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Evaluation of five antibiotics on larval gut bacterial diversity of Plutella xylostella （Lepidoptera： Plutellidae）

Insect Science 2015年第5期22卷 619-628页

作者： Xiao-Li Lin zhi-Wei Kang qin-Jian Pan Tong-Xian Liu State Key Laboratory of Crop Stress Biology in Arid Areas and Key Laboratory of Northwest Loess Plateau Crop Pest Managementof Ministry of Agriculture Northwest A&F University Yangling Shaanxi 712100 China

Larvae of the diamondback moth, Plutella xylostella L. （Lepidoptera： Plutelli- dae）, have rich microbial communities inhabiting the gut, and these bacteria contribute to the fitness of the pest. In this study we evaluated the effects of five antibiotics （rifampicin, ampicillin, tetracycline, streptomycin sulfate and chloramphenicol） on the gut bacterial di- versity ofP xylostella larvae. We screened five different concentrations for each antibiotic in a leaf disc assay, and found that rifampicin and streptomycin sulfate at 3 mg/mL signif- icantly reduced the diversity of the bacterial community, and some bacterial species could be rapidly eliminated. The number of gut bacteria in the rifampicin group and strepto- mycin sulfate group decreased more rapidly than the others. With the increase of antibiotic concentration, the removal efficiency was improved, whereas toxic effects became more apparent. All antibiotics reduced larval growth and development, and eventually caused high mortality, malformation of the prepupae, and hindered pupation and adult emergence. Among the five antibiotics, tetracycline was the most toxic and streptomycin sulfate was a relatively mild one. Some dominant bacteria were not affected by feeding antibiotics alone. Denaturing gradient gel electrophoresis graph showed that the most abundant and diverse bacteria in P xylostella larval gut appeared in the cabbage feeding group, and diet change and antibiotics intake influenced gut flora abundance. Species diversity was significantly reduced in the artificial diet and antibiotics treatment groups. After feeding on the artificial diet with rifampicin, streptomycin sulfate and their mixture for 10 days, larval gut bacteria could not be completely removed as detected with the agarose gel electrophoresis method.

关键词： antibiotics endosymbiont gut bacteria microbes PCR-DGGE

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A method to evaluate the bioactive function of fruit extracts of Chinese wild Citrus with microtubular activity

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Journal of Integrative Agriculture 2017年第4期16卷 867-873页

作者： GUAN Xin TAN Si Günther Buchholz Peter Nick ZHOU zhi-qin College of Horticulture and Landscape Architecture Southwest University Chongqing 400716 P.R. China Molecular Cell Biology Botanical Institute Karlsruhe Institute of Technology Karlsruhe D-76128 Germany RLP AgroScience/AIPlanta-institute for Plant Research Neustadt an der Weinstrasse D-67435 Germany Laboratoire Vigne Biotechnologies et Environnement EA-3991 Universit6 de Haute-Alsace Colmar 68000 France Key Laboratory of Horticulture Science for Southern Mountainous Regions Ministry of Education Chongqing 400716 P.R. China

China is one of the most important centers of origin for Citrus genetic resources. Due to the high content of secondary metabolites, mining wild Chinese Citrus for novel medical applications is promising. In this study, extracts of Chinese wild species from different taxonomical groups were screened for potential effects on microtubules （MTs） in vitro. MT density as a readout for nucleation, and frequency distribution over MT lengths as a readout for elongation and decay were determined by quantitative image analysis via a standardized coverslJp assay using fluorescently labelled neurotubulin. Extract from peels of Citrus ichangensis Swing. strongly increased the density of MTs; whereas, extract from peels of Cfurs limon （L.） Burm.f. exerted the opposite effect. Extract from pulp of Citrus limonia Osbeck promoted MT elongation, and in addition induced a small population of very long MTs. These data suggest that wild Chinese Citrus harbour compounds that act specifically on different aspects of MT nucleation, elongation, and decay.

关键词： fruit extract natural product-based pharmaceuticals Chinese wild Citrus microtubules secondary plant metabolites

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An approach to extracting surface supply relationships between glaciers and lakes on the Tibetan Plateau

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International Journal of Digital Earth 2018年第11期11卷 1151-1165页

作者： Bei-Bei Ai Cheng-zhi qin qinghua Ye A-Xing Zhu Graham Cogley State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijingPeople’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijingPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application and School of Geography Nanjing Normal UniversityNanjingPeople’s Republic of China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchCASBeijingPeople’s Republic of China Department of Geography University of Wisconsin-MadisonMadisonWIUSA Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjingPeople’s Republic of China Department of Geography Trent University PeterboroughCanada

Surface supply relationships between glaciers and lakes are needed to analyze and understand hydrological processes at regional and global ***,these supply relationships still cannot be extracted efficiently by existing *** paper proposes an automatic and efficient approach to extracting surface supply relationships between glaciers and lakes based on meltwater flow *** approach includes two stages:(1)identifying direct connections between objects(*** and lakes)based on flow direction derived from digital terrain analysis on a gridded digital elevation model(DEM)and(2)deriving all(or user-specified)kinds of surface supply relationships based on graph *** computation-intensive steps in this approach have been parallelized;and all steps in the proposed approach have been integrated as an automatic *** for the Tibetan Plateau show that given outline data for glaciers and lakes and the Shuttle Radar Topography Mission DEM,the proposed approach can automatically derive diverse surface supply relationships under userspecified restrictions on the attributes of the supply *** parallelization in the approach effectively improves the computing *** proposed approach could also be applied to developing a detailed fundamental dataset of supply relationships between glaciers and lakes for other region or period.

关键词： Glaciers and lakes surface supply relationship digital terrain analysis parallel computing Tibetan Plateau

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A Linear Frequency Principle Model to Understand the Absence of Overfitting in Neural Networks

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Chinese Physics Letters 2021年第3期38卷 121-126页

作者： Yaoyu Zhang Tao Luo Zheng Ma zhi-qin John Xu School of Mathematical Sciences Institute of Natural SciencesMOE-LSCand Qing Yuan Research InstituteShanghai Jiao Tong UniversityShanghai 200240China Shanghai Center for Brain Science and Brain-Inspired Technology Shanghai 200031China

Why heavily parameterized neural networks(NNs) do not overfit the data is an important long standing open question. We propose a phenomenological model of the NN training to explain this non-overfitting puzzle. Our linear frequency principle(LFP) model accounts for a key dynamical feature of NNs: they learn low frequencies first, irrespective of microscopic details. Theory based on our LFP model shows that low frequency dominance of target functions is the key condition for the non-overfitting of NNs and is verified by experiments. Furthermore,through an ideal two-layer NN, we unravel how detailed microscopic NN training dynamics statistically gives rise to an LFP model with quantitative prediction power.

关键词： networks neural details

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Highly efficient regioselective ring openings of N-tosylaziridines to haloamines using ferric(Ⅲ) halides

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Chinese Chemical Letters 2014年第8期25卷 1174-1178页

作者： Xing Li zhi-qin Sun Hong-Hong Chang Wen-Long Wei Department of Chemistry and Chemical Engineering Taiyuan University of Technology

FeX3（X = Cl, Br） were found to be very effective reagents and powerful catalysts for regioselective ring openings of a variety of N-tosylaziridines with them to afford the corresponding b-haloamines in good to excellent yields with high regioselectivity under mild conditions. At the same time, 13 new compounds were obtained firstly. Moreover, the b-bromoamine prepared could be transferred into b-nitroamine with NaNO2 in moderate yield.

关键词： Ring-opening N-Tosylaziridine Haloamine Ferric (Ⅲ) halide Regioselectivity

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Selective De-O-acetylation in TCP-containing Carbohydrate Structures with Magnesium Methoxide

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Chinese Chemical Letters 2000年第11期11卷 941-944页

作者： qin, zhi Hui Li, Hui Cai, Meng Shen Li, Zhong Jun Department of Bioorganic Chemistry School of Pharmaceutical Sciences Beijing Medical University Beijing 100083 China

Magnesium methoxide can be used for TCP-containing substrates to remove acetyl group successfully while leaving the TCP- group virtually intact.

关键词： OCH TCP De

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GC/MS Analysis of Fractional Extraction of Fusain from Tongting Bituminous Coal in CS_2

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Journal of China University of Mining and Technology 2006年第1期16卷 8-12页

作者： qin zhi-hong JIANG Chun SUN Hao ZONG zhi-min JIANG Bing WEI Xian-yong School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FTTB coal and clarain from Tongting bituminous (CTTB) coal was carried out. The results show that the kinds of small molecule components detected by GC/MS of FTTB are less than those of CTTB. Long-chain alkanes exist mostly in the extracts of fusain. Macromolecular networks are predominant in the FTTB coal mainly composed of inertinite in the coal petrography. The size of micropores in the FTTB coal is relatively small, and the development of micropores is relatively low. Thus the content of aromatic compounds with affinity for micropores is relative low in FTTB, while the content of long-chain alkanes with affinity for macromolecule networks is relatively high. Sub-components in exinite determine the distribution of long-chain alkanes extracted in the last stage. Odd-numbered carbon distribution appears when resin is most in exinite, while high carbon alkane distribution appears when exinite is dominant in cutinite. Small aromatic molecules are firstly packed in micropores, and exist in a free state after micropores are saturated.

关键词： coal fusain extraction fractional sample CS2 GC/MS

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Computed tomography angiography-guided percutaneous coronary intervention in chronic total occlusion

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 568-574页

作者： Ping LI Lu-yue GAI Xia YANG zhi-jun SUN qin-hua JIN Department of Cardiology Chinese PLA General Hospital Beijing 100853 China

Objective： The aim of this study is to investigate if dual-source computed tomography （DSCT） could guide the percutaneous coronary intervention （PCI） of chronic total occlusion （CTO）. Methods： We enrolled patients who were confirmed to have at least one native coronary artery CTO by DSCT before they underwent selective PCI in the period from December 2007 to October 2008. A CTO was defined as an obstruction of a native coronary artery with no luminal continuity. The CT-guided PCI procedure involved placing CT and fluoroscopic images side-by-side on the screen. DSCT images were analyzed for location, segment, plaque characteristics, calcification, and proximal lumen diameter of the CTO before PCI. The guidewire was advanced and manipulated under CT guidance. The PCI was carried out and the results were compared. Results： Seventy-four CTOs were assessed. PCI was successful in 57 cases of CTOs （77.0%）. According to the results, CTOs were divided into two groups： successfuI-PCI and failed-PCI. All coronary artery paths of CTOs were clearly recognized by DSCT. In the successfuI-PCI group, soft plaques were detected much more often than those in the failed-PCI group, but fibrous and calcified plaques were seen more often in the failed-PCI group. Calcification severity in CTO segments showed a significant difference between the groups （P=0.014）. Calcified plaques were detected in 20 （35.1%） lesions in the successfuI-PCI group. More than 70% of the failures were calcified plaques, of which there were two arc-calcified and one circular-calcified lesions. Occlusions were longer in the failed-PCI group than those in the successfuI-PCI group [（38.8±25.0） vs. （18.0±15.3） mm, respec- tively, P〈0.01]. Fewer guidewires were used in the successfuI-PCI group compared with the failed-PCI group （1.7±1.0 vs. 2.5±0.9, respectively, P〈0.01）. The logistic regression analysis indicated that predictors of recanalization of CTOs included occlusion length （P=-0.0035, risk ratio （RR）=0.93） and

关键词： Dual-source computed tomography (DSCT) Chronic total occlusion (CTO) Angiography Recanalization

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A new forsythenside from Forsythia suspensa

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Chinese Chemical Letters 2008年第10期19卷 1234-1236页

作者： Yan zhi Wang qin Ge Ma Xiao Ke Zheng Wei Sheng Feng Henan College of Traditional Chinese Medicine Zhengzhou 450008 China

A new forsythenside, 4-hydroxy-4-[8-[[1-[（4-hydroxyphenyl）acetyl]-β-D-glucopyranosyl-6-]oxy]ethy1]-2,5-cyclohexadien-1- one, named forsythenside F, was isolasted from the plant of Forsythia suspensa （Thunb.） Vahl. The structure of the new compound was established on the basis of various spectroscopic analysis, including ^1H NMR, ^13C NMR, 2D NMR techniques （HMBC and HSQC）, and HR-ESI-MS.

关键词： Forsythia suspensa Forsythcnside Forsythcnside F

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Electromagnetic scattering and imaging simulation of extremely large-scale sea-ship scene based on GPU parallel technology

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Journal of Electronic Science and Technology 2024年第2期22卷 16-23页

作者： Cheng-Wei Zhang zhi-qin Zhao Wei Yang Li-Lai Zhou Hai-Yu Zhu Southwest China Institute of Electronic Technology Chengdu610036China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Tencent Company Shenzhen518054China

Aiming to solve the bottleneck problem of electromagnetic scattering simulation in the scenes of extremely large-scale seas and ships,a high-frequency method by using graphics processing unit(GPU)parallel acceleration technique is *** the implementation of different electromagnetic methods of physical optics(PO),shooting and bouncing ray(SBR),and physical theory of diffraction(PTD),a parallel computing scheme based on the CPU-GPU parallel computing scheme is realized to balance computing ***,a multi-GPU framework is further proposed to solve the computational difficulty caused by the massive number of ray tubes in the ray tracing *** using the established simulation platform,signals of ships at different seas are simulated and their images are achieved as *** is shown that the higher sea states degrade the averaged peak signal-to-noise ratio(PSNR)of radar image.

关键词： Multi graphics processing unit Radar imaging Sea-ship Shooting and bouncing rays

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