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Biosynthesis of artemisinic acid in engineered Saccharomyces cerevisiae and its attractiveness to the mirid bug Apolygus lucorum

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Journal of Integrative Agriculture 2022年第10期21卷 2984-2994页

作者： TENG Dong LIU dan-feng Khashaveh ADEL SUN Pei-yao GENG Ting zhang da-wei zhang Yong-jun State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunming 650091P.R.China Langfang Scientific Research Trial Station Institute of Plant ProtectionChinese Academy of Agricultural SciencesLangfang 065000P.R.China Institute of Plant Protection Gansu Academy of Agricultural SciencesLanzhou 730070P.R.China

Artemisia annua is an important preferred host of the mirid bug Apolygus lucorum in *** emitted from *** attract *** artemisinic acid of *** is a precursor of artemisinin that has been widely investigated in the Chinese herbal medicine ***,little is known at this point about the biological roles of artemisinic acid in regulating the behavioral trends of *** this study,we collected volatiles from *** at the seedling stage by using headspace solid phase microextraction(HS-SPME).Gas chromatography-mass spectrometry(GC-MS) analysis showed that approximately 11.03±6.00 and 238.25±121.67 ng hartemisinic acid were detected in volatile samples and milled samples,***,a key gene for artemisinic acid synthesis,the cytochrome P450 gene cyp71 av1,was expressed in engineered Saccharomyces cerevisiae to catalyze the production of artemisinic *** the addition of exogenous artemisinic alcohol or artemisinic aldehyde,artemisinic acid was identified as the product of the expressed *** electroantennogram(EAG) recordings,3-day-old adult *** showed significant electrophysiological responses to artemisinic alcohol,artemisinic aldehyde and artemisinic ***,3-day-old female bugs were significantly attracted by artemisinic acid and artemisinic alcohol at a concentration of 10 mmol L,whereas 3-day-old male bugs were attracted significantly by 10 mmol Lartemisinic acid and artemisinic *** propose that artemisinic acid and its precursors could be used as potential attractant components for the design of novel integrated pest management strategies to control ***.

关键词： artemisinic acid CYP71AV1 biosynthesis Apolygus lucorum electrophysiological responses behavioral trends

Synthesis and Characterization of a New Titanium-silicate Material Containing Cage-like Polyhedral Oligosilsesquioxane

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Chemical Research in Chinese Universities 2007年第4期23卷 388-390页

作者： DING Han-ming zhang da-wei LI Jiang KONG Ai-guo SHAN Yong-kui Department of Chemistry East China Normal University Shanghai 200062 P. R. China

A new titanium-silicate material was synthesized with cubic cage-like tetramethylammonium octasilicate and TiCl4 ethanol solution as precursors. The product was characterized by FTIR, ^29Si NMR, UV-Vis, and XRD. Struc-tural and ingrediental analyses suggest that this material has a layered structure with cubic cage-like polyhedral oligo-silsesquioxane as building blocks and titanium as bridging atoms.

关键词： Polyhedral oligosilsesquioxane Synthesis Titanium-silicate material

Genome-wide identification and expression analysis of anthocyanin biosynthetic genes in Brassica juncea

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Journal of Integrative Agriculture 2020年第5期19卷 1250-1260页

作者： zhang da-wei LIU Li-li ZHOU Ding-gang LIU Xian-jun LIU Zhong-song YAN Ming-li School of Life Science Hunan University of Science and TechnologyXiangtan 411201P.R.China Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization Xiangtan 411201P.R.China College of Life Sciences Resources and Environment SciencesYichun UniversityYichun 333600P.R.China Oilseed Research Institute Hunan Agricultural UniversityChangsha 410128P.R.China

Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.

关键词： anthocyanin biosynthetic genes B.juncea comparative genomic analysis transcriptome leaf color

Numerical study on forming complex fitting body on end of integrated stainless steel pipe without welds

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Journal of Central South University 2016年第2期23卷 269-276页

作者：张大伟赵升吨 School of Mechanical Engineering Xi'an Jiaotong University Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham

It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of preforming combined finish forming process is developed. The preforming process is characterized by flaring combined upsetting for left fitting body which is like a flange, and is characterized by tube axial compressive process under die constraint for right fitting body which is like a double-wall pipe. The finite element simulations of the processes are carried out by software package DEFORM, and the results indicate that: 1) left or right fitting body can be formed by a two-step forming process without folding and under-filling defects; 2) by using two-step forming, strain and stress in left fitting body are larger than those in right fitting body, and deformation in right fitting body is more homogenous than the deformation in left fitting body; 3) two or more preforming steps may be needed for left fitting body considering the distributions of strain and stress.

关键词： plastic forming hot forming flange joint integrated steel pipe finite element analysis

Javelin:an access and manipulation interface for large displays

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第11期11卷 893-902页

作者： Zhen-kun ZHOU Jiang-qin WU Yin zhang da-wei XIE Yue-ting ZHUANG School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

We describe a user interface and interaction technique,named'Javelin',designed for large display *** provides quick access to random screen regions and manipulation methods for screen widgets which are difficult or impossible to *** consists of a dynamic global thumbnail,a touchpad widget that drives the screen cursor,and a teleport widget in which interactions are transferred to its target screen *** can be easily integrated into many programs to optimize their interaction performance in large *** experiment and user study show that Javelin can extend user access field and enhance widget manipulation in large displays.

关键词： Large display User interface Interaction method Screen widget Remote target acquisition Human-computer interaction (HCI)

THE QIONGHAI CRUSTAL TILT OBSERVATION SYSTEM AND THE SEISMIC ACTIVITY IN WESTERN SICHUAN PROVINCE, CHINA

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地震地质 1990年第2期 115-120页

作者： zhang Chong-li, zhang Cun-de Xiang Jia-cui, Li Tie-ming and zhang da-wei(Institute of Geology, State Seismological Bureau)

In this paper, we introduce the measurements of crustal tilt using the Qionghai Observation System and a preliminary approach to the relation between the crustal plane tilt observed by the System and seismic activity in the region around the Qionghai Lake, at *** results show that the observed accuracy may reach the magnitude of 10-7-10-8 radian. The processes of the crustal stress accumulation and release are characterized by the activity of moderate earthquakes (M≥5.0) whose epicenters are located within a range away from the Qionghai Lake, and are reflected to a certain extent by time dependent processes of the crustal tilt observed by the *** short- term and impending precursors of moderate earthquakes are similar to those of the great ones, featuring of trending and abrupt anomalies.

关键词： Crustal deformation Xichang Qionghai Seismic activity

Meta-Analysis of 100-Seed weight QTLs in Soybean

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Agricultural Sciences in China 2011年第3期10卷 327-334页

作者： QI Zhao-ming SUN Ya-nan WANG Jia-lin zhang da-wei LIU Chun-yan HU Guo-hua CHEN Qing-shan Northeast Agricultural University Harbin 150030 P.R. China The Crop Research and Breeding Center of Land-Reclamation Harbin 150090 P.R.China

100-seed weight is a very complicated quantitative trait of yield. The study of gene mapping for yield trait in soybean is very important for application. However, the mapping result of 100-seed weight was dispersed, the public map should be chosen which was suitable for the published results integrated, and to improve yield. In this research, an integrated map of 100-seed weight QTLs in soybean had been established with soymap2 published in 2004 as a reference map. QTLs of 100-seed weight in soybean were collected in recent 20 yr. With the software BioMercator 2.1, QTLs from their own maps were projected to the reference map. From published papers, 65 QTLs of 100-seed weight were collected and 53 QTLs were integrated, including 17 reductive effect QTLs and 36 additive effect QTLs. 12 clusters of QTLs were found in the integrated map. A method of meta-analysis was used to narrow down the confidence interval, and 6 additive QTLs and 6 reductive QTLs and their corresponding markers were obtained respectively. The minimum confidence interval （C.I.） was shrunk to 1.52 cM. These results would lay the foundation for marker-assisted selection and mapping QTL precisely, as well as QTL gene cloning in soybean.

关键词： soybean 100-seed weight meta-analysis consensus QTL marker assisted selection

A long journey： report of a case with pancreatic abscess extending to the groin

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Chinese Medical Journal 2010年第22期123卷 3362-3363页

作者： LU Hui-min zhang Zhao-da HU wei-ming Department of Hepato-bilio-pancreatic surgery West China Hospital Sichuan University Chengdu Sichuan 610041 China

Acute pancreatitis is an inflammatory process with .variable involvement of regional tissue, remote organ systems, or both. Various complications of pancreatitis are common, including intra- or extrapancreatic fluid collections and development of a pancreatic pseudocyst or abscess, or even pancreatic tissue necrosis. Infected necrosis involves diffuse bacterial inflammation of necrotic pancreatic and peripancreatic tissue without significant pus collection. In contrast, a pancreatic abscess is a circumscribed collection of pus, usually in proximity to the pancreas, that is positive for bacteria, bounded by adjacent tissue and organs and has minimal amounts of associated necrosis.

关键词： pancreatic abscess groin

基于连接低干扰的无线Mesh网络信道分配算法研究

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电子科技大学学报 2014年第6期43卷 817-822页

作者：张伟昆黄炜张大伟 91872部队桂林电子科技大学电子工程与自动化学院

为合理地分配和利用无线信道资源,研究者们提出了许多关于多射频多信道无线Mesh网络的信道分配算法。该文针对无线Mesh网络的信道分配算法,以连接低干扰信道分配算法(CLICA)为基础,以提高网络容量(吞吐量)为目标提出了一种改进算法。该... 详细信息

为合理地分配和利用无线信道资源,研究者们提出了许多关于多射频多信道无线Mesh网络的信道分配算法。该文针对无线Mesh网络的信道分配算法,以连接低干扰信道分配算法(CLICA)为基础,以提高网络容量(吞吐量)为目标提出了一种改进算法。该算法根据网络中各链路的干扰度来计算网络干扰度,通过减小网络的干扰度来提高网络吞吐量,以实现最小化网络干扰度的目标。构建信道分配的数学优化模型,通过NS2仿真验证比较改进前后算法的性能,求解出最优的信道分配。

关键词：信道分配 CLICA算法网络模型无线Mesh网络