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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:2
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Cross-phenotype genome-wide association study supports shared genetic etiology between skin and gastrointestinal tract diseases 被引量:1
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作者 Bo Peng Minghui Jiang +3 位作者 Si Li Xingyu Chen Shanshan Cheng Xingjie Hao 《Journal of Biomedical Research》 2026年第2期172-184,共13页
The comorbidity of skin and gastrointestinal tract(GIT)diseases,primarily driven by the gut-skin axis(GSA),is well established.However,the genetic contribution to the GSA remains unclear.Here,using genome-wide associa... The comorbidity of skin and gastrointestinal tract(GIT)diseases,primarily driven by the gut-skin axis(GSA),is well established.However,the genetic contribution to the GSA remains unclear.Here,using genome-wide association study(GWAS)summary statistics from European populations,we performed a genome-wide pleiotropic analysis to investigate the shared genetic basis and causal associations between skin and GIT diseases.We observed extensive genetic correlations and overlaps between skin and GIT diseases.A total of 298 pleiotropic loci were identified,75 of which were colocalized,and 61 exhibited pleiotropic effects across multiple trait pairs,including 2p16.1(PUS10),6p21.32(HLA-DRB1),10q21.2(ZNF365),and 19q13.11(SLC7A10).Additionally,five novel loci were identified based on the pleiotropic analysis;among them,the 15q22.2 locus harboring RORA was validated by the latest inflammatory bowel disease GWAS.Gene-based analysis identified 394 unique pleiotropic genes,which were enriched in GSA-associated tissues and the immune system,and protein-protein interaction analysis further revealed that the GPCR-cAMP,chromatin remodeling,JAK-STAT,and HLA-mediated immunity pathways were involved in GSA comorbidity.Notably,the JAK-STAT pathway showed strong potential for drug repurposing,with adalimumab targeting tumor necrosis factor and ustekinumab targeting interleukin-12 subunit beta already being used to treat both skin and GIT diseases.Finally,Mendelian randomization analysis identified five significant causal associations,and subsequent mediation analysis identified three potential microbiota-GIT-skin pathways.Taken together,our study demonstrated that the shared genetic factors between skin and GIT diseases were widely distributed across the genome.These findings will enhance our understanding of the genetic mechanisms underlying GSA comorbidity. 展开更多
关键词 gut-skin axis gastrointestinal tract diseases skin diseases pleiotropic analysis Mendelian randomization
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Targeting the brain’s glymphatic pathway:A novel therapeutic approach for cerebral small vessel disease 被引量:2
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作者 Yuhui Ma Yan Han 《Neural Regeneration Research》 2026年第2期433-442,共10页
Cerebral small vessel disease encompasses a group of neurological disorders characterized by injury to small blood vessels,often leading to stroke and dementia.Due to its diverse etiologies and complex pathological me... Cerebral small vessel disease encompasses a group of neurological disorders characterized by injury to small blood vessels,often leading to stroke and dementia.Due to its diverse etiologies and complex pathological mechanisms,preventing and treating cerebral small vessel vasculopathy is challenging.Recent studies have shown that the glymphatic system plays a crucial role in interstitial solute clearance and the maintenance of brain homeostasis.Increasing evidence also suggests that dysfunction in glymphatic clearance is a key factor in the progression of cerebral small vessel disease.This review begins with a comprehensive introduction to the structure,function,and driving factors of the glymphatic system,highlighting its essential role in brain waste clearance.Afterwards,cerebral small vessel disease was reviewed from the perspective of the glymphatic system,after which the mechanisms underlying their correlation were summarized.Glymphatic dysfunction may lead to the accumulation of metabolic waste in the brain,thereby exacerbating the pathological processes associated with cerebral small vessel disease.The review also discussed the direct evidence of glymphatic dysfunction in patients and animal models exhibiting two subtypes of cerebral small vessel disease:arteriolosclerosis-related cerebral small vessel disease and amyloid-related cerebral small vessel disease.Diffusion tensor image analysis along the perivascular space is an important non-invasive tool for assessing the clearance function of the glymphatic system.However,the effectiveness of its parameters needs to be enhanced.Among various nervous system diseases,including cerebral small vessel disease,glymphatic failure may be a common final pathway toward dementia.Overall,this review summarizes prevention and treatment strategies that target glymphatic drainage and will offer valuable insight for developing novel treatments for cerebral small vessel disease. 展开更多
关键词 AQUAPORIN-4 ASTROCYTES cerebral amyloid angiopathy cerebral small vessel disease cerebrospinal fluid diffusion tensor image analysis along the perivascular space glymphatic system interstitial fluid perivascular space therapeutic strategies
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Response of soil moisture to vegetation restoration:A bibliometric synthesis
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作者 GAN Shao'an HAN Lei +3 位作者 LI Yabei CHANG Yuqing ZHANG Hanxiao TUO Fengwei 《中国水土保持科学》 北大核心 2026年第1期270-284,共15页
[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucid... [Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucidating the global response patterns of soil moisture to vegetation restoration and identifying research hotspots are critical for guiding ecological construction in arid regions.[Methods]We reviewed 6,152 articles concerning soil moisture and vegetation retrieved from the Web of Science platform.Using VOSviewer,we conducted analyses of keyword co-occurrence,publication trends,and research hotspots to systematically delineate the evolving trends in this field.[Results]The results indicate a significant increasing trend in the number of publications since 2000.Global research keywords are categorized into seven clusters,including vegetation,soil moisture,rainfall-erosion-infiltration,spatial heterogeneity,and climate change.In terms of highly cited papers in 2024,China and the United States maintain a significant lead.Global research demonstrates a strong dependency on typical regional geographical features(such as climate types and topography),exhibiting differentiated research focuses.Furthermore,studies extend beyond soil moisture itself to deeply couple with ecological processes such as vegetation restoration,soil respiration,carbon cycling,and hydrothermal conditions.[Conclusions]The long-term ecological effects of afforestation in arid regions remain unclear,and empirical data from key regions highlight the current urgency.Future research should integrate climate change dynamics,innovate monitoring methodologies,and deepen the understanding of regional differentiation to provide scientific support for the adaptive management of vegetation in arid regions. 展开更多
关键词 soil moisture VEGETATION bibliometric analysis VOSviewer
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Visual Detection of Shrimp Freshness via Colorimetric Sensors
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作者 SONG Guangjie WANG Lei TIAN Yanqing 《高等学校化学学报》 北大核心 2026年第1期198-204,共7页
Monitoring biogenic amines,which are metabolic byproducts of shrimp spoilage,is crucial for assessing food quality.Currently,most detection methods for biogenic amines suffer from limitations such as time-consuming pr... Monitoring biogenic amines,which are metabolic byproducts of shrimp spoilage,is crucial for assessing food quality.Currently,most detection methods for biogenic amines suffer from limitations such as time-consuming procedures,complex operations,and delayed results.Colorimetric analysis techniques have gained attention in recent years due to their advantages of short analysis time,simple operation,and suitability for on-site testing.This study successfully developed a series of colorimetric sensor platforms for biogenic amines by loading the natural active ingredient curcumin(CUR)and its derivative of Boron complex BFCUR onto filter paper and electrospun nanofibre films(ENFs),respectively.By analyzing the color response differences of these sensors upon contact with biogenic amines,the colorimetric sensors with superior detection performance were selected and further applied to the visual monitoring and indication of shrimp spoilage processes. 展开更多
关键词 Shrimp freshness Colorimetric analysis Biogenic amine SENSOR
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Co(Ⅱ) and Ni(Ⅱ) complexes of 3,3-diphenylpropionic acid and 2,2′-dipyridylamine: Structures and biological activities
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作者 FENG Jing WANG Renshu +1 位作者 WANG Hu LIU Hailong 《无机化学学报》 北大核心 2026年第3期617-631,共15页
Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(... Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(PAm)]·2H_(2)O(2)were determined by single-crystal X-ray diffraction,IR spectroscopy,and powder X-ray diffraction.Hirshfeld surface analysis provided quantitative insights into the intermolecular interactions within the complexes,while molecular docking studies elucidated their binding modes and affinities toward urease.Furthermore,the biological activities of both complexes were systematically evaluated through a range of assays,including DNA binding,urease inhibition,antibacterial activity,and in vitro cytotoxicity against cancer cells.Both complexes exhibited binding affinity for DNA and displayed notable urease inhibitory activity.Under in vitro conditions,both complexes showed appreciable cytotoxicity toward HepG2 cells with efficacy comparable to clinically used platinumbased anticancer agents.CCDC:2479943,1;2479944,2. 展开更多
关键词 crystal structure computational analysis urease inhibition antibacterial activity CYTOTOXICITY
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Development of visible/near-infrared multiband laser filter film
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作者 XIN Ya-wu PENG Yong-chao +5 位作者 ZHANG Yu-xiang CAO Xing-yu HAN Yang GUO Hong-ling XIONG Shi-fu HU Zhang-gui 《中国光学(中英文)》 北大核心 2026年第1期239-249,共11页
Filters,as a key component in the photoelectric detection system,can simplify the optical system and improve detection efficiency.Based on the usage requirements,a visible/near-infrared filter film with up to 5 waveba... Filters,as a key component in the photoelectric detection system,can simplify the optical system and improve detection efficiency.Based on the usage requirements,a visible/near-infrared filter film with up to 5 wavebands needs to be designed and prepared,while simultaneously satisfying high reflection in 2 wave-bands and high transmittance in 3 wavebands.Therefore,we have conducted a systematic study on the film design,thin film preparation process,and control accuracy of film layer thickness.In this work,the short-wave pass film system is superimposed with the long-wave pass film system,and the number of cycles and matching coefficient of the film system are tuned to meet the requirements of cut-off band.Additionally,Smith method was used to match bandpass film system to optimize the transmission band and complete the visible/near infrared multiband laser filter film design.In the preparation process,combined with the sensitiv-ity of the film layer,inverse analysis is used to invert the film layer monitored by each optical monitoring chip.The optical control scheme with weak optical signal in the monitoring process is simulated and correc-ted,and the monitoring wavelength with stronger optical signal is matched,resulting in an improvement of the control accuracy for the film thickness and the transmittance in the specified wavelength range.Ulti-mately,the actual physical thickness is 9.66μm,and the error with the theoretical design thickness is less than 0.4%,and the transmittance of the specified 3 wavebands exceeds 99%.The average transmittance of the cut-off bands at the 455−500 nm and 910−1000 nm is 0.45% and 0.16%,respectively. 展开更多
关键词 optical film MULTIBAND film system design reverse analysis
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Review and Outlook on Utilization of Desert Sand in Cement-based Materials
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作者 NIU Jinghang WANG Yuan +3 位作者 ZHAO Hongyan JIANG Linbo LI Gang WANG Zhi 《材料导报》 北大核心 2026年第7期145-161,共17页
Many architectural research studies have focused on creating new materials to reduce the exploitation of non-renewable natural resources,achieve sustainable development,and reduce carbon emissions.Desert sand(DS)has a... Many architectural research studies have focused on creating new materials to reduce the exploitation of non-renewable natural resources,achieve sustainable development,and reduce carbon emissions.Desert sand(DS)has attracted interest from researchers who have conducted numerous experimental investigations as a possible replacement for river sand.The idea of utilising DS in place of natural fine aggregates in construction has been demonstrated in the literature.However,to analyse and gain confidence in using DS in concrete,a thorough study of its various properties is needed.Therefore,this study addresses the morphological,chemical,and physical characteristics of DS from multiple perspectives.This review presents a study on the durability of desert sand concrete(DSC)and the use of DS cement-based products,and highlights investigations on the design of mix proportions and fresh and hardened properties of DSC.Research issues are emerging around the use of DS in engineered cementitious composites(ECC)materials and the investigation of desert sand powder(DSP)as mineral admixtures.Many issues need to be resolved quickly,which is crucial for the use of DS.In summary,research on DS is still in its early stages,and no systematic research results have been obtained at present.This review makes several recommendations and attempts to explain why DS will likely be widely used as a building material in the future. 展开更多
关键词 desert sand fine aggregate substitute mineral admixtures MULTI-SCALE mechanism analysis
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Health Phys.Abstracts,Volume 129,Number 5
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《辐射防护》 北大核心 2026年第1期91-96,共6页
Discrete Bayesian Dose-response Analysis under Dose Uncertainty.Eduard Hofer1(1.3 Constance Road,Claremont,Cape Town 7708,South Africa.)Abstract:Establishing a relationship between disease and dose requires each indiv... Discrete Bayesian Dose-response Analysis under Dose Uncertainty.Eduard Hofer1(1.3 Constance Road,Claremont,Cape Town 7708,South Africa.)Abstract:Establishing a relationship between disease and dose requires each individual in the population under investigation to be known by disease status and by the value of the dose received. 展开更多
关键词 Bayesian analysis dose response relationship disease dose dose uncertainty
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Effect of Gradient Layer Thickness on Anti-penetration Properties of 2024 Al/TC4 Laminated Composites
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作者 Wang Kangan Li Muxi +1 位作者 Hou Hua Zhao Yuhong 《稀有金属材料与工程》 北大核心 2026年第5期1170-1183,共14页
A gradient structure was introduced into a metal laminated target plate,and the anti-penetration simulation of the gradient structure was compared with that of a uniform-layer-thickness target plate by finite element ... A gradient structure was introduced into a metal laminated target plate,and the anti-penetration simulation of the gradient structure was compared with that of a uniform-layer-thickness target plate by finite element simulation.The analysis was verified by an impact experiment.Results show that the high-level thickness and appropriate percentage of Ti alloy at the upper side of the gradient structure provide greater impact resistance against the bullet,which increases the warhead breakage and enhances the anti-penetration performance.In addition,during the impact process,the stress is transmitted and reflected in the form of waves in each layer of the target plate,and the interaction between the compression and tension waves causes non-synergistic deformation of the target plate and leads to delamination.The gradient target plate takes penetration resistance a step further through the higher energy absorption rate and more consumption of the bullet kinetic energy.This research provides a theoretical basis for the application of gradient structures in metallic laminated armor. 展开更多
关键词 gradient structure laminated composites finite element analysis anti-penetration mechanism
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Causal relationships of inflammatory cytokines and serum metabolites with colorectal carcinoma: A Mendelian randomization study
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作者 FENG Sisi XIAO Xiaomin +2 位作者 ZHOU Manli HUANG Zixin ZHONG Baiyun 《中南大学学报(医学版)》 北大核心 2026年第1期118-128,共11页
Objective:The incidence and mortality of colorectal carcinoma(CRC)continue to rise globally,highlighting the need to identify modifiable risk factors for early detection and prevention.Previous studies have demonstrat... Objective:The incidence and mortality of colorectal carcinoma(CRC)continue to rise globally,highlighting the need to identify modifiable risk factors for early detection and prevention.Previous studies have demonstrated significant associations between CRC risk and various serum metabolites as well as inflammatory cytokines;however,due to limitations in study design and potential confounding factors,the causal relationships remain unclear.This study aims to investigate the causal relationships between inflammatory cytokines,serum metabolites,and CRC risk,providing a theoretical basis for the development of novel early diagnostic biomarkers and therapeutic targets.Methods:A two-sample Mendelian randomization(MR)design was applied using summary statistics from genome-wide association studies(GWAS).Instrumental variables(IVs)were derived from:1)metabolomics GWAS data of 1400 serum metabolites(n=8299);2)cytokine GWAS data of 91 inflammatory factors(n=14824);and 3)CRC risk data from the FinnGen consortium(6847 cases and 314193 controls).The primary analysis was conducted using the inverse-variance weighted(IVW)method,with sensitivity analyses performed using MR Egger regression and the weighted median method.Effect estimates including odds ratios(OR),95%confidence intervals(CI),and false discovery rates(FDR)were calculated.Results:MR analysis indicated that higher levels of axin-1(AXIN1)(OR=0.84195%CI 0.714 to 0.991)and Fms-related tyrosine kinase 3 ligand(Flt3L)(OR=0.916,95%CI 0.844 to 0.994)were associated with a reduced risk of CRC.In contrast,higher levels of Delta/Notchlike epidermal growth factor-related receptor(DNER)(OR=1.119,95%CI 1.009 to 1.241)and vascular endothelial growth factor A(VEGF-A)(OR=1.078,95%CI 1.011 to 1.150)were associated with an increased risk of CRC(all P<0.05).Metabolomics association analysis further identified 144 serum metabolites significantly correlated with these four key inflammatory cytokines(FDR<0.05),suggesting that they may regulate CRC risk through inflammatory pathways.Conclusion:Specific inflammatory cytokines and serum metabolites have causal relationships with the risk of CRC.These findings provide insights for further exploration of potential risk factors and the development of effective prevention strategies for CRC. 展开更多
关键词 inflammatory cytokines serum metabolites colorectal carcinoma Mendelian randomization genome-wide association study metabolomics analysis
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Health Phys.Abstracts,Volume 129,Number 4
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《辐射防护》 北大核心 2026年第1期87-91,共5页
Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,... Analysis Method of ^(131)I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.Shuo Wang1,Fei Tuo1,Jian-feng Zhang1,Xiao-liang Li1,Bao-lu Yang1,Qiang Zhou1,Ze-shu Li1,Shu-ying Kong1,and Wei-hao Qin1(1.National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing,100088,China.) 展开更多
关键词 nuclear medicine workers health physics carbon cartridge internal dose assessment analysis method I activity
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Cavity ring-down spectroscopy CO gas sensor integrating principal component analysis with savitzky-golay filtering
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作者 GUO Zi-long SHI Cheng-rui +4 位作者 DONG Yuan-yuan ZHANG Lei SUN Xiao-yuan SUN Jing-jing ZHOU Sheng 《中国光学(中英文)》 北大核心 2026年第1期179-189,共11页
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni... The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility. 展开更多
关键词 cavity ring-down spectroscopy CO gas sensor principal component analysis Savitzky-Golay filter
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Intelligent Parameter Decision-Making and Multi-objective Prediction for Multi-layer and Multi-pass LDED Process
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作者 Li Yaguan Nie Zhenguo +2 位作者 Li Huilin Wang Tao Huang Qingxue 《稀有金属材料与工程》 北大核心 2026年第1期47-58,共12页
The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical m... The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical model height.The Taguchi method was employed to establish the correlations between process parameter combinations and multi-objective characterization of metal deposition morphology(height error and roughness).Results show that using the signal-to-noise ratio and grey relational analysis,the optimal parameter combination for multi-layer and multi-pass deposition is determined as follows:laser power of 800 W,powder feeding rate of 0.3 r/min,step distance of 1.6 mm,and scanning speed of 20 mm/s.Subsequently,a Genetic Bayesian-back propagation(GB-BP)network is constructed to predict multi-objective responses.Compared with the traditional back propagation network,the GB-back propagation network improves the prediction accuracy of height error and surface roughness by 43.14%and 71.43%,respectively.This network can accurately predict the multi-objective characterization of morphological quality of multi-layer and multi-pass metal deposited parts. 展开更多
关键词 multi-layer and multi-pass laser cladding Taguchi method grey relational analysis GB-BP network
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Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy
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作者 Sumbal Farid Jun-Hu Wang 《电化学(中英文)》 北大核心 2026年第1期42-64,共23页
Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements hav... Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm. 展开更多
关键词 Iron-based electrocatalyst In-situ/operando analysis Mössbauer spectroscopy Oxygen reduction reaction Structure-activity relationship
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Screening and determination of 23 local anesthetics in cosmetics using UPLC-Q-TOF-MS and HPLC-QQQ-MS/MS
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作者 Ruotong Yang Fangyuan Wu +3 位作者 Guangqian Xu Guiwen Guo Haiyan Wang Lingyun Jia 《日用化学工业(中英文)》 北大核心 2026年第2期260-270,共11页
The laboratory established an efficient reversed-phase ultra-high-performance liquid chromatographyquadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)qualitative method for screening more than 2000 kinds of ris... The laboratory established an efficient reversed-phase ultra-high-performance liquid chromatographyquadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)qualitative method for screening more than 2000 kinds of risk substances(including local anesthetics,LAs)in cosmetics,which has been successfully applied in the analysis of actual samples.This work aims to develop a more convenient high performance liquid chromatography triple quadrupole mass spectrometry(HPLC-QQQ-MS/MS)method for the quantitative determination of LAs.Samples were ultrasonically extracted with methanol,separated on an Agilent Poroshell 120 EC-C18 column(2.1 mm×100 mm,2.7μm),and eluted with a gradient mobile phase consisting of 0.1%formic acid aqueous solution and methanol.Quantification was performed using the external standard method.The results show that all 23 LAs are effectively separated within 12 minutes,with good linearity in the corresponding concentration ranges and the correlation coefficients all greater than 0.99.The limits of detection(LOD)range from 0.0025 to 0.05μg/g,and the limits of quantification(LOQ)range from 0.01 to 0.1μg/g.The average recoveries of the 23 LAs in 5 blank cosmetic matrices are 80.68%-117.57%,with the relative standard deviations(RSDs)less than 5.98%.This method has good precision and high accuracy,and is suitable for the determination of LAs in 5 cosmetic matrices. 展开更多
关键词 local anesthetics chemical analysis ultra-high-performance liquid chromatography-quadrupole time-offlight mass spectrometry(UPLC-Q-TOF-MS) high performance liquid chromatography triple quadrupole mass spectrometry(HPLC-QQQ-MS/MS)
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Machine learning identifies key cells and therapeutic targets during ferroptosis after spinal cord injury
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作者 Yigang Lv Zhen Li +10 位作者 Lusen Shi Huan Jian Fan Yang Jichuan Qiu Chao Li Peng Xiao Wendong Ruan Hao Li Xueying Li Shiqing Feng Hengxing Zhou 《Neural Regeneration Research》 2026年第6期2495-2505,共11页
Ferroptosis,a type of cell death that mainly involves iron metabolism imbalance and lipid peroxidation,is strongly correlated with the phagocytic response caused by bleeding after spinal cord injury.Thus,in this study... Ferroptosis,a type of cell death that mainly involves iron metabolism imbalance and lipid peroxidation,is strongly correlated with the phagocytic response caused by bleeding after spinal cord injury.Thus,in this study,bulk RNA sequencing data(GSE47681 and GSE5296)and single-cell RNA sequencing data(GSE162610)were acquired from gene expression databases.We then conducted differential analysis and immune infiltration analysis.Atf3 and Piezo1 were identified as key ferroptosis genes through random forest and least absolute shrinkage and selection operator algorithms.Further analysis of single-cell RNA sequencing data revealed a close relationship between ferroptosis and cell types such as macrophages/microglia and their intrinsic state transition processes.Differences in transcription factor regulation and intercellular communication networks were found in ferroptosis-related cells,confirming the high expression of Atf3 and Piezo1 in these cells.Molecular docking analysis confirmed that the proteins encoded by these genes can bind cycloheximide.In a mouse model of T8 spinal cord injury,low-dose cycloheximide treatment was found to improve neurological function,decrease levels of the pro-inflammatory cytokine inducible nitric oxide synthase,and increase levels of the anti-inflammatory cytokine arginase 1.Correspondingly,the expression of the ferroptosis-related gene Gpx4 increased in macrophages/microglia,while the expression of Acsl4 decreased.Our findings reveal the important role of ferroptosis in the treatment of spinal cord injury,identify the key cell types and genes involved in ferroptosis after spinal cord injury,and validate the efficacy of potential drug therapies,pointing to new directions in the treatment of spinal cord injury. 展开更多
关键词 bioinformatic analyses bulk-RNA sequencing cellular communication analysis ferroptosis machine learning analysis neurological function RNA velocity analysis single-cell RNA sequencing therapeutic drugs transcription factor analysis
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基于LCA-FEA评价优化模型的地震灾后救援包装-纸屋集成系统设计
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作者 杨才俊 汪雯 项思渝 《包装工程》 北大核心 2026年第2期125-130,186,共7页
目的实现地震灾后救援物资的快速运输,降低救援临时安置场所的搭建时间和成本。方法本研究通过对救援物资标准化装载、无人机运输,以及救援纸屋材料、结构、应用场域规划进行系统化梳理与创新,归纳出轻量抗压、快速部署、人文关怀、可... 目的实现地震灾后救援物资的快速运输,降低救援临时安置场所的搭建时间和成本。方法本研究通过对救援物资标准化装载、无人机运输,以及救援纸屋材料、结构、应用场域规划进行系统化梳理与创新,归纳出轻量抗压、快速部署、人文关怀、可持续性四项救援产品核心需求。经过生命周期评价(LCA)和有限元分析(FEA)量化救援纸屋包装设计的环境效益,验证其结构的可靠性,从而明确改进策略,进行设计的迭代优化。结果构建了基于LCA-FEA评价优化模型的设计方法并据此设计出一款可用于无人机投放,具备良好承重、防水、环保性能的救援“包装-纸屋”集成系统。结论本研究提高了地震灾后黄金救援时间物资运输的响应与部署效率,为高效救援链条提供关键技术支撑,保障了灾民生活与社群交流的基础需求,为灾后救援产品设计提供了新思路。 展开更多
关键词 地震灾后救援 救援纸屋 生命周期评价(Life Cycle Assessment LCA) 有限元分析(Finite Element Analysis FEA) 无人机运输
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