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弱Hopf代数上的弱Alternative Doi-Hopf模
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作者 贾玲 李方 《数学物理学报(A辑)》 CSCD 北大核心 2008年第6期1067-1076,共10页
该文首先引入了弱Hopf代数上的弱Alternative Doi—Hopf模,然后构造了从弱Alter—native Doi-Hopf模范畴到模范畴(余模范畴)忘却函子的伴随函子.
关键词 HOPF代数 弱alternative Doi—Hopf模
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Alternative splicing of the PECTINESTERASE gene encoding a cell wall-degrading enzyme affects postharvest softening in grape
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作者 Hainan Liu Maosong Pei +5 位作者 Charles Ampomah-Dwamena Yaxin Shang Yihe Yu Tonglu Wei Qiaofang Shi Dalong Guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期863-875,共13页
The firmness of table grape berries is a crucial quality parameter. Despite extensive research on postharvest fruit softening, its precise molecular mechanisms remain elusive. To enhance our comprehension of the under... The firmness of table grape berries is a crucial quality parameter. Despite extensive research on postharvest fruit softening, its precise molecular mechanisms remain elusive. To enhance our comprehension of the underlying molecular factors, we initially identified differentially expressed genes(DEGs) by comparing the transcriptomes of folic acid(FA)-treated and water-treated(CK) berries at different time points. We then analyzed the sequences to detect alternatively spliced(AS) genes associated with postharvest softening. A total of 2,559 DEGs were identified and categorized into four subclusters based on their expression patterns, with subcluster-4 genes exhibiting higher expression in the CK group compared with the FA treatment group. There were 1,045 AS-associated genes specific to FA-treated berries and 1,042 in the CK-treated berries, respectively. Gene Ontology(GO) annotation indicated that the AS-associated genes in CK-treated berries were predominantly enriched in cell wall metabolic processes,particularly cell wall degradation processes. Through a comparison between treatment-associated AS genes and subcluster-4 DEGs, we identified eight genes, including Pectinesterase 2(VvPE2, Vitvi15g00704), which encodes a cell wall-degrading enzyme and was predicted to undergo an A3SS event. The reverse transcription polymerase chain reaction further confirmed the presence of a truncated transcript variant of VvPE2 in the FA-treated berries.Our study provides a comprehensive analysis of AS events in postharvest grape berries using transcriptome sequencing and underscores the pivotal role of VvPE2 during the postharvest storage of grape berries. 展开更多
关键词 GRAPE postharvest softening folic acid alternative splicing Pectinesterase 2 alternative 3'splice site(A3SS)
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A Neural-network-based Alternative Scheme to Include Nonhydrostatic Processes in an Atmospheric Dynamical Core
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作者 Yang XIA Bin WANG +13 位作者 Lijuan LI Li LIU Jianghao LI Li DONG Shiming XU Yiyuan LI Wenwen XIA Wenyu HUANG Juanjuan LIU Yong WANG Hongbo LIU Ye PU Yujun HE Kun XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1083-1099,I0002,I0003,共19页
Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostat... Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostatic solver in an atmospheric dynamical core.The NAS is designed to replace this solver,which can be incorporated into any hydrostatic models so that existing well-developed hydrostatic models can effectively serve for a longer time.Recent advances in machine learning(ML)provide a potential tool for capturing the main complicated nonlinear-nonhydrostatic relationship.In this study,an ML approach called a neural network(NN)was adopted to select leading input features and develop the NAS.The NNs were trained and evaluated with 12-day simulation results of dry baroclinic-wave tests by the Weather Research and Forecasting(WRF)model.The forward time difference of the nonhydrostatic tendency was used as the target variable,and the five selected features were the nonhydrostatic tendency at the last time step,and four hydrostatic variables at the current step including geopotential height,pressure in two different forms,and potential temperature,respectively.Finally,a practical NAS was developed with these features and trained layer by layer at a 20-km horizontal resolution,which can accurately reproduce the temporal variation and vertical distribution of the nonhydrostatic tendency.Corrected by the NN-based NAS,the improved hydrostatic solver at different horizontal resolutions can run stably for at least one month and effectively reduce most of the nonhydrostatic errors in terms of system bias,anomaly root-mean-square error,and the error of the wave spatial pattern,which proves the feasibility and superiority of this scheme. 展开更多
关键词 neural network nonhydrostatic alternative scheme atmospheric model dynamical core
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Improved genome annotation of Brassica oleracea highlights the importance of alternative splicing
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作者 Yinqing Yang Lei Zhang +7 位作者 Qi Tang Lingkui Zhang Xing Li Shumin Chen Kang Zhang Ying Li Xilin Hou Feng Cheng 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期961-970,共10页
Brassica oleracea has been developed into many important crops,including cabbage,kale,cauliflower,broccoli and so on.The genome and gene annotation of cabbage(cultivar JZS),a representative morphotype of B.oleracea,ha... Brassica oleracea has been developed into many important crops,including cabbage,kale,cauliflower,broccoli and so on.The genome and gene annotation of cabbage(cultivar JZS),a representative morphotype of B.oleracea,has been widely used as a common reference in biological research.Although its genome assembly has been updated twice,the current gene annotation still lacks information on untranslated regions(UTRs)and alternative splicing(AS).Here,we constructed a high-quality gene annotation(JZSv3)using a full-length transcriptome acquired by nanopore sequencing,yielding a total of 59452 genes and 75684 transcripts.Additionally,we re-analyzed the previously reported transcriptome data related to the development of different tissues and cold response using JZSv3 as a reference,and found that 3843 out of 11908 differentially expressed genes(DEGs)underwent AS during the development of different tissues and 309 out of 903 cold-related genes underwent AS in response to cold stress.Meanwhile,we also identified many AS genes,including BolLHCB5 and BolHSP70,that displayed distinct expression patterns within variant transcripts of the same gene,highlighting the importance of JZSv3 as a pivotal reference for AS analysis.Overall,JZSv3 provides a valuable resource for exploring gene function,especially for obtaining a deeper understanding of AS regulation mechanisms. 展开更多
关键词 Brassica oleracea Oxford nanopore technologies Gene annotation alternative splicing
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2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-Glucoside modulates CHEK2 and CCND1 alternative splicing to inhibit MCF-7 cells proliferation
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作者 Hui Shen You-Zhi Zhang +5 位作者 Peng-Yu Wang Shuo Zhang Huan Pan Bei-Bei Liu Long-Sheng Xu Jian-Fen Shen 《Traditional Medicine Research》 2024年第1期33-46,共14页
Background:In our previous study,we observed a synergistic effect of 2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-glucoside combined with adriamycin to induce apoptosis in MCF-7 breast cancer cells.However,the underlying me... Background:In our previous study,we observed a synergistic effect of 2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-glucoside combined with adriamycin to induce apoptosis in MCF-7 breast cancer cells.However,the underlying mechanisms of epigenetic modifications,such as alternative splicing,have not been explored.In this study,we aimed to investigate the mechanism by which THSG inhibits MCF-7 cell proliferation using full-length transcriptome sequencing.Methods:First,cell viability was examined using the methyl thiazolyl tetrazolium method and full-length transcriptome sequencing was performed to identify genes and pathways.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to identify the principal pathways and targets of THSG.Flow cytometry analysis of cell cycle distribution was performed.Meanwhile,the analysis of alternative splicing and domains of the key proteins was conducted.Quantitative polymerase chain reaction and western blotting were performed for verification.Results:THSG showed significant cytotoxic activity in MCF-7 cells.Full-length transcriptome sequencing revealed differential alternative splicing with 173 upregulated and 263 downregulated genes.Further analysis identified distinct differential expression of genes(CHEK2-211 and CCND1-201)involved in the cell cycle in the THSG-treated group.Subsequently,alternative splicing types of CHEK2(mutually exclusive exon)and CCND1(intron retention).We found that THSG downregulated mRNA expression,as confirmed by quantitative polymerase chain reaction analysis.Interestingly,protein structural analysis revealed that THSG treatment led to the generation of CHK2-211,which was the result of a mutation in the amino acid residues(GLU-150,ASN-151)of the CHEK2 domain(VAL-150,GLY-151).and CyclinD1-201 were obtained when an amino acid(ASP-267)in the domain was lost in CyclinD1.Moreover,molecular docking analysis demonstrated that the domains of key proteins could bind THSG more effectively,with no difference in affinity.Western blotting confirmed that THSG inhibited the expression of CHK2 and CyclinD1.Conclusion:THSG modulated the alternative splicing of CHEK2 and CCND1 by inducing G0/G1 cell cycle arrest,consequently suppressing MCF-7 cell proliferation. 展开更多
关键词 THSG breast cancer full-length transcriptome sequencing alternative splicing
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Workshop “Navigating the Transition: Standards Powering the Journey of Alternative Fuel Infrastructure”
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《China Standardization》 2024年第2期67-67,共1页
April 18, Brussels, Belgium In light of recent significant regulatory changes within the European Union impacting the transport sector, such as the Alternative Fuels Infrastructure Regulation(AFIR), Re Fuel EU and Fue... April 18, Brussels, Belgium In light of recent significant regulatory changes within the European Union impacting the transport sector, such as the Alternative Fuels Infrastructure Regulation(AFIR), Re Fuel EU and Fuel EU Maritime, the role of European standardization becomes increasingly critical in facilitating the transition towards the deployment of alternative fuels. 展开更多
关键词 TRANSITION alternative MARITIME
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Use of Topical Complementary and Alternative Medicines (CAM) in Diabetic Septic Foot Disease in Makkah Region, Western of Saudi Arabia, an Exploratory Study
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作者 Mohamed Elamin Salih Hatim Alrizqi +5 位作者 Mohammed Hussain Abdullah Alshumrani Ismail Alhasani Ali Alkhamisi Hamzah Alsayed Fahad Alqarni 《Journal of Biosciences and Medicines》 2024年第3期245-258,共14页
Diabetes is a chronic condition that is significantly impacted daily by environment. At least one in five Saudis, suffer from diabetes. “Diabetes is a pandemic of unprecedented magnitude spiraling out of control” (B... Diabetes is a chronic condition that is significantly impacted daily by environment. At least one in five Saudis, suffer from diabetes. “Diabetes is a pandemic of unprecedented magnitude spiraling out of control” (Boulton). Saudi Arabia ranks the second highest in the Middle East, and is the seventh in the world for the prevalence of diabetes (WHO). Diabetes mellitus (DM) has been found to be related to high mortality, morbidity accompanied by poor general health and lower quality of life. Current Saudi diabetes patients’ behaviors, practices, and beliefs regarding foot health problems such as ulcers, are not well investigated. Diabetic patients frequently utilize natural remedies and Herbs for self-medication as a part of complementary and alternative Medicine. Aim of study: To explore the widespread use of the alternative remedies in the local communities of the Western Saudi Arabia, the drives behind using and to focus on the potential adverse effects following their usage. Method: A descriptive, cross-sectional study of 386 diabetic patients with feet problems in Makkah Region, West of Saudi Arabia during the period April - June 2023. Results: Out of the 531 participants, only 386 participants reported diabetic foot disorder (DFD). Most of the participant were above 65 years of age group (24.61 %). Male (52.08%) more than female (47.92%) in the research group. All of the participants had diabetic foot disorders at least once. The prevalence of complementary and alternative medicines (CAM) use among them was 67.88%, as solitary or in combination with hospital medicines. Honey headed the list followed by myrrh and black seeds. Acquaintances advice (59.54%) was the most reason for using the alternative medicine. 60.30% of Diabetic foot patient complained of adverse effects during CAM remedies use. Conclusion: Consumption of CAM remedies among diabetic patients for Diabetic Foot Disorder (DFD) is common. Honey headed the list followed by myrrh and black seeds. Additional wide-scale research is required to establish their actual efficacy, safety and potential adverse out-comes and to generalize the outcomes. 展开更多
关键词 Diabetic Foot Ulcer Diabetes Complementary and alternative Medicine CAM West of Saudi Arabia
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Molecular targets and mechanisms of different aberrant alternative splicing in metastatic liver cancer
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作者 De-Yi Geng Qing-Shan Chen +7 位作者 Wan-Xian Chen Lin-Sa Zhou Xiao-Sha Han Qi-Hu Xie Geng-Hong Guo Xue-Fen Chen Jia-Sheng Chen Xiao-Ping Zhong 《World Journal of Clinical Oncology》 2024年第4期531-539,共9页
Metastasis remains a major challenge in the successful management of malignant diseases.The liver is a major site of metastatic disease and a leading cause of death from gastrointestinal malignancies such as colon,sto... Metastasis remains a major challenge in the successful management of malignant diseases.The liver is a major site of metastatic disease and a leading cause of death from gastrointestinal malignancies such as colon,stomach,and pancreatic cancers,as well as melanoma,breast cancer,and sarcoma.As an important factor that influences the development of metastatic liver cancer,alternative splicing drives the diversity of RNA transcripts and protein subtypes,which may provide potential to broaden the target space.In particular,the dysfunction of splicing factors and abnormal expression of splicing variants are associated with the occurrence,progression,aggressiveness,and drug resistance of cancers caused by the selective splicing of specific genes.This review is the first to provide a detailed summary of the normal splicing process and alterations that occur during metastatic liver cancer.It will cover the role of alternative splicing in the mechanisms of metastatic liver cancer by examining splicing factor changes,abnormal splicing,and the contribution of hypoxia to these changes during metastasis. 展开更多
关键词 alternative splicing CARCINOMA HEPATOCELLULAR Metastasic Liver neoplasms PROGNOSIS
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Progression of Corneal Astigmatism after Phaco-Alternative at the University Hospital Center of the Oueme-Plateau Department in Porto-Novo
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作者 Chakiratou Olaïdé Adoukê Abouki Edjrokinto Ahomadegbe Djrodéhou Espérancia Neuilly +4 位作者 Issifou Amadou Alfa Bio Nestor Aïgbè Soulé Alamou Lisette Odoulami Ignace Sounouvou 《Open Journal of Ophthalmology》 2024年第3期313-323,共11页
Objective: To study the postoperative evolution of corneal astigmatism following phaco-alternative at the University Hospital Center of Ouémé-Plateau (UHC-OP) in Porto-Novo. Method: This was a prospective, c... Objective: To study the postoperative evolution of corneal astigmatism following phaco-alternative at the University Hospital Center of Ouémé-Plateau (UHC-OP) in Porto-Novo. Method: This was a prospective, cross-sectional study with a descriptive and analytical purpose conducted from April 19 to September 20, 2021;a period of 6 months. The study included all patients presenting with senile or non-senile cataracts without a history of corneal trauma and who underwent phaco-alternative during the study period. Results: A total of 62 eyes underwent phaco-alternative. The average age was 63 ± 12 years with a male predominance of 59.7%. Phaco-alternative was performed with 74.2% linear incision and 25.8% smile incision. Perioperative incidents were mainly capsular ruptures with vitreous loss occurring in 8.1% of cases. The mean preoperative astigmatism was 1.29 ± 1.5 D with an axis of 180˚ ± 20˚, indicating with-the-rule astigmatism. The mean postoperative astigmatism was 2.2 ± 1.5 D with an axis of 90˚ ± 20˚, indicating against-the-rule astigmatism. The mean induced astigmatism at Day 30 was 1.4 ± 1.2 D for smile incision and 1.8 ± 1.2 D for linear incision. Conclusion: Phaco-alternative yields good results with few complications but remains astigmatogenic. The smile incision appears to be less astigmatogenic. 展开更多
关键词 Cataract Phaco-alternative Smile Incision ASTIGMATISM
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中医药治疗特发性少弱精子症的思路与方法 被引量:3
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作者 张芳 孙自学 +2 位作者 陈建设 门波 李鹏超 《辽宁中医杂志》 CAS 北大核心 2024年第1期38-42,共5页
特发性少弱精子症是男性不育症的常见原因,具有病程长、病因不明、发病率高的特点。随着育龄、高龄夫妇生育需求的增加本病呈现渐增趋势,影响家庭美满、社会和谐。近年来中医医家对特发性少弱精子症的研究日益深入,立足学术典籍,结合自... 特发性少弱精子症是男性不育症的常见原因,具有病程长、病因不明、发病率高的特点。随着育龄、高龄夫妇生育需求的增加本病呈现渐增趋势,影响家庭美满、社会和谐。近年来中医医家对特发性少弱精子症的研究日益深入,立足学术典籍,结合自身经验提出对本病的认识,形成了丰富多样的诊疗思路与方法。特发性少弱精子症病位主要在肾,本虚标实是其基本病机特点。治疗上除口服中药改善患者临床症状,提高精子质量外,针刺、艾灸等中医传统疗法也广泛应用于临床,中、西医融合疗法更是弥补了各自的不足,但同时也存在着一些问题。现从中医病机、名医经验、治疗研究等方面,总结目前中医药治疗特发性少弱精子症的状况,并针对不足提出合理化建议,以期推动中医药在本病治疗中的发展和应用。 展开更多
关键词 特发性少精子症 中医药 思路与方法
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弱监督场景下的支持向量机算法综述 被引量:2
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作者 丁世飞 孙玉婷 +3 位作者 梁志贞 郭丽丽 张健 徐晓 《计算机学报》 EI CAS CSCD 北大核心 2024年第5期987-1009,共23页
支持向量机(Support Vector Machine,SVM)是一种建立在结构风险最小化原则上的统计学习方法,以其在非线性、小样本以及高维问题中的独特优势被广泛应用于图像识别、故障诊断以及文本分类等领域.但SVM是一种监督学习算法,它旨在利用大量... 支持向量机(Support Vector Machine,SVM)是一种建立在结构风险最小化原则上的统计学习方法,以其在非线性、小样本以及高维问题中的独特优势被广泛应用于图像识别、故障诊断以及文本分类等领域.但SVM是一种监督学习算法,它旨在利用大量的、唯一且明确的真值标记样本来训练学习器,在不完全监督、不确切监督以及多义监督等弱监督场景下难以取得较好的效果.本文首先阐述了弱监督场景的概念和SVM的相关理论,然后从弱监督场景角度出发,系统地梳理了目前SVM算法的研究现状和发展,包括基于半监督学习、多示例学习以及多标记学习的方法;其中基于半监督学习的方法根据数据假设可细分为基于聚类假设和基于流形假设的方法,基于多标记学习的方法根据解决方案可细分为基于示例水平空间、基于包水平空间以及基于嵌入空间的方法,基于多标记学习的方法根据处理思路可细分为基于问题转换和基于算法自适应的方法;随后,本文总结了部分代表性算法在公开数据集上的实验结果;最后,探讨并展望了未来可能的研究方向. 展开更多
关键词 监督场景 支持向量机 半监督学习 多示例学习 多标记学习
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弱电网下基于电网电压前馈的并网逆变器阻抗重塑控制策略 被引量:2
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作者 杨明 杨倬 +1 位作者 李玉龙 朱军 《电工技术学报》 EI CSCD 北大核心 2024年第8期2553-2566,共14页
弱电网下,锁相环在基波以上频段引入的负阻特性,会降低系统输出阻抗的相位,严重影响系统稳定性。鉴于此,该文通过系统控制框图等效变换,推导得到可以消除锁相环负阻特性的电网电压前馈函数,进而提出一种基于电网电压前馈控制的并网逆变... 弱电网下,锁相环在基波以上频段引入的负阻特性,会降低系统输出阻抗的相位,严重影响系统稳定性。鉴于此,该文通过系统控制框图等效变换,推导得到可以消除锁相环负阻特性的电网电压前馈函数,进而提出一种基于电网电压前馈控制的并网逆变器阻抗重塑控制策略。同时,为了提高该策略的普适性,该文利用函数近似和多目标约束为电网电压前馈函数的优化提供两种设计方法,并从系统基波电流跟踪性能、并网功率因数等方面进行误差分析,从而证明其函数优化设计方法的可行性。理论分析表明,优化后的电网电压前馈控制策略,可以有效地对系统输出阻抗相位特性进行重塑,很大程度上拓宽了系统对电网阻抗的适应范围。最后,通过仿真与实验验证所提控制策略的有效性。 展开更多
关键词 电网 并网逆变器 阻抗重塑 锁相环 稳定性
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弱酸性电解水用于提升鲜切马铃薯安全品质的研究 被引量:2
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作者 李玉梅 程建新 +4 位作者 葛霞 田世龙 李守强 田甲春 李梅 《食品安全质量检测学报》 CAS 2024年第1期197-205,共9页
目的探究弱酸性电解水和自来水处理的鲜切马铃薯在室温贮藏条件下不同时间段内品质的变化。方法模拟现代厨房贮存模式,经弱酸性电解水和自来水处理的鲜切马铃薯在室温(25±0.5)℃贮藏环境下,贮藏0、7、14、21、28、35h时,检测其感... 目的探究弱酸性电解水和自来水处理的鲜切马铃薯在室温贮藏条件下不同时间段内品质的变化。方法模拟现代厨房贮存模式,经弱酸性电解水和自来水处理的鲜切马铃薯在室温(25±0.5)℃贮藏环境下,贮藏0、7、14、21、28、35h时,检测其感官、色度、质构、淀粉、蛋白质、钾、维生素C、菌落总数、大肠杆菌、沙门氏菌、金黄色葡萄球菌、霉菌、酵母菌。结果经弱酸性电解水处理的鲜切马铃薯在室温贮藏21 h内,经自来水处理的鲜切马铃薯在室温贮藏14 h内,感官正常,其营养成分淀粉、蛋白质、维生素C、钾元素下降较少,金黄色葡萄球菌、沙门氏菌、菌落总数、大肠杆菌、霉菌、酵母菌的含量均在国家标准和团体标准许可的安全范围内,可安全食用。结论弱酸性电解水可显著提升鲜切马铃薯的贮藏品质,抑制其金黄色葡萄球菌、沙门氏菌、菌落总数、大肠杆菌、霉菌、酵母菌繁殖,延长室温贮藏期。 展开更多
关键词 酸性电解水 鲜切马铃薯 安全品质 微生物 营养成分 质构特性
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弱电网下光伏并网系统锁相环参数自适应控制 被引量:1
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作者 武海涛 张宁宁 +3 位作者 曹志轩 温素芳 李磊 李会珍 《电网与清洁能源》 CSCD 北大核心 2024年第1期52-61,共10页
针对弱电网下PLL(phase-looked loop,PLL)会使并网逆变器的稳定性下降问题,提出一种锁相环带宽自适应控制策略来实现锁相环参数依据电网实时阻抗值来获得最优的控制参数,保证系统最佳控制性能和稳定运行,从而提升跟网型逆变器在弱电网... 针对弱电网下PLL(phase-looked loop,PLL)会使并网逆变器的稳定性下降问题,提出一种锁相环带宽自适应控制策略来实现锁相环参数依据电网实时阻抗值来获得最优的控制参数,保证系统最佳控制性能和稳定运行,从而提升跟网型逆变器在弱电网下的对电网阻抗的适应能力。利用PSCAD/EMTDC进行仿真验证,仿真结果证明自适应控制策略正确、有效。 展开更多
关键词 电网 锁相环 谐波线性化 稳定边界 参数自适应
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可实现弱等效方案排序的改进TOPSIS排序法
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作者 程幼明 胡祥瑛 +1 位作者 何惠妍 吴锋 《运筹与管理》 CSSCI CSCD 北大核心 2024年第8期128-134,共7页
针对TOPSIS法可能存在多个备选方案的接近度相同而无法进行全排序的问题。首先,考虑到等效方案在正、负理想解距离上的差异,本文将其细分为强等效方案(不同方案到理想解距离相等)与弱等效方案(不同方案到理想解距离的比值相等但距离不等... 针对TOPSIS法可能存在多个备选方案的接近度相同而无法进行全排序的问题。首先,考虑到等效方案在正、负理想解距离上的差异,本文将其细分为强等效方案(不同方案到理想解距离相等)与弱等效方案(不同方案到理想解距离的比值相等但距离不等)。其次,以二维目标为坐标系描述TOPSIS系统,发现TOPSIS评价系统中有:(1)所有方案均位于某一特定区域;(2)强等效方案为同一点,而弱等效方案则位于特定直线上等特性。进而,依据二维目标空间下等效方案与正、负理想解的相对位置关系,针对存在弱等效方案的TOPSIS评价系统,提出一种在依据接近度对备选方案进行分组与组间排序基础上,重新定义排序指数对组内等效方案实施排序。从而设计出一种组间排序基础上的组内排序与组间排序相结合的改进TOPSIS排序法。该方法既不改变方案的原有TOPSIS排序,又可实现弱等效方案的全排序。最后通过数值分析验证所提出方法的合理性和有效性。 展开更多
关键词 TOPSIS 排序方法 等效方案 接近度
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底板动压巷道压裂弱结构体应力转移控制技术 被引量:2
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作者 陈绍杰 刘江伟 +1 位作者 李亚康 吕华 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第1期106-116,共11页
为了满足煤矿安全生产的需要,许多巷道都会布置在煤层底板中,如部分运输大巷、排水巷道、瓦斯抽采巷道等。采动应力容易造成底板巷道围岩应力升高,加剧底板巷道围岩变形,造成支护永久失效、顶板下沉、巷道底鼓、两帮收敛等破坏。针对此... 为了满足煤矿安全生产的需要,许多巷道都会布置在煤层底板中,如部分运输大巷、排水巷道、瓦斯抽采巷道等。采动应力容易造成底板巷道围岩应力升高,加剧底板巷道围岩变形,造成支护永久失效、顶板下沉、巷道底鼓、两帮收敛等破坏。针对此,提出了在应力传递路径上实施水力压裂,在指定的区域制造出一定空间形态的水压裂缝网,形成压裂弱结构体,实现区域范围内的应力转移,从而降低巷道区域范围内的应力,控制巷道的围岩稳定性的控制技术,并通过理论分析及现场工程验证等方式,揭示了底板动压巷道压裂弱结构体应力转移的力学机制,建立了相应的力学模型,对压裂弱结构体的合理位置、范围等影响因素进行了求解。得出:(1)压裂弱结构体使局部应力场发生明显变化,出现应力升高区和应力降低区,应力降低区主要分布在弱结构体与采动应力连线的方向上,主要集中在一个拱形的范围内;由于膨胀效应,在与应力来源垂直的方向上产生应力集中,出现应力升高区。(2)最大主应力变化幅度与压裂弱结构体的长轴长L、短轴长H、到巷道的距离P、与巷道连线的水平夹角β、压裂层的强度C及内摩擦角α、压裂的损伤变量D等有关。其中到巷道的距离P对卸压效果影响最大,损伤变量D对卸压效果影响最小。(3)采用提出的计算方法设计了淮北矿业集团袁店一矿的103运输集中巷的卸压方案,工程应用结果表明,底板动压巷道变形速率明显减缓,验证了底板强动压巷道压裂弱结构体应力转移模型的合理性。 展开更多
关键词 采动应力 结构体 水力压裂 卸压 切顶 围岩控制
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弱共识与语境复义:人工智能自然语言大模型重塑文艺美学 被引量:1
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作者 刘方喜 《社会科学辑刊》 CSSCI 北大核心 2024年第1期201-208,共8页
实质语义的弱共识性是人工智能自然语言大模型自动生成文本的基本特性,也是文学文本的基本特性。科学与文学文本语元组合运动生成的形式语义都要在个人的直观理解中转化为实质语义。形式语义概念化的单义决定着科学文本实质语义的强共识... 实质语义的弱共识性是人工智能自然语言大模型自动生成文本的基本特性,也是文学文本的基本特性。科学与文学文本语元组合运动生成的形式语义都要在个人的直观理解中转化为实质语义。形式语义概念化的单义决定着科学文本实质语义的强共识,有利于汇聚物化在语言符号中的社会力量,以认识、改造自然物元组合运动而造福人类;形式语义实例性的语境复义决定着文学文本实质语义的弱共识,有助于个人心元组合运动的和谐化、文明化和个人性与社会性相统一的非强制性交往。大模型颠覆了传统科学文化概念化强共识公理系统,对于重新认识科学文化与人文文化两者之间的关系及价值、重塑传统文艺美学和人类文化等有重要启示。 展开更多
关键词 共识 语境复义 实质语义 形式语义 自然语言大模型
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偏序集上的弱Scott拓扑与弱测度拓扑
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作者 王武 李旭东 《四川师范大学学报(自然科学版)》 CAS 2024年第2期264-268,共5页
讨论偏序集的s_(2)连续性和弱Scott拓扑的一些性质:给出s_(2)连续偏序集上伴随的一些性质;定义弱测度拓扑,研究s_(2)连续偏序集上弱测度拓扑的性质;利用弱测度拓扑给出s_(2)交连续偏序集的等价刻画;研究弱Scott拓扑的连通性.
关键词 偏序集 s_(2)连续 伴随 Scott拓扑 测度拓扑 连通性
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优质弱筋小麦新品种宁麦36的选育研究
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作者 姚金保 杨学明 +4 位作者 张鹏 余桂红 何漪 王化敦 范祥云 《安徽农业科学》 CAS 2024年第11期16-18,共3页
宁麦36(参试品种名宁麦7342)由江苏省农业科学院粮食作物研究所以扬麦20为母本,宁麦14为父本配制杂交,后代采用改良集团选择法育成的小麦新品种。该品种在2019—2022年江苏省农业科学院科企淮南小麦联合体区域试验和生产试验中,平均产... 宁麦36(参试品种名宁麦7342)由江苏省农业科学院粮食作物研究所以扬麦20为母本,宁麦14为父本配制杂交,后代采用改良集团选择法育成的小麦新品种。该品种在2019—2022年江苏省农业科学院科企淮南小麦联合体区域试验和生产试验中,平均产量比对照扬麦20分别增产4.81%和5.99%。宁麦36有效穗数538.5万/hm^(2),穗粒数40.8粒,千粒重42.2 g。中抗赤霉病,弱筋。相关分析表明,有效穗数与产量呈极显著正相关;通径分析表明,有效穗数对产量的贡献最大,穗粒数次之,千粒重较小。宁麦36的高产栽培技术应是主攻穗数,兼顾增加穗粒数和千粒重。 展开更多
关键词 筋小麦 产量 栽培技术 宁麦36
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弱透水层瞬态水力参数的地质统计反演识别研究
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作者 庄超 余文平 +5 位作者 严龙 张健翼 窦智 杨蕴 周志芳 王锦国 《地质学报》 EI CAS CSCD 北大核心 2024年第1期324-331,共8页
弱透水层释水变形伴随着水力参数(渗透系数K和贮水率Ss)的瞬态变化,传统的“移动窗口”式反演方法假定每个反演窗口的初始状态是静态的,这与弱透水层释水变形存在明显滞后效应的实际情况不符。本文提出了在高维参数反演优化情境下,时间... 弱透水层释水变形伴随着水力参数(渗透系数K和贮水率Ss)的瞬态变化,传统的“移动窗口”式反演方法假定每个反演窗口的初始状态是静态的,这与弱透水层释水变形存在明显滞后效应的实际情况不符。本文提出了在高维参数反演优化情境下,时间域上模型参数的动态变化可与空间域上模型参数的一维非均质性等价,因而可用地质统计反演方法可用于识别弱透水层瞬态K和Ss的新思路,实现了该方法在水文地质领域的创新性应用。以上海越流含水层系统为例,运用似线性地质统计反演算法,高精度地拟合了F16分层标处的长观变形数据,获取了原位透镜体状弱透水层K和Ss的瞬态特征。反演结果显示,观测时段内K的变幅为1.02×10^(-5)~5.89×10^(-4)m/a,平均值为1.38×10^(-4)m/a,Ss的变幅为4.34×10^(-4)~6.02×10^(-3)m^(-1),平均值为2.65×10^(-3)m^(-1)。基于反演所得参数瞬态特征,分析原位弱透水层在1994年前后分别以弹性和塑性变形为主,弱透水层K呈现与含水层水位相反的季节性变化特征,该现象可能与渗流力作用下细粒物质在含水层与弱透水层透镜体交界面附近的对孔隙的阻塞和疏通作用有关。该方法可获取完整观测时段内水文地质参数的动态变化轨迹,在计算评价地表水-地下水交互领域的河床渗透性、原位修复领域的渗透反应墙渗透性等的动态演化特征方面具有潜在的应用价值,并可作为构建水文地质领域、岩土工程等领域有关本构模型的有效辅助手段。 展开更多
关键词 透水层 瞬态水力参数 地质统计反演 时空等价性
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