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《The Unbearable Lightness of Being》的文体学解读
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作者 孙昕昕 《卫生职业教育》 2010年第19期156-157,共2页
1《The Unbearable Lightness of Being》简介 《The Unbearable Lightness of Being》是捷克作家米兰·昆德拉的作品,发表于1984年。其被我国读者所了解应在1987年韩少功和韩刚合译该书之后。自此,专家学者们对小说又有了一系... 1《The Unbearable Lightness of Being》简介 《The Unbearable Lightness of Being》是捷克作家米兰·昆德拉的作品,发表于1984年。其被我国读者所了解应在1987年韩少功和韩刚合译该书之后。自此,专家学者们对小说又有了一系列的重译和解读。本文讨论所使用的是Michael Henry Heim所翻译的英文电子版. 展开更多
关键词 文体学 轻与重 《The Unbearable lightness of Being》
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Lightness Perception Model for Natural Images
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作者 Xianglin Meng Zhengzhi Wang 《Journal of Software Engineering and Applications》 2010年第7期696-703,共8页
A perceptual lightness anchoring model based on visual cognition is proposed. It can recover absolute lightness of natural images using filling-in mechanism from single-scale boundaries. First, it adapts the response ... A perceptual lightness anchoring model based on visual cognition is proposed. It can recover absolute lightness of natural images using filling-in mechanism from single-scale boundaries. First, it adapts the response of retinal photoreceptors to varying levels of illumination. Then luminance-correlated contrast information can be obtained through multiplex encoding without additional luminance channel. Dynamic normalization is used to get smooth and continuous boundary contours. Different boundaries are used for ON and OFF channel diffusion layers. Theoretical analysis and simulation results indicate that the model could recover natural images under varying illumination, and solve the trapping, blurring and fogging problems to some extent. 展开更多
关键词 PERCEPTION lightness ANCHORING FILLING in ADAPTATION Multiplex CONTRAST
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Preprocessing of Separating Leukocytes Based on Setting Parameters of Lightness Transformation
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作者 Jianyong Cai Lili Luo +2 位作者 Rongtai Cai Lijin Lin Juan Cai 《Journal of Signal and Information Processing》 2013年第4期400-406,共7页
This paper proposed a new algorithm to separate leukocytes from cytological image by setting parameters of lightness transformation based on the RGB color space, which can make the targets’ color in different areas. ... This paper proposed a new algorithm to separate leukocytes from cytological image by setting parameters of lightness transformation based on the RGB color space, which can make the targets’ color in different areas. In our procedure, an operator is employed in using color features. According to their histogram distribution of hue component in HSL color space after enhancing the contrast of image in RGB color space, the threshold of segmentation between leukocyte and erythrocyte could be achieved well. Especially, this algorithm is more efficient than monochrome for leukocyte segmentation, and the results of experiments show that it provides a good tool for cytological image, which can increase accuracy of segmentation of leukocyte. 展开更多
关键词 Parameters lightness TRANSFORMATION Color Features HSL Threshold LEUKOCYTE Segmentation
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斯托克斯定理的形式化及其初步应用
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作者 刘永梅 王国辉 +3 位作者 关永 张景芝 施智平 董璐 《计算机工程与科学》 北大核心 2025年第6期1050-1061,共12页
斯托克斯定理是场论中的重要定理之一,它在流体力学、电磁学等领域都有广泛的应用。然而在实际应用中,斯托克斯定理前提条件的满足往往得不到正式的验证,这就存在一定的风险。因此,有必要对斯托克斯定理进行验证。基于斯托克斯定理的数... 斯托克斯定理是场论中的重要定理之一,它在流体力学、电磁学等领域都有广泛的应用。然而在实际应用中,斯托克斯定理前提条件的满足往往得不到正式的验证,这就存在一定的风险。因此,有必要对斯托克斯定理进行验证。基于斯托克斯定理的数学定义,构建其形式化模型,通过分析斯托克斯定理的数学证明过程,得出其形式化证明推导思路,根据分析、构建和验证目标,完成定理的形式化证明,最后将斯托克斯定理证明应用到管道流量设计模型的验证中。 展开更多
关键词 形式化验证 定理证明 斯托克斯定理 HOL Light
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基于RF-Light GBM的分组密码算法识别方案
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作者 董秀则 杨鸿刚 +1 位作者 胡一凡 于庚辰 《北京电子科技学院学报》 2025年第2期1-10,共10页
密码算法的识别在密码分析领域中具有重要意义。目前主流分组密码算法识别方案中密文特征提取普遍基于随机性检测标准。为解决短样本识别需求以及进一步提高识别准确率,本研究提出了一种基于RF-Light GBM的分组密码体制识别方案。首先通... 密码算法的识别在密码分析领域中具有重要意义。目前主流分组密码算法识别方案中密文特征提取普遍基于随机性检测标准。为解决短样本识别需求以及进一步提高识别准确率,本研究提出了一种基于RF-Light GBM的分组密码体制识别方案。首先通过GM/T 0005-2021随机性检测标准提取密文特征,其次利用随机森林算法对高维的数据进行重要性排序和筛选,然后利用特征向量训练Light GBM算法模型构建密码算法识别分类器进行识别。实现了短样本环境下高效识别未知密文的识别需求。在两两识别实验中,与现有研究相比本方案准确率整体提升约12%;多分类实验显示准确率均在73%以上,验证了本方案在分组密码算法识别中的有效性和优势,为未来在更复杂的加密模式下进行密码算法识别提供了参考。 展开更多
关键词 分组密码 机器学习 随机性检测 密码算法识别 Light GBM
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基于TCGA数据库资料评估头颈鳞状细胞癌患者Klotho基因表达与临床预后的关系
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作者 张学聪 陈秉辉 +2 位作者 徐常艳 常方远 曹华 《中国耳鼻咽喉头颈外科》 2025年第1期48-50,共3页
目的探讨基于癌症基因组图谱(TCGA)数据库资料评估头颈鳞状细胞癌(head neck squamous cell carcinoma,HNSCC)患者Klotho基因表达对临床预后的影响。方法研究通过检索TCGA数据库收集HNSCC患者Klotho基因、微管相关蛋白轻链3(Microtubule... 目的探讨基于癌症基因组图谱(TCGA)数据库资料评估头颈鳞状细胞癌(head neck squamous cell carcinoma,HNSCC)患者Klotho基因表达对临床预后的影响。方法研究通过检索TCGA数据库收集HNSCC患者Klotho基因、微管相关蛋白轻链3(Microtubule-associated protein light chain 3,MAPLC3)、NOP2/Sun RNA甲基转移酶2(NOP2/Sun RNA methyltransferase 2,NSUN2)的表达及随访预后资料,根据Klotho基因表达水平分为低表达组(n=87例)、中表达组(n=87例)和高表达组(n=88例)。描绘Kaplan-Meier曲线分析Klotho基因表达对临床预后的影响,同时评价Klotho基因表达与MAPLC3及NSUN2的相关性。结果不同组别患者一般临床特征资料比较差异无统计学意义(P>0.05)。高表达组患者中位总生存率(overall survival,OS)显著高于低表达组(P<0.05)。与高表达组相比,低表达组风险比为0.62(95%CI:0.44~0.87,P<0.05)。HNSCC患者中Klotho基因与MAPLC3表达水平呈正相关(r=0.19,P=0.00),而与NSUN2表达水平呈负相关(r=-0.17,P=0.00)。结论Klotho基因表达与HNSCC患者临床预后有关,同时该基因可能影响下游MAPLC3及NSUN2的表达。 展开更多
关键词 头颈鳞状细胞癌(Squamous Cell Carcinoma of Head and Neck) 预后(Prognosis) Klotho基因(Klotho Gene) 微管相关蛋白轻链3(Microtubule-associated protein light chain 3) NOP2/Sun RNA甲基转移酶2(NOP2/Sun RNA methyltransferase 2)
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Happy Feet Vietnamese footwear brand Biti’s has achieved commercial success in China through participation in the CAEXPO
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《China Report ASEAN》 2025年第9期56-56,共1页
Biti’s is one of the largest footwear manufacturers in Vietnam.Made from homegrown high-quality natural rubber,Biti’s slippers are known for their slip-resistance,durability,lightness,and breathability.In addition t... Biti’s is one of the largest footwear manufacturers in Vietnam.Made from homegrown high-quality natural rubber,Biti’s slippers are known for their slip-resistance,durability,lightness,and breathability.In addition to practicality and comfort,the products come in diverse styles at affordable prices. 展开更多
关键词 BITIS slip resistance SLIPPERS Vietnamese footwear China durability lightness high quality rubber
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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury 被引量:8
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作者 Hang Yang Yulei Xia +4 位作者 Yue Ma Mingtong Gao Shuai Hou Shanshan Xu Yanqiang Wang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1900-1918,共19页
The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically revie... The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed.Here,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion injury.We further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms.Inhibition of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury. 展开更多
关键词 calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein
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单球驱动平衡机器人运动学和动力学形式化验证
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作者 张善强 张景芝 +2 位作者 施智平 王国辉 关永 《软件学报》 北大核心 2025年第8期3462-3476,共15页
单球驱动平衡机器人是一种具有全向运动性的机器人,其灵活性能在狭小或复杂环境中得到充分体现,因此受到广泛关注.在该型机器人运动学和动力学设计过程中,保证其模型的正确性至关重要.基于测试和仿真的传统方法难以穷尽系统所有状态,因... 单球驱动平衡机器人是一种具有全向运动性的机器人,其灵活性能在狭小或复杂环境中得到充分体现,因此受到广泛关注.在该型机器人运动学和动力学设计过程中,保证其模型的正确性至关重要.基于测试和仿真的传统方法难以穷尽系统所有状态,因此可能无法捕捉到某些设计缺陷或潜在的安全风险.为确保单球驱动平衡机器人满足安全攸关机器人的正确性、安全性验证要求,在定理证明器HOL Light中,基于实分析库、矩阵分析库、机器人运动学和动力学库等定理证明库,构建单球驱动平衡机器人运动学和动力学的形式化模型,并进行高阶逻辑推导与证明. 展开更多
关键词 单球驱动平衡机器人 运动学和动力学 形式化验证 定理证明 HOL Light
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Blood diagnostic and prognostic biomarkers in amyotrophic lateral sclerosis 被引量:1
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作者 Yongting Lv Hongfu Li 《Neural Regeneration Research》 SCIE CAS 2025年第9期2556-2570,共15页
Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective d... Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited.The principal pathological alterations of the disease include the selective degeneration of motor neurons in the brain,brainstem,and spinal cord,as well as abnormal protein deposition in the cytoplasm of neurons and glial cells.The biological markers under extensive scrutiny are predominantly located in the cerebrospinal fluid,blood,and even urine.Among these biomarke rs,neurofilament proteins and glial fibrillary acidic protein most accurately reflect the pathologic changes in the central nervous system,while creatinine and creatine kinase mainly indicate pathological alterations in the peripheral nerves and muscles.Neurofilament light chain levels serve as an indicator of neuronal axonal injury that remain stable throughout disease progression and are a promising diagnostic and prognostic biomarker with high specificity and sensitivity.However,there are challenges in using neurofilament light chain to diffe rentiate amyotrophic lateral sclerosis from other central nervous system diseases with axonal injury.Glial fibrillary acidic protein predominantly reflects the degree of neuronal demyelination and is linked to non-motor symptoms of amyotrophic lateral sclerosis such as cognitive impairment,oxygen saturation,and the glomerular filtration rate.TAR DNA-binding protein 43,a pathological protein associated with amyotrophic lateral sclerosis,is emerging as a promising biomarker,particularly with advancements in exosome-related research.Evidence is currently lacking for the value of creatinine and creatine kinase as diagnostic markers;however,they show potential in predicting disease prognosis.Despite the vigorous progress made in the identification of amyotrophic lateral sclerosis biomarkers in recent years,the quest for definitive diagnostic and prognostic biomarke rs remains a formidable challenge.This review summarizes the latest research achievements concerning blood biomarkers in amyotrophic lateral sclerosis that can provide a more direct basis for the differential diagnosis and prognostic assessment of the disease beyond a reliance on clinical manifestations and electromyography findings. 展开更多
关键词 amyotrophic lateral sclerosis BIOMARKER blood biomarkers diagnosis glial fibrillary acidic protein neurofilament light chain PROGNOSIS TAR DNA-binding protein 43
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Tip-enhanced Raman scattering of glucose molecules 被引量:3
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作者 Zhonglin Xie Chao Meng +3 位作者 Donghua Yue Lei Xu Ting Mei Wending Zhang 《Opto-Electronic Science》 2025年第5期2-9,共8页
Glucose molecules are of great significance being one of the most important molecules in metabolic chain.However,due to the small Raman scattering cross-section and weak/non-adsorption on bare metals,accurately obtain... Glucose molecules are of great significance being one of the most important molecules in metabolic chain.However,due to the small Raman scattering cross-section and weak/non-adsorption on bare metals,accurately obtaining their"fingerprint information"remains a huge obstacle.Herein,we developed a tip-enhanced Raman scattering(TERS)technique to address this challenge.Adopting an optical fiber radial vector mode internally illuminates the plasmonic fiber tip to effectively suppress the background noise while generating a strong electric-field enhanced tip hotspot.Furthermore,the tip hotspot approaching the glucose molecules was manipulated via the shear-force feedback to provide more freedom for selecting substrates.Consequently,our TERS technique achieves the visualization of all Raman modes of glucose molecules within spectral window of 400-3200 cm^(-1),which is not achievable through the far-field/surface-enhanced Raman,or the existing TERS techniques.Our TERS technique offers a powerful tool for accurately identifying Raman scattering of molecules,paving the way for biomolecular analysis. 展开更多
关键词 tip-enhanced Raman scattering scanning near-field optical microscope fiber vector light field tip nanofocusing light source
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Primordial hydrogen partitioning at Earth’s core-mantle boundary:Multicomponent effects revealed by machine learning-augmented first-principles simulations 被引量:1
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作者 ZePing Jiang YuYang He ZhiGang Zhang 《Earth and Planetary Physics》 2025年第5期1001-1009,共9页
Hydrogen partitioning between liquid iron alloys and silicate melts governs its distribution and cycling in Earth’s deep interior.Existing models based on simplified Fe-H systems predict strong hydrogen sequestration... Hydrogen partitioning between liquid iron alloys and silicate melts governs its distribution and cycling in Earth’s deep interior.Existing models based on simplified Fe-H systems predict strong hydrogen sequestration into the core.However,these models do not account for the modulating effects of major light elements such as oxygen and silicon in the core during Earth’s primordial differentiation.In this study,we use first-principles molecular dynamics simulations,augmented by machine learning techniques,to quantify hydrogen chemical potentials in quaternary Fe-O-Si-H systems under early core-mantle boundary conditions(135 GPa,5000 K).Our results demonstrate that the presence of 5.2 wt%oxygen and 4.8 wt%silicon reduces the siderophile affinity of hydrogen by 35%,decreasing its alloy-silicate partition coefficient from 18.2(in the case of Fe-H)to 11.8(in the case of Fe-O-Si-H).These findings suggest that previous estimates of the core hydrogen content derived from binary system models require downward revision.Our study underscores the critical role of multicomponent interactions in core formation models and provides first-principles-derived constraints to reconcile Earth’s present-day hydrogen reservoirs with its accretionary history. 展开更多
关键词 partition coefficient HYDROGEN core-mantle differentiation light elements machine learning density functional theory
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Efficient chlorination reaction of Pt/RuO_(2)/g-C_(3)N_(4)under visible light irradiation for simultaneous removal of ammonia and bacteria from mariculture wastewater 被引量:1
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作者 Yizhan Zhang Min Zhao +2 位作者 Yida Huang Yan-Ling Hu Lei Wang 《Journal of Environmental Sciences》 2025年第4期490-502,共13页
The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by deposit... The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by depositing Pt and RuO_(2)particles onto g-C_(3)N_(4).The physicochemical properties of photocatalysts were explored by X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),X-ray diffraction(XRD),and UV–vis diffuse reflectance spectrometer(UV–vis DRS).The photocatalysts were then applied to the removal of both NH_(4)^(+)-N and bacteria from simulated mariculture wastewater.The results clarified that the removals of both NH_(4)^(+)-N and bacteria were in the sequence of g-C_(3)N_(4)<RuO_(2)/g-C_(3)N_(4)<Pt/g-C_(3)N_(4)<Pt/RuO_(2)/g-C_(3)N_(4).This magnificent photocatalytic ability of Pt/RuO_(2)/g-C_(3)N_(4)can be interpreted by the transfer of holes from g-C_(3)N_(4)to RuO_(2)to facilitate the in situ generation of HClO from Cl^(−)in wastewater,while Pt extracts photogenerated electrons for H_(2)formation to enhance the reaction.The removal of NH_(4)^(+)-N and disinfection effect were more pronounced in simulated seawater than in purewater.The removal efficiency ofNH_(4)^(+)-N increases with an increase in pH of wastewater,while the bactericidal effect was more significant under a lower pH in a pH range of 6–9.In actual seawater aquaculture wastewater,Pt/RuO_(2)/g-C_(3)N_(4)still exhibits effective removal efficiency of NH_(4)^(+)-N and bactericidal performance under sunlight.This study provides an alternative avenue for removement of NH_(4)^(+)-N and bacteria from saline waters under sunlight. 展开更多
关键词 PHOTOCATALYSIS Mariculture wastewater Ammonia nitrogen Visible light irradiation Microbial inactivation
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Reconfigurable organic ambipolar optoelectronic synaptic transistor for information security access 被引量:1
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作者 Xinqi Ma Wenbin Zhang +11 位作者 Qi Zheng Wenbiao Niu Zherui Zhao Kui Zhou Meng Zhang Shuangmei Xue Liangchao Guo Yan Yan Guanglong Ding Suting Han Vellaisamy A.L.Roy Ye Zhou 《Journal of Semiconductors》 2025年第2期133-142,共10页
In this data explosion era,ensuring the secure storage,access,and transmission of information is imperative,encom-passing all aspects ranging from safeguarding personal devices to formulating national information secu... In this data explosion era,ensuring the secure storage,access,and transmission of information is imperative,encom-passing all aspects ranging from safeguarding personal devices to formulating national information security strategies.Leverag-ing the potential offered by dual-type carriers for transportation and employing optical modulation techniques to develop high reconfigurable ambipolar optoelectronic transistors enables effective implementation of information destruction after read-ing,thereby guaranteeing data security.In this study,a reconfigurable ambipolar optoelectronic synaptic transistor based on poly(3-hexylthiophene)(P3HT)and poly[[N,N-bis(2-octyldodecyl)-napthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)](N2200)blend film was fabricated through solution-processed method.The resulting transistor exhib-ited a relatively large ON/OFF ratio of 10^(3) in both n-and p-type regions,and tunable photoconductivity after light illumination,particularly with green light.The photo-generated carriers could be effectively trapped under the gate bias,indicating its poten-tial application in mimicking synaptic behaviors.Furthermore,the synaptic plasticity,including volatile/non-volatile and excita-tory/inhibitory characteristics,could be finely modulated by electrical and optical stimuli.These optoelectronic reconfigurable properties enable the realization of information light assisted burn after reading.This study not only offers valuable insights for the advancement of high-performance ambipolar organic optoelectronic synaptic transistors but also presents innovative ideas for the future information security access systems. 展开更多
关键词 RECONFIGURABLE AMBIPOLAR OPTOELECTRONIC synaptic transistor light assisted burn after reading
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A Low Light Image Enhancement Method Based on Dehazing Physical Model 被引量:1
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作者 Wencheng Wang Baoxin Yin +2 位作者 Lei Li Lun Li Hongtao Liu 《Computer Modeling in Engineering & Sciences》 2025年第5期1595-1616,共22页
In low-light environments,captured images often exhibit issues such as insufficient clarity and detail loss,which significantly degrade the accuracy of subsequent target recognition tasks.To tackle these challenges,th... In low-light environments,captured images often exhibit issues such as insufficient clarity and detail loss,which significantly degrade the accuracy of subsequent target recognition tasks.To tackle these challenges,this study presents a novel low-light image enhancement algorithm that leverages virtual hazy image generation through dehazing models based on statistical analysis.The proposed algorithm initiates the enhancement process by transforming the low-light image into a virtual hazy image,followed by image segmentation using a quadtree method.To improve the accuracy and robustness of atmospheric light estimation,the algorithm incorporates a genetic algorithm to optimize the quadtree-based estimation of atmospheric light regions.Additionally,this method employs an adaptive window adjustment mechanism to derive the dark channel prior image,which is subsequently refined using morphological operations and guided filtering.The final enhanced image is reconstructed through the hazy image degradation model.Extensive experimental evaluations across multiple datasets verify the superiority of the designed framework,achieving a peak signal-to-noise ratio(PSNR)of 17.09 and a structural similarity index(SSIM)of 0.74.These results indicate that the proposed algorithm not only effectively enhances image contrast and brightness but also outperforms traditional methods in terms of subjective and objective evaluation metrics. 展开更多
关键词 Dark channel prior quadtree decomposition genetic algorithm atmospheric light image enhancement
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Spatial differentiation of carbon emissions from energy consumption based on machine learning algorithm:A case study during 2015–2020 in Shaanxi,China 被引量:1
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作者 Hongye Cao Ling Han +1 位作者 Ming Liu Liangzhi Li 《Journal of Environmental Sciences》 2025年第3期358-373,共16页
Carbon emissions resulting from energy consumption have become a pressing issue for governments worldwide.Accurate estimation of carbon emissions using satellite remote sensing data has become a crucial research probl... Carbon emissions resulting from energy consumption have become a pressing issue for governments worldwide.Accurate estimation of carbon emissions using satellite remote sensing data has become a crucial research problem.Previous studies relied on statistical regression models that failed to capture the complex nonlinear relationships between carbon emissions and characteristic variables.In this study,we propose a machine learning algorithm for carbon emissions,a Bayesian optimized XGboost regression model,using multi-year energy carbon emission data and nighttime lights(NTL)remote sensing data from Shaanxi Province,China.Our results demonstrate that the XGboost algorithm outperforms linear regression and four other machine learning models,with an R^(2)of 0.906 and RMSE of 5.687.We observe an annual increase in carbon emissions,with high-emission counties primarily concentrated in northern and central Shaanxi Province,displaying a shift from discrete,sporadic points to contiguous,extended spatial distribution.Spatial autocorrelation clustering reveals predominantly high-high and low-low clustering patterns,with economically developed counties showing high-emission clustering and economically relatively backward counties displaying low-emission clustering.Our findings show that the use of NTL data and the XGboost algorithm can estimate and predict carbon emissionsmore accurately and provide a complementary reference for satellite remote sensing image data to serve carbon emission monitoring and assessment.This research provides an important theoretical basis for formulating practical carbon emission reduction policies and contributes to the development of techniques for accurate carbon emission estimation using remote sensing data. 展开更多
关键词 Machine learning Energy carbon emissions Nighttime light Spatial distribution
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Development of Palygorskite-CaIn_(2)S_(4) composite for rapid Cr(Ⅵ) reduction under visible light 被引量:1
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作者 Yuanyuan Wang Shijun Jia +3 位作者 Shiqiang Ding Wenyan Zhang Rui Shu Yingfei Hu 《Journal of Environmental Sciences》 2025年第10期562-575,共14页
Using natural minerals to eliminate harmful Cr(Ⅵ)under sustainable sunshine has significant potential.Herein,Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn_(2)S_(4) photocatalysts t... Using natural minerals to eliminate harmful Cr(Ⅵ)under sustainable sunshine has significant potential.Herein,Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn_(2)S_(4) photocatalysts through a simple one-pot thermal process,enabling the efficient reduction of Cr(Ⅵ).With a Palygorskite to CaIn_(2)S_(4) mass ratio of 5%,the conversion rate of Cr(Ⅵ)reached 98%after 60min of visible-light exposure,with a remarkable reaction rate of 0.0633 min^(-1).The effective integration of CaIn_(2)S_(4) with Palygorskite led to a more uniform dispersion of CaIn_(2)S_(4),exposing more reactive sites.Moreover,the establishment of a heterojunction between CaIn_(2)S_(4) and Palygorskite facilitated the transport of photogenerated electrons from CaIn_(2)S_(4),enhancing the efficiency of charge separation.These factors contribute to the improved photocatalytic performance.Additionally,the developed composite photocatalysts demonstrated excellent stability under light exposure and could be reused efficiently.Trapping tests on active substances revealed that e-played key roles in the Cr(Ⅵ)reduction.This research suggests the potential of using natural minerals to fabricate composite photocatalysts capable of effectively removing pollutants from the environment using solar energy. 展开更多
关键词 Cr(Ⅵ)reduction Visible light PALYGORSKITE CaIn_(2)S_(4)
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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases
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作者 Lifang Zhao Mingkai Zhang +4 位作者 Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai 《Neural Regeneration Research》 SCIE CAS 2025年第8期2373-2381,共9页
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k... Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results. 展开更多
关键词 Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein NEURODEGENERATION neurofilament light chain plasma biomarkers single molecule array storage time tau
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Photoinduced Nickel-Catalyzed Reductive Heck Reaction
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作者 Liu Junjie Zhao Hongping +2 位作者 Hu Yuanyuan Wang Hengxin Yuan Weiming 《有机化学》 北大核心 2025年第5期1691-1697,共7页
An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The r... An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The reductive hydroarylation of acrylates with aryl halides was successfully achieved without requiring exogenous photoredox catalysts.This reaction is highlighted by the simple and mild conditions,good functional group tolerance,thus providing a complementary approach for alkenes reductive Heck reaction. 展开更多
关键词 NICKEL reductive Heck reaction visible light organic reductant alken
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3D Printing of Hierarchical Gyroid Hydroxyapatite-Akermanite Scaffolds with Improved Compressive Strength
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作者 HUA Shuaibin PENG Chang +4 位作者 CHENG Lijin WU Jiamin ZHANG Xiaoyan WANG Xiumei SHI Yusheng 《硅酸盐学报》 北大核心 2025年第9期2706-2717,共12页
Introduction It is necessary for an ideal bioceramic scaffold to have a suitable structure.The structure can affect the mechanical properties of the scaffold(i.e.,elastic modulus and compressive strength)and the biolo... Introduction It is necessary for an ideal bioceramic scaffold to have a suitable structure.The structure can affect the mechanical properties of the scaffold(i.e.,elastic modulus and compressive strength)and the biological properties of the scaffold(i.e.,degradability and cell growth rate).Lattice structure is a kind of periodic porous structure,which has some advantages of light weight and high strength,and is widely used in the preparation of bioceramic scaffolders.For the structure of the scaffold,high porosity and large pore size are important for bone growth,bone integration and promoting good mechanical interlocking between neighboring bones and the scaffold.However,scaffolds with a high porosity often lack mechanical strength.In addition,different parts of the bone have different structural requirements.In this paper,scaffolds with a non-uniform structure or a hierarchical structure were designed,with loose and porous exterior to facilitate cell adhesion,osteogenic differentiation and vascularization as well as relatively dense interior to provide sufficient mechanical support for bone repair.Methods In this work,composite ceramics scaffolds with 10%akermanite content were prepared by DLP technology.The scaffold had a high porosity outside to promote the growth of bone tissue,and a low porosity inside to withstand external forces.The compressive strength,fracture form,in-vitro degradation performance and bioactivity of graded bioceramic scaffolds were investigated.The models of scaffolds were imported into the DLP printer with a 405 nm light.The samples were printed with the intensity of 8 mJ/cm^(2)and a layer thickness of 50μm.Finally,the ceramic samples were sintered at 1100℃.The degradability of the hierarchical gyroid bioceramic scaffolds was evaluated through immersion in Tris-HCl solution and SBF solution at a ratio of 200 mL/g.The bioactivity of bioceramic was obtained via immersing them in SBF solution for two weeks.The concentrations of calcium,phosphate,silicon,and magnesium ions in the soaking solution were determined by an inductively coupled plasma optical emission spectrometer.Results and discussion In this work,a hierarchical Gyroid structure HA-AK10 scaffold(sintered at 1100℃)with a radial internal porosity of 50%and an external porosity of 70%is prepared,and the influence of structural form on the compressive strength and degradation performance of the scaffold is investigated.The biological activity of the bioceramics in vitro is also verified.The mechanical simulation results show that the stress distribution corresponds to the porosity distribution of the structure,and the low porosity is larger and the overall stress concentration phenomenon does not appear.After soaking in SBF solution,Si—OH is firstly formed on the surface of bioceramics,and then silicon gel layer is produced due to the presence of calcium and silicon ions.The silicon gel layer is dissociated into negatively charged groups under alkaline environment secondary adsorption of calcium ions and phosphate ions,forming amorphous calcium phosphate,and finally amorphous calcium phosphate crystals and adsorption of carbonate ions,forming carbonate hydroxyapatite.This indicates that the composite bioceramics have a good biological activity in-vitro and can provide a good environment for the growth of bone cells.A hierarchical Gyroid ceramic scaffold with a bone geometry is prepared via applying the hierarchical structure to the bone contour scaffold.The maximum load capacity of the hierarchical Gyroid ceramic scaffold is 8 times that of the uniform structure.Conclusions The hierarchical structure scaffold designed had good overall compressive performance,good degradation performance,and still maintained a good mechanical stability during degradation.In addition,in-vitro biological experimental results showed that the surface graded composite scaffold could have a good in-vitro biological activity and provide a good environment for bone cells.Compared to the heterosexual structure,the graded scaffold had greater mechanical properties. 展开更多
关键词 bioceramic scaffolds hierarchical gyroid structure compressive strength bioactivity digital light processing
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