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Seasonal emission patterns of airborne phytoncides in temperate forests from autumn to early spring:a case study of Xishui National Forest Park(Yichun,Northeast China)
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作者 Hongda Cai Yitong Wang +6 位作者 Xianwen Huang Sen Zhang Yankun Liu Jian Zhang Dongmei Zhao Peng Zhao Xiuhua Zhao 《Journal of Forestry Research》 2026年第1期256-271,共16页
Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio ac... Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies. 展开更多
关键词 Phytoncides Seasonal variation Diurnal-nocturnal patterns Snowfall impact Emission patterns
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s... Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests. 展开更多
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Improving Online Restore Performance of Backup Storage via Historical File Access Pattern
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作者 Ruidong Chen Guopeng Wang +5 位作者 Jingyuan Yang Ziyu Wang Fang Zou Jia Sun Xingpeng Tang Ting Chen 《Computers, Materials & Continua》 2026年第3期1536-1558,共23页
The performance of data restore is one of the key indicators of user experience for backup storage systems.Compared to the traditional offline restore process,online restore reduces downtime during backup restoration,... The performance of data restore is one of the key indicators of user experience for backup storage systems.Compared to the traditional offline restore process,online restore reduces downtime during backup restoration,allowing users to operate on already restored files while other files are still being restored.This approach improves availability during restoration tasks but suffers from a critical limitation:inconsistencies between the access sequence and the restore sequence.In many cases,the file a user needs to access at a given moment may not yet be restored,resulting in significant delays and poor user experience.To this end,we present Histore,which builds on the user’s historical access sequence to schedule the restore sequence,in order to reduce users’access delayed time.Histore includes three restore approaches:(i)the frequency-based approach,which restores files based on historical file access frequencies and prioritizes ensuring the availability of frequently accessed files;(ii)the graph-based approach,which preferentially restores the frequently accessed files as well as their correlated files based on historical access patterns,and(iii)the trie-based approach,which restores particular files based on both users’real-time and historical access patterns to deduce and restore the files to be accessed in the near future.We implement a prototype of Histore and evaluate its performance from multiple perspectives.Trace-driven experiments on two datasets show that Histore significantly reduces users’delay time by 4-700×with only 1.0%-14.5%additional performance overhead. 展开更多
关键词 Online restore access pattern correlation graph TRIE
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Vascular plant diversity and distribution pattern in Tajikistan:A global hotspot of diversity
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作者 ZHOU Yixin MA Suliya +7 位作者 LI Wenjun Parvina KURBONOVA Mariyo BOBOEV LI Yufan Hikmat HISORIEV MA Keping YANG Weikang ZHANG Yuanming 《Regional Sustainability》 2026年第1期37-53,共17页
Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges... Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges.There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning.Therefore,this study integrated 4 key biodiversity indices including species richness(SR),phylogenetic diversity(PD),threatened species richness(TSR),and endemic species richness(ESR)to map species diversity distribution patterns,identify conservation gaps,and elucidate their effects of climatic factors.This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan.The central–western mountains(specifically the Gissar-Darvasian and Zeravshanian regions)emerge as irreplaceable biodiversity hotspots.However,we found a severe spatial mismatch between these priority areas and the existing protected areas(PAs).Protection coverage for all hotspots was alarmingly low,ranging from 31.00%to 38.00%.Consequently,a critical 64.80%of integrated priority areas fall outside of the current PAs,representing a major conservation gap.This study identified precipitation seasonality and isothermality as the principal drivers,collectively explaining over 50.00%of the diversity variation and suggesting high vulnerability to hydrological shifts.Furthermore,we detected significant geographic sampling bias in the public biodiversity databases,with the most critical hotspot being systematically under-sampled.This study provides a robust scientific basis for conservation action,highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys.These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3(“30×30 Protection”). 展开更多
关键词 Vascular plant Species diversity Distribution pattern Conservation gaps TAJIKISTAN
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Patterned line-illumination mesoscopy with a moving slit for enhancing background suppression in cortex-wide mouse brain imaging
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作者 Chaowei Zhuang Yi Yang Hao Xie 《Chinese Physics B》 2026年第2期679-684,共6页
Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the im... Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the image quality and hinders neuronal signal extraction.To address this problem,we first introduce a cortex-wide,high-resolution lineillumination mesoscope with a moving slit designed for in vivo mouse brain imaging.This system achieves a 6.6×6.6 mm FOV,microscale cellular resolution,a high frame rate of 10 Hz,as well as the background rejection ability.Furthermore,we integrated patterned illumination into the system to enhance the background suppression.Experimental results show that the proposed system successfully captures neurodynamics in the living mouse brain.Compared with conventional wide-field mesoscopes,the cortex-wide patterned line-illumination mesoscope(PLIM)achieves a threefold increase in the signal-to-background ratio(SBR).With patterned illumination integrated,the SBR enhancement further reaches four-anda-half-fold. 展开更多
关键词 wide-field fluorescence imaging optical sectioning patterned illumination
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Unravelling tree diversity patterns and responses to environmental gradients in a tropical forest landscape of the Western Ghats
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作者 Naveen Babu Kanda Ashaq Ahmad Dar +2 位作者 Kurian Ayushi Ayyappan Narayanan Narayanaswamy Parthasarathy 《Plant Diversity》 2026年第1期92-106,共15页
Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the She... Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers ofα-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation inα-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems. 展开更多
关键词 Alpha diversity Beta diversity Machine learning Structural equation modeling Vegetation patterns Western Ghats
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Mineral resources of Asia continent:Resource endowment,mining industry pattern,and contributions to the world economy
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作者 Xi-feng Chen Gang Wang +2 位作者 Yan-xiong Mei Hai-jie Zhao Yan-yun Ma 《China Geology》 2026年第1期1-24,共24页
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral... Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation. 展开更多
关键词 Mineral resource endowment Minerogenetic series Metallogenic specialization Carbonate-type REE deposits Weathering-type REE deposits Hard rock-type lithium deposits Laterite nickel deposits Crystalline graphite deposits Magmatic nickel deposits Significant metallogenic belt Mining industry development pattern Mineral exploration and exploitation World economy Contribution Asia continent
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基于ILBP特征与XGBoost的烟支外观缺陷检测
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作者 杨彪 王俊杰 李华文 《陕西理工大学学报(自然科学版)》 2025年第5期53-62,共10页
烟支外观缺陷是决定卷烟品质和企业品牌影响力的重要因素,而传统人工检测方法的效率难以满足高速卷烟机组检测需求,为提升烟支产品竞争力和自动化检测水平,提出了一种基于改进局部二值模式(ILBP)与极限梯度提升(XGBoost)模型的烟支外观... 烟支外观缺陷是决定卷烟品质和企业品牌影响力的重要因素,而传统人工检测方法的效率难以满足高速卷烟机组检测需求,为提升烟支产品竞争力和自动化检测水平,提出了一种基于改进局部二值模式(ILBP)与极限梯度提升(XGBoost)模型的烟支外观图像分类方法。首先,为保证图像质量和清晰度,对采集的缺陷烟支图像进行灰度化和平滑滤波处理;然后,将预处理后的缺陷烟支图像利用改进LBP描述符进行特征提取,以降低LBP特征维度之间冗余性和提升特征表达能力;最后,使用XGBoost对缺陷烟支进行分类识别,并引入改进粒子群优化算法对XGBoost超参数进行迭代优化,以提升模型分类性能。结果表明,该方法在自建缺陷烟支数据集上识别率达96.8%,单张图片检测时间4.9 ms,检测精度和时间均优于对比模型。该方法可为烟支外观缺陷检测提供一种新思路。 展开更多
关键词 烟支外观 缺陷检测 改进lbp 改进粒子群优化算法 极限梯度提升
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基于改进的LBP和Gabor滤波器的纹理特征提取方法 被引量:2
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作者 陈佳明 陈旭 +1 位作者 任硕 邸宏伟 《南京信息工程大学学报》 北大核心 2025年第2期227-234,共8页
纹理提取是计算机视觉领域的一项重要任务,纹理提取的质量对纹理分类的准确性具有关键影响.传统单一的纹理提取方法难以准确描述各类纹理的特征.本文提出一种基于改进的位置局部二值模式(IPLBP)和Gabor滤波器的纹理提取算法,其中,改进... 纹理提取是计算机视觉领域的一项重要任务,纹理提取的质量对纹理分类的准确性具有关键影响.传统单一的纹理提取方法难以准确描述各类纹理的特征.本文提出一种基于改进的位置局部二值模式(IPLBP)和Gabor滤波器的纹理提取算法,其中,改进算法在局部二值模式(LBP)的基础上通过提取纹理位置信息来提高纹理描述能力.利用改进后的LBP算法提取局部纹理信息,Gabor滤波器提取全局纹理信息,将两种特征信息进行融合后使用支持向量机(SVM)进行分类.实验结果表明,所提出的算法在纹理材质分类任务上展现出了良好的性能.相比传统的LBP算法,该算法能够更准确地捕捉不同纹理特征之间的差异. 展开更多
关键词 纹理提取 局部二值模式 GABOR滤波器 支持向量机
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基于改进LBP的煤田断层识别方法研究
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作者 皇范蕤 黄亚平 +2 位作者 祁雪梅 程彦 周玲玲 《地球物理学进展》 北大核心 2025年第6期2642-2655,共14页
断层构造作为影响煤矿安全生产的关键地质因素,其精确识别对煤矿勘探开发阶段的灾害防控和高效开采极为重要.因此,本文针对地震资料中的断层构造开展边缘检测技术方面的研究,在分析前人研究成果的基础上,提出了一种联合旋转不变局部二... 断层构造作为影响煤矿安全生产的关键地质因素,其精确识别对煤矿勘探开发阶段的灾害防控和高效开采极为重要.因此,本文针对地震资料中的断层构造开展边缘检测技术方面的研究,在分析前人研究成果的基础上,提出了一种联合旋转不变局部二值模式(Local Binary Pattern,LBP)与旋转不变方差(Rotation Invariant Variance,VAR)的LBP/VAR复合算子边缘检测方法.首先,建立了垂直断距连续变化的理论地质模型,使用不同的算子对正演模拟的结果进行检测,证明LBP/VAR算子的识别精度较好.然后引入不同信噪比的噪声,通过与旋转不变局部二值模式、Canny、Roberts等传统边缘检测算子对比,验证了LBP/VAR算子在噪声干扰下的稳定性.随后,将所提方法应用于实际煤田地震资料,并与常规地震属性、传统边缘检测算子和旋转不变局部二值模式的检测结果进行对比.实验结果表明,LBP/VAR算子通过纹理特征与对比度的协同分析,在断层识别精度和抗噪性方面均展现出显著优势.本研究成果可以为煤层断层的定性识别提供参考,并对煤层后期的勘探开发具有一定的指导意义. 展开更多
关键词 断层构造 lbp/VAR 边缘检测 正演模拟 纹理特征
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LBP3促进SCFAs生成以抑制PMN-MDSC功能发挥抗肿瘤作用
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作者 蔡燕萍 张美玲 +7 位作者 谢旭婷 梁俊杰 朱颖 邓向亮 陈允亮 罗霞 周联 王青 《中国免疫学杂志》 北大核心 2025年第7期1543-1551,共9页
目的:探讨LBP3是否通过促进肠道菌群产生短链脂肪酸(SCFAs)调节多形核骨髓来源抑制性细胞(PMN-MDSC)功能发挥抗肿瘤作用。方法:采用H22肝癌皮下移植瘤模型,评估LBP3抑瘤活性及对PMN-MDSC的调节作用;伪无菌荷瘤小鼠模型考察肠道菌群在LBP... 目的:探讨LBP3是否通过促进肠道菌群产生短链脂肪酸(SCFAs)调节多形核骨髓来源抑制性细胞(PMN-MDSC)功能发挥抗肿瘤作用。方法:采用H22肝癌皮下移植瘤模型,评估LBP3抑瘤活性及对PMN-MDSC的调节作用;伪无菌荷瘤小鼠模型考察肠道菌群在LBP3抑瘤中的作用;利用粪便微生物移植(FMT)研究LBP3的药效机制;液质联用技术检测荷瘤小鼠血清SCFAs水平,并体外考察SCFAs中丁酸对精氨酸酶1(Arg-1)的影响。结果:低剂量(125 mg/kg)和高剂量(250mg/kg)LBP3明显抑制H22荷瘤生长,且显著降低脾脏和肿瘤中PMN-MDSC和淋巴结中Treg占比及Arg-1水平,并增加肿瘤中CD8+T细胞浸润,而LBP3在伪无菌小鼠中未见此作用,但移植LBP3高剂量治疗组粪便上清后可重现上述变化,证明LBP3通过肠道菌群发挥药效。此外,还发现PMN-MDSC标志Ly6G和SCFA受体GPR43在肿瘤组织中有共同表达现象,且LBP3可提高血液和肿瘤中以丁酸为主的SCFAs水平。丁酸抑制MSC-2细胞Arg-1表达,进一步证明SCFAs是LBP3免疫调节的重要介质。结论:LBP3可通过增加肠道菌群产生SCFAs抑制PMN-MDSC功能发挥抗肿瘤作用,LBP3有望成为恶性肿瘤治疗的免疫调节剂。 展开更多
关键词 lbp3 多形核骨髓来源的抑制性细胞 肿瘤免疫 短链脂肪酸
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应用染色放大内镜进行JNET分型与Pit pattern分型在结直肠侧向发育型肿瘤中的诊断价值分析
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作者 黄波 赵丽然 +4 位作者 张晓旭 张玲 涂征艳 王春晖 高天霞 《中国实用医药》 2025年第7期19-23,共5页
目的应用染色放大内镜对结直肠侧向发育型肿瘤(LST)患者进行日本内镜窄带光成像(NBI)技术专家小组(JNET)分型、Pit pattern分型,探究其诊断价值和临床意义。方法108例疑似结直肠LST并接受内镜黏膜下剥离术(ESD)患者,通过术前应用染色放... 目的应用染色放大内镜对结直肠侧向发育型肿瘤(LST)患者进行日本内镜窄带光成像(NBI)技术专家小组(JNET)分型、Pit pattern分型,探究其诊断价值和临床意义。方法108例疑似结直肠LST并接受内镜黏膜下剥离术(ESD)患者,通过术前应用染色放大内镜进行JNET、Pit pattern分型,并与ESD术后病理结果进行一致性分析,对比JNET分型及Pit pattern分型对结直肠LST的诊断效能。结果108例患者最终术后病理分型为非肿瘤性病变25例,肿瘤性病变83例。Pitpattern分型诊断结果与病理诊断结果有一定的一致性,差异具有显著统计学意义(Kappa值=0.519,P<0.001)。JNET分型诊断结果与病理诊断结果有一定的一致性,差异具有显著统计学意义(Kappa值=0.452,P<0.001)。JNET分型及Pit pattern分型诊断结直肠LST的特异度、阳性预测值、阴性预测值对比无显著差异(P>0.05)。JNET分型诊断结直肠LST的敏感度98.8%、准确率88.9%明显高于Pit pattern分型的91.6%、78.7%,差异具有统计学意义(P<0.05)。结论应用染色放大内镜进行JNET分型与Pit pattern分型对结直肠LST诊断具有良好价值,JNET分型优于Pitpattern分型。 展开更多
关键词 染色放大内镜 侧向发育型肿瘤 日本内镜窄带光成像技术专家小组分型 Pit pattern分型 诊断价值
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MB-LBP特征在车载LiDAR点云城市路坎点提取中的应用
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作者 王亚敏 王竞雪 《遥感信息》 北大核心 2025年第2期104-114,共11页
针对城市道路中弯道、路口等点云分布稀疏区域对细微变化处路坎点提取敏感度低的问题,引入MB-LBP特征将其用于路坎点提取,在9×9窗口内通过结合MB-LBP与路坎的多维几何特征精确提取路坎点。该方法首先对点云数据进行预处理,得到路... 针对城市道路中弯道、路口等点云分布稀疏区域对细微变化处路坎点提取敏感度低的问题,引入MB-LBP特征将其用于路坎点提取,在9×9窗口内通过结合MB-LBP与路坎的多维几何特征精确提取路坎点。该方法首先对点云数据进行预处理,得到路坎点高度、离散度以及法向量的特征图像。其次,基于3种特征图像分别提取MB-LBP特征,并以此构建多特征MB-LBP识别图像以提取候选路坎点。最后,采用KANN-DBSCAN算法对候选路坎点进行聚类去噪,得到精确的路坎点。为验证该方法的有效性,使用Paris-Lille-3D和Toronto-3D 4组不同类型城市环境的开源数据集进行实验。实验结果表明,针对文章的4组实验数据,路坎点提取的平均精度达到80%以上。该方法在有效自动识别路坎点的前提下,通过充分利用路坎的几何特征和MB-LBP特征增强的覆盖范围,显著提升了弯道、路口等点云分布稀疏区域对细微纹理变化的敏感度,使其在这些区域展现良好的适应性。 展开更多
关键词 稀疏区域 MB-lbp 多特征图像 KANN-DBSCAN 聚类去噪
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改进LBP和CNN相结合的疲劳驾驶检测方法
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作者 黄燕卿 英红 《桂林电子科技大学学报》 2025年第1期69-75,共7页
针对因面部疲劳信息不全或局部丢失致使驾驶员疲劳状态不能够充分表征,导致疲劳检测准确率不高的问题,提出了一种基于面部区域增加权重的分块LBP特征纹理提取方法。基于不同光线条件下的驾驶员图像,构建了疲劳识别的基本图像数据集,通... 针对因面部疲劳信息不全或局部丢失致使驾驶员疲劳状态不能够充分表征,导致疲劳检测准确率不高的问题,提出了一种基于面部区域增加权重的分块LBP特征纹理提取方法。基于不同光线条件下的驾驶员图像,构建了疲劳识别的基本图像数据集,通过自建数据集、预处理和数据增强,完成数据集样本图像的采集和归纳。提出了一种8×8块加权LBP算法,并用其从数据集图像中提取驾驶员的面部特征纹理,将作为卷积神经网络的输入以进行模型学习与训练。实验结果表明,所提算法特征提取速度快,仅耗时0.01s,且疲劳检测模型具有良好的识别精度和泛化能力,模型准确率为93.52%。所提算法不仅能够保留图像纹理变化表征能力,还能有效降低特征冗余,为驾驶员疲劳状态的识别提供了一种可行的方法。 展开更多
关键词 事故预防 疲劳驾驶识别 面部特征权重 局部二值模式(lbp) 卷积神经网络(CNN)
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Recent advances of photolithography patterning of quantum dots for micro-display applications 被引量:1
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作者 Xuemin Kong Xiaotong Fan +6 位作者 Yuhui Wang Yunshu Luo Yihang Chen Tingzhu Wu Zhong Chen Yue Lin Shuli Wang 《Nano Materials Science》 2025年第1期49-64,共16页
The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and... The preparation of red,green,and blue quantum dot(QD)pixelated arrays with high precision,resolution,and brightness poses a significant challenge on the development of advanced micro-displays for virtual,augmented,and mixed reality applications.Alongside the controlled synthesis of high-performance QDs,a reliable QD patterning technology is crucial in overcoming this challenge.Among the various methods available,photolithography-based patterning technologies show great potentials in producing ultra-fine QD patterns at micron scale.This review article presents the recent advancements in the field of QD patterning using photolithography techniques and explores their applications in micro-display technology.Firstly,we discuss QD patterning through photolithography techniques employing photoresist(PR),which falls into two categories:PRassisted photolithography and photolithography of QDPR.Subsequently,direct photolithography techniques based on photo-induced crosslinking of photosensitive groups and photo-induced ligand cleavage mechanisms are thoroughly reviewed.Meanwhile,we assess the performance of QD arrays fabricated using these photolithography techniques and their integration into QD light emitting diode display devices as well as color conversionbased micro light emitting diode display devices.Lastly,we summarize the most recent developments in this field and outline future prospects. 展开更多
关键词 Quantum dot PHOTOLITHOGRAPHY patterning technology Micro-display
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Construction and optimization of ecological security pattern in karst basin considering lithology and geological disasters 被引量:2
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作者 LU Hongxing ZHAO Yuluan +1 位作者 CHEN Zhengshan LI Yuan 《Journal of Mountain Science》 2025年第3期983-1000,共18页
Ecological security provides the basis of maintaining both a sustainable regional ecosystem and economic development.However,few studies have focused on how the features such as topography and geomorphology,lithologic... Ecological security provides the basis of maintaining both a sustainable regional ecosystem and economic development.However,few studies have focused on how the features such as topography and geomorphology,lithologic stratigraphic assemblages,and geohazard distribution affect the construction of ecological security patterns and the layout of optimization measures.In order to comprehensively reveal the key areas and key objects of ecological restoration in karst basins,this study takes the Beipan River Basin(BRB)as an example,constructs an ecological security pattern(ESP)based on the methods of morphological spatial pattern analysis(MSPA),landscape connectivity analysis and circuit theory,and lays out the optimization measures in combination with the spatial distribution characteristics of topographic and geomorphological differences and lithological stratigraphic combinations.The results show that 151 ecological sources,343 ecological corridors,121 pinch points and 178 barriers constitute the ESP of the BRB.Lithology is closely related to the spatial distribution characteristics of ecological source sites.Level 1 and 2 ecological sources(The ecological sources were categorized into level 1,level 2,and level 3 source from high to low importance.)are concentrated in the Emeishan basalt region of the upstream and the clastic and impure carbonate rock region of the downstream part of the BRB;level 3ecological sources are concentrated in the carbonate rock region of the midstream.Taking into account the outstanding ecological problems in the basin,and based on the characteristics of lithology and geohazard distribution,we propose the optimization scheme of“three axes,three zones and multiple points”for the ESP and the layout of specific measures of the BRB.The results can provide scientific references for maintaining ecological security maintenance in karst ecologically fragile areas. 展开更多
关键词 Beipan River Basin Ecological security pattern LITHOLOGY GEOHAZARDS Circuit theory Karst mountainous area
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Characterizing Pattern of Topography and Geomorphology in the Hengduan Mountains, Southwest China 被引量:1
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作者 Youjun Chen Yanying Chen +1 位作者 Xiaokang Hu Jianmeng Feng 《Journal of Environmental & Earth Sciences》 2025年第1期414-422,共9页
The Hengduan Mountains,situated on the southeastern edge of the Qinghai-Tibet Plateau,are the longest and widest north-south-oriented mountain range in China,exerting a significant influence on the ecological and geog... The Hengduan Mountains,situated on the southeastern edge of the Qinghai-Tibet Plateau,are the longest and widest north-south-oriented mountain range in China,exerting a significant influence on the ecological and geographical pattern.Understanding the topographic and geomorphological characteristics of the Hengduan Mountains is fundamental and crucial for research in related fields such as ecology,geography,and sustainability.In this study,Digital Elevation Model(DEM)data were utilized to extract and analyze the topography and geomorphology(TG)pattern.TG maps have been developed to quantitatively classify the TG types in the Hengduan Mountains by combining the five factors of elevation,slope,aspect,relief and landform.The spatial distribution and quantitative characteristics of these factors were mapped and investigated using geographic information systems.The results revealed that:(1)The Hengduan Mountains exhibit an elongated north-south distribution,with an average elevation of approximately 3746 m,an average slope of around 25°,and an average relief of about 266 m.(2)The Hengduan Mountains display significant elevation differences,with an overall high elevation,characterized by a trend of lower elevation in the east and higher elevation in the west,as well as irregular orientations of various aspects.(3)The 19 landform types were identified,the landform types of the Hengduan Mountains are primarily composed of low-relief high-mountains(42.0618%),low-relief mid-mountains(22.4624%),and high-elevation hills(20.5839%).The results of the study can provide data and information support for the ecology,environmental protection and sustainable development of the Hengduan Mountains. 展开更多
关键词 TOPOGRAPHY GEOMORPHOLOGY Spatial pattern Digital Terrain Analysis Hengduan Mountains
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Endogenous endophthalmitis due to Klebsiella pneumoniae liver abscess:a retrospective study of clinical course,treatment pattern,and prognosis 被引量:1
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作者 Gyu Chul Chung Dong Sun Kim +4 位作者 Ji Eun Lee Iksoo Byon Sung Who Park Han Jo Kwon EunAh Kim 《International Journal of Ophthalmology(English edition)》 2025年第8期1553-1560,共8页
AIM:To report the demographic and systemic characteristics of patients,clinical progression of endophthalmitis,and the efficacy of various treatment strategies,with a focus on identifying key factors for preserving vi... AIM:To report the demographic and systemic characteristics of patients,clinical progression of endophthalmitis,and the efficacy of various treatment strategies,with a focus on identifying key factors for preserving vision in eyes with endogenous endophthalmitis due to Klebsiella pneumoniae(K.pneumoniae)liver abscess.METHODS:In this single-center,retrospective case series of 18 patients with endogenous endophthalmitis due to K.pneumoniae liver abscess were analyzed.Ophthalmologic features of endophthalmitis at early,intermediate and advanced stages were obtained from eyes with endophthalmitis of different severities.Prompt vitrectomy was considered primarily for all eyes except for very early endophthalmitis.Intravitreal injections of antibiotics were performed in eyes with endophthalmitis in the very early stages and in eyes where vitrectomy was not available,and additional control of infection was needed after vitrectomy.Evisceration was performed in eyes with corneoscleral perforation,advanced endophthalmitis,perforation with preseptal or orbital cellulitis,uncontrolled infection,or severe pain with no vision.RESULTS:Mean(±standard deviation)age of the 18 patients with endophthalmitis was 64.5±12.2(range:32-84)y,and 14 patients(77.8%)were males.Endophthalmitis tended to involve the retinal parenchyma first and then progressed into the vitreous cavity and anterior segments.However,it presented a tendency to cause massive subretinal abscesses even after vitrectomy with silicone oil tamponade.Very high intraocular pressure with new vessels on the iris(41.7%)were also commonly observed.Although all but three patients had systemic disease such as diabetes or hypertension,visual prognosis after treatment did not appear to depend significantly on underlying comorbidities.A final best-corrected visual acuity better than 20/60 was achieved only when lesions were detected very early,with relatively good initial visual acuity,likely reflecting lower bacterial inoculation in the eye.CONCLUSION:Detection of early endophthalmitis lesions appears to be the only way to preserve good vision in patients with K.pneumoniae liver abscesses.Therefore,proper guidelines for ophthalmologic screening remain to be established for subjects at a high risk of endophthalmitis. 展开更多
关键词 endogenous endophthalmitis Klebsiella pneumoniae liver abscess treatment pattern
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Regional differences and formation mechanisms of watershed territorial space patterns evolution:A case study of the critical areas in the Pearl River Basin 被引量:2
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作者 LIN Shugao WANG Pengcheng +2 位作者 ZHU Peixin HUANG Ke LU Rucheng 《Journal of Geographical Sciences》 2025年第5期941-963,共23页
Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guang... Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin. 展开更多
关键词 territorial space patterns urban-agricultural-ecological space(UAES) formation mechanisms regionaldifferences Pearl River Basin
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