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Oscillation for a Class of Diffusive Hematopoiesis Model with Several Arguments

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2345-2354页

作者： Xiao WANG Hao ZHANG zhi xiang li Department of Mathematics and System Science College of ScienceNational University of Defense Technology

By considering solution curve＇s or surface＇s composition of the functions of several variables and constructing the suitable lower-upper solution pair for the following special diffusive Hematopoiesis modelunder Neumann boundary condition, sufficient conditions are provided for the oscillation of the positive equilibrium for （0.1）. Moreover, these results extend or complement existing results.

关键词： Partial functional differential equations lower-upper solution pair oscillation

Impulsive Boundary Value Problems for First-order Ordinary Differential Inclusions

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 411-420页

作者： Yi-cheng liu Jun Wu zhi-xiang li Department of Mathematics and System Science College of Science National University of Defense TechnologyChangsha 410073 China College of Mathematics and Computer Science Changsha University of Science Technology Changsha 410076China

In this paper, we investigate the existence of solutions for impulsive first order ordinary differential inclusions which admitting nonconvex valued right hand side. We present two classes of results. In the first one, we rely on a fixed point theorem for contraction multivalued maps due to Covitz and Nadler, and for the second one, we use Schacfer＇s fixed point theorem combined with lower semi-continuous multivalued operators with decomposable values under weaker conditions.

关键词： Impulsive differential inclusions measurable selection contraction multi-valued map boundaryvalue problems

Replicated Banded Spherulite:Microscopic Lamellar-assembly of Poly(L-lactic acid)Crystals in the Poly(oxymethylene)Crystal Framework

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Chinese Journal of Polymer Science 2018年第3期36卷 385-390页

作者： li-Jun Ye Jie-Qing Shen Kang-Yuan Xie zhi-xiang li Yong-Jin li College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 310036China

The morphologies of poly(L-lactic acid)(PLLA)spherulites,when crystallized within the pre-existed poly(oxymethylene)(POM)crystal frameworks,have been ***/POM blend is a melt-miscible crystalline/crystalline blend *** to the lower melting point but much faster crystallization rate than PLEA,POM crystallized first upon cooling from the melt state and then melted first during the subsequent heating process in this blend *** assembly of PLLA crystals within the pre-existed POM spherulitic frameworks was directly observed with the polarized light microscopy by selectively melting the POM *** investigation indicated that PLLA crystals fully replicated the spherulitic morphology and optical birefringence of the POM crystal frameworks,which was independent of T_(o).On the other hand,POM could also duplicate the pre-existed PLLA *** result obtained provides us a possibility to design the lamellar assembly and crystal structures of polymer crystals in miscible crystalline/crystalline polymer blends.

关键词： Banded spherulite Lamellar assembly Confinement Poly(L-lactic acid) Poly(oxymethylene)

Effects of surface roughness on overflow discharge of embankment weirs

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Journal of Hydrodynamics 2021年第4期33卷 773-781页

作者： Shang-tuo Qian Yan Zhang Hui Xu Xiao-sheng Wang Jian-gang Feng zhi-xiang li College of Agricultural Science and Engineering Hohai UniversityNanjing210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Power China Huadong Engineering Corporation limited Hangzhou311122China

A numerical study was performed on the embankment weir overflows with various surface roughness and tailwater submergence, to better understand the effects of weir roughness on discharge performances under the free and submerged conditions. The variation of flow regime is captured, from the free overflow, submerged hydraulic jump, to surface flow with increasing tailwater depth. A roughness factor is introduced to reflect the reduction in discharge caused by weir roughness. The roughness factor decreases with the roughness height, and it also depends on the tailwater depth, highlighting various relations of the roughness factor with the roughness height between different flow regimes, which is linear for the free overflow and submerged hydraulic jump while exponential for the surface flow. Accordingly, the effects of weir roughness on overflow discharge appear nonnegligible for the significant roughness height and the surface flow regime occurring under considerable tailwater submergence. The established empirical expressions of discharge coefficient and submergence and roughness factors make it possible to predict the discharge over embankment weirs considering both tailwater submergence and surface roughness.

关键词： Discharge embankment weir numerical simulation tailwater submergence surface roughness

Standardizing R-E-NSM Surgical Protocols: A Critical Appraisal for Breast Cancer Patients

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Current Medical Science 2024年第5期44卷 1066-1067页

作者： Wen-qin WANG xiang-zhi li Yong-mei WANG School of life Sciences Shandong University(Qingdao)Qingdao266237China Breast Disease Center The Affiliated Hospital of Qingdao UniversityQingdao266071China

To the editors:We read with interest the article by Jiao ZHOU et al,which introduces a novel technique of reverse-sequence endoscopic nipple-sparing mastectomy(R-E-NSM)with direct-to-implant breast reconstruction(DIBR)for breast cancer *** the study presents a promising approach,the interpretation of its findings warrants careful consideration owing to several methodological and clinical aspects:(1)Table 1 presents the lymph node status following propensity score matching but does not detail the total number of lymph nodes resected.

关键词： Breast Surgical Cancer

Research advances in the study of Pistacia chinensis Bunge, a superior tree species for biomass energy

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Forestry Studies in China 2007年第2期9卷 164-168页

作者： li Hong-lin Zhang zhi-xiang lin Shan-zhi li Xiao-xu College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 P. R. China

As a renewable energy, biomass energy has aroused wide attention and studies of this issue have become a hot topic throughout the world. Pistacia chinensis Bunge （Anacardiaceae） is a superior species for biomass energy with high oil content in seeds and wide geographic distribution. It is a dioeciously, deciduous arbor, flowering from March to April and bearing fruits from September to November. The classification, regional distribution and biological characteristics ofP chinensis are stated in this paper, then, research advances in the growth, breeding and physiology of this species are summarized. The problems in present studies are broached. Finally, a future direction for research is proposed.

关键词： Pistacia chinensis Bunge biomass energy of forest

Asymmetric synthesis of pedamide using I_2-induced heterocyclization to construct the skeleton

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Chinese Chemical Letters 2009年第7期20卷 775-778页

作者： De Gang liu Ji Jun Xue zhi xiang Xie li Ping Wei Hua Bing Zhang Ying li State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 PR China

An alternative approach to synthesize pedamide, a key building block of pederin was described. Iodine-induced asymmetric heterocyclization was used as the key step to construct the skeleton, a tetrahydropyran ring with three chiral centers. Brown＇s asymmetric allylation and Lewis acid-mediated allylation were investigated to introduce chains and chiral alcohols. Sharpless dihydroxylation decorated the side chain. And high optically pure target was obtained by removing the epimers formed in these reactions on column chromatography.C2009 Ji Jun Xue. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Synthesis Pedamide Pederin

Diagnostic and prognostic role of liNC01767 in hepatocellular carcinoma

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World Journal of Hepatology 2024年第6期16卷 932-950页

作者： li Zhang Tong-Xing Cui xiang-zhi li Chong liu Wen-Qin Wang Department of Thyroid and Breast Surgery The Affiliated People Hospital of Second Medical UniversityWeifang 266010Shandong ProvinceChina Department of General Surgery Qingdao Municipal Hospital GroupQingdao 266237Shandong ProvinceChina School of life Sciences Shandong University(Qingdao)Qingdao 26637Shandong ProvinceChina School of Medicine Tsinghua UniversityBeijing 100084China

BACKGROUND Hepatocellular carcinoma(HCC)is a primary contributor to cancer-related mortality on a global ***,the underlying molecular mechanisms are still poorly *** noncoding RNAs are emerging markers for HCC diagnosis,prognosis,and therapeutic *** study of liNC01767 in HCC was *** To conduct a multi-omics analysis to explore the roles of liNC01767 in HCC for the first *** DESeq2 Package was used to analyze different gene *** operating characteristic curves assessed the diagnostic ***-Meier univariate and Cox multivariate analyses were used to perform survival *** least absolute shrinkage and selection operator(LASSO)-Cox was used to identify the prediction *** to the validation of liNC01767 expression in HCC fresh frozen tissues through quantitative real time polymerase chain reaction,next generation sequencing was performed following liNC01767 over expression(GSE243371),and Gene Ontology/Kyoto Encyclopedia of Genes and Genomes/Gene Set Enrichment Analysis/ingenuity pathway analysis was carried *** vitro experiment in Huh7 cell was carried *** liNC01767 was down-regulated in HCC with a log fold change=1.575 and was positively correlated with the cancer ***01767 was a good diagnostic marker with area under the curve(AUC)[0.801,95% confidence interval(CI):0.751-0.852,P=0.0106]and an independent predictor for overall survival(OS)with hazard ratio=1.899(95%CI:1.01-3.58,P=0.048).liNC01767 nomogram model showed a satisfied *** top-ranked regulatory network analysis of liNC01767 showed the regulation of genes participating various *** regression identified the 9-genes model showing a more satisfied performance than 5-genes model to predict the OS with AUC>***01767 was down-expressed obviously in tumor than para-tumor tissues in our cohort as well as in cancer cell line;the over expression of liNC01767 inhibit cell prolifer

关键词： Hepatocellular carcinoma liNC01767 Multi-omics analysis GSE243371 Cell proliferation Clone formation

Influence of vibration on granular flowability and its mechanism of aided flow

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Journal of Central South University of Technology 2001年第4期8卷 252-257页

作者： WU Ai xiang,SUN Ye zhi,li Jian hua (College of Resources, Environment and Civil Engineering, Central South University, Changsha 410083, China) 1. College of Resources Environment and Civil Engineering Central South University 410083 Changsha China

Regarding flowing granular media as weak transverse isotropic media, the phase velocity expressions of wave P, wave SH and wave SV were deduced, the propagation characteristics of waves in flowing granular media were analyzed. The experiments show that vibration has great influence on granular fluidity. The wavefront of wave P is elliptic or closely elliptic, the wavefront of wave SH is elliptic, and the wavefront of wave SV is not elliptic. Wave propagation in the granular flowing field attenuates layer after layer. The theory and experiment both substantiate that the density difference is the key factor which leads to the attenuation of vibrating energy. In terms of characteristics of wave propagation one can deduce that vibrating waves have less influence on flowability of granules when the amplitude and frequency are small. However, when the amplitude and frequency increase gradually, the eccentricity of ellipsoid, the viscosity resistance and inner friction among granules, and shear intensity of granules decrease, and the loosening coefficient of granules increases, which shows the granules have better flowability.

关键词： granular media vibrating aided flow body wave mechanism