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Hepatic perfusion disorders: Etiopathogenesis and related diseases

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World Journal of Gastroenterology 2006年第20期12卷 3265-3270页

作者： jin-Lin Tian jin-shan Zhang Department of Radiology Chinese PLA General Hospital Beijing 100853 China

In this article, we have reviewed the hepatic perfusion disorder （HPD）, etiopathogenesis of HPD and corresponding diseases. Review of the literature was based on computer searches （PubMed, Index Medicus） and personal experiences. We considered HPD reflects perfusion differences due to redistribution of arterial blood flow among segments, subsegments and lobes of the liver. The plain CT scan findings of HPD manifests as triangular or wedge-shaped areas of low attenuation. On contrast-enhanced CT scan, HPD manifests multiple （or single） transient wedge-shaped, rotundloid or irregular appearance, homogeneous hyperattenuation （in less cases, hypoattenuation） during the hepatic arterial phase （HAP） and isoattenuated or slightly hyperattenuated areas during the portal arterial phase. Dynamic enhanced magnetic resonance （MR） features are similar to enhanced CT scan. Angiographic findings include non-opacification of portal vein on portograms or wedge-shaped segmental staining in arterial and parenchymal phases on hepatic angiograms. The causes of HPD are arterioportal shunts （APS）, intrahepatic vascular compressions and portal vein occlusion, steal phenomenon by hypervascular tumors, vascular variations and any other unknown reasons. It is very important for radiologists to be familiar with the various appearances of HPD to avoid false-positive diagnosis of pseudolesions and not to overestimate the extent of the disease.

关键词： Etiopathogenesis Hepatic perfusion disorders Diseases

Theoretical Studies on the Si(001)-SiO_2 Interface Structure

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Chinese Journal of Structural Chemistry 2006年第6期25卷 647-652页

作者： ZHOU Ming-Xiu yang Chun DENG Xiao-Yan YU Wei-Fei LI jin-shan Key Laboratory of Computer Software Sichuan Normal University Chengdu Sichuan 610068 China China Academy of Engineering Physics Mianyang Sichuan 621000 China

Novel models （2× 1） of Si（001）-SiO2 interface structure have been established. The method of the first-principle General Gradient Approximation （GGA） is employed to structurally optimize the established theoretical models under the K-point space of periodic boundary condition. The structures after optimization have been analyzed, and the results show that the interfaces present in disordered state and both Si-O-Si and Si=O structures exist. Meanwhile, the bonding of surface structure is analyzed via the graphics of electron localization function（ELF）.

关键词： Si/SiO2 DFT interface structure

Carbon emissions induced by farmland expansion in China during the past 300 years

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Science China Earth Sciences 2019年第2期62卷 423-437页

作者： Xuhong yang Xiaobin jin Xiaomin XIANG Yeting FAN jing LIU Wei shan Yinkang ZHOU School of Geographic and Oceanographic Sciences Nanjing University

Scientific assessment of the accounting over carbon in the terrestrial ecosystem in the process land use/land cover changes caused by human activities will help reduce the uncertainty in estimating carbon emissions from the terrestrial ecosystem. This study employs a bookkeeping model to estimate the carbon emissions from farmland reclamation in China during the past 300 years based on the annual rate of land use changes(derived from historical natural vegetation, farmland data), preset carbon density and coefficients of disturbance curves. We find out that:(1) there was a net increase of 79.30×10~4km^2 in national farmland; about 65% of reclaimed farmland had been forest land and 26% of that had been grass land previously;(2) the total amount of carbon emissions from farmland expansion in China had been between 2.94 and 5.61 Pg with the median 3.78 Pg during the past 300 years; specifically, carbon emissions of vegetation were 1.58 Pg while those of soil ranged from 1.35 Pg to4.03 Pg with the median 2.20 Pg;(3) carbon emissions vary greatly across various ecosystems: the emissions were most from forest land, and then grass land and swamps, and the least from shrubs; deserts functioned more likely to be carbon stock in the process of land reclamation;(4) along the time line, carbon emissions had decreased first and then increased while the peak emissions occurred in the first half of 20 th century; and spatially, carbon emissions were most released in Northeast and Southwest China; Northwest China was of the minimum carbon emissions.

关键词： Farmland expansion Carbon emission Bookkeeping model China 300 years

Single-molecule RNA capture-assisted droplet digital loop-mediated isothermal amplification for ultrasensitive and rapid detection of infectious pathogens

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Microsystems & Nanoengineering 2023年第5期9卷 151-160页

作者： Liying Jiang Xianghao Lan Linjiao Ren Zhiyuan jin Xuchen shan Mingzhu yang Lingqian Chang School of Electrical and Information Engineering Zhengzhou University of Light Industry450002 ZhengzhouChina Academy for Quantum Science and Technology Zhengzhou University of Light Industry450002 ZhengzhouChina Beijing Advanced Innovation Center for Biomedical Engineering School of Biological Science and Medical EngineeringBeihang University100191 BeijingChina School of Physics Beihang University100191 BeijingChina Beijing Research Institute of Mechanical Equipment 100143 BeijingChina

To minimize and control the transmission of infectious diseases,a sensitive,accurate,rapid,and robust assay strategy for application on-site screening is ***,we report single-molecule RNA capture-assisted digital RT-LAMP(SCADL)for point-of-care testing of infectious *** RNA was captured and enriched by specific capture probes and oligonucleotide probes conjugated to magnetic beads,replacing laborious RNA *** generation,amplification,and the recording of results are all integrated on a microfluidic *** assaying commercial standard samples,quantitative results precisely corresponded to the actual concentration of *** method provides a limit of detection of 10 copies mL−1 for the N gene within 1 h,greatly reducing the need for skilled personnel and precision *** ultrasensitivity,specificity,portability,rapidity and user-friendliness make SCADL a competitive candidate for the on-site screening of infectious diseases.

关键词： SCAD recording competitive

Synthesis of an optically active intermediate for A-ring of 19-nor-1α,25-dihydroxyvitamin D3

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Chinese Chemical Letters 2007年第3期18卷 261-262页

作者： shan Qian Li Hai Lei Tang jin Cheng yang Yong Wu Key Laboratory of Drug Targeting and Novel Drug Delivery Systems West China School of Pharmacy Sichuan University Chengdu 610041 China

An optically active intermediate 5 for A-ring of 19-nor-1α,25-dihydroxyvitamin D3 2 has been synthesized in five steps, starting from readily available, inexpensive v（＋）-xylose 6 with good yield.

关键词： A-ring of 19-nor-1α,25-dihydroxyvitamin D3 Intermediate Synthesis

Optimization of thermal processing parameters of Ti555211 alloy using processing maps based on Murty criterion

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Rare Metals 2016年第2期35卷 154-161页

作者： Zhen An jin-shan Li Yong Feng State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Isothermal compression testing of Ti555211 titanium alloys was carried out at deformation temperatures from 750 to 950 °C in 50 °C intervals with a strain rate of0.001-1.000 s^（-1）. The high-temperature deformation behavior of the Ti555211 alloy was characterized by analysis of stress-strain behavior, kinetics and processing maps. A constitutive equation was formulated to describe the flow stress as a function of deformation temperature and strain rate, and the calculated apparent activation energies are found to be 454.50 and 207.52 k J mol^（-1）in the a b-phase and b-phase regions, respectively. A processing map based on the Murty instability criterion was developed at a strain of 0.7. The maps exhibit two domains of peak efficiency from 750 to 950 °C. A ＊60 % peak efficiency occurs at 800-850 °C/0.001-0.010 s^（-1）. The other peak efficiency of ＊60 % occurs at C950 °C/0.001-0.010 s^（-1）, which can be considered to be the optimum condition for high-temperature working of this ***, at strain rates of higher than 1.000 s^（-1）and deformation temperatures of 750 and 950 °C, clear process flow lines and bands of flow localization occur in the hightemperature deformation process, which should be avoided in Ti555211 alloy hot processing. The mechanism in stability domain and instability domain was also discussed.

关键词： Ti555211 titanium alloy High temperature Deformation behavior Processing maps

Microstructure evolution of a new near-β titanium alloy:Ti555211 during high-temperature deformation

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Rare Metals 2015年第11期34卷 757-763页

作者： Zhen An jin-shan Li Yong Feng State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The isothermal compression testing of Ti555211 titanium alloys was carried out at deformation temperatures from 750 to 950 ℃ in 50 ℃ intervals,with strain rate of 0.001-1.000 s-1and height reduction of 20%-60%.The effect of processing parameters（deformation temperature,strain rate and deformation degree） on the microstructure evolution and the microstructure variables was *** results show that the content of primary α phase decreases with the increase in deformation *** effect of strain rate on microstructure variables of isothermally compressed Ti555211 alloy is mainly dependent on the deformation *** fine second α phase partly transforms to β phase due to the deformation heat effect at the high strain rate,α phase becomes globular with temperature increasing and strain rate *** contrast,α phase is refined with temperature decreasing and strain rate *** deformation degree has a little influence on the grain size and the morphology of primary α phase,but the effect of deformation degree on the morphology of second α phase is *** larger deformation degree is in favor of the globularization of lamellar α structure.

关键词： Titanium alloy High-temperature deformation Micros

MULTIPLICITY-PRESERVING TRIANGULAR SET DECOMPOSITION OF TWO POLYNOMIALS

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Journal of Systems Science & Complexity 2014年第6期27卷 1320-1344页

作者： CHENG jin-San GAO Xiao-shan Key Laboratory of Mathematics Mechanization Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, a multiplicity-preserving triangular set decomposition algorithm is proposed for a system of two polynomials, which involves only computing the primitive polynomial remainder sequence of two polynomials once and certain GCD computations. The algorithm decomposes the unmixed variety defined by two polynomials into square free and disjoint （for non-vertical components, see Definition 4） algebraic cycles represented by triangular sets which may have negative multiplicities. Thus, the authors can count the multiplicities of the non-vertical components. In the bivariate case, the amthors give a complete algorithm to decompose tile system into zeros represented by triangular sets with multiplicities. The authors also analyze the complexity of the algorithm in the bivariate ease. The authors implement the algorithm and show the effectiveness of the method with extensive experiments.

关键词： Algebraic cycle multiplicity-preserving primitive polynomial remainder sequence trian-gular set decomposition.

Effect of Methanol on Photosynthesis and Chlorophyll Fluorescence of Flag Leaves of Winter Wheat

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Agricultural Sciences in China 2008年第4期7卷 432-437页

作者： ZHENG Yue-jin yang Yue-qin LIANG shan-shan YI Xian-feng College of Agriculture Henan University of Science and Technology Luoyang 471003 P.R.China

Photosynthesis and chlorophyll a fluorescence parameters, photochemical efficiency of PS II （Fv/Fm）, photochemical quenching of PS II （qP）, nonphotochemical quenching of PS II （NPQ）, maximum activity of PS II （Fv/Fo） as well as electron transport rate （ETR）, and quantum yield of PS II （ФPS II） were measured on flag leaves of the winter wheat treated by methanol at different concentrations. The results revealed that photosynthesis was greatly improved by methanol, as indicated by higher photosynthetic rates and stomatal conductance. The enhancement effect of methanol on photosynthesis was maintained for 3-4 days. Different methanol concentration treatments also increased intercellular CO2 concentration and transpiration rates. No significant decline was found in Fv/Fm, Fv/Fo, and ФPS II, which revealed no photoinhibition during methanol application in different methanol concentrations. Methanol showing no apparent inhibitory effects indicated higher potential photosynthetic capacity of flag leaves of winter wheat. However, the increase in photosynthesis was not followed by an increase in the photosynthetic activity （Fv/Fm）, and fluorescence parameters did not indicate an improvement in intercellular CO2 concentration and PS II photochemical efficiency compared with the control, thereby encouraging us to propose that lower leaf temperatures caused by applied methanol would reduce both dark respiration and photorespiration （most importantly）, thus, increasing net CO2 uptake and photosynthetic rates.

关键词： methanol photosynthetic activity chlorophyll fluorescence flag leaf winter wheat