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Research on Multi-Scale Feature Fusion Network Algorithm Based on Brain Tumor Medical Image Classification

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Computers, Materials & Continua 2024年第6期79卷 5313-5333页

作者： Yuting Zhou xuemei yang JunpingYin Shiqi Liu Graduate School China Academy of Engineering PhysicsBeijing100000China Department of Computational Mathematics Beijing Institute of Applied Physics and Computational MathematicsBeijing100000China National Key Laboratory of Computational Physics Beijing100088China Shanghai Zhangjiang Institute of Mathematics Shanghai201203China

Gliomas have the highest mortality rate of all brain tumors.Correctly classifying the glioma risk period can help doctors make reasonable treatment plans and improve patients’survival rates.This paper proposes a hierarchical multi-scale attention feature fusion medical image classification network(HMAC-Net),which effectively combines global features and local features.The network framework consists of three parallel layers:The global feature extraction layer,the local feature extraction layer,and the multi-scale feature fusion layer.A linear sparse attention mechanism is designed in the global feature extraction layer to reduce information redundancy.In the local feature extraction layer,a bilateral local attention mechanism is introduced to improve the extraction of relevant information between adjacent slices.In the multi-scale feature fusion layer,a channel fusion block combining convolutional attention mechanism and residual inverse multi-layer perceptron is proposed to prevent gradient disappearance and network degradation and improve feature representation capability.The double-branch iterative multi-scale classification block is used to improve the classification performance.On the brain glioma risk grading dataset,the results of the ablation experiment and comparison experiment show that the proposed HMAC-Net has the best performance in both qualitative analysis of heat maps and quantitative analysis of evaluation indicators.On the dataset of skin cancer classification,the generalization experiment results show that the proposed HMAC-Net has a good generalization effect.

关键词： Medical image classification feature fusion transformer

Practicing the concept of “structuring” processing in the manufacture of polymer films

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中国科学：化学英文版 2023年第4期66卷 993-1010页

作者： Tong Wu Ke Wang Xiufeng Chen xuemei yang Ming Xiang Qiang Fu State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China Shenzhen Senior Technology Material Co. Ltd.Shenzhen 518127China

Polymer processing is a technology used to transfer raw materials into products with different shapes and functionalities and is a key step for polymer application.After years of development,the polymer processing task has changed from traditional processing,which mainly addresses the specific shapes of articles and focuses on the effect of processing on the structures and properties of polymers,to modern processing,which directly transforms a“designed structure”into commercial products via processing.It is the so-called“structuring”processing.Owing to the unique long-chain nature and slow topological relaxation,polymers are always driven and frozen into different nonequilibrium conformations,providing an effective way to design a given polymer material with desired structure and tunable performances via processing.Among the endless number of processing techniques,film casting is a prototypical pathway involving high supercooling or/and a strong flow field,based on which diverse thin polymer films have been successfully developed.In this review,taking isotactic polypropylene(i PP)film as an example,we highlight the strategy of“structuring”processing,in which we transform various crystalline structures of i PP into diverse commercial film products.

关键词： structuring processing film casting dimensional uniformity crystalline structure biaxially oriented film lithium-ion batteryseparator

Genome-wide identification of endogenous retrovirus elements and their active transcription in mink genome

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微生物(英文) 2023年第2期2卷 201-208页

作者： Zheng Li Qing Wang Na Lv Guojin Xu xuemei yang Baoli Zhu CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina Jiangxi Science and Technology Normal University NanchangChina Jinan Microecological Biomedicine Shandong Laboratory JinanChina Beijing Pediatric Research Institute BeijingChina Department of Pathogenic Biology School of Basic Medical SciencesSouthwest Medical UniversityLuzhouChina

Mammalian endogenous retroviruses(ERVs)are ancient retroviruses that have been integrated into genomes.ERVs were believed to be inactive until the discovery of ERV transcription in the mouse genome.However,the transcription level and function of ERV elements in mammalian genomes are not well understood.In this study,we performed the first genome‐wide scanning of ERV loci in the American mink(Neogale vison)genome(NeoERV)followed by transcriptomic analysis to detect actively transcribed NeoERV elements.A total of 365,791 NeoERV loci were identified,and161,205(44%)of these loci were found to be actively transcribed based on transcriptomic data from three types of tissues(amygdala,trachea and lung).More than one third of the actively transcribed NeoERV loci were tissue‐specific.Furthermore,some of the active loci were associated with host gene transcription,and the level of NeoERV transcription was positively correlated with that of host genes,specifically when active loci were located in overlapped gene regions.An in‐depth analysis of the envelope protein coding env gene showed that,in general,its transcription level was higher than that of NeoERVs,which is believed to be associated with host immunity.

关键词： endogenous retrovirus mink tissue-specific transcriptome

Simple,stable and efficient nonlinear pulse compression through cascaded filamentation in air

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High Power Laser Science and Engineering 2023年第6期11卷 193-198页

作者： Tao Pu Kan Tian Bo Hu Zhongjun Wan Linzhen He xuemei yang Han Wu yang Li Weizhe Wang Houkun Liang College of Electronics and Information Engineering Sichuan UniversityChengduChina

Nonlinear compression has become an obligatory technique along with the development of ultrafast lasers in generating ultrashort pulses with narrow pulse widths and high peak power.In particular,techniques of nonlinear compression have experienced a rapid progress as ytterbium(Yb)-doped lasers with pulse widths in the range from hundreds of femtoseconds to a few picoseconds have become mainstream laser tools for both scientific and industrial applications.Here,we report a simple and stable nonlinear pulse compression technique with high efficiency through cascaded filamentation in air followed by dispersion compensation.Pulses at a center wavelength of 1040 nm with millijoule pulse energy and 160 fs pulse width from a high-power Yb:CaAlGdO_(4) regenerative amplifier are compressed to 32 fs,with only 2.4% loss from the filamentation process.The compressed pulse has a stable output power with a root-meansquare variation of 0.2% over 1 hour.

关键词： femtosecond pulse filamentation nonlinear compression

The high-quality sequencing of the Brassica rapa‘XiangQingCai’genome and exploration of genome evolution and genes related to volatile aroma

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Horticulture Research 2023年第10期10卷 174-184页

作者： Zhaokun Liu Yanhong Fu Huan Wang Yanping Zhang Jianjun Han Yingying Wang Shaoqin Shen Chunjin Li Mingmin Jiang xuemei yang Xiaoming Song Suzhou Academy of Agricultural Sciences SuzhouJiangsu 215155China College of Life Sciences North China University of Science and TechnologyTangshanHebei 063210China Suzhou Polytechnic Institute of Agriculture SuzhouJiangsu 215008China

‘Vanilla’(XQC,brassica variety chinensis)is an important vegetable crop in the Brassica family,named for its strong volatile fragrance.In this study,we report the high-quality chromosome-level genome sequence of XQC.The assembled genome length was determined as 466.11 Mb,with an N50 scaffold of 46.20 Mb.A total of 59.50%repetitive sequences were detected in the XQC genome,including 47570 genes.Among all examined Brassicaceae species,XQC had the closest relationship with B.rapa QGC(‘QingGengCai’)and B.rapa Pakchoi.Two whole-genome duplication(WGD)events and one recent whole-genome triplication(WGT)event occurred in the XQC genome in addition to an ancient WGT event.The recent WGT was observed to occur during 21.59-24.40 Mya(after evolution rate corrections).Our findings indicate that XQC experienced gene losses and chromosome rearrangements during the genome evolution of XQC.The results of the integrated genomic and transcriptomic analyses revealed critical genes involved in the terpenoid biosynthesis pathway and terpene synthase(TPS)family genes.In summary,we determined a chromosome-level genome of B.rapa XQC and identified the key candidate genes involved in volatile fragrance synthesis.This work can act as a basis for the comparative and functional genomic analysis and molecular breeding of B.rapa in the future.

关键词： evolution breeding correction

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微塑料对颗粒污泥运行效能的影响

水处理技术 2024年第3期50卷 97-102页

作者：葛红林杨雪梅山西运城农业职业技术学院山西运城044000 焦作大学化工与环境工程学院河南焦作454000

微塑料(MPs)作为新污染物的环境行为得到广泛关注。然而,MPs对好氧颗粒污泥(AGS)处理低C/N废水过程中颗粒化进程、营养盐去除规律及微生物种群特征的影响至今鲜有探究。因此,本论文以苯二甲酸乙二醇酯MPs和AGS为探究对象,在室温环境下,... 详细信息

微塑料(MPs)作为新污染物的环境行为得到广泛关注。然而,MPs对好氧颗粒污泥(AGS)处理低C/N废水过程中颗粒化进程、营养盐去除规律及微生物种群特征的影响至今鲜有探究。因此,本论文以苯二甲酸乙二醇酯MPs和AGS为探究对象,在室温环境下,探究了MPs粒径对AGS处理城镇低C/N废水的影响,并解析相关作用机制。结果表明,MPs存在加速了AGS颗粒化,提高了污泥浓度,促进了胞外聚合物(EPS)分泌,且MPs粒径越大,颗粒化进程越显著。MPs存在降低了AGS对COD和营养盐的去除,且MPs粒径越大,营养盐去除抑制越显著。MPs粒径在150μm时,COD、NH_(4)^(+)-N及TN的去除效率下降至81.6%~84.1%、82.3%~86.5%和61.6%~62.8%,均远低于空白组。MPs粒径越大,其在AGS内去除效率越低。大粒径MPs提高了Proteobacteria的相对丰度至59.6%,但降低了具有有机质分解能力的Bacteroidota的相对丰度。本论文丰富了MPs在水环境的影响行为,为日后MPs污染控制提供一定的理论依据。

关键词：微塑料好氧颗粒污泥营养盐去除 EPS 微生物群落

双污泥系统处理对典型重金属镍的响应特征及机制探究

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水处理技术 2024年第2期50卷 74-78页

作者：许亚洲杨雪梅郑州市生态环境局巩义分局河南郑州451200 焦作大学化工与环境工程学院河南焦作454000

为探究双污泥系统对典型重金属镍(Ni)的冲击负荷的响应特征及作用机制,构建了中试规模的双污泥系统,以实际废水为探究对象,研究了短期和长期暴露条件下重金属Ni对双污泥系统污染物及营养盐去除性能及微生物群落的影响。结果表明,短期暴... 详细信息

为探究双污泥系统对典型重金属镍(Ni)的冲击负荷的响应特征及作用机制,构建了中试规模的双污泥系统,以实际废水为探究对象,研究了短期和长期暴露条件下重金属Ni对双污泥系统污染物及营养盐去除性能及微生物群落的影响。结果表明,短期暴露低剂量Ni对双污泥系统去除污染物和营养盐影响不显著,但高剂量Ni(超过3.0 mg/L)降低了COD、NH4+-N及PO43--P的去除。长期暴露实验分析表明,Ni降低双污泥系统对污染物和营养盐去除。9.0 mg/L Ni导致COD、NH4+-N和PO43--P去除效率下降至64.3%、75.2%和54.2%。机制分析表明Ni降低污泥浓度,刺激胞外聚合物(EPS)主要蛋白质(PN)分泌。重金属Ni提高了乳酸脱氢酶和活性氧释放。微生物群落特征分析表明,Ni降低了Proteobacteria、Bacteroidetes、Chloroflexi、Nitrospirota的相对丰度,从而降低了微生物对污染物和营养盐的去除。本研究结果对双污泥系统处理含重金属废水提供了一定的数据支撑和理论依据。

关键词：双污泥系统重金属Ni 脱氮除磷胞外聚合物:微生物

黄河流域城市碳收支时空差异与碳补偿分区研究

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世界地理研究 2024年第3期33卷 116-130页

作者：张亚龙张海峰杨雪梅青海师范大学地理科学学院西宁810001 青海省自然地理与环境过程重点实验室西宁810001 高原科学与可持续发展研究院西宁810001 兰州文理学院旅游学院兰州730010

碳收支和碳补偿分区的研究,对于制定适应各区域低碳发展策略,推动区域生态环境协同治理,实现高质量发展具有重要意义。本文以黄河流域56个市级单元为研究区域,通过构建该流域内城市的碳收支以及碳补偿分区的概念性架构,利用集中化指数... 详细信息

碳收支和碳补偿分区的研究,对于制定适应各区域低碳发展策略,推动区域生态环境协同治理,实现高质量发展具有重要意义。本文以黄河流域56个市级单元为研究区域,通过构建该流域内城市的碳收支以及碳补偿分区的概念性架构,利用集中化指数、位置约束的多元空间聚类等方法研究黄河流域城市群碳收支的时空分异规律以及碳补偿分区,进而为城市化进程中低碳发展战略提供建设性理论方案。研究显示:(1)2000—2020年黄河流域各城市碳收支地域分异特征明显,具体来说,研究区域碳收支集中化指数围绕警戒线0.4上下浮动,且整体曲线呈明显的波动上升趋势。(2)黄河流域各城市碳收支时空差异化特征显著,数据显示,黄河流域碳排放呈现“西部低、中东部高”的结构,2000年高值中心集中在甘肃、陕西、山东三省,之后碳排放高值区逐年增多,与此同时,各城市碳汇吸收能力大致相等。(3)根据碳补偿分区框架,将研究区划分为5类碳补偿空间优化区,并为不同类型区的绿色低碳发展规划提出建议。(4)未来研究将进一步细化研究区空间尺度,探讨更小单元的碳收支与碳补偿平衡,致力于探求优化小区域的绿色低碳发展模式,以小区域的节能减排、绿色发展带动区域内城市整体实现双碳目标。

关键词：碳收支碳补偿分区集中化指数空间聚类黄河流域

盐度对好氧颗粒污泥处理畜禽养殖废水的影响机制探究

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水处理技术 2024年第6期50卷 119-124页

作者：许亚洲杨雪梅张群郑州市生态环境局巩义分局河南郑州451200 焦作大学化工与环境工程学院河南焦作454000 潍坊市青州生态环境监控中心山东潍坊262550

以好氧颗粒污泥(AGS)和畜禽养殖废水为探究对象,在室温环境下探究了盐度对AGS处理畜禽养殖废水的影响,并分析了不同盐度环境下AGS的污泥特征及微生物群落结构,揭示了相关机制。结果表明,低盐度(低于1.0 g/L)利于AGS去除污染物和营养盐,... 详细信息

以好氧颗粒污泥(AGS)和畜禽养殖废水为探究对象,在室温环境下探究了盐度对AGS处理畜禽养殖废水的影响,并分析了不同盐度环境下AGS的污泥特征及微生物群落结构,揭示了相关机制。结果表明,低盐度(低于1.0 g/L)利于AGS去除污染物和营养盐,而高浓度盐度降低了营养盐去除,提高了胞外聚合物(EPS)的分泌。当盐度为0.2 g/L时,COD、NH_(4)^(+)-N、TN和PO_(4)^(3-)-P的去除效率高达94.6%~95.2%、94.6%~96.8%、70.6%~72.1%和88.5%~92.1%,然而当盐度超过1.0 g/L,污染物及营养盐去除效率显著下降。盐度能影响AGS污泥特征,并提高蛋白质的分泌。盐度有效提高了AGS污泥沉降性。微生物学机制分析表明0.2 g/L盐度作用下AGS内与有机质降解及氮磷去除相关微生物的相对丰度提高。

关键词：畜禽养殖废水好氧颗粒污泥盐度胞外聚合物微生物群落