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Some Properties of Aut_*(X) and the Subgroup Aut_Σ(X)

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Communications in Mathematical Research 2009年第2期25卷 97-103页

作者： QIAN YOU-hua chen SHENG-min College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua Zhejiang 321004

Let Aut. （X） denote the group of homotopy classes of self-homotopy equivalences of X, which induce identity automorphisms of homology group. We describe a decomposition of Aut. （X1 V…VXn） as a product of its simpler subgroups. We consider the subgroup Aut∑（X） of all self homotopy classes α of X such that ∑α=1∑X： ∑X → ∑X, and also give some properties of Aut∑（X）.

关键词： self-homotopy equivalences the wedge space reducible

Identification of differentially-expressed genes of rice in overlapping responses to bacterial infection by Xanthomonas oryzae *** and nitrogen deficiency

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Journal of Integrative Agriculture 2015年第5期14卷 888-899页

作者： YU Chao chen hua-min TIAN Fang BI Yong-mei Rothstein J Steven Leach E Jan HE chen-yang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural Sciences Department of Molecular and Cellular Biology College of Biological ScienceUniversity of Guelph Department of Bioagricultural Sciences and Pest Management Colorado State University

Bacterial blight of rice caused by Xanthomonas oryzae ***（Xoo） is one of high nitrogen（N） responsive *** plants became more disease resistant with decreasing N suggesting that the crosstalk between disease resistance and N utilization pathways might ***,the co-regulatory components in such crosstalk have not been ***,we comparatively analyzed the gene expression profiling of rice under Xoo inoculation,low N treatment,or a combination of both stresses,and identified the differentially-expressed genes（DEGs） in overlapping *** DEGs were involved in different biological processes,including innate immunity and nitrogen *** randomly-selected DEGs expression was validated by quantitative real-time PCR *** expression of six genes from different functional categories suggested that N condition was the dominant factor when both stresses were *** DEGs identified provide novel insights into the coordinated regulatory mechanism in biotic and abiotic stress responses in rice.

关键词： Xanthomonas differentially overlapping abiotic blight responsive crosstalk pathogen encoding validated

New Insights on Gamma-Ray Burst Radiation Mechanisms from Multiwavelength Observations

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Research in Astronomy and Astrophysics 2025年第2期25卷 3-12页

作者： Yu-hua Yao Fang-Sheng min Shi chen Yi-Qing Guo College of Physics Chongqing University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Wisconsin Ice Cube Particle Astrophysics Center University of Wisconsin–Madison University of Chinese Academy of Sciences School of Physics and Astronomy Yunnan University Tianfu Cosmic Ray Research Center

The study of high-energy gamma-ray emission from gamma-ray bursts(GRBs) involves complex synchrotron radiation and synchrotron self-Compton(SSC) scattering mechanisms with multiple parameters exhibiting a wide distribution. Recent advancements in GRB research, particularly the observation of very high energy(VHE,>100 Ge V) radiation, have ushered in a new era of multiwavelength exploration, offering fresh perspectives and limitations for understanding GRB radiation mechanisms. This study aimed to leverage VHE observations to refine constraints on synchrotron + SSC radiation from electrons accelerated by forward shocks. By analyzing two external environments—the uniform interstellar medium and stratified stellar wind medium, we conducted spectral and variability fitting for five specific bursts(GRB 180720B, GRB 190114C, GRB 190829A, GRB 201216C, and GRB 221009A) to identify the optimal parameters characterizing these events. A comparative analysis of model parameter distributions with and without VHE radiation observations reveals that the magnetic energy equipartition factor εBis more concentrated with VHE emissions. This suggests that VHE emissions may offer greater constraints on this microphysical parameter. Additionally, we found that the energy budget between VHE and ke V–Me V γ-ray emissions under the SSC radiation exhibits an almost linear relationship, which may serve as a tool to differentiate radiation mechanisms. We anticipate future statistical analyses of additional VHE bursts to validate our findings.

关键词： (transients:) gamma-ray bursts gamma-rays: ISM radiation mechanisms: non-thermal

High mechanical index post-contrast ultrasonography improves tissue structural display of hepatocellular carcinoma

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Chinese Medical Journal 2005年第24期118卷 2046-2051页

作者： chen min-hua YANG Wei DAI Ying WU Wei Department of Ultrasound Peking University School of OncologyBeijing 100036 China

Background The advent of second generation agent-SonoVue and low mechanical index real-time contrast enhanced ultrasonography （CEUS） imaging have been shown to improve the diagnostic performance of uhrasonography in hepatocellular carcinoma （HCC）. But no report has described the effect of high mechanical index （MI） post-CEUS. This study aimed to investigate the value of post-CEUS in displaying tissue structures of HCC. Methods Seventy-six HCCs in 65 patients were included in the study. Each patient underwent three scans, high-MI （ MI ： 0. 15 - 1.6 ） pre-contrast ultrasound, low-MI （ MI ： 0. 04 - 0. 08 ） CEUS with contrast agent SonoVue, and high-MI post-contrast ultrasound, which was performed within 3 minutes after CEUS. The size, boundary, echogenicity, internal echotexture and posterior acoustic enhancement of the HCCs in the conventional scans before and after CEUS were evaluated. According to pathological evidence, diagnosis rates of pre-contrast, CEUS and post-contrast scans were determined and compared. The potential mechanism of post-contrast ultrasound imaging was also discussed. Results Compared with pre-contrast, post-contrast ultrasound showed improvement in image quality in most HCCs： twenty-six （34. 2% ） more lesions showed well defined margins and fourteen （18.4%） more nodules showed halo sign; twenty-three （30. 3% ） lesions demonstrated enlarged in sizes; changes in echogenicity were seen in 30 lesions （39.5%） ; eighteen （23.7%） more lesions showed heterogenecity and 20 （26. 3% ） more lesions showed “mosaic”or “nodule-in-nodule” sign; twelve （15.8%） more lesions showed posterior acoustic enhancement. Post-contrast ultrasound showed increased diagnostic accuracy of 93.4% （71/76）, compare with 88.2% （67/76） of CEUS alone. Conclusions High-MI post-contrast ultrasound utilizes harmonic signals during the rupture of microbubbles, and significantly improves the display of echo-characteristics of HCCs in ultrasound images, which adds diagnostic values

关键词： ultrasonography contrast enhanced ultrasound liver neoplasm tissue structure

Role of contrast enhanced ultrasound in detection of abdominal aortic abnormalities in comparison with multislice computed tomography

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Chinese Medical Journal 2009年第7期122卷 858-864页

作者： Dirk-André Clevert Kerstin Schick chen min-hua ZHU Qing-li Maximilian Reiser Department of Clinical Radiology Klinikum Grosshaderhl University of Munich - Grosshadern Campus Marchioninistr. 15 81377 Munich Germany Department of Surgery Klinikum Grosshaderhl University of Munich - Grosshadern Campus Marchioninistr. 15 81377 Munich Germany Department of Ultrasonography Beijing Cancer Hospital PekingUniversity School of Oncology Beijing Institute for CancerResearch Beijing 100036 China Department of Ultrasonography Peking Union Medical CollegeHospital Chinese Academy of Medical Sciences & Peking UnionMedical College Beijing 100730 China

Conventional ultrasound （US） is the most widely used imaging modality in routine clinical practice worldwide. The limitations of conventional ultrasound in the detection of aortic lesions versus multi-slice compute... 详细信息

关键词： contrast enhanced ultrasound multislice computed tomography abdominal aortic lesions aorticdissection abdominal aortic aneurysm aorto-caval fistula inflammatory abdominal aortic aneurysm

Contrast-enhanced ultrasound of hepatocarcinogenesis in liver cirrhosis

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Chinese Medical Journal 2012年第17期125卷 3104-3109页

作者： WU Wei chen min-hua SUN Maryellen YAN Kun YANG Wei LI Ji-you Key laboratory of Carcinogenesis and Translational Research (ministry of Education) Department of Ultrasound Peking University Cancer Hospital & Institute Beijing 100142 China Abdominal Imaging Department of Radiology Beth Israel Deaconess Medical Center Boston 02215 USA Key laboratory of Carcinogenesis and Translational Research (ministry of Education) Department of Pathology Peking University Cancer Hospital & Institute Beijing 100142 China

Backoround Hepatocellular carcinoma （HCC） often occurs in association with liver cirrhosis. A stepwise carcinogenesis for HCC has been proposed. The purpose of this study was to observe the enhancement pattern of hepatocellular nodules in cirrhotic patients using contrast-enhanced ultrasound （CEUS） and to correlate patterns of enhancement at CEUS with the diagnosis of hepatocellular nodules using pathologic correlation as the gold standard. Methods Ninety-three cirrhotic patients with indeterminate hepatocellular nodules at ultrasound, underwent biopsy of each indeterminate nodule. Patients with nodules found to have pathologic diagnoses of regenerative nodules （RNs）, dysplastic nodules （DNs）, or DNs with focus of HCC （DN-HCC）, were enrolled in this study. Enhancement patterns of all nodules were examined throughout the various vascular phases of CEUS and classified into five enhancement patterns： type I, isoenhancement to hepatic parenchyma at all phases; type II, hypoenhancement in the arterial phase, and isoenhancement in the portal venous phase and late phase; type III, iso-to-hypoenhancement in arterial and portal venous phase, and hypoenhancement in the late phase （washout）; type IV, slight hyperenhancement in the arterial and portal venous phase and hypoenhancement in the late phase （washout）; and type V, partial hyperenhancement in the arterial phase and hypoenhancement in the late phase; and another partial iso-to-hypoenhancement in the arterial and portal venous phase and hypoenhancement in the late phase （washout）. The correlation between the contrast enhancement patterns and the pathological diagnoses was analyzed by the chi-squared test. Results Totally 132 lesions were examined with CEUS in 93 patients. Pathologic diagnoses included 45 DN, 68 RN, and 19 DN-HCC. The enhancement patterns observed were as follows： type I, 49 （37.1%）; type II, 27 （20.5%）; type III, 28 （21.2%）; type IV, 9 （6.8%）; type V, 19 （14.4%）. Nodules with type I enhancement showed dy

关键词： ultrasonography contrast agent cirrhosis hepatocellular carcinoma

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共振散射光谱法测定环境水样中微量铬Ⅵ

冶金分析 2007年第3期27卷 45-47页

作者：李娜钱保华陈敏华淮海工学院化学工程系江苏连云港222005 淮海工学院化学工程系

研究了在硫酸介质中,铬Ⅵ与碘化物和淀粉形成离子缔合物的共振光散射增强现象,拟定了一种新的测定铬Ⅵ的共振散射方法,确定了实验的最佳测定条件。采用732型强酸性离子交换树脂,可以较好地消除共存离子的干扰。在λex=λem=290nm处,缔... 详细信息

研究了在硫酸介质中,铬Ⅵ与碘化物和淀粉形成离子缔合物的共振光散射增强现象,拟定了一种新的测定铬Ⅵ的共振散射方法,确定了实验的最佳测定条件。采用732型强酸性离子交换树脂,可以较好地消除共存离子的干扰。在λex=λem=290nm处,缔合物共振光散射最强,且共振光散射强度与铬(的质量浓度呈线性关系,线性范围为22·3～400μg/L,检出限为6·7μg/L。该方法简便、快速,用于环境水样中铬的测定,相对标准偏差≤0·51%,加标回收率为91%～116%。

关键词：铬Ⅵ 共振散射淀粉碘化钾

Value of frozen section examination in diagnosis and treatment of high-grade cervical intraepithelial neoplasia

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Chinese Medical Journal 2012年第14期125卷 2462-2465页

作者： REN Fang FENG Wei SHI Hui-rong WU Qing-hua chen Zhi-min Department of Obstetrics and Gynecology First Affiliated Hospitalof Zhengzhou University Zhengzhou Henan 450052 China

Background Invasive cancer of the cervix is considered a preventable disease because it has a long pre-invasive state, cervical cytology screening programs are currently available, and treatment of pre-invasive lesions is effective. We tested the accuracy of frozen section examination （FSE） of cone specimens to identify the endocervical margin and rule out invasion in patients with high-grade cervical intraepithelial neoplasia （CIN）. Methods For 320 consecutive patients with a preoperative biopsy result of CIN stage 2/3, cold-knife conization （CKC） was performed followed by FSE. The results from analyses of permanent paraffin sections （PS） were compared with the FSE findings. Results The accuracy of FSE was 87% （278/320）. For all of the seven patients with an invasive squamous cell carcinoma of the cervix identified by FSE, the diagnosis was confirmed by PS analysis. For one patient, the FSE result was cervicitis, whereas PS ananlysis showed microinvasive carcinoma. Appropriate surgery was performed for all patients based on the FSE and biopsy results. The FSE and PS results were not significantly different （P=-0.000）. Definitive examination of margin status using PS was concordant with FSE findings in all cases. Conclusions FSE is a rapid and reliable method for evaluating CKC specimens. It can identify frank invasion, permit adequate treatment in a one-stage procedure, and reliably detect clear resection margins. Since discrepancies do exist and may result in inappropriate treatment, further research is required to decrease these discrepancies and avoid missing even one case.

关键词： cervical intraepithelial neoplasia frozen section examination cold-knife conization, the upper endocervical margin, resection margin

Soil colloids can significantly enhance spreading of polybromodiphenyl ethers in groundwater by serving as an effective carrier

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Journal of Environmental Sciences 2025年第1期147卷 93-100页

作者： Lin Duan min Li Jiameng Liu Wei chen College of Environmental Science and Engineering Ministry of Education Key Laboratory of Pollution Processes and Environmental CriteriaTianjin Key Laboratory of Environmental Remediation and Pollution ControlNankai UniversityTianjin 300350China

Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling *** association of PBDEs with soil colloids has been observed,indicating the potential risk to groundwater due to colloid-facilitated ***,the extent to which soil colloidsmay enhance the spreading of PBDEs in groundwater is largely ***,we report the co-transport of decabromodiphenyl ester(BDE-209)and soil colloids in saturated porous *** colloids released froma soil sample collected at an e-waste recycling site in Tianjin,China,contain high concentration of PBDEs,with BDE-209 being the most abundant conger(320±30 mg/kg).The colloids exhibit relatively high mobility in saturated sand columns,under conditions commonly observed in groundwater ***,under all the tested conditions(i.e.,varying flow velocity,pH,ionic species and ionic strength),the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids,even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions ***,the mass of BDE-209 retained in the columns also correlates strongly with themass of retained ***,the PBDEs remain bound to soil colloids during transport in porous *** in this study indicate that soil colloidsmay significantly promote the transport of PBDEs in groundwater by serving as an effective *** might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites.

关键词： Polybromodiphenyl ethers Soil colloids E-waste recycling sites Groundwater Facilitated transport