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Science China Mathematics 2011年第6期54卷 1225-1232页

作者： zhu sen JI YouQing Department of Mathematics Jilin University Changchun 130012 China

Let B(H) be the algebra of all bounded linear operators on a complex separable infinite dimensional Hilbert space *** by π the quotient map of B(H) onto the Calkin algebra A(H).In 1984,Apostol et *** the following conjecture:If an operator T on H is not similar to a compact perturbation of a Jordan operator,then the similarity orbit of π(T) in A(H) coincides with the π-image of the similarity orbit of *** this paper,we investigate the structure of similarity orbits in the Calkin algebra and give a negative answer to the above conjecture.

关键词： Calkin algebra similarity similarity orbits compact operators

Numerical simulation of flow separation over a backward-facing step with high Reynolds number

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Water Science and Engineering 2019年第2期12卷 145-154页

作者： Fang-fang Wang Shi-qiang Wu sen-lin zhu State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute

Large eddy simulation (LES) explicitly calculates the large-scale vortex field and parameterizes the small-scale *** this study,LES and κ-ε models were developed for a specific geometrical configuration of backward-facing step (BFS).The simulation results were validated with particle image velocimetry (PIV) measurements and direct numerical simulation (DNS).This LES simulation was carried out with a Reynolds number of 9000 in a pressurized water tunnel with an expansion ratio of *** results indicate that the LES model can reveal largescale vortex motion although with a larger grid-cell ***,the LES model tends to overestimate the top wall separation and the Reynolds stress components for the BFS flow simulation without a sufficiently fine ***,LES is a potential tool for simulating separated flow controlled by large-scale vortices.

关键词： Large eddy simulation κ-ε model Backward-facing step Direct numerical simulation Large-scale vortices Particle image velocimetry

Clinical analysis of bone scanning in solitary lesion

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Nuclear Science and Techniques 2002年第2期13卷 72-78页

作者： zhu Jun, zhu Rui-sen, zhu Ji-Fang (The 6th People’s Hospital, Shanghai 200233) Shanghai The 6th People's Hospital 上海 200233

A rational analysis procedure for solitary lesions on whole bone scan-ning was offered. This study was undertaken to analyze retrospectively solitary le-sions which obtained final diagnose through the following aspects: (1) diagnosis ofbone metastasis, (2) the incidence of bone metastasis in different tumor, (3) the mostpossible lesion sites indicating bone metastasis, (4) morphological analysis of solitarylesions. The results are: (1) The incidence of solitary lesions in 2465 cases on wholebone scanning is 15.3%. (2) The rate of bone metastasis is 24.8% in 282 patientswith primary malignancy. The rate of bone metastasis is 6.3% in 64 patients withoutprimary malignancy, and the total diagnostic rate of bone metastasis is 21.4% in 346patients. (3) In patients with primary malignancy, the incidence of bone metastasis ofsolitary lesions is as follows respectively: bronchi cancer 36.1%(22/61); breast cancer23.8%(20/84); prostate gland 17.2%(5/29); other urinary system cancer 22.2%(4/18):G.I. system cancer 16.9%(10/59); others 29.0%(9/31). There is no significant differ-ence in different cancer. (4) In patients without primary malignancy, 93.7%(60/64) ofsolitary lesions are benign. (5) From anatomical point of view, we found the diagnos-tic rate of bone metastasis is as follow: 30% in spine; 34.2% in pelvis; 36.4% in skull;10.8% in other bones. There are significant differences in four groups. It is concludedthat: (1) The diagnostic rate of bone metastasis in solitary lesions is 21.4%. (2) Themost possible solitary lesions indicating osseous tumor spread are at spine, pelvic andskull. (3) Special attention to "cold" and streak like lesions should be paid. (4) Aclinical analysis procedure for diagnosis of solitary lesions has been summarized outhere.

关键词：骨瘤临床分析辐射造影

B lymphoma Moloney murine leukemia virus insertion region 1: An oncogenic mediator in prostate cancer

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Asian Journal of Andrology 2019年第3期21卷 224-232页

作者： Qipeng Liu Qiaqia Li sen zhu Yang Yi Qi Cao Center for Inflammation and Epigenetics Houston Methodist Research Institute Houston TX 77030 USA Xiangya School of Medicine Central South University Changsha 410008 China Key Laboratory for Stem Cells and Tissue Engineering Ministry of Education Sun Yat-Sen University Guangzhou 510080 China Department of Histology and Embryology Zhongshan School of Medicine Sun Yat-Sen University Guangzhou 510080 China Houston Methodist Cancer Center Houston Methodist Research Institute Houston TX 77030 USA Department of Microbiology and Immunology Weill Cornell Medicine Cornell University New York NY 10065 USA

B lymphoma Moloney murine leukemia virus insertion region 1 (BMI1), a core member of polycomb repressive complex 1 (PRC1), has been intensely investigated in the field of cancer epigenetics for decades. Widely known as a critical regulator in cellular physiology, BMI1 is essential in self-renewal and differentiation in different lineages of stem cells. BMI1 also plays a significant role in cancer etiology for its involvement in pathological progress such as epithelial–mesenchymal transition (EMT) and cancer stem cell maintenance, propagation, and differentiation. Importantly, overexpression of BMI1 is predictive for drug resistance, tumor recurrence, and eventual therapy failure of various cancer subtypes, which renders the pharmacological targeting at BMI1 as a novel and promising therapeutic approach. The study on prostate cancer, a prevalent hormone-related cancer among men, has promoted enormous research advancements in cancer genetics and epigenetics. This review summarizes the role of BMI1 as an oncogenic and epigenetic regulator in tumor initiation, progression, and relapse of prostate cancer.

关键词： B lymphoma Moloney murine leukemia virus insertion region 1 oncogene polycomb repressive complex 1 prostate cancer

A numerical study of hydrodynamic characteristics and hydrological processes in the coastal wetlands during extreme events

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Journal of Hydrodynamics 2023年第5期35卷 963-979页

作者： Ming-liang Zhang Xiao-sen zhu Yu-jia Wang Heng-zhi Jiang Lei Cui College of Ocean Science and Environment Dalian Ocean UniversityDalian116023China Technology Innovation Center for Coastal Ecological Environment and Disaster Protection Liaoning ProvinceDalian116023China National Marine Environmental Monitoring Center Dalian116023China

Providing accurate predictions of extreme water levels through numerical simulation has become essential for disaster prevention and damage mitigation in coastal wetland *** study applies the FVCOM model to simulate storm surges caused by several typhoons in the Bohai Sea and the North Huanghai *** vegetation drag force caused by salt marsh plants is inserted into the FVCOM model for model improvement with vegetation effect by integrating RS and GIS technologies.A parametric typhoon model is coupled with background wind fields derived to acquire the spatio-temporal variations of wind and pressure fields in the computational *** simulation results reproduce the extreme storm surges induced by typhoon events very *** modeling results are compared by validating with literature results to examine the effect of vegetation on tidal waves in tidal mud ***,the coupled model is also applied to explore storm surge attenuation and land intrusion during Typhoon Winnie in the wetlands of the Liao River *** simulation results indicate that salt marsh plants can reduce the flow current with little impact on tide flooding/ebbing in vegetated ***,the results show that typhoon presence increases the inundation depth and extendes the flood time in the tidal wetlands of the study *** FVCOM model incorporating the method with vegetation drag force can provide new insights to understand the comprehensive impact of tidal wetland plants on hydrodynamic characteristics in the Bohai Sea and other waters,hence presents a more accurate quantification of the hydrological process of storm surge in the tidal wetlands.

关键词： FVCOM circulation model Parametric typhoon model coastal wetlands storm surge hydrological process

OsMYB103 is required for rice anther development by regulating tapetum development and exine formation

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Chinese Science Bulletin 2010年第29期55卷 3288-3297页

作者： ZHANG sen FANG ZiJun zhu Jun GAO JuFang YANG ZhongNan College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 China

The Arabidopsis AtMYB103 gene is required for anther development,but whether the homologous gene in rice has the same role is *** analysis indicated that the rice OsMYB103 gene shares a high sequence similarity with ***,we investigated the functional role of OsMYB103 in anther development using an RNAi *** OsMYB103 RNA transcript was expressed most abundantly in flowers,specifically in the tapetum,premeiotic pollen mother cells,and meiotic ***103-RNAi transgenic lines grew normally during their vegetative phase but displayed reduced male fertility,a phenotype that was associated with downregulated OsMYB103 transcript *** of OsMS2,an ortholog of the Arabidopsis AtMS2 gene,was also dramatically reduced in the transgenic *** of OsMYB103 led to defects in tapetum development,and most of the microspores in mature anthers lacked ***,OsMYB103 could partially rescue the male sterility phenotype of an AtMYB103 knockout mutant *** together,these results indicate that OsMYB103 does have an important role in rice tapetum and microspore development.

关键词：花药绒毡层水稻 RNA干扰转基因植株同源基因外壁转录水平序列相似性

Morphology, size and distribution of MnS inclusions in non-quenched and tempered steel during heat treatment

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 483-491页

作者： Xiao-jing Shao Xin-hua Wang Chen-xi Ji Hai-bo Li Yang Cui Guo-sen zhu Shougang Research Institute of Technology School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

This article reports the morphology, size, and distribution evolution of MnS inclusions in non-quenched and tempered steel during heat treatment. The variation of single large-sized MnS inclusions at high temperature was observed in situ using a confocal scanning laser microscope （CSLM）. The slender MnS inclusions first changed to pearl-like slrings. These small-sized pearls subsequently coalesced and became closer together as the temperature increased. Large-sized MnS inclusions in non-quenched and tempered steel samples with different thermal histories were investigated with respect to the evolution of their morphology, size, and distribution. After 30 min of ovulation at 1573 K, the percentage of MnS inclusions larger than 3 μm decreased from 50.5% to 3.0%. After a 3 h making period, Ostwald ripening occurred. Most MnS inclusions moved from the grain bounda- ries to the interior. The present study demonstrates that heat treatment is an effective method of changing the morphology, size, and distribution of MnS inclusions, especially large-sized ones.

关键词： steel heat treatment inclusions manganese sulfide morphology size distribution

Decarburization rate of RH refining for ultra low carbon steel

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 22-27页

作者： Bai-song Liu Guo-sen zhu Huan-xi Li Ben-hai Li Yang cui Ai-min Cui School of Material Science and Engineering Beihang University Beijing 100191 China Shougang Research Institute of Technology Beijing 100041 China Qian＇an Iron and Steel Company Qian＇an 064404 China

The decarburization behaviors of ultra low carbon steel in a 210-t RH vacuum degasser were investigated under practical operat- ing conditions. According to the apparent decarburization rate constant （Kc） calculated by the carbon content in the samples taken from the hot melt in a ladle at an interval of 1-2 min, it is observed that the total decarburization reaction period in RH can be divided into the quick decarburization period and the stagnant decarburization period, which is quite different from the traditional one with three stages. In this study, the average apparent decarburization rate constant during the quick decarburization period is 0.306 min^-1, and that of the stagnant period is 0.072 min^-1. Increasing the initial carbon content and enhancing the exhausting capacity can increase the apparent decarburization rate constant in the quick decarburization period. The decarburization reaction comes into the stagnant decarburization period when the carbon content in molten steel is less than 14× 10^-6 after 10 min of decarburization.

关键词： refining decarburization ultra low carbon steel degassing

Microstructures and mechanical properties of C-Mn-Cr-Nb and C-Mn-Si-Nb ultra-high strength dual-phase steels

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 915-922页

作者： Zhi-gang Wang A i-min Zhao Zheng-zhi Zhao Jie-yun Ye Di Tang Guo-sen zhu Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China Shougang Research Institute of Technology Beijing 100039 China

The microstructures and mechanical properties of C-Mn-Cr-Nb and C-Mn-Si-Nb ultra-high strength dual-phase steels were studied by scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and tensile test. The results show that Si can promote the transformation of austenite （γ） to ferrite （α）, enlarge the （α＋γ） region, and increase the aging stability of martensite by inhibiting carbide precipitation. Adding Cr leads to the formation of retained austenite and martensite/austenite （M/A） constituents, as well as the decomposi- tion of martensite during the overaging stage. Both of the steels show higher initial strain-hardening rates and two-stage strain-hardening characteristics. The C-Mn-Si-Nb steel shows the higher strain-hardening rate than the C-Mn-Cr-Nb steel in the first stage; however, there is no significant difference in the second stage. Although the tensile strength and elongation of the two steels both exceed 1000 MPa and 15%, respectively, the comprehensive mechanical properties of the C-Mn-Si-Nb steel are superior.

关键词： high strength steel dual-phase steel alloying elements microstructure mechanical properties sWain hardening