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Two-proton radioactivity of the excited state within the Gamow-like and modified Gamow-like models

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Nuclear Science and Techniques 2022年第10期33卷 1-10页

作者： De-xing Zhu Yang-Yang Xu Hong-Ming Liu xi-Jun wu Biao He xiao-Hua Li School of Nuclear Science and Technology University of South ChinaHengyang 421001China Institute of Modern Physics Fudan UniversityShanghai 200433China School of Math and Physics University of South ChinaHengyang 421001China College of Physics and Electronics Central South UniversityChangsha 410083China National Exemplary Base for International Sci&Tech.Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology&Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

In this study,we systematically investigated the two-proton(2p)radioactivity half-lives from the excited state of nuclei near the proton drip line within the Gamowlike model(GLM)and modified Gamow-like model(MGLM).The calculated results were highly consistent with the theoretical values obtained using the unified fission model[***.C 45,124105(2021)],effective liquid drop model,and generalized liquid drop model[Acta *** 71,062301(2022)].Furthermore,utilizing the GLM and MGLM,we predicted the 2p radioactivity halflives from the excited state for some nuclei that are not yet available ***,by analyzing the calculated results from these theoretical models,it was found that the half-lives are strongly dependent on Qand l.

关键词： 2p radioactivity Gamow-like model Halflife Excited state

Current Reversal in a Flashing Correlation Ratchet

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Chinese Physics Letters 1999年第7期16卷 475-477页

作者： ZHAO Tong-jun ZHAN Yong ZHUO Yi-zhong wu xi-zhen Department of Applied Mathematics and Physics Hebei University of Technology Tianjin 300130 China Institute of Atomic Energy Beijing 102413 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

A flashing correlation ratchet model is proposed,in which the transport of Brownian particles driven by additive colored noise of Ornstein-Uhlenbeck type in a flashing ratchet is studied by Monte Carlo *** stationary current vs the noise strength and the correlation time is obtained and *** a fixed rate of potential flashing,the novel phenomena of current reversal and reentry *** conditions for the occurrence of these phenomena are *** in fluence of the flipping rate is also *** finding might be relevant to the fact that the protein motors with similar structure can move in opposite directions on the same kind of microtubule.

关键词： directions noise Flash

Bi(OTf)3-catalyzed tandem reaction of naphthols with β,γ-unsaturated *** synthesis of functionalized 4H-chromenes

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Chinese Chemical Letters 2014年第9期25卷 1235-1239页

作者： Hui-Jing Li Dong-Hui Luo Qin-xi wu Chun-Yang Dai Zhi-Lun Shen Yan-Chao wu School of Marine Science and Technology Harbin Institute of Technology at Weihai Beijing National Laboratory for Molecular Sciences (BNLMS) and Key Laboratory of Molecular Recognition and FunctionInstitute of Chemistry Chinese Academy of Sciences

An efficient synthesis of functionalized 4H-chromenes by the tandem reaction of β,γ-unsaturated α- ketoesters with 2-naphthols, 1 -naphthols, and 1,3-dihydroxynaphthalenes has been accomplished with high selectivity and excellent yields in the presence of a catalytic amount of bismuth triflate [Bi（OTf）3, 5 mol%] under mild conditions. The functionalized 4H-chromene synthesis and our previous 2H- chromene hemiacetal synthesis could complement each other to enrich reaction diversity.

关键词： Bismuth triflate 4H-Chromenes Tandem reaction Selective synthesis

Detection of ryanodine receptor target-site mutations in diamide insecticide-resistant Spodoptera frugiperda in China

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Insect Science 2021年第3期28卷 639-648页

作者： Sheng-Lan Lv Yang Shi Jia-Cheng Zhang Pei Liang Lei Zhang xi-wu Gao College of Plant Protection China Agricultural UniversityBeijingChina

Spodoptera frugiperda(Lepidoptera:Noctuidae)is a widely distributed pest of *** it invaded China in 2018,it has caused serious damage to local corn ***,an anthranilic diamide insecticide,has been widely used to control lepidopteran *** is a new allosteric modulator insecticide devel-oped based on chlorantraniliprole,so it has a similar mechanism and insecticidal *** this study,we investigated resistance levels to chlorantraniliprole and tetrachloropyramid in *** from 13 populations in *** the populations tested,the relative highest resistance to chlorantraniliprole occurred in the Guangzhou population,and the most susceptible to chlorantraniliprole was found in the wuhan *** lethal dosage LD50 value of the Guangzhou population against chlorantraniliprole was 27.8-fold higher than that of the wuhan *** differences were observed among 5".frugiperda populations in terms of sensitivity to *** mutations at the 14734 site of the ryanodine receptor(RyR)were found,while no mutations were found in the G4891 *** mutations were detected in only two of the 786 individuals analyzed one from the Qinzhou population and other from the Anshun population(frequency below 2%in both cases).There were no significant differences in the expression levels of RyR between Guangzhou and wuhan *** summary,our results indicate that:(i)*** has low resistance levels to diamide insecticides in China;and(ii)the differences in relative resistance among the 13 populations analyzed are not caused by the mutations in RyR or the expression of RyR.

关键词： diamide insecticides resistance resistance risk Spodoptera frugiperda

Effects of 60-day NO_2 fumigation on growth,oxidative stress and antioxidative response in Cinnamomum camphora seedlings

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第3期11卷 190-199页

作者： Zhuo-mei CHEN Ying-xu CHEN Guo-jian DU xi-lin wu Feng LI College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China Zhejiang Forestry Academy Hangzhou 310023 China Department of Geography Minjiang University Fuzhou 350108 China

Objective： To study the oxidative stress and antioxidative response of Cinnamomum camphora seedlings exposed to nitrogen dioxide （NO2） fumigation. Methods： Measurements were made up of the growth, chlorophyll content, chlorophyll fluorescence, antioxidant system and lipid peroxidation of one-year-old C. camphora seedlings exposed to NO2 （0.1, 0.5, and 4 μl/L） fumigation in open top chambers over a period of 60 d. Results： After the first 30 d, 0.5 and 4.0 μl/L NO2 showed insignificant effects on the growth of C. camphora seedlings. However, exposure to 0.5 and 4.0 pilL NO2 for 15 d significantly reduced their chlorophyll content （P〈0.05）, enhanced their malondialdehyde （MDA） content and superoxide dismutase （SOD） activity （P〈0.05）, and also significantly reduced the maximal quantum yield of PSII in the dark [the ratio of variable fluorescence to maximal fluorescence （Fv/Fm）] （P〈0.05）. In the latter 30 d, 0.5μl/L NO2 showed a positive effect on the vitality of the seedlings, which was reflected by a recovery in the ratio of Fv/Fm and chlorophyll content, and obviously enhanced growth, SOD activity, ascorbate （AsA） content and glutathione reductase （GR） activity （P〈0.05）; 4.0 pilL NO2 then showed a negative effect, indicated by significant reductions in chlorophyll content and the ratio of Fv/Fm, and inhibited growth （P〈0.05）. Conclusion： The results suggest adaptation of C. camphora seedlings to 60-d exposure to 0.1 and 0.5 μl/L NO2, but not to 60-d exposure to 4.0 pilL NO2 C. camphora seedlings may protect themselves from injury by strengthening their antioxidant system in response to NO2-induced oxidative stress.

关键词： Cinnamomum camphora Fumigation Growth Chlorophyll content Chlorophyll fluorescence Antioxidant Lipid peroxidation

Gene Cloning and Tissue-Specific Expression of G Protein β Subunit in Microplitis mediator (Hymenoptera: Braconidae)

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Agricultural Sciences in China 2010年第4期9卷 568-576页

作者： ZHANG Shuai ZHANG Yong-jun CUI Jin-jie GAO xi-wu GUO Yu-yuan State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China Cotton Research Institute Chinese Academy of Agricultural Sciences Anyang 455000 P.R.China College of Agriculture and Biotechnology China Agricultural University Beijing 100193 P.R.China

A gene encoding a novel G protein β subunit of β1 subclass, GβMmed was isolated from Microplitis mediator （Hymenoptera： Braconidae）. The full-length sequence of GβMmed is 1 119 bp, the cDNA contains a 1 023 bp open reading frame that encodes a protein with 340 amino acids, and the predicted molecular weight of GβMmed is 37.23 kDa and isoelectric point is 5.86. By the quantitative real-time RT-PCR method, the tissue-specific expression and quantitative changes in the developmental expression profile of GβMmed were detected. It was found that GβMmed was abundantly expressed in M. mediator antennae, head （without antennae）, thorax, abdomen, legs and the wings, and especially at high levels in abdomen. In antennae, expression varied through 1st day before emergence to 5-d-old adults, and had equal expression levels detected in females and males in total. In head, GβMmed expresses while initially high in females, and have another peaked in stage 4 and 1st day, in males showed a peak of GβMmed expression prior to emergence and relatively low levels after emergence. In female abdomen GβMmed expression levels have two peaks in stage 1 and the 5th d, but just have one peak in male abdomen in stage 1. In all other tissues expression was low and stable.

关键词： Microplitis mediator G protein β subunit quantitative real-time RT-PCR expression pattern

A sublethal concentration of afidopyropen suppresses the population growth of the cotton aphid, Aphis gossypii Glover(Hemiptera: Aphididae)

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Journal of Integrative Agriculture 2022年第7期21卷 2055-2064页

作者： MA Kang-sheng TANG Qiu-ling LIANG Ping-zhuo LI Jian-hong GAO xi-wu Department of Entomology China Agricultural UniversityBeijing 100193P.R.China Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

The cotton aphid,Aphis gossypii Glover(Hemiptera:Aphididae),is an important insect pest of cotton crops *** objectives of this study were to determine the acute toxicity of afidopyropen and whether there are any effects of sublethal concentrations of afidopyropen on the biological characteristics of *** results showed that afidopyropen possesses high acute toxicity to adult *** with a 72 h LC_(50) value of 1.062 mg L^(–1).A sublethal concentration(LC_(10))of afidopyropen significantly decreased adult longevity,fecundity and oviposition days of female adults in both F0 and F1 *** total pre-adult survival of F_(1) progeny was also significantly reduced by 30%at the LC_(10) of *** addition,the nymph developmental time,pre-adult period,adult pre-reproductive period(APRP),and total pre-reproductive period(TPRP)of the F1 progeny were significantly prolonged compared with the *** population parameters,including the net reproductive rate(R_(0)),intrinsic rate of increase(r)and finite rate of increase(λ)of F_(1) progeny were significantly decreased by a sublethal afidopyropen concentration *** results indicated that sublethal concentration of afidopyropen can significantly suppress *** population *** would be useful for assessing the overall effects of afidopyropen on ***.

关键词： afidopyropen Aphis gossypii sublethal effects longevity fecundity

Tissue Segmentation in Nasopharyngeal CT Images Using Two-Stage Learning

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Computers, Materials & Continua 2020年第11期65卷 1771-1780页

作者： Yong Luo xiaojie Li Chao Luo Feng Wang xi wu Imran Mumtaz Cheng Yi West China Hospital Sichuan UniversityChengdu610000China Chengdu University of Information Technology Chengdu610000China University of Agriculture Faisalabad38000Pakistan

Tissue segmentation is a fundamental and important task in nasopharyngeal images ***,it is a challenging task to accurately and quickly segment various tissues in the nasopharynx region due to the small difference in gray value between tissues in the nasopharyngeal image and the complexity of the tissue *** this paper,we propose a novel tissue segmentation approach based on a two-stage learning framework and *** the proposed methodology,the network consists of two segmentation *** first module performs rough segmentation and the second module performs accurate *** the training time and the limitation of computing resources,the structure of the second module is simpler and the number of network layers is *** addition,our segmentation module is based on U-Net and incorporates a skip structure,which can make full use of the original features of the data and avoid feature *** evaluated our proposed method on the nasopharyngeal dataset provided by West China Hospital of Sichuan *** experimental results show that the proposed method is superior to many standard segmentation structures and the recently proposed nasopharyngeal tissue segmentation method,and can be easily generalized across different tissue types in various organs.

关键词： Tissue segmentation deep learning two-stage network convolutional neural network

Development of an Ultrasonic Nomogram for Preoperative Prediction of Castleman Disease Pathological Type

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Computers, Materials & Continua 2019年第7期61卷 141-154页

作者： xinfang Wang Lianqing Hong xi wu Jia He Ting Wang Hongbo Li Shaoling Liu Ultrasound Department of Nanjing Integrated Traditional Chinese and Western Medicine Hospital Affiliated with Nanjing University of Chinese Medicine Nanjing210014China Pathology Department of Nanjing Integrated Traditional Chinese and Western Medicine Hospital Affiliated with Nanjing University of Chinese Medicine Nanjing210014China Department of Computer Science Chengdu University of Information TechnologyChengdu610225China Vanderbilt University Institute of Imaging Science NashvilleTN37232USA Ultrasound Department of Affiliated Hospital of Nanjing University of Chinese Medicine Nanjing210029China Ultrasound Department of Shandong Provincial Medical Imaging Research Institute Jinan250021China

An ultrasonic nomogram was developed for preoperative prediction of Castleman disease(CD)pathological type(hyaline vascular(HV)or plasma cell(PC)variant)to improve the understanding and diagnostic accuracy of ultrasound for this *** cases of CD confirmed by pathology were gathered from January 2012 to October 2018 from three hospitals.A grayscale ultrasound image of each patient was collected and ***,the region of interest of each gray ultrasound image was manually segmented using a process that was guided and calibrated by radiologists who have been engaged in imaging diagnosis for more than 5 *** addition,the clinical characteristics and other ultrasonic features extracted from the color Doppler and spectral Doppler ultrasound images were also ***,the chi-square test was used to select and reduce ***,a naïve Bayesian model was used as a ***,clinical cases with gray ultrasound image datasets from the hospital were used to test the performance of our proposed *** these patients,31 patients(18 patients with HV and 13 patients with PC)were used to build a training set for the predictive model and 19(11 patients with HV and 8 patients with PC)were used for the test *** the set,584 high-throughput and quantitative image features,such as mass shape size,intensity,texture characteristics,and wavelet characteristics,were extracted,and then 152 images features were *** the radiomics classification results with the pathological results,the accuracy rate,sensitivity,and specificity were 84.2%,90.1%,and 87.5%,*** experimental results show that radiomics was valuable for the differentiation of CD pathological type.

关键词： Radiomics ultrasonic nomogram Castleman disease Bayesian feature extraction