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Root-fed Salicylic Acid in Grape Involves the Response Caused by Aboveground High Temperature

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Journal of Integrative Plant Biology 2008年第6期50卷 761-767页

作者： hong-tao liu Yue-Ping liu Wei-Dong Huang College of Food Science &Nutntional Engineenng China Agncultural University Beijing 100083 China Department of Biotechnology Beijing Agricultural College Beijing 102206 China

In order to investigate the transportation and distribution of salicylic acid （SA） from root to aboveground tissues in response to high temperature, the roots of grape plant were fed with 14C-SA before high temperature treatment. Radioactivity results showed that progressive increase in SA transportation from root to aboveground as compared with the control varied exactly with the heat treatment time. Radioactivity results of leaves at different stem heights indicated that the increase in SA amount at the top and middle leaves during the early period was most significant in comparison with the bottom leaves. The up-transportation of SA from root to aboveground tissues was dependent on xylem rather than phloem. Autoradiographs of whole grape plants strongly approved the conclusions drawn above. Root-derived SA was believed to be a fundamental source in response to aboveground high temperature.

关键词： aboveground grape high temperature root salicylic acid

A path planning algorithm for a crop monitoring fixed-wing unmanned aerial system

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Science China(Information Sciences) 2024年第8期67卷 5-23页

作者： Longhao QIAN Yi Lok LO Hugh hong-tao liu Institute of Aerospace Studies University of Toronto Department of Mechanical Engineering The University of Hong Kong

With the growing demand for automation in agriculture, industries increasingly rely on drones to perform crop monitoring and surveillance. In this regard, fixed-wing unmanned aerial systems(UASs)are viable platforms for scanning a large crop field, given their payload capacity and range. To achieve maximum coverage without landing for battery replacement, an algorithm for producing a minimal required energy survey path is essential. Hence, an energy-aware coverage path planning algorithm is proposed *** constraints for a fixed-wing UAS to fly at low altitudes while achieving full coverage of the crop field are first analyzed. Then, the full path is decomposed into straight-line and U-turn primitives. Finally, an algorithm to calculate a combination of straight-line segments and U-turns is proposed to obtain the path with minimum required energy consumption. The genetic algorithm is used to efficiently determine the order of the straight-line paths to traverse. Case studies show that the proposed algorithm can produce planning results for a convex-polygon-shaped crop field.

关键词： path planning genetic algorithm energy minimization fixed-wing UAS aerial survey

Effect of silencing Bcl-2 expression by small interfering RNA on radiosensitivity of gastric cancer BGC823 cells

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Asian Pacific Journal of Tropical Medicine 2013年第1期6卷 49-52页

作者： hong-tao liu Chun-Lei Lu Department of General Surgery Zhengzhou People's Hospital Department of Gastrointestinal Surgery Liberation Army 101 Hospital

Objective:To explore the influence of silencing Bcl-2 expression by small interfering RNA（siRNA） on Bcl-2 protein expression,cell apoptosis rale and radiosensilivity of gastric cancer BCC823 ***:siRNA segment for Bcl-2 gene was designed and synthesized,then was induced into gastric cancer BGC 823 cells by liposome ***-2 protein expression was detected by Western *** X radiation,flow cytometry and clone forming assay were used to determine the effects of RNA interference on BGC823 cell apoptosis rate and radiosensitivity. Result:After the transfection of Bcl-2 siRNA,the positive expression rate of Bcl-2 protein in BGC823 cells was（35.45±2.35）%.Compared with the control group and negative siRNA transfection group,the rate was significantly decreased（P0,D4 and SF2 values in Bcl-2 siRNA1 transfection group were all lower than those in the control *** radiosensitivity ratio was 1.28（the ratio of D0） and 1.60（the ratio of D4）.Conclusions:Specific siRNA of Bcl-2 gene can effectively inhibit the expression of Bcl-2 gene,enhance the radiosensitivity and apoptosis of gastric cancer BGC823 cells,having good clinical application perspective.

关键词： Gastric cancer BGC823 cell Bcl-2 Radiosensitization RNA interference

Theoretical analyses of chemical bonding in terminal EThF_2 (E=O,S,Se,Te)

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Nuclear Science and Techniques 2019年第5期30卷 1-8页

作者： Yan-Li Li Xiao-Gen Xiong hong-tao liu Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen University

Analyses of chemical bonding and geometric structures in species with chalcogen elements EThF_2(E=O,S,Se,Te) are performed by the density functional theory. Kohn–Sham molecular orbitals and Th–E bond lengths of these species both indicate multiple bond character for the terminal chalcogen complexes. This is also confirmed by natural bond orbital analyses using the oneelectron density matrix generated by relativistic density functional calculations. Theoretical analyses indicate that electron donation from E to Th increases down the chalcogen group(O

关键词： EThF2 Chemical bonding Natural bond orbital (NBO)

Possible γ-ray emission of radio intermediate AGN Ⅲ Zw 2 and its implication on the evolution of jets in AGNs

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Research in Astronomy and Astrophysics 2010年第8期10卷 707-712页

作者： Liang Chen Jin-Ming Bai Jin Zhang hong-tao liu National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Physics and Electronic Engineering Guangxi Teachers Education University Nanning 530001 China

AGNs with hard γ-ray emission identified so far are radio-loud. Ⅲ Zw 2 is a radio intermediate AGN with a relativistic jet. We study its spectral energy distribution （SED） and find that the broad band emissions are dominated by the nonthermal emissions from the jet. We model its SED through a synchrotron ＋ inverse Compton （IC） model. The results show that the IC component of Ⅲ Zw 2 peaks at a few MeV, and the flux density drops rapidly at higher energy with photon index F 3.3 above 0.1 GeV. The predicted flux is slightly over the sensitivity of Fermi/LAT, but it was not included in the first Fermi/LAT AGN catalog. The reason for this may be： 1） that the IC peak is low and the spectrum is very steep above 0.1 GeV, 2） that Ⅲ Zw 2 is in the low state during the period of the Fermi/LAT operation. We also find that Ⅲ Zw 2 follows similar jet processes as those in γ-ray AGNs, e.g., the relation between jet power and radiation power, which is called the blazar sequence. We suggest that Ⅲ Zw 2 may be a young source at an earlier stage of jet activity.

关键词： galaxies active -- galaxies Seyfert- galaxies jets -- radiation mechanisms non-thermal

Jasmonic Acid is Induced in a Biphasic Manner in Response of Pea Seedlings to Wounding

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Journal of Integrative Plant Biology 2009年第6期51卷 562-573页

作者： Hao-Ru Yang Ke Tang hong-tao liu Qiu-hong Pan Wei-Dong Huang College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China Institute of Geographic Sciences and Natural Resources Research the Chinese Academy of Sciences Beijing 100101 China

The role of jasmonic acid （JA） in plant wounding response has been demonstrated. However, the source of JA in wound signaling remains unclear. In the present study, pea seedlings were used as material to investigate the systemic induction of JA and the activation of lipoxygenase （LOX）-dependent octadecanoid pathway upon wounding. The results showed that endogenous JA could induce two peaks in the wounded leaves and the stalks, while only one peak in the systemic leaves. LOX activity and its protein amount were also induced and the stimulation mainly occurred in the late phase, while one peak of induction was present after pretreatment with JA. Applied nordihydroguaiaretic acid （NDGA）, an inhibitor of LOX activity, only inhibited the induction of JA in the late phase, and the resistance of pea was impaired. Furthermore, 13（S）- hydroperoxy-9（Z）, 11 （E）-octadecadienoic acid （13（S）-H（P）ODE） was confirmed to be the main product of LOX throughout the experimental time. in addition, immunocytochemical analysis also revealed the occurrence of JA biosynthesis and transport upon wounding. These results demonstrated that wound-induced JA in wounded leaves resulted from its biosynthesis and conversion from its conjugates, while in systemic leaves resulted from its transport and biosynthesis; and proved that the LOX pathway was vital to the wound-induced defense response involved in JA biosynthesis.

关键词： defense response jasmonic acid lipoxygenase pea (Pisum sativum L.).

One-pot Synthesis of Lewis Acidic Ionic Liquids for Friedel-Crafts Alkylation

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Chinese Chemical Letters 2006年第3期17卷 321-324页

作者： Ling HE Guo hong tao Wei Shan liu Wei XIONG tao WANG Yuan KOU Green Chemistry Centre College of Chemistry and Molecular Engineering State Key Laboratory for Structural Chemistry of Unstable and Stable Species Peking University Beijing 100871

Novel Lewis acidic ionic liquids containing thionyl cations and chloroaluminate anions were obtained by one-pot synthesis for the first time. Their acidities were determined by acetonitrile probe on IR spectrography. The ionic liquids were used as catalyst for Friedel-Crafts alkylation of benzene and 1-dodecene. The turnovers of l-dodecene were higher than 99%. Monoalkylbenzene selectivity was 98%, while the 2-substituent product selectivity was 45%.

关键词： Ionic liquids green chemistry one-pot synthesis Lewis acidity alkylation.

Statistical Properties of a Blazar Sample and Comparison of HBLs, LBLs and FSRQs

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 471-486页

作者： Li-Sheng Mao Guang-Zhong Xie Jin-Ming Bai hong-tao liu Yunnan Observatory National Astronomical Observatories Chinese Academy of SciencesKunming 650011 Graduate University of Chinese Academy of Sciences Beijing 100049 Yunnan Astrophysics Center Yunnan University Kunming 650091

Making use of the 2MASS Data Release, we have searched for nearinfrared （JHK） counterparts to 268 blazars from Donato et al. and obtained 238 counterparts within 5＇＇ in the area covered by 2MASS. It provides us a sample with infrared data several times larger than the previous one of the same kind. Based on our sample and the sample by Donato et al., we have compared in detail the properties of HBLs, LBLs and FSRQs from five aspects and found that HBLs are significantly different from LBLs and FSRQs while LBLs are not obviously different from FSRQs. Our results strongly support the division of BL Lac objects into the high-frequency peaked （HBL） and low-frequency peaked （LBL） objects introduced by Padovani ＆ Giommi and show that HBLs and LBLs are two kinds of blazar having different physical properties.

关键词： BL Lacertae objects: general-infrared: galaxies - methods: statistical

Value of mink vomit model in study of anti-emetic drugs

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World Journal of Gastroenterology 2006年第8期12卷 1300-1302页

作者： Fang Zhang Lei Wang Zhi-hong Yang Zhan-tao liu Wang Yue Department of Pharmacology Medical College of Qingdao University Qingdao 266021 Shandong Province China

AIM： To establish a new, reliable vomit model of minks METHODS： Adult male minks were randomly divided into 8 groups （n=6）： cisplatin （7.5 mg/kg） intraperitoneal injection （ip） group, copper sulfate （40 mg/kg） intragastric injection （ig） group, apomorphine （1.6 mg/kg） subcutaneous injection （sc） group, and 18 Gy whole-body X-irradiation group, ondansetron injection group （2 mg/kg ip） 30 min later followed by cisplatin （7.5 mg/kg） ip, normal saline （NS） ip injection control group, metoclopramide injection group （4 mg/kg ip） 30 rain later followed by apomorphine （1.6 mg/kg） sc, NS ig control group. The frequency of retching and vomiting was calculated. After behavioral experiment, distribution of 5-HT in the ileum was detected by immunohistologic method. RESULTS： Cisplatin, apomorphine, copper sulfate and X-irradiation administered to minks evoked a profound emetic response in the animals. However, retching and vomiting were significantly inhibited by pretreatment with ondansetron and metoclopramide in cisplatin and copper sulfate groups （P=0.018）. Immunohistologic result showed that 5-HT released from enterochromaffin cells （EC cells） was involved in vomiting mechanism. CONCLUSION： Mink vomit model has a great value in studying the vomiting mechanism and screening new antiemetic drugs.

关键词： Vomit Mink Cisplatin Ondansetron Apomorphine X-irradiation