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Approximation of the Fractional Schrodinger Propagator on Compact Manifolds

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1485-1496页

作者： Jie Cheng CHEN da Shan faN fa You ZHAO Department of Mathematics Zhejiang Normal UniversityJinhua 321000P.R.China Department of Mathematical Sciences University of Wisconsin–MilwaukeeMilwaukeeWI 53201USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

Let L be a second order positive,elliptic differential operator that is self-adjoint with respect to some C^(∞)density dx on a compact connected manifold *** proved that if 00.

关键词： Schrodinger propagator almost everywhere convergence compact manifolds

Pollen and Resource Limitation in Veratrum nigrum L. （Liliaceae）, an Andromonoecious Herb

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Journal of Integrative Plant Biology 2006年第12期48卷 1401-1408页

作者： Wan-Jin Liao Qing-fa Song da-Yong Zhang Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering and Institute of Ecology Beijing Normal University Beijing 100875 China

Pollen limitation and resource limitation were invoked to account for the pattern that flowering plants produce more flowers and ovules than fruits and seeds. This study aimed to determine their relative importance in Veratrum nigrum, a self-compatible, perennial, andromonoecious herb. In order to determine whether female production was limited by pollen grains on stigmas or by available resources, we performed supplemental hand pollination in three populations, male-flower-bud removal in three other populations, and emasculation of hermaphroditic flowers in still another population, resulting in a total of seven populations experimentally manipulated. Across the three populations, supplemental hand pollination did not significantly increase fruit set, seed number per fruit, and total seed production per individual, nor did emasculation of hermaphroditic flowers. Taken together, our results suggest that pollen grains deposited on stigmas were abundant enough to fertilize all the ovules. Male-flower-bud removal significantly increased the mean size of hermaphroditic flowers in all three populations. Female reproductive success was increased in one population, but not in the other two populations possibly due to heavy flower/seed predation. We concluded that the female reproductive success of V. nigrum was not limited by pollen grains but by available resources, which is consistent with Bateman＇s principle. Furthermore, the female reproduction increase of male-flower-bud removal individuals might suggest a trade-off between male and female sexual functions.

关键词： andromonoecy pollen limitation resource limitation trade-off Veratrum nigrum

Research on Flexural Behavior of Coral Aggregate Reinforced Concrete Beams

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China Ocean Engineering 2018年第5期32卷 593-604页

作者： MA Hai-yan da Bo YU Hong-fa WU Zhang-yu Department of Civil Engineering Nanjing University of Aeronautics and Astronautics

Through the flexural behavior test of coral aggregate reinforced concrete beams(CARCB) and ordinary Portland reinforced concrete beams(OPRCB), and based on the parameters of concrete types, concrete strength grades and reinforcement ratios, the crack development, failure mode, midspan deflection and flexural capacity were studied, the relationships of bending moment-midspan deflection, load-longitudinal tensile reinforcement strain, load-maximum crack width were established, and a calculation model for the flexural capacity of CARCB was suggested. The results showed that with the increase in the reinforcement ratio and concrete strength grade, the crack bending moment(Mcr)and ultimate bending moment(Mu) of CARCB gradually increased. The characteristics of CARCB and OPRCB are basically the same. Furthermore, through increasing the concrete strength grade and reinforcement ratio, Mcr/Mu could be increased to delay the cracking of CARCB. As the load increased, crack width(w) would also increase. At the beginning of the loading, w increased slowly. And then it increased rapidly when the load reached to the ultimate load, which then led to beam failure. Meanwhile, with a comprehensive consideration of the effects of steel corrosion on the loss of steel section and the decrease of steel yield strength, a more reasonable calculation model for the flexural capacity of CARCB was proposed.

关键词： coral aggregate reinforced concrete beam flexural behavior steel corrosion reinforcement ratio concrete strength calculation model

The Necessary and Sufficient Conditions for a Universal Conservation of a State of a Unitary Quantum Circuit

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Communications in Theoretical Physics 2002年第7期38卷 31-34页

作者： LI da-fa LI Xin-Xin HUANG Hong-Tao Department of Mathematics Tsinghua University Beijing 100084 China Department of Computer Science Wayne State University Detroit MI 48202 USA Electrical Engineering and Computer Science Department University of Michigan Ann Arbor MI 48109 USA

By A. Peres and A. Stern's opinions a computational process evolves along a cyclic logic orbit defined by a computation. A. Stern thought that if we could design such a circuit, its operations can be extended to including nonconservative behavior associated with the external perturbations or internal quantum errors. A. Peres did not discuss how to make φM-1 ＝φo. A. Stern proposed only a necessary condition for a conservation of a state of a quantum *** this paper we present a necessary and sufficient condition for a universal conservation of a state of a quantum *** also find all operators which can allow the conservation.

关键词： logic operators, matrix logic, quantum circuits

Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report

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World Journal of Clinical Cases 2025年第2期13卷 50-58页

作者： Xiu-Ying Chen fa Shen Chang Cheng Yu-Han Wang Wen-Chao Cheng De-Zhi Yuan Wen Huang Department of Neurology Chongqing Emergency Medical CenterChongqing University Central HospitalChongqing 400000China Department of Neurology Xinqiao HospitalThe Army Medical University(Third Military Medical University)Chongqing 400000China

BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic *** cerebral fat embolism(CFE)as a complication is rare,it carries serious health *** SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling *** the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided *** physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon *** clinical diagnosis was acute cerebral embolism following facial fat filling *** included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb *** patient showed a significant improvement in symptoms after 2 weeks of *** recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of *** Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial *** prevent these complications,plastic surgeons should enhance their professional knowledge and skills.

关键词： Cerebral fat embolism Mechanical thrombectomy Thrombolysis Steroid therapy Symptomatic treatment Case report

Expression of local renin and angiotensinogen mRNA in cirrhotic portal hypertensive patient

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World Journal of Gastroenterology 2003年第7期9卷 1584-1588页

作者： LiZhang ZhengYang Bao-MinShi da-PengLi Chong-Yunfang fa-ZuQiu DepartmentofGeneralSurgery ShandongProvincialHosoital.Jinan250021.ShandongProvince.China DepartmentofGeneralSurgery TongjiHospitalTongjiMedicalCollegeHuazhongScienceandTechnologyUniversity.Wuhan430030.HubeiProvince.China DepartmentofGeneralSurgery ShanghaiFirstPeople'sHospitalShanghai200080China ImmunologyInstituteofTongjiMedicalCollege HuazhongScienceandTechnologyUniversityWuhan430030HubeiProvinceChina

AIM: To investigate the expression of local renin and angiotensinogen mRNA in cirrhotic portal hypertensive ***: The expression of local renin and angiotensinogen mRNA in the liver, splenic artery and vein of PH patients was detected by RT-PCR ***: Expression of local renin mRNA in the liver of control group was (0.19±0.11), significantly lower than that in splenic artery(0.45±0.17)or splenic vein(0.39±0.12)respectively, (P＜0.05). Expression of local angiotensinogen mRNA in the liver was (0.64±0.21), significantly higher than that in splenic artery(0.41±0.15) or in splenic vein (0.35±0.18)respectively, (P＜0.05). Expression of local renin mRNA in the liver, splenic artery and vein of PH group was (0.78±0.28),(0.86±0.35) and (0.81±0.22) respectively, significantly higher than that in the control group, (P＜0.05). Expression of local angiotensinogen mRNA in the liver, splenic artery and vein of PH group was (0.96±0.25), (0.83±0.18) and (0.79±0.23)respectively, significantly higher than that in the control group,(P＜0.05). There was no significant difference between the liver, splenic artery and vein in the expression of local renin or local angiotensinogen mRNA in PH group, (P＜0.05).CONCLUSION: In normal subjects the expression of local renin and angiotensinogen mRNA was organ specific, but with increase of the expression of LRAS, the organ-specificity became lost in cirrhotic patients. LRAS may contribute to increased resistance of portal vein with liver and formation of splanchnic vasculopathy.

关键词：肝硬化高血压血管紧张肽原酶血管紧张素原 PT-PCR法

Synthesis of N-Succinyl-chitosan(Suc-Chi) and Preparation of Oxymatrine(OM)/N-Succinyl-chitosannanoparticles

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Chemical Research in Chinese Universities 2006年第5期22卷 589-592页

作者： YAN Cheng-yun CHEN da-wei GU Ji-wei LI Liu-fa School of Pharmacy Shenyang Pharmaceutical University Shenyang 110016 P. R. China College of Chemistry ＆ Pharmacy Jiamusi University Jiamusi 154000 P. R. China

Oxymatrine （OM）/N-succinyl-chitosan （Suc-Chi, with a degree of substitution being 0. 32） was synthesized via the ring-opening reaction of succinic anhydride with chitosan in dimethyl sulfoxide. OM-loaded Suc-Chi nanoparticles were prepared by an ionotropic gelation process and OM was quantified via the HPLC method： The influences of the initial OM concentration on the nanoparticle characteristics and OM release behavior were evaluated. The nanoparticles were found to have a mean diameter within a range of 267-392 nm, a positive surface charge, and a zeta potential in the range of 19-27 inV. The formulation with an initial OM concentration of 100μg/mL provided the highest loaded capacity（0. 77% ） and the highest extent of the released OM （68% at 24 h）, suggesting the possibility to achieve a therapeutic dose. According to the data obtained, this Suc-Chi-based nanotechnology will open up new and interesting prospects for the development of new anticancer drugs.

关键词： N-Succinyl-chitosan Synthesis Oxymatrine Nanoparticles Characterization

Development of Glass Ceramics Made From Ferrous Tailings and Slag in China

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Journal of Iron and Steel Research International 2007年第2期14卷 73-78页

作者： LIU Cheng-jun SHI Pei-yang ZHANG da-yong JIANG Mao-fa School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

A great amount of ferrous tailings and slag cause severe damage to the ecological environment, which must be reclaimed and utilized. The composition, type, and characteristics of ferrous tailings and slag in China were introduced. The research status and the application outlook of glass ceramics made from ferrous tailings and slag were discussed. Glass ceramics made from ferrous tailings and slag can be applied to various fields, and it will be environmentally conscious materials in the 21st century.

关键词： glass ceramics ferrous tailings slag

Necessary and Sufficient Conditions of Separability for Multipartite Pure States

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Communications in Theoretical Physics 2008年第5期49卷 1211-1216页

作者： LI da-fa LI Xiang-Rong HUANG Hong-Tao LI Xin-Xin Department of Mathematical Sciences Tsinghua University Beijing 100084 China Department of Mathematics University of California Irvine CA 92697-3875 USA Electrical Engineering and Computer Science Department University of Michigan Ann Arbor MI 48109 USA Department of Computer Science Wayne State University Detroit MI 48202 USA

In this paper we present a necessary and sufficient condition of separability for multipartite pure states and variants of it. These conditions are very simple and calculable, and they do not require Schmidt decomposition （for two subsystems） or tracing out operations. We also give a necessary condition for a local unitary equivalence class for a bipartite system in terms of the determinant of the matrix of amplitudes.

关键词： entanglement quantum computing separability