Charakterisierung stromaler Zellinien fu@r die Kultivierung humaner ha@mopoetischer Zellen

MeiΒner, Petra 1995 국내박사

How computer-mediated communication affects ELL students' writing processes and writing performance

Lin, Show-Mei The University of Oklahoma 2009 해외공개박사

The overarching purpose of this study was to examine the impact of CMC technology on ELL students' writing processes and writing performance through interacting, communicating, constructing knowledge, and collaborating with peers from different cultural and linguistic backgrounds. This study intended to reform teaching methods for ELL writing from a teacher-centered approach to a student-centered approach. In addition to the discussion forum (NICENET), used to address students' individual learning needs, this study incorporated CMC technology tools that supported tutorial writing lessons (Essay Punch, Paragraph punch), interactive multimedia grammar practices (Grammar Fitness), online bilingual dictionaries, and other online writing links (websites/labs) to improve students' writing skills. Offering unlimited time (class time) and place (classroom), CMC technology incorporated both individualized learning processes and social interaction learning to facilitate ELL writing processes and writing outcomes. Mixed methods were utilized in this study: quantitative methods, including writing difficulties/needs questionnaires, quantity of participation, pre-test quality (score) of writing samples, post-test quality (score) of writing samples, and qualitative research methods, including reflection journals and interviews. The results of the questionnaire data showed that most ELLs perceived their highest writing difficulties (needs) in linguistic/cognitive deficiencies (M=3.91; SD=.53), next highest in psychological/emotional deficiency (M=2.78; SD=1.20) and the third in sociocultural aspects of writing difficulties(M=2.50;SD=1.00). After CMC technology intervention designed to address students' self-perception of writing difficulties (needs), sociocultural (percentage gains = -21%) aspects of writing difficulties were reduced the most, cognitive/linguistic (percentage gains= -18%) aspects of writing difficulties were reduced the second, and psychological/emotional (percentage gains=-17%) aspects of writing were reduced the least. In terms of students' writing performance, there was a trend towards an improved level of performance. Students showed improvement in their quantity of writing, organization, thesis statements, ideas, and use of multiple perspectives. However, a majority of students did not show much improvement in grammar usage (run-on sentences and articles) and word choice. Comparing two groups, the CMC technology group outperformed the control group on self-perceptions of sociocutlrual and, psychological/emotional aspects of writing, and in percent gains between pretest and posttest of writing performance. During the writing processes, there were advantages and disadvantages about using CMC technology for ELL writing instruction. A majority of students had a high level of positive perceptions of CMC technology and participation, had a high level of discussion, reduced their writing anxiety, became more confident, and felt that they made progress in multiple perspectives, critical thinking, identifying writing errors, spelling, grammar, implementing writing processes, and adapting to American writing conventions. Participants described advantages most on cognitive/linguistic aspects of writing. On the other hand, the cognitive/linguistic disadvantages included conflicting feedback, longer time for revising, and harder revision. The technological difficulties included lack of creativity and flexibility in the writing software. The sociocultural difficulties were spending much more time on building an online learning community for emotional support and knowledge sharing/building. In the beginning of the study, students were reluctant to share with their ELL peers about their English writing because they were afraid that their peers might look down upon their writing abilities or they did not have confidence in their ELL peers' writing ability to be able to offer constructive or meaningful feedback and suggestions. However, gradually students began to establish a learning community where they not only helped each other to write but also offered emotional support to their peers by showing empathy and suggesting problem-solving strategies in their writing. Students became actively in using writing to express ideas, negotiate differences, support other people's emotional needs, and solve problems. Metacognitive strategies and higher-order cognitive strategies were facilitated through online discussion and interaction.

THE EPISCOPALIAN MISSIONARIES IN CHINA, 1835-1900

LIN, MEI-MEI University of Texas at Austin 1994 해외박사

The maintenance ability and Ca2+ availability of skeletal muscle are enhanced by sildenafil

Huang, Mei 가톨릭대학교 대학원 2017 국내박사

The supply of private higher education in Taiwan: Policy options and issues

Song, Mei-Mei Columbia University Teachers College 2001 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

This study explores the possibility of encouraging the expansion of private colleges and universities in Taiwan to relieve the excess demand for higher education. Related issues are also examined: quality of students after expansion, quality assurance of higher education institutions, tuition policy, fundraising policy, and the role of the Ministry of Education (MOE) in tertiary education. As in many Confucian societies, the Taiwanese people highly appreciate the value of a college diploma. Higher education has thus been in great demand, which becomes particularly difficult for policymakers to ignore after the country's unprecedented political and economic liberalization in the mid-1980s. Since then, Taiwan has experienced a phenomenal growth in 4-year colleges and universities. Some problems such as insufficient public funding, however, soon followed the expansion. The possibility of expanding private higher education subsequently emerged. The private sector, nevertheless, has its own problems: insufficient revenues; lack of academic autonomy to realize unique educational philosophy; inability to freely recruit students; rigid controls of the MOE, etc. These problems have put private colleges and universities in a position of inferior status in relation to their public counterparts. The purposes of this study are the following: (1) Explore the feasibility of encouraging private tertiary education expansion in response to the high social demand. (2) Examine the impact of the government's regulated mechanism for tertiary education on 4-year colleges and universities, particularly for the private sector. (3) Search for ways of enhancing the quality of higher education, especially for the private sector. (4) Analyze the effect of the current financing policies on tertiary education, particularly the private sector. (5) Make policy recommendations based on the analysis of the study. The methodology of qualitative analysis has been adopted in this study. In-depth interviews with 58 elite college administrators (presidents and deans of academic affairs, general affairs, and student affairs) in Taiwan were conducted to acquire insights regarding policies and practices in the country's higher education system. Findings and policy implications in respect of the development of Taiwanese higher education are presented. Policy recommendations are made for the MOE and college administrators, respectively.

Application of Biological algal control technology : Comparative study on algal grazers and its application to Artificial Floating Island

Mei ? Yan Jin 경희대학교 2013 국내석사

In this study, physical and biological technologies using herbivorous zooplankton and artificial floating island were developed and its efficiency was estimated algal biomass controling. Aquatic macrophytes and media are widely used in eutrophic water. In addition, biological control of algal biomass is the method based on classical top-down control of algal biomass using herbivorous zooplankton. The key species in biological control is cladoceran genus, Daphnia, since it is major grazer on highvariety of phytoplankton species. Thus, its intensive grazing can suppress algal growth efficiently in water body. For efficient controlling of algal biomass in the water body, the equipment devised in this study was combined with media (bio-stone), aquatic macrophytes (Oenanthe javanica) and herbivorous cladoceran (Daphnia similoides) in artificial floating island (AFI). Removal efficiency in Chl. a concentration controlling of AFI was tested using different combinations of each device: B.D-mixture bio-stone and Daphnia similoides, O.B-mixture Oenanthe javanica and bio-stone, B.O.D-mixture bio-stone, Oenanthe javanica and Daphnia similoides, and the out-put water quality improvement was compared with C-control (no device was applied). We analyzed removal efficiency of Chl. a concentration and nutrient concentrations in the artificially eutrophic water in the laboratory experimental facility. The results showed average removal rates of Chlorophyll a, TN and TP for different four groups: 69%, 16.61%, -0.61%; 68%, 14.11%, 10.52%; 78%, 6.69%, 25.09%; 35%, -3.47%, -25.18%, respectively. The results have suggested that the mixture of media, plants and zooplankton is the most efficient combination for Chlorophyll a control, while the mixture of macrophytes and bio-stone have better efficiency nutrient control.

Performance analysis of BCH-LDPC concatenated code for NAND flash memory : 낸드플래시메모리를 위한 BCH-LDPC 연접부호의 성능분석

Mei, Yaqing 경북대학교 대학원 2015 국내석사

최근 낸드플래시메모리의 용량은 다중레벨셀기술과 반도체칩기술 등에 의해 크게 향상되었다. 하지만 낸드플래시의 입력 BER 상황은 오히려 열화되었다. 따라서 EG-LDPC 부호가 낸드플래시의 오류정정부호로서 고려되고 있다. EG-LDPC 부호는 부호복잡도가 낮고 높은 부호율에서도 오류마루현상이 발생하지 않는다. 하지만 이 부호는 폭포영역에서 상대적으로 나쁜 성능을 보인다. 그러므로 낸드플래시 사용가능기간의 중반이후부터는 신뢰도가 급격히 감소한다. 따라서 낸드플래시메모리의 사용기간을 늘리기 위하여 본 논문에서는 높은 부호율을 가지는 SeIRA, 비균일랜덤, 그리고 EG-LDPC 부호의 성능을 비교 및 분석하였다. 그리고 낸드플래시가 요구하는 BER 성능에 도달하기 위하여 SeIRA LDPC 부호에 BCH부호를 연접하는 방식을 제안하였다. 모의실험 결과, 단일 SeIRA LDPC 부호와 SeIRA LDPC 부호를 사용한 연접부호는 폭포영역에 들어가기 위하여 EG-LDPC 부호에 비하여 낮은 SNR을 요구하였다. 하지만 단일 SeIRA LDPC 부호에서는 BER이 10-10 일 때 오류마루현상이 발견되었으며, 오류마루현상은 연접부호를 사용하더라도 낮아지거나 제거되지 않았다. 따라서 메모리 사용 초반부에서는 SeIRA LDPC 부호가 EG-LDPC 부호에 비해 낮은 신뢰도를 가지지만 중반부 이후부터는 EG-LDPC 부호 보다 SeIRA LDPC 부호를 사용하는 것이 더 유리할 것으로 사료된다. 또한 SeIRA LDPC 부호의 복호시 패리티검사행렬의 특별한 사이클에 의하여 발생된 오류 수의 주기적인 패턴 때문에 연접부호를 사용하더라도 BER이 향상되지 않음을 확인하였다. 그러므로 SeIRA-BCH 연접부호를 낸드플래시메모리 환경에 적용하기 위해서는 패리티검사행렬 속의 특별한 사이클을 제거하거나 이 사이클로 인하여 발생된 주기적 패턴에서 오류의 수를 최소화 시킬 수 있는 방안이 필요할 것으로 사료된다. 그러면 BCH-SeIRA 연접부호가 EG-LDPC 부호보다 낸드플래시 메모리에 더 적합할 것으로 기대된다.

Immunosuppressive Actions of N-Acyl dopamines and Antioxidative Actions of N-Acyl 5-hydroxytryptamines

Jin, Mei-Chen 忠南大學校 大學院 2014 국내박사

Endocannabinoids는 신경전달기능 등 다양한 생리활성효과를 나타내는 것으로 알려져 있다. 본 연구에서는 concanavalin A (Con A)에 의해 활성화된 생쥐의 비장세포에서 N-acyl dopamines이 나타내는 항면역 효과를 조사하고, 이어서 glutamate에 의해 활성화된 HT22세포에서 N-acyl 5-hydroxytryptamines (5-HTs)의 항산화 보호효과를 평가하고자 하였다. 우선 concanavalin A에 의해 활성화된 생쥐의 비장세포에서 N-acyl dopamines의 항면역 효과를 관찰한 결과 N-arachidonoyl dopamine (NADA), N-oleoyl dopamine (NODA) 과 N-palmitoyl dopamine (NPDA)은 Con A에 의한 세포증식 (IC50, 1.84 μM, 2.45 μM 과 8.54 μM) 과 interferon-γ (IFN-γ), tumor necrosis factor-α 및 interleukin-2의 생성 (IFN- γ 생성억제 IC50, 0.58 μM, 0.77 μM 과 4.33 μM)을 현저하게 저해하였고 NADA과 NODA의 효과는 NPDA보다 더욱 우수한 것으로 관찰되었다. 다음 연구에서 NADA과 NPDA의 항면역 효과는 cannabinoid receptor (CB)1 길항제인 SR141716과 transient receptor potential vanilloid1 (TRPV1) 길항제인 5’-Iodoresiniferatoxin에 의해 부분적으로 저해되엇으나, CB2 길항제 AM630에 의해서는 저해되지 않았고, NODA의 항면역 작용은 5’-Iodoresiniferatoxin에 의해서만 부분적으로 저해되었다. 별도로 NADA과 NODA은 TRPV1 작용제인 12(S)-hydroxyeicosatetraenoic acid의 생성을 높여주었다. 따라서 이러한 Con A에 의한 세포증식에 대한 N-acyl dopamines의 억제효과는 부분적인 CB1와 TRPV1에 대한 작용에 기인하는 것으로 파악된다. 이어서 HT22세포에서 glutamate에 의해 유도된 산화적 스트레스에 대한 N-acyl 5-HTs의 보호효과를 관찰하였다. Palmitoyl, stearoyl, arachidonoyl, oleoyl 및 docosahexaenoyl 사슬을 갖고 있는 N-acyl 5-HTs는 glutamate에 의한 HT22 세포의 세포사를 현저하게 보호하였고 (EC50, 0.23 µM), 아울러 글루타치온의 감소 및 ROS 생성도 뚜렷하게 보호하였다. 또한 N-palmitoyl 5-HT는 항 산화 효소인 glutamyl cysteine ligase catalytic subunit (GCLC), NADP(H)-quinone oxidoreductase 1 (NQO1)와 heme oxygenase-1 (HO-1), 의 발현을 증가시켰으며 아울러 항산화 효소 발현에 핵심적인 Nrf2의 핵 이동을 촉진시켰다. 이와 관련된 기전연구에서 N-palmitoyl 5-HT에 의한 Nrf2의 활성화와 GCLC의 발현은 p-38 MAPK (SB203580), PI3K (LY294002), PDK1 (OSU-03012) 및 Akt (MK-2206) 억제제에 의해서 감소되는 것으로 관찰되었다. 따라서 HT22세포에서 glutamate에 의한 산화적 스트레스에 대한 N-acyl 5-HT의 보호효과는 p38 MAPK와 PI3K/PDK1/Akt 경로들의 활성화를 통해 Nrf2의 핵 이동을 촉진시킴으로써 항 산화효소의 발현을 증가시키는 결과로 해석된다. 또한 이러한 항산화 능력의 보강은 MEK/ERK 경로의 활성화를 저해함으로서 세포사를 저해하는 것으로 평가되었다. 이와 같이 N-acyl 5-HT는 p38 MAPK와 PI3K/PDK1/Akt/ARE 신호조절경로를 통해 항 산화기능을 발휘하며 아울러 glutamate에 의한 MEK/ERK1/2 경로의 활성화를 저해하는 것으로 관찰됨으로 이에 대한 구체적인 연구를 토대로 뇌 질환을 방지하는 우수한 항 산화 보호제의 개발이 기대된다. Some N-acyl dopamines have been reported to show anti-inflammatory and immunomodulatory activities. In this respect, the immunosuppressive effect of N-acyl dopamines on splenocytes of BALB/c mice were examined. First, when the effect of each endocannabinoid or its derivative on concanavalin A (Con A)-induced proliferation of splenocytesexamined was , N-arachidonoyl dopamine (NADA), N-oleoyl dopamine (NODA) and N-palmitoyl dopamine (NPDA) potently suppressed Con A-mediated splenocyte proliferation with IC50 value of 1.84 μM, 2.45 μM and 8.54 μM, respectively, indicating that NADA and NODA were more immunosuppressive than NPDA. In related study, the immunosuppressive effect of NADA or NPDA was antagonized partially by CB1 antagonist, SR141716 and transient receptor potential vanilloid 1 (TRPV1) antagonist, 5’-Iodoresiniferatoxin (5’-IRTX), but not CB2 antagonist, AM630. Meanwhile, the effect of NODA was suppressed partially by 5’-IRTX, but not other antagonists. In further study to support the immunosuppressive activity of N-acyl dopamines, the effect of N-acyl dopamaines on the release of cytokines was investigated. Noteworthy, NADA (IC50, 0.53 μM), NODA (IC50, 0.78 μM) and NPDA (IC50, 2.45 μM) inhibited the secretion of interferon-γ from Con A-stimulated splenocytes concentration-dependently. A similar suppression of the release of tumor necrosis factor (TNF)-α and interleukin-2 was also expressed by N-acyl dopamines. Additionally, the suppressive effect of NADA or NPDA on cytokine release was antagonized partly by SR141716 or 5’-IRTX, and that of NODA was antagonized partly by 5’-IRTX. Separately, NADA and NODA enhanced the level of 12(S)-hydroxyeicosatetraenoic acid an endogenous TRPV1 agonist. These findings suggest that N-acyl dopamines may express immuno-modulatory action through pathways involving CB1 and TRPV1 receptors in splenocytes. Separately, some endocannabinoids have been known to express anti-inflammatory and antioxidant actions independent of cannabinoid receptors. In this respect, the N-acyl 5-hydroxytryptamines (5-HTs) might prevent against glutamate-induced oxidative cytotoxicity in HT22 cells were investigated, and attempted to elucidate the mechanism for their neuroprotective action. N-acyl 5-HTs with palmitoyl, stearoyl, arachidonoyl or docosahexaenoyl chain expressed a remarkable protective effect on glutamate-induced cytotoxicity. Additionally, glutamate-induced oxidative stress, represented by the increase of ROS and the decrease of glutathione (GSH) level, was prevented markedly by N-acyl 5-HTs at submicromolar levels. Further, N-palmitoyl 5-HT, the most cytoprotective, enhanced antioxidant defense by up-regulating the expression of antioxidant enzymes such as heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic (GCLC) and NADP(H)-quinone oxidoreductase 1 (NQO1). Consistent with this, N-palmitoyl 5-HT stimulated nuclear translocation of Nrf2, and the Nrf2 tranfer was significantly suppressed by inhibitors of p-38 MAPK and phosphatidylinositol 3-kinase (PI3K). Collectively, it is suggested that N-acyl 5-HTs may attenuate glutamate-induced oxidative cytotoxicity via the activation of p-38 MAPK and PI3K/PDK1/Akt-dependent Nrf2 signaling, and suppressive of MEK/ERK1/2 pathway activation in HT22 cells. Taken together, it is proposed that N-acyl endocannabiloids such as N-acyl dopamines and N-acyl 5-hydroxytryptamines may be a new type of potent anti-inflammatory / antioxidant lipid agents.

(The) turnover intention of post-90s new employees in Chinese state-owned commercial banks : the mediating role of commitment and the moderating role of gender

Mei, Ke 중앙대학교 대학원 2020 국내석사

Organization capital in the Korean market

Liu, Mei Graduate School, Yonsei University 2019 국내석사

I test whether the positive relationship between organization capital and stock return documented in the US stock market holds in the Korean stock market, and whether the difference is caused by human capital risk. The results show that organization capital does not appear to affect stock returns in Korea. Although a recursive stock proxy based on total SG&A generates a significant difference in excess return between high and low portfolios, the difference does not seem to be attributable to organization capital and human capital risk. The hypothesis that the difference may be caused by higher downside risk from sticky SG&A costs is also ruled out. The results provide evidence against a human capital risk explanation for the effect of organization capital on stock returns.