• 생태와환경
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• 제46권2호
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• pp.234-240
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• 2013

$CO_2$ 농도 증가에 의한 지구온난화는 식물의 생장과 발달에 영향을 미친다. 이에 우리나라의 우점종인 소나무, 가로수로 많이 쓰이는 은행나무 그리고 난대림의 우점종인 종가시나무와 멸종위기 식물로 지정된 개가시나무, 미선나무의 유식물을 대상으로 $CO_2$ 농도와 온도증가를 증가시킨 지구온난화 처리구와 대조구로 나누어 실험을 하였다. 2010년 4월부터 2011년 11월까지 지상부 길이와 잎 수를 측정하였다. 그 결과 소나무, 은행나무 그리고 종가시나무의 지상부 생장량은 대조구와 지구온난화 처리구에서 차이가 없었다. 개가시나무와 미선나무의 지상부생장량은 대조구보다 처리구에서 높았으나, 잎 수는 $CO_2$ 농도와 온도증가에 의해 영향을 받지 않았다. 이상으로 볼 때, 지구온난화 조건이 되면 우점하고 있는 소나무, 은행나무, 종가시나무보다 멸종위기식물인 미선나무와 개가시나무의 지상부 생장에 유리할 것이다.

• 한국화재소방학회논문지
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• 제24권5호
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• pp.39-49
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• 2010

본 연구에서는 담뱃불에 의한 낙엽 착화 특성에 대해 실험과 수치 해석을 이용하여 담뱃불로 인한 산불 발생 위험성에 대해 구명하고자 한다. 실험 방법은 P. densiflora와 Q. variabilis 2종의 낙엽에 대해 수분함유량, 풍속, 바람방향 대비 담뱃불 위치, 낙엽에서의 담뱃불 위치, 담배 굵기, 낙엽의 부서짐 정도, 경사조건 등 총 2,304 조건에 대해 5회 반복실험을 실시하였다. 낙엽의 온도변화는 전산수치해석을 통해 분석하였다. 실험 결과, 전체 2,304 조건의 실험에서 약 8.6%인 197조건에서 발화가 되었고 각 조건별 5회 반복실험에서 모두 발화된 최적조건은 전체의 약 0.6%인 13조건으로 조사되었다. 담뱃불로 인해 100% 발화가 가능한 최적 조건은 수분함유량 15% 미만, 부서진 낙엽상태, 풍속 2.0m/s 이상, 담뱃불이 낙엽에 덮여 있는 조건이 일치할 경우인 것으로 분석되었다. 열전달 수치해석을 이용한 Q. variabilis 낙엽의 온도변화를 분석한 결과, 담뱃불 부근의 낙엽 바닥면에서 약 $307^{\circ}C$(Max. $317^{\circ}C$) 이상 온도가 지속 되는 것으로 나타났다. 따라서 Q. variabilis의 자연발화 및 착화온도가 각각 $307^{\circ}C$, $305^{\circ}C$인 것에 비추어 담뱃불로 인한 발화가 가능한 것으로 분석되었다.

• 한국전기전자재료학회논문지
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• 제19권7호
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• pp.655-661
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• 2006

Dielectric and piezoelectric properties of PMN-PZT ceramics with a high mechanical quality factor$(Q_m)$ and a low temperature sintering temperature were investigated as a function of PZN substitution in order to develop multilayer piezoelectric transformer for AC-DC converter. Multilayer piezoelectric transformers were subsequently manufactured using the PMN-PZN-PZT ceramic offering the optimal behavior and then the electrical performance were invetigated. At the sintering temperature of $940^{\circ}C$, density, electromechanical coupling factor$(k_p)$, mechanical qualify factor$(Q_m)$ and dielectric constant$(\varepsilon_r)$ of 8 mol% PZN substituted specimen were $7.73g/cm^3$, 0.524, 1573 and 1455, respectively. The PZN substitution caused a increase in the dielectric constant and the electromechnical coupling factor. The voltage step-up ratio of multilayer piezoelectric transformer showed the maximum value at near the resonant frequency of 76.55 kHz and increased according to the increase of load resistance. The multilayer piezoelectric transformer with the output impedance coincided with the load resistance showed the temperature increase of less than $20^{\circ}C$ at the output power of 10 W. Based on the results, the manufactured multilayer transformer using the low temperature sintered PMN-PZN-PZT ceramics can be stably driven for both step-up and down transformers.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.309-312
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• 2004

We performed exon trapping in order to locate functional genes on chicken chromosomes (GGA) and to identify functional gene sequences from chicken cosmids. Sequence analysis of 100 clones revealed 17 putative exons, five of which were identified with known sequences in a gene database search: thymopoietin beta (TMPO), U5 snRNP-specific 40 kDa protein (HPRP8BP), dihydropyridine receptor alpha 1 subunit (CACNL1A3), cystein string protein (CPS) and C15orf4. We attempted to map the genes to chicken chromosomes by using FISH and linkage analysis. The chromosomal localizations were GGA1 (TMPO), GGA10 (C15orf4), GGA23 (HPRP8BP) and GGA28 (CPS) by FISH and linkage analysis, while that of CACNL1A3 was predicted to be on a microchromosome by FISH but not by linkage analysis. Comparative mapping analyses between chickens and humans for the genes revealed both known and new synteny. The syntenic conservation between GGA1 and human chromosome (HSA) 12q23 (TMPO) and between GGA10 and HSA15q25 (C15orf4), were consistent with a recent publication, while two new syntenies were observed between GGA28 and HSA20q13.3 in CPS and between GGA23 and HSA1p34-35 in HPRP8BP. The information of presently mapped genes can contribute as anchor markers based on functional genes and the construction of a comparative map.

• 임산에너지
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• 제7권1호
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• pp.11-21
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• 1987

잣나무림과 신갈나무림의 물질생산량과 영양물질의 현존량을 추정하기 위하여 경기도 광주군 도척면에 위치하는 22년생 임지에 10x10m 조사구 10개씩을 설치하여 직경급을 안배한 표목본 10주씩을 벌목, 간(Ws), 지(Wb), 엽(Wl) 부위로 나누어 건중량을 측정, $D^2H$와 건중량과의 상대생장식에 의해 물질생산량을 추정하였다. 생산구조면에서 광합성부가 잣나무는 지상 4.2m, 신갈나무는 지상 6.2m에서 시작되었고, 수관의 최대광합성층은 각각 7.2m, 9.2m에서 출현하였다. 잎, 가지, 줄기의 건중량과 $D^2H$와의 상대생장식에서 두 수종 모두 유의성이 인정되었다. 현존량은 잣나무림이 152.07ton/ha(지상부 124.92ton/ha, 지하부 27.15t/ha), 신갈나무림이 156.02t/ha(지상부 120.65t/ha, 지하부 35.37t/ha)이었고, 연간순생산량은 각각 24.66t/ha$\cdot$yr이었고, 간재생산능률은 각각 0.62kg/kg$\cdot$yr, 1.10kg/kg$\cdot$yr이었다. 영양물질의 현존량은 잣나무림에서는 질소, 칼슘, 마그네슘은 대부분이 광물질토양층($0\~30$cm)에, 인과 카리는 교목층에 대부분이 함유되어 있었으며, 신갈나무림에서는 질소, 인, 카리, 마그네슘은 대부분이 광물질토양층에, 칼슘은 대부분이 교목층에 분포하였다. 8개월간($3\~11$월)에 채취된 낙엽량은 잣나무림에서 4.013t/ha, 신갈나무림에서 3.490t/ha이었다.

• 대한간호학회지
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• 제33권8호
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• pp.1127-1134
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• 2003

Background. Although there have been a great number of research studies based on the model of uncertainty in illness, few studies have considered the appraisal portion of model. Purpose. The purpose of this study was to test the mediating effect of appraisal in the model of uncertainty in illness. Additionally, this study aimed to examine the relationships among uncertainty, symptom severity, appraisal, and anxiety in patients newly diagnosed with atrial fibrillation. Methods. This study employed a descriptive correlational and cross-sectional survey design using a face-to-face interview method. Patients diagnosed with atrial fibrillation within the previous 6 months prior to data collection were interviewed by Mishel Uncertainty in Illness Scale-Community Form, appraisal scale, Symptom Checklist-Severity V.3, and State Anxiety Inventory. Results. A total of 81 patients with atrial fibrillation were recruited from two large urban medical centers in Cleveland, Ohio, U.S.A.. Symptom severity was the significant variable in explaining uncertainty ($\beta$=0.34). Individuals with greater symptom severity perceived more uncertainty. Uncertainty was appraised as a danger rather than opportunity, and those with greater uncertainty appraised a greater danger (p<.0l). While the appraisal of opportunity had the negative relationship with anxiety (r=-0.25), the appraisal of danger was positively associated with anxiety (r=0.78). The measure of goodness of fit (Q) of the model was .7863, and the significant test (X$^2$) for the Q was statistically significant (df =3, p<.00l). Accordingly, the overall mediating model of uncertainty in illness was proven not to be fit to the empirical data of patients with atrial fibrillation. Consequently, the mediating effect of appraisal was not supported by the empirical data of this study. Conclusion. The findings of this study were discussed in terms of their relevance compared with those of previous studies or theoretical framework and the plausible explanations on study findings. Lastly, in order to expand the present body of knowledge on uncertainty in illness model, recommendations for the future nursing studies were included.

• 대한임상검사과학회지
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• 제40권2호
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• pp.98-105
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• 2008

Colorectal carcinoma from various cancers is fourth ranked occurred to Korean. Due to western dietary life, this cancer has been increased continuously. Therefore, the further study will be needed to find a candidate gene involved in the development and progression of colorectal carcinoma as well as to diagnose and treatment helpfully. The purpose of this study was designed to find a carcinogenesis gene using microsatellite marker on chromosomes 7th and 20th from 30 colon cancer patients. The amplification was investigated in order of D20S97 57% (17/30), D20S101 57% (17/30), D20S119 53% (16/30), D7S483 50% (15/30), D7S495 47% (14/30), D7S498 47% (14/30). The genetic mutation pattern depends on loci of colorectal carcinoma was shown highly amplified with 3.77 from colon cancer than with 2.08 from right colorectal carcinoma (P<0.018). The genetic mutation with lymph nodes was investigated higher with 4.13 at metastasized group than with 1.93 at non-metastasized group (P<0.001). There was no difference at comparison between histological classfication and serological CEA increase as well as on genetic mutated pattern depends on disease stage. It is suggested that the amplification on chromosomes 7q and 20q determines a pivotal role from first stage to metastasis cancer and also functions as an useful marker on diagnosis and treatment of colorectal carcinoma patients as well as follow-up checkup. Recently, the diagnosis and study using genetic analyzer are necessary for efficient application. Fortunately, several university hospitals run this genetic analyzer currently so it is expected that this method makes full use of clinical application.

• 한국식품영양과학회지
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• 제39권11호
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• pp.1654-1659
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• 2010

오징어 가공 부산물인 오징어 간의 효율적 이용을 위하여 오징어 간을 이용하여 액젓을 제조하고 이들 액젓의 ACE 저해효과를 살펴보았다. 액젓의 ACE 저해활성은 12개월까지는 점차적으로 증가하였으나 그 이후에는 저해활성이 둔화되어 거의 일정한 저해활성을 유지하였다. 숙성 액젓 중 15개월째 액젓($IC_{50}=29.66\;{\mu}g$)을 한외여과막으로 통과시켜 회수한 분자량 10,000 Da 이하의 저분자물질을 Bio-gel P-2 gel chromatography를 행하여 ACE 저해효과를 가지는 3개획분을 분취하였다. 이들 획분 중에서 ACE 저해효과가 가장 높은 B 획분을 SuperQ-Toyopearl 650S column을 이용한 음이온 교환크로마토그래피에 의해 B-1의 활성획분을 분리하였다. 획분 B-1의 아미노산 조성은 lysine, glycine 및 proline의 함량이 가장 많아 전체의 약 85%를 차지하였으며 $IC_{50}$은 $5.46\;{\mu}g$으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1605-1612
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• 2016

Quinolone-resistant Salmonella strains were isolated from patient samples, and several quinolone-sensitive strains were used to analyze mutations in the quinolone resistance-determining region (QRDR) of gyrA, gyrB, parC, and parE and to screen for plasmid-mediated quinolone resistance. Among the 21 strains that showed resistance to nalidixic acid and ciprofloxacin (MIC 0.125-2.0 μg/ml), 17 strains had a mutation in QRDR codon 87 of gyrA, and 3 strains had a single mutation (Ser83 → Phe). Another cause of resistance, efflux pump regulation, was studied by examining the expression of acrB, ramA, marA, and soxS. Five strains, including Sal-KH1 and Sal-KH2, showed no increase in relative expression in an analysis using the qRT-PCR method (p < 0.05). In order to determine the genes involved in the resistance, the Sal-9 isolate that showed decreased susceptibility and did not contain a mutation in the gyrA QRDR was used to make the STM (MIC 8 μg/ml) and STH (MIC 16 μg/ml) ciprofloxacin-resistant mutants. The gyrA QRDR Asp87 → Gly mutation was identified in both the STM and STH mutants by mutation analysis. qRT-PCR analysis of the efflux transporter acrB of the AcrAB-TolC efflux system showed increased expression levels in both the STM (1.79-fold) and STH (2.0-fold) mutants. In addition, the expression of the transcriptional regulator marA was increased in both the STM (6.35-fold) and STH (21.73-fold) mutants. Moreover, the expression of soxS was increased in the STM (3.41-fold) and STH (10.05-fold) mutants (p < 0.05). Therefore, these results indicate that AcrAB-TolC efflux pump activity and the target site mutation in gyrA are involved in quinolone resistance.

• 대한전자공학회논문지SD
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• 제47권3호
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• pp.51-57
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• 2010

IEEE 802.11n 기반 무선 LAN과 IEEE 802.16e 기반 Mobile WiMAX에 적용할 수 있는 이중모드 직접 변환 수신기를 $0.13\;{\mu}m$ RF CMOS 공정을 이용하여 설계하였다. 설계된 직접 변환 수신기는 2.3-2.7 GHz의 주파수 범위에서 동작을 한다. 저잡음 증폭기에 Current Steering 기술을 사용하여 전체 이득의 크기를 3 단계로 조절이 가능하게 하였다. 플리커 잡음 영향을 낮추기 위해 믹서에 Current Bleeding 기술을 사용하였다. 믹서 LO를 위한 I/Q 위상 신호 발생을 위해 주파수 2-분주회로를 포함하였다. 제작된 직접 변환 수신기는 1.4V의 공급 전원에서 LO 버퍼를 포함하여 56 mA를 사용하며, 32 dB의 전력이득과 4.8dB의 잡음지수, 그리고 +6 dBm의 출력 $P_{1dB}$를 가진다.