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An improved gas chromatography for rapid measurement of CO2, CH4 and N2O

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Journal of Environmental Sciences 2006年第1期18卷 162-169页

作者： WANG Ying-hong WANG Yue-si SUN Yang XU Zhong-jun LIU Guang-ren Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Combining improved injector, gas line and valve-driving modules, a GC equipped with FID and ECD, could simultaneously measure CH4, CO2 and N2O in an air sample within 4 min. Test results showed that the system has high sensitivity, resolution and precision; the linear response range of the system meets the requirement of in situ flux measurements. Thus, the system is suitable for monitoring fluxes of main greenhouse gases in terrestrial ecosystem since it is easy to use, efficacious, stable and reliable to collect data.

关键词： GC valve emission of greenhouse gases ecosystem

Bio-inspired Polyimine Copolymers： Facial Integration with High Content Variability and Extremal Transitions of Mechanical Properties

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Journal of Bionic Engineering 2017年第1期14卷 119-129页

作者： si Zhang Yanting Lv Long Zheng Jiayi Li Song Liang Zhenning Liu Luquan ren Key Laboratory of Bionic Engineering (Ministry of Education) Jilin University Changchun 130022 China

Natural composites have inspired the fabrication of various biomimetic composites that have achieved enhancement on certain mechanical performance. Herein, a facial approach enabled by recent advances in polyimine chemistry has been developed to fabricate bio-inspired hard-soft-integrated copolymers from two polyimines （i.e. PI-H and PI-S） with hardness differential. Subsequent evaluations of multiple mechanical properties on the bio-inspired copolymers with PI-S contents of full-range variability （0 wt%-100 wt%） have revealed extremal transitions for friction coefficients, impact strengths and tensile moduli. More interestingly, the minimum points of friction coefficients show a deformation-resisting response toward the change of applied loads, but not for the altered sliding speeds, suggesting a more significant role of load in determining the optimal anti-friction composition of the hard-soft integrated copolymers. These trends have been further corroborated by scanning electron microscopy of the worn specimens. Together these results have demonstrated that full-range extremal tran- sitions exist on multiple mechanical properties for hard-soft-integrated copolymers, providing valuable insights to the design and fabrication of composite polymers for many applications. The polyimine-based approach outlined here also affords a convenient method to tune the ratio of two components in the copolymers within the full range of 0 wt%-100 wt%, enabling quick integration with high content variability.

关键词： bio-inspiration polyimine mechanical properties extremal transition content variability

Key Genes Involved in the Beneficial Mechanism of Hyperbaric Oxygen for Glioblastoma and Predictive Indicators of Hyperbaric Oxygen Prolonging Survival in Glioblastoma Patients

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Current Medical Science 2024年第5期44卷 1036-1046页

作者： Zi-qi ren ren-dong WANG cong WANG Xiao-hui ren Dong-guo LI Ya-ling LIU Qiu-hong YU Department of Hyperbaric Oxygen Beijing Tiantan HospitalCapital Medical UniversityBeijing100070China School of Biomedical Engineering Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical ApplicationCapital Medical UniversityBeijing100069China Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing100070China

Objective The prognosis of glioblastoma is poor,and therapy-resistance is largely attributed to intratumor *** oxygen(HBO)effectively alleviates ***,the sole role of HBO in glioblastoma remains *** previously reported that HBO can promote apoptosis,shorten protrusions,and delay growth of glioblastoma,but the molecular mechanism is *** aimed to test candidate genes in HBO-exposed glioblastoma cells and to analyze their correlation with the survival of glioblastoma *** Glioblastoma cell lines exposed to repetitive HBO or normobaric air(NBA)were collected for RNA isolation and microarray data *** analysis,KEGG pathway analysis and survival analysis of the differentially expressed genes(DEGs)were *** HBO not only inhibited hypoxia-inducing genes including CA9,FGF11,PPFIA4,TCAF2 and SLC2A12,but also regulated vascularization by downregulating the expression of COL1A1,COL8A1,COL12A1,RHOJ and FILIP1L,ultimately attenuated hypoxic microenvironment of *** attenuated inflammatory microenvironment by reducing the expression of NLRP2,CARD8,MYD88 and *** prevented metastasis by downregulating the expression of NTM,CXCL12,CXCL13,CXCR4,CXCR5,CDC42,IGFBP3,IGFBP5,GPC6,MMP19,ADAMTS1,EFEMP1,PTBP3,NF1 and *** upregulated the expression of BAK1,PPIF,DDIT3,TP53I11 and FAS,whereas downregulated the expression of MDM4 and siVA1,thus promoting *** upregulated the expression of CDC25A,MCM2,PCNA,RFC33,DSCC1 and CDC14A,whereas downregulated the expression of ASNS,CDK6,CDKN1B,PTBP3 and MAD2L1,thus inhibiting cell cycle *** these DEGs,17 indicator-genes of HBO prolonging survival were *** HBO is beneficial for *** patients with these predictive indicators may prolong survival with HBO *** potential therapeutic targets especially COL1A1,ADAMTS1 and PTBP3 deserve further validation.

关键词： glioblastoma hyperbaric oxygen differentially expressed gene gene enrichment analysis survival analysis

Optimizing agronomic practices for closing rapeseed yield gaps under intensive cropping systems in China

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Journal of Integrative Agriculture 2020年第5期19卷 1241-1249页

作者： ZHANG Zhi cong Ri-huan ren Tao LI Hui ZHU Yun LU Jian-wei College of Resources and Environment Huazhong Agricultural University/Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtze River)Ministry of Agriculture and Rural AffairsWuhan 430070P.R.China Key Laboratory of Fertilization from Agricultural Wastes Ministry of Agriculture and Rural Affairs/Institute of Plant Protection and Soil FertilizerHubei Academy of Agricultural SciencesWuhan 430064P.R.China

A yield gap analysis for rapeseed(Brassica napus L.) is critical to meeting the oil demand by identifying yield potential and yield constraints. In this study, potential yield(Y_p), attainable yield(Y_(att)), and actual yield(Y_(act)) for winter rapeseed were determined in five different zones of China. A boundary line approach was adopted to calculate Y_p, based on a large-scale field experimental database. A meta-analysis was conducted on the data obtained from 118 published studies to evaluate the effects of agronomic factors on rapeseed yield. The main results indicated that farmers only achieved 37–56% of the yield potential across the zones. The low altitude areas(L-URY) and lower reaches(LRY) of the Yangtze River Basin(YRB), China had high yield levels. The total yield gap was 1 893 kg ha^(–1), due to the agronomic management factors, environmental factors, and socioeconomic factors. The meta-analysis showed that weed control and drainage were the best management practices to improve yields(45.6 and 35.3%, respectively), and other practices improved yields by 17.1–21.6%. Consequently, to narrow the yield gap over the short term, the study could focus on techniques that are easily implemented to farmers.

关键词： rapeseed yield gap potential yield boundary line meta-analysis Yangtze River Basin

Prediction of office building electricity demand using artificial neural network by splitting the time horizon for different occupancy rates

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Energy and AI 2021年第3期5卷 159-170页

作者： si Chen Yaxing ren Daniel Friedrich Zhibin Yu James Yu James Watt School of Engineering the University of GlasgowGlasgow G128QQUK School of Engineering The University of EdinburghEdinburgh EH93FBUK SP Distribution PLC Glasgow G720HTUK

Due to the impact of occupants’activities in buildings,the relationship between electricity demand and ambient temperature will show different trends in the long-term and short-term,which show seasonal variation and hourly variation,*** makes it difficult for conventional data fitting methods to accurately predict the long-term and short-term power demand of buildings at the same *** order to solve this problem,this paper proposes two approaches for fitting and predicting the electricity demand of office *** first proposed approach splits the electricity demand data into fixed time periods,containing working hours and non-working hours,to reduce the impact of occupants’*** finding the most sensitive weather variable to non-working hour electricity demand,the building baseload and occupant activities can be predicted *** second proposed approach uses the artificial neural network(ANN)and fuzzy logic techniques to fit the building baseload,peak load,and occupancy rate with multi-variables of weather *** this approach,the power demand data is split into a narrower time range as no-occupancy hours,full-occupancy hours,and fuzzy hours between them,in which the occupancy rate is varying depending on the time and weather *** proposed approaches are verified by the real data from the University of Glasgow as a case *** simulation results show that,compared with the traditional ANN method,both proposed approaches have less root-mean-square-error(RMSE)in predicting electricity *** addition,the proposed working and non-working hour based regression approach reduces the average RMSE by 35%,while the ANN with fuzzy hours based approach reduces the average RMSE by 42%,comparing with the traditional power demand prediction *** addition,the second proposed approach can provide more information for building energy management,including the predicted baseload,peak load,and occupancy rate,without r

关键词： Building energy Electricity demand prediction Statistical modelling Artificial neural network Occupancy rate

Molecular cloning,characterization and promoter analysis of LbgCWIN1 and its expression profiles in response to exogenous sucrose during in vitro bulblet initiation in lily

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Horticultural Plant Journal 2024年第2期10卷 545-555页

作者： cong Gao Shiqi Li Yunchen Xu Yue Liu Yiping Xia Ziming ren Yun Wu Genomics and Genetic Engineering Laboratory of Ornamental Plants Institute of Landscape ArchitectureCollege of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiang 310058China Laboratory of Flower Bulbs Department of Landscape ArchitectureSchool of Civil Engineering and ArchitectureZhejiang Sci-Tech UniversityHangzhouZhejiang 310018China

Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch.

关键词： Lilium brownii var.giganteum LbgCWIN1 Phylogenetic analysis Promoter analysis Bulblet initiation

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本质与价值:数字时代广告本体的再认识

武汉大学学报（哲学社会科学版） 2025年第1期78卷 125-132页

作者：姚曦任文姣武汉大学新闻与传播学院湖北武汉430072 武汉大学媒体发展研究中心

用传播的方式促进从生产到消费转换的行为皆为存在意义上的广告,广告的本体是本质与价值的统一。本体的坚守要建立开放的认识观,在不变的广告本质中解释变化着的广告形态,而非用未触及本体的不确定认识窄化新的广告事实。彰显广告价值... 详细信息

用传播的方式促进从生产到消费转换的行为皆为存在意义上的广告,广告的本体是本质与价值的统一。本体的坚守要建立开放的认识观,在不变的广告本质中解释变化着的广告形态,而非用未触及本体的不确定认识窄化新的广告事实。彰显广告价值需深耕数字广告实践,用创意提升广告的社会吸引力,建构多主体参与的沟通网络。彰显广告价值还需要在理论层面,以本体观为支点,立足于本土广告实践,重新组织数字广告研究范畴,使用大数据技术与混合研究法探究新问题,为广告学知识体系的建构提供框架与方向。

关键词：广告广告本质广告价值广告本体

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Sensitivity analysis to reduce duplicated features in ANN training for district heat demand prediction

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Energy and AI 2020年第2期2卷 63-73页

作者： si Chen Yaxing ren Daniel Friedrich Zhibin Yu James Yu James Watt School of Engineering The University of GlasgowGlasgow G128QQUK School of Engineering The University of EdinburghEdinburgh EH93FBUK SP Distribution PLC Glasgow G720HTUK

Artificial neural network(ANN)has become an important method to model the nonlinear relationships between weather conditions,building characteristics and its heat *** to the large amount of training data re-quired for ANN training,data reduction and feature selection are important to simplify the ***,in building heat demand prediction,many weather-related input variables contain duplicated *** paper develops a sensitivity analysis approach to analyse the correlation between input variables and to detect the variables that have high importance but contain duplicated *** proposed approach is validated in a case study that predicts the heat demand of a district heating network containing tens of buildings at a university *** results show that the proposed approach detected and removed several unnecessary input variables and helped the ANN model to reduce approximately 20%training time compared with the traditional methods while maintaining the prediction *** indicates that the approach can be applied for analysing large num-ber of input variables to help improving the training efficiency of ANN in district heat demand prediction and other applications.

关键词： Building heat demand prediction Statistical modelling Artificial neural network Sensitivity analysis Feature selection

Quantum dynamical resource theory under resource non-increasing framework

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Chinese Physics B 2023年第4期32卷 184-192页

作者：杨思忍于长水 School of Physics Dalian University of TechnologyDalian 116024China

We define the resource non-increasing(RNI)framework to study the dynamical resource *** this definition,we propose several potential quantification candidates under various free operation *** explicit demonstrations,we quantify the quantum dynamical coherence in the scenarios with and without post-selective ***,we show that the maximally incoherent operations(MIO)and the incoherent operations(IO)in the static coherence resource theory are free in the sense of dynamical *** also provide operational meanings for the measures by the quantum discrimination ***,for the dynamical total coherence,we also present convenient measures and give the analytic calculation for the amplitude damping channel.

关键词： quantum resource theory quantum channels quantum coherence