• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.208-212
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• 2012

In previous studies, ovarian follicle in rat has been used a higher radiation dose than that for cancer radiotherapy in clinical practice. The aim of this study was to evaluate the effect of radiation dose used for cancer radiotherapy on ovarian follicle atresia in rat. Mice of 4-week-old female were whole body irradiated with 2 cGy or 2 Gy (Mevatron 67, Siemens, Germany) and sacrificed by cervical dislocation. Ovaries were collected at 24 hours after irradiation to observe the degree of follicular atresia. Ovaries were fixed in neutral formaldehyde solution for 24 hours and embedded with paraffin. Cutted in $5{\mu}m$ thickness with microtome and stained with hematoxylin and eosin (H&E) and TUNEL immunohistochemical stain, and examined histologically under a light microscope. All data were presented as mean ${\pm}SD$, calculating the ratio of normal or atretic follicles to total ovarian follicles. Statistical analysis was performed by the Mann Whitney test using the SPSS ver 19.0. Ratio of atretic to total follicles of 2 Gy group was significantly higher than control or 2 cGy groups (p<0.05). Ratio of normal to total follicles of 2 Gy group was significantly lower than control group in preantral follicle (64.0 vs. 87.7, p=0.027). Ratio of normal to total follicles of 2 cGy group was significantly increased more than control or 2 Gy groups in antral follicle, and there were no significant difference between control and 2 Gy groups (p=0.522). Radiation dose of 2 Gy for cancer radiotherapy have a significant effect on ovarian follicle atresia in rat.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.155-169
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• 2014

With the rapid advances in technologies, organizations are more likely to depend on information systems in their decision-making processes. Business Intelligence (BI) systems, in particular, have become a mainstay in dealing with complex problems in an organization, partly because a variety of advanced computational methods from statistics, machine learning, and artificial intelligence can be applied to solve business problems such as demand forecasting. In addition to the ability to analyze past and present trends, these predictive analytics capabilities provide huge value to an organization's ability to respond to change in markets, business risks, and customer trends. While the performance effects of BI system use in organization settings have been studied, it has been little discussed on the use of predictive analytics technologies embedded in BI systems for forecasting tasks. Thus, this study aims to find important factors that can help to take advantage of the benefits of advanced technologies of a BI system. More generally, a BI system can be viewed as an advisor, defined as the one that formulates judgments or recommends alternatives and communicates these to the person in the role of the judge, and the information generated by the BI system as advice that a decision maker (judge) can follow. Thus, we refer to the findings from the advice-giving and advice-taking literature, focusing on the role of explanations of the system in users' advice taking. It has been shown that advice discounting could occur when an advisor's reasoning or evidence justifying the advisor's decision is not available. However, the majority of current BI systems merely provide a number, which may influence decision makers in accepting the advice and inferring the quality of advice. We in this study explore the following key factors that can influence users' advice taking within the setting of a BI system: explanations on how the box-office grosses are predicted, types of advisor, i.e., system (data mining technique) or human-based business advice mechanisms such as prediction markets (aggregated human advice) and human advisors (individual human expert advice), users' evaluations of the provided advice, and individual differences in decision-makers. Each subject performs the following four tasks, by going through a series of display screens on the computer. First, given the information of the given movie such as director and genre, the subjects are asked to predict the opening weekend box office of the movie. Second, in light of the information generated by an advisor, the subjects are asked to adjust their original predictions, if they desire to do so. Third, they are asked to evaluate the value of the given information (e.g., perceived usefulness, trust, satisfaction). Lastly, a short survey is conducted to identify individual differences that may affect advice-taking. The results from the experiment show that subjects are more likely to follow system-generated advice than human advice when the advice is provided with an explanation. When the subjects as system users think the information provided by the system is useful, they are also more likely to take the advice. In addition, individual differences affect advice-taking. The subjects with more expertise on advisors or that tend to agree with others adjust their predictions, following the advice. On the other hand, the subjects with more knowledge on movies are less affected by the advice and their final decisions are close to their original predictions. The advances in predictive analytics of a BI system demonstrate a great potential to support increasingly complex business decisions. This study shows how the designs of a BI system can play a role in influencing users' acceptance of the system-generated advice, and the findings provide valuable insights on how to leverage the advanced predictive analytics of the BI system in an organization's forecasting practices.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.83-91
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• 2018

Advances in bacterial and fungal genome mining uncover a plethora of cryptic secondary metabolite biosynthetic gene clusters. Guided by the genome information, targeted transcriptional derepression could be employed to determine the product of a cryptic gene cluster and to explore its biological role. Monascus spp. are food grade filamentous fungi popular in eastern Asia and several genome data belong to them are now available. We achieved transcription activation of a cryptic fungal polyketide synthase-nonribosomal peptide synthase gene Mpfus1 in Monascus purpureus ${\Delta}MpPKS5$ by inserting Aspergillus gpdA promoter at the upstream of Mpfus1 through double crossover gene replacement. The gene cluster with Mpfus1 show a high similarity to those for the biosynthesis of conjugated polyene derivatives with 2-pyrrolidone ring and the mycotoxin fusarin is the representative member of this group. The ${\Delta}MpPKS5$ is incapable of producing azaphilone pigment, providing an excellent background to identify chromogenic and UV-absorbing compounds. Activation of Mpfus1 resulted in a yellow hue on mycelia and its methanol extract exhibit a maximum absorption at 365 nm. HPLC analysis of the organic extracts indicated the presence of a variety of yellow compounds in the extract. This implies that the product of MpFus1 is metabolically or chemically unstable. LC-MS analysis guided us to predict the MpFus1 product and to propose that the Mpfus1-containing gene cluster encode the biosynthesis of a desmethyl analogue of fusarin. This study showcases the genome mining in Monascus and the possibility to unveil new biological activities embedded in it.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.21-35
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• 2018

Since the introduction of MP3 players, CD recordings have gradually been vanishing, and the music consuming environment of music users is shifting to mobile devices. The introduction of smart devices has increased the utilization of music through music playback, mass storage, and search functions that are integrated into smartphones and tablets. At the time of initial MP3 player supply, the bitrate of the compressed music contents generally was 128 Kbps. However, as increasing of the demand for high quality music, sound quality of 384 Kbps appeared. Recently, music content of FLAC (Free License Audio Codec) format using lossless compression method is becoming popular. The download service of many music sites in Korea has classified by unlimited download with technical protection and limited download without technical protection. Digital Rights Management (DRM) technology is used as a technical protection measure for unlimited download, but it can only be used with authenticated devices that have DRM installed. Even if music purchased by the user, it cannot be used by other devices. On the contrary, in the case of music that is limited in quantity but not technically protected, there is no way to enforce anyone who distributes it, and in the case of high quality music such as FLAC, the loss is greater. In this paper, the author proposes an audio watermarking technology for copyright protection of high quality stereo music. Two kinds of information, "Copyright" and "Copy_free", are generated by using the turbo code. The two watermarks are composed of 9 bytes (72 bits). If turbo code is applied for error correction, the amount of information to be inserted as 222 bits increases. The 222-bit watermark was expanded to 1024 bits to be robust against additional errors and finally used as a watermark to insert into stereo music. Turbo code is a way to recover raw data if the damaged amount is less than 15% even if part of the code is damaged due to attack of watermarked content. It can be extended to 1024 bits or it can find 222 bits from some damaged contents by increasing the probability, the watermark itself has made it more resistant to attack. The proposed algorithm uses quantization in DCT so that watermark can be detected efficiently and SNR can be improved when stereo music is converted into mono. As a result, on average SNR exceeded 40dB, resulting in sound quality improvements of over 10dB over traditional quantization methods. This is a very significant result because it means relatively 10 times improvement in sound quality. In addition, the sample length required for extracting the watermark can be extracted sufficiently if the length is shorter than 1 second, and the watermark can be completely extracted from music samples of less than one second in all of the MP3 compression having a bit rate of 128 Kbps. The conventional quantization method can extract the watermark with a length of only 1/10 compared to the case where the sampling of the 10-second length largely fails to extract the watermark. In this study, since the length of the watermark embedded into music is 72 bits, it provides sufficient capacity to embed necessary information for music. It is enough bits to identify the music distributed all over the world. 272 can identify $4*10^{21}$, so it can be used as an identifier and it can be used for copyright protection of high quality music service. The proposed algorithm can be used not only for high quality audio but also for development of watermarking algorithm in multimedia such as UHD (Ultra High Definition) TV and high-resolution image. In addition, with the development of digital devices, users are demanding high quality music in the music industry, and artificial intelligence assistant is coming along with high quality music and streaming service. The results of this study can be used to protect the rights of copyright holders in these industries.

• Tuberculosis and Respiratory Diseases
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• v.49 no.1
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• pp.49-59
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• 2000

Backgrounds : Recent cytogenetic studies indicated that long of the long arm of chromosome 5 is a frequent event in small cell lung canær (SCLC), suggesting the presence of a tumor suppressor gene in its place. To map the precise tumor-suppressor loci on the chromosome arm for further positional cloning efforts, we tested 15 primary SCLCs. Methods : The DNAs extracted from paraffin-embedded tissue blocks with primary tumor and corresponding control tissue were investigated. Nineteen polymorphic microsatellite markers located in the long arm of chromosome 5 were used in the microsatellite analysis. Results : We found that ten (66.7%) of 15 tumors exhibited LOH in at least one of tested microsatellite markers. Two (13%) of 10 tumors exhibiting LOH lost a larger area in chromosome 5q. LOH was observed in five common deleted regions at 5q. Among those areas, LOH between 5q34-qter and 5q35.2-35.3 was most frequent (75%). LOH was also observed in more than 50% of the tumors at four other regions, between 5q14-15 and 5q23-31, 5q31.1, 5q31.3-33.3, and 5q34-35. Three of 15 tumors exhibited shifted bands in at least one of the tested microsatellite markers. Shifted bands occurred in 2.5% (7 of 285) of the loci tested. Conclusion : Our data demonstrated that at least five tumor-suppressor loci exist in the long arm of chromosome 5 and that they may play an important role in small cell lung cancer tumorigenesis.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.93-102
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• 2016

Purpose: The aim of this study was to evaluate the fit accuracy of two zirconia and titanium abutments in internal hexagonal implants. Materials and methods: One titanium abutment and two zirconia abutments were tested in internal hexagonal implants (TSV, Zimmer). Prefabricated zirconia abutments (ZirAce, Acucera) and customized zirconia abutments milled by the Zirkonzahn system (Zirkonzahn Max, Zirkonzahn) were selected and prefabricated titanium abutments (Hex-Lock, Zimmer) were used as a control. Eight abutments per group were connected to implants with 30 Ncm torque. The marginal gaps at abutment-implant interface, the internal gaps at internal hex, vertical and horizontal gaps between screws and screw seats in abutments were measured after sectioning the embedded specimens using a scanning electron microscope. Data analysis included one-way analysis of variance and the Scheffe test (n=16, ${\alpha}=0.05$). Results: The mean marginal gap of customized zirconia abutment was higher than those of two prefabricated zirconia and titanium abutments. The internal gaps at internal hex showed no significant differences between customized and prefabricated abutments and were higher than those of prefabricated titanium abutments. The mean vertical and horizontal gaps at screw in prefabricated zirconia abutment were higher than those of prefabricated titanium abutment. In the case of customized zirconia abutment, the mean horizontal gap at screw was higher than those of both the prefabricated zirconia and the titanium abutment but the mean vertical gap was not even measureable. The screw seats were clearly formed but did not match with abutment screws in prefabricated zirconia abutments. They were not, however, precisely formed in the case of customized zirconia abutments. Conclusion: Within the limitations of this study, the prefabricated titanium abutments showed better fit than the zirconia abutments, regardless of customized or prefabricated. Also, the customized zirconia abutments showed significantly higher marginal gaps and the fit was less accurate between screws and screw seats than the prefabricated abutments, titanium and zirconia.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.520-527
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• 2008

Purpose: This study was conducted to evaluate the shear bond strength of composite resin to dentin when etched with laser instead of phosphoric acid. Material and methods: Recently extracted forty molars, completely free of dental caries, were embedded into acrylic resin. After exposing dentin with diamond saw, teeth surface were polished with a series of SiC paper. The teeth were divided into four groups composed of 10 specimens each; 1) no surface treated group as a control 2) acid-etched with 35%-phosphoric acid 3) Er:YAG laser treated 4) Er,Cr:YSGG laser treated. A dentin bonding agent (Adapter Single Bond2, 3M/ESPE) was applied to the specimens and then transparent plastic tubes (3 mm of height and diameter) were placed on each dentin. The composite resin was inserted into the tubes and cured. All the specimens were stored in distilled water at $37^{\circ}C$ for 24 hours and the shear bond strength was measured using a universal testing machine (Z020, Zwick, Germany). The data of tensile bond strength were statistically analyzed by one-way ANOVA and Duncan's test at ${\alpha}$= 0.05. Results: The bond strengths of Er:YAG laser-treated group was $3.98{\pm}0.88$ MPa and Er,Cr:YSGG laser-treated group showed $3.70{\pm}1.55$ MPa. There were no significant differences between two laser groups. The control group showed the lowest bond strength, $1.52{\pm}0.42$ MPa and the highest shear bond strength was presented in acid-etched group, $7.10{\pm}1.86$ MPa (P < .05). Conclusion: Laser-etched group exhibited significantly higer bond strength than that of control group, while still weaker than that of the phosphoric acid-etched group.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.535-543
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• 2008

Purpose: The objective of this study was to compare the bonding characteristics of a new self-adhesive resin cement to dentin, which does not require bonding and conditioning procedure of the tooth surface, and conventional resin cement. The effect of phosphoric acid etching prior to application of self-adhesive resin cement on the shear bond strength was also evaluated. Material and methods: Fortyfive non-carious human adult molars extracted within 6 months were embedded in chemically cured acrylic resin. The teeth were ground with a series of SiC-papers ending with 800 grit until the flat dentin surfaces of the teeth were exposed. The teeth were randomly divided into 3 experimental groups. In group 1, self-adhesive resin cement, RelyX Unicem (3M ESPE, Seefeld, Germany) was bonded without any conditioning of teeth. In group 2, RelyX Unicem was bonded to teeth after phosphoric acid etching. For group 3, Syntac Primer (Ivoclar Vivadent AG, Schaan, Liechtenstein) was applied to the teeth before Syntac adhesive (Ivoclar Vivadent AG, Schaan, Liechtenstein) and Helibond (Ivoclar Vivadent AG, Schaan, Liechtenstein) followed by conventional resin cement, Variolink II (Ivoclar Vivadent AG, Schaan, Liechtenstein). To make a shear bond strength test model, a plastic tuble (3 mm diameter, 3 mm height) was applied to the dentin surfaces at a right angle and filled it with respective resin cement, and light-polymerized for 40 seconds. All the specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before test. Universal Testing Machine (Z020, Zwick, Ulm, Germany) at a cross head speed of 1 mm/min was used to evaluate the shear bond strength. The failure sites were inspected under a magnifier and Scanning Electron Microscope. The data was analyzed with One way ANOVA and Scheffe test at ${\alpha}$= 0.05. Results: (1) The shear bond strengths to dentin of RelyX Unicem was not significantly different from those of Variolink II/Syntac. (2) Phosphoric acid etching lowered the shear bond strength of RelyX Unicem significantly. (3) Most of RelyX Unicem and Variolink II showed mixed fractures, while all the specimens of RelyX Unicem with phosphoric acid etching demonstrated adhesive failure between dentin and resin cement. Conclusion: Shear bond strength to dentin of self-adhesive resin cement is not significantly different from conventional resin cement, and phosphoric acid etching decrease the shear bond strength to dentin of self-adhesive resin cement.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.1-42
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• 2009

In a knowledge-based society, a firm's intellectual capital represents the wealth of ideas and ability to innovate, which are indispensable elements for the future growth. Therefore, the intellectual capital is evidently recognized as the most valuable asset in the organization. Considered as intangible asset, intellectual capital is the basis based on which firms can foster their sustainable competitive advantage. One of the essential components of the intellectual capital is a social capital, indicating the firm's individual members' ability to build a firm's social networks. As such, social capital is a powerful concept necessary for understanding the emergence, growth, and functioning of network linkages. The more social capital a firm is equipped with, the more successfully it can establish new social networks. By providing a shared context for social interactions, social capital facilitates the creation of new linkages in the organizational setting. This concept of "person-environment fit" has long been prevalent in the management literature. The fit is grounded in the interaction theory of behavior. The interaction perspective has a fairly long theoretical tradition, beginning with proposition that behavior is a function of the person and environment. This view asserts that neither personal characteristics nor the situation alone adequately explains the variance in behavioral and attitudinal variables. Instead, the interaction of personal and situational variables accounts for the greatest variance. Accordingly, the person-environment fit is defined as the degree of congruence or match between personal and situational variables in producing significant selected outcomes. In addition, information systems acceptance factors enable organizations to build large electronic communities with huge knowledge resources. For example, the Intranet helps to build knowledge-based communities, which in turn increases employee communication and collaboration. It is vital since through active communication and collaborative efforts can employees build common basis for shared understandings that evolve into stronger relationships embedded with trust. To this aim, the electronic communication network allows the formation of social network to be more viable to rapid mobilization and assimilation of knowledge assets in the organizations. The purpose of this study is to investigate: (1) the impact of person-environment fit(person-job fit, person-person fit, person-group fit, person-organization fit) on social capital(network ties, trust, norm, shared language); (2) the impact of information systems acceptance factors(availability, perceived usefulness, perceived ease of use) on social capital; (3) the impact of social capital on personal performance(work performance, work satisfaction); and (4) the mediating role of social capital between person-environment fit and personal performance. In general, social capital is defined as the aggregated actual or collective potential resources which lead to the possession of a durable network. The concept of social capital was originally developed by sociologists for their analysis in social context. Recently, it has become an increasingly popular jargon used in the management literature in describing organizational phenomena outside the realm of transaction costs. Since both environmental factors and information systems acceptance factors affect the network of employee's relationships, this study proposes that these two factors have significant influence on the social capital of employees. The person-environment fit basically refers to the alignment between characteristics of people and their environments, thereby resulting in positive outcomes for both individuals and organizations. In addition, the information systems acceptance factors have rather direct influences on the social network of employees. Based on such theoretical framework, namely person-environment fit and social capital theory, we develop our research model and hypotheses. The results of data analysis, based on 458 employee cases are as follow: Firstly, both person-environment fit(person-job fit, person-person fit, person-group fit, person-organization fit) and information systems acceptance factors(availability perceived usefulness, perceived ease of use) significantly influence social capital(network ties, norm, shared language). In addition, person-environment fit is a stronger factor influencing social capital than information systems acceptance factors. Secondly, social capital is a significant factor in both work satisfaction and work performance. Finally, social capital partly plays a mediating role between person-environment fit and personal performance. Our findings suggest that it is vital for firms to understand the importance of environmental factors affecting social capital of employees and accordingly identify the importance of information systems acceptance factors in building formal and informal relationships of employees. Firms also need to reflect their recognition of the importance of social capital's mediating role in boosting personal performance. Some limitations arisen in the course of the research and suggestions for future research directions are also discussed.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.43-72
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• 2009

Recently, user-created content (UCC) have emerged as popular medium of on-line participation among users. The Internet environment has been constantly evolving, attracting active participation and information sharing among common users. This tendency is a significant deviation from the earlier Internet use as an one-way information channel through which users passively received information or contents from contents providers. Thanks to UCCs online users can now more freely generate and exchange contents; therefore, identifying the critical factors that affect content-generating activities has increasingly become an important issue. This paper proposes a set of critical factors for stimulating contents generation and sharing activities by Internet users. These factors were derived from the theories of folklores such as tales and songs. Based on some shared traits of folklores and UCC content, we found four critical elements which should be heeded in constructing UCC contents, which are: context of culture, context of situation, skill of generator, and response of audience. In addition, we selected three major UCC websites: a specialized contents portal, a general internet portal, and an official contents service site, They have different use environments, user interfaces, and service policies, To identify critical factors for generating, sharing and transferring UCC, we traced user activities, interactions and flows of content in the three UCC websites. Moreover, we conducted extensive interviews with users and operators as well as policy makers in each site. Based on qualitative and quantitative analyses of the data, this research identifies nine critical factors that facilitate contents generation and sharing activities among users. In the context of culture, we suggest voluntary community norms, proactive use of copyrights, strong user relationships, and a fair monetary reward system as critical elements in facilitating the process of contents generation and sharing activities. Norms which were established by users themselves regulate user behavior and influence content format. Strong relationships of users stimulate content generation activities by enhancing collaborative content generation. Particularly, users generate contents through collaboration with others, based on their enhanced relationship and specialized skills. They send and receive contents by leaving messages on website or blogs, using instant messenger or SMS. It is an interesting and important phenomenon, because the quality of contents can be constantly improved and revised, depending on the specialized abilities of those engaged in a particular content. In this process, the reward system is an essential driving factor. Yet, monetary reward should be considered only after some fair criterion is established. In terms of the context of the situation, the quality of contents uploading system was proposed to have strong influence on the content generating activities. Among other influential factors on contents generation activities are generators' specialized skills and involvement of the users were proposed. In addition, the audience response, especially effective development of shared interests as well as feedback, was suggested to have significant influence on contents generation activities. Content generators usually reflect the shared interest of others. Shared interest is a distinct characteristic of UCC and observed in all the three websites, in which common interest is formed by the "threads" embedded with content. Through such threads of information and contents users discuss and share ideas while continuously extending and updating shared contents in the process. Evidently, UCC is a new paradigm representing the next generation of the Internet. In order to fully utilize this innovative paradigm, we need to understand how users take advantage of this medium in generating contents, and what affects their content generation activities. Based on these findings, UCC service providers should design their websites as common playground where users freely interact and share their common interests. As such this paper makes an important first step to gaining better understand about this new communication paradigm created by UCC.