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Shoot Apex Demand Determines Assimilate and Nutrients Partitioning and Nutrient-uptake Rate in Tobacco Plants

Journal of Integrative Plant Biology 2007年第11期49卷 1654-1661页

作者： Huai-Yu Yang Chun-jian li fu-Suo Zhang The Key Laboratory of Plant Nutrition Ministry of Agriculture Key Laboratory of Plant-Soil Interactions Ministry of Education Department of Plant Nutrition China Agricultural University Beijing 100094 China

Our previous experiment revealed that apex-removed plants have larger root systems but a lower K＋-uptake rates than intact tobacco plants. Since the apex is not only a center of growth and metabolism, but also an important place of auxin synthesis and export, the aims of this study were to distinguish whether the apex demand or auxin synthesized in the apex regulates assimilate and nutrients partitioning within plant, and to explain the reason for the lower K＋-uptake rate of the apex-removed plant. In comparison with the control plant, covering the shoot apex with a black transparent plastic bag reduced net increases in dry matter and nutrients; however, the distribution of the dry matter and nutrients between shoot and roots and nutrient-uptake rates were not changed. Removal of the shoot apex shifted the dry mass and nutrients distributions to roots, and reduced the rate of nutrient uptake. Application of 1-naphthylacetic acid （NAA） could partly replace the role of the removed apex, stimulated assimilate and nutrient deposition into the treated tissue, and enhanced the reduced plasma membrane ATPase activity of roots to the control level. However, treatment of the apex-removed plants with NAA could not rescue the reduced nutrient uptake rate and the shifted assimilates and nutrients partitioning caused by excision of the apex. Higher nutrient uptake rate of the intact plants could not be explained by root growth parameters, such as total root surface area and number of root tips. The results from the present study indicate that strong apex demand determined assimilates and nutrients partitioning and nutrient-uptake rate in tobacco （Nicotiana tabacum） plants.

关键词： assimilate and nutrient partitioning auxin nutrient uptake removal of the shoot apex shoot apex demand tobacco (Nicotiana tabacum).

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AI-2 Key Enzyme S-Ribosylhomocysteinase from Strain Klebsiella pneumoniae CICC 10011 Producing 2,3-Butanediol

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Chemical Research in Chinese Universities 2011年第2期27卷 273-276页

作者： DAI jian-ying ZHANG li-fu XIU Zhi-long School of life Science and Biotechnology Dalian University of Technology Dalian 116024 P. R. China

S-Ribosylhomocysteinase（LuxS） is the key enzyme in the synthetic pathway of a quorum sensing autoinducer AI-2. LuxS from a 2,3-butanediol produced strain Klebisella pneumoniae CICC 10011 was cloned and characterized. The luxS gene is composed of 540 bp with 172 amino acids encoded. The Km value for S-ribosylhomo- cysteine（SRH） was （27±1） umol/L, kcat was （0.112±0.004） s-1 and kcat/Km was 4.4×103 L umol-1·s-1 at 25 ℃. LuxS was activated by divalent metal ions, the highest activity was detected with Co2＋ form, followed by Mg2＋, Ba2＋, Mn2＋, Fe2＋ and Ca2＋, and activation constant for Co2＋ is （16±2） umol/L.

关键词： S-Ribosylhomocysteinase(LuxS) Kinetics Characterization Klebsiellapneumoniae

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Luminescence Properties and Crystal Growth of Er/Yb Codoped KGd(WO_4)_2

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Chinese Journal of Structural Chemistry 2005年第8期24卷 879-884页

作者： WANG Yan TU Chao-Yang ZHU Zhao-Jie li jian-fu YOU Zhen-Yu WU Bai-Chang State Key Laboratory of Structural Chemistry fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences ChinaFuzhou Fujian 350002

In this paper, the spectral and luminescence properties of a series of KGd（WO4）2 powder samples codoped with different concentrations of Er^3＋ and Yb^3＋ were reported,and the best doping concentrations were found to be lat% Er^3＋ and 10at% Yb^3＋ for attaining the strongest intensity. The Er^3＋/yb^3＋ codoped KGd（WO4）2 crystal with good optical quality was grown by the TSSG method and the growth conditions were presented. The unpolarized absorption and emission spectra of the crystal have been measured. The strong absorption peak is at 980 nm with a FWHM of 65 nm, and the emission peak is at 1536 nm when pumped by 976 rim. The fluorescence lifetime of manifold ^4I13/2 is estimated to be 4.5 ms at room *** of Er, Yb：KGW crystal have shown it to have necessary combination of properties to get an effective generation of - 1.54 μm eye-safe radiation with laser diode pumping.

关键词： Er Yb:KGW crystal luminescence properties,crystal growth optical properties

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Enhancement of Two-photon Absorption by Ce^(3+) Sensitization in Organic Dyes

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Chemical Research in Chinese Universities 2007年第5期23卷 571-573页

作者： li jian-fu SUN Cheng-lin ZHOU Hai-ling XU li-hua YANG Qing-xin jianG Zhan-kui Department of Physics Linyi Normal University Linyi 276005 P. R. China College of Physics Jilin University Changchun 130021 P. R. China Department of Physics Yantai University Yantai 246005 P. R. China

The two-photon absorption（TPA）and TPA-induced frequency upconversion emission properties of the dyes 4-[P-（dicyanoethylamino）crystal]-N-methypyrdinium iodide and the complex of 4-[P-（dicyanoethylamino）crystal]-N-methypyrdinium iodide and Ce（NO3）3 were experimentally *** was found that the TPA cross section for the dye sensitized by Ce3＋ is two factors larger than that of the dye without being sensitized.A three-level system model of the dye molecules was used to analyze the enhancement of TPA by the sensitizer Ce3＋,which indicated that the sensitizer results in the increase of the transition dipole moment from the one-photon allowed excited state（1Bu）to the two-photon allowed excited state（2Ag）.

关键词： Two-photon absorption Frequency upconversion Organic dye

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Pheochromocytoma in a 49-year-old woman presenting with acute myocardial infarction:A case report

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World Journal of Clinical Cases 2021年第15期9卷 3752-3757页

作者： Hao-Yu Wu Yi-Wei Cao Tian-Jiao Gao jian-li fu Lei liang Department of Cardiology Shaanxi Provincial People’s HospitalXi'an 710068Shaanxi ProvinceChina Department of Electrocardiology Shaanxi Provincial People’s HospitalXi'an 710068Shaanxi ProvinceChina Department of Gastroenterology Xi’an Children’s HospitalXi'an 710068Shaanxi ProvinceChina Ultrasonic Diagnosis Center Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina

BACKGROUND Pheochromocytoma is a rare endocrine tumor arising from chromaffin cells and having extensive and profound effects on the cardiovascular system by continuously or intermittently releasing *** clinical manifestations of pheochromocytoma are diverse,and the typical triad,including episodic headache,palpitations,and sweating,only occurs in 24%of pheochromocytoma patients,which often misleads clinicians into making an incorrect *** herein report the case of a patient with intermittent chest pain and elevated myocardial enzymes for 2 years who was diagnosed with *** SUMMARY A 49-year-old woman presented with intermittent chest pain for 2 *** years ago,the patient experienced chest pain and was diagnosed with acute myocardial infarction,with 25%stenosis in the left *** patient still had intermittent chest pain after *** hours before admission to our hospital,the patient experienced chest pain with nausea and vomiting,lasting for 20 *** I and urinary norepinephrine and catecholamine levels were *** electrocardiogram indicated QT prolongation and ST-segment depression in leads II,III,aVF,and V3-V6.A coronary computed tomography angiogram revealed no evidence of coronary artery *** showed left ventricular enlargement and a decreased posterior inferior wall motion ***-enhanced computed tomography demonstrated an inhomogeneous right adrenal *** patient successfully underwent laparoscopic right adrenalectomy,and histopathology confirmed adrenal *** the first-year follow-up visits,the patient was *** abnormal changes on echocardiography and electro-cardiogram *** Clinicians should be aware of pheochromocytoma.A timely and accurate diagnosis of pheochromocytoma is essential for alleviating serious cardiac complications.

关键词： Pheochromocytoma Catecholamine Cardiac complications Acute myocardial infarction Chest pain Case report

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Arrhythmogenic right ventricular cardiomyopathy characterized by recurrent syncope during exercise:A case report

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World Journal of Clinical Cases 2021年第16期9卷 4095-4103页

作者： Hao-Yu Wu Yi-Wei Cao Tian-Jiao Gao jian-li fu Lei liang Department of Cardiology Shaanxi Provincial People’s HospitalXi'an 710068Shaanxi ProvinceChina Department of Electrocardiology Shaanxi Provincial People’s HospitalXi'an 710068Shaanxi ProvinceChina Department of Gastroenterology Xi’an Children’s HospitalXi’an 710003Shaanxi ProvinceChina Department of Ultrasonic Diagnosis Center Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina

BACKGROUND Arrhythmogenic right ventricular(RV)cardiomyopathy is a rare and currently underrecognized cardiomyopathy characterized by the replacement of RV myocardium by fibrofatty *** may be asymptomatic or symptomatic(palpitations or syncope)and may induce sudden cardiac death,especially during *** prevent adverse events such as sudden cardiac death and heart failure,early diagnosis and treatment of arrhythmogenic RV cardiomyopathy(ARVC)are *** report a patient with ARVC characterized by recurrent syncope during exercise who was successfully treated with combined endocardial and epicardial catheter *** SUMMARY A 43-year-old man was referred for an episode of syncope during ***,the patient experienced two episodes of syncope without a firm etiological *** electrocardiogram obtained at admission indicated ventricular tachycardia originating from the inferior wall of the right *** ventricular tachycardia was terminated with intravenous propafenone.A repeat electrocardiogram showed a regular sinus rhythm with negative T waves and a delayed S-wave upstroke from leads V1 to *** magnetic resonance imaging showed RV free wall thinning,regional RV akinesia,RV dilatation and fibrofatty infiltration(RV ejection fraction of 38%).An electrophysiological study showed multiple inducible ventricular tachycardia as of a focal mechanism from the right *** and epicardial voltage mapping demonstrated scar tissue in the anterior wall,free wall and posterior wall of the right *** potentials were also *** patient was diagnosed with ARVC and treated with combined endocardial and epicardial catheter ablation with a very satisfactory follow-up *** Clinicians should be aware of ARVC,and further workup,including imaging with multiple modalities,should be *** combination of epicardial and endocardial catheter ablation can lead to a good outcome.

关键词： Arrhythmogenic right ventricular cardiomyopathy Endocardial catheter ablation Epicardial catheter ablation Syncope Exercise Case report

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Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun fu Hong-Wei li jian-Hong Shi Tan li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

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Theoretical studies on structure-property relationships of cellulose and nitrocellulose ***,stability and conductivity

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Chinese Journal of Chemistry 1990年第5期8卷 390-395页

作者： XIAO,He-Ming FAN,jian-Fen li,Yong-fu East China Institute of Technology,Nanjing 210014 East China Institute of Technology Nanjing 210014

The banding and electronic structures of a series of long-chain macromolecules of cellu- lose,2-,3-,6-mononitrocellulose,2,3-,2,6-,3,6-dinitrocellulose and trinitrocellulose as well as their structural units(***-,double-or three-ring systems)have been calculated by both the EH and CNDO/2 *** increase of molecular total energies is consistent with the decrease of their stabilities at the three conformations of gg,gt and *** Mulliken bond order of O—NO_2 bond is the samllest in each molecule at any of the three conformations,which indicates that this bond is the weakest,and supports the view of initial homolytic cleavage of O—NO_2 bond on slow thermal *** band gap at the edge of the first Brillouin zone far surpasses 5 eV for cellu- lose,and is less than 3 eV for mono-,di-,and *** results show that cellulose is a typical insulator,as we know,and it can be predicted that nitrocellulose has electric conductivity similar to that of semiconductor.

关键词： Theoretical studies on structure-property relationships of cellulose and nitrocellulose I.Conformation stability and conductivity

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Growth and Characteristics of Nd^(3+):GdAl_3(BO_3)_4 Crystal

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Chinese Journal of Structural Chemistry 2003年第2期22卷 169-173页

作者： TU Chao-Yang② ZHU Zhao-Jie li jian-fu WU Bai-Chang (fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, fuzhou, fujian 350002, China) BRENIER Alain (Laboratoire de Physico-Chimie des Mat閞iaux Luminescents, Universit?Claude Bernard-Lyon1,UMR CNRS 5620, France) fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

Nd3+:GdAl3(BO3)4 (NGAB) crystal with the size of 30 mm was grown from the solvent system of K2O-Gd2O3-MoO3-B2O3 by combining accelerated seed rotation technology with medium seeded solution growth (MSSG) method, and its crystal structure has been determined by X-ray powder diffraction. It crystallizes in the trigonal system, space group R32 with a = 9.2734(2), c = 7.2438(1) ? V = 538 ?, Z = 3 and Dc = 4.379 g/cm3. The absorption and emission spectra of NGAB in the function of s and polarizations at room temperature have been measured. UV generation tuneable in 378～382 nm, green (531 nm) generation and blue generation tuneable in 436～443 nm as well as red (669 nm) generation by self-frequency changing were obtained with the output of 105, 119.5, 445 and 19 mJ/pulse, respectively, when the crystal was pumped by a dye laser.

关键词： flux crystal growth Nd3+:GdAl3(BO3)4 crystal self-frequency changing laser

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Sulfi de ore prospecting in carbon-containing stratum using comprehensive time-domain induced polarization and controlled-source audio-frequency magnetotellurics

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Applied Geophysics 2020年第5期17卷 809-822,903页

作者： Sun Ren-Bin Chu li-Xia Zhang Gui-Bin Cheng Qiu-Ming Xiang Yun-Chuan Hu Bin Zhang Chang-Rong li jian-fu Zhao Yi-Jun Development and Research Center China Geological SurveyBeijing 100037China China University of Geosciences Beijing100083China University of Salzburg Salzburg5020Austria.Clx_01@*** Inner Mongolia Geology Mineral Hohhot010010China.

Carbon-bearing stratum normally features low resistance and high *** the lithostratigraphy of the exploration area contains large amounts of carbon,the induced polarization anomaly caused by metal sulfide ore bodies will be inundated by the high polarization of carbon-containing wall *** this work,we adopted time-domain induced polarization(TDIP)and controlled-source audio-frequency magnetotellurics(CSAMT)on deep prospecting of the carbon-bearing stratum of the Ar Horqin Banner,Inner *** underground medium is divided into target geologic bodies according to the geological information within the known exploration line borehole,and the physical properties of various target geologic bodies are calculated using weighted averages to build a geologic-geophysical model that can fit the observation ***,we can determine the range and morphological characteristics of the electrical properties of the ore-bearing geologic bodies in the inversion results in the study *** we can use the characteristics summarized from the known exploration line to interpret unknown exploration *** indicated that,when the diff erence in physical properties between the ore body and interference wall rock is not clear,the geologic body can be classifi ed via the paragenetic(associated)assemblage relations of the underground *** interpretation is guided by the comprehensive physical properties of ore-bearing geologic bodies to avoid interferences.

关键词： TDIP CSAMT carbon-containing stratum sulfur containing lead-zinc-silver deposit weighted average of physical property

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