Promoter Analysis of Bombyx mori Nucleopolyhedrovirus Ubiquitin Gene

Xu’ai Lin,Yin Chen,Yongzhu Yi,Jie Yan,Zhifang Zhang 한국미생물학회 2008 The journal of microbiology Vol.46 No.4

The aim of this study was to analyze the characteristics of Bombyx mori nucleopolyhedrovirus (BmNPV) ubiquitin gene promoter and the effects of conserved motifs, such as TAAG, TATA, and CAAT, along with baculovirus enhancer homologous region 3 (hr3), on promoter activity. Ubiquitin gene of BmNPV was expressed during the late phase of virus infection. In the presence of viral factors, significant reduction of promoter activity was observed by deletion of -382 to -124 bp upstream of ATG. The fragment between -187 and -383 bp upstream of ATG, including distal TAAG, CAAT motif, and TATA box, could also drive expression of the reporter gene. The mutation of cis-elements TATA boxes and TAAG motifs significantly decreased the promoter’s activity, while CAAT mutations enhanced promoter activity by 2- or 3-fold, as compared with the native promoter. In the presence of BmNPV, hr3, both located downstream of the reporter gene of the same vector, and separate vector, could significantly enhance transcription activity of ubiquitin promoter as compared to the control. We concluded that BmNPV ubiquitin gene might be regulated by dual sets of promoter elements, where TAAG and TATA box may positively regulate the expression of ubiquitin, while CAAT motif functions as a negative regulator. Viral factor(s) play an important role in the co-activation of hr3 and promoter.

Effect of local wall thinning on ratcheting behavior of pressurized 90° elbow pipe under reversed bending using finite element analysis

Xiaohui Chen,Xu Chen 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.20 No.4

Ratcheting deformation of pressurized Z2CND18.12N stainless steel 90° elbow pipe with local wall thinning subjected to constant internal pressure and reversed bending was studied using finite element analysis. Chen-Jiao-Kim (CJK) kinematic hardening model, which was used to simulate ratcheting behavior of pressurized 90° elbow pipe with local wall thinning at extrados, flanks and intrados, was implemented into finite element software ANSYS. The local wall thinning was located at extrados, flanks and intrados of 90° elbow pipe, whose geometry was rectangular cross-section. The effect of depth, axial length and circumferential angle of local wall thinning at extrados, flanks and intrados on the ratcheting behaviors of 90° elbow pipe were studied in this paper. Threedimensional elastic-plastic analysis with Chen-Jiao-Kim (CJK) kinematic hardening model was carried out to evaluate structural ratcheting behaviors. The results indicated that ratcheting strain was generated mainly along the hoop direction, while axial ratcheting strain was relatively small.

Comparative Analysis of Post-editing Techniques for Chinese-to-English Translation Tasks: A Quasi-Experimental Study

Chen Xu(Chen Xu ),신유선(Yousun Shin) 한국영미어문학회 2023 영미어문학 Vol.- No.149

This study aimed to examine the differences in translation time and quality between human translation (HT), machine translation post-editing (MTPE), and ChatGPT post-editing (ChatGPT PE). A quasi-experimental design was employed, involving 30 junior participants majoring in English from a Chinese university. A translation task consisting of 532 words from Chinese to English was assigned to the three groups and the translation speed and quality were assessed using the Multidimensional Quality Metrics (MQM) and Dynamic Quality Framework (DQF). The results demonstrated that the post-editing technique could produce translation quality comparable to human translation while achieving faster translation speed. It was observed that ChatGPT PE outputs exhibited the highest number of terminology errors but had the fewest accuracy errors, while mean differences in two of accuracy dimensions were observed among the three groups. The utilization of post-editing in language teaching would allow for the integration of machine translation strengths and human expertise, resulting in high-quality translations on par with human translations. To optimize post-editing outcomes, it is crucial to develop and teach error-detection techniques and avoid excessive reliance on AI technology.

Knocking Down Nucleolin Expression Enhances the Radiosensitivity of Non-Small Cell Lung Cancer by Influencing DNA-PKcs Activity

Xu, Jian-Yu,Lu, Shan,Xu, Xiang-Ying,Hu, Song-Liu,Li, Bin,Qi, Rui-Xue,Chen, Lin,Chang, Joe Y. Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

Nucleolin (C23) is an important anti-apoptotic protein that is ubiquitously expressed in exponentially growing eukaryotic cells. In order to understand the impact of C23 in radiation therapy, we attempted to investigate the relationship of C23 expression with the radiosensitivity of human non-small cell lung cancer (NSCLC) cells. We investigated the role of C23 in activating the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), which is a critical protein for DNA double-strand breaks (DSBs) repair. As a result, we found that the expression of C23 was negatively correlated with the radiosensitivity of NSCLC cell lines. In vitro clonogenic survival assays revealed that C23 knockdown increased the radiosensitivity of a human lung adenocarcinoma cell line, potentially through the promotion of radiation-induced apoptosis and adjusting the cell cycle to a more radiosensitive stage. Immunofluorescence data revealed an increasing quantity of ${gamma}$-H2AX foci and decreasing radiation-induced DNA damage repair following knockdown of C23. To further clarify the mechanism of C23 in DNA DSBs repair, we detected the expression of DNA-PKcs and C23 proteins in NSCLC cell lines. C23 might participate in DNA DSBs repair for the reason that the expression of DNA-PKcs decreased at 30, 60, 120 and 360 minutes after irradiation in C23 knockdown cells. Especially, the activity of DNA-PKcs phosphorylation sites at the S2056 and T2609 was significantly suppressed. Therefore we concluded that C23 knockdown can inhibit DNA-PKcs phosphorylation activity at the S2056 and T2609 sites, thus reducing the radiation damage repair and increasing the radiosensitivity of NSCLC cells. Taken together, the inhibition of C23 expression was shown to increase the radiosensitivity of NSCLC cells, as implied by the relevance to the notably decreased DNA-PKcs phosphorylation activity at the S2056 and T2609 clusters. Further research on targeted C23 treatment may promote effectiveness of radiotherapy and provide new targets for NSCLC patients.

Discovery of Anticostia uniformis from the Xiazhen Formation at Zhuzhai, South China and its stratigraphic implication

Chen, Zhong-Yang,Kim, Myong-Hak,Choh, Suk-Joo,Lee, Dong-Jin,Chen, Xu Elsevier 2016 Palaeoworld Vol.25 No.3

<P>The Xiazhen Formation is an Upper Ordovician lithostratigraphic unit in the Jiangshan-Changshan-Yushan (JCY) area, which contains series of Late Ordovician reef successions. The reef successions of the Xiazhen Formation at Zhuzhai are critical for evaluation of the Late Ordovician marine diversity and palaeoecology. However, their age has long been uncertain and generally is regarded as of upper Katian, based on the occurrences of shelly fossils and correlation with the stratigraphic equivalent Changwu Formation. The newly discovered graptolite species Anticostia uniformis, in the Xiazhen Formation, together with the combined evidence of brachiopods and sedimentology, indicates an age range for the graptolite locality from the Dicellograptus complanatus Biozone to the Diceratograptus mirus Subzone of late Katian, but the graptolites do not rule out the possibility that it is Hirnantian. (C) 2015 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. All rights reserved.</P>

Influence of Illumination with Xenon or Sulfur Lamp on Growth of Tomato Seedlings

Chen, Qilin,Yu, Xinjian,Weng, Jun,Chen, Jinxing,Liu, Yuequn,Gao, Jinpeng,Xu, Chunhe Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

Effects of illumination with xenon or sulfur lamp on growth of tomato seedlings were studied. Results showed no obvious differences in net photosynthetic rate and apparent quantum efficiency. In comparison with xenon lamp, illumination with sulfur lamp slightly reduced ChI a and ChI b content in leaves, relatively shortened epicotyl and hypocotyl length, but significantly increased anthocyanin content of leaves and promoted root growth of tomato seedling plants.

Avoid Umbrella, Just for Good

Xu Chen 한국콘텐츠학회 2017 ICCC International Digital Design Invitation Exhib Vol.2017 No.8

Evolution of Microstructures and Compressive Properties in Al0.5CrFeNi2.1Mn0.8Tix High Entropy Alloys

Xu Chen,Di Gao,Yan Zhang,Jia Xuan Hu,Ye Liu,Feng Xiang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.1

The effects of Ti on the microstructures, macrohardness and compressive properties of the as-cast Al0.5CrFeNi2.1Mn0.8TixHEAs were investigated. The results showed that the microstructures of as-cast Al0.5CrFeNi2.1Mn0.8Tixalloys was changedfrom FCC phase to a mixture of FCC and BCC phases, then to a mixture of BCC phase and Ti-containing intermetalliccompound as the increasing of Ti content. Chrysanthemum-like eutectic microstructure was obtained in theAl0.5CrFeNi2.1Mn0.8Ti0.5and Al0.5CrFeNi2.1Mn0.8Tialloys. The area of flower core was composed of BCC2 phase, andeutectic microstructure was achieved in the petal area which contained BCC1 phase and BCC2 phase. Moreover, the macrohardnessof the as-cast alloys increased with the increasing of Ti, and the Al0.5CrFeNi2.1Mn0.8Ti0.5alloy showed excellentcomprehensive compressive properties.

Quantitative Assessment of the Association between ABC Polymorphisms and Osteosarcoma Response: a Meta-analysis

Chen, Xu,Jiang, Min,Zhao, Rui-Ke,Gu, Guo-Hao Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Background: ABC proteins are one key type of transport superfamilies which undertake majority of drug transport, which affect the osteosarcoma response to chemotherapeutics. Previous studies have suggested the association between ABC polymorphisms and osteosarcoma response. However, the results of previous studies remain controversial. Therefore, we perform a meta-analysis to get a more precise estimation of this association. The association between ABC polymorphisms and osteosarcoma response was assessed by odds ratios (ORs) together with their 95% confidence intervals (CIs). Three polymorphisms of ABC including ABCB1 rs1128503, ABCC3 rs4148416 and ABCC2 rs717620 polymorphism were investigated. Overall, significant association was observed between ABCC3 rs4148416 polymorphism and osteosarcoma response under allele contrast (T vs. C: OR=1.73, 95%CI=1.09-2.74, P=0.019), homozygote comparison (TT vs. CC: OR=2.00, 95%CI=1.25-3.23, P=0.004), recessive genetic model (TT vs. TC/CC: OR=1.80, 95%CI=1.14-2.84, P=0.011) and dominant genetic model (TT/TC vs. CC: OR=1.70, 95%CI=1.20-2.42, P=0.003). Moreover, significant association was also observed in Caucasian population rather than Asian population for ABCB1 rs1128503 polymorphism. We conclude that ABCC3 rs4148416 polymorphism was significantly associated with poor osteosarcoma response and ABCB1 rs1128503 polymorphism was significantly associated with good osteosarcoma response in Caucasian population rather than Asian population.

A Cross-domain Authentication Method for Cloud Computing

Chen Xu,Jingsha He 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.3

The use of security certificates under the Cloud environment is the foundation to establish mutual trust between the Cloud and the user. In this paper, we propose an authentication method based on zero-knowledge proof and the mind of key escrow. With the method, authentication will not only satisfy the requirement anonymity and security but also can recover the real identity information in special circumstances with the cooperation of multiple parties. We will show that this proposed method is more suitable for promotion through analysis and comparison with an existing scheme.