• 제목/요약/키워드: Generation Alpha

검색결과 445건 처리시간 0.026초

우귀음이 Zinc에 의한 신경교세포의 고사(Apoptosis)에 미치는 영향 (Protective Effects of Ukyium(우귀음, Yougui-yin) in Zinc-induced Apoptosis of C6 Glial Cells)

  • 이영구;문병순
    • 대한한의학회지
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    • 제22권3호
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    • pp.63-73
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    • 2001
  • Objectives : The objective of the current study is to determine the protective effect of Ukyium(Yougui-yin) on the apoptosis induced by zinc. Methods : Zinc is known to generate reactive oxygen species (ROS), including superoxide anion ($O_2$) and hydrogen peroxide ($H_2O_2$), which eventually contribute to cytotoxicity in a variety of cell types. We investigated the viablity of cells, $H_2O_2$ generation, chromatin condensation and nuclear fragmentation in Hoechst dye staining and $IkB-{\alpha}$ degradation in C6 glial cells of $ZnCl_2$ between pretreatment- and not pretreatment-group with Ukyium. The former methods were researched by Time- and Dose-dependent manners. Results : We demonstrated that pretreatment with Ukyium prevented zinc-induced cell death of C6 glial cells and apoptotic characteristics including chromatin condensation and nuclear fragmentation. Ukyium also prevented $H_2O_2-induced$ cell death. We further confirmed that Ukyium decreased zinc-induced generation of $H_2O_2$ and inhibited degradation of $IkB-{\alpha}$ by zinc in C6 glial ceHs. Conclusions : These data indicated that Ukyium (Yougui-yin) prevents zinc-induced apoptotic death of C6 glial cells via inhibition of ROS generation, such as $H_2O_2$ as well as inhibition of $IkB-{\alpha}$ degradation.

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곡피(?皮)와 상목피(橡木皮) 추출물이 대식세포 RAW264.7 활성화에 미치는 영향 (Effects of Quercus dentata and Quercus acutissima Extracts on the Activations of Macrophage RAW264.7 Primed with $IFN-{\gamma}$)

  • 조진희;성낙술;이영종
    • 대한본초학회지
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    • 제21권1호
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    • pp.89-100
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    • 2006
  • Objectives : The effects of methanol extracts from the cortex of Quercus dentata Thunb. and Quercus acutissima Carruth, on the activation of macrophage were examined. Methods : Methanol extracts of Quercus dentata (QD) and Quercus acutissima (QA) were applied to cell line RAW264,7 (macrophage), and their effects were examined. Results : 1. Extracts from QD and QA had no specific influence on the cell growth. 2. Extracts from QD and QA did not activate macrophage independently, but the addition of $IFN-{\gamma}$ facilitated the generation of macrophage's nitric oxide(NO). 3. QD and QA extracts increased the manifestation of iNOS gene, when macrophage was activated by $IFN-{\gamma}$. 4. QD and QA extracts increased the manifestation of $TNF-{\alpha}$ in macrophage, which took 2 hours. 5. QD and QA extracts increased the generation of $PGE_2$ in macrophage. Conclusion : QD and QA activate macrophage in the presence of $IFN-{\gamma}$. After activation is primarily facilated by $IFN-{\gamma}$, it works on macrophage secondarily for the manifestation of iNOS gene and for the generation of $TNF-{\alpha}$.

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가설 생성 학습 후에 나타난 초등 예비교사의 뇌파 변화 (EEG Changes after Learning for Hypothesis-Generation in Elementary Pre-service Teachers)

  • 권용주;박지영;신동훈
    • 한국초등과학교육학회지:초등과학교육
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    • 제25권2호
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    • pp.159-166
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    • 2006
  • Changes in the brain activities following pre-service elementary teachers' learning hypothesis-generation were investigated using the analysis of EEG relative power and EEG coherence. In this study, the experimental group (n=16) were trained using learning methods for hypothesis-generation and the control group(n=16) were trained using learning methods for hypothesis-reception over the course of 8 weeks. EEG was measured before and following the learning process for both groups. Decreased theta ($4{\sim}7.9Hz$)/alpha 1 ($8{\sim}9.9Hz$) power and increased alpha 2 ($10{\sim}l2.9Hz$)/beta ($13{\sim}29.9Hz$)/gamma ($30{\sim}50Hz$) power were showed in the experimental group. Additionally, many changes in brian activities were observed for theta, beta and gamma coherence in the experimental group. In particular, fronto-parietal coherence increased in the experimental group. These differences in brain activities between the two groups suggest that the learning for subjects' hypothesis generation presumably leads to interesting changes in some types of brain activities in pre-service elementary teachers.

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밸브지점 균형과 교환 최적화 방법을 적용한 동적경제급전문제 (Dynamic Economic Load Dispatch Problem Applying Valve-Point Balance and Swap Optimization Method)

  • 이상운
    • 한국인터넷방송통신학회논문지
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    • 제16권1호
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    • pp.253-262
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    • 2016
  • 본 논문은 경제급전 최적화 문제에 균형-교환 방법을 제안하였다. 제안된 알고리즘은 모든 발전기를 가능한한 밸브지점으로 운영한다고 가정한다. 초기치로 최대 발전량 $P_i{\leftarrow}P_i^{max}$로 설정하고, 각 발전기의 밸브지점 $v_k$까지 발전량을 감소시켰을 때의 평균 발전단가 $c_i=\frac{F(P_i)-F(P_{iv_k})}{(P_i-P_{iv_k})}$가 최대가 되는 $_{max}c_i$ 발전기 i의 발전량을 밸브지점 발전단가 $P_{iv_k}$로 감소시켰으며, ${\Sigma}P_i-P_d$ > 0이면 $c_i=F(P_i)-F(p_i-1)$$_{max}c_i$ 발전기 발전량을 $P_i{\leftarrow}P_i-1$로 감소시켜 ${\Sigma}P_i=P_d$의 균형을 맞추었다. 다음으로, $_{min}\{_{max}(P_i-P_i^{min}),\;_{max}(P_i^{max}-P_i)\}$>${\alpha}{\geq}10$의 범위에 대해 "-10" 간격으로 감소시키는 성인걸음법으로, 10>${\alpha}{\geq}1$ 범위에 대해서는 "-1"의 아기걸음법으로, $P_i=P_i{\pm}{\alpha}$에 대한 $_{max}[F(P_i)-F(P_i-{\alpha})]$>$_{min}[F(P_j+{\alpha})-F(P_j)]$, $i{\neq}j$이면 $P_i=P_i-{\alpha}$, $P_j=P_j+{\alpha}$로 발전량을 교환하는 방법으로 최적화를 수행하였다. 다음으로 ${\alpha}=\text{0.1, 0.01, 0.001, 0.0001$에 대해 미세한 교환을 수행하였다. 동적 경제급전 문제의 시험 사례에 제안된 알고리즘을 적용한 결과 기존의 휴리스틱 알고리즘 최적화 발전비용을 크게 감소시켜 경제적인 이익을 극대화 시켰다.

어미 쥐의 $\omega$3계 및 $\omega$6계 지방산 식이가 제2세대 쥐의 뇌조직 지방산 성분에 미치는 영향 (Effect of Maternal Dietary $\omega$3 and $\omega$6 Polyunsaturated Fatty Acids on the Fatty Acid Composition of the Second Generation Rat Brain)

  • 김미경
    • Journal of Nutrition and Health
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    • 제26권6호
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    • pp.661-671
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    • 1993
  • The change in fatty acid composition in brain tissue of the second generation rats(Sprague-Dawley strain) was studied using four different fat diets(Corn oil=CO, Soybean oil=SO, Perilla oil=PO, Fish oil=FO, 10% by Wt). The experimental diets were started from pregnancy in four different groups, each consisting of 9 rats. The seound generation rats were fed the same diet as their mothers. Animals were anesthetized with ether at 0, 3, 9 & 16 weeks of age. Whole brains were dissected out, brain tissues were, then, homogenized and lipids were extracted from brain tissues. The fatty acid compositions were measured after methylation by gas-liquid chromatography at 0, 3, 9 and 16 weeks of age of offspring. The changes in the relative concentrations of polyunsaturated fatty acids(PUFA) or more specifically docosahexaenoic acid(22 : 6, $\omega$3, DHA), the major $\omega$3 fatty acid component in rat brain at different age were similar to changes in the amount of DNA in brain tissue showing the maximum value during the lactation. The changes in saturated fatty acid(SFA) content showed a contrasting patten to those of PUFA, while monounsaturated fatty acid(MUFA) increased steadily throughout the experimental period. At birth, the relative concentrations of $\omega$3 series fatty acids the relative concentrations of PUFA, MUFA and SFA converged to very similar values respectively regardless of the dietary fatty acid compositions. In brain tissue, it is of value to note that while changes in relative concentrations of linoleic acid (18 : 2, $\omega$6, LA) and arachidonic acid(20 : 4, $\omega$6, AA) showed a precursor-product-like relationship, $\alpha$-linolenic acid(18 : 3, $\omega$3, $\alpha$-LnA) and DHA showed a different pattern. Even when the $\omega$3 fatty acid content in very low in maternal diet(CO), the second generation rat brain tissues appeared to secure DHA content, suggesting an essential role of this fatty acid in the brain. The fact that a large amount of $\alpha$-LnA in the maternal diet did not have a significant effect on the second generation rat brain $\alpha$-LnA content, indicated that DHA seemed essential component for the brain development in our experimental condition. In all groups, the relative content of $\alpha$-LnA in the brain tissues remained relatively constant throughout the experimental period at the very low level. The study of the specific concentrations and essential role(s) of DHA in each parts of brain tissue is needed in more details.

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알파세대 초등학생의 학업 및 일상생활에서의 정보추구행태에 관한 연구 (An Exploratory Study of Information Seeking Behavior of Generation Alpha Elementary School Students in Academic and Everyday Life)

  • 황인범;윤정원
    • 한국비블리아학회지
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    • 제35권2호
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    • pp.25-45
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    • 2024
  • 본 연구는 알파세대에 해당하는 초등학생들의 일상생활에서의 정보추구행태를 이해하는 것을 목적으로 초등학교 4~6학년 학생들을 대상으로 설문조사를 실시하여, 일상생활에서의 정보요구, 정보요구 해결을 위해 사용하는 정보원과 선택 이유, 정보탐색 과정에서 느끼는 어려움, 획득한 정보에 대한 만족도 및 신뢰성 등을 조사하였다. 연구결과, 알파세대 초등학생들은 동영상 플랫폼을 가장 많이 활용하였으며 취미와 여가에 관한 정보요구가 가장 많았다. 이들이 정보원을 선택하는 이유로는 친근성과 편리성이 가장 주된 이유로 나타났다. 인구통계학적 특성과 미디어 리터러시 교육 여부에 따른 차이도 분석하였다. 학년, 거주지역, 형제자매 유무에 따른 뚜렷한 차이는 나타나지 않았으며, 성별에 따른 정보추구행태에 있어서만 유의미한 차이가 나타났다. 미디어 리터러시 교육을 받은 경험이 있는 학생은 그렇지 않은 학생보다 정보획득 과정에서 어려움을 더 적게 겪는 것으로 나타났다. 본 연구결과는 학교 현장에서의 알파세대를 위한 정보서비스 방안과 이들을 위한 미디어 리터러시 교육의 방향성 수립에 도움을 줄 수 있는 자료가 될 것이라 기대된다.

Lyman alpha emitting blobs at the epoch of cosmic reionization

  • Kim, Hyo Jeong;Ahn, Kyungjin
    • 천문학회보
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    • 제41권2호
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    • pp.35.2-35.2
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    • 2016
  • Lyman alpha photons emitted from the early generation galaxies are scattered through the intergalactic medium, and can be observed as Lyman alpha emitting sources. We examine the Lyman alpha line transfer mechanism by tracing the random scattering histories of Lyman alpha photons in the intergalactic medium of the early universe. The density and ionization fields are based on the 3D map by N-body + radiation transfer simulations of the epoch of reionization. The calculation is compared with analytical models, too. The emergent line profile and the size of the Lyman alpha blob are strongly tied to the density and ionization environment, likely to give constraints when high-z Lyman alpha blobs are observed.

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청혈산(淸血散)이 Redox Status 및 NF-${\kappa}$B 의존성 단백질에 미치는 영향 (Effects of Cheonghyul-San on the Generation of Redox Status and on the Expression of NF-${\kappa}$B Dependent Proteins)

  • 오정표;정지천
    • 동의생리병리학회지
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    • 제23권2호
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    • pp.464-472
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    • 2009
  • The aim of this study was to investigate the effects of Cheonghyul-san on the generation of peroxynitrite ($ONOO^-$), nitric oxide (NO) and superoxide anion radical ( ${\cdot}\;O_2^-$), and on the expression of NF-${\kappa}$B-dependent proinflammatory proteins in ob/ob mice. Mice were grouped and treated for 5 weeks as follows. Both the normal lean (C57BL/6J black mice) and control obese (ob/ob mice) groups have received the standard chow. The experimental groups were fed with a diet of chow supplemented with 7.5, 15 and 30 mg Cheonghyul-san per 1 kg of body weight for 14 days. For this study, the fluorescent probes, namely 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein-2 (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Western blot was performed using anti-IKK-${\alpha}$, anti-phospho I${\kappa}$B-${\alpha}$, anti-NF-${\kappa}$B (p50, p65), anti-COX-2, anti-iNOS, anti-VCAM-1 antibodies, respectively. Cheonghyul-san prevented $H_2O_2$-induced cell death. Cheonghyul-san inhibited the generation of $ONOO^-$, NO and ${\cdot}\;O_2^-$ in the $H_2O_2$-treated LLC-$PK_1$ cells. The generation of $ONOO^-$, NO and ${\cdot}\;O_2^-$ were inhibited in the Cheonghyul-san-administered ob/ob mice groups. The GSH/GSSG ratio was decreased in the ob/ob mice, whereas the ratio was improved in the Cheonghyul-san-administered groups. Cheonghyul-san inhibited the protein expression levels of phospho-I${\kappa}$B-${\alpha}$, IKK-${\alpha}$, NF-${\kappa}$B (p50, p65), COX-2, iNOS and VCAM-1 genes. These results suggest that Cheonghyul-san is an effective scavenger of $ONOO^-$, ${\cdot}\;O_2^-$ and NO, and has an inhibitory effect on the expression of NF-${\kappa}$B-dependent inflammatory genes in ob/ob mice. Therefore, Cheonghyul-san might be used as a potential therapeutic drug against the diabetes- and obesity-related proinflammatory diseases.

An Arithmetic System over Finite Fields

  • Park, Chun-Myoung
    • Journal of information and communication convergence engineering
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    • 제9권4호
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    • pp.435-440
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    • 2011
  • This paper propose the method of constructing the highly efficiency adder and multiplier systems over finite fields. The addition arithmetic operation over finite field is simple comparatively because that addition arithmetic operation is analyzed by each digit modP summation independently. But in case of multiplication arithmetic operation, we generate maximum k=2m-2 degree of ${\alpha}^k$ terms, therefore we decrease k into m-1 degree using irreducible primitive polynomial. We propose two method of control signal generation for the purpose of performing above decrease process. One method is the combinational logic expression and the other method is universal signal generation. The proposed method of constructing the highly adder/multiplier systems is as following. First of all, we obtain algorithms for addition and multiplication arithmetic operation based on the mathematical properties over finite fields, next we construct basic cell of A-cell and M-cell using T-gate and modP cyclic gate. Finally we construct adder module and multiplier module over finite fields after synthesizing ${\alpha}^k$ generation module and control signal CSt generation module with A-cell and M-cell. Next, we constructing the arithmetic operation unit over finite fields. Then, we propose the future research and prospects.

비균질 다공성 매질의 효율적 해석 방법 (Effective Method for Analysis of Heterogeneous Porous Media)

  • 박창근
    • 한국수자원학회논문집
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    • 제31권4호
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    • pp.459-467
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    • 1998
  • 유사매질개념에 의하여 비균질 다공성 매질을 설명할 수 있는 기존의 방법은 미시 밀러 상사(Mis), 거시 밀러 상사(MaS)와 웨릭 상사(WS)로 나눌 수 있고, 그들간의 관계는 MiS ⊂ MaS⊂ WS(⊂: subset)임을 알 수 있었다. 본 연구에서 제안한 방법은 WS에서 축적변수 $\alpha$=w 로 가정하고 함수량을 포화도 대신 유효포화도로 축적한 것이다. 이 방법은 검사해석의 관점에서 일반성이 결여되지 않고, 축적변수 $\alpha$만으로 비균질 매질을 설명할 수 있다. 즉 =1($\alpha$의 평균값)인 매질은 비균질 매질에 상응하는 등가매질을 의미하고, $\alpha$의 표준편차는 다공성 매질의 비균질 정도를 설명한다. $\alpha$>1인 매질의 특수계수는 등가매질의 투수계수보다 크며 또한 유효함수량은 $\alpha$>1인 매질에서 크게 나타난다. 이와같은 $\alpha$의 성질을 이용하여 가상적인 여직 1차원 비균질 다공성 매질을 난수 발생기법으로 생성하였다.

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