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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2, DING Lin1, XIA Guoying3 & WANG Lei2 1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, china 2. Faculty of Earth Sciences and Mineral Resources, china University of Geosciences, beijing 100083, china 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 300170, china 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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Biologically effective radiation of solar ultraviolet radiation and the depletion of stratospheric ozone

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Journal of Environmental Sciences 1994年第3期6卷 373-381页

作者： Wang Shaobin Su Weihan(Research center for Eco-Environmental Sciences,Chinese Academy of Sciences),beijing 100085,china) Wei Dingwen(Institute of Atmospheric Physics,Chinese Academy or Sciences),beijing 100029,china)

Based on the biological action spectra and total UV-B radiation in the atmosphere,the effective UV-dose for DNA, erythema,and plant at different seasons in the last decade,and their future change in beijing area were *** results indicate that the maxi- mum of biologically effective radiation dose at noontime is in July and the minimum is in January. From 1980 to 1989 biologically effective radiation dose have increased with the average rates of about 0.6,0.7 and 1.1 mW/m￣2 per year for January, April and October,while in July the trend of radiation dose is not ln evidence. For 1% reduction of ozone concentration radiation amplification factor for DNA,erythema and plant are 2.3,2.3 and 1.4 and for 30% reduction of ozone concentration the RAF for DNA,erythema and plant are 4.2,4.0 and 2.1,respectively.

关键词： UV-B ozone depletion biological effects solar radiation.

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Information extraction and CT reconstruction of liver images based on diffraction enhanced imaging

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Progress in Natural Science:Materials International 2009年第8期19卷 955-962页

作者： Chunhong Hua,b, Tao Zhao a, Lu Zhanga, Hui Lia, Xinyan Zhao c, Shuqian Luoa, a College of Biomedical Engineering, Capital Medical University, beijing 100069, china b National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, beijing 100080, china c Liver Research center, beijing Friendship Hospital, Capital Medical University, beijing 100050, china [a]College of Biomedical Engineering Capital Medical University Beijing 100069 China [b]National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China [c]Liver Research Center Beijing Friendship Hospital Capital Medical University Beijing 100050 China

X-ray phase-contrast imaging (PCI) is a new emerging imaging technique that generates a high spatial resolution and high contrast of biological soft tissues compared to conventional radiography. Herein a biomedical application of diffraction enhanced imaging (DEI) is presented. As one of the PCI methods, DEI derives contrast from many different kinds of sample information, such as the sample’s X-ray absorption, refraction gradient and ultra-small-angle X-ray scattering (USAXS) properties, and the sample information is expressed by three parametric images. Combinedwith computed tomography (CT), DEI-CT can produce 3D volumetric images of the sample and can be used for investigating micro-structures of biomedical samples. Our DEI experiments for liver samples were implemented at the topography station of beijing Synchrotron radiation Facility (BSRF). The results show that by using our provided information extraction method and DEI-CT reconstruction approach, the obtained parametric images clearly display the inner structures of liver tissues and the morphology of blood vessels. Furthermore, the reconstructed 3D view of the liver blood vessels exhibits the micro blood vessels whose minimum diameter is on the order of about tens of microns, much better than its conventional CT reconstruction at a millimeter resolution. In conclusion, both the information extraction method and DEI-CT have the potential for use in biomedical micro-structures analysis.

关键词： Diffraction enhanced imaging Computed tomography Information extraction X-ray Liver

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Synthesis of vertically aligned carbon nanotube arrays on silicon substrates

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Science china(Technological Sciences) 2004年第5期47卷 616-624页

作者： ZHENG Ruiting1, CHENG Guoan1, PENG Yibin1, 2, ZHAO Yong1, 3, LIU Huaping1 & LIANG Changlin1 1. Key Laboratory of radiation Beam Technology and Materials Modification of Ministry of Education, Department of Materials Science and Engineering, beijing Normal University, beijing 100875, china 2. School of Science, Civil Aviation University of china, Tianjin 300300, china 3. Department of Physics, Nanchang University, Nanchang 330047, china Correspondence should be addressed to Zheng Ruiting 1. Key Laboratory of radiation Beam Technology and Materials Modification of Ministry of Education Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 2. School of Science Civil Aviation University of China 300300 Tianjin China 3. Department of Physics Nanchang University 330047 Nanchang China

The growth of well-aligned carbon nanotube (CNT) arrays using a heat chemical vapor deposition system on silicon substrates is reported. The growth properties of CNT arrays are studied as a function of synthesis conditions. It is found that 750°C and 10 nm Fe film are suitable conditions for the growth of well-aligned CNT arrays. CNT arrays with a uniform diameter, thick tube wall and firm cohesion to the Si substrate can be grown for C2H2 concentration of 27%. Based on the experiment, the processes of improving the alignment of CNT arrays and cohesion between CNT arrays and Si substrates are discussed.

关键词： carbon nanotubes, vertically aligned, silicon substrate, chemical vapor deposition.

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Pharmacokinetic Study on Hyperoside in Beagle’s Dogs

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Chinese Herbal Medicines 2012年第3期4卷 213-217页

作者： AI Guo 1, 2 , HUANG Zheng-ming 2 , LIU Chang-xiao 3 1. Institute of radiation Medicine, Academy of Military Medical Sciences, beijing 100850, china 2. Department of Pharmacy, 302 Hospital of PLA, beijing 100039, china 3. Tianjin Institute of Pharmaceutical Research, Tianjin 300193, china [a] Institute of radiation Medicine Academy of Military Medical Sciences Beijing 100850 China [b] Department of Pharmacy 302 Hospital of PLA Beijing 100039 China [c] Tianjin Institute of Pharmaceutical Research Tianjin 300193 China

Objective To develop and validate a simple, rapid, sensitive, and reproducible HPLC method for determination of hyperoside in plasma of dogs and for the subsequent pharmacokinetic (PK) study. Methods An accurate and reproducible HPLC-UV method was developed and validated for the determination of hyperoside in plasma of dogs, using kaempferol as internal standard. The plasma samples of dogs following ig administration of hyperoside were analyzed for the detection of quercetin after enzymatic hydrolysis treatment with combined β-glucuronidase and sulphatase. The analytes were separated on a Diamonsil C 18 column (250 mm × 4.6 mm, 5 μm). The mobile phase consisted of methanol-buffer solution (0.1 mol/L NH 4 Ac + 0.3 mmol/L EDTA-Na 2 )-acetic acid (60:40:1) and was delivered at a flow rate of 1 mL/min. The UV detector was set at 370 nm and the column temperature was maintained at 35 ℃. The sample injection volume was 20 μL. Data were collected and analyzed using the ANASTAR software. PK parameters were calculated with DAS software (2.0). Results Linear relationships were validated over the range of 0.01-1 μg/mL for hyperoside (r = 0.9997). The intra- and inter-day precision values for all samples were within 10.0%, and the accuracies of intra- and inter-day assays were within the range of 92.4%-102.4%. The validated method was successfully used to determine the hyperoside concentration in plasma of dogs for up to 12 h, after a single ig administration (25 mg/kg). The mean PK parameters for male and female dogs were as follows: C max (0.18 ± 0.05) and (0.16 ± 0.05) μg/mL, AUC 0-∞ (0.79 ± 0.34) and (0.86 ± 0.27) μg/(mL·h), t 1/2(ka) (0.89 ± 0.41) and (0.88 ± 0.28) h, respectively. Statistical analysis on the PK of hyperoside in male and female groups showed that sex had no significant impact on the PK of hyperoside (P > 0.05). Conclusion The method is able and sufficient to be used in drug PK studies of hyperoside.

关键词： Beagle’s dogs HPLC hyperoside kaempferol pharmacokinetics

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KAI1 inhibits HGF-induced invasion of pancreatic cancer by sphingosine kinase activity

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 201-208页

作者： Xu Liu,Xiao-Zhong Guo,Wei-Wei Zhang,Zhuo-Zhuang Lu,Qun-Wei Zhang, Hai-Feng Duan and Li-Sheng Wang State Key Laboratory of Cancer Biology and Institute of Digestive Diseases,Xijing Hospital of Digestive Disease,Fourth Military Medical University,Xi’an 710032,china Department of Gastroenterology,Shenyang General Hospital of PLA,Shenyang 110016, china Department of Experimental Hematology,beijing Institute of radiation Medicine,beijing 100850,china [a] State Key Laboratory of Cancer Biology and Institute of Digestive Diseases Xijing Hospital of Digestive Disease Fourth Military Medical University Xi'an 710032 China [b] Department of Gastroenterology Shenyang General Hospital of PLA Shenyang 110016 China [c] Department of Experimental Hematology Beijing Institute of Radiation Medicine Beijing 100850 China

BACKGROUND:KAI1/CD82 has been reported to attenuate the process of metastases in a variety of tumors;however,its mechanism of action in invasion has not been fully elucidated. The present study aimed to investigate the importance of KAI1 in invasion and its correlation with activation of sphingosine kinase(SPK)in human pancreatic cancer PANC1 and Miapaca-2 cell lines. METHODS:The expression of KAI1 in PANC1 and Miapaca-2 cells,which was mediated by recombinant adenovirus(Ad-KAI1), was assessed by a flow cytometer and Western *** successful infection was established,in vitro growth curve and invasive ability in Boyden Chamber assay were *** presence of KAI1 correlating with c-Met and SPK was detected by co-immunoprecipitation and[γ-32P]ATP incorporation. RESULTS:KAI1 genes had no significant effects on the curve representing cell *** infection with the KAI1 gene,decreased invasive ability in the Boyden Chamber assay was observed in PANC1 and Miapaca-2 cells that were induced by hepatocyte growth ***-expression of KAI1 in the cells led to the deactivation of SPK and a decreased level of intracellular *** correlation was observed between c-Met and KAI1 during co-immunoprecipitation. CONCLUSION:The results of this study for the first time demonstrated a regulatory role for KAI1 in SPK activation, which leads to decreased invasive ability in disease progression of human pancreatic cancer.

关键词： adenovirus vector KAI1 gene sphingosine kinase pancreatic cancer cell lines

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Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： WANG HongBo1,2 & ZHAO ChangYin1 1 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, china 2 Graduate University of Chinese Academy of Sciences, beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72, DTM94, NRLMSISE00 and JB2006, are discussed. The CHAMP accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMP observations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.7200) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2006 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2006’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on October 26, 2003, JB2006 has been in best agreement with CHAMP observations. All in all, the new indices may improve thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMP accelerometer data neutrals density model

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Recruitment of stem cells by hepatocyte growth factor via intracoronary gene transfection in the postinfarction heart failure

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Science china(Life Sciences) 2007年第6期50卷 748-752页

作者： YANG ZhiJian1, WANG Wei1, MA DongChao1, ZHANG YouRong2, WANG LianSheng1, ZHANG YuQing1, XU ShunLin1, CHEN Bo1, MIAO DengShun3, CAO KeJiang1 & MA WenZhu1 1 Department of Cardiovascular Medicine, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, china 2 Department of Experimental Hematology, beijing Institute of radiation Medicine, beijing 100850, china 3 Department of Experimental anatomy, Nanjing Medical University, Nanjing 210029, china Department of Cardiovascular Medicine the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China Department of Experimental Hematology Beijing Institute of Radiation Medicine Beijing 100850 China Department of Experimental anatomy Nanjing Medical University Nanjing 210029 China

We aim to study the amelioration effect of adenovirus5-mediated human hepatocyte growth factor gene transfer on postinfarction heart failure in swine model. Twelve Suzhong young swine were randomly divided into 2 groups of 6 pigs each: Ad5-HGF group and mock-vector Ad5 group. Four weeks after ligation of the left anterior descending coronary artery, Ad5-HGF was intracoronarily transferred into the myocardium. Simultaneously, gate cardiac perfusion imaging was performed to evaluate the heart function. Three weeks later, gate cardiac perfusion imaging was performed again, then the hearts were removed and sectioned for immunohistochemical examination to illustrate the effects of Ad5-HGF on infarcted myocardium. The expression of HGF was examined by ELISA. The results were: (1) compared with the mock-vector Ad5 group, high expression of human HGF was observed in the myocardium of Ad5-HGF group; (2) in the Ad5-HGF group, the number of CD117+ cells co-expressing c-Met per mm2 was significantly larger; (3) the improvement in LVEF was greater in the Ad5-HGF group than in the mock-vector Ad5 group. We concluded that: (1) high expression of human HGF was observed in the myocardium through intracoronary gene transfection; (2) HGF can improve the mobilization of CD117+/c-Met+ stem cells into ischemic myocardium. The amelioration effect of HGF on postinfarction heart failure could not be limited to stimulating angiogenesis, anti-apoptosis, anti-fibrosis, but was also involved in the recruitment of stem cells into myocardium.

关键词： gene therapy, stem cells, postinfarction heart failure

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Bitstream decoding and SEU-induced failure analysis in SRAM-based FPGAs

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Science china(Information Sciences) 2012年第4期55卷 971-982页

作者： WANG ZhongMing 1,2,YAO ZhiBin 2,GUO HongXia 2 & LV Min 1 1 Department of Engineering Physics,Tsinghua University,beijing 100084,china 2 Northwest Institute of Nuclear Technology,Xi'an 710024,china 1. Department of Engineering Physics Tsinghua University Beijing 100084 China2. Northwest Institute of Nuclear Technology Xi’an 710024 China

Reconfigurable SRAM-based FPGAs are highly susceptible to radiation induced single-event upsets (SEUs) in space *** bit flip in FPGAs configuration memory may alter user circuit permanently without proper bitstream reparation,which is a completely different phenomenon from upsets in traditional memory *** is important to find the relationship between a programmable resource and corresponding control bit in order to understand the impact of this *** this paper,a method is proposed to decode the bitstream of FPGAs from Xilinx Corporation,and then an analysis program is developed to parse the netlist of a specific design to get the configuration state of occupied programmable logic and *** that,an SEU propagation rule is established according to the resource type to identify critical logic nodes and paths,which could destroy the circuit topological *** decoded relationship is stored in a *** database is queried to get the sensitive bits of a specific *** result can be used to represent the vulnerability of the system and predict the on orbit system failure *** analysis tool was validated through fault injection and accelerator irradiation experiment.

关键词： radiation effect single-event effect single-event upset SRAM-based FPGA fault injection

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Study of safety performance of the ^(241)Am fire alarm source

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Nuclear Science and Techniques 2000年第1期11卷 34-40页

作者： FENG Gen-Sheng (china institute of Afomic Eachs, beijing 10241s) 中国原子能科学院北京 102413

The safety performance of 241Am fire alarm sources made by using powder metallurgical technology has been preliminarily studied, so as to determine an allowable maximum energy limit value of the alpha particles outgoing from this kind of sources in light of radiation safety and the present technology. The yielded results show that 241Am leak has not been found when the peak energy of the alpha energy spectrum of this kind of sources is less than 4.96 MeV.

关键词：镅241 火警源辐射源火灾监测安全性能

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