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Limosilactobacillus mucosae FZJTZ26M3 prevents NAFLD in mice through modulation of lipid metabolism and gut microbiota dysbiosis
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作者 Danting Dang bowen li +5 位作者 Mengfan Ding RPaul Ross Catherine Stanton Jianxin Zhao Bo Yang Wei Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1589-1601,共13页
Lactobacillus are considered promising therapeutic methods for nonalcoholic fatty liver disease(NAFLD).The effects of two strains of Ltmosilactobacillus mucosae on NAFLD were investigated in this study.Fourweek-old ma... Lactobacillus are considered promising therapeutic methods for nonalcoholic fatty liver disease(NAFLD).The effects of two strains of Ltmosilactobacillus mucosae on NAFLD were investigated in this study.Fourweek-old male C57BL/6J mice were divided into 4 groups(n=8 per group,Control,Model,FZJTZ26M3,FGSYC17L3).L.mucosae FZJTZ26M3 reduced the mice 's body weight,liver weight,and adipose tissue weight after 12 weeks of therapy.According to serum analysis,total cholesterol,triacylglycerol,and low-density lipoprotein cholesterol significantly decreased after L.mucosae FZJTZ26M3 intervention.Liver pathology showed that L.mucosae FZJTZ26M3 was effective to ameliorate lipid deposition in NAFLD mice.Additionally,the expression of the gene related to lipid metabolism in the liver and adipose tissue was analyzed,and the results indicated that L.mucosae FZJTZ26M3 could alleviate NAFLD by regulating lipid metabolism.Furthermore,the results of 16S rRNA gene sequencing revealed a drop in the relative abundance of Ruminococcaceae,which is linked to inflammation,but the relative abundance of a potential probiotic Akkermansia significantly increased after L.mucosae FZJTZ26M3 intervention.Generally,L.mucosae FZJTZ26M3 could be a candidate to prevent NAFLD. 展开更多
关键词 Limosilactobacillus mucosae Nonalcoholic fatty liver disease(NAFLD) Probiotic Lipid metabolism Gut microbiota
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The profile of sound speed and dissolved oxygen in the polymetallic nodules depositional area in the Western Pacific
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作者 bowen li Yonggang JIA +1 位作者 Zhihan FAN Kai li 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2090-2100,共11页
With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodu... With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodule mining cannot be ignored.However,duo to the lacks in stable and safe deep-sea(the depth>1000 m)vertical profile observation systems and consequently in long-term in-situ observation data,the sound speed and dissolved oxygen and the other water environment factors in the deposition areas of polymetallic nodules remains poorly understood.In this study,a deep-sea in-situ observation system was designed and deployed,and the water environment data of the polymetallic nodule deposition area were collected and analyzed.Result shows that the dissolved oxygen in the depth of 0–600 m was mainly affected by biological factors,while that in the area deeper than 600 m was affected by physical factors.The sound speed in the water body was mainly affected by temperature and pressure.At depths below 840 m,the sound speed is mainly controlled by temperature,and at depths between 840 m and 5700 m,the sound speed is mainly controlled by pressure.The correlations of sound speed vs.pressure and vs.temperature were regressed into equation.The resuspension of sediments rich in various metals may result in the reduction of dissolved oxygen and the improvement of redox potential.This environmental impact caused by a single sediment resuspension could last for 24 h or more.These findings enrich the understanding of the background value of the water environment in the polymetallic nodule deposition area. 展开更多
关键词 deep sea dissolved oxygen redox potential sound speed CONDUCTIVITY
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Controllably partial removal of thiolate ligands from unsupported Au_(25) nanoclusters by rapid thermal treatments for electrochemical CO_(2)reduction
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作者 liting Huang Yongfeng Lun +4 位作者 Yuping liu liming Chen bowen li Shuqin Song Yi Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期16-22,I0002,共8页
Colloidal synthesis of metal nanoclusters will inevitably lead to the blockage of catalytically active sites by organic ligands.Here,taking[Au_(25)(PET)_(18)]-(PET=2-phenylethanethiol)nanocluster as a model catalyst,t... Colloidal synthesis of metal nanoclusters will inevitably lead to the blockage of catalytically active sites by organic ligands.Here,taking[Au_(25)(PET)_(18)]-(PET=2-phenylethanethiol)nanocluster as a model catalyst,this work reports a feasible procedure to achieve the controllably partial removal of thiolate ligands from unsupported[Au_(25)(PET)_(18)]-nanoclusters with the preservation of the core structure.This procedure shortens the processing duration by rapid heating and cooling on the basis of traditional annealing treatment,avoiding the reconfiguration or agglomeration of Au_(25)nanoclusters,where the degree of dethiolation can be regulated by the control of duration.This work finds that a moderate degree of dethiolation can expose the Au active sites while maintaining the suppression of the competing hydrogen evolution reaction.Consequently,the activity and selectivity towards CO formation in electrochemical CO_(2)reduction reaction of Au_(25)nanoclusters can be promoted.This work provides a new approach for the removal of thiolate ligands from atomically precise gold nanoclusters. 展开更多
关键词 Gold nanoclusters THIOLATES Ligand removal Electrochemically active surface area Electrochemical CO_(2)reduction
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Surface reconstruction,modification and functionalization of natural diatomites for miniaturization of shaped heterogeneous catalysts
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作者 bowen li Tian Wang +3 位作者 Qiujian Le Runze Qin Yuxin Zhang Hua Chun Zeng 《Nano Materials Science》 EI CAS CSCD 2023年第3期293-311,共19页
Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there ... Since the discovery of mesoporous silica in 1990s,there have been numerous mesoporous silica-based nanomaterials developed for catalytic applications,aiming at enhanced catalytic activity and stability.Recently,there have also been considerable interests in endowing them with hierarchical porosities to overcome the diffusional limitation for those with long unimodal channels.Present processes of making mesoporous silica largely rely on chemical sources which are relatively expensive and impose environmental concerns on their processes.In this regard,it is desirable to develop hierarchical silica supports from natural minerals.Herein,we present a series of work on surface reconstruction,modification,and functionalization to produce diatomite-based catalysts with original morphology and macro-meso-micro porosities and to test their suitability as catalyst supports for both liquid-and gas-phase reactions.Two wet-chemical routes were developed to introduce mesoporosity to both amorphous and crystalline diatomites.Importantly,we have used computational modeling to affirm that the diatomite morphology can improve catalytic performance based on fluid dynamics simulations.Thus,one could obtain this type of catalysts from numerous natural diatoms that have inherently intricate morphologies and shapes in micrometer scale.In principle,such catalytic nanocomposites acting as miniaturized industrial catalysts could be employed in microfluidic reactors for process intensification. 展开更多
关键词 Heterogeneous catalysis Diatomites SILICA Catalytic materials MINIATURIZATION Sustainable chemistry
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CVTD: A Robust Car-Mounted Video Text Detector
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作者 Di Zhou Jianxun Zhang +2 位作者 Chao li Yifan Guo bowen li 《Computers, Materials & Continua》 SCIE EI 2024年第2期1821-1842,共22页
Text perception is crucial for understanding the semantics of outdoor scenes,making it a key requirement for building intelligent systems for driver assistance or autonomous driving.Text information in car-mounted vid... Text perception is crucial for understanding the semantics of outdoor scenes,making it a key requirement for building intelligent systems for driver assistance or autonomous driving.Text information in car-mounted videos can assist drivers in making decisions.However,Car-mounted video text images pose challenges such as complex backgrounds,small fonts,and the need for real-time detection.We proposed a robust Car-mounted Video Text Detector(CVTD).It is a lightweight text detection model based on ResNet18 for feature extraction,capable of detecting text in arbitrary shapes.Our model efficiently extracted global text positions through the Coordinate Attention Threshold Activation(CATA)and enhanced the representation capability through stacking two Feature Pyramid Enhancement Fusion Modules(FPEFM),strengthening feature representation,and integrating text local features and global position information,reinforcing the representation capability of the CVTD model.The enhanced feature maps,when acted upon by Text Activation Maps(TAM),effectively distinguished text foreground from non-text regions.Additionally,we collected and annotated a dataset containing 2200 images of Car-mounted Video Text(CVT)under various road conditions for training and evaluating our model’s performance.We further tested our model on four other challenging public natural scene text detection benchmark datasets,demonstrating its strong generalization ability and real-time detection speed.This model holds potential for practical applications in real-world scenarios. 展开更多
关键词 Deep learning text detection Car-mounted video text detector intelligent driving assistance arbitrary shape text detector
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Accurate and generalizable quantitative scoring of liver steatosis from ultrasound images via scalable deep learning 被引量:2
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作者 bowen li Dar-In Tai +8 位作者 Ke Yan Yi-Cheng Chen Cheng-Jen Chen Shiu-Feng Huang Tse-Hwa Hsu Wan-Ting Yu Jing Xiao Lu Le Adam P Harrison 《World Journal of Gastroenterology》 SCIE CAS 2022年第22期2494-2508,共15页
BACKGROUND Hepatic steatosis is a major cause of chronic liver disease.Two-dimensional(2D)ultrasound is the most widely used non-invasive tool for screening and monitoring,but associated diagnoses are highly subjectiv... BACKGROUND Hepatic steatosis is a major cause of chronic liver disease.Two-dimensional(2D)ultrasound is the most widely used non-invasive tool for screening and monitoring,but associated diagnoses are highly subjective.AIM To develop a scalable deep learning(DL)algorithm for quantitative scoring of liver steatosis from 2D ultrasound images.METHODS Using multi-view ultrasound data from 3310 patients,19513 studies,and 228075 images from a retrospective cohort of patients received elastography,we trained a DL algorithm to diagnose steatosis stages(healthy,mild,moderate,or severe)from clinical ultrasound diagnoses.Performance was validated on two multiscanner unblinded and blinded(initially to DL developer)histology-proven cohorts(147 and 112 patients)with histopathology fatty cell percentage diagnoses and a subset with FibroScan diagnoses.We also quantified reliability across scanners and viewpoints.Results were evaluated using Bland-Altman and receiver operating characteristic(ROC)analysis.RESULTS The DL algorithm demonstrated repeatable measurements with a moderate number of images(three for each viewpoint)and high agreement across three premium ultrasound scanners.High diagnostic performance was observed across all viewpoints:Areas under the curve of the ROC to classify mild,moderate,and severe steatosis grades were 0.85,0.91,and 0.93,respectively.The DL algorithm outperformed or performed at least comparably to FibroScan control attenuation parameter(CAP)with statistically significant improvements for all levels on the unblinded histology-proven cohort and for“=severe”steatosis on the blinded histology-proven cohort.CONCLUSION The DL algorithm provides a reliable quantitative steatosis assessment across view and scanners on two multi-scanner cohorts.Diagnostic performance was high with comparable or better performance than the CAP. 展开更多
关键词 ULTRASOUND Liver steatosis Deep learning SCREENING Computer-aided diagnosis
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The controlling factors of high suspended sediment concentration in the intertidal flat off the Huanghe River Estuary 被引量:1
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作者 bowen li Yonggang Jia +3 位作者 J.Paul liu Jianfeng Su Xiaolei liu Mingzheng Wen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第10期96-106,共11页
The Huanghe River(Yellow River)is known by its high suspended sediment concentration(SSC)in its river mouth tidal flat.However,the factors controlling the high SSC over there are not well understood.Therefore,we condu... The Huanghe River(Yellow River)is known by its high suspended sediment concentration(SSC)in its river mouth tidal flat.However,the factors controlling the high SSC over there are not well understood.Therefore,we conducted 7-d hydrodynamic observations(water depth,wave height,and current velocity)and SSC measurements on the tidal flat off the Huanghe River Mouth.The data shows that in most of time,under the calm sea condition,the SSC ranges 0.1–3.5 g/L,and sediment discharge from the river is the main source.However,when hydrodynamics are enhanced in a tidal cycle and large-scale erosion occurs on the seafloor,resuspended sediment becomes the main source,and the SSC in the water column reaches 17.3 g/L.We find the suspended sediment flux is mainly controlled by the tidal current and Stokes drift,while the wave-induced shear stress could also affect the variation of suspended sediment flux.During the observation period,when sea under calm-rippled conditions,the current-induced resuspended sediment concentration(RSC)was greater than the wave-induced RSC.In contrast,in smooth-wavelet sea conditions,the wave-induced RSC was greater than the current-induced RSC,for instance,a single wave event was found to cause 11.8 cm seabed erosion within 6 h.This study reveals different controlling factors for the high SSC near a river-influenced tidal flat,and helps us get a better understanding of a delta's depositional and erosional mechanisms. 展开更多
关键词 Huanghe River(Yellow River) sediment re-suspension sediment transport WAVE CURRENT in-situ observation
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Simulation of Multi-satellite GNSS Reflected Signals and Design of Simulator 被引量:4
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作者 bowen li Dongkai YANG Bo ZHANG 《Journal of Geodesy and Geoinformation Science》 2021年第2期36-46,共11页
Using GNSS-R technology for remote sensing of surface parameters has become a new trend in the field of remote sensing.With the rapid development of GNSS-R technology,GNSS-R simulation has become one of the new hot sp... Using GNSS-R technology for remote sensing of surface parameters has become a new trend in the field of remote sensing.With the rapid development of GNSS-R technology,GNSS-R simulation has become one of the new hot spots.Now the researches of the GNSS-R simulation are all the simulations that consider a single star or a single frequency point,and in actual applications,the signal captured by the receiver is often the reflected signals of multiple stars.In view of this situation,from the perspective of multi-satellite simulation,this paper gives the model of GNSS-R multi-satellite ocean simulation on the basis of analyzing the remote sensing principle,reflection signal model and simulation principle of GNSS-R technology.Based on the GNSS-R multi-satellite ocean simulation model and the fast parallel computing capability of GPU,the GNSS-R multi-satellite ocean simulator was designed.Finally,the direct and reflected signals generated by the GNSS-R multi-satellite simulator were tested and verified.The results show that the positioning result of the direct signal meets the positioning accuracy requirements;The delay-related power results obtained from the simulated two-satellite reflected signals processing are in good agreement with the theoretical model,and the correlation coefficients are all above 0.99;The generated signals are used for GNSS-R height measurement technology,the height measurement error is about 1.4~1.8 m,which is in line with the accuracy of the C/A code ranging receiver;And the parallel operation of the GPU for multi-satellite simulation calculation is 800—900 times higher than the traditional CPU calculation.It proves that the proposed model and the designed simulator are feasible and accurate. 展开更多
关键词 GNSS reflected signals multi-satellite simulation simulator design
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Large Rabi splitting obtained in Ag‐WS2 strong‐coupling heterostructure with optical microcavity at room temperature
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作者 bowen li Shuai Zu +11 位作者 Zhepeng Zhang liheng Zheng Qiao Jiang bowen Du Yang Luo Yongji Gong Yanfeng Zhang Feng lin Bo Shen Xing Zhu Pulickel M. Ajayan Zheyu Fang 《Opto-Electronic Advances》 2019年第5期1-9,共9页
Manipulation of light-matter interaction is critical in modern physics, especially in the strong coupling regime, where the generated half-light, half-matter bosonic quasiparticles as polaritons are important for fund... Manipulation of light-matter interaction is critical in modern physics, especially in the strong coupling regime, where the generated half-light, half-matter bosonic quasiparticles as polaritons are important for fundamental quantum science and applications of optoelectronics and nonlinear optics. Two-dimensional transition metal dichalcogenides (TMDs) are ideal platforms to investigate the strong coupling because of their huge exciton binding energy and large absorption coefficients. Further studies on strong exciton-plasmon coupling by combining TMDs with metallic nanostructures have generated broad interests in recent years. However, because of the huge plasmon radiative damping, the observation of strong coupling is significantly limited at room temperature. Here, we demonstrate that a large Rabi splitting (~300 meV) can be achieved at ambient conditions in the strong coupling regime by embedding Ag-WS2 heterostructure in an optical microcavity. The generated quasiparticle with part-plasmon, part-exciton and part-light is analyzed with Hopfield coefficients that are calculated by using three-coupled oscillator model. The resulted plasmon-exciton polaritonic hybrid states can efficiently enlarge the obtained Rabi splitting, which paves the way for the practical applications of polaritonic devices based on ultrathin materials. 展开更多
关键词 RABI SPLITTING STRONG COUPLING transition metal DICHALCOGENIDES optical microcavity surface PLASMONS
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下呼吸道及肺癌内菌群与肺癌发生发展的关系及其临床应用
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作者 李博文 黄志诚 +6 位作者 王亚东 薛剑超 夏研凯 徐源 杨华夏 梁乃新 李单青 《中国肺癌杂志》 CAS CSCD 北大核心 2023年第12期950-956,共7页
由于16S rRNA测序技术的发展,长期以来被认为是不存在的下呼吸道菌群也逐步被揭示出来。这些微生物与疾病(如肿瘤)的相关性是近年来的研究热点。由于肿瘤周围环境中的菌群会进入肿瘤内部,研究者们也开始关注肿瘤内菌群的生物学行为以及... 由于16S rRNA测序技术的发展,长期以来被认为是不存在的下呼吸道菌群也逐步被揭示出来。这些微生物与疾病(如肿瘤)的相关性是近年来的研究热点。由于肿瘤周围环境中的菌群会进入肿瘤内部,研究者们也开始关注肿瘤内菌群的生物学行为以及其与肿瘤的相互作用。在这篇综述中,我们展示了下呼吸道菌群的特点,并总结了近年来关于这些菌群与肺癌关系的相关研究成果。同时,我们也对肿瘤内菌群的基本特征进行整理,并着重阐述肺癌内菌群的特点及其与肺癌发生、发展的关系。最后,我们综述了下呼吸道和肺癌内菌群在临床上的转化应用方向,并汇总了样本采集、测序和控制污染的要点,希望为肿瘤的早筛和治疗提供新的思路。 展开更多
关键词 肺肿瘤 呼吸系统 细菌
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熔融共混一步法制备具有优异水氧阻隔性能的苯乙烯-甲基丙烯酸甲酯共聚物量子点扩散板
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作者 李博文 段宇豪 +3 位作者 葛伟新 朱家铭 熊英 郭少云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第4期122-128,共7页
为了同时增强苯乙烯-甲基丙烯酸甲酯共聚物(SMMA)的光扩散性能和水氧阻隔性能,首次将阻隔性能优异的乙烯-乙烯醇共聚物(EVOH)作为光扩散粒子,通过简单的熔融共混法制备了不同EVOH含量的SMMA/EVOH复合材料。采用扫描电子显微镜、透光率... 为了同时增强苯乙烯-甲基丙烯酸甲酯共聚物(SMMA)的光扩散性能和水氧阻隔性能,首次将阻隔性能优异的乙烯-乙烯醇共聚物(EVOH)作为光扩散粒子,通过简单的熔融共混法制备了不同EVOH含量的SMMA/EVOH复合材料。采用扫描电子显微镜、透光率雾度仪、气体渗透仪、水蒸气透过率测试仪等详细研究了复合材料的微观结构、光扩散性能、水氧阻隔性能、力学性能以及量子点荧光强度的变化。研究结果表明,EVOH与SMMA不完全相容,质量分数40%以下的EVOH在SMMA体系中以球形分散相形式存在,可将雾度从纯SMMA的0.3%提高至80%以上,起到光散射粒子的作用,透光率依然保持在60%以上;随着EVOH含量增加,复合材料的拉伸力学性能呈现先增加后降低的趋势,但水氧阻隔性能逐渐提高。将量子点加入阻隔扩散板中,能够有效延长量子点的荧光寿命,具有较强的应用价值。 展开更多
关键词 苯乙烯-甲基丙烯酸甲酯共聚物 乙烯-乙烯醇共聚物 荧光寿命 水氧阻隔性能 量子点扩散板
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Managing the immune microenvironment of osteosarcoma:the outlook for osteosarcoma treatment 被引量:3
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作者 Hailong Tian Jiangjun Cao +4 位作者 bowen li Edouard CNice Haijiao Mao Yi Zhang Canhua Huang 《Bone Research》 SCIE CAS CSCD 2023年第1期21-46,共26页
Osteosarcoma,with poor survival after metastasis,is considered the most common primary bone cancer in adolescents.Notwithstanding the efforts of researchers,its five-year survival rate has only shown limited improveme... Osteosarcoma,with poor survival after metastasis,is considered the most common primary bone cancer in adolescents.Notwithstanding the efforts of researchers,its five-year survival rate has only shown limited improvement,suggesting that existing therapeutic strategies are insufficient to meet clinical needs.Notably,immunotherapy has shown certain advantages over traditional tumor treatments in inhibiting metastasis.Therefore,managing the immune microenvironment in osteosarcoma can provide novel and valuable insight into the multifaceted mechanisms underlying the heterogeneity and progression of the disease.Additionally,given the advances in nanomedicine,there exist many advanced nanoplatforms for enhanced osteosarcoma immunotherapy with satisfactory physiochemical characteristics.Here,we review the classification,characteristics,and functions of the key components of the immune microenvironment in osteosarcoma.This review also emphasizes the application,progress,and prospects of osteosarcoma immunotherapy and discusses several nanomedicine-based options to enhance the efficiency of osteosarcoma treatment.Furthermore,we examine the disadvantages of standard treatments and present future perspectives for osteosarcoma immunotherapy. 展开更多
关键词 OSTEOSARCOMA METASTASIS TREATMENT
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Oral squamous cell carcinomas:state of the field and emerging directions 被引量:2
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作者 Yunhan Tan Zhihan Wang +6 位作者 Mengtong Xu bowen li Zhao Huang Siyuan Qin Edouard C.Nice Jing Tang Canhua Huang 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第4期552-574,共23页
Oral squamous cell carcinoma (OSCC) develops on the mucosal epithelium of the oral cavity. It accounts for approximately 90% oforal malignancies and impairs appearance, pronunciation, swallowing, and flavor perception... Oral squamous cell carcinoma (OSCC) develops on the mucosal epithelium of the oral cavity. It accounts for approximately 90% oforal malignancies and impairs appearance, pronunciation, swallowing, and flavor perception. In 2020, 377,713 OSCC cases werereported globally. According to the Global Cancer Observatory (GCO), the incidence of OSCC will rise by approximately 40% by2040, accompanied by a growth in mortality. Persistent exposure to various risk factors, including tobacco, alcohol, betel quid (BQ),and human papillomavirus (HPV), will lead to the development of oral potentially malignant disorders (OPMDs), which are oralmucosal lesions with an increased risk of developing into OSCC. Complex and multifactorial, the oncogenesis process involvesgenetic alteration, epigenetic modification, and a dysregulated tumor microenvironment. Although various therapeuticinterventions, such as chemotherapy, radiation, immunotherapy, and nanomedicine, have been proposed to prevent or treat OSCCand OPMDs, understanding the mechanism of malignancies will facilitate the identification of therapeutic and prognostic factors,thereby improving the efficacy of treatment for OSCC patients. This review summarizes the mechanisms involved in OSCC.Moreover, the current therapeutic interventions and prognostic methods for OSCC and OPMDs are discussed to facilitatecomprehension and provide several prospective outlooks for the fields. 展开更多
关键词 DIRECTIONS thereby globally
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九寨沟优势植物凋落物叶片淋溶的碳氮磷释放特征 被引量:6
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作者 张婷 代群威 +5 位作者 邓远明 李琼芳 董发勤 bowen li Bruce WFouke 李相邑 《中国岩溶》 CAS CSCD 北大核心 2021年第1期133-139,共7页
通过对九寨沟水体中两种优势植物落叶的碳氮磷淋溶动态分析发现:初期总溶解碳氮磷释放在48 h内逐渐稳定,表明短期的淋溶过程就可以导致较大比例的元素释放;磷的短期平均可溶出比例为29.61%,表明淋溶是植物磷元素释放的重要途径;估算得... 通过对九寨沟水体中两种优势植物落叶的碳氮磷淋溶动态分析发现:初期总溶解碳氮磷释放在48 h内逐渐稳定,表明短期的淋溶过程就可以导致较大比例的元素释放;磷的短期平均可溶出比例为29.61%,表明淋溶是植物磷元素释放的重要途径;估算得出九寨沟植物叶片碳氮磷贡献总量分别可达20577 t∙a^(-1),2101 t∙a^(-1),1402 t∙a^(-1)。研究表明九寨沟植物凋落物淋溶是水体碳氮磷的重要来源,也是影响钙华沉积的重要因素。分析凋落物养分溶出特征,可为九寨沟生态系统的健康发展提供数据支撑。 展开更多
关键词 凋落物叶片 淋溶 碳氮磷释放 钙华沉积 九寨沟
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Measuring tree stem diameters and straightness with depth-image computer vision
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作者 Hoang Tran Keith Woeste +2 位作者 bowen li Akshat Verma Guofan Shao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1395-1405,共11页
Current techniques of forest inventory rely on manual measurements and are slow and labor intensive.Recent developments in computer vision and depth sensing can produce accurate measurement data at significantly reduc... Current techniques of forest inventory rely on manual measurements and are slow and labor intensive.Recent developments in computer vision and depth sensing can produce accurate measurement data at significantly reduced time and labor costs.We developed the ForSense system to measure the diameters of trees at various points along the stem as well as stem straightness.Time use,mean absolute error(MAE),and root mean squared error(RMSE)metrics were used to compare the system against manual methods,and to compare the system against itself(reproducibility).Depth-derived diameter measurements of the stems at the heights of 0.3,1.4,and 2.7 m achieved RMSE of 1.7,1.5,and 2.7 cm,respectively.The ForSense system produced straightness measurement data that was highly correlated with straightness ratings by trained foresters.The ForSense system was also consistent,achieving sub-centimeter diameter difference with subsequent measures and less than 4%difference in straightness value between runs.This method of forest inventory,which is based on depth-image computer vision,is time efficient compared to manual methods and less computationally and technologically intensive compared to Structure-from-Motion(SFM)photogrammetry and ground-based LiDAR or terrestrial laser scanning(TLS). 展开更多
关键词 Forest inventory Depth sensing Computer vision Tree diameter Stem straightness Trunk volume
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Electron-impact ionization of W^(9+)and W^(10+)
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作者 鲍润家 魏军奎 +2 位作者 陈雷 李博文 陈熙萌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期226-235,共10页
Electron-impact single-ionization(EISI)cross sections for W^(q+)(q=9,10)ions have been calculated by using the level-to-level distorted-wave(LLDW)method with emphasis on the contribution of metastable states to the to... Electron-impact single-ionization(EISI)cross sections for W^(q+)(q=9,10)ions have been calculated by using the level-to-level distorted-wave(LLDW)method with emphasis on the contribution of metastable states to the total ionization cross sections.Contributions from direct-ionization(DI)and excitation-autoionization(EA)processes are taken into account.The calculated cross sections include the contributions from both the ground configuration and the long-lived metastable states with lifetimes exceeding 10^(-6)s.Calculated cross sections are in good agreement with experimental measurements when the influence of metastable states on the total ionization cross section are well considered. 展开更多
关键词 tungsten ions electron-impact ionization relativistic distorted-wave method metastable states
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Combination therapy to overcome ferroptosis resistance by biomimetic self-assembly nano-prodrug
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作者 Yong Huang Yi lin +7 位作者 bowen li Fu Zhang Chenyue Zhan Xin Xie Zhuo Yao Chongzhi Wu Yuan Ping Jianliang Shen 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第5期99-111,共13页
Ferroptosis has emerged as a potent form of no-apoptotic cell death that offers a promising alternative to avoid the chemoresistance of apoptotic pathways and serves as a vulnerability of cancer.Herein,we have constru... Ferroptosis has emerged as a potent form of no-apoptotic cell death that offers a promising alternative to avoid the chemoresistance of apoptotic pathways and serves as a vulnerability of cancer.Herein,we have constructed a biomimetic self-assembly nano-prodrug system that enables the co-delivery of gefitinib(Gefi),ferrocene(Fc)and dihydroartemisinin(DHA)for the combined therapy of both ferroptosis and apoptosis.In the tumor microenvironment,this nano-prodrug is able to disassemble and trigger drug release under high levels of GSH.Interestingly,the released DHA can downregulate GPX4 level for the enhancement of intracellular ferroptosis from Fc,further executing tumor cell death with concomitant chemotherapy by Gefi.More importantly,this nano-prodrug provides highly homologous targeting ability by coating related cell membranes and exhibits outstanding inhibition of tumor growth and metastasis,as well as no noticeable side-effects during treatments.This simple small molecular self-assembled nano-prodrug provides a new reasonably designed modality for ferroptosis-combined chemotherapy. 展开更多
关键词 Self-assembly nano-prodrug Ferroptosis APOPTOSIS Combination therapy
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A New Method for Image Tamper Detection Based on an Improved U-Net
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作者 Jie Zhang Jianxun Zhang +2 位作者 bowen li Jie Cao Yifan Guo 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2883-2895,共13页
With the improvement of image editing technology,the threshold of image tampering technology decreases,which leads to a decrease in the authenticity of image content.This has also driven research on image forgery dete... With the improvement of image editing technology,the threshold of image tampering technology decreases,which leads to a decrease in the authenticity of image content.This has also driven research on image forgery detection techniques.In this paper,a U-Net with multiple sensory field feature extraction(MSCU-Net)for image forgery detection is proposed.The proposed MSCU-Net is an end-to-end image essential attribute segmentation network that can perform image forgery detection without any pre-processing or post-processing.MSCU-Net replaces the single-scale convolution module in the original network with an improved multiple perceptual field convolution module so that the decoder can synthesize the features of different perceptual fields use residual propagation and residual feedback to recall the input feature information and consolidate the input feature information to make the difference in image attributes between the untampered and tampered regions more obvious,and introduce the channel coordinate confusion attention mechanism(CCCA)in skip-connection to further improve the segmentation accuracy of the network.In this paper,extensive experiments are conducted on various mainstream datasets,and the results verify the effectiveness of the proposed method,which outperforms the state-of-the-art image forgery detection methods. 展开更多
关键词 Forgery detection multiple receptive fields cyclic residuals U-Net channel coordinate confusion attention
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Acquiring Weak Annotations for Tumor Localization in Temporal and Volumetric Data
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作者 Yu-Cheng Chou bowen li +2 位作者 Deng-Ping Fan Alan Yuille Zongwei Zhou 《Machine Intelligence Research》 EI CSCD 2024年第2期318-330,共13页
Creating large-scale and well-annotated datasets to train AI algorithms is crucial for automated tumor detection and localization.However,with limited resources,it is challenging to determine the best type of annotati... Creating large-scale and well-annotated datasets to train AI algorithms is crucial for automated tumor detection and localization.However,with limited resources,it is challenging to determine the best type of annotations when annotating massive amounts of unlabeled data.To address this issue,we focus on polyps in colonoscopy videos and pancreatic tumors in abdominal CT scans;Both applications require significant effort and time for pixel-wise annotation due to the high dimensional nature of the data,involving either temporary or spatial dimensions.In this paper,we develop a new annotation strategy,termed Drag&Drop,which simplifies the annotation process to drag and drop.This annotation strategy is more efficient,particularly for temporal and volumetric imaging,than other types of weak annotations,such as per-pixel,bounding boxes,scribbles,ellipses and points.Furthermore,to exploit our Drag&Drop annotations,we develop a novel weakly supervised learning method based on the watershed algorithm.Experimental results show that our method achieves better detection and localization performance than alternative weak annotations and,more importantly,achieves similar performance to that trained on detailed per-pixel annotations.Interestingly,we find that,with limited resources,allocating weak annotations from a diverse patient population can foster models more robust to unseen images than allocating per-pixel annotations for a small set of images.In summary,this research proposes an efficient annotation strategy for tumor detection and localization that is less accurate than per-pixel annotations but useful for creating large-scale datasets for screening tumors in various medical modalities. 展开更多
关键词 Weak annotation detection localization segmentation COLONOSCOPY ABDOMEN
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Morphology-dependent activation of hydrogen peroxide with Cu_(2)O for tetracycline hydrochloride degradation in bicarbonate aqueous solution
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作者 Xiuying liu Qianna Xia +6 位作者 Jiao Zhou bowen li Shuaiqi Zhao Long Chen Aimal Khan Xiaoxia li Aihua Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期567-579,共13页
The design of efficient heterogeneous catalysts in bicarbonate-activated hydrogen peroxide systems(BAP)is a hot topic in wastewater treatment.In this work,Cu_(2)O nanoparticles with different morphologies including cu... The design of efficient heterogeneous catalysts in bicarbonate-activated hydrogen peroxide systems(BAP)is a hot topic in wastewater treatment.In this work,Cu_(2)O nanoparticles with different morphologies including cubic shape(c-Cu_(2)O),octahedron shape(o-Cu_(2)O)and spherical shape(s-Cu_(2)O),were applied in BAP for the first time to degrade tetracycline hydrochloride(TC).Compared with Cu^(2+)ions and CuO,TC degradation was boosted in the presence of Cu_(2)O in the BAP system,with the degradation rate following the order c-Cu_(2)O>o-Cu_(2)O>s-Cu_(2)O.The morphology-dependent effects could be linearly correlated with the ratio of surface oxygen species(O_S),but not with the surface area or Cu(Ⅰ)ratio.The c-Cu_(2)O catalyst with exposure of(100)facets contained 76.6%O_Sas the active site for H_(2)O_(2)adsorption and activation,while the value was much lower for o-Cu_(2)O and s-Cu_(2)O with dominant(111)facets.The presence of HCO_(3)-enhanced the interactions among Cu_(2)O,H_(2)O_(2)and TC,leading to facile oxidation of Cu(Ⅰ)to Cu(Ⅱ)by H_(2)O_(2),and the formation of various reactive species such as hydroxyl radicals and Cu(Ⅲ)contributed to TC degradation.This work provides a new method for enhancing H_(2)O_(2)activation with heterogeneous catalysts by crystal facet engineering. 展开更多
关键词 Hydrogen peroxide BICARBONATE Cu_(2)O Morphology-dependent effects
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