• 제목/요약/키워드: Peking

검색결과 470건 처리시간 0.028초

Morphological Characteristics of Hyphal Interaction between Grifola umbellata and its Companion Fungus

  • Xing, Xiao-Ke;Guo, Shun-Xing;Lee, Min-Woong
    • Mycobiology
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    • 제33권1호
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    • pp.1-6
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    • 2005
  • Morphological characteristics of hyphal interaction between Grifola umbellata (Pers. Ex Fr.) Pilat and its companion fungus which related to sclerotia formation from hyphae were investigated by external observations, light microscopy and transmission electron microscopy (TEM). External observations showed that a dense antagonism line was formed by both G. umbellata and companion fungus after their hyphae contacted each other in dual culture. Many hyphal strands emerged on the colony of G. umbellata and differentiated to sclerotia from where hyphal strands crossed. Light microscope observations revealed the process of antagonism line formation. Mature antagonism with structural differentiation, was composed of three main layers: the rind, the rind underlayer and the hypha layer. TEM observations showed that after colonies hyphal contact, a series of reactions always occurred in both G. umbellata and companion fungus. Cells in the center of antagonism line were dead. Cells of G. umbellata adjacent to the antagonism line were usually large and hollow, with unilateral thickened wall, whereas those of companion fungus were empty, with thin or thick wall. Both hyphal interaction at the antagonism line may be one of the main reasons for sclerotia of G. umbellata differentiation from hypha.

Study of the Effects of the Antisite Related Defects in Silicon Dioxide of Metal-Oxide-Semiconductor Structure on the Gate Leakage Current

  • Mao, Ling-Feng;Wang, Zi-Ou;Xu, Ming-Zhen;Tan, Chang-Hua
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제8권2호
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    • pp.164-169
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    • 2008
  • The effects of the antisite related defects on the electronic structure of silica and the gate leakage current have been investigated using first-principles calculations. Energy levels related to the antisite defects in silicon dioxide have been introduced into the bandgap, which are nearly 2.0 eV from the top of the valence band. Combining with the electronic structures calculated from first-principles simulations, tunneling currents through the silica layer with antisite defects have been calculated. The tunneling current calculations show that the hole tunneling currents assisted by the antisite defects will be dominant at low oxide field whereas the electron direct tunneling current will be dominant at high oxide field. With increased thickness of the defect layer, the threshold point where the hole tunneling current assisted by antisite defects in silica is equal to the electron direct tunneling current extends to higher oxide field.

Annexin A2 and CD105 Expression in Pancreatic Ductal Adenocarcinoma is Associated with Tumor Recurrence and Prognosis

  • Huang, Ya-Kai;Liu, Hong;Wang, Xin-Zheng;Zhu, Shan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권22호
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    • pp.9921-9926
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    • 2014
  • To investigate the value of expression of annexin A2, microvessel density (MVD) and CD105 in pancreatic ductal adenocarcinoma (PDAC) tissues and adjacent normal tissues, immunohistochemical staining was used. The positive expression rate of Annexin A2 and the MVD in pancreatic ductal adenocarcinoma tissues was higher than that in in adjacent normal tissues (p<0.005). Expression of Annexin A2 and MVD correlated with histological grade (p<0.05). MVD of cancers in TNM stage IIb was higher than that in TNM stageI~IIa (p<0.026). Cancerous tissues with Annexin A2 staining grade 3+ had lower MVD than the tissues with the other Annexin A2 staining grade (p<0.05). Patients with high MVD had worse prognosis. However, our study did not confirm Annexin A2 was an independent risk factor for patients with PDAC. We confirmed MVD labeled by CD105 was an independent risk factor for patients with PDAC and had moderate predictive value of prognosis.

One-Year Continuous Measurement of Outdoor Radon Progeny Concentration in Beijing Area

  • Zhang, Lei;Wang, Yunxiang;Guo, Qiuju
    • Journal of Radiation Protection and Research
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    • 제45권3호
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    • pp.95-100
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    • 2020
  • Background: Compared with reported data of radon concentration, data of radon progeny concentration is limited in general, especially in outdoor environment. Materials and Methods: To know both the level and the variation of radon progeny concentration in outdoor environment in Beijing area, one-year continuous measurement with a cycle of 60 minutes was carried out by a step-advanced filter (SAF) monitor for radon progeny measurement. The observation site was located in a park in Eastern Beijing area, and the observation period was from October 17, 2018 to September 29, 2019. Results and Discussion: The equivalent equilibrium concentration (EEC) of radon progeny varies from 0.7 to 19.1 Bq·m-3, with an annual average of 4.9 ± 2.7 Bq·m-3. A clear diurnal variation of EEC, higher in the early morning and lower in the late afternoon, is observed due to the high sensitivity of the SAF monitor. Conclusion: Vertical convection of atmospheric boundary layer is thought to be the main reason of this phenomenon. For annual variation, the lowest monthly average EEC appeared in April, while the highest appeared in November, which might attribute to the atmospheric stability in different seasons.

Common Genetic Variations in the MUC5AC Gene are Not Related to Helicobacter pylori Serologic Status

  • Zhou, Cheng-Jiang;Zhang, Liu-Wei;Gao, Fang;Zhang, Bin;Wang, Ying;Chen, Da-Fang;Jia, Yan-Bin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권24호
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    • pp.10719-10722
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    • 2015
  • Several lines of evidence suggest that MUC5AC genetic polymorphisms might confer susceptibility to H. pylori infection and therefore gastric cancer risk. We here assessed the association of common polymorphisms in the MUC5AC gene with H. pylori seroprevalence using an LD-based tagSNP approach in a north-western Chinese Han population. A total of 12 tagSNPs were successfully genotyped among 281 unrelated ethnic Han Chinese who had no cancer history, and no identifiable gastric disease or genetic disease. No significant association between any alleles, genotypes or haplotypes and H. pylori seroprevalence was observed. Our results suggest that common genetic variations in MUC5AC gene might not make a major contribution to the risk of H. pylori infection.

Identification of nucleolar and coiled-body phosphoprotein 1 (NOLC1) minimal promoter regulated by NF-κB and CREB

  • Gao, Xuesong;Wang, Qi;Li, Wei;Yang, Biao;Song, Hao;Ju, Wei;Liu, Shunai;Cheng, Jun
    • BMB Reports
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    • 제44권1호
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    • pp.70-75
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    • 2011
  • Nucleolar and coiled-body phosphoprotein 1 (NOLC1) is a phosphoprotein that transiently associates with the mature nucleolar H/ACA and C/D box small nucleolar ribonucleoproteins (snoRNPs). Several lines of evidence indicate that NOLC1 plays an important role in the synthesis of rRNA and the biosynthesis of ribosomes. In the present study, we examined the transcriptional regulation mechanisms that govern the expression of NOLC1. We first performed functional dissection of the NOLC1 promoter. We demonstrated that transcription factors NF-${\kappa}B$ and CREB could bind to the minimal NOLC1 promoter. This was demonstrated by electrophoretic mobility shift assays and chromatin immunoprecipitation. Mutagenesis and overexpression assays revealed that NF-${\kappa}B$ and CREB positively regulated the NOLC1 promoter. These findings may provide new insight into the mechanisms that regulate NOLC1 expression.

The Throughput Order of Multicast Traffics with Physical-Layer Network Coding in Random Wireless Ad Hoc Networks

  • Chen, Chen;Bai, Lin;He, Jianhua;Xiang, Haige;Choi, Jin-Ho
    • Journal of Communications and Networks
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    • 제13권3호
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    • pp.214-220
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    • 2011
  • This paper attempts to address the effectiveness of physical-layer network coding (PNC) on the throughput improvement for multi-hop multicast in random wireless ad hoc networks (WAHNs). We prove that the per session throughput order with PNC is tightly bounded as ${\Theta}((n\sqrt{m}R(n))^{-1})$ if $m=(R^{-2}(n))$, where n is the total number of nodes, R(n) is the communication range, and m is the number of destinations for each multicast session. We also show that per-session throughput order with PNC is tight bounded as ${\Theta}(n^{-1})$, when $m={\Omega}(R^{-2}(n))$. The results of this paper imply that PNC cannot improve the throughput order of multicast in random WAHNs, which is different from the intuition that PNC may improve the throughput order as it allows simultaneous signal access and combination.

A Lightweight Integrity Authentication Scheme based on Reversible Watermark for Wireless Body Area Networks

  • Liu, Xiyao;Ge, Yu;Zhu, Yuesheng;Wu, Dajun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권12호
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    • pp.4643-4660
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    • 2014
  • Integrity authentication of biometric data in Wireless Body Area Network (WBAN) is a critical issue because the sensitive data transmitted over broadcast wireless channels could be attacked easily. However, traditional cryptograph-based integrity authentication schemes are not suitable for WBAN as they consume much computational resource on the sensor nodes with limited memory, computational capability and power. To address this problem, a novel lightweight integrity authentication scheme based on reversible watermark is proposed for WBAN and implemented on a TinyOS-based WBAN test bed in this paper. In the proposed scheme, the data is divided into groups with a fixed size to improve grouping efficiency; the histogram shifting technique is adopted to avoid possible underflow or overflow; local maps are generated to restore the shifted data; and the watermarks are generated and embedded in a chaining way for integrity authentication. Our analytic and experimental results demonstrate that the integrity of biometric data can be reliably authenticated with low cost, and the data can be entirely recovered for healthcare applications by using our proposed scheme.

Human HS1BP3 induces cell apoptosis and activates AP-1

  • Shi, Taiping;Xie, Jieshi;Xiong, Ying;Deng, Weiwei;Guo, Jinhai;Wang, Feng;Ma, Dalong
    • BMB Reports
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    • 제44권6호
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    • pp.381-386
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    • 2011
  • In the present study, we characterized the function of HS1-binding protein 3 (HS1BP3), which is mutated in essential tremor and may be involved in lymphocyte activation. We found that HS1BP3 localized to the mitochondria and endoplasmic reticulum partially. Overexpression of HS1BP3 induced apoptosis in HEK293T and HeLa cell lines. When these cell lines were transfected with HS1BP3, they exhibited nuclear DNA condensation, externalization of phosphatidylserine (PS), and cleavage of poly ADP ribose polymerase (PARP). Furthermore, suppression of HS1BP3 or HS1 expression attenuates HS1BP3 induced apoptosis. In addition, HS1BP3 enhanced activator protein 1 (AP-1)-mediated transcription in a dose-dependent manner. Therefore, we conclude that HS1BP3 regulates apoptosis via HS1 and stimulates AP-1-mediated transcription.