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        23.
        2018.11 구독 인증기관·개인회원 무료
        Microenvironments surrounded with various extracellular matrix (ECM) components can decide specifically the fate of spermatogonial stem cells (SSCs) and integrin heterodimers recognizing directly ECM proteins play an important role in transporting ECM-derived signals into cytoplasm, resulting in inducing a variety of biological functions such as cell attachment, self-renewal and differentiation. However, to date, studies on type of integrin heterodimers expressed functionally on the undifferentiated SSCs derived from mouse with hybrid strain remain unclear. Therefore, we tried to investigate systematically what kind of integrin heterodimers are expressed transcriptionally, translationally and functionally in the SSCs derived from testis of hybrid (B6CBAF1) mouse. For these, magnetic activated cell sorting (MACS) using Thy1 antibody was used for isolating SSCs from testis, and real-time PCR or fluorescence immunoassay was conducted for measuring transcriptional or translational level of integrin α and β subunits in the isolated SSCs. Subsequently, antibody inhibition assay was conducted for confirming functionality of presumed integrin heterodimers. As the results, transcriptional levels of genes encoding total 25 integrin subunits were quantified, 7 integrin α (α4, α6, α7, α9, αV, αL and αE) and 2 integrin β (β1 and β5) subunit genes showed significantly increased transcriptional up-regulation, compared to the other integrin subunit genes. In contrast, integrin α3, α5, α10 and α11, and integrin β2, β3, β4 and β7 were weakly transcribed. When translational levels of the integrin α subunits showing high transcription level (α4, α6, α7, α9, αV, αL and αE) were measured, significantly strong translational up-regulation of integrin α6, α7, α9, αV and αL subunit genes were detected, whereas integrin α4 and αE subunit genes were weakly. In case of integrin β subunit, β1 evaluated more expression than β5. Based on these results, we speculated that the undifferentiated SSCs derived from B6CBAF1 mouse might express integrin α4β 1, α6β1, α7β1, α9β1, αVβ1 or αVβ5 on plasma membrane. Subsequently, the hybrid strain SSCs showed significantly increased adhesion to fibronectin, laminin, tenascine-C and vitronectin and functional blocking of integrin α4β1, α6β1, α9β1, and αVβ1 or αVβ5 in SSCs significantly inhibited attachment to fibronectin, laminin, tenascin-C and vitronectin, respectively. Accordingly, we could identify that the hybrid (B6CBAF1) mouse-derived SSCs had integrin α4β1, α6β1, α9β1, αVβ1 or αVβ5 on plasma membrane. Moreover, this information will greatly contribute to constructing non-cellular niche supporting self-renewal of SSCs in the future.
        25.
        2018.10 구독 인증기관·개인회원 무료
        Toll and IMD pathways play an important role in producing antimicrobial peptides (AMPs) through NF-κB in insects. The functions of IκB kinase (IKK) complex regulating the NF-κB signaling cascade have not yet been investigated in Tenebrio model. Here, we identified TmIKK-β (or TmIrd5) which contains 2,112 bp encoding 703 amino acid residues. Domain analysis shows that TmIKK-β contains one Serine/Threonine protein kinases catalytic domain. Developmental expression patterns indicate that TmIKK- β gene was highly expressed in early pupal (P1) and adult (A5) stages. Tissue specific profiles show that TmIKK-β was highly expressed in the integuments in last instar larvae, and fat body and hemocytes in 5 day-old adults. TmIKK-β1 transcripts were strongly induced at 3 and 12 h-post injection of E. coli, and 3 h-post injection of S. aureus or C. albicans in hemocytes. In gut, TmIKK-β transcripts were slightly induced by E. coli (at 6, 9 and 24 h) and C. albicans (at 24 h), while it was not induced by S. aureus challenge. Moreover, it was highly induced at 6 h-post injection of E. coli and then it was gradually decreased in the fat body. To understand the immunological role of TmIKK-β, gene specific RNAi and mortality assay was performed. Depletion of TmIKK-β mRNA leads to increase microbial susceptibility of larvae against E. coli, S. aureus and C. albicans. In addition, induction patterns of fourteen AMP genes in response to microbial challenge was tissue specifically investigated in TmIKK-β–silenced T. molitor larvae. The results suggest that expression of ten AMP genes out of fourteen genes were drastically decreased by TmIKK-β RNAi in fat body, suggesting that TmIKK-β plays an important role in antimicrobial innate immune responses.
        26.
        2018.10 구독 인증기관·개인회원 무료
        It has been well known that IKK-β, -ε and –γ play a pivotal role in IMD pathway. In this study, TmIKK-ε was identified and their functions in countering pathogenic infections were investigated. We identified TmIKK-ε gene which including 2,196 bp nucleotides (encoding 731 amino acid residues). Domain analysis of TmIKK-ε indicates that there is one Serine/Threonine protein kinases catalytic domain. TmIKK-ε gene was highly expressed in 2 day-old pupal stage and the expression was gradually decreased until 1 day-old adults. Then the expression was slightly increased until 4 day-old adult stage. Tissue specific expression of TmIKK-ε mRNA was high in the gut, integuments and hemocytes in last instar larvae, and fat body, Malpighian tubules and testis in 5-daysold adult. In hemocytes, TmIKK-ε was drastically induced by E. coli injection after 3 h and by S. aureus at 3 and 12 h-post injection. In gut, expression level of TmIKK-ε was high at 6 h-post injection of microbial injection. Expression of TmIKK-ε in fat body was drastically induced by E. coli at 3 and 24 h-post injection while it was not significantly induced by S. aureus and C. albicans. To understand the immunological role of TmIKK-ε, gene specific RNAi and mortality assay were performed. TmIKK-ε RNAi caused increased larval mortality against E. coli, not S. aureus and C. albicans. Finally, to investigate the induction patterns of Tenebrio fourteen AMP genes in response TmIKK-ε RNAi, three microorganisms were treated into TmIKK-ε-silenced T. molitor larvae. Nine out of fourteen AMP genes were not induced by microbial challenge in TmIKK-β dsRNA-injected group. Taken together, our results indicate that TmIKK-ε may regulates nine antimicrobial peptide genes in response to microbial challenge in T. molitor fat body.
        27.
        2018.10 구독 인증기관·개인회원 무료
        IKK-γ is an essential protein to form IKK complex which regulate NF-κB. We identified TmIKK-γ (or TmKenny) gene which has 1,521 bp of nucleotides encoding 506 amino acid residues. Domain analysis of TmIKK-γ shows that there are one NF-κB essential modulator (NEMO) domain and a leucine zipper domain. Expression of TmIKK-γ gene was gradually increased from egg to 2-day-old pupal stage, dramatically decreased until 7 day-old pupal stage, and then it was gradually increased. TmIKK-γ transcripts were highly expressed in fat body and hemocytes in late instar larvae and integuments, fat body and Malpighian tubules in 5 day-old adult. TmIKK-γ was drastically induced by E. coli after 3 h challenges and by S. aureus at 3 and 12 h-post injection in hemocytes. TmIKK-γ was not induced by C. albicans although it was significantly induced by E. coli (at 3, 6 and 24 h) and S. aureus (at 9 h) in gut. In fat body, expression of TmIKK-γ was drastically induced by E. coli at 3 and 24 h-post injection while it was not significantly induced by S. aureus and C. albicans. To understand the immunological role of TmIKK-γ, gene specific RNAi and mortality assay was performed. larval mortality against microbial challenge was dramatically increased by TmIKK-γ RNAi. Furthermore, we investigate the tissue specific induction patterns of fourteen AMP genes in response TmIKK-γ dsRNA-treatment. In fat body, ten AMP genes out of fourteen was not significantly induced by microbial challenge in TmIKK-γ dsRNA-treated group. Based on these results, TmIKK-γ might play an important role in antimicrobial innate immune responses in Tenebrio molitor.
        28.
        2018.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 기존에 재배된 바 없었던 암대극을 새로운 관상식물로 개발하고자, 절화 특성 평가를 실시하였다. 2017년 3월과 4월, 제주도에 자생하고 있는 암대극을 채취한 후, 수분흡수, 절화수명, 노화 과정 등 절화수명 특성을 평가하였다. 또한 sucrose 농도, 절화길이, pH 농도, 저장온도에 따른 절화 특성을 조사하였다. 본 실험은 국립수목원 유용식물증식센터의 Phyto-garden system(12h photoperiod, 25℃, 70% RH)과 실온(23℃, 44% RH)에서 수행하였고 2~3일 간격으로 수분흡수량, 생체중, 절화수명을 측정하였다. 실험 환경에 따른 연구에서 실온(14.4일) 보다 phyto-garden system(42.4일)의 절화 수명이 약 3배 더 길었고, 절화길이에 따른 연구에서는 절화수명이 20cm, 15.2일, 40cm, 17.4일로 나타났다. Sucrose 농도에 따른 연구에서는 처리에 따른 절화수명 증진 효과는 없었고, pH에 따른 연구의 절화수명은 pH 5, 15.6일, pH 6, 13.4일, pH 7, 13.1일, 증류수, 14.8일이었다. 저장온도에 따른 실험에서, 절화수명은 4℃, 83일, 10℃, 41.2일, 15℃, 35.5 일, 20℃, 17.4일, 실온, 14.4일이었는데, 온도가 감소할수록 절화수명이 길어짐을 알 수 있었다. 결론적으로, 암대극은 비교적 광도와 습도가 높은 환경과 절화길이가 길고 저장온도가 낮을수록 수명이 오래 유지되는 것을 알 수 있었다.
        4,000원
        29.
        2018.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 국내 유통 중인 농산물 9품목(n = 578)에 대한 납과 카드뮴 함량을 조사하고 이들의 섭취로 인한 위해성을 평가하고자 하였다. 납과 카드뮴의 함량은 마이크로웨이브 분해 후 ICP-MS로 분석하였다. 조사대상 농산물의 납 평균 함량은 각각 보리 0.014 mg/kg, 완두콩 0.010 mg/kg, 강낭콩 0.008 mg/kg, 녹두 0.006 mg/kg, 파인애플 0.008 mg/kg, 살구 0.016 mg/kg, 매실 0.015 mg/kg, 자두 0.021 mg/kg, 대추 0.019 mg/kg이었고, 카드뮴 평균함량은 보리 0.017 mg/kg, 완두콩 0.004 mg/kg, 강낭콩 0.007 mg/kg, 녹두 0.005 mg/kg, 파인애플 0.001 mg/kg, 살구 0.002 mg/kg, 매실 0.002 mg/kg, 자두 0.002 mg/kg, 대추 0.003 mg/kg이었다. 모든 시료의 납, 카드뮴 함량은 EU, CODEX 및 국내 기준보다 낮은 수준이었다. 조사 대상 농산물에 대한 납, 카드뮴의 인체노출량을 산출한 결과, 납은 잠정주간섭취허용량(PTWI, 25 μg/kg b.w./week)의 0.067%, 카드뮴은 월간잠정섭취허용량(PTMI, 25 μg/kg b.w./month)의 0.28%이었다. 이상의 결과는 조사 대상 농산물의 납, 카드뮴 오염도와 이들의 섭취에 의한 위해성이 모두 낮은 수준이라는 것을 보여준다.
        4,000원
        30.
        2018.07 구독 인증기관·개인회원 무료
        This study tries to focus on the psychological influence by social media on user and tries to find a relationship between psychological influence and consumption patterns. Therefore, we contend that social media are platforms of interaction in that they can generate social empowerment—users feeling that they have an impact on others which gives them high self-worth (Sara Hanson, 2017) and temporarily rise self-worth can lead low self-control. Khan and Dhar (2006) find that a prior virtuous act can momentarily increase one’s self-concept, which leads to more self-indulgence in unrelated decisions. In this paper, we also investigated the two types of social media users by their presentation focus (self vs. other). In social media, there are two types of users: player & watcher. Players are users who have many followers, post lots of information about themselves and need love and attention from other users. Thus, a player which is called self-presentation focus (Wilcox, 2013) is defined as a user who focuses on information they are presenting to people in social media. In contrast, watchers are users who don’t post information on social media as actively as players but love to observe and like or dislike other users’ posts. Thus, a watcher which is called other-presentation focus (Wilcox, 2013) is defined as a user who focuses on information people present to them in social media and this is called other-presentation focus. In general, players could feel more social empowerment because posting information can be one of the activities involving interacting with other users. However, we contend that watchers will feel rather more social empowerment because having an impact, or having the feeling of social empowerment, involves the perception that one’s actions are beneficial to others, which is giving a like or comment to other user in social media (Grant and Campbell 2007). This research will have several theoretical and managerial implications. First, this study will show the influence of social media on users’ behavior and mentality, and which are related to self-control and social-empowerment. Second, this study will discover which type of social media user can be affected effectively by firms’ social media efforts.
        33.
        2017.07 구독 인증기관·개인회원 무료
        The advanced information technology leads to network age, making existing competitive advantages such as differentiation and cost leadership powerless in B2B context. The competitiveness of individual firm plays a significant role in enhancing the competitive advantage of a business network that a firm belongs to. The competitiveness of a business network depends on value co-creation, the interaction among firms in a network. Value co-creation has desirable and risky aspects. The increases in profits, brand reputation, and time and cost efficiency, client and supplier learning, etc. are positive aspects. But role conflicts, role ambiguity, and tension, etc. are negative outcomes. How can the industrial firm succeed in value co-creation with its partners in B2B context? The study focuses on the firm’s strategic marketing orientations as an antecedent of value co-creation. Strategic marketing orientations as the values and beliefs of the firm affect the collaboration with other firms during value co-creation. Previous literature assumes that a firm pursues one single strategic orientation. However, the study assumes that an industrial firm has entrepreneurial orientation, market orientation, long-term orientation, and relationship orientation. The study mostly focused on the relationships among those strategic marketing orientations. Based on these inter-relationships, the study proposed a set of value co-creation activity criteria such as information seeking, information sharing, personal interaction, responsible behavior, feedback, helping, advocacy, tolerance. Value co-creation has been evaluated by relationship performance such as trust and commitment. The study examined the relationships between strategic marketing orientations and value co-creation. Data was collected from 159 Korean manufacturers in B2B context and analyzed through structural equation modeling. The study provides evidence that entrepreneurial orientation affects market orientation positively and market orientation has positive effects on long-term orientation and relationship orientation, and long-term orientation and relationship orientation influence value co-creation directly. Value co-creation has a positive effect on relationship performance. The results of the study provide valuable implications to the mangers of industrial firms in B2B context. To succeed the value co-creation, the firm first has to look at the difference between strategic marketing orientations that the value co-creation partners pursue. In terms of selecting value co-creation partner, industrial firm with long-term orientation and relationship orientation will be more effective. Six activities of interactions during value co-creation play an important role in enhancing trust and commitment. The study contributes to the value co-creation literature by identifying strategic marketing orientations as independent variable influencing the value co-creation in B2B context. The study has several limitations that call for future research.
        34.
        2017.05 구독 인증기관·개인회원 무료
        Generally, fate of spematogonial stem cells (SSCs) can be determined specifically by microenvironments enclosed with various extracellular matrix (ECM) components and integrins recognizing directly ECM proteins play an pivotal role in transporting ECM-derived signals into cytoplasm, resulting in inducing a variety of biological functions such as cell attachment, self-renewal and differentiation. However, to date, studies on type of integrins expressed on the undifferentiated SSCs remain unclear. Therefore, we tried to investigate systematically what kind of integrin subunits are expressed transcriptionally or translationally in the SSCs derived from testis of hybrid B6CBAF1 mouse. For these, isolation of SSCs from testis were conducted by magnetic activated cell sorting (MACS) using Thy1 antibody. Subsequently, transcriptional and translational level of integrin α and β subunits in the isolated SSCs were measured by real-time PCR and fluorescene immunoassay, respectively. As the results, transcriptional levels of genes encoding total 25 integrin subunits were quantified, and integrin α4, α6, α7, α9, αV, αL and αE and integrin β1, β5 showed higher expression levels than other subunits. By contrast, integrin α3, α5, α 10 and α11 and integrin β2, β3, β4, β7 were weakly transcribed. When translational levels of the integrin α subunits showing high transcription level (α4, α6, α7, α9, αV αL, and αE) were measured, integrin α6, α7, α9, αV and αL were higher than integrin α4 and αE. In case of integrin β subunit, β1 evaluated more expression than β5. From these results, we speculate that the undifferentiated SSCs derived from hybrid B6CBAF1 mouse may express integrin α4β1, α6β1, α7β1, α9β1, αVβ1 and/or αVβ5 on plasma membrane. Moreover, this information will greatly contribute to constructing non-cellular niche supporting self-renewal of SSCs in the future.
        38.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        약용식물을 플러그 트레이를 이용하여 공정육묘를 한 연구결과는 거의 없는 실정이다. 세 종류 약용식 물 묘의 생산을 위한 기준을 마련하기 위해 플러그셀 크기가 플러그묘의 생장에 미치는 영향을 구명하기 위하여 본 연구를 수행하였다. 상업용 상토가 들어있는 128, 200, 288구 플러그셀 트레이에 종자를 파종하였다. 세 종류 약용식물은 플러그 셀 크기가 커질수록 생육이 우수하였다. 하나의 플러그 트레이에서 얻어진 총 바이오 매스는 차조기와 산두근은 288구에서 가장 높았고, 참당귀는 200구에서 가장 높았다. 총 엽록소와 안토시아닌 함량을 제외한 차조기의 지상부와 지하부 생장은 128구에서 가장 우수하였다. 하지만 최대근장, 엽장, 엽폭, 엽 면적, 절간장, 뿌리 생체중, 근군형성은 200구와 288구에서 유의한 차이가 없었다. 산두근은 최대근장, 경경, 엽폭, 엽면적, 지상부 생체중, 근군형성을 제외한 모든 생장에서 처리간에 유의한 차이가 없었다. 그러나 최대 근장, 경경, 엽폭, 엽면적, 지상부 생체중, 근군형성은 128구에서 가장 우수하였다. 엽록소 함량을 제외한 참당 귀의 지상부와 지하부의 모든 생장이 128구에서 우수하였다. 경제적인 부분과 총 바이오매스를 고려했을 때 차조기와 산두근은 288구에서 육묘하는 것이 좋고, 참당귀는 200구에서 육묘하는 것을 권장한다.
        4,000원
        39.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Spermatogonial stem cells (SSCs) developed into sperms through spermatogenesis have been utilized as a useful tool in the field of regenerative medicine and infertility. However, a small number of highly qualified SSCs are resided in the seminiferous tubule of testis, resulted in developing effective in-vitro culture system of SSCs for solving simultaneously quantitative and qualitative problems. Presently, SSCs can be enriched on testicular stromal cells (TSCs), but there are no systematic researches about TSC culture. Therefore, we tried to optimize culture condition of TSCs derived from mouse with different strains. For these, proliferation and viability were measured and compared by culturing ICR outbred or DBA/2 inbred mouse-derived TSCs at 35 or 37℃. In case of ICR strain, primary TSCs cultured at 37℃ showed significantly higher proliferation and viability than those at 35℃ and significant increase of proliferation and viability in sub-passaged TSCs was detected in the 35℃ culture condition. Moreover, sub-passage of primary TSCs at 35℃ induced no significant effects on proliferation and viability. In contrast, in case of DBA/2 strain, significantly improved proliferation were detected in the primary TSCs cultured at 35℃, which showed no significant difference in the viability, compared to those at 37℃. Furthermore, sub-passaged TSCs cultured at 37℃ showed no significant differences in proliferation and viability, compared to those at 35℃. However, with significant decrease of proliferation induced by sub-passage of primary TSCs at 35℃, no significant effects on proliferation and viability were resulted from sub-passage of primary TSCs at 37℃. From these results, culture temperature of primary TSCs derived from outbred and inbred strain of mouse could be separately optimized in primary culture and subculture.
        4,000원
        40.
        2012.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This study investigated whether or not there is any difference in the extent to which incidental vocabulary learning takes place according to the presence of background knowledge. Along with background knowledge, three other variables such as reading comprehension ability, reading strategies, and knowledge of words were examined to determine how each variable contributes to incidental vocabulary learning. The data from two groups of 60 second grade students in a Korean middle school was analyzed in this research, and the followings were measured: the use of reading strategies, reading comprehension ability, knowledge of passage sight vocabulary, background knowledge on a text, and knowledge of target words. The findings revealed that the participants inferred the meaning of unknown words better when they had more background knowledge. Each of the four variables was a significant predictor of their incidental vocabulary learning and played a facilitative role in the lexical inferencing process. The results are discussed in terms of the conditions for efficient incidental vocabulary learning through reading.
        6,300원
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