Poster Session : Purification and characterization of NADH oxidase from Thermococcus profundus

( Bo Lei Jia ),( Seong Cheol Park ),( Yong Gi Shao ),( Gang Won Cheong ) 한국생화학분자생물학회 (구 한국생화학회) 2006 생화학분자생물학회 춘계학술발표논문집 Vol.2006 No.-

Bioactive glass microspheres as reinforcement for improving the mechanical properties and biological performance of poly(ε‐caprolactone) polymer for bone tissue regeneration

Lei, Bo,Shin, Kwan‐,Ha,Noh, Da‐,Young,Koh, Young‐,Hag,Choi, Won‐,Young,Kim, Hyoun‐,Ee Wiley Subscription Services, Inc., A Wiley Company 2012 Journal of Biomedical Materials Research Part B Vol. No.

<P><B>Abstract</B></P><P>This study examined the utility of sol–gel‐derived bioactive glass microspheres (BGMs) as a reinforcement to improve the mechanical properties and biological performance of poly(ε‐caprolactone) (PCL) polymer. All of the PCL‐BGMs composites produced, with a variety of BGMs contents (10, 20, and 30 wt %), showed a uniform distribution of the BGMs in the PCL matrix, particularly owing to their spherical shape and small size. This led to a considerable increase in the elastic modulus from 93 ± 12 MPa to 635 ± 179 MPa with increasing BGMs content from 0 to 30 wt %. Furthermore, the addition of the BGMs to the PCL polymer significantly increased the hydrophilicity of the PCL‐BGMs composites, which led to a higher water absorption and degradation rate. The PCL‐BGMs composite with a BGMs content of 30 wt % showed vigorous growth of apatite crystals with a high aspect ratio on its surface after soaking in the simulated body fluid for 7 days, resulting in the creation of a porous carbonate hydroxyapatite layer. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.</P>

Nanofibrous gelatin–silica hybrid scaffolds mimicking the native extracellular matrix (ECM) using thermally induced phase separation

Lei, Bo,Shin, Kwan-Ha,Noh, Da-Young,Jo, In-Hwan,Koh, Young-Hag,Choi, Won-Young,Kim, Hyoun-Ee The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.28

<P>We herein propose a novel way of producing nanofibrous gelatin–silica hybrid scaffolds through thermally induced phase-separation (TIPS) particularly using mixtures of gelatin solution and silica sol, which can mimic the physical structure, chemical composition, and eventually functions of the native bone extracellular matrix (ECM). The gelatin solutions were homogeneously hybridized with various contents of a silica sol using simple magnetic stirring, which enabled the construction of a nanofibrous structure with a uniform distribution of the silica in the gelatin nanofibers. The nanofibrous gelatin–silica hybrid scaffolds showed much better mechanical properties and <I>in vitro</I> biodegradation stability and apatite-forming ability than the nanofibrous pure gelatin scaffold, which were achieved by the presence of a stiff, bioactive silica phase in the nanofibers and the interaction between the silica hydroxyls and the amino group in the gelatin polymer. In addition, the nanofibrous gelatin–silica hybrid scaffold with a silica content of 30 wt% showed reasonably high <I>in vitro</I> biocompatibility. These findings suggest that the highly porous, nanofibrous hybrid structure mimicking the bone ECM can provide an excellent matrix for bone tissue regeneration.</P> <P>Graphic Abstract</P><P>We herein propose a novel way of producing nanofibrous gelatin–silica hybrid scaffolds through thermally induced phase-separation (TIPS) particularly using mixtures of gelatin solution and silica sol, which can mimic the physical structure, chemical composition, and eventually functions of the native bone extracellular matrix (ECM). <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2jm31290e'> </P>

Transcriptome reveals genes involving in black skin color formation of ducks

Lei Wang,Hehe Liu,Bo Hu,Jiwei Hu,Hengyong Xu,Hua He,Chunchun Han,Bo Kang,Lili Bai,Rongping Zhang,Jiwen Wang,Shengqiang Hu,Liang Li 한국유전학회 2021 Genes & Genomics Vol.43 No.2

Background Skin color is colorful for birds, which has been reported to be associated with multi-biological functions, such as crypsis, camoufage, social signaling and mate choice, but little is known about its underlying molecular mechanism. Objective Studies on the major genes afecting the black skin color of ducks. Methods For this purpose, Silver ammonia staining and RNA-seq analysis were carried out to identify the diferences in tissue morphology and gene expressions between black and yellow skin ducks. Results The silver ammonia dyes slice results showed that in the development of black duck, the content of melanin in black skin gradually increased and then decreased, and the content of melanin in yellow and black skin was signifcantly diferent. Through transcriptome, a total of 102 and 84 diferentially expressed genes (DEGs) were identifed in beak skin and web skin, respectively. These DEGs were enriched in melanin biosynthesis and play a critical role in melanogenesis pathway. Co-expression analysis showed that EDNRB2 was the only gene associated with black skin color in DEGs, which was also consistent with qRT-PCR. Conclusions The melanin synthesis pathway dominated by EDNRB2 up-regulated the amount of melanin synthesis, leading to the formation of black skin in ducks.

Application on Web Page Filtering Technology

Bo Shen,Lei Li,Ning-wei Wang 보안공학연구지원센터 2014 International Journal of Multimedia and Ubiquitous Vol.9 No.12

Web page filtering technology intends to filter out the large number of the repeated and theme-unrelated noise information and obtain useful information. Some web filtering methods cannot make full use of the layout and visual features. In view of the new mainstream “DIV+CSS” designing style of modern commercial web sites, this paper summarizes that elements laying in the same div blocks have common semantic features and proposed a DIV_FOREST model to represent the web pages. And in combination with the Vision-based Page Segmentation Algorithm, a DVPS Algorithm which considers both layout features and visual features was proposed to improve web page filtering efficiency.

Analysis on Continuous Usage Intention of Chinese Mobile Games from the Perspective of Experiential Marketing and Network Externality

Bo Lei,Jungmann Lee 한국정보기술응용학회 2020 Journal of information technology applications & m Vol.27 No.6

Mobile games have become one of the most important driving forces of the game industry. We focus on the continuous intention to use Chinese mobile games from the perspective of experiential marketing and network externalities. We integrate user experience, network externalities and flow theory into expectation confirmation model and explore the influencing factors of continuous usage intention of Chinese mobile game and propose a research model. Game experience, service experience, perceived enjoyment, social interaction, challenge, perceived number of users and perceived number of peers were employed as independent variables, while flow, perceived value and satisfaction as mediating variables and continuous intention as the dependent variable. After surveying 426 samples, the model is tested with structural equation model. The results reveal that perceived enjoyment significantly positively influences perceived value, flow, satisfaction, and continuous intention. The greater the enjoyment of the game, the greater the satisfaction of the game and the greater the willingness to use it continuously. Game experience has a significant direct effect on continuous intention, which indicates that a better game experience can retain more users. Service experience and perceive number of peers positively influence satisfaction. Another finding is that social interaction and perceived number of users positively influence perceived value and flow, which indicate that social attributes are critical roles for retaining users. Game challenge also positively influences flow. The proper level of challenge is more likely to cause users to enter the state of flow. Flow indirectly influences continuous usage intention through the satisfaction of the game, which indicates that satisfaction is driven by flow experience and further retaining users. Empirical results implied that mobile game companies need to focus on improving user experience, expectation satisfaction and extending network externalities to improve the continuous intention of using mobile game.

“親切” : 中國觀衆對韓國電視劇中“家禮”之認同感的哲學分析

雷博(Bo Lei) 서울행정학회 2006 서울행정학회 학술대회 발표논문집 Vol.- No.-

Chronic Hepatitis B Virus Infection and Risk of Pancreatic Cancer: A Meta-analysis

Li, Lei,Wu, Bo,Yang, Li-Bo,Yin, Guan-Cheng,Liu, Ji-Yong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Objectives: A number of studies have shown that chronic hepatitis B virus infection is implicated in susceptibility to pancreatic cancer. However, the results are still controversial. This meta-analysis aimed to quantitatively assess the relationship between chronic hepatitis B virus infection and incidence of pancreatic cancer of cohort and case-control studies. Methods: A literature search was performed for entries from 1990 to 2012 using PUBMED and EMBASE. Studies were included if they reported odds ratios (ORs) and corresponding 95% CIs of pancreatic cancer with respect to the infection of hepatitis B virus. Results: Eight studies met the inclusion criteria, which included five case-control studies and three cohort studies. Compared with individuals who have not infection of hepatitis B virus, the pooled OR of pancreatic cancer was 1.403 (95%CI: 1.139-1.729, P=0.001) for patients with hepatitis B virus infection. Sub-group analysis by study design showed that the summary OR was 1.43 (95%CI: 1.06-1.94, P=0.021) when pooling case-control studies and 1.31 (95%CI: 1.00-1.72, P=0.05) when pooling cohort studies. Conclusion: Findings from this meta-analysis suggest that chronic hepatitis B virus infection may increase the risk of pancreatic cancer. This relationship needs to be confirmed by further follow-up studies.

An Improved K-means Algorithm based on Mapreduce and Grid

Li Ma,Lei Gu,Bo Li,Yue Ma,Jin Wang 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

The traditional K-means clustering algorithm is difficult to initialize the number of clusters K, and the initial cluster centers are selected randomly, this makes the clustering results very unstable. Meanwhile, algorithms are susceptible to noise points. To solve the problems, the traditional K-means algorithm is improved. The improved method is divided into the same grid in space, according to the size of the data point property value and assigns it to the corresponding grid. And count the number of data points in each grid. Selecting M(M>K) grids, comprising the maximum number of data points, and calculate the central point. These M central points as input data, and then to determine the k value based on the clustering results. In the M points, find K points farthest from each other and those K center points as the initial cluster center of K-means clustering algorithm. At the same time, the maximum value in M must be included in K. If the number of data in the grid less than the threshold, then these points will be considered as noise points and be removed. In order to make the improved algorithm can adapt to handle large data. We will parallel the improved k-mean algorithm and combined with the MapReduce framework. Theoretical analysis and experimental results show that the improved algorithm compared to the traditional K-means clustering algorithm has high quality results, less iteration and has good stability. Parallelized algorithm has a very high efficiency in data processing, and has good scalability and speedup.

Simulation analysis and evaluation of decontamination effect of different abrasive jet process parameters on radioactively contaminated metal

Zhong Lin,Deng Jian,Zuo Zhe-wen,Huang Can-yu,Chen Bo,Lei Lin,Lei Ze-yong,Lei Jie-heng,Zhao Mu,Hua Yun-fei 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.11

A new method of numerical simulating prediction and decontamination effect evaluation for abrasive jet decontamination to radioactively contaminated metal is proposed. Based on the Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) coupled simulation model, the motion patterns and distribution of abrasives can be predicted, and the decontamination effect can be evaluated by image processing and recognition technology. The impact of three key parameters (impact distance, inlet pressure, abrasive mass flow rate) on the decontamination effect is revealed. Moreover, here are experiments of reliability verification to decontamination effect and numerical simulation methods that has been conducted. The results show that: 60Co and other homogeneous solid solution radioactive pollutants can be removed by abrasive jet, and the average removal rate of Co exceeds 80%. It is reliable for the proposed numerical simulation and evaluation method because of the well goodness of fit between predicted value and actual values: The predicted values and actual values of the abrasive distribution diameter are Ф57 and Ф55; the total coverage rate is 26.42% and 23.50%; the average impact velocity is 81.73 m/s and 78.00 m/s. Further analysis shows that the impact distance has a significant impact on the distribution of abrasive particles on the target surface, the coverage rate of the core area increases at first, and then decreases with the increase of the impact distance of the nozzle, which reach a maximum of 14.44% at 300 mm. It is recommended to set the impact distance around 300 mm, because at this time the core area coverage of the abrasive is the largest and the impact velocity is stable at the highest speed of 81.94 m/s. The impact of the nozzle inlet pressure on the decontamination effect mainly affects the impact kinetic energy of the abrasive and has little impact on the distribution. The greater the inlet pressure, the greater the impact kinetic energy, and the stronger the decontamination ability of the abrasive. But in return, the energy consumption is higher, too. For the decontamination of radioactively contaminated metals, it is recommended to set the inlet pressure of the nozzle at around 0.6 MPa. Because most of the Co elements can be removed under this pressure. Increasing the mass and flow of abrasives appropriately can enhance the decontamination effectiveness. The total mass of abrasives per unit decontamination area is suggested to be 50 g because the core area coverage rate of the abrasive is relatively large under this condition; and the nozzle wear extent is acceptable