68 results on '"X. H. Du"'
Search Results
2. Oblique Incidence of Seismic Wave Reflecting Two Components of Design Ground Motion
- Author
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W. J. Cen, X. H. Du, D. J. Li, and L. N. Yuan
- Subjects
Physics ,QC1-999 - Abstract
The wave field on the artificial boundary was separated into the free field without local topography effect and scattering field induced by local topography effect. The simulation of the free field under obliquely incident waves was conducted. Based on the assumption that the components of design ground motion were treated as the coincidence of oblique P wave and oblique SV wave, the relationship between the oblique input waves and the design ground motion was established in the free field. Further, the contributions to the two components of design ground motion of obliquely incident waves were discussed. The calculation model in time domain was achieved by the combination of the propagation characteristics of obliquely incident waves and the artificial boundary in the free field. The seismic response to the design ground motion was produced on the free surface. The verification of the 2D half-space model under oblique input waves indicated that the wave input method can accurately reflect the design ground motion on the free surface. Application of an earth-rock dam showed that oblique incidence of seismic waves results in significantly different dynamic response compared with the normal incidence. The proposed method can also be employed in the seismic analysis of large span structures with nonuniform ground motion input.
- Published
- 2018
- Full Text
- View/download PDF
3. Nano-scaled diffusional or dislocation creep analysis of single-crystal ZnO
- Author
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P. H. Lin, X. H. Du, Y. H. Chen, H. C. Chen, and J. C. Huang
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Physics ,QC1-999 - Abstract
The nanoindentation time-dependent creep experiments with different peak loads are conducted on c-plane (0001), a-plane (112¯0) and m-plane (101¯0) of single-crystal ZnO. Under nano-scaled indentation, the creep behavior is crystalline orientation-dependent. For the creep on (0001), the stress exponent at low loads is ∼1 and at high loads ∼4. The stress exponents under all loads are within 3∼7 for the creep on (112¯0) and (101¯0). This means that diffusion mechanism and dislocation mechanism is operative for different planes and loads. The relative difficulty of dislocations activation is an additional factor leading to the occurring of diffusion creep on the c-plane of single-crystal ZnO.
- Published
- 2016
- Full Text
- View/download PDF
4. Superior strength-ductility combination of a Co-rich CoCrNiAlTi high-entropy alloy at room and cryogenic temperatures
- Author
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X H Du, X F Huo, H T Chang, W P Li, G S Duan, J C Huang, B L Wu, N F Zou, and L Zhang
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high-entropy alloys ,multiple-phase microstructure ,mechanical properties ,strengthening and toughening mechanisms ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
In the present study, a Co-rich CoCrNi-AlTi high-entropy alloy was designed and fabricated by hot forging and 700 °C for 8 h annealing process. The microstructure of the resultant alloy was composed of three multicomponent-phases with the face-centered cubic (FCC) structure, hexagonal close-packed (HCP) structure and L1 _2 structure, respectively. The alloy exhibited a remarkable combination of tensile yield strength (gigapascal scale) and plasticity (uniform strain over 30%) at both room and cryogenic temperatures. The cooperative operation of multiple mechanisms consisting of refined-grain strengthening, second-phase strengthening, precipitation strengthening, stacking faults and phase-transformation toughening was suggested to be responsible for the excellent mechanical response.
- Published
- 2020
- Full Text
- View/download PDF
5. Conophylline Suppresses Angiotensin II-Induced Myocardial Fibrosis In Vitro via the BMP4/JNK Pathway
- Author
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X H Du, Y C Wang, Y N Bao, L Y Lv, and S Q Zhang
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medicine.medical_specialty ,Kinase ,General Medicine ,SMAD ,medicine.disease ,Angiotensin II ,General Biochemistry, Genetics and Molecular Biology ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Fibrosis ,Internal medicine ,Renin–angiotensin system ,medicine ,Myocardial fibrosis ,Anisomycin ,Transforming growth factor - Abstract
We studied the effects and mechanisms of action of conophylline in different concentrations in the original in vitro model of myocardial fibrosis (treatment of cardiac fibroblasts isolated form the hearts of newborn rats with angiotensin II). Viability, collagen content, and expression of related protein in cardiac fibroblasts were assessed using the MTT-test, Sircol assay, and Western blotting, respectively. Conophylline markedly protected the cultured cells against the development of angiotensin II-induced fibrosis, which was seen from reduced viability of fibroblasts, decreased collagen content, and down-regulation of the expression of α-smooth muscle actin (α-SMA). Conophylline did not affect the TGF-β pathway altered by angiotensin II, but markedly decreased the level of bone morphogenetic protein-4 (BMP4) enhanced by angiotensin II and BMP4 itself. Conophylline produced no effect on phosphorylation of α-SMA and Smad homologue-1/5/8, the classic BMP4 downstream pathway elements, but reduced the level of c-Jun N-terminal kinase (JNK) elevated by BMP4. Conophylline did not inhibit the development of myocardial fibrosis in the presence of JNK activator anisomycin. Thus, conophylline inhibited angiotensin II-provoked myocardial fibrosis via the BMP4/JNK pathway.
- Published
- 2021
6. Effective Model of Food Allergy in Mice Sensitized with Ovalbumin and Freud’s Adjuvant
- Author
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Y. Q. Zhang, Q. Q. Luo, G. Song, Y. Zhang, S. Y. Zhao, L. Z. Xu, X. H. Du, C. Wan, J. Y. Liu, J. W. Shao, and C. Y. Wang
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biology ,business.industry ,medicine.medical_treatment ,Ileum ,General Medicine ,Immunoglobulin E ,General Biochemistry, Genetics and Molecular Biology ,Jejunum ,Ovalbumin ,medicine.anatomical_structure ,Freund's adjuvant ,Immunology ,medicine ,biology.protein ,Sample collection ,business ,Adjuvant ,Sensitization - Abstract
To better explore the pathophysiology of FA and its therapy, we aimed to establish a simple and practicable FA model with Freund's adjuvant and introduce an easy and reliable laboratory evaluation method for assessment of inflammation in intestinal segments at different anatomical locations. BALB/c mice were sensitized with ovalbumin combined with Freund's adjuvant. Complete Freund's adjuvant was chosen for the first sensitization and two weeks later incomplete Freund's adjuvant was used for a second sensitization. Two weeks later, the sensitized mice were challenged with 50 mg ovalbumin every other day. After the 6 challenge, all mice were assessed for systemic anaphylaxis, and then sacrificed for sample collection. All sensitized mice showed anaphylactic symptoms and markedly increased levels of serum ovalbumin-specific IgE and IgG1. The activity of mast cell protease-1 (mMCPT-1) was significantly increased in the serum and interstitial fluid of the duodenum, jejunum, ileum, and colon. A successful FA model was established, of which inflammation occurred in the duodenum, jejunum, ileum, and colon. This model provides a reliable and simple tool for analysis of the mechanism of FA and methods of immunotherapy. Moreover, combined detection of ovalbumin-specific antibody and local mMCPT-1 levels could potentially be used as the major indicator for assessment of food allergy.
- Published
- 2021
7. [Role of CT and MRI image fusion and computer assisted simulation technique in guiding type Ⅲ and Ⅳ primary pelvic sarcoma surgeries]
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X H, Du, B M, Wang, B Y, Zhang, X, Liu, Z C, Tian, and W T, Yao
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Adult ,Male ,Osteosarcoma ,Adolescent ,Computers ,Margins of Excision ,Bone Neoplasms ,Sarcoma ,Middle Aged ,Magnetic Resonance Imaging ,Young Adult ,Treatment Outcome ,Humans ,Female ,Tomography, X-Ray Computed ,Aged ,Pelvic Neoplasms ,Retrospective Studies - Published
- 2022
8. Effective food allergy model in mice sensitized with ovalbumin and Freund’s adjuvant
- Author
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S. Y. Zhao, C. Wan, Y. Q. Zhang, L. Z. Xu, Y. Zhang, X. H. Du, C. Y. Wang, J. W. Shao, G. Song, Q. Q. Luo, and J. Y. Liu
- Subjects
Ovalbumin ,biology ,business.industry ,Food allergy ,Freund's adjuvant ,Immunology ,biology.protein ,Medicine ,business ,medicine.disease ,General Biochemistry, Genetics and Molecular Biology - Published
- 2021
9. Laboratory testing and numerical modeling of geomembrane electrical leak detection surveys
- Author
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W. J. Cen, H. N. He, J. Yan, Mohammad Shaifur Rahman, and X. H. Du
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Leak ,0211 other engineering and technologies ,Numerical modeling ,02 engineering and technology ,Geotechnical Engineering and Engineering Geology ,Laboratory testing ,Geomembrane ,021105 building & construction ,Environmental science ,Geotechnical engineering ,Leak detection ,Geosynthetics ,021101 geological & geomatics engineering ,Civil and Structural Engineering - Abstract
Laboratory tests were conducted to evaluate the influence of the positions of positive and negative electrodes on the electrical response of a leak in the geomembrane. A numerical evaluation was performed to model the laboratory conditions and to investigate the effect of dipole spacing, excitation voltage, and impoundment resistivity on the leak detection sensitivity. The results of laboratory tests show that leaks cannot be identified when the positive electrode is very close to the leak and the electrical response of a leak in the geomembrane is independent of the position of the negative electrode. The results from the 3D finite element model indicate that leak detection sensitivity improves nonlinearly as the dipole spacing increases, and it tends to be stable after the dipole spacing exceeds 5% of the length of the survey line. The results also indicate that there is an almost linear increase in the leak detection sensitivity with increasing excitation voltage. Substantial improvement was obtained in the leak detection sensitivity for a greater impoundment resistivity. The numerical results indicate that 90% of leaks in a geomembrane liner can be effectively detected and accurately located for the 3D finite element model of a geomembrane lined earth-rock dam.
- Published
- 2020
10. miR-455 подавляет пролиферацию и способствует апоптозу клеток HepG2, направленно воздействуя на экспрессию RhoC
- Author
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X. H. Du, M. Wang, S. L. Xie, Z. W. Zhao, and Guoyue Lv
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Tumor suppressor gene ,biology ,Apoptosis ,microRNA ,Cancer research ,biology.protein ,RhoC ,PTEN ,Luciferase ,Caspase 3 ,General Medicine ,Transfection - Abstract
Hepatocellular carcinoma (HCC) is a common malignancy worldwide with poor prognosis and high mortality. The aberrant expression or alteration of microRNAs (miRNAs) contributes to the development and progression of cancer. Studies have shown that miR-455 plays a regulatory role in the development of HCC. Therefore, in the present study, the role of miR-455 was analyzed in HepG2 cells proliferation and apoptosis using MTT and flow cytometry methods. Binding sites were predicted by bioinformatics and luciferase assay was used to verify the target relationship between miR-455 and RhoC-encoding gene RHOC. After that, the effects of miR-455 on RHOC and its product RhoC, were explored by qPCR and Western blotting. As PTEN is a key tumor suppressor gene in HCC, and Bcl-2 and Caspase 3 are important indication of apoptosis, expression levels of PTEN, Bcl2 and Caspase 3 proteins were determined in cells overexpressing RhoC. We show that miR-455 promotes HepG2 cells apoptosis and inhibits proliferation. Bioinformatics analysis and luciferase assay indicate that specific recognition sites for miR-455 are within the RhoC 3'-UTR. Luciferase activity was significantly lower in the cells co-transfected with miR-455 mimics and RhoC-WT (p < 0.01) as compared to that in control cells, pointing that RHOC gene is, indeed, targeted by miR-455. RHOC mRNA was significantly reduced after miR-455 transfection in HepG2 cells. In addition, we show that RhoC could activate the HCC cells proliferation ability and inhibit apoptosis rate (p < 0.01), and decrease expression of PTEN and Caspase 3 (p < 0.01), while upregulating levels of Bcl2. In conclusion, our study indicates that miR-455 plays a suppressive role in HCC development by targeting RhoC-encoding mRNA.
- Published
- 2020
11. miR-455 Inhibits HepG2 Cell Proliferation and Promotes Apoptosis by Targeting RhoC
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S. L. Xie, M. Wang, X. H. Du, Z. W. Zhao, and G. Y. Lv
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Structural Biology ,Biophysics - Published
- 2020
12. Impact of Underliner on the Local Deformation of HDPE Geomembranes
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Mohammad Shaifur Rahman, J. Yan, H. Wang, X. H. Du, and W. J. Cen
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021110 strategic, defence & security studies ,Materials science ,0211 other engineering and technologies ,02 engineering and technology ,Deformation (meteorology) ,Polyethylene ,Puncture tests ,Geotechnical Engineering and Engineering Geology ,chemistry.chemical_compound ,chemistry ,Geomembrane ,Geotechnical engineering ,High-density polyethylene ,Geosynthetics ,021101 geological & geomatics engineering ,General Environmental Science - Abstract
A series of short-term puncture tests is conducted to investigate the deformation behavior of a 0.5-mm-thick high-density polyethylene (HDPE) geomembrane on particulate underliners subjecte...
- Published
- 2021
13. Therapeutic efficacy of dexmedetomidine on chronic obstructive pulmonary disease via downregulating lncRNA PACER
- Author
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X-H, Du, S-S, Li, G-S, Xiong, G-M, Yang, W, Shen, S-B, Sun, X-L, Ye, L, Li, and Z-Y, Weng
- Subjects
Rats, Sprague-Dawley ,Pulmonary Disease, Chronic Obstructive ,Cell Movement ,Animals ,Down-Regulation ,Humans ,Epithelial Cells ,RNA, Long Noncoding ,Dexmedetomidine ,Cell Proliferation ,Rats - Abstract
The aim of the study was to clarify the therapeutic mechanism of Dexmedetomidine (DEX) on the chronic obstructive pulmonary disease (COPD) and its regulatory effect on long non-coding RNA (lncRNA) PACER.Serum level of PACER in COPD patients was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The diagnostic potential of PACER in COPD was assessed by plotting ROC curves. The in vivo COPD model was generated in rats by cigarette smoking exposure. Primary rat alveolar epithelial cells were isolated, purified and cultured. After overexpression of PACER in primary rat alveolar epithelial cells, proliferative and migratory abilities were assessed by cell counting kit-8 (CCK-8) and transwell assay, respectively. Subsequently, we detected changes in PACER expression, viability and migratory potentials in primary rat alveolar epithelial cells harvested from control rats, and those harvested from COPD rats and induced with either DEX or not. Rescue experiments were conducted to uncover the involvement of PP2A in PACER-regulated cell phenotypes.PACER was upregulated in serum of COPD patients, which was a potential biomarker for diagnosing COPD. Overexpression of PACER in primary rat alveolar epithelial cells enhanced proliferative and migratory abilities. Compared with primary rat alveolar epithelial cells harvested from control rats, proliferative and migratory abilities were stronger in those harvested from COPD rats and induced with either DEX or not. Notably, DEX induction decreased PACER expression, and proliferative and migratory abilities in primary rat alveolar epithelial cells harvested from COPD rats. Overexpression of PP2A could partially abolish the promotive effects of PACER on proliferative and migratory abilities in DEX-induced primary rat alveolar epithelial cells harvested from COPD rats.PACER drives the proliferative and migratory abilities of alveolar epithelial cells through activating PP2A. Dexmedetomidine is conducive to COPD treatment by downregulating PACER.
- Published
- 2020
14. Conophylline Suppresses Angiotensin II-Induced Myocardial Fibrosis In Vitro via the BMP4/JNK Pathway
- Author
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S Q, Zhang, Y N, Bao, L Y, Lv, X H, Du, and Y C, Wang
- Subjects
Smad5 Protein ,MAP Kinase Kinase 4 ,Angiotensin II ,Myocardium ,Primary Cell Culture ,Bone Morphogenetic Protein 4 ,Fibroblasts ,Endomyocardial Fibrosis ,Models, Biological ,p38 Mitogen-Activated Protein Kinases ,Rats ,Smad1 Protein ,Transforming Growth Factor beta1 ,Animals, Newborn ,Gene Expression Regulation ,Smad8 Protein ,Animals ,Collagen ,Antifibrotic Agents ,Phosphorylation ,Rats, Wistar ,Vinca Alkaloids ,Signal Transduction - Abstract
We studied the effects and mechanisms of action of conophylline in different concentrations in the original in vitro model of myocardial fibrosis (treatment of cardiac fibroblasts isolated form the hearts of newborn rats with angiotensin II). Viability, collagen content, and expression of related protein in cardiac fibroblasts were assessed using the MTT-test, Sircol assay, and Western blotting, respectively. Conophylline markedly protected the cultured cells against the development of angiotensin II-induced fibrosis, which was seen from reduced viability of fibroblasts, decreased collagen content, and down-regulation of the expression of α-smooth muscle actin (α-SMA). Conophylline did not affect the TGF-β pathway altered by angiotensin II, but markedly decreased the level of bone morphogenetic protein-4 (BMP4) enhanced by angiotensin II and BMP4 itself. Conophylline produced no effect on phosphorylation of α-SMA and Smad homologue-1/5/8, the classic BMP4 downstream pathway elements, but reduced the level of c-Jun N-terminal kinase (JNK) elevated by BMP4. Conophylline did not inhibit the development of myocardial fibrosis in the presence of JNK activator anisomycin. Thus, conophylline inhibited angiotensin II-provoked myocardial fibrosis via the BMP4/JNK pathway.
- Published
- 2020
15. [A multicenter randomized prospective study of concurrent chemoradiation with 60 Gy versus 50 Gy for inoperable esophageal squamous cell carcinoma]
- Author
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Y J, Xu, W G, Zhu, Z X, Liao, Y, Kong, W W, Wang, J C, Li, R, Huang, H, He, X M, Yang, L P, Liu, Z W, Sun, H J, He, Y, Bao, M, Zeng, J, Pu, W Y, Hu, J, Ma, H, Jiang, Z G, Liu, T T, Zhuang, B X, Tan, X H, Du, G Q, Qiu, X, Zhou, Y L, Ji, X, Hu, J, Wang, H L, Ma, X, Zheng, J, Huang, A W, Liu, X D, Liang, H, Tao, J Y, Zhou, Y, Liu, and M, Chen
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Male ,Esophageal Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Female ,Chemoradiotherapy ,Esophageal Squamous Cell Carcinoma ,Fluorouracil ,Prospective Studies ,Cisplatin ,Middle Aged ,Combined Modality Therapy - Published
- 2020
16. [Take the rational view on the application of robotic surgery in gastrointestinal field in China]
- Author
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X H, Du and Y, Yan
- Subjects
China ,Robotic Surgical Procedures ,Gastrointestinal Diseases ,Humans ,Laparoscopy ,Digestive System Surgical Procedures - Abstract
Since its introduction in China, the rapid development of robotic surgical system has brought a new trend in gastrointestinal surgery. Although clinical trials have proven its safety and effectiveness compared with traditional laparoscopic surgery, robotic gastrointestinal surgery has no obvious advantages in either short-term efficacy or long-term survival after surgery. Significantly increased costs have not brought corresponding clinical benefits, and that has limited robotic surgery to become the mainstream option for gastrointestinal surgery. In this paper, the clinical findings of robotic gastrointestinal surgery were reviewed, and the application of robotic surgical system in gastrointestinal surgery should be viewed rationally. The majority of gastrointestinal surgeons should not take the so-called "advanced equipment" as a monopolized asset, but choose surgery methods that the patients can benefit from, doctors are satisfied with, and can reflect the best socioeconomic benefits for the patients. With the development of a new generation of robotic surgical system and the support of more high-quality evidence-based medicine, it is believed that robotic gastrointestinal surgery will go towards a better future along a rational and objective track.机器人手术系统自引入国内以来发展迅速,带来了胃肠外科的新潮流。尽管临床试验已证明其安全有效,但与传统腹腔镜手术相比,机器人胃肠手术在术后短期效果和长期生存方面优势并不明显。加上显著增加的手术费用未获得相应的临床获益,限制了机器人手术成为胃肠外科的主流选择。本文回顾机器人胃肠手术临床研究结果,呼吁当下应理性看待机器人手术系统在胃肠外科的应用。广大胃肠外科医生不应以所谓的"先进设备"为垄断资本,而应选择患者受益、医生满意、更能体现最佳社会效益和经济效益的手术方式为广大病患服务。随着新一代机器人手术系统的研发和更多的高质量循证医学证据支撑,相信机器人胃肠外科将循着理性客观的轨迹走向美好的未来。.
- Published
- 2020
17. [Breakthrough of invasive fungal disease with posaconazole as primary prophylaxis after induction chemotherapy for acute myeloid leukemia]
- Author
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R Z, Pei, Y, Lu, P S, Zhang, X H, Liu, D, Chen, X H, Du, K Y, Sha, S Y, Li, J J, Cao, L G, Chen, X X, Zhuang, and S H, Tang
- Subjects
Leukemia, Myeloid, Acute ,Antifungal Agents ,Humans ,Induction Chemotherapy ,Voriconazole ,Antibiotic Prophylaxis ,Opportunistic Infections ,Triazoles ,Invasive Fungal Infections ,Retrospective Studies - Published
- 2020
18. Oblique Incidence of Seismic Wave Reflecting Two Components of Design Ground Motion
- Author
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L. N. Yuan, X. H. Du, D. J. Li, and W. J. Cen
- Subjects
Article Subject ,Field (physics) ,Scattering ,Mechanical Engineering ,Acoustics ,Oblique case ,02 engineering and technology ,010502 geochemistry & geophysics ,Geotechnical Engineering and Engineering Geology ,Condensed Matter Physics ,Free field ,01 natural sciences ,lcsh:QC1-999 ,Seismic wave ,Seismic analysis ,020401 chemical engineering ,Mechanics of Materials ,Free surface ,P-wave ,0204 chemical engineering ,lcsh:Physics ,Geology ,0105 earth and related environmental sciences ,Civil and Structural Engineering - Abstract
The wave field on the artificial boundary was separated into the free field without local topography effect and scattering field induced by local topography effect. The simulation of the free field under obliquely incident waves was conducted. Based on the assumption that the components of design ground motion were treated as the coincidence of oblique P wave and oblique SV wave, the relationship between the oblique input waves and the design ground motion was established in the free field. Further, the contributions to the two components of design ground motion of obliquely incident waves were discussed. The calculation model in time domain was achieved by the combination of the propagation characteristics of obliquely incident waves and the artificial boundary in the free field. The seismic response to the design ground motion was produced on the free surface. The verification of the 2D half-space model under oblique input waves indicated that the wave input method can accurately reflect the design ground motion on the free surface. Application of an earth-rock dam showed that oblique incidence of seismic waves results in significantly different dynamic response compared with the normal incidence. The proposed method can also be employed in the seismic analysis of large span structures with nonuniform ground motion input.
- Published
- 2018
19. FLT3 and FLT3-ITD gene mutations and prognosis in patients with acute myeloid leukemia
- Author
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L G, Chen, R Z, Pei, Y, Lu, P S, Zhang, X H, Liu, X H, Du, D, Chen, J J, Cao, and S Y, Li
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Leukemia, Myeloid, Acute ,fms-Like Tyrosine Kinase 3 ,Mutation ,Humans ,Prognosis - Published
- 2019
20. [Ikaros family zinc finger 1 mutation is a poor prognostic factor for adult Philadelphia chromosome positive acute lymphoblastic leukemia]
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S H, Tang, Y, Lu, P S, Zhang, X H, Liu, X H, Du, D, Chen, S Y, Li, J J, Cao, L G, Chen, J, Le, S Y, Qian, Y W, Hong, and R Z, Pei
- Subjects
Adult ,Ikaros Transcription Factor ,Humans ,Philadelphia Chromosome ,Zinc Fingers ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,Prognosis ,Retrospective Studies - Published
- 2019
21. Ultra-high strength Mg-9Gd-4Y-0.5Zr alloy with bi-modal structure processed by traditional extrusion
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D. Wu, N. T. Hu, X. H. Du, Rongshi Chen, Y. F. Zhang, M. Hong, and S. S. A. Shah
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010302 applied physics ,Materials science ,Magnesium ,Alloy ,Metallurgy ,Metals and Alloys ,chemistry.chemical_element ,Recrystallization (metallurgy) ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Microstructure ,01 natural sciences ,chemistry ,Mechanics of Materials ,Aluminium ,0103 physical sciences ,Ultimate tensile strength ,Materials Chemistry ,engineering ,Extrusion ,0210 nano-technology ,Tensile testing - Abstract
It is usual to observe that multi-scale structures can lead to combined strength and ductility both in aluminum alloys and steels, but related research has been seldom reported yet in magnesium alloys. In this study, applying traditional one step extrusion, we have successfully obtained a bimodal (Mg-9Gd-4Y-0.5Zr) alloy capable of ultra-high strength. The characterized sample reveal a bi-modal microstructure with two constitutions, i.e. stretched coarse-grain region with strong basal fiber texture and recrystallization fine-grain region. The bi-modal structured sample exhibit excellent mechanical properties with an ultimate strength 508 MPa and elongation 8% via 400 °C extrusion and subsequently 200 °C-60 h peak aging process. Ultra-high strength can be attributed to its strong extrusion texture in stretched coarse grains and dispersed nano-scale precipitates. This unique bimodal structure could be produced easily by one step extrusion, which is quite reliable and low costs in industrial applications of magnesium alloys with ultra-high strength as well as ideal ductility.
- Published
- 2016
22. Long-term Stability Enabling Technology of Silicon-Based Piezoresistive MEMS Pressure Sensor
- Author
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M J Zhu, S Liu, X H Du, and D Liu
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Microelectromechanical systems ,History ,Silicon ,business.industry ,Computer science ,Factory method pattern ,chemistry.chemical_element ,Piezoresistive effect ,Pressure sensor ,Automotive engineering ,Bottleneck ,Computer Science Applications ,Education ,Vibration ,chemistry ,Aerospace ,business - Abstract
Silicon-based piezoresistive microelectromechanical systems (MEMS) pressure sensor is one of the best studied and commercialized devices among all MEMS devices due to simple structure, easy reading circuit, strong batch fabrication capability and low price. The biggest technical bottleneck of this sensor for high-end applications such as aerospace is long-term stability after packaging. Therefore, long-term stability improvement technologies, as the common key technologies, have been widely concerned by academia and industry. In this paper, three common enabling technologies including pulsating fatigue, thermal-cold cycling and vibration aging are adopted to evaluate the effect of long-term stability of silicon-based piezoresistive MEMS pressure sensors by using control variable method and orthogonal test (OT) method. The comparative test results indicate that all these three technologies can improve the long-term stability of the pressure sensor. In addition, an optimized combination of environmental stress parameters is found to improve the stability more than 90% higher than before the test. The long-term stability of the sensors through the optimal parameter combination aging method is better than the original factory method. The research results can be used for reference to improve the long-term stability of various silicon-based pressure sensors.
- Published
- 2020
23. First Report of Chlorosis and Root Rot Caused by Pythium ultimum in Garden Pansy in China
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S. L. He, J. Y. Mu, W. Q. Jia, X. P. Zhu, X. H. Du, H. C. Liu, S. P. Wang, and Y. L. Wang
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Horticulture ,Intergenic region ,Chlorosis ,Pathogen detection ,Ornamental plant ,Root rot ,Plant Science ,Fungal morphology ,Biology ,biology.organism_classification ,Pathogenicity ,Agronomy and Crop Science ,Pythium ultimum - Published
- 2020
24. [Genetic typing and susceptibility testing of strains from
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Q F, Liang, X H, Du, G Y, Su, Y, Zhang, Z Q, Wang, and K, Cao
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Keratitis ,Methicillin-Resistant Staphylococcus aureus ,Genotype ,Humans ,Microbial Sensitivity Tests ,Conjunctivitis ,Anti-Bacterial Agents ,Multilocus Sequence Typing - Published
- 2018
25. [Effect of FLT3-ITD with DNMT3A R882 double-mutation on the prognosis of acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation]
- Author
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S H, Tang, Y, Lu, P S, Zhang, X H, Liu, X H, Du, D, Chen, K Y, Sha, S Y, Li, J J, Cao, L G, Chen, X X, Zhuang, R Z, Pei, and X W, Tang
- Subjects
Adult ,Male ,白血病,髓样,急性 ,Adolescent ,造血干细胞移植 ,Hematopoietic stem cell transplantation ,DNMT3A R882 mutation ,Middle Aged ,Prognosis ,FLT3-ITD mutation ,DNA Methyltransferase 3A ,论著 ,Leukemia, Myeloid, Acute ,Young Adult ,fms-Like Tyrosine Kinase 3 ,Child, Preschool ,Mutation ,FLT3-ITD突变 ,Humans ,Female ,DNA (Cytosine-5-)-Methyltransferases ,Child ,Nucleophosmin ,DNMT3A R882突变 ,Retrospective Studies - Abstract
目的 探讨FLT3-ITD和DNMT3A R882双突变对急性髓系白血病(AML)患者allo-HSCT预后的影响。 方法 使用直接测序法检测206例接受allo-HSCT的AML患者(M3和使用分子靶向药物索拉菲尼的病例除外)初诊时骨髓中常见的基因突变组套(包括FLT3-ITD、DNMT3A、c-kit、CEBPA、FLT3-TKD、NPM1),回顾性分析患者的临床资料,比较各基因突变组的移植预后。 结果 ①206例AML患者中男104例,女102例,中位年龄38(3~63)岁。FAB分型:M0 6例,M1 24例,M2 56例,M4 39例,M5 63例,M6 6例,不能分类12例。②全部206例患者根据初诊时的突变基因情况分为4组:FLT3-ITD+ DNMT3A R882+组(A组)19例,FLT3-ITD+ DNMT3A R882−组(B组)38例,FLT3-ITD−DNMT3A R882+组(C组)21例,FLT3-ITD−DNMT3A R882−组(D组)128例。四组间性别、年龄、初诊时白细胞计数、FAB分型、移植前疾病状态、染色体核型、供者类型、预处理方案及GVHD发生率比较,差异无统计学意义(P>0.05)。③A组和B、C、D组比较,2年累积复发率较高[分别为(72.2±2.6)%、(38.6±0.6)%、(36.8±1.6)%、(27.8±0.1)%,P值均
- Published
- 2018
26. [miR-455 Inhibits HepG2 Cell Proliferation and Promotes Apoptosis by Targeting RhoC]
- Author
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S L, Xie, M, Wang, X H, Du, Z W, Zhao, and G Y, Lv
- Subjects
Gene Expression Regulation, Neoplastic ,MicroRNAs ,Carcinoma, Hepatocellular ,rhoC GTP-Binding Protein ,Liver Neoplasms ,Humans ,Apoptosis ,Hep G2 Cells ,Cell Proliferation - Abstract
Hepatocellular carcinoma (HCC) is a common malignancy worldwide with poor prognosis and high mortality. The aberrant expression or alteration of microRNAs (miRNAs) contributes to the development and progression of cancer. Studies have shown that miR-455 plays a regulatory role in the development of HCC. Therefore, in the present study, the role of miR-455 was analyzed in HepG2 cells proliferation and apoptosis using MTT and flow cytometry methods. Binding sites were predicted by bioinformatics and luciferase assay was used to verify the target relationship between miR-455 and RhoC-encoding gene RHOC. After that, the effects of miR-455 on RHOC and its product RhoC, were explored by qPCR and Western blotting. As PTEN is a key tumor suppressor gene in HCC, and Bcl-2 and Caspase 3 are important indication of apoptosis, expression levels of PTEN, Bcl2 and Caspase 3 proteins were determined in cells overexpressing RhoC. We show that miR-455 promotes HepG2 cells apoptosis and inhibits proliferation. Bioinformatics analysis and luciferase assay indicate that specific recognition sites for miR-455 are within the RhoC 3'-UTR. Luciferase activity was significantly lower in the cells co-transfected with miR-455 mimics and RhoC-WT (p0.01) as compared to that in control cells, pointing that RHOC gene is, indeed, targeted by miR-455. RHOC mRNA was significantly reduced after miR-455 transfection in HepG2 cells. In addition, we show that RhoC could activate the HCC cells proliferation ability and inhibit apoptosis rate (p0.01), and decrease expression of PTEN and Caspase 3 (p0.01), while upregulating levels of Bcl2. In conclusion, our study indicates that miR-455 plays a suppressive role in HCC development by targeting RhoC-encoding mRNA.
- Published
- 2018
27. Characterization and Functional Applications of Nanoporous Ag Foams Prepared by Chemical Dealloying
- Author
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X. Wang, J.C. Huang, T. Y. Wu, X. H. Du, Y. Y. Chu, W. Y. Tsai, and S.Y. Chen
- Subjects
chemistry.chemical_classification ,Structural material ,Materials science ,Nanoporous ,Metals and Alloys ,Modulus ,Polymer ,Condensed Matter Physics ,Characterization (materials science) ,Catalysis ,chemistry ,Mechanics of Materials ,visual_art ,Electrode ,Materials Chemistry ,visual_art.visual_art_medium ,Ceramic ,Composite material - Abstract
In this study, the pure Ag nanoporous foams, with open cell pore volume fractions 55 to 70 pct and pore sizes 100 to 400 nm, have been prepared by chemical dealloying. The Ag nanoporous foams possess favorable modulus (~0.7 GPa) and strength (~14 MPa), much higher than most of the polymers or ceramic foams. It is found that the Ag nanoporous foams are appropriate candidates for the catalytic and electrode applications. However, they do not exhibit efficient anti-bacterial effect, unless much smaller bacteria with cell sizes of 100 nm or less in the neighborhood are encountered.
- Published
- 2015
28. Molecular cloning and expression analysis of jasmonic acid dependent but salicylic acid independent LeWRKY1
- Author
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Q Z Zhang, X H Du, Qingpeng Sun, M Lu, Jinbao Pan, Nan Zhangjie, Y K Yu, W X Wang, Jun Han, and L F Wang
- Subjects
DNA, Complementary ,Cyclopentanes ,Biology ,Genes, Plant ,Lycopersicon ,chemistry.chemical_compound ,Solanum lycopersicum ,Plant Growth Regulators ,Rapid amplification of cDNA ends ,Gene Expression Regulation, Plant ,Complementary DNA ,Genetics ,Oxylipins ,RNA, Messenger ,Cloning, Molecular ,Molecular Biology ,Plant Proteins ,Botrytis cinerea ,Regulation of gene expression ,Plant Stems ,Abiotic stress ,Jasmonic acid ,food and beverages ,General Medicine ,biology.organism_classification ,Plant Leaves ,chemistry ,Biochemistry ,Botrytis ,Salicylic Acid ,Salicylic acid ,Transcription Factors - Abstract
Various plant genes can be activated or inhibited by phytohormones under conditions of biotic and abiotic stress, especially in response to jasmonic acid (JA) and salicylic acid (SA). Interactions between JA and SA may be synergistic or antagonistic, depending on the stress condition. In this study, we cloned a full-length cDNA (LeWRKY1, GenBank accession No. FJ654265) from Lycopersicon esculentum by rapid amplification of cDNA ends. Sequence analysis showed that this gene is a group II WRKY transcription factor. Analysis of LeWRKY1 mRNA expression in various tissues by qRT-PCR showed that the highest and lowest expression occurred in the leaves and stems, respectively. In addition, LeWRKY1 expression was induced by JA and Botrytis cinerea Pers., but not by SA.
- Published
- 2015
29. [Epidemiologic study of tear film lipid layer thickness measurement in the population of Taishitun Community in Beijing]
- Author
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Q F, Liang, X H, Du, Y D, Su, N L, Wang, Z J, Wei, and Antoine, Labbé
- Subjects
Adult ,Male ,Adolescent ,Meibomian Glands ,Middle Aged ,Lipids ,Epidemiologic Studies ,Young Adult ,Cross-Sectional Studies ,Beijing ,Tears ,Humans ,Dry Eye Syndromes ,Female ,Aged - Published
- 2017
30. [Effect of two different acellular lung matrices on α-SMA expression in A549 cells]
- Author
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C, Chen, Z Y, Wang, J, Weng, Z B, Wang, J, Mei, X H, Du, and L, Wang
- Subjects
Lung Neoplasms ,Down-Regulation ,Adenocarcinoma of Lung ,Adenocarcinoma ,Fibroblasts ,Fibrosis ,Actins ,Idiopathic Pulmonary Fibrosis ,Rats ,Rats, Sprague-Dawley ,Bleomycin ,A549 Cells ,Animals ,Humans ,RNA, Messenger ,Lung ,Cells, Cultured - Published
- 2017
31. [Study on the evaluation of pterygium activity with
- Author
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Q F, Liang, C, Gao, H, Liang, B, Li, X H, Du, and Antoine, Labbe
- Subjects
Adult ,Cornea ,Keratitis ,Male ,Microscopy, Confocal ,Neovascularization, Pathologic ,Case-Control Studies ,Epithelium, Corneal ,Humans ,Cell Count ,Female ,Prospective Studies ,Pterygium - Published
- 2016
32. [In vivo confocal microscopy evaluation of meibomian glands in meibomian gland dysfunction patients]
- Author
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Q F, Liang, C, Gao, H, Liang, X H, Du, N L, Wang, and Antoine, Labbe
- Subjects
Cornea ,Microscopy, Confocal ,Case-Control Studies ,Surveys and Questionnaires ,Tears ,Eyelid Diseases ,Humans ,Meibomian Glands ,Cell Count ,Prospective Studies ,Conjunctiva ,Fibrosis - Abstract
To observe the morphology, fibrosis grade and inflammatory infiltration of meibomian glands using in vivo confocal microscopy(IVCM)in meibomian gland dysfunction(MGD)patients.A prospective case-controlled study. According to the diagnostic criteria of MGD, 20 MGD patients(20 eyes)were included in our study from August to October 2015. Fifteen normal subjects(15 eyes)were also studied. METHODS All subjects completed the questionnaire of the Ocular Surface Disease Index(OSDI), lid margin and ocular surface examination by slit lamp microscropy, tear film break-up time(TBUT)test, corneal and conjunctival staining(Oxford scale), Schirmer I test, infrared meibomian photography and IVCM. Main outcomes in IVCM included meibomian gland acinar longest diameter(MGALD), meibomian gland acinar shortest diameter(MGASD), meibomian gland acinar unit density(MGAUD), meibomian gland acinar unit area(MGAUA), meibomian gland inflammatory cell density and fibrosis degree. The parameters between the MGD group and the control group were compared using the independent samples t test.The OSDI score[(31.80±22.97)points], 1id margin abnormality score[(3.10±0.31)points], loss rate of meibomian glands(38.31%±19.94%)and corneal and conjunctival staining score[1.00(2.75)points]in the MGD group were obviously higher than those in the control group[(7.93±6.51)points,(0.33±0.31)points, 21.31% ± 7.70%, and 0.00(1.00)points, P=0.001, P0.001, P=0.004, and P=0.037, respectively]. The TBUT was significantly lower in the MGD group[(3.35±2.28)s]than in the control group[(6.67±2.51)s, P0.001]. According to Schirmer I test, there was no significant difference in the two groups(P=0.139). The mean values of MGALD[(156.80 ± 46.10)μm], MGASD[(38.75 ± 11 .72)μm], MGAUA[(10 113.84 ± 5 531.21)μm(2)], meibomian gland inflammatory cell density[(621.90 ± 405.63)cells/mm(2)]and fibrosis degree 1.50(1.00)in the MGD patients were larger than those in the control group[(67.47 ± 9.117)μm,(22.00 ± 2.95)μm,(3 102.13 ± 1111.97)μm(2),(188.80 ± 72.25)cells/mm(2), and 0.00(0.00), all P0.001, respectively]. The mean MGAUD was lower in the MGD patients[(61.10 ± 34.97)glands/mm(2)]than in the control group[(105.07±18.58)glands/mm(2), P0.001].IVCM was pertinent to investigate the meibomian glands by detecting the irregularity of meibomian orifices, the diameter and area, and the inflammation and fibrosis levels in MGD patients. It may have a potential clinical value for the diagnosis of MGD. (Chin J Ophthalmol, 2016, 52: 649-656).
- Published
- 2016
33. [Clinical features and prognostic analysis of high-risk acute promyelocytic leukemia patients]
- Author
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R Z, Pei, T, Si, Y, Lu, P S, Zhang, X H, Liu, P P, Ye, D, Chen, X H, Du, J X, Ma, and J, Jin
- Subjects
Oncogene Proteins, Fusion ,Platelet Count ,Remission Induction ,Cytarabine ,临床特征 ,Clinical features ,预后 ,Prognosis ,Leukemia, promyelocytic, acute ,Survival Rate ,论著 ,Leukocyte Count ,Recurrence ,白血病,早幼粒细胞,急性 ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Protein Isoforms ,Retrospective Studies - Abstract
To investigate the clinical features and outcomes of high-risk acute promyelocytic leukemia (APL) patients.A retrospective analysis was conducted to compare the clinical characteristics and prognosis of 118 high-risk APL patients (WBC≥10 × 10(9)/L) and 234 low and intermedia-risk patients (WBC10×10(9)/L) from January 2003 to April 2015, who were treated in the First Affiliated Hospital of Zhejiang University and Yinzhou People's Hospital affiliated to Medical College of Ningbo University.The initial platelet counts of high-risk APL were significantly lower than that of low and intermediate-risk groups (P=0.003); the major type of PML-RARα isoforms in high-risk patients was short-form (51.8% vs 28.2%, P0.001); the early death (ED) rate of high-risk patients was higher than low and intermedia-risk patients (20.3% vs 2.6%, P0.001); in contrast, the complete remission (CR) rate and 5 years estimated overall survival (OS) rate of the former were lower than the latter (76.3% vs 94.9%, P0.001; 74.2% vs 93.7%, P0.001). However, the CR rate (P=0.682) and 5 years estimated OS rate (P=0.481) did not have difference when the ED patients were excluded. The 5 years estimated relapse-free survival (RFS) and central nervous system (CNS) relapse were 82.7%, 9.4%, respectively, which were lower than low and intermediate-risk groups (87.8%, 1.4% ) with statistic difference (P=0.048, 0.002). High-dose cytarabine and intrathecal chemotherapy may reduce the risk of CNS relapse.The outcomes of high-risk APL patients were worse than low and intermediate-risk group owing to the high ED rate and CNS relapse, it was important to decrease the ED rate and emphasis the CNS prophylaxis for high-risk APL patients.
- Published
- 2016
34. [The research advances of psychological disorder in patients with dry eye]
- Author
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X H, Du and Q F, Liang
- Subjects
Biomedical Research ,Mental Disorders ,Quality of Life ,Humans ,Dry Eye Syndromes ,Vision, Ocular - Abstract
In clinical practice, dry eye disease (DED) is recognized as one of the most frequent reasons for chronic ocular surface disorder, which can cause the damage to the ocular surface and some symptoms associated with ocular discomfort and impaired visual quality. This common ocular problem is characterized by high incidence and difficulty in treatment. DED can make the visual disturbance and degrade the quality of everyday life and social activities in different levels. Some patients with DED often report psychological changes because of the symptoms of ocular discomfort. This article mainly summarizes the characteristics and mechanism of psychological disorder in patients with DED.
- Published
- 2016
35. MICROPROPAGATION OF TREE PEONY FROM LATERAL BUDS
- Author
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W.-Q. Jia, Y.-P. Zhao, H.-C. Liu, and X.-H. Du
- Subjects
Tree (data structure) ,Horticulture ,Micropropagation ,Biology - Published
- 2012
36. Experimental Evaluation on Cyclic Shear Behavior of Geomembrane–Concrete Interfaces
- Author
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Y. J. Sun, X. H. Du, W. J. Cen, and H. Wang
- Subjects
Shear rate ,Damping ratio ,Materials science ,Shear stiffness ,Shear (geology) ,Geomembrane ,Mechanics of Materials ,Mechanical Engineering ,Composite number ,General Materials Science ,Cyclic shear ,Composite material ,Geosynthetics - Abstract
A series of cyclic shear tests was conducted to reveal the cyclic shear behavior of the interfaces between three types of geomembranes (smooth geomembranes, textured geomembranes, and composite geomembranes) and no-fines concrete. Hysteresis loops and backbone curves were obtained under different vertical pressures and shear-displacement amplitudes. The test results indicate that the textured geomembrane–concrete interface presents higher cyclic friction angles than the other two interfaces. The vertical pressure-dependent shear stiffness and damping ratio were used to evaluate the cyclic shear strength and damping behavior of the different geomembrane–concrete interfaces. In addition, the influence of shear rate and cycle number on the cyclic shear behavior of the geomembrane–concrete interfaces was considered, but there is little difference among experimental data for a specific interface. By analyzing the damage observed for the different geomembranes in the test, the shear behavior of these three interfaces between geomembranes and no-fines concrete was further evaluated. Finally, a reasonable choice of geomembrane is suggested for the stability and integrity of geomembranes in practical geomembrane engineering.
- Published
- 2018
37. Over-expression of a Populus peroxisomal ascorbate peroxidase (PpAPX) gene in tobacco plants enhances stress tolerance
- Author
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X. H. Du, R. L. Hai, X. N. Jiang, H. Lu, and Y. J. Li
- Subjects
biology ,Abiotic stress ,Transgene ,fungi ,food and beverages ,Plant Science ,Genetically modified crops ,Peroxisome ,biology.organism_classification ,APX ,Molecular biology ,Gene expression ,Botany ,Genetics ,biology.protein ,Cauliflower mosaic virus ,Agronomy and Crop Science ,Peroxidase - Abstract
Ascorbate peroxidase (APX) plays an important role in the metabolism of hydrogen peroxide in higher plants. We studied the effect of over-expressing a Populus peroxisomal ascorbate peroxidase (PpAPX) gene under the control of the cauliflower mosaic virus 35S promoter or the rd29 promoter in transgenic tobacco. High levels of PpAPX gene expression were observed in 35S-PpAPX transgenic plants, with a 50% increase in APX activity. The constitutive expression of PpAPX in the tobacco exhibited no morphological abnormalities, while significantly increased root growth was observed in transgenic plants, when compared to control plants. Several independently transformed lines were propagated and evaluated for resistance to methyl viologen (MV), drought and salt stress. Visual assessment of transgenic and control lines exposed to MV (50 or 100 μmol) confirmed that over-expression of APX minimized leaf damage. APX activity was nearly 80% higher in the leaves of transgenic plants in response to drought or salt stresses. Moreover, the transgenic tobacco also showed significantly improved drought resistance and salt tolerance at the vegetative stage. RNA blot analysis indicated that the PpAPX transcript level was very low under normal growing conditions in rd29Ap-PpAPX plants, but clearly increased under drought stress. Our results show that PpAPX does not play a significant role under normal growing conditions, but did ameliorate oxidative injury under abiotic stress. The Ad29 promoter should be used as an inducible promoter in transgenic works.
- Published
- 2009
38. Atomic Simulation of Vitrification Transformation in Mg-Cu Thin Film
- Author
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X. H. Du, J.C. Huang, M.C. Liu, H. S. Chou, C. L. Chen, C. N. Kuo, Yu-Chieh Lo, and Shin-Pon Ju
- Subjects
Atomic simulation ,Computational Mathematics ,Molecular dynamics ,Amorphous metal ,Transformation (function) ,Materials science ,Chemical engineering ,General Materials Science ,Vitrification ,General Chemistry ,Electrical and Electronic Engineering ,Thin film ,Condensed Matter Physics - Published
- 2008
39. A Modified Glass Formation Criterion for Various Glass Forming Liquids with Higher Reliability
- Author
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J.C. Huang and X. H. Du
- Subjects
chemistry.chemical_compound ,Conceptual approach ,Reliability (semiconductor) ,Amorphous metal ,Materials science ,chemistry ,Oxide ,General Physics and Astronomy ,Thermodynamics ,Liquidus ,Porous glass ,Glass transition ,Glass forming - Abstract
A modified indicator of the glass forming ability (GFA) from the previous γ = Tx/(Tl+Tg) for various glass forming liquids is proposed based on a conceptual approach which combines more acceptable physical metallurgy views in terms of the time-temperature-transformation diagrams. It is found that the glass forming ability for glass forming liquids is closely associated mainly with two factors, i.e. (2Tx−Tg) and Tl (wherein Tx is the onset crystallization temperature, Tg the glass transition temperature, and Tl the liquidus temperature), and could be predicated by a unified parameter γm defined as (2Tx−Tg)/Tl. This approach is confirmed and validated by experimental data in various glass forming systems including oxide glasses, cryoprotectants and metallic glasses, which all shows a higher reliability when their glass forming ability is predicted by the modified parameter.
- Published
- 2007
40. Compression Behavior of Mg-Cu-Gd Bulk Metallic Glasses with Various Specimen Height to Diameter Ratios
- Author
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Peter K. Liaw, X. H. Du, H. M. Chen, T. H. Hung, J.C. Huang, Jason S.C. Jang, and Y. C. Chang
- Subjects
Amorphous metal ,Materials science ,Mechanical Engineering ,Condensed Matter Physics ,Compression (physics) ,Deformation strain ,Deformation mechanism ,Mechanics of Materials ,Fracture (geology) ,General Materials Science ,Compression testing ,Composite material ,Ductility ,Shear band - Abstract
The mechanical behavior of the Mg 65 Cu 25 Gd 10 bulk metallic glasses (BMGs) in term of compression testing is reported in this study. Room-temperature compression tests are conducted on specimens with various height to diameter ratios (h/d) from 2 : 1, 1 : 1, 1 : 2, to 1 : 4. The failure strength, deformation strain, and the fracture surface morphologies are seen to vary systematically in accordance with the specimen h/d ratio. For specimens with h/d of 2 : 1 or 1 : 1, the compression response is similar to those in most reports. In contrast, for specimens with lower h/d ratios, especially at h/d = 1 : 4 (or 0.25), the shear band propagation appears to be constrained, resulting in the enhanced ductility. It suggests that different deformation mechanisms are operative for specimens with different h/d ratios. The possible deformation mechanisms in specimens of different geometries are discussed.
- Published
- 2007
41. The clinical efficacy of laparoscopy combined with choledochoscopy for cholelithiasis and choledocholithiasis
- Author
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W, Qiu, X-D, Sun, G-Y, Wang, P, Zhang, X-H, Du, and G-Y, Lv
- Subjects
Adult ,Cholangiopancreatography, Endoscopic Retrograde ,Male ,Choledocholithiasis ,Treatment Outcome ,Humans ,Cholecystectomy ,Female ,Laparoscopy ,Length of Stay ,Middle Aged - Abstract
To compare and analyze the clinical efficacy of laparoscopy combined with choledochoscopy, and laparoscopy combined with duodenoscopy, for cholelithiasis and choledocholithiasis.A total of 105 patients with cholelithiasis and choledocholithiasis from our hospital, from January 2014 to January 2015, were enrolled in this study. All patients weren given primary treatment. After obtaining consent from our hospital Ethics Committee and the patients, all 10529 cases were divided into two groups according to their time of admission. The observation group consisted of 59 cases and the control group consisted of 46 cases. The control group were treated by laparoscopy combined with duodenoscopy (cholecystectomy +ERCP+calculi extraction with an endoscope) and the observation group were treated by laparoscopy combined with choledochoscopy. We then compared the clinical efficacy between the two groups of patients.The success rate of the first surgery in the observation group, was higher than that in the control group. The time of surgery and intra-operative blood loss of the observation group were less than the control group. The differences had statistical significance p0.05). When compared the post-operative fasting and evacuation time, average hospital stay and hospitalization expenses for the observation group were less than those of the control group. The difference had statistical significance (p0.05). The prevalence of post-operative complications and recurrence rate in the observation group were statistically significantly (p0.05) less than the control group (p0.05).Laparoscopy combined with choledochoscopy was effective and safe for treating cholelithiasis and choledocholithiasis. Its treatment outcomes might be superior to laparoscopy combined with duodenoscopy.
- Published
- 2015
42. Loss mechanisms and high power piezoelectrics
- Author
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K. Uchino, J. H. Zheng, Y. H. Chen, X. H. Du, J. Ryu, Y. Gao, S. Ural, S. Priya, and S. Hirose
- Subjects
Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2006
43. Reconfiguration method for component-based network protocol
- Author
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K. C. Jin, Y. B. Bao, X. H. Du, and X. Y. Chen
- Subjects
Computer science ,business.industry ,Component (UML) ,Control reconfiguration ,Communications protocol ,business ,Computer network - Published
- 2014
44. Superplasticity and deformation mechanisms in NiAl(- Mo) alloy
- Author
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J.T. Guo, X. H. Du, and L. Z. Zhou
- Subjects
Dislocation creep ,Materials science ,Mechanical Engineering ,Metallurgy ,Superplasticity ,Strain rate ,Condensed Matter Physics ,Stress (mechanics) ,Deformation mechanism ,Mechanics of Materials ,General Materials Science ,Composite material ,Dislocation ,Deformation (engineering) ,Grain Boundary Sliding - Abstract
The mechanical behaviour and microstructural evolution in tension of NiAl-9Mo eutectic alloy at 1100degreesC and strain rates from 10(-5) to 10(-3) s(-1) have been investigated. High values of strain rate sensitivity index, but relatively small elongations between 150 and 200%, have been observed. Tensile specimens with various strains were quenched in water to preserve the dislocation structures for TEM examination. The TEM results show that the dislocation configuration and density change significantly with an increase in strain rate, and therefore correspond to different deformation mechanisms. At a low strain rate (5(.)5 x 10(-5) s(-1)), the dislocation density is relatively low and dislocation activity is regarded as an accommodation mechanism for grain boundary sliding. In contrast, the high density of dislocations as well as clear subboundaries observed in grains at a high strain rate (5(.)5 x 10(-4) s(-1)) suggest that the dislocations are active directly in response to the applied stress as well as participating in the relaxation process of grain boundary sliding by subboundary formation. Thus, grain boundary sliding is mainly responsible for superplastic deformation at a low strain rate, while superlastic deformation at a high strain rate is controlled by the combined operation of both grain boundary sliding and dynamic recovery.
- Published
- 2004
45. Liquid phase synthesis: preparation of co microspheres by hydrazine reducing method
- Author
-
Z Q Lu, Y Deng, Y J Wang, F Xie, X H Du, and H Liang
- Subjects
inorganic chemicals ,Materials science ,Reducing agent ,Hydrazine ,Halide ,chemistry.chemical_element ,Solvent ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Particle ,Hydrate ,Cobalt ,Ethylene glycol - Abstract
The study synthesizes Co microspheres with perfect spherical shape by use hydrazine hydrate as reducing agent to reduce CoCl2 in alkaline conditions at room temperature, the influence of NaOH addition amount on crystal morphology and structure of cobalt particle were studied. The results show that, under the condition of concentration of NaOH, 0.030g ml-1 and having ethylene glycol as solvent, are the best choice to synthesize Co microspheres, and the grain is smaller, suitable for industrial production. At the condition of less amount of NaOH, cobalt particle's surface is smooth spherical, and with the increase of NaOH, particles will deviate from the spherical morphology and the surface become rough. The first section in your paper
- Published
- 2017
46. Insulation characteristics of SF6/N2 gas mixtures and applied researches
- Author
-
Y. Li, R. Y. Guo, D. S. Zheng, W. Sun, and X. H. Du
- Subjects
Field (physics) ,Chemistry ,Nuclear engineering ,Electrode ,Electric breakdown ,Electronic engineering ,Range (statistics) ,Breakdown voltage ,Voltage - Abstract
SF6 is widely used in the high-voltage field as its excellent insulation performance. but now, the application of SF6 is limited to use more and more because it makes the greenhouse effect. So how to find out some gas to instead of it and how to reduce its using has become a hot issue. In this paper, the characteristics of SF6/N2 gas mixtures are investigated. considering C-GIS structural features, the experiment platform with cubicle structure was set up. The experiment electrode is a kind of rot-plane. The experiment gas pressures were set in the range 0.1-0.2 MPa. According to the results, critical breakdown voltage curves, referring to C-GIS products voltage classes, were suggested.
- Published
- 2013
47. Designing a stronger interface through graded structures in amorphous/nanocrystalline ZrCu/Cu multilayered films
- Author
-
J.C. Huang, Z. K. Wang, C H Hsueh, Chung-Hao Wang, C H Chang, X. Wang, Yu-Ju Liao, C H Hsieh, and X H Du
- Subjects
010302 applied physics ,Materials science ,Mechanical Engineering ,Bioengineering ,02 engineering and technology ,General Chemistry ,Bending ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Nanocrystalline material ,Amorphous solid ,Optical coating ,Flexural strength ,Mechanics of Materials ,0103 physical sciences ,Volume fraction ,General Materials Science ,Electrical and Electronic Engineering ,Thin film ,Composite material ,0210 nano-technology - Abstract
Many multilayered nano-structures appear to fail due to brittle matter along the interfaces. In order to toughen them, in this study, the microstructure and interface strength of multilayered thin films consisting of amorphous ZrCu and nanocrystalline Cu (with sharp or graded interfaces) are examined and analyzed. The interface possesses a gradient nature in terms of composition, nanocrystalline phase size and volume fraction. The bending results extracted from the nano-scaled cantilever bending samples demonstrate that multilayered films with graded interfaces would have a much higher interface bending strength/strain/modulus, and an overall improvement upgrade of more than 50%. The simple graded interface design of multilayered thin films with improved mechanical properties can offer much more promising performance in structural and functional applications for MEMS or optical coating.
- Published
- 2016
48. Improving an SVM-based Liver Segmentation Strategy by the F-score Feature Selection Method
- Author
-
Qinxue Hu, X. H. Du, Pheng-Ann Heng, Jia Liu, Yizhuang Xu, and Z. J. Chen
- Subjects
Support vector machine ,Region growing ,Computer science ,business.industry ,Principal component analysis ,Pattern recognition ,Feature selection ,Segmentation ,Artificial intelligence ,F1 score ,business ,Classifier (UML) ,Thresholding - Abstract
A fast and accurate computer-aided liver segmentation plays a vital role in the virtual hepatic surgery. Large amount of features yielded in supervised segmentation methods may lead to slow training and classifying processes. Therefore, feature selection is of importance in order to speed up the liver segmentation. Recently, a hybrid method was proposed by Liu et al. combining thresholding, classifier and region growing. However, this method suffers from long process time caused by the large amount of features. F-score is a simple technique to measure the discrimination of different features. We therefore combine F-score to the hybrid method to reduce the time required in the training and testing stage.
- Published
- 2009
49. Atomic structure evolution of Zr-Ni during severe deformation by HA pair analysis
- Author
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X. H. Du, Shin-Pon Ju, Yu-Chieh Lo, and J.C. Huang
- Subjects
Materials science ,Condensed matter physics ,Alloy ,engineering.material ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Condensed Matter::Materials Science ,Molecular dynamics ,Orders of magnitude (time) ,Pairing ,Atom ,engineering ,Deformation (engineering) ,Severe plastic deformation ,Mixing (physics) - Abstract
The gradual vitrification evolution of atom mixing and local atomic pairing structure of the binary Zr-Ni alloy during severe deformation at room temperature is traced numerically by molecular dynamic simulation. It is found that the icosahedra clusters will gradually develop with the increasing of disorder environment of alloys. Other compoundlike transition structures were also observed in transient in the Zr-Ni couple during the solid-state amorphization process under severe plastic deformation. Since the time scale of the molecular dynamic simulation is several orders of magnitude shorter than reality, the simulated atomic evolution can be viewed as that would occur at ultrahigh strain rates.
- Published
- 2007
50. [Topological research of Kováts indices for amines]
- Author
-
C J, Feng and X H, Du
- Subjects
Chromatography ,Models, Chemical ,Quantitative Structure-Activity Relationship ,Amines - Abstract
A novel connectivity index(mQ) is defined as mQ = sigma (ti.tj.tk....)-0.5 in this paper. 0Q and 3Q have very good correlation for Kováts indices of 22 amines on three stationary phases(OV-101, OV-225 and NGA). Their linear regression equations are proposed as follows: IOV-101 = 118.341 + 197.854 x 0Q + 448.773 x 3Q, r = 0.9733; IOV-225 = 249.218 + 1,815.760 x 3Q + 343.222 x 1Q, r = 0.9746; INGA = 382.196 + 2,004.277 x 3Q + 318.416 x 1Q, r = 0.9734. These models can better elucidate the change rule of Kováts indices for the amines. Furthermore, a modified Jackknife's test was performed to validate the model robustness.
- Published
- 2003
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