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Machine learning and theoretical analysis release the non-linear relationship among ozone,secondary organic aerosol and volatile organic compounds

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Journal of Environmental Sciences 2022年第4期34卷 75-84页

作者： Feng wang Zhongcheng Zhang gen wang Zhenyu wang Mei Li Weiqing Liang Jie Gao Wei wang Da Chen Yinchang Feng Guoliang Shi State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control Tianjin Key Laboratory of Urban Transport Emission ResearchCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research(CLAER) College of Environmental Science and EngineeringNankai UniversityTianjin 300350China State Key Laboratory on Odor Pollution Control Tianjin Academy of Environmental SciencesTianjin 300191China Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air Pollution Jinan University Institute of Mass Spectrometry and Atmospheric EnvironmentGuangzhou 510632China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 510632China Trusted AI System Laboratory College of Computer ScienceNankai UniversityTianjin 300350China Key Laboratory of Civil Aviation Thermal Hazards Prevention and Emergency Response Civil Aviation University of ChinaTianjin 300300China

Fine particulate matter(PM_(2.5))and ozone(O_(3))pollutions are prevalent air quality issues in *** organic compounds(VOCs)have significant impact on the formation of O_(3)and secondary organic aerosols(SOA)contributing PM_(2.5).Herein,we investigated 54 VOCs,O_(3)and SOA in Tianjin from June 2017 to May 2019 to explore the non-linear relationship among O_(3),SOA and *** monthly patterns of VOCs and SOA concentrations were characterized by peak values during October to March and reached a minimum from April to September,but the observed O_(3)was exactly the *** learning methods resolved the importance of individual VOCs on O_(3)and SOA that alkenes(mainly ethylene,propylene,and isoprene)have the highest importance to O_(3)formation;alkanes(C_(n),n≥6)and aromatics were the main source of SOA *** learning methods revealed and emphasized the importance of photochemical consumptions of VOCs to O_(3)and SOA *** formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)calculated by consumed VOCs quantitatively indicated that more than 80%of the consumed VOCs were alkenes which dominated the O_(3)formation,and the importance of consumed aromatics and alkenes to SOAFP were 40.84%and 56.65%,***,isoprene contributed the most to OFP at 41.45%regardless of the season,while aromatics(58.27%)contributed the most to SOAFP in ***,our findings can provide scientific evidence on policymaking for VOCs controls on seasonal scales to achieve effective reduction in both SOA and O_(3).

关键词： VOCs Machine learning Photochemical consumption Ozone formation potential Secondary organic aerosol formation potential

Negative Magnetoresistance Effect in La-Pb-Mn-O Bulk Manganese Oxides

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Chinese Physics Letters 1996年第2期13卷 129-132页

作者： ZHAO Tong-yun LI Min ZHAO Xue-gen wang Fang-wei LI Yun-fei SHEN Bao-gen ZHAO Jian-gao State Key Laboratory of Magnetism Institute of PhysicsAcademia SinicaBeijing 100080

The structure,inagnetic and magnetotransport properties of La_(1-x),Pb_(x) MnO bulk manganese oxides prepared by the standard ceramic techniques were investigated by XRD,VSM,ESM and MR *** sintering condition and the hole doped concentration x have a strong iniluence&n the magnetic properties and niagnetore-sistance *** maximum MR,20%at room temperature under a field of 2 T, was obtained for x=0.4 and the sintered temperature T_(3)=1260℃.The correlation among the structure,magnetic and MR is discussed.

关键词： resistance effect structure

Whole-brain CT Perfusion at Admission and During Delayed Time-window Detects the Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage

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Current Medical Science 2023年第2期43卷 409-416页

作者： Feng you Wen-juan TANG Chao ZHANG Ming-quan YE Xing-gen FANG Yun-feng ZHOU Department of Radiology the First Affiliated Hospital of Wannan Medical CollegeWuhu241001China Department of Radiology Affiliated Hangzhou First People’s HospitalHangzhou310000China Department of Radiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Medical Information Wannan Medical CollegeWuhu241001China Department of Neurosurgery the First Affiliated Hospital of Wannan Medical CollegeWuhu241001China

Objective To evaluate the utility of computed tomography perfusion(CTP)both at admission and during delayed cerebral ischemia time-window(DCITW)in the detection of delayed cerebral ischemia(DCI)and the change in CTP parameters from admission to DCITW following aneurysmal subarachnoid *** Eighty patients underwent CTP at admission and during *** mean and extreme values of all CTP parameters at admission and during DCITW were compared between the DCI group and non-DCI group,and comparisons were also made between admission and DCITW within each *** qualitative color-coded perfusion maps were ***,the relationship between CTP parameters and DCI was assessed by receiver operating characteristic(ROC)*** With the exception of cerebral blood volume(P=0.295,admission;P=0.682,DCITW),there were significant differences in the mean quantitative CTP parameters between DCI and non-DCI patients both at admission and during *** the DCI group,the extreme parameters were significantly different between admission and *** DCI group also showed a deteriorative trend in the qualitative color-coded perfusion *** the detection of DCI,mean transit time to the center of the impulse response function(Tmax)at admission and mean time to start(TTS)during DCITW had the largest area under curve(AUC),0.698 and 0.789,*** Whole-brain CTP can predict the occurrence of DCI at admission and diagnose DCI during *** extreme quantitative parameters and qualitative color-coded perfusion maps can better reflect the perfusion changes of patients with DCI from admission to DCITW.

关键词： aneurysmal subarachnoid hemorrhage delayed cerebral ischemia admission time window computed tomography perfusion

Expressing an (E)-β-farnesene synthase in the chloroplast of tobacco affects the preference of green peach aphid and its parasitoid

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Journal of Integrative Plant Biology 2015年第9期57卷 770-782页

作者： gen-Ping wang Xiu-Dao Yu Jia Fan Cheng-She wang Lan-Qin Xia College of Agronomy Northwest A&F University/State Key Laboratory of Crop Stress Biology in Arid Areas Institute of Crop Sciences the Chinese Academy of Agricultural Sciences (CAAS) School of Life Science and Technology Nanyang Normal University Institute of Crop Protection the Chinese Academy of Agricultural Sciences (CAAS)

(E)-b-Farnesene (EbF) synthase catalyses the production of EbF, which for many aphids is the main or only component of the alarm pheromone causing the repellence of aphids and also functions as a kairomone for aphids’ natural enemies. Many plants possess EbF synthase genes and can release EbF to repel aphids. In order to effectively recruit the plant-derived EbF synthase genes for aphid control, by using chloroplast transit peptide (CTP) of the small subunit of Rubisco (rbcS) from wheat (Triticum aestivum L.), we targeted AabFS1, an EbF synthase gene from sweet wormwood (Artemisia annua L.), to the chloroplast of tobacco to generate CTP t AabFS1 transgenic lines. The CTP t AabFS1 transgenic tobacco plants could emit EbF at a level up to 19.25 ng/day per g fresh tissues, 4–12 fold higher than the AabFS1 transgenic lines without chloroplast targeting. Furthermore, aphid/parasitoid behavioral bio-assays demonstrated that the CTP t AabFS1 transgenic tobacco showed enhanced repellence to green peach aphid (Myzus persicae) and attracted response of its parasitoid Diaeretiella rapae, thus affecting aphid infestation at two trophic levels. These data suggest that the chloroplast is an ideal subcellular compartment for metabolic engineering of plant-derived EbF synthase genes to generate a novel type of transgenic plant emitting an alarm pheromone for aphid control.

关键词： Aphid chloroplast Diaeretiella rapae (E)b-farnesene synthase Myzus persicae tobacco

Spectrofluorometry of Ions and Small Molecules Based on Conformational Changes of Specific Oligonucleotides with o-Phthalaldehyde-β-mercaptoethanol

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Chemical Research in Chinese Universities 2010年第3期26卷 360-365页

作者： LIAO Qie-gen wang Jian LONG Yun-fei LI Yuan-fang Key Laboratory of Lumineseence and Real-Time Analysis Ministry of Education College of Chemistry and Chemical Engineering Southwest University Chongqing 400715 P. R. China Key Laboratory of Quality and Safety of Agricultural Products Jiangxi Academy of Agricultural Sciences Nanchang 330200 R R. China

Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively applied to fluorescent detection of amino compounds based on the reaction of primary amino-group, herein we proposed a general spectrofluorometry for ions and small molecules due to conformational changes upon ligand binding taking K^＋ and ATP as examples. In a borate controlled buffer medium, telomere DNA could react with OPAME, giving a thio-subtituted isoindole compound with strong fluorescence emission at 455 nm when excited at 340 nm. It was found that however, the fluorescence emission was greatly reduced in the presence of K^＋ since the formation of the quadruplex structure inhibits the reaction activity of amino-groups of telomere DNA. In order to testify the general application of OPAME reagent based on the conformational change of oligonucleotides, we further proposed a sensitive method of ATP based on its highly selective interaction with ATP-aptamer. The above mentioned applications show that the spectrofluorometry with the aid of OPAME reagent is simple, label free that is expected to be potentially general for DNA conformational change-based target detection.

关键词： Aptamer o-Phthalaldehyde β-Mercaptoethanol K^+ Adenosine-5′-triphosphoric acid

Effect of Water Deficit on Self-thinning Line in Spring Wheat （Triticum aestivum L.） Populations

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Journal of Integrative Plant Biology 2006年第4期48卷 415-419页

作者： Jing Liu Liang Wei Chun-Ming wang gen-Xuan wang Xiao-Ping Wei Key Laboratory of Arid and Grassland Ecology Lanzhou University Ministry of Education Lanzhou 730000 China College of Life Sciences Zhejiang University Hangzhou 310027 China School of Life Sciences Lanzhou University Lanzhou 730000 China

Monocultures of spring wheat （Triticum aestivum L.） were grown at overcrowded densities （10 000 and 3 000 plants per m^2） under well-watered and water-stressed conditions to investigate the effects of water deficits on self-thinning. The results showed that density reduction in water-stressed populations was delayed compared with that In well-watered populations. Populations grown In well-watered conditions conformed to the -3/2- power law. Compared with the well-watered condition, there was no significant decrease of the self-thinning line under water-stressed conditions In this experiment, although the rate of average shoot blomass accumulatlon decreased. This result Implied that the exponent of the -3/2-power equation Is not as sensitive as the rate of average shoot blomass accumulation to water stress. Further analysis indicated that, In each density treatment, the lines of the height versus shoot blomass relationships did not differ significantly between the two water conditions. However, the Intercepts of the height versus shoot blomass relationships were greater In the higher-density populations （10 000/m^2） than those In the lower-density populations （3 000/m^2）. These results showed that water deficit did not change plant geometry In this experiment. That Is to say, shoot competition for light remains constant at a given blomass, although root competition for water becomes more serious In water deficit conditions. Based on these results and previous reports we propose that, to affect the thinning line slope, changes In symmetric competition are not as efficient as changes In asymmetric competition.

关键词： -3/2-power rule competition density self-thinning water deficit.

Ultrasonicwave-assisted tandem-reaction for synthesis of symmetrical vicinal diamines

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Chinese Chemical Letters 2007年第12期18卷 1469-1470页

作者： gen Rong Qiang Xiang Mei Wu Qin wang Wen Pei College of Chemical Engineering and Materials Zhejiang University of Technology Hangzhou 310014 China

A practical synthesis of symmetrical vicinal diamines with broad chemistry scope is described. The key step is the ultrasonicwave promoted tandem-reaction, two-step reaction sequence combining Mannich double condensations with benzo- triazole, glyoxal and primary or secondary amines and reduction of the bis（benzotriazole）-adducts with sodium borohydride proceeded smoothly in tetrahydrofuran in high yield at room temperature.

关键词： Vicinal diamine Benzotriazole Glyoxal Mannich reaction Synthesis

XRCC1 Arg399Gln and clinical outcome of platinum-based treatment for advanced non-small cell lung cancer:a meta-analysis in 17 studies

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第11期13卷 875-883页

作者： Jian CHEN Qing-wei ZHAO gen-ming SHI Lin-run wang Department of Pharmacy the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Medical Oncology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： XRCCl polymorphism is a research hotpot in individual treatment for non-small cell lung cancer （NSCLC）. To obtain the association between XRCC1 polymorphism and clinical outcome of platinum-based treatment for NSCLC, a meta-analysis was conducted. Methods： Databases including PubMed, Embase, Cochrane, and Chi- nese National Knowledge Infrastructure （CNKI） were searched for publications that met the inclusion criteria. A fixed effect model was used to estimate pooled odds ratio （OR） and hazard ratio （HR） with 95% confidence interval （CI） for the association between XRCC1 Arg399GIn and response or survival of platinum-based treatment for advanced NSCLC. A chi-squared-based Q-test was used to test the heterogeneity hypothesis. Egger＇s test was used to check publication bias. Results： Seventeen published case-control studies that focus on the association between XRCC1 Arg399Gln and response or survival of platinum-based treatment for advanced NSCLC in 2 256 subjects were included in this meta-analysis, of whom 522 were AA genotypes （23.2% frequency）, 916 AG genotypes （40.6% frequency）, and 818 GG genotypes （36.2% frequency）. The overall response rate （ORR） was 45.2% （110/243） for AA genotype pa- tients, 29.9% for AG genotype （73/244）, and 30.7% for GG genotype （124/403）. The heterogeneity test did not show any heterogeneity and the Egger＇s test did not reveal an obvious publication bias among the included studies. The meta-analysis indicated that AA genotype patients presented higher response rates toward platinum drug treatment compared with G model （GG＋GA） patients （GG vs. AA model： OR=0.489, 95% CI 0.266-0.900, P=0.021; AG vs. AA model： OR=0.608, 95% CI 0.392-0.941, P=0.026; GA＋AA vs. GG model： OR=1.259, 95% CI 0.931-1.701, P=-0.135; GG＋GA vs. AA model： OR=0.455, 95% CI 0.313-0.663, P=0.0001）. However, no evidence validates XRCC1 associates with the survival following platinum drug therapy. Conclusions： Our meta-analysis suggested that XRCC1 Arg399GIn is r

关键词： Meta-analysis XRCC1 Arg399Gln Non-small cell lung cancer (NSCLC) Response Survival

Effects of pre-strain and baking parameters on the microstructure and bake-hardening behavior of dual-phase steel

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International Journal of Minerals,Metallurgy and Materials 2014年第8期21卷 766-771页

作者： Chun-fu Kuang Shen-gen Zhang Jun Li Jian wang Hua-fei Liu School of Materials Science and Engineering University of Science and Technology Beijing Research Institute Baoshan Iron and Steel Co. Ltd.

In a typical process, C-Mn steel was annealed at 800℃ for 180 s, and then cooled rapidly to obtain the ferrite-martensite microstructure. After pre-straining, the specimens were baked and the corresponding bake-hardening （BH） values were determined as a function of pre-strain, baking temperature, and baking time. The influences ofpre-strain, baking temperature and baking time on the microstructure evolution and bake-hardening behavior of the dual-phase steel were investigated systematically. It was found that the BH value apparently increased with an increase in pre-strain in the range from 0 to 1%; however, increasing pre-strain from 1% to 8% led to a decrease in the BH value. Furthermore, an increase in baking temperature favored a gradual improvement in the BH value because of the formation of Cottrell atmosphere and the precipitation of carbides in both the ferrite and martensite phases. The BH value reached a maximum of 110 MPa at a baking temperature of 300℃. Moreover, the BH value enhanced significantly with increasing baking time from 10 to 100 min.

关键词： dual-phase steel pre-strain baking treatment microstructure hardening