Cloning and Expression of the Xylanase Gene From Bacillus Coagulans and the M Gene of Newcastle Disease Virus in Lactococcus Lactis

Lactococcus lactis is being developed as a vaccine delivery system as it bears no threat to animal and human health. It has been used for centuries in the fermentation of foods and is generally recognised as safe. However, a safety factor pertaining to the type of selectable marker present on the vector system poses to be of concern. Chances of the transfer of antibiotic resistance genes, usually employed by vectors as selectable markers, into the natural environment become a possible risk. Therefore, there is a need for the development of ideal vectors without such selectable markers (Dertzbaugh, 1998). The activity of the xylanase gene of Bacillus coagulans ST -6 can be detected on Remazol Brilliant Blue-Xylan (RBB-Xylan) as a clear halo zone against a dark blue background. This characteristic allows xylanase to be used as a selectable chromogenic marker on any vector system. On the other hand, the matrix or membrane (M) protein of Newcastle disease virus (NDV) strain AF 2240 can be useful as an antigen to generate antibody response towards NDV infection in chickens.Both, the xylanase gene (0.8 kb) of B. coagulans ST-6 and the M gene (1.1 kb) of NDV strain AF 2240 were cloned in lactococcal expression vector pMG36e and transformed into Escherichia coli XLI-blue MRF'. The recombinant plasmids, pMG36e-X and pMG36e-X-M were sub-cloned into L. lactis MG 1363 via electroporation. The insertion and orientation of the xylanase gene was confmned using restriction enzyme analysis and PCR amplification. Xylanase activity and expression on RBB-Xylan agar plates further confmned its presence in the recombinant plasmid pMG36e-X. In addition, the enzyme activity was also quantitatively showed using the Somogyi-Nelson assay. The sequence of the M gene obtained in clone pMG36e-X-M from L. lactis MG 1363 was found to be 99% homologous to the established sequence (Jemain, 1999). Expression of the fusion M protein was studied at the transcriptional leve1. RT -PCR was used to detect the transcription of the gene using RNA of L. lactis MG1363 containing the recombinant plasmid pMG36e-X-M as template. The size of the RT-PCR product correlated with the size of the cloned M gene (1.1 kb). In addition, the RT-PCR product was sequenced to confirm the presence of the M gene. Based on the results obtained, recombinant plasmids pMG36e-X and pMG36e-X-M were successfully constructed and introduced into E. coli XLI-blue-MRF' and L. lactis MG1363. The recombinant DNA pMG36e-X is capable of expressing the xylanase gene and can be further developed as a chromogenic selection marker for a new and improved food-grade shuttle vector for E. coli and L. lactis. On the other hand, expression of the fusion M gene was detected at transcriptional level in recombinant clone pMG36e-X-M

On the Mass-Period Distributions and Correlations of Extrasolar Planets

In addition to fitting the data of 233 extra-solar planets with power laws, we construct a correlated mass-period distribution function of extrasolar planets, as the first time in this field. The algorithm to generate a pair of positively correlated beta-distributed random variables is introduced and used for the construction of correlated distribution functions. We investigate the mass-period correlations of extrasolar planets both in the linear and logarithm spaces, determine the confidence intervals of the correlation coefficients, and confirm that there is a positive mass-period correlation for the extrasolar planets. In addition to the paucity of massive close-in planets, which makes the main contribution on this correlation, there are other fine structures for the data in the mass-period plane.Comment: to be published in AJ, tentatively in December 200

The Impact of Experience in Service Virtualization on Travel Intention - The Case of Forbidden City Tour

The advent of Internet and home shopping economy in the recent years has reduced the intention of people to leave home for sightseeing. This has significantly impacted the growth of physical tourism industry. This paper utilizes the virtual tour of Forbidden City to conduct a sequence of experiments in tourism experience. Before using the system, Theory of Planned Behavior and Involvement are employed to measure the intention of traveling. After then, two constructs, emotion and system, are adopted to explore how the experiential value of virtual tourism impacts the intention of travelling. The experience of tour virtualization allows customers to create unforgettable feelings in the virtual world. It can affect not only the customer’s experiential value of virtual tourism, but also intention of traveling in the future

Increased ATP generation in the host cell is required for efficient vaccinia virus production

To search for cellular genes up-regulated by vaccinia virus (VV) infection, differential display-reverse transcription-polymerase chain reaction (ddRT-PCR) assays were used to examine the expression of mRNAs from mock-infected and VV-infected HeLa cells. Two mitochondrial genes for proteins that are part of the electron transport chain that generates ATP, ND4 and CO II, were up-regulated after VV infection. Up-regulation of ND4 level by VV infection was confirmed by Western blotting analysis. Up-regulation of ND4 was reduced by the MAPK inhibitor, apigenin, which has been demonstrated elsewhere to inhibit VV replication. The induction of ND4 expression occurred after viral DNA replication since ara C, an inhibitor of poxviral DNA replication, could block this induction. ATP production was increased in the host cells after VV infection. Moreover, 4.5 μM oligomycin, an inhibitor of ATP production, reduced the ATP level 13 hr after virus infection to that of mock-infected cells and inhibited viral protein expression and virus production, suggesting that increased ATP production is required for efficient VV production. Our results further suggest that induction of ND4 expression is through a Bcl-2 independent pathway

From Structural Assurances to Trusting Beliefs: Validating Persuasion Principles in the Context of Online Shopping

The topic of shopping attitude has received long lasing attention in the context of e-commerce. Previous studies have elucidated the different facets of online shopping attitude and have overemphasized a prevalent assertion on the relationship between web design artifacts and consumers’ psychological responses. However, the imitability of web design in practice makes no differentiation among a glut of shopping websites and probably leads to revenue declination due to the fact that the instability of attitude frequently leads to attitudinal ambivalence. Hence, understanding how to strengthen consumers’ attitudes toward online shopping should be fruitful for remedying attitude inconsistency in e-commerce. The current study extended related research by examining the simultaneous effects of trusting beliefs on consumers’ attitudes toward online shopping. We adopted the concept of structural assurance and the principles of persuasion as the theoretical underpinnings. The proposed model is expected to contribute to relevant literature by offering theoretical contributions and managerial implications that can help both researchers and online retailers to understand more clearly how consumers develop their attitudes toward shopping online

Profit Maximization by Forming Federations of Geo-Distributed MEC Platforms

This paper has been presented at: Seventh International Workshop on Cloud Technologies and Energy Efficiency in Mobile Communication Networks (CLEEN 2019). How cloudy and green will mobile network and services be? 15 April 2019 - Marrakech, MoroccoIn press / En prensaMulti-access edge computing (MEC) as an emerging technology which provides cloud service in the edge of multi-radio access networks aims to reduce the service latency experienced by end devices. When individual MEC systems do not have adequate resource capacity to fulfill service requests, forming MEC federations for resource sharing could provide economic incentive to MEC operators. To this end, we need to maximize social welfare in each federation, which involves efficient federation structure generations, federation profit maximization by resource provisioning configuration, and fair profit distribution among participants. We model the problem as a coalition game with difference from prior work in the assumption of latency and locality constraints and also in the consideration of various service policies/demand preferences. Simulation results show that the proposed approach always increases profits. If local requests are served with local resource with priority, federation improves profits without sacrificing request acceptance rates.This work was partially supported by the Ministry of Science and Technology, Taiwan, under grant numbers 106-2221-E-009-004 and by the H2020 collaborative Europe/Taiwan research project 5G-CORAL (grant number 761586)

An Investigation of Factors Affecting Financial Performance of Taiwanese International Tourist Hotels

This study adopts moving average regression and panel data regression to explore the factors affecting the financial performance of international tourist hotels in Taiwan. First, we use the unit root test to examine the data in moving average regression and in panel data regression and then use the Hausman test to examine whether the fixed-effects or random-effects model is suitable for panel data regression. Second, we employ the Lagrangian multiplier (LM) test to confirm that panel data regression is better. The findings show that domestic visitors, occupancy rate, operation year, and joining a chain system are the four key factors affecting financial performance