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      • KCI등재

        DNA methylation and mRNA expression of COL6A3 in antler mesenchyme of female and male reindeer

        JianCheng Zhai,Ruo‑Bing Han,Sheng‑Nan Wang,Qiang‑Hui Wang,Yan‑Ling Xia,Wei‑Shi Liu,Ya‑Jie Yin,He‑Ping Li 한국유전학회 2019 Genes & Genomics Vol.41 No.9

        Backgroud Reindeer is the only deer species that both male and female produce antlers, which provides a particularly interesting case in studying the differences between antlers of the two sexes. Alpha 3(VI) Collagen Gene (COL6A3), forms a microfibrillar network associated with the structural integrity and biomechanical properties, has been found to be one of the differentially expressed genes in antler mesenchyme of female and male reindeer. Objective and Methods The promoter sequence of reindeer COL6A3 gene was obtained using the cloning technology and analyzed by the bioinformatics methods. Bisulfite sequencing PCR (BSP) was used to detect the methylation status of the COL6A3 promoter in reindeer antler mesenchyme. Real-time quantitative PCR was used to detect COL6A3 expression in the antler mesenchyme of female and male reindeer. Results Sequence analysis revealed that the reindeer COL6A3 partial promoter sequence was 983 bp including the possible promoter region at + 105 bp to + 155 bp. Homology and phylogenetic analysis indicated that the COL6A3 promoter of reindeer had the closest genetic distance with Bos taurus, Capra hircus and Ovis aries. BSP results indicated that the methylation level of COL6A3 promoter in the female reindeer antler mesenchyme was significantly higher than in the male. Correlating with increased methylation status, we also found that COL6A3 mRNA expression in female reindeer antler mesenchyme was significantly lower than in the male. Conclusion The higher methylation level of the COL6A3 gene in female reindeer antler mesenchyme coincides with decreased COL6A3 mRNA expression, thereby affecting the transposon silencing mechanism and possibly contributing to apparent differences of antlers in female and male reindeer.

      • Implications for new physics from <sup>B¯0</sup>→<sup>π0</sup><sup>π0</sup> and <sup>B¯0</sup>→<sup>K¯0</sup><sup>K0</sup>

        Cheng, Jian-Feng,Gao, Yuan-Ning,Huang, Chao-Shang,Wu, Xiao-Hong Elsevier 2006 Physics letters: B Vol.637 No.4

        <P><B>Abstract</B></P><P>We have analyzed the <SUP>B¯0</SUP>→<SUP>π0</SUP><SUP>π0</SUP> puzzle in three kinds of models beyond the standard model (SM). It is shown that the minimal flavor violation (MFV) models, the minimal supersymmetric standard model (MSSM), and the two Higgs doublet models (2HDM) I and II cannot give an explanation of the <SUP>B¯0</SUP>→<SUP>π0</SUP><SUP>π0</SUP> puzzle within 1<I>σ</I> experimental bounds and the model III 2HDM can explain the puzzle without a conflict with other experimental measurements. If the constraint on <SUB>C8g</SUB> from b→sg is not imposed, for all kinds of insertions considered there are regions of parameter space, where the scalar quark mass is larger (much larger) than the gluino mass in the case of <I>LR</I> or <I>RL</I> (<I>LL</I> or <I>RR</I>), in which the puzzle can be resolved within 1<I>σ</I> experimental bounds.</P>

      • KCI등재

        Effect of hanging-type sand fence on characteristics of wind-sand flow fields

        Jian-jun Cheng,Jia-qiang Lei,Sheng-yu Li,Hai-feng Wang 한국풍공학회 2016 Wind and Structures, An International Journal (WAS Vol.22 No.5

        A hanging-type sand-retaining wall is a very common sand-blocking fence structure used to prevent sand movement. This type of wall is widely used along the Qinghai–Tibet and Gobi desert railways in Xinjiang, Western China. To analyze the characteristics of wind-sand flow fields under the effect of such a sand fence structure, a wind tunnel test and a field test were carried out. The wind tunnel test showed the zoning characteristics of the flow fields under the effect of the hanging-type sand-retaining wall, and the field test provided the sediment transport data for effective wind-proof interval and the sand resistance data in the front and behind the sand-retaining wall. The consistency of the wind-sand flow fields with the spatial distribution characteristic of wind-carried sand motion was verified by the correspondences of the acceleration zone in the flow field and the negative elevation points of the percentage variations of the sand collection rate. The spatial distribution characteristic of the field sand collection data further showed the spatial structural characteristic of the sandy air currents under the action of the hanging-type sand-retaining wall and the sand resistance characteristic of the sand-retaining wall. This systematic study on the wind-sand flow fields under the control of the hanging-type sand-retaining wall provides a theoretical basis for the rational layout of sand control engineering systems and the efficient utilization of a hanging-type sand-retaining wall.

      • KCI등재

        Field Emission from TiO2/Ti Nanotube Array Films Modified with Carbon Nanotubes

        Cheng-Wei Wang,Rui-Sheng Guo,Jian-Biao Chen,Yan Li,Jian Wang,Wei-Min Liu 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

        Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter. Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter.

      • SCIESCOPUS

        Effect of hanging-type sand fence on characteristics of wind-sand flow fields

        Cheng, Jian-jun,Lei, Jia-qiang,Li, Sheng-yu,Wang, Hai-feng Techno-Press 2016 Wind and Structures, An International Journal (WAS Vol.22 No.5

        A hanging-type sand-retaining wall is a very common sand-blocking fence structure used to prevent sand movement. This type of wall is widely used along the Qinghai-Tibet and Gobi desert railways in Xinjiang, Western China. To analyze the characteristics of wind-sand flow fields under the effect of such a sand fence structure, a wind tunnel test and a field test were carried out. The wind tunnel test showed the zoning characteristics of the flow fields under the effect of the hanging-type sand-retaining wall, and the field test provided the sediment transport data for effective wind-proof interval and the sand resistance data in the front and behind the sand-retaining wall. The consistency of the wind-sand flow fields with the spatial distribution characteristic of wind-carried sand motion was verified by the correspondences of the acceleration zone in the flow field and the negative elevation points of the percentage variations of the sand collection rate. The spatial distribution characteristic of the field sand collection data further showed the spatial structural characteristic of the sandy air currents under the action of the hanging-type sand-retaining wall and the sand resistance characteristic of the sand-retaining wall. This systematic study on the wind-sand flow fields under the control of the hanging-type sand-retaining wall provides a theoretical basis for the rational layout of sand control engineering systems and the efficient utilization of a hanging-type sand-retaining wall.

      • SCIESCOPUS

        Ultimate behavior of long-span steel arch bridges

        Cheng, Jin,Jiang, Jian-Jing,Xiao, Ru-Cheng,Xiang, Hai-Fan Techno-Press 2002 Structural Engineering and Mechanics, An Int'l Jou Vol.14 No.3

        Because of the increasing span of arch bridges, ultimate capacity analysis recently becomes more focused both on design and construction. This paper investigates the static and ultimate behavior of a long-span steel arch bridge up to failure and evaluates the overall safety of the bridge. The example bridge is a long-span steel arch bridge with a 550 m-long central span under construction in Shanghai, China. This will be the longest central span of any arch bridge in the world. Ultimate behavior of the example bridge is investigated using three methods. Comparisons of the accuracy and reliability of the three methods are given. The effects of material nonlinearity of individual bridge element and distribution pattern of live load and initial lateral deflection of main arch ribs as well as yield stresses of material and changes of temperature on the ultimate load-carrying capacity of the bridge have been studied. The results show that the distribution pattern of live load and yield stresses of material have important effects on bridge behavior. The critical load analyses based on the linear buckling method and geometrically nonlinear buckling method considerably overestimate the load-carrying capacity of the bridge. The ultimate load-carrying capacity analysis and overall safety evaluation of a long-span steel arch bridge should be based on the geometrically and materially nonlinear buckling method. Finally, the in-plane failure mechanism of long-span steel arch bridges is explained by tracing the spread of plastic zones.

      • FEM analysis of the modular prefabricated steel-concrete composite beam-column internal joint under reciprocating action

        Cheng Long Wu,Jian Cheng Kan,Qi Hui Wang,Ji Ming Liu,Zun Qiang Li 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.41 No.1

        Prefabricated steel-concrete composite structure has the advantages of large bearing capacity, reliable connection, and good durability, which is of great significance to the development of building industrialization. In this paper, a finite element model (FEM) of the modular prefabricated SRC column-steel beam composite joint is established and verified its accuracy through ABAQUS. The effects of various parameter variables on the hysteresis curve, skeleton curve, ductility, energy consumption, and performance deterioration are investigated. The results show that as the axial compression ratio increases, the joint bearing capacity first increases and then decreases, the strength and stiffness have relatively stable degradation characteristics. However, the hysteresis curve has a certain “pinch” phenomenon, which reduces the energy consumption performance. Different column end bolts margin and apertures have little effect on the bearing capacity, strength and stiffness degradation performance, but affect energy consumption and ductility. The width-to-thickness ratio of the square steel tube has a greater impact on the bearing capacity, energy consumption and ductility, and has less impact on the strength and stiffness degradation performance. As the thickness of the joint cover plate increases, the bearing capacity, energy consumption and initial stiffness of the joint gradually increase, the ductility first increases and then decreases.

      • Relationship Between PTEN and Livin Expression and Malignancy of Renal Cell Carcinomas

        Cheng, Tao,Zhang, Jian-Guo,Cheng, Yuan-He,Gao, Zhong-Wei,Ren, Xiao-Qiang Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

        Objectives: This study focused on PTEN and Livin expression and associations with malignancy in human renal clear cell carcinomas (RCCC). Methods: PTEN and Livin expression was assessed in 100 RCCC tissue samples, 50 paracarcinoma cases, and 20 normal renal tissue samples using the immunohistochemical Streptavidin proxidase (SP) method. The relationships between binding and corresponding biological characteristics, such as histological grade, lymph node metastases, and clinical stages were analyzed. Results: Positive PTEN expression in RCCC was significantly lower than in renal tissue adjacent to carcinoma tissue and normal renal tissue (P<0.01). Livin expression in the renal tissue adjacent to the carcinoma and normal renal tissues exhibited only low levels, whereas overall Livin expression in RCCC was statistically significant (P<0.01). In RCCC, PTEN expression rate gradually decreased with an increase in clinical stage, whereas that of Livin increased to statistically significant levels (P<0.01), PTEN and Livin levels being negatively correlated (r=-0.395, P<0.01). Conclusions: PTEN and Livin are important in RCCC development. The two factors combined are expected to provide indices for estimating RCCC malignancy and progression levels, as well as references for RCCC diagnosis and treatment.

      • SCIESCOPUS

        Probabilistic determination of initial cable forces of cable-stayed bridges under dead loads

        Cheng, Jin,Xiao, Ru-Cheng,Jiang, Jian-Jing Techno-Press 2004 Structural Engineering and Mechanics, An Int'l Jou Vol.17 No.2

        This paper presents an improved Monte Carlo simulation for the probabilistic determination of initial cable forces of cable-stayed bridges under dead loads using the response surfaces method. A response surface (i.e. a quadratic response surface without cross-terms) is used to approximate structural response. The use of the response surface eliminates the need to perform a deterministic analysis in each simulation loop. In addition, use of the response surface requires fewer simulation loops than conventional Monte Carlo simulation. Thereby, the computation time is saved significantly. The statistics (e.g. mean value, standard deviation) of the structural response are calculated through conventional Monte Carlo simulation method. By using Monte Carlo simulation, it is possible to use the existing deterministic finite element code without modifying it. Probabilistic analysis of a truss demonstrates the proposed method' efficiency and accuracy; probabilistic determination of initial cable forces of a cable-stayed bridge under dead loads verifies the method's applicability.

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