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Are nuclear loci ideal for barcoding plants? A case study of genetic delimitation of two sister species using multiple loci and multiple intraspecific individuals

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Journal of Systematics and Evolution 2011年第3期49卷 182-188页

作者： 1Qian WANG 1,2Qiu-Shi YU 1Jian-Quan LIU* 1(Molecular Ecology Group,key laboratory of Arid and Grassland Ecology,College of Life Sciences,lanzhou University,lanzhou 730000,china) 2(State key laboratory Breeding Base of desertification and Aeolian Sand Disaster combating,gansu Desert Control Research Institute,lanzhou 73.070,china) (Molecular Ecology Group Key Laboratory of Arid and Grassland Ecology College of Life Sciences Lanzhou University Lanzhou 730000 China) (State key laboratory Breeding Base of desertification and Aeolian Sand Disaster combating Gansu Desert Control Research Institute Lanzhou 730070 China)

Considerable debate remains as to which DNA region should be used to barcode *** different chloroplast(cp) DNA regions(rbcL,matK,and trnH-psbA) and nuclear ribosomal internal transcribed regions(ITS) have been suggested as suitable barcodes in ***,low-copy nuclear loci were also suggested to be potentially ideal barcode *** aim of the present study was to test the effectiveness of these proposed DNA fragments and five additional low-copy loci(CHS,DET1,COP1,PGIC1,and RPS2;comprising both coding and non-coding regions) in barcoding closely related *** examined the divergences within and between two species of Pugionium(Brassicaceae).We failed to find any interspecific variation from three cpDNA fragments with which to discriminate the two ***,a single base mutation in the internal transcribed spacer(ITS) could discriminate between the two species *** found more variations among all individuals of the two species using each of the other five low-copy nuclear ***,only alleles from one locus(DET1) of the five low-copy loci related to ?owering regulations was able to distinguish the sampled individuals into two *** failed to amplify the corresponding fragments out of Brassicaceae using the designed DET1 *** further discussed the discrimination power of different loci due to incomplete lineage sorting,gene ?ow,and species-specific *** results highlight the possibility of using the nuclear ITS as a core or complementary fragment to barcode recent diverged species.

关键词： chloroplast DNA DNA barcoding internal transcribed spacer(ITS) low-copy nuclear loci Pugionium.

Comparison of sensible and latent heat fluxes during the transition season over the western Tibetan Plateau from reanalysis datasets

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Progress in Natural Science:Materials International 2009年第6期19卷 719-726页

作者： Yang Cui, Chenghai Wang Disaster Reduction key laboratory of gansu province, College of Atmospheric Sciences, lanzhou University, lanzhou 730000, china Disaster Reduction key laboratory of gansu province College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

The sensible and latent heat fluxes during the transition season over the western Tibetan Plateau from the NCEP-1 (NCEP/NCAR Reanalysis 1), AR-Ⅱ (NCEP-DOE Reanalysis 2) and ERA40 reanalysis datasets were compared and analyzed. The results show that the phase change in soil moisture has a significant effect on the sensible and latent heat fluxes over the western Tibetan Plateau (TP) due to the freezing-thawing processes during the transition from the dry to the wet period. The uncertainties in the sensible and latent heat fluxes over the western TP are quite high in the reanalysis data, and depend largely on the success of the soil moisture simulations in the models. Improving the hydrological process simulations in the land-surface models in seasonally frozen ground and in the active frozen soil layer may be an effective way of enhancing the reliability of the surface heat fluxes from the reanalysis data over the Tibetan Plateau.

关键词： Western Tibetan Plateau Surface heat fluxes Reanalysis data Transition season Freezing-thawing process

Effects of the Extract of Ammopiptanthus mongolicus cheng f. (JA1) on Induction of Apoptosis of HepG2 in vitro and Its Molecular Mechanisms

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Biomedical and Environmental Sciences 2006年第2期19卷 118-123页

作者： LEI JIA LI-ZHE AN key laboratory of Arid and Pastoral Agroecology of Ministry of Education and School of Life Sciences LanzhouUniversity Lanzhou 730000 Gansu China key laboratory of Desert and desertification Cold and Arid Region Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

Objective To study the effects and the mechanisms of extract from a leguminous plant （Ammopiptanthus mongolicus cheng f.）（JAl ） in northwest china on inducing apoptosis and inhibiting proliferation of HepG2 hepatocarcinoma cell in vitro. Methods The HepG2 cell line was used as target cells. The effect of 3A 1 on HepG2 cell growth was detected by microculture tetrazolium assay （MTr）, flow cytometry assay, DNA agarose gel electrophoresis and transmission electronic microscopy. The expressive effect of the wt-p53 in HepG2 cells was analyzed with p53 protein test-reagent. Results JAl not only had significant anti-proliferative effects depending upon time and dosage, but also induced apoptosis of HepG2 cells. Apoptotic typical morphological changes were observed in JAl-treated HepG2 cells under transmission electronic microscope, ＂Sub-G 1＂ phase peak occurred in flow cytometry and DNA ＂ladder＂ was found in DNA agarose gel electrophoresis. The expression of the wt-p53 increased in vitro, and 3Al-treated HepG2 and the positive cell percentage of the wt-p53 protein also increased. Conclusions JAl could obviously induce apoptosis and inhibit proliferation of HepG2 cells in vitro, and these effects are closely related with the increase of wt-p53 expression. JAl can be used as a good source of medicinal plant for the treatment of hepatocarcinoma.

关键词： Extract from Ammopiptanthus mongolicus cheng f. (JAl) HepG2 Apoptosis Induction wt-p53

A piecewise-integration method for simulating the influence of external forcing on climate

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Progress in Natural Science:Materials International 2008年第10期18卷 1239-1247页

作者： Zhifu Zhang Chongjian Qiu Chenghai Wang key laboratory of Arid Climatic Changing and Reducing Disaster of gansu province,College of Atmospheric Sciences,lanzhou University.lanzhou 730000.china key laboratory of Arid Climatic Changing and Reducing Disaster of gansu province College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

Climate drift occurs in most general circulation models (GCMs) as a result of incomplete physical and numerical representation of the complex climate system,which may cause large uncertainty in sensitivity experiments evaluating climate response to changes in external *** solve this problem,we propose a piecewise-integration method to reduce the systematic error in climate sensitivity studies. The observations are firstly assimilated into a numerical model by using the dynamic relaxation technique to relax to the current state of atmosphere,and then the assimilated fields are continuously used to reinitialize the simulation to reduce the error of climate simulation. When the numerical model is integrated with changed external forcing,the results can be split into two parts,background and pertur- bation fields,and the background is the state before the external forcing is *** piecewise-integration method is used to con- tinuously reinitialize the model with the assimilated field,instead of the ***,the simulation error of the model with the external forcing can be *** this way,the accuracy of climate sensitivity experiments is greatly *** with a simple low-order spectral model show that this approach can significantly reduce the uncertainty of climate sensitivity experiments.

关键词： Climate model External forcing Sensitivity experiment Low-order spectral model Dynamic relaxation technique

Magnetic characteristics of dustfall in urban area of north china and its environmental significance

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Science china Earth Sciences 2007年第11期50卷 1724-1732页

作者： XIA DunSheng1,2, YANG LiPing2, MA JianYing1, YU Ye1, WANG Guan2 & CHEN FaHu2 1 key laboratory of Desert and desertification, Institute of Cold and Arid Regions Environmental and Engineering, Chinese Academy of Sciences, lanzhou 730000, china 2 CAEP, key laboratory of West china’s Environmental System (Ministry of Education), lanzhou University, lanzhou 730000, china key laboratory of Desert and desertification Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China CAEP Key Laboratory of West China’s Environmental System (Ministry of Education) Lanzhou University Lanzhou China

Urban particulate pollutants not only affect urban air quality but also directly threaten public health. lanzhou has been one of the most seriously polluted cities in the world due to its special geophysical location and weather conditions, which makes it an ideal place for urban particulate pollution study. In this study a set of environmental magnetic parameters (χlf, χfd%, χARM, SIRM, HIRM, SOFT and back field IRM) were measured and analyzed for the dustfall samples collected monthly during 1997.4―2000.5 and 2004.11―2005.10 at lanzhou University campus (KLD and CCS) and at a clear site of Gaolanxian (GLX). Results demonstrate that the main magnetic minerals in the dustfall are magnetite, with some maghaemite and haematite. Cross plots of Mrs/Ms vs. Bcr/Bc and χfd% vs. χARM/SIRM indicate that the main magnetic grain sizes are pseudo-single-domain (PSD). The high concentration of magnetic min-erals in the dustfall indicates that lanzhou is seriously polluted. The main pollution sources are an-thropogenic activities and nature dust, with the former posing a great threat during the whole year, which is different from the general view that the natural dust is the main contributor in summer. With great efforts of the government and local authority in the past decades, the air quality in lanzhou has been improved in winter, but it is not so obvious in summer. This study also reveals that as a simple, rapid and accurate technology, environmental magnetism could be a valuable tool for urban pollution study.

关键词： environmental magnetism,dustfall,air pollution,lanzhou

重熔对Al-Ti-La中间合金中Ti_(2)Al_(20)La相的影响

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有色金属工程 2024年第8期14卷 56-66页

作者：丁万武田旭东陈建超安家志余海存魏振鹏杨成亮兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050 兰州理工大学材料科学与工程学院兰州730050 甘肃东兴铝业有限公司甘肃嘉峪关735100

通过扫描电镜、X射线衍射和电子探针等分析研究了重熔过程中不同保温时间和温度对Al-Ti-La中间合金中Ti_(2)Al_(20)La相的含量、形态尺寸和稳定性的影响。结果表明:在750℃下,随着保温时间的延长,Ti_(2)Al_(20)La相的溶解度逐渐增大,含... 详细信息

通过扫描电镜、X射线衍射和电子探针等分析研究了重熔过程中不同保温时间和温度对Al-Ti-La中间合金中Ti_(2)Al_(20)La相的含量、形态尺寸和稳定性的影响。结果表明:在750℃下,随着保温时间的延长,Ti_(2)Al_(20)La相的溶解度逐渐增大,含量由未处理的20.776%下降至13.72%,形态由块状演变为圆整和细小的片状,长宽比由2.33下降至1.52;在1000℃下,保温15 min后溶解度较大,含量降低至4.5%,形态演变为尖锐的长条状,长宽比上升至2.55;溶解产生的La原子与Al在晶界处形成La-Al金属间化合物(IMC),Ti原子在基体中的分布密度随保温时间的延长和保温温度的升高而增高,以游离态均匀分布在基体中。

关键词： Al-Ti-La合金 Ti_(2)Al_(20)La 重熔保温时间

A study on the reaction of 2'-hydroxychalcones with I_2-H_2SO_4-DMSO system

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Chinese Journal of Chemistry 1994年第1期12卷 73-78页

作者： ZHANG, Fang-Jie LI, Yu-LinState key laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, lanzhou University , lanzhou, gansu 73000, china State key laboratory of Applied Organic Chemistry and Institute of Organic Chemistry Lanzhou University Lanzhou Gansu 73000 China

The reaction of 2'-hydroxychalcones with I_2-H_2SO_4-DMSO system has been studied. The results obtained by us are entirely different from those reported in the literature. The mechanism of this reaction has also been ... 详细信息

关键词： Reaction 2'-hydroxychalcone I_2-H_2SO_4-DMSO system.

Effect of Occupational Manganese Exposure on Uric Acid Levels in Human Urine

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Biomedical and Environmental Sciences 2011年第3期24卷 222-227页

作者： SUN XiaoMing LIU YeWei WANG ZhenQuan LI HongBing LIU Yun DI DuoLong key laboratory of Chemistry of Northwestern Plant Resources and key laboratory for Natural Medicine of gansu province Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 Gansu China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Institute of Nutrition and Food Hygiene School of Public Health Lanzhou University Lanzhou 730000 Gansu China

Objective To investigate the effect of long-term and low-level occupational Mn exposure on the level of uric acid （UA） in human urine. Methods In this study, 65 volunteers were recruited, who were working on welding and foundry work in an plant in gansu province, china. Additionally, 29 control samples were collected from individuals who did not have any history of excessive Mn exposure. An improved high performance liquid chromatography system equipped with a diode-array detector （HPLC-DAD） method was developed to determine the UA level in human urine. A Spectra AA 220 Atomic Absorption Spectrophotometer （AAS） was used to measure the Mn level in the urine. Results The analytical method was validated acceptable accuracy, precision, and recovery significantly lower than that of control samples for concentrations ranging from 3.82-45.84 pg/mL with Overall, the UA levels of Mn exposure samples were （P〈O.O5）. Conclusion The practical method developed here is suitable for both routine monitoring of UA level in human urine and metabolism research. Long-term and low-level occupational Mn exposure may lead to a lower UA level in urine, and UA might be an indicator of the early stage of manganism.

关键词： High-performance liquid chromatography Uric acid Occupational Mn exposure

Parametric instabilities in quantum plasmas with electron exchange-correlation effects

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Chinese Physics B 2013年第2期22卷 341-346页

作者：何彩霞薛具奎 key laboratory of Atomic & Molecular Physics and Functional Materials of gansu province College of Physics and Electronics EngineeringNorthwest Normal University

Parametric instabilities induced by the nonlinear interaction between high frequency quantum Langmuir waves and low frequency quantum ion-acoustic waves in quantum plasmas with the electron exchange-correlation effects are *** using the quantum hydrodynamic equations with the electron exchange-correlation correction,we obtain an effective quantum Zaharov model,which is then used to derive the modified dispersion relations and the growth rates of the decay and four-wave *** influences of the electron exchange-correlation effects and the quantum effects on the existence of quantum Langmuir waves and the parametric instabilities are discussed in *** is shown that the electron exchange-correlation effects and quantum effects are strongly *** quantum Langmuir wave can propagate in quantum plasmas only when the electron exchange-correlation effects and the quantum effects satisfy a certain *** electron exchange-correlation effects tend to enhance the parametric instabilities,while quantum effects suppress the instabilities.

关键词： parametric instabilities quantum Langmuir waves electron exchange-correlation