocytes and further activated myofibroblasts in a chain reaction.In conclusion,we designed and constructed an in vitro three-dimensionally-engineered cardiac spheroid model of ARVC based on clinical findings and provided direct evidence of the fibrotic role of testosterone in ARVC. 展开更多
关键词 Arrhythmogenic right ventricular cardiomyopathy(ARVC) Gender difference Cardiac spheroids Testoste-rone FIBROSIS
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High expression of stearoyl-coenzyme A desaturase in colorectal cancer oncogenic functions and its potential as a therapeutic target 被引量:1
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作者 Xiao-Wei Wang Wan-Ying Huang +12 位作者 Kai Qin Da-Tong Zeng Zu-Yuan Chen Bang-Teng Chi Yu-Xing Tang Qi Li Bin Li Dong-Ming Li Rong-Quan He Wei-Jian Huang Gang Chen Rui-Xue Tang Zhen-Bo Feng 《World Journal of Gastrointestinal Surgery》 2025年第2期247-264,共18页
BACKGROUND The stearoyl-coenzyme A desaturase(SCD)gene influences colorectal cancer(CRC)pathogenesis,with its expression linked to tumor cell survival and resistance,necessitating further investigation into its role i... BACKGROUND The stearoyl-coenzyme A desaturase(SCD)gene influences colorectal cancer(CRC)pathogenesis,with its expression linked to tumor cell survival and resistance,necessitating further investigation into its role in CRC.AIM To explore the clinical and pathological significance of SCD expression in CRC tissues and to evaluate the affinity between nitidine chloride(NC)and SCD as a target.METHODS Multi-center high-throughput data related to CRC were integrated to calculate the standardized mean difference of SCD mRNA expression levels.Immunohistochemical staining results,Clustered Regularly Interspaced Short Palindromic Repeats knockout screening results of cell growth,and single-cell sequencing were employed to verify the significance of SCD expression in CRC.The clinical and pathological significance of SCD was assessed using pooled receiver operating characteristic curves,sensitivity,specificity,and likelihood ratios.The molecular mechanism of NC against CRC was clarified using the SwissTarget Prediction and functional enrichment,and molecular docking techniques were utilized to explore the targeting affinity between NC and SCD.RESULTS Data from 18 platforms,including 2482 CRC samples and 1334 non-cancerous colorectal tissue controls.SCD expression was significantly upregulated in CRC,with a standardized mean difference of 2.05[95%confidence interval(CI):1.69-2.41].The area under the pooled receiver operating characteristic curve was 0.95(95%CI:0.92-0.96),with a sensitivity of 0.86(95%CI:0.81-0.90)and a specificity of 0.90(95%CI:0.87-0.93).Positive and negative likelihood ratios were 9.02(95%CI:6.49-12.51)and 0.15(95%CI:0.10-0.22),respectively.High SCD protein expression was noted in 208 CRC patients,significantly associated with vascular invasion(P<0.001).At the singlecell level,SCD was significantly overexpressed in CRC cells(P<0.001).A total of 33 CRC cell lines depended on SCD for growth.The potential mechanism of NC against CRC might involve modulation of the cell cycle,positioning SCD as a potential target for NC.CONCLUSION SCD promotes CRC cell growth and thus acts as an oncogenic factor,making it a potential therapeutic target for NC in CRC treatment. 展开更多
关键词 Colorectal cancer Stearoyl-coenzyme A desaturase Nitidine chloride Molecular docking Standardized mean difference
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Quasi-visualizable detection of deep sub-wavelength defects in patterned wafers by breaking the optical form birefringence 被引量:1
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作者 Jiamin Liu Jinlong Zhu +8 位作者 Zhe Yu Xianrui Feng Zedi Li Lei Zhong Jinsong Zhang Honggang Gu Xiuguo Chen Hao Jiang Shiyuan Liu 《International Journal of Extreme Manufacturing》 2025年第1期623-639,共17页
In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and... In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and yields of chips.With the critical dimensions of IC nanostructures continuing to shrink,directly imaging or classifying deep-subwavelength defects by bright-field microscopy is challenging due to the well-known diffraction barrier,the weak scattering effect,and the faint correlation between the scattering cross-section and the defect morphology.Herein,we propose an optical far-field inspection method based on the form-birefringence scattering imaging of the defective nanostructure,which can identify and classify various defects without requiring optical super-resolution.The technique is built upon the principle of breaking the optical form birefringence of the original periodic nanostructures by the defect perturbation under the anisotropic illumination modes,such as the orthogonally polarized plane waves,then combined with the high-order difference of far-field images.We validated the feasibility and effectiveness of the proposed method in detecting deep subwavelength defects through rigid vector imaging modeling and optical detection experiments of various defective nanostructures based on polarization microscopy.On this basis,an intelligent classification algorithm for typical patterned defects based on a dual-channel AlexNet neural network has been proposed,stabilizing the classification accuracy ofλ/16-sized defects with highly similar features at more than 90%.The strong classification capability of the two-channel network on typical patterned defects can be attributed to the high-order difference image and its transverse gradient being used as the network’s input,which highlights the polarization modulation difference between different patterned defects more significantly than conventional bright-field microscopy results.This work will provide a new but easy-to-operate method for detecting and classifying deep-subwavelength defects in patterned wafers or photomasks,which thus endows current online inspection equipment with more missions in advanced IC manufacturing. 展开更多
关键词 defect inspection form birefringence breaking high order difference anisotropic illumination modes deep-subwavelength sensitivity defect classification
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Numerical Methods for Boundary Value Problems in Variable Coefficient Ordinary Differential Equations 被引量:1
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作者 ZHAO Ting-ting CAI Wei-yun 《Chinese Quarterly Journal of Mathematics》 2025年第3期295-303,共9页
In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error... In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error between the numerical solution and the exact solution is obtained,and then compared with the error formed by the difference method,it is concluded that the Lagrange interpolation method is more effective in solving the variable coefficient ordinary differential equation. 展开更多
关键词 Variable coefficient ordinary differential equations Lagrange interpolation Difference methods
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Geriatric assessment for predicting outcomes among patients with aortic stenosis undergoing transcatheter aortic valve implantation 被引量:1
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作者 Calvo E Castillo P +10 位作者 Romaguera R Llaó I Zafrilla R Domene G Alegre O Lorente V Muntané-Carol G Formiga F de la Cuerda FJ Gomez Hospital JA Ariza-Solè A 《Journal of Geriatric Cardiology》 2025年第5期516-524,共9页
Background There is scarce data about comparisons between geriatric assessment tools in patients with aortic stenosis(AS).We aimed to describe the geriatric profile of patients with AS undergoing transcatheter aortic ... Background There is scarce data about comparisons between geriatric assessment tools in patients with aortic stenosis(AS).We aimed to describe the geriatric profile of patients with AS undergoing transcatheter aortic valve implantation(TAVI)and to analyze the ability of different tools for predicting clinical outcomes in this context.Methods This was a single center retrospective registry including patients with AS undergoing TAVI and surviving to hospital discharge.The primary endpoint was all-cause mortality or need for urgent readmission one year after TAVI.Results A total of 377 patients were included(mean age of 80.4 years).Most patients were independent or mildly dependent,with an optimal cognitive status.The proportion of frailty ranged from 17.6%to 49.8%.A total of 20 patients(5.3%)died and 110/377 patients(29.2%)died or were readmitted during follow up.Overall,most components of the geriatric assessment showed an association with clinical outcomes.Disability for instrumental activities showed a significant association with mortality and a strong association with the rate of mortality or readmission.The association between frailty and clinical outcomes was higher for short physical performance battery(SPPB),essential frailty toolset(EFT)and the frailty index based on comprehensive geriatric assessment(IF-VIG)and lower for Fried criteria and FRAIL scale.Conclusions AS patients from this series presented a good physical performance,optimal cognitive status and a reasonably low prevalence of frailty.The best predictive ability was observed for disability for instrumental activities and frailty as measured by the EFT,SPPB and the IF-VIG. 展开更多
关键词 transcatheter aortic valve implantation tavi analyze ability different tools Geriatric Assessment describe geriatric profile geriatric assessment tools Transcatheter Aortic Valve Implantation FRAILTY Aortic Stenosis
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Spatial Patterns and Controlling Factors of Soil Organic Carbon and Total Nitrogen in the Three River Headwaters Region,China 被引量:1
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作者 CUI Qiao LI Zongxing +2 位作者 FENG Qi ZHANG Baijuan ZHAO Yue 《Chinese Geographical Science》 2025年第1期131-148,共18页
The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate ... The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate change on the structure,function,and services of the ecosystem.However,the spatial distribution and controlling factors of SOC and TN across various soil layers and vegetation types within this unique ecosystem remain inadequately understood.In this study,256 soil samples in 89 sites were collected from the Three River Headwaters Region(TRHR)in China to investigate SOC and TN and to explore the primary factors affecting their distribution,including soil,vegetation,climate,and geography factors.The results show that SOC and TN contents in 0-20,20-40,40-60,and 60-80 cm soil layers are 24.40,18.03,14.04,12.40 g/kg and 2.46,1.90,1.51,1.17 g/kg,respectively;with higher concentrations observed in the southeastern region compared to the northwest of the TRHR.One-way analysis of variance reveals that SOC and TN levels are elevated in the alpine meadow and the alpine shrub relative to the alpine steppe in the 0-60 cm soil layers.The structural equation model explores that soil water content is the main controlling factor affecting the variation of SOC and TN.Moreover,the geography,climate,and vegetation factors notably indirectly affect SOC and TN through soil factors.Therefore,it can effectively improve soil water and nutrient conditions through vegetation restoration,soil improvement,and grazing management,and the change of SOC and TN can be fully understood by establishing monitoring networks to better protect soil carbon and nitrogen. 展开更多
关键词 controlling factors different soil layers soil organic carbon(SOC) soil total nitrogen(TN) alpine ecosystem the Three River Headwaters Region(TRHR) China
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Acute Inflammatory Pain Induces Sex-different Brain Alpha Activity in Anesthetized Rats Through Optically Pumped Magnetometer Magnetoencephalography
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作者 MIAO Meng-Meng REN Yu-Xuan +5 位作者 WU Wen-Wei ZHANG Yu PAN Chen LIN Xiang-Hong LIN Hui-Dan CHEN Xiao-Wei 《生物化学与生物物理进展》 北大核心 2025年第1期244-257,共14页
Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interfe... Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interference devices(SQUID),MEG based on optically pump magnetometer(OPM)has the advantages of higher sensitivity,better spatial resolution and lower cost.However,most of the current studies are clinical studies,and there is a lack of animal studies on MEG based on OPM technology.Pain,a multifaceted sensory and emotional phenomenon,induces intricate alterations in brain activity,exhibiting notable sex differences.Despite clinical revelations of pain-related neuronal activity through MEG,specific properties remain elusive,and comprehensive laboratory studies on pain-associated brain activity alterations are lacking.The aim of this study was to investigate the effects of inflammatory pain(induced by Complete Freund’s Adjuvant(CFA))on brain activity in a rat model using the MEG technique,to analysis changes in brain activity during pain perception,and to explore sex differences in pain-related MEG signaling.Methods This study utilized adult male and female Sprague-Dawley rats.Inflammatory pain was induced via intraplantar injection of CFA(100μl,50%in saline)in the left hind paw,with control groups receiving saline.Pain behavior was assessed using von Frey filaments at baseline and 1 h post-injection.For MEG recording,anesthetized rats had an OPM positioned on their head within a magnetic shield,undergoing two 15-minute sessions:a 5-minute baseline followed by a 10-minute mechanical stimulation phase.Data analysis included artifact removal and time-frequency analysis of spontaneous brain activity using accumulated spectrograms,generating spectrograms focused on the 4-30 Hz frequency range.Results MEG recordings in anesthetized rats during resting states and hind paw mechanical stimulation were compared,before and after saline/CFA injections.Mechanical stimulation elevated alpha activity in both male and female rats pre-and post-saline/CFA injections.Saline/CFA injections augmented average power in both sexes compared to pre-injection states.Remarkably,female rats exhibited higher average spectral power 1 h after CFA injection than after saline injection during resting states.Furthermore,despite comparable pain thresholds measured by classical pain behavioral tests post-CFA treatment,female rats displayed higher average power than males in the resting state after CFA injection.Conclusion These results imply an enhanced perception of inflammatory pain in female rats compared to their male counterparts.Our study exhibits sex differences in alpha activities following CFA injection,highlighting heightened brain alpha activity in female rats during acute inflammatory pain in the resting state.Our study provides a method for OPM-based MEG recordings to be used to study brain activity in anaesthetized animals.In addition,the findings of this study contribute to a deeper understanding of pain-related neural activity and pain sex differences. 展开更多
关键词 MAGNETOENCEPHALOGRAPHY PAIN sex differences alpha activity INFLAMMATION
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Analysis of the effect of vibration on the homogeneity of the kinematic mechanism of an angular mirror translational interferometer
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作者 XU Xue-Rong PENG Yi-Tian +1 位作者 GU Ming-Jian JIANG Teng-teng 《红外与毫米波学报》 北大核心 2025年第3期425-430,共6页
The effect of external vibration on the velocity uniformity of the moving mechanism of the angular mir⁃ror translational Fourier transform interferometer(hereinafter referred to as interferometer)can be quantitatively... The effect of external vibration on the velocity uniformity of the moving mechanism of the angular mir⁃ror translational Fourier transform interferometer(hereinafter referred to as interferometer)can be quantitatively analysed by the interferometer optical range difference velocity stability.The article proposes a more comprehen⁃sive method of analysing the optical range difference velocity uniformity for the reliability of the interferometer ki⁃nematic mechanism under the influence of on-orbit microvibration in the process of space spectroscopy detection.The method incorporates the structural response of the interferometer caused by external excitation into the stabili⁃ty analysis as one of the influencing factors,so as to reflect the reliability of the interferometer in orbit more realis⁃tically,and judge the microvibration criticality that the interferometer can withstand more accurately.At the same time,an optical surface model of the interferometer is established to further theoretically characterise the effect of microvibration on the homogeneity of the interferometric mechanism.The method discussed in the article pro⁃vides a way of thinking for the judgement of the reliability of the mechanism movement under the external excita⁃tion perturbation as well as the research on the optimisation of the mechanism control. 展开更多
关键词 Fourier-interferometer optical range difference velocity stability TREMOR space spectroscopy detection
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Path Individuation and Retrospective Grounding
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作者 ZHENG Yujian 《自然辩证法通讯》 北大核心 2025年第12期37-51,共15页
This paper purports to expound a special(technical)notion of paths.A neglected fundamental fact(especially under indeterminism)is that the path-dependent direction of any diachronic outcome is backward,i.e.,later step... This paper purports to expound a special(technical)notion of paths.A neglected fundamental fact(especially under indeterminism)is that the path-dependent direction of any diachronic outcome is backward,i.e.,later steps depend on earlier ones successively,despite the ineradicable chance in their respective formation.In this paper,a token-oriented retrospective approach is proposed to overcome the limitation of the type-oriented approach in explaining path-related phenomena.My argument for the validity and utility of this approach is largely based on the elements of(PD),a definitional schema for diachronic sequences subject to a recursive counterfactual formula.I explore certain aspects of path individuation that have so far not been discussed,despite(PD)’s formal congeniality with Lewis’s‘causal chain’.Two basic patterns of path generation are examined:the first is for distinguishing actual vs possible branching paths,while the second introduces a metaphysical theme regarding the retrospective grounding of the causal status of an upstream event by its downstream(joint)effect.A central example of the paper,viz.,the Gobang game,is used to illustrate how the token-oriented approach works for path individuation. 展开更多
关键词 Path individuation Retrospective grounding Token-oriented approach Path dependence Diachronic difference making
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问答
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《物理》 北大核心 2025年第8期594-594,共1页
Q:为什么无法从粒子物理出发推导出凝聚态物理?A:听过一个讲座,临结束时报告人问了一个问题:大家都知道“More is different”,那有人知道这篇文章还有一个副标题是什么吗?全场鸦雀无声。查阅后得知副标题是“Broken symmetry and the n... Q:为什么无法从粒子物理出发推导出凝聚态物理?A:听过一个讲座,临结束时报告人问了一个问题:大家都知道“More is different”,那有人知道这篇文章还有一个副标题是什么吗?全场鸦雀无声。查阅后得知副标题是“Broken symmetry and the nature of the hierarchical structure of science”,翻译过来就是“破缺的对称性与科学层级结构的本质”。 展开更多
关键词 凝聚态物理 粒子物理 问答 More is different
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