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Investigating Storage Mode and Shelf Life of Bagged TCM Decoctions under Different Conditions
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作者 Hongbin SHI Yongdong XU +7 位作者 Qiujing LU Xiaoli HE Cai LI Xiaoting ZHU Danping LI Fengjing YAN Shujiao HOU Jianlian CHEN 《Medicinal Plant》 2025年第2期28-31,共4页
[Objectives]To investigate optimal storage methods and shelf life determination for several representative bagged traditional Chinese medicine(TCM)decoctions under centralized preparation conditions in intelligent TCM... [Objectives]To investigate optimal storage methods and shelf life determination for several representative bagged traditional Chinese medicine(TCM)decoctions under centralized preparation conditions in intelligent TCM pharmacies.[Methods]First,the nourishing formula was prepared and packaged in bags.Under the three storage conditions of 37℃before cold storage(including full high temperature),cold storage before 37℃(including full cold storage),and alternating 37℃and cold storage,the 30 d cycle was investigated to determine the total microbial colony count,so as to determine a reasonable storage method of traditional Chinese medicine decoction.Secondly,five representative prescriptions were prepared and packaged in bags,stored under 37℃,room temperature and cold conditions.The investigation period was 30 d.The pH,total bacterial count and soluble solid content were measured,and the changes of each index were analyzed to obtain the shelf life of the bagged Chinese medicine decoction.[Results]First,the nourishing formula was investigated for 30 d.The microbial results of refrigeration after 1-2 d of 37℃,complete refrigeration and 37℃cooling with an alternate interval of 2 d or less met the requirements,while the microbial results of refrigeration after 3 d or above of 37℃,refrigeration after 1-5 d and then 37℃,complete 37℃,37℃and cooling with an alternate interval of 3 d or above excessive microorganism.Second,under the condition of 37℃storage,the pH of the five prescriptions decreased significantly,the total microbial colonies exceeded the standard,and the solid content decreased significantly.However,under the condition of room temperature and cold storage,the pH,total microbial colonies,and solid content of the five prescriptions remained stable.[Conclusions]The first is to refrigerate the decoction after 1-2 d of 37℃,completely refrigerate it,and refrigerate the decoction with an alternate interval of 2 d or less at 37℃.The shelf life can last for 30 d.Several storage conditions are conducive to guiding the development of the storage mode of the decoction.Second,under the conditions of cold storage,all the indexes were stable,and the shelf life of the five representative formulas was 30 d. 展开更多
关键词 bagged TCM decoctions Shelf-life determination Total microorganism PH Solid content
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Effect of Metaxenia on Volatile Compounds in Bagged Apple Fruit of Fuji 被引量:8
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作者 王海波 王传增 +3 位作者 程来亮 常源升 何平 李林光 《Agricultural Science & Technology》 CAS 2017年第4期583-587,610,共6页
In the present study, the effect of pollen grain sources on volatile com- pounds in bagged apple fruit of Yan Fuji 3, grown at two experiment sites and pol- linated by pollens of other five cultivars was evaluated, to... In the present study, the effect of pollen grain sources on volatile com- pounds in bagged apple fruit of Yan Fuji 3, grown at two experiment sites and pol- linated by pollens of other five cultivars was evaluated, to select appropriate poll- enizer cultivars for Fuji, and to provide a theoretical basis for improving the flavor and aroma of bagged apple fruit of Fuji. The results proved the significant metaxe- nia effect of the five pollenizer cultivars on volatile compounds of bagged apple fruit of Fuji. The numbers of both volatile compounds and characteristic aroma com- pounds in bagged apple fruit pollinated by Golden Delicious were larger and those of the fruit pollinated by Gala were smaller at both experiment sites. However, there were differences in the numbers of volatile compounds and characteristic aroma compounds among the fruits pollinated by Starkrimson, Jinxiuhaitang and Ruby at both experimental sites. The differences were caused by 12 compounds that only existed at a low level in certain samples. All of them were not the aroma contribu- tors except ethyl 2-methylbutyrate. The content of alcohols in bagged Fuji fruit was largely increased by Starkrimson and Ruby pollination; the content of aldehydes was obviously increased by Golden Delicious, Starkrimson and Gala pollination; the con- tents of esters and terpenes were significantly increased by Golden Delicious, Starkrimson and Ruby pollination. Jinxiuhaitang pollination showed no significant ef- fects for improving the content of four categories of volatile compounds. The metax- enia of the pollenizer cultivars on volatile compounds in bagged Fuji fruit was stable at the two experimental sites. 展开更多
关键词 Metaxenia Fuji apple bagged fruits Volatile compounds
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Effect of Metaxenia on Sugars and Organic Acids and Taste Quality of Bagged Fuji Apple Fruits 被引量:2
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作者 Haibo WANG Chuanzeng WANG +3 位作者 Lailiang CHENG Yuansheng CHANG Ping HE Linguang LI 《Agricultural Biotechnology》 CAS 2017年第4期63-66,共4页
In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars,... In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars, organic acids and flavor quality of bagged Fuji fruit were studied. The results showed that the 5 pollination varieties had significant metaxenia effects on sugars, organic acids and flavor quality of bagged Fuji fruit. For the sugar components, the fruits pollinated with Golden Delicious and Jinxiuhaitang showed higher glucose contents, and the fruit pollinated with Gala had the highest sucrose content; the fruits pollinated by Gala, Golden Delicious and Ruby exhibited higher malic acids, and the oxalic acid content and the succinic acid content were higher in the fruits pollinated with Jinxiuhaitang and Ruby ; and the fruit pollinated with Gala had the highest total sugar content, and the total acid content was higher in the fruits pollinated by Jinxiuhaitang and Ruby. The sugar-acid ratio was higher in the fruits pollinated with Gala and Golden Delicious, and the lowest in the fruit pollinated with Ruby. The senso- ry evaluation of fruits showed that the fruit pollinated with Ruby tasted sour-sweet, while the fruits pollinated with other 4 pollination varieties were sour and sweet moderately. 展开更多
关键词 Metaxenia Fuji apple bagged fruits Sugars and organic acids flavor quality
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The result of bagged Pyrinuron baits for controlrodent pest of forests
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作者 马力 邓刚 张蕊 《Journal of Forestry Research》 CAS CSCD 2000年第1期72-73,共2页
Bagged and dispersed Pyrinuron (a self-formulated rodenticide) were tested for control of Clethrionomus rutilus and Clethrionomus rufocanus in larch plantation, Pingshan area, Heilongjiang Province from Oct. 1998 to A... Bagged and dispersed Pyrinuron (a self-formulated rodenticide) were tested for control of Clethrionomus rutilus and Clethrionomus rufocanus in larch plantation, Pingshan area, Heilongjiang Province from Oct. 1998 to Apr. 1999. The results showed that the bagged Pyrinuron has good result for control of the two rodent pests. The density of rodents was reduced by 90.5% after application of bagged Pyrinuron. This application method has characteristics of long residual period, bait not going mould and saving labour force. 展开更多
关键词 bagged RODENTICIDE Pyrinuron LARCH PLANTATION RODENT pest CONTROL
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基于Bagged CART和Boosted CART的高光谱影像分类技术研究
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作者 徐卫霄 余旭初 王善秀 《影像技术》 CAS 2011年第5期14-17,共4页
本文针对高光谱影像数据光谱分辨率高,数据量大的特点,采用以CART决策树为弱分类器的Bagging和Boosting集成学习算法对该影像进行分类,通过实验分析比较,体现出了Bagged CART和Boosted CART算法用于分类时的有效性和准确性。
关键词 高光谱 CART BAGGING BOOSTING
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基于可解释性因子选择的多模型耦合式大坝变形预测方法
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作者 柳聪聪 张锋 +2 位作者 胡超 张启灵 郭永成 《长江科学院院报》 北大核心 2026年第1期144-154,共11页
目前,传统、单一模型难以全面捕捉大坝变形数据的复杂性和多样性,导致其预测性能和解释能力受限。为解决上述问题,通过对多种预测模型的组合与优化,提出了一种高效且具备可解释性的大坝变形预测方法。首先,利用最小绝对值收缩和选择算子... 目前,传统、单一模型难以全面捕捉大坝变形数据的复杂性和多样性,导致其预测性能和解释能力受限。为解决上述问题,通过对多种预测模型的组合与优化,提出了一种高效且具备可解释性的大坝变形预测方法。首先,利用最小绝对值收缩和选择算子(LASSO)在众多环境变量中高效筛选,既简化模型输入,又解释了因子选择的可靠性。然后,采用长短期记忆(LSTM)网络对大坝变形进行预测,并引入注意力机制,增强对重要信息的提取。最后,通过Bagging算法集成多个模型预测结果,进一步提高整体预测的准确度、稳定性和泛化能力。以某碾压混凝土重力坝为例,所构建的模型具有较高的预测精度,各测点上平均MAE、MSE、RMSE依次为0.052、0.005、0.067 mm。将耦合模型与多种常用模型对比分析,结果表明耦合模型能够更准确地捕捉到大坝变形的动态变化,为预测模型研究提供了一种简洁高效的方法。 展开更多
关键词 大坝变形预测 最小绝对值收缩和选择算子(LASSO) 注意力机制 长短期记忆(LSTM) BAGGING算法 耦合模型
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Transcriptome and metabolome analysis reveals regulatory network associated with light-independent anthocyanin biosynthesis in blueberry fruit
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作者 Xuyan Li Shouwen Wang +7 位作者 Hongxue Li Fangyun Qian Haiyang Wang Jingying Wang Lulu Zhai Baosheng Shi Junwei Huo Shaomin Bian 《Horticultural Plant Journal》 2026年第3期584-602,共19页
Anthocyanins are vital secondary metabolites contributing to fruit pigmentation and antioxidative properties.While light is a well-known regulator of anthocyanin biosynthesis,the molecular basis of light-independent a... Anthocyanins are vital secondary metabolites contributing to fruit pigmentation and antioxidative properties.While light is a well-known regulator of anthocyanin biosynthesis,the molecular basis of light-independent anthocyanin accumulation remains underexplored.In this study,integrated analysis of metabolome and transcriptome showed that the anthocyanin content in blueberry(Vaccinium corymbosum‘Bluetta’)fruit was slightly decreased by light-impermeable bagging treatment,while anthocyanin biosynthetic genes were transcriptionally inhibited to different levels,suggesting a slight influence of the bagging treatment on anthocyanin accumulation.Further observation showed that fruit bagging did not alter ethylene production but decreased ABA content.Noticeably,two VcMYBA/MYB1s were not transcriptionally altered by the light-impermeable bagging treatment.Consistently,histochemical GUS analysis and pharmacological manipulation suggested light-independent and ethylene-inducible expression of VcMYBA/MYB1.Moreover,WGCNA analysis revealed 3759 genes positively associated with MYBA/MYB1 such as ethylene-associated genes,etc.Additionally,VcbZIP55s and VcCOP1s were activated and inactivated by the bagging treatment,respectively.These findings provided a framework of light-independent anthocyanin biosynthesis in blueberry fruit. 展开更多
关键词 Vaccinium corymbosum BAGGING Light-independent regulation TRANSCRIPTOME METABOLOME Anthocyanins MYBA Ethylene signaling
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Integrated transcriptome and metabolome analysis reveals light induction of anthocyanin rapid accumulation in red-fleshed peach after pre-harvest bagging
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作者 Jia Wei Fengjie He +6 位作者 Kexin Sun Li Wang Yiming Yin Junbei Ni Songling Bai Yuanwen Teng Huijuan Jia 《Horticultural Plant Journal》 2026年第3期539-554,共16页
Red-fleshed fruits are valued for their vibrant color and high anthocyanin content.Pre-harvest fruit bagging enhances fruit peel pigmentation,but its effect on flesh coloration remains poorly characterized.This study ... Red-fleshed fruits are valued for their vibrant color and high anthocyanin content.Pre-harvest fruit bagging enhances fruit peel pigmentation,but its effect on flesh coloration remains poorly characterized.This study revealed that removing bags from‘Gengcunyangtao’red-fleshed peach fruits triggers the rapid and uniform accumulation of anthocyanins in the flesh,resulting in anthocyanin levels that exceed those in unbagged fruits.The exposure to light after bag removal triggered significant increases in anthocyanin levels within 24 h.This was accompanied by the rapid upregulation of light-responsive and flavonoid biosynthetic gene expression levels within 6 h.A metabolomic analysis indicated that anthocyanin precursors,especially p-coumaric acid,accumulated before bag removal,thereby increasing substrate availability for rapid anthocyanin synthesis.On the basis of a weighted gene co-expression network analysis,MYB transcription factors,anthocyanin transporters,glutathione S-transferase,and multidrug and toxic compound extrusion(MATE)were identified as key regulators that coordinate precursor storage along with light-induced transcriptional activation.Notably,PpMYB4 binds to the promoter of PpGSTF14 and activates its expression,thereby promoting anthocyanin accumulation.The study findings elucidated the temporal coordination of metabolic priming and light-responsive transcriptional regulation driving rapid anthocyanin biosynthesis,with possible implications for improving peach fruit flesh coloration. 展开更多
关键词 Red-fleshed peach ANTHOCYANIN Pre-harvest fruit bagging Light exposure Transcriptome analysis Metabolome analysis
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Tree community composition modulates early-stage decomposition of standard litter through chemical and physical engineering
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作者 Joachim López Karen Vancampenhout +1 位作者 Bart Muys Quentin Ponette 《Forest Ecosystems》 2026年第1期22-34,共13页
Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and ... Litter decomposition is an essential ecosystem process influenced by multiple factors,including substrate quality,climate,edaphic environment,and decomposer communities.However,the role of canopy species identity and diversity on leaf litter decomposition in forests remains understudied.By controlling for macroclimate,soil properties,and litter substrate in a mature common garden,we investigated whether a three-month tea bag incubation of standardized green and rooibos tea substrate is driven by canopy tree species characteristics and diversity.Our study hypothesized two primary pathways:a chemical engineering effect,where trees alter soil properties and decomposer communities through litter input,and a physical engineering effect,where tree canopy structure modulates the local microclimate.The results showed that even under uniform macroclimatic and initial soil conditions,mass loss rates varied widely for green tea(27.4%–73.2%)and rooibos tea(6.1%–34.7%),comparable as found in other research between distinct biomes.While substrate quality was the dominant factor,both engineering pathways and,to a minor extent,tree diversity modulated mass losses.For green tea,tree chemical and physical characteristics seemed equally important,while the physical environment showed an increased importance for rooibos.Incubation depth played a key role,where forest floor decomposition rates are more susceptible to temporal climate variations,and soil-layer decomposition rates are less susceptible to climate variations and more determined by tree species identity.Our findings suggest that tea bag experiments focusing solely on topsoil burial may underestimate processes in the forest floor and the mineralorganic boundary layer.This study underscores the critical role of litter substrate quality in decomposition while demonstrating that tree community composition and the associated herbaceous layer,through both chemical and physical engineering pathways,strongly modulate decomposition rates. 展开更多
关键词 Tea bag incubation Early-stage litter decomposition Geographical arboretum Tree species composition
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基于Bagging集成学习的引水及城乡供水工程投资概算模型
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作者 苏明明 《黑龙江水利科技》 2026年第2期188-191,共4页
为提高工程投资概算结果的准确性,基于Bagging集成学习技术的应用,以引水及城乡供水工程为例,开展工程投资概算模型的构建研究。采集工程投资主要指标数据,结合工程需求,进行数据处理;利用完成处理后的工程投资主要指标数据,对投资概算... 为提高工程投资概算结果的准确性,基于Bagging集成学习技术的应用,以引水及城乡供水工程为例,开展工程投资概算模型的构建研究。采集工程投资主要指标数据,结合工程需求,进行数据处理;利用完成处理后的工程投资主要指标数据,对投资概算模型超参数进行优化设计;引进Bagging集成学习算法,进行投资概算模型偏差处理设计,实现引水及城乡供水工程投资概算模型的构建。对比实验结果表明,设计的方法不仅可以实现对工程投资的精准概算,还能有效减少模型在训练中的损失度,保证投资概算结果的可靠性。 展开更多
关键词 Bagging集成学习 超参数优化 数据处理 投资概算模型 城乡供水工程 引水
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BAG3 in traumatic brain injury:A cell-type-specific modulator of tau hyperphosphorylation
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作者 Nicholas Sweeney Tae Yeon Kim Hongjun Fu 《Neural Regeneration Research》 2026年第6期2343-2344,共2页
BCL2-associated anthanogene 3 facilitates the clearance of tau protein aggregates:BCL2-associated anthanogene 3(BAG3)is a ubiquitously expressed and highly conserved multi-functional co-chaperone protein involved in m... BCL2-associated anthanogene 3 facilitates the clearance of tau protein aggregates:BCL2-associated anthanogene 3(BAG3)is a ubiquitously expressed and highly conserved multi-functional co-chaperone protein involved in many biological processes that supports cellular homeostasis,including the inhibition of apoptosis by preventing mitochondrial BAX localization(Lin et al.,2022)and the promotion of the degradation of hyperphosphorylated tau aggregates by its interactions with SQSTM1(p62)(Hamano and Mutoh,2022). 展开更多
关键词 inhibition apoptosis tau hyperphosphorylation traumatic brain injury cellular homeostasisincluding preventing mitochondrial bax localization lin BAG p biological processes
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面向车载LiADR点云的杆状地物分类模型研究
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作者 付立哲 《测绘与空间地理信息》 2026年第3期184-186,190,共4页
在道路环境中,杆状结构作为基础设施的核心组件,研究其自动化辨识与分类技术,对于城市数据的实时更新和智慧城市的构建起着重要作用。本文利用车载LiDAR采集的点云数据,提出一种改进引导聚集(Bagging)集成学习方法。首先,对点云数据进... 在道路环境中,杆状结构作为基础设施的核心组件,研究其自动化辨识与分类技术,对于城市数据的实时更新和智慧城市的构建起着重要作用。本文利用车载LiDAR采集的点云数据,提出一种改进引导聚集(Bagging)集成学习方法。首先,对点云数据进行预处理,确保地面与非地面元素的精确区分;接着,提取杆状特征点云,构建特征向量,并据此建立分类模型;最后,对比分析传统单一分类器与本研究中改进Bagging方法在杆状结构分类上的表现。实验成果表明,采用多重投票机制的改进Bagging方法,在杆状地物分类中达到了98.47%的高精度,为点云数据的地理特征分类开辟了新的途径。 展开更多
关键词 车载LiDAR点云 杆状地物 改进Bagging集成 分类模型
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Extracellular BAG3 is elevated in early diffuse systemic sclerosis
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作者 Paul Freedman Margot De Marco +4 位作者 Alessandra Rosati Liberato Marzullo Nicoletta Del Papa Maria Caterina Turco Steven O’Reilly 《Military Medical Research》 2026年第1期169-172,共4页
Dear Editor,Systemic sclerosis(SSc)is an autoimmune connective tissue disease in which there are vascular abnormalities,inflammation,and fibrosis[1].These three characteristics primarily affect the skin and lungs.Of a... Dear Editor,Systemic sclerosis(SSc)is an autoimmune connective tissue disease in which there are vascular abnormalities,inflammation,and fibrosis[1].These three characteristics primarily affect the skin and lungs.Of all the autoimmune rheumatic diseases,SSc has the highest all-cause mortality rate,and the underlying pathogenic processes that mediate disease are still obscure,with wide diff erences in presentation and progression[2,3]. 展开更多
关键词 Systemic sclerosis Bcl-2 associated athanogene-3(BAG3) CYTOKINE Lung disease Stimulator of interferon genes(STING)
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基于GEO数据库探讨翼状胬肉线粒体代谢基因AKT1与ATP5F1及BAG3表达与作用
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作者 王诗逸 王婧 +1 位作者 王华 陈玉萍 《国际眼科杂志》 2026年第3期398-404,共7页
目的:探讨丝氨酸/苏氨酸激酶1(AKT1)、ATP合酶F1亚基(ATP5F1)及Bcl-2相关抗凋亡基因3(BAG3)三者在翼状胬肉发生发展中的表达差异及作用机制。方法:通过GEO数据库获取翼状胬肉相关基因表达数据,筛选差异表达基因;利用String数据库构建蛋... 目的:探讨丝氨酸/苏氨酸激酶1(AKT1)、ATP合酶F1亚基(ATP5F1)及Bcl-2相关抗凋亡基因3(BAG3)三者在翼状胬肉发生发展中的表达差异及作用机制。方法:通过GEO数据库获取翼状胬肉相关基因表达数据,筛选差异表达基因;利用String数据库构建蛋白相互作用(PPI)网络,结合Cytoscape软件筛选核心靶点;采用GO和KEGG通路富集分析线粒体代谢相关通路特征。收集翼状胬肉手术患者的胬肉头部、体部组织标本,HE染色观察两组组织病理形态差异,免疫组化法检测AKT1、ATP5F1、BAG3的蛋白表达水平。结果:GEO数据库分析共筛选出差异表达基因1264个,其中上调585个、下调679个。GO富集分析显示,生物学过程、细胞组分及分子功能层面均存在线粒体相关通路的显著富集;KEGG富集分析以氧化磷酸化、化学致癌-活性氧簇通路差异最为显著。收集翼状胬肉手术患者28例28眼的胬肉头部、体部组织标本,其中男7例7眼,女21例21眼,平均年龄69.32±8.98岁。HE染色结果显示,胬肉头部较体部上皮细胞异型增生更明显、基质纤维排列更紊乱,且炎症细胞浸润更显著。免疫组化结果证实,AKT1、ATP5F1、BAG3在胬肉头部的蛋白表达水平显著低于体部(均P<0.05)。结论:线粒体代谢相关基因AKT1、ATP5F1、BAG3在翼状胬肉中存在明显表达差异,且与病变组织的病理进展密切相关,其可能通过调控线粒体能量代谢参与翼状胬肉的发生发展,为该病的机制研究及靶向治疗提供新的实验依据与思路。 展开更多
关键词 翼状胬肉 GEO数据库 线粒体代谢 丝氨酸/苏氨酸激酶1(AKT1) ATP合酶F1亚基(ATP5F1) Bcl-2相关抗凋亡基因3(BAG3)
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基于机器学习的森林碳储量时空分布模拟
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作者 崔立东 贺丹 +2 位作者 刘玉龙 丛喜东 刘丹 《森林工程》 北大核心 2025年第5期904-911,共8页
森林碳储量是全球碳循环研究的重要内容,应对气候变化具有重要意义。以黑龙江省张广才岭北坡部分区域为研究对象,结合地面观测数据与Landsat TM(thematic mapper)/OLI(operational land imager)传感器数据,采用多种机器学习模型,结合引... 森林碳储量是全球碳循环研究的重要内容,应对气候变化具有重要意义。以黑龙江省张广才岭北坡部分区域为研究对象,结合地面观测数据与Landsat TM(thematic mapper)/OLI(operational land imager)传感器数据,采用多种机器学习模型,结合引导聚集Bagging(bootstrap aggregating)集成学习算法,进行森林碳储量模拟。结果表明,1990—2022年研究区森林碳储量呈现显著增加趋势,年平均碳储量达到(80.77±0.27) Mg C/hm2,且空间分布表现出明显的异质性特征,高碳储量区域集中于平坦或半山坡地带。此外,生长季平均气温与森林碳储量呈极显著的正相关关系(P<0.01),表明气温是影响碳储量变化的主要气候因子。研究结果可为森林碳储量的精准模拟和碳汇管理提供新思路。 展开更多
关键词 遥感 深度学习 Bagging集成学习 气候因子
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基于机器学习算法的脂肪肝预测模型构建
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作者 孙士杰 张琳 +3 位作者 田金举 滕学芹 刘云利 朱士利 《德州学院学报》 2025年第4期49-55,60,共8页
以2018年德州市健康查体职工67660人为研究对象,应用机器学习算法,以脂肪肝是否发生为目标变量,以性别、年龄、吸烟史、饮酒史、体重指数、收缩压、舒张压、空腹血糖、丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、甘油三酯、胆固醇、低密... 以2018年德州市健康查体职工67660人为研究对象,应用机器学习算法,以脂肪肝是否发生为目标变量,以性别、年龄、吸烟史、饮酒史、体重指数、收缩压、舒张压、空腹血糖、丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、甘油三酯、胆固醇、低密度脂蛋白胆固醇酯、高密度脂蛋白胆固醇酯等14个变量为预测变量,构建多个模型并进行比较,选出最佳模型、评价其性能并进行模型部署。共构建13个模型,各模型测试集AUC为0.896~0.950、召回率为0.70~0.83、F1值为0.73~0.83。基于Bagging的神经网络模型为最佳模型,其测试集AUC、召回率、F1值分别为0.950、0.83、0.83,校准曲线、决策曲线表现优良,能应用于脂肪肝筛查场景。 展开更多
关键词 脂肪肝 预测模型 基于Bagging的神经网络
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中国电力需求发展预测及技术创新对策研究
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作者 牛东晓 杜若芸 余敏 《工程管理科技前沿》 北大核心 2025年第4期37-45,共9页
准确预测中长期电力需求对于电力规划者和决策者制定合理的电力系统发展计划、基础设施投资规划、智能电网布局策略至关重要。为了提高中长期电力需求预测的准确性,本文采用XGBoost算法对影响电力需求的关键因素进行筛选。鉴于中长期电... 准确预测中长期电力需求对于电力规划者和决策者制定合理的电力系统发展计划、基础设施投资规划、智能电网布局策略至关重要。为了提高中长期电力需求预测的准确性,本文采用XGBoost算法对影响电力需求的关键因素进行筛选。鉴于中长期电力需求预测数据样本量较小,本文建立基于Bagging自适应集成模型的中长期电力需求预测模型,以解决现有方法样本依赖性强、泛化能力弱的局限性并提高预测的准确性。研究设计了高速发展情景、基准情景、低速发展情景3个模拟情景方案,分情景预测中国2024-2033年电力需求走势。最后,本文展望未来电力技术创新对策,构建以先进技术赋能发电侧、输配电侧和用电侧的电力系统建设框架,推动电力系统向智能化、清洁化、高效化、可持续化和全球化方向发展。本研究为相关领域的政策研究、能源管理和环境保护提供了重要的决策依据,对推动能源体系的脱碳进程以及实现碳中和目标具有重要意义。 展开更多
关键词 电力需求预测 XGBoost算法 Bagging自适应集成模型 电力技术创新对策
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基于Expectile回归森林模型的中国商业银行收益率风险测度研究
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作者 严复雷 余晨曦 张高勋 《科技和产业》 2025年第12期141-151,共11页
有效防范和化解风险是金融业的永恒主题。在当前全球化且复杂严峻的经济金融环境下,提高对商业银行收益率风险的预测能力,并及时采取措施防范化解风险具有重要的现实意义。选取2013年1月至2022年12月A股上市商业银行的月度数据,构建非参... 有效防范和化解风险是金融业的永恒主题。在当前全球化且复杂严峻的经济金融环境下,提高对商业银行收益率风险的预测能力,并及时采取措施防范化解风险具有重要的现实意义。选取2013年1月至2022年12月A股上市商业银行的月度数据,构建非参数Expectile回归森林(ERF)风险预测模型对中国商业银行尾部风险进行测度,并将测度结果与传统的期望分位数回归(ER)模型和Expectile回归树(ERT)模型测度结果进行比较各自的预测性能。结果表明,ERF模型在对商业银行收益率风险测度性能表现出众,在不同风险水平下ERF模型的估计和预测能力显著优于ERT和ER模型;进一步分析发现,四大类商业银行尾部风险预测中误差最小和最大者分别是全国性大型商业银行和地方性农村商业银行,而股份制商业银行和地方性城市商业银行的误差值相当。运用ERF测度商业银行收益率风险为商业银行防范风险提供了重要决策依据,并有助于商业银行风险管理,为金融监管部门提供分类分层监管商业银行收益率风险的重要政策支撑。 展开更多
关键词 Expectile回归森林 商业银行 收益率风险 BAGGING算法
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北斗广播电离层模型精度评估 被引量:2
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作者 鲍任杰 唐成盼 +3 位作者 胡小工 周善石 曹月玲 杨宇泽 《北京航空航天大学学报》 北大核心 2025年第11期3895-3905,共11页
为评估现有全球导航卫星系统(GNSS)中广播电离层模型性能,利用国际GNSS服务(IGS)分析中心提供的事后全球电离层图(GIM)产品,对北斗系统、全球定位系统(GPS)、Galileo系统的广播电离层模型进行了电离层总电子含量(TEC)域及定位域的长期... 为评估现有全球导航卫星系统(GNSS)中广播电离层模型性能,利用国际GNSS服务(IGS)分析中心提供的事后全球电离层图(GIM)产品,对北斗系统、全球定位系统(GPS)、Galileo系统的广播电离层模型进行了电离层总电子含量(TEC)域及定位域的长期精度评估。发现在太阳活动爬坡过程中,北斗Klobuchar八参数模型(BDSK8)、GPS Klobuchar八参数模型(GPSK8)、北斗全球广播电离层模型(BDGIM)及NeQuickG 4种模型的精度均有一定程度的下降,在不同纬度带也表现出不同的特性。结果表明:BDGIM性能最优,在3个纬度带的误差均方根(RMS)均值分别上升至7.27、4.43、4.00 TECU,三维定位误差分别上升至6.62、2.81、3.51 m;BDSK8受太阳活动影响最大,RMS的放大系数可达4~5倍。利用Bagging回归树学习器对各广播电离层模型误差和空间物理参数进行了建模和预报,其中,BDGIM模型预测效果最优,3个纬度带的均方根误差(RMSE)分别为2.13、1.23、1.47 TECU,相对误差(RE)分别为18%、15%、14%;NeQuickG模型次之,RMSE分别为4.60、2.27、1.47 TECU,RE分别为17%、18%、21%;2种Klobuchar模型精度的预报效果不佳。 展开更多
关键词 全球导航卫星系统 广播电离层模型 太阳活动 空间物理参数 Bagging回归
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鄂北地区盒1段岩性差异化模型约束下致密砂岩储层物性分级评价研究 被引量:1
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作者 林行杰 李可赛 +7 位作者 刘岩 刘彦君 展硕硕 雷铠铖 陈婷 郑明明 孙佳琦 王力 《测井技术》 2025年第5期748-761,共14页
鄂尔多斯盆地北部(鄂北)地区盒1段致密砂岩具有低孔隙度低渗透率、岩性复杂、非均质性强等特征,储层岩性难以实现精细化评价以及物性计算精度低。为此,提出了基于Bagging算法岩性差异化模型约束下的物性评价研究方法。首先,基于岩石骨... 鄂尔多斯盆地北部(鄂北)地区盒1段致密砂岩具有低孔隙度低渗透率、岩性复杂、非均质性强等特征,储层岩性难以实现精细化评价以及物性计算精度低。为此,提出了基于Bagging算法岩性差异化模型约束下的物性评价研究方法。首先,基于岩石骨架类型和结构差异划分出4种储层岩性类型并利用测井图版法和皮尔逊相关系数法优选岩性敏感特征曲线,基于Bagging算法建立岩性差异化测井判别模型,实现对储层岩性的精准识别。岩性差异化模型约束物性参数计算并结合射孔层段实测物性数据标定预测物性数据完成Ⅰ、Ⅱ、Ⅲ类储层划分,分河道分小层明确研究区储层分布规律,实现储层物性精细分级评价研究。研究结果表明:①基于Bagging集成算法构建的岩性差异化识别模型显著提升了复杂储层的岩性分类精度,其交叉验证结果表明,模型预测组的岩性识别准确率达到94%。在此基础上,通过岩性差异约束实现了储层参数的高精度计算,孔隙度计算结果与岩心实测数据的平均精度达86.2%,渗透率预测结果的相对误差控制在33%以内。②建立储层物性分级标准,孔隙度>9%且渗透率>0.8 mD*为Ⅰ类储层,Ⅰ类储层孔隙度平均计算精度达89.7%,渗透率预测误差低于27%;孔隙度为[6%,9%]且渗透率≥0.4 mD、孔隙度>9%且渗透率为[0.4,0.8]mD为Ⅱ类储层;孔隙度为[4%,6%)且渗透率≥0.2 mD、孔隙度≥6%且渗透率为[0.2,0.4)mD为Ⅲ类储层。③Ⅰ类储层集中发育在3、4、5号河道的H1-2、H1-1,河道发育连片厚砂体,呈正韵律沉积,沉积颗粒磨圆和分选性更优且粒度更粗,原生孔隙发育,物性优;Ⅱ类储层集中发育在7、8号河道的H1-3,部分发育在H1-1和H1-2;Ⅲ类储层在1、2号河道H1-4发育突出。结论认为,Bagging算法在岩性识别上效果显著,基于岩性差异化模型的物性预测实现了物性更为精细的评价研究,明确了有利勘探层段和河道,为鄂北地区盒1段天然气勘探开发提供了方向。 展开更多
关键词 杭锦旗地区 致密砂岩 BAGGING算法 岩性差异化模型 物性分级评价 储层分布规律
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