• 한국전기전자재료학회논문지
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• 제21권2호
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• pp.126-130
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• 2008

In this study, in order to develop low loss multilayer piezoelectric actuator, PZN-PZT ceramics were fabricated using $Li_2CO_3,\;Bi_2O_3$, CuO and ZnO as sintering aids, their structural, piezoelectric and dielectric characteristics were investigated according to the amount of ZnO addition, At the sintering temperature of $870^{\circ}C$, the density, electromechanical coupling factor(kp), mechanical quality factor(Qm), dielectric constant(${\epsilon}_r$) and piezoelectric constant($d_{33}$) of 0.4 wt% ZnO added specimen (sintered at $870^{\circ}C$) showed the optimum value of $7.812g/cm^3$, 0.535, 916, 1399, 335 pC/N respectively. Taking into consideration above piezoelectric properties of the specimen sintered at low temperature, it was concluded that PZN-PZT ceramics using 0.4 wt% ZnO as additive showed the optimum characteristics as the composition ceramics for low loss multilayer piezoelectric actuator application.

• 한국환경생태학회지
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• 제22권2호
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• pp.83-97
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• 2008

북한산국립공원의 현존식생 및 녹지자연도와 외래식물 분포실태를 2007년에 조사하였다. 북한산국립공원의 현존식생은 총 8개의 식물군락과 기타 지역으로 구분 되었으며, 자연림은 신갈나무군락, 신갈나무소나무군락, 낙엽활엽수림 등 5개 식물군락으로, 조림지는 잣나무림, 리기다소나무림, 아까시나무림 등 3개 산림유형으로 구분되었다. 북한산국립공원의 녹지자연도에서 가장 넓게 분포한 것은 8등급 지역이 약 92.8%였다. 북한산국립공원안에 식재된 수목류는 총 71과 212종류이었고 이 중 자생종은 37과 67종류(31.6%), 외래종은 58과 145종류(68.4%)이었다. 북한산국립공원의 자연환경 회복, 자생식물의 다양성 유지와 자연경관을 향상시키기 위해서는 외래수종에 대한 관리가 필요하다.

• 대한의생명과학회지
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• 제15권1호
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• pp.31-35
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• 2009

High blood pressure (BP) is the most frequent risk factor among metabolic syndrome components. The control of hypertension is very important to prevent the cardiovascular risk in metabolic syndrome. The dysfunction of calcium channel is responsible in the regulation of the vascular muscle contribution to hypertension. Calcium channel, voltage-dependent, P/Q type, alpha-1A subunit (CACNA1A) gene is located in brain and known to control the intracranial hypertension. In this study, we investigate whether the polymorphisms of CACNA1A gene is associated with hypertension. The 49 CACNA1A genotypes were determined using the Affymetrix Genotyping chip array in 92 hypertension and 279 control individuals from a Korean population. Logistic and multiple regression models were employed to analyze the genetic contributions of polymorphisms. Out of 49 polymorphisms, six SNPs (rs12611029, rs16035, rs7259944, rs10419472, rs17777900, and rs4926294) showed a significant association with hypertension in three alternative models (codominant, dominant, and recessive models; P<0.05 after adjusting for age and sex). Our results suggest that the CACNA1A gene may be associated with hypertension in the Korean population.

• 디지털융복합연구
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• 제15권2호
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• pp.251-262
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• 2017

본 연구는 Bronfenbrenner의 생태학적 체계이론을 바탕으로 대학생의 정신건강에 영향을 미치는 요인을 구분하고 통합적인 모형 구축과 정신건강 증진을 위한 간호중재 개발의 기틀을 마련하고자 한다. 연구방법은 횡단적 조사연구로 대학생을 대상으로 하였다. 일반적 특성 및 정신건강관련 특성은 SPSS 20.0 프로그램을, 모형의 적합도검증, 가설검증은 Amos 20.0 프로그램을 이용하였다. 연구결과에서 모형의 적합도 지수는 $x^2=614.90$(p=.000), Q값=3.5, GFI=.88, AGFI=.84, NFI=.92, NNFI=.94, CFI=.94, RMR=.02, RMSEA=.08 적합도를 나타내어 연구모형이 가정에 적합한 것으로 나타났다. 연구결과 정신건강에 스트레스가 가장 높은 영향을 미치고 있으며 스트레스 대처 방안과 자아 존중감, 부모의 양육태도가 정신건강에 영향을 미치는 것으로 확인되었다. 대학생의 정신건강을 증진시키기 위해서는 스트레스 관리, 자아존중감 증진, 스트레스 대처 능력 향상을 도모하는 간호중재를 개발하고, 학교현장 및 정신보건 실무에 활용하는 중재가 수행되어야 할 것으로 생각된다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.40-47
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• 2014

In this paper, $Al_2O_3$ film deposited by thermal atomic layer deposition (ALD) with diluted $NH_4OH$ instead of $H_2O$ was suggested for passivation layer and anti-reflection (AR) coating of the p-type crystalline Si (c-Si) solar cell application. It was confirmed that the deposition rate and refractive index of $Al_2O_3$ film was proportional to the $NH_4OH$ concentration. $Al_2O_3$ film deposited with 5 % $NH_4OH$ has the greatest negative fixed oxide charge density ($Q_f$), which can be explained by aluminum vacancies ($V_{Al}$) or oxygen interstitials ($O_i$) under O-rich condition. $Al_2O_3$ film deposited with $NH_4OH$ 5 % condition also shows lower interface trap density ($D_{it}$) distribution than those of other conditions. At $NH_4OH$ 5 % condition, moreover, $Al_2O_3$ film shows the highest excess carrier lifetime (${\tau}_{PCD}$) and the lowest surface recombination velocity ($S_{eff}$), which are linked with its passivation properties. The proposed $Al_2O_3$ film deposited with diluted $NH_4OH$ is very promising for passivation layer and AR coating of the p-type c-Si solar cell.

• 한국식품과학회지
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• 제21권5호
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• pp.606-612
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• 1989

한국산 바지락으로부터 새로운 렉틴을 아세톤파우더, 황산암모늄 침전, 친화력 크로마토그라피 및 FPLC의 이온교환 크로마토그라피법으로 분리 정제하였다. 이 렉틴은 사람의 적혈구를 비특이적으로 응집시켰으며, 생쥐와 토끼의 적혈구 및 생쥐의 복수 Sarcoma 180 세포를 응집시키지 않았고 사람의 말초혈관 임파구도 분열 촉진시키지 못하였다. 전기영동상에서 하나의 주된 띠로 나타났으며 분자량은 Biogel P-300겔 여과에서 131,000, SDS 전기영동상에서는 125,000으로 나타났다. Subunit는 33,000과 30,000의 다른 폴리펩타이드로 tetramer로 추정된다. EDTA에 의해서 활성이 저해된 바지락 렉틴은 $Ca^{++}$과 $Mn^{++}$에 의하여 적혈구 응집력이 회복되었다. 또한 이 렉틴은 약 4.2% 중성당을 함유한 당단백질임이 확인되었다.

• Molecules and Cells
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• 제22권3호
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• pp.314-322
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• 2006

The whole mitochondrial genome (14,915 nt) of Pollicipes mitella (Crustacea, Maxillopoda, Cirripedia, Thoracica) was sequenced and characterized. It is the shortest of the 31 completely sequenced crustacean mitochondrial genomes, with the exception of a copepod Tigriopus japonicus (14,628 nt). It consists of the usual 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 relatively short non-coding region (294 nt). The thoracican cirripeds apart from Megabalanus volcano have the same arrangement of protein-coding genes as Limulus polypemus, but there are frequent tRNA gene translocations (at least 8). Some interesting translocation features that may be specific to the thoracican cirriped lineage are as follows: 1) trnK-trnQ lies between the control region and trnI, 2) trnA-trnE lies between trnN and trnS1, 3) trnP lies between ND4L and trnT, and 4) trnY-trnC lies between trnS2 and ND1. In P. mitella there are two trnL genes (L1 and L2) in the typical crustacean positions (ND1-L1-LrRNA and CO1-L2-CO2). The present result is compared and discussed with the other three cirriped mitochondrial genomes from one pedunculate (Pollicipes polymerus) and two sessiles (Tetraclita japonica and M. volcano) published so far. Mitochondrial protein phylogenies reconstructed by the BI and ML algorithms show that the thoracican Cirripedia is monophyletic (BPP 100/BP 100) and associated with Remipedia (BPP 98/BP 35). In addition, Oligostraca, including Ostracoda, Branchiura, and Pentastomida, is a monophyletic group (BPP 99/BP 68), and is basal to all the other examined arthropods. Remipedia + Cirripedia appears as an independent lineage within Arthropoda, apart from Thoracopoda (Malacostraca, Branchiopda, and Cephalocarida). The Thoracopoda is paraphyletic to Hexapoda. The present result suggests that the monophylies of Crustacea and Maxillopoda should be reconsidered.

• Molecules and Cells
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• 제39권6호
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• pp.508-513
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• 2016

To investigate the potential therapeutic effects of polyphenols in treating Pb induced renal dysfunction and intoxication and to explore the detailed underlying mechanisms. Wistar rats were divided into four groups: control groups (CT), Pb exposure groups (Pb), Pb plus Polyphenols groups (Pb+PP) and Polyphenols groups (PP). Animals were kept for 60 days and sacrificed for tests of urea, serum blood urea nitrogen (BUN) and creatinine. Histological evaluations were then performed. In vitro studies were performed using primary kidney mesangial cells to reveal detailed mechanisms. Cell counting kit-8 (CCK-8) was used to evaluate cell viability. Pb induced cell apoptosis was measured by flow cytometry. Reactive oxygen species (ROS) generation and scavenging were tested by DCFH-DA. Expression level of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-1-${\beta}$ (IL-1-${\beta}$) and IL-6 were assayed by ELISA. Western blot and qPCR were used to measure the expression of ERK1/2, JNK1/2 and p38. Polyphenols have obvious protective effects on Pb induced renal dysfunction and intoxication both in vivo and in vitro. Polyphenols reduced Pb concentration and accumulation in kidney. Polyphenols also protected kidney mesangial cells from Pb induced apoptosis. Polyphenols scavenged Pb induced ROS generation and suppressed ROS-mediated ERK/JNK/p38 pathway. Downstream pro-inflammatory cytokines were inhibited in consistency. Polyphenol is protective in Pb induced renal intoxication and inflammatory responses. The underlying mechanisms lie on the antioxidant activity and ROS scavenging activity of polyphenols.

• 한국발생생물학회지:발생과생식
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• 제22권1호
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• pp.73-83
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• 2018

This study investigates the endoplasmic reticulum (ER) stress and subsequent apoptosis in duced during somatic cell nuclear transfer (SCNT) process of porcine SCNT embryos. Porcine SCNT and in vitro fertilization (IVF) embryos were sampled at 3 h and 20 h after SCNT or IVF and at the blastocyst stage for mRNA extraction. The x-box binding protein 1 (Xbp1) mRNA and the expressions of ER stress-associated genes were confirmed by RT-PCR or RT-qPCR. Apoptotic gene expression was analyzed by RT-PCR. Before commencing SCNT, somatic cells treated with tunicamycin (TM), an ER stress inducer, confirmed the splicing of Xbp1 mRNA and increased expressions of ER stress-associated genes. In all the embryonic stages, the SCNT embryos, when compared with the IVF embryos, showed slightly increased expression of spliced Xbp1 (Xbp1s) mRNA and significantly increased expression of ER stress-associated genes (p<0.05). In all stages, apoptotic gene expression was slightly higher in the SCNT embryos, but not significantly different from that of the IVF embryos except for the Bax/Bcl2L1 ratio in the 1-cell stage (p<0.05). The result of this study indicates that excessive ER stress can be induced by the SCNT process, which induce apoptosis of SCNT embryos.

• Journal of Microbiology and Biotechnology
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• 제18권5호
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• pp.958-963
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• 2008

A series of experiments were conducted to assess the effectiveness of rhizobacteria containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase for growth promotion of peas under drought conditions. Ten rhizobacteria isolated from the rhizosphere of different crops (peas, wheat, and maize) were screened for their growth promoting ability in peas under axenic condition. Three rhizobacterial isolates, Pseudomonas fluorescens biotype G (ACC-5), P. fluorescens (ACC-14), and P. putida biotype A (Q-7), were selected for pot trial on the basis of their source, ACC deaminase activity, root colonization, and growth promoting activity under axenic conditions. Inoculated and uninoculated (control) seeds of pea cultivar 2000 were sown in pots (4 seeds/pot) at different soil moisture levels (25, 50, 75, and 100% of field capacity). Results revealed that decreasing the soil moisture levels from 100 to 25% of field capacity significantly decreased the growth of peas. However, inoculation of peas with rhizobacteria containing ACC deaminase significantly decreased the "drought stress imposed effects" on growth of peas, although with variable efficacy at different moisture levels. At the lowest soil moisture level (25% field capacity), rhizobacterial isolate Pseudomonas fluorescens biotype G (ACC-5) was found to be more promising compared with the other isolates, as it caused maximum increases in fresh weight, dry weight, root length, shoot length, number of leaves per plant, and water use efficiency on fresh and dry weight basis (45, 150, 92, 45, 140, 46, and 147%, respectively) compared with respective uninoculated controls. It is highly likely that rhizobacteria containing ACC deaminase might have decreased the drought-stress induced ethylene in inoculated plants, which resulted in better growth of plants even at low moisture levels. Therefore, inoculation with rhizobacteria containing ACC deaminase could be helpful in eliminating the inhibitory effects of drought stress on the growth of peas.