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Relationship Between Leaf C/N Ratio and Insecticidal Protein Expression in Bt Cotton as Affected by High Temperature and N Rate

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Journal of Integrative Agriculture 2014年第1期13卷 82-88页

作者： ZHANG Xiang LU Chun-hua CHEN yuan WANG Gui-xia CHEN yuan CHEN De-hua Jiangsu Provincial Key Laboratory of Crops Genetics and Physiology Yangzhou University Yangzhou 225009 P.R.China Department of Soil and Crop Sciences Texas A&M University College Station 77843 USA

Expression of insecticidal protein for transgenic Bacillus thuringiensis （Bt） cotton is unstable and related to nitrogen metabolism. The objective of this study was to investigate the relationship between leaf carbon nitrogen ratio （C/N） and insecticidal efficacy of two Bt cotton cultivars. C/N ratio and Bt protein content were both measured at peak square period and peak boll period respectively under 5-7 d high temperature and different nitrogen fertilizer rates on the Yangzhou University Farm and the Ludong Cotton Farm, China. All plants were grown in field. The results showed that the C/N ratio enhanced slightly and the Bt protein content remained stable at peak square period, but significant increases for the C/N ratio and decreases markedly for the leaf Bt protein concentration were detected at the peak boll period. The similar patterns at the two growth periods were found for the leaf C/N ratio and Bt protein content by different N fertilizer treatments. When nitrogen rate was from 0 to 600 kg ha-l, the C/N ratio was reduced by 0.017 and 0.006 for Sikang 1 and Sikang 3 at peak square period, compared to the 1.350 to 1.143 reduction for Sikang 1 and Sikang 3 at peak boll period, respectively. Correspondingly, the leaf Bt protein contents were bolstered by 2.6-11.8 and 26.9-36.9% at the two different growth periods, respectively. The results suggested that enhanced C/N ratio by high temperature and nitrogen application may result in the reduction of inseetiocidal efficacy in Bt cotton, especially in peak boll period.

关键词： Bt cotton C/N ratio Bt protein insecticidal efficacy

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Microstructural characteristics and aging response of Zn-containing Al-Mg-Si-Cu alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 659-664页

作者： yuan-hua Cai Cong Wang Ji-shan Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Al-Mg-Si-Cu alloys with and without Zn addition were fabricated by conventional ingot metallurgy method. The microstructures and properties were investigated using optical microscopy （OM）, field emission scanning electron microscopy （FE-SEM）, transmission electron microscopy （TEM）, tensile test, hardness test, and electrical conductivity measurement. It is found that the as-cast A1-Mg-Si-Cu-Zn alloy is composed of coarse dendritic grains, long needle-like ~/5-A1FeSi white intermetallics, and Chinese script-like a-A1FeSi compounds. During high temperature homogenization treatment, only harmful needle-like ^-A1FeSi phase undergoes fragmentation and spheroidizing at its tips, and the destruc- tive needle-like 5-phase does not show any morphological and size changes. Phase transitions from ^-A1FeSi to ^-A1FeSi and from 6-A1FeSi to [3-A1FeSi are also not found. Zn addition improves the aging hardening response during the former aging stage and postpones the peak-aged hardness to a long aging time. In T4 condition, Zn addition does not obviously increase the yield strength and decrease the elongation, but it markedly improves paint-bake hardening response during paint-bake cycle. The addition of 0.5wt% Zn can lead to an increment of 99 MPa in yield strength compared with the value of 69 MPa for the alloy without Zn after paint-bake cycle.

关键词： aluminum alloys zinc hardening mechanical properties microstructure

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TOWARDS EXPLORING WHEN AND WHAT PEOPLE REVIEWED FOR THEIR ONLINE SHOPPING EXPERIENCES

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Journal of Systems Science and Systems Engineering 2018年第3期27卷 367-393页

作者： Liangqiang Li hua yuan Yu Qian Peiji Shao School of Management and Economics University of Electronic Science and Technology of China Chengdu 611731 China

Web 2.0 technologies have attracted an increasing number of people with various backgrounds to become active online writers and viewers. As a result, exploring reviewers＇ opinions from a huge number of online reviews has become more important and simultaneously more difficult than ever before. In this paper, we first present a methodological framework to study the ＂purchasing-reviewing＂ behavior dynamics of online customers. Then, we propose a review-to-aspect mapping method to explore reviewers＇ opinions from the massive and sparse online reviews. The analytical and experimental results with real data demonstrate that online customers can be sectioned into groups in accordance with their reviewing behaviors and that people within the same group may have similar reviewing motivations and concerns for an online shopping experience.

关键词： E-commerce online review review dynamics opinion mining

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Micromechanical properties of poly(N-isopropylacrylamide)hydrogel microspheres determined using a simple method

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Particuology 2015年第2期13卷 164-172页

作者： Mei yuan Xiaojie ju Rui Xie Wei Wang Liangyin Chu School of Chemical Engineering Sichuan University

Temperature-responsive poly（N-isopropylacrylamide）（PNIPAM） hydrogel microspheres have attracted extensive attention because of their promising diverse biomedical applications. A quantitative understanding of the micromechanical properties of these microspheres is essential for their practical application. Here, we report a simple method for the characterization of the elastic properties of PNIPAM hydrogel microspheres. The results show that PNIPAM hydrogel microspheres exhibit elastic deformation and the obtained force-deformation experimental data fits the Hertz theory well. The moduli of elasticity of the PNIPAM hydrogel microspheres prepared under different conditions were systematically investigated in this work for the first time. The PN1PAM hydrogel microsphere composition significantly affects their micromechanical properties and their temperature sensitivity behavior. PNIPAM hydrogel microspheres with a larger equilibrium volume change have a lower modulus of elasticity. The modulus of elasticity of the PNIPAM hydrogel microspheres at body temperature （37 ℃, above the lower critical solution temperature （LCST） of PNIPAM） is much higher than that at room temperature （25 ℃, below the LCST of PNIPAM） because ofthermo-induced volume shrinkage and an increase in stiffness. These results provide valuable guidance for the design of smart materials for practical biomedical applications. Moreover, the simple microcompression method presented here also provides a versatile way to investigate the micromechanical properties of microscopic biomedical materials.

关键词： Poly(N-isopropylacrylamide) Microspheres Micromechanical properties Modulus of elasticity Temperature-responsive volume change Lower critical solution temperature

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The dynamic response and damage models of rebar reinforced polymer slabs subjected to contact and near-field explosions

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Defence Technology（防务技术） 2023年第10期28卷 330-342页

作者： Hao-nan Zhao Hong-yuan Fang Xiao-hua Zhao Yellow River Laboratory Zhengzhou UniversityZhengzhou450001China

Non aqueous reactive polymer materials produced by the reaction of isocyanate and polyol have been widely used in infrastructure construction,which may be subjected to explosion loads during complex service *** blast response of composite materials is a crucial aspect for applications in engineering structures potentially subjected to extreme *** this work,damage caused to rebar reinforced polymer slabs by surface explosive charges was studied experimentally and numerically.A total of 6 field tests were carried out to investigate the performances of the failure modes of rebar reinforced polymer slabs under contact and near-field *** influence of explosive quantity(10-40 g)and stand-off distances(0-20 cm)at the damage modes were *** results show that the failure modes of rebar reinforced polymer slabs under near-field explosion mainly were bending and surface spalling,while under the impact of contact explosion,the failure modes were craters of the top surface,spalling of the bottom surface,and middle ***,a detailed fully coupled model was developed and validated with the test *** influences of explosive quantity and slab thickness on rebar reinforced polymer slabs under contact explosion were *** on this,the calculation formula between breach diameter,explosive quantity,and slab thickness is fitted.

关键词： Reinforced polymer slab Numerical investigations Empirical prediction Damage models

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Risk Factors of Precancerous Gastric Lesions in A Population at High Risk of Gastric Cancer

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Chinese Journal of Cancer Research 2010年第4期22卷 267-273页

作者： Jian Liu Li-Ping Sun Yue-hua Gong yuan yuan Cancer Institute The First Affiliated Hospital China Medical University Shenyang 110001

Objective： In cancer prevention, the targeting of precancerous lesions has been recognized as the most promising method. However, little attention has been paid to the risk factors of precancerous gastric lesions, especially in rural China where there is high prevalence of precancerous gastric lesions. We therefore conducted a cross-sectional study in Liaoning province, China, to investigate the potential risk and protective factors of these precancerous gastric lesions. Methods： A total of 1,179 subjects with high risk of gastric cancer from Zhuanghe County were included in this study. Standard questionnaires were used in collecting epidemiological factors and the data were then analyzed by the unconditional logistic regression model. Results： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects, and the association of smoking or drinking and the precancerous gastric lesions increased in strength with the daily consumption and duration. As the factors such as age, gender, smoking, alcohol were controlled, a multivariable analysis revealed that there was a significant correlation between the deep-fry food intake and the gastric epithelial dysplasia with the odds ratio （OR） of 1.78 [95% confidence interval （CI）： 1.01-3.12]. Garlic eating was shown to confer protection against the development of gastric ulcer （OR=0.55, 95% CI： 0.33-0.92）. Conclusion： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects. Deep-fry food intake might be one of the risk factors for the precancerous gastric lesions and garlic eating was shown to confer protection against the development of gastric ulcer among rural Chinese population.

关键词： Risk factors Precancerous gastric lesions High risk of gastric cancer

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Serum pepsinogen levels and their influencing factors:A population-based study in 6990 Chinese from North China

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World Journal of Gastroenterology 2007年第48期13卷 6562-6567页

作者： Li-Ping Sun Yue-hua Gong Lan Wang yuan yuan Cancer Institute First Affiliated Hospital China Medical University Shenyang 110001 Liaoning Province China

AIM: To explore the essential characteristics of serum pepsinogen (PG) levels in Chinese people, by analyzing the population-based data on the serum levels of PG Ⅰ and Ⅱ and the PGⅠ/Ⅱ ratio, and their influencing factors in Chinese from North China. METHODS: A total of 6990 subjects, who underwent a gastric cancer screening in North China from 1997 to 2002, were collected in this study. Serum pepsinogen levels were measured by enzyme-linked immunosorbent assay (ELISA). H pylori status was determined by histological examination and H pylori-IgG ELISA. The cut-off point was calculated by using receiving operator characteristics (ROC) curves. Factors linked to serum PG Ⅰ/Ⅱ ratio were identified using a multivariate logistic regression. RESULTS: The serum PGⅠ and PGⅡ levels were significantly higher in males than in females (95.2 μg/L vs 79.7 μg/L, P < 0.01; 12.1 μg/L vs 9.4 μg/L, P < 0.01), PGⅠ/Ⅱ ratio was significantly lower in males than in females (7.9 vs 8.3, P < 0.01). The PG Ⅰ/Ⅱ ratio decreased significantly in the aged groups following the progression of gastric mucosa from normal to non-atrophic and atrophic lesions (10.4, 8.8, and 6.6, respectively). The serum PGⅠand Ⅱ levels were significantly higher in patients with H pylori infection than in those without H pylori infection (88.7 μg/L vs 81.4 μg/L, P < 0.01; 11.4 μg/L vs 8.4 μg/L, P < 0.01), while the PGⅠ/Ⅱ ratio was significantly lower in patients with H pylori infection than in those without H pylori infection (7.7 vs 9.6, P < 0.01). For patients with atrophic lesions, the area under the PGⅠ/Ⅱ ROC curve was 0.622. The best cut-off point for PGⅠ/Ⅱ was 6.9, with a sensitivity of 53.2%, and a specificity of 67.5%. Factors linked to PGⅠ/Ⅱ were sensitive to identified PG using a multinomial logistic regression relying on the following inputs: males (OR: 1.151, 95% CI: 1.042-1.272, P = 0.006), age ≥ 61 years (OR: 1.358, 95% CI: 1.188-1.553, P = 0.000), atrophic lesion (OR: 2.075, 95% CI: 1.870-2.302, P = 0.000)

关键词： Pepsinogen Gastric cancer Helicobacter pylori Screening

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SPME-Arrow/GC-MS结合多元统计分析研究不同批次爆珠香精组分差异

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分析测试学报 2025年第1期44卷 135-144页

作者：刘琪张华叶远青刘昌泽袁益来廖惠云吴君章江苏中烟工业有限责任公司江苏南京210019 广东中烟工业有限责任公司广东广州510385

以箭型固相微萃取(SPME-Arrow)为样品萃取手段,通过优化萃取头种类、氯化钠添加量、萃取温度、平衡时间及萃取时间等条件,构建了高效鉴定爆珠香精中挥发性及半挥发性化合物的箭型固相微萃取结合气相色谱-质谱联用(SPME-Arrow/GC-MS)法... 详细信息

以箭型固相微萃取(SPME-Arrow)为样品萃取手段,通过优化萃取头种类、氯化钠添加量、萃取温度、平衡时间及萃取时间等条件,构建了高效鉴定爆珠香精中挥发性及半挥发性化合物的箭型固相微萃取结合气相色谱-质谱联用(SPME-Arrow/GC-MS)法。采用该方法对不同批次爆珠香精进行分析,结合主成分分析(PCA)、正交偏最小二乘-判别分析(OPLS-DA)及显著性F检验等多元统计分析手段,筛选显著性差异成分。结果表明:最佳萃取条件为优选DVB/CAR/PDMS萃取头,添加2.0 g氯化钠,在60℃下平衡50 min,萃取时间为40 min;经谱库检索结合保留指数辅助定性,共鉴定出96种挥发性、半挥发性组分,目标物峰面积的日间相对标准偏差(RSD)小于10%的色谱峰数量占总峰数量的92.7%,表明方法的重复性较好;从不同批次爆珠香精中共筛选出17个潜在差异化合物,通过显著性检验,确定10种显著性差异化合物,分别为α-蒎烯、柠檬烯、桉叶油醇、异胡薄荷醇、薄荷酮(含异构体)、新异薄荷醇、乙酸新薄荷酯、三辛酸甘油酯和二辛酸单癸酸甘油酯。该法可有效区分不同批次爆珠样品的组分差异,具有客观真实、准确可靠、可视化强等特点,能够为爆珠产品质量检验提供技术支持。

关键词：箭型固相微萃取气相色谱-质谱联用多元统计分析爆珠香精差异化合物

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Microstructure and mechanical property of Mg-10Gd-2Y-1.5Zn-0.5Zr alloy processed by eight-pass equal-channel angular pressing

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Rare Metals 2023年第4期42卷 1371-1377页

作者： huan Liu Jia ju Xiao-Wei Yang Yu-hua Li Jing-hua Jiang Ai-Bin Ma College of Mechanics and Materials Hohai UniversityNanjing211100China Suqian Research Institute of Hohai University Suqian223800China College of Materials Engineering Nanjing Institute of TechnologyNanjing211167China

In this work,a high-strength Mg-10Gd-2Y-1.5Zn-0.5Zr(wt%)alloy was prepared via eight passes of equal-channel angular pressing(ECAP).The microstructures and mechanical properties of as-cast and ECAP alloys were systematically investigated by X-ray diffraction(XRD),optical microscopy(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and electronic universal testing *** obtained results indicate that the microstructure of as-cast alloy consists ofα-Mg dendrite,network Mg3(Gd,Y,Zn)phase and lamellar 14H long-period stacking ordered(LPSO)phase which is precipitated near the boundary of Mg3(Gd,Y,Zn)*** eight-pass ECAP,the network Mg3(Gd,Y,Zn)phase is deformed and ***,the refined Mg_3(Gd,Y,Zn)particles are not distributed uniformly in the matrix,but still aggregated at the interdendritic ***,the content of 14H lamellas increases obviously,and they become bent and kinked during severe *** is activated in the region between Mg3(Gd,Y,Zn)particles and 14H *** test at room temperature indicates that the ECAP alloy exhibits excellent mechanical property with compressive strength of 518 MPa and fracture strain of 21.6%.The comprehensive high strength and toughness could be ascribed to the refined Mg_3(Gd,Y,Zn)particles,DRX grains and kinked 14H LPSO phase.

关键词： Mg-Gd-Y-Zn-Zr Long-period stacking ordered phase Equal-channel angular pressing Compression strength Fracture strain

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Entropic uncertainty relation of a qubit–qutrit Heisenberg spin model and its steering

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Communications in Theoretical Physics 2020年第12期72卷 123-129页

作者： Feng-He ju Zuo-yuan Zhang Jin-Ming Liu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

We investigate the quantum-memory-assisted entropic uncertainty relation(QMA-EUR)in a Heisenberg XYZ mixed-spin(1/2,1)*** strength,Dzyaloshinskii–Moriya(DM)interaction and inhomogeneous magnetic field,respectively,contributing to QMA-EUR by a thermal entanglement in the hybrid-spin model are studied in ***,we compare the uncertainty of the bipartite hybrid model with those of qubit–qubit and qutrit–qutrit ***,the effects of local PT-symmetric operation and weak measurement on the steering of entropic uncertainty are *** find that the local PT-symmetric operation can reduce the entropic uncertainty,and the entropic uncertainty can also be decreased by weak measurement reversal.

关键词： entropic uncertainty relation Heisenberg XYZ model weak measurement PT-symmetry

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