• 대한화학회지
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• 제65권3호
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• pp.203-208
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• 2021

As part of our attempt to discover novel active compounds against multi-drug resistant pathogens, we hereby report two new complexes of iron(III) with formulae: [Fe(L₁)₂(H₂O)₂]Cl₃ and [Fe(L₁)₂(L₂)(H₂O)]Cl₂ where L₁ = 1,10-phenanthroline (C₁₂H₈N₂) and L₂ = guanide (C₅H₄N₅O^-). The synthesized complexes were characterized using spectroscopic analysis (ESI-MS, ICP-OES, FT-IR, and UV-Vis), cyclic voltammetry, CHN analysis, gravimetric chloride determination, melting point determination, and conductance measurement. Octahedral geometries are assigned to both complexes. In vitro antibacterial activity was tested on two Gram-positive (Staphylococcus aureus, Streptococcus epidermidis) and two Gram-negative (Escherichia coli and Klebsiella pneumoniae) bacteria using the disc diffusion method. The complexes demonstrated appreciable activity against these pathogens. Interestingly, the [Fe(L₁)₂(L₂)(H₂O)]Cl₂ complex manifested a higher degree of inhibition against the drug-resistant Gram-negative bacteria than the commercially available drug, namely erythromycin.

• 한국작물학회지
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• 제48권6호
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• pp.501-505
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• 2003

보리호위축병 피해지역에 대한 수량감소의 예측을 위하여, 보리호위축병(BaYMV)에 대한 저항성 품종과 이병성 품종간 수량구성요소, 수량 및 증질 변이를 건전구와 이병구에서 비교 조사하였다. 1. 보리호위축병의 이병주는 BaYMV에 감염된 것으로 나타났으며, 이병정도는 감수성 품종인 백동에서 9, 저항성 품종인 내한쌀보리에서 1정도 발병하였다. 2. 감수성 품종인 백동은 천립중을 제외한 간장, 수당립수, $\textrm{m}^2$당 수수 등의 수량구성요소가 유의하게 감소하였으며, 수량은 대조구의 20%수준으로 현저히 감소하였다. 3. 보리호위축병 감염구에서 종자의 발아율은 감수성 품종과 저항성 품종간에 차이가 없었으나, 정립률은 감수성 품종인 백동에서 설립중이 유의하게 증가하였으며, 대조구에 비하여 정립률과 조단백질 함량 모두 유의한 차이를 보였다. 4. 보리호위축병은 간장, 수량, 정립률, 수수, 천립중, 1수립수 등의 피해와 부의 상관을, 조단백질 함량과는 정의 상관을 보여 보리호위축병에 이병이 되면 수량 및 품질에 크게 피해를 주는 것으로 나타났다.

• 한국해양공학회지
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• 제24권4호
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• pp.23-31
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• 2010

The flow around a remotely-operated vehicle (ROV) has been investigated numerically to improve the resistant performance by modifying the hull form of the ROV. In the case of the base hull form considered in this study, form drag rather than friction drag was the dominant component of total drag. Subsequently, the surfaces that were most susceptible to local pressure effects were modified to give them a more streamlined shape. Eleven different hull forms were chosen to undergo surface modification for drag reduction. In addition, four different boat-tail appendages with different slant angles were installed at the stern to reduce the wake vortices that are induced by the local regions of very low pressure. Consequently, a total of 11 different hull forms for drag reduction were considered. The final hull form, which combined the hull for which surface modification resulted in the lowest drag with a boat-tail appendage with a 15-degree slant angle, resulted in a drag reduction of 20%.

• 대한조선학회 특별논문집
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• 대한조선학회 2006년도 특별논문집
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• pp.46-52
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• 2006

For ships, heat resistant coating is applied on the aluminized steel pipe systems dealing with high temperature steam over $200^{\circ}C$. The coatings on these steam pipes should retain both heat resistance and anti-corrosion properties to provide long-term resistance against coating defects (rust, delamination and crack) under the harsh outdoor environment including repeated seawater wetting and condensation. Thus, it is important to improve the coating qualities and to reduce maintenance works for these steam pipe systems. In this study, five different commercial heat resistant coatings (A, B, C, D, E) were selected for evaluation. Various physical properties of these coatings were evaluated on the coatings applied on the aluminized steam pipes. FT-IR analysis was also employed to identify the factors contributing the degree of heat resistance and durability of each coating material. The results indicated that the heat resistance capacity of coatings increased with the increase of silicon content as well as the decrease of substituent content. Both products C and D showed the best coating qualifies, which can be standard coating systems for future steam pipe areas.

• Journal of Microbiology and Biotechnology
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• 제11권5호
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• pp.831-837
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• 2001

Pediocin K1, a bacteriocin produced by Pediococcus sp. K1 isolated from Korean traditional fermented flatfish, inhibited certain strains of Lactobacillus, Streptococcus, and Listeria monocytogenes. Pediocin K1 was found to be stable at $90^{\circ}C$ for 30 min. Among the organisms tested, Listeria monocytogenes was the most sensitive to pediocin K1 and was completely killed when the initial inoculum size of L.monocytogenes cells was equal to or less than $10^3 CFU/ml$. The degree of inibition of Listeria monocytogenes by pediocin K1 increased 10-fold on the addition of citric acid ($0.2\%$) to the medium, thereby showing the synergistic effect of citric acid. Listeria monocytogenes cells resistant to pediocin K1 appeared at a frequency of about $10^-4$/cells. Once developed after exposure to pediocin K1, the resistant phenotype still persisted in the absence of pediocin K1 in successive cultures. This infers that resistance may be attributable to genetic change(s) in the resistant cells.

• The Plant Pathology Journal
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• 제31권2호
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• pp.132-139
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• 2015

Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes.

• The Plant Pathology Journal
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• 제28권2호
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• pp.149-155
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• 2012

A field trial was conducted in 2009/2010 and 2010/2011 growing seasons at Giza Agricultural Research Station to examine correlations between some biochemical componets and powdery mildews ($PM_s$) resistance in flax cultivars. Nine flax cultivars could be divided into five distinct groups, i.e., highly susceptible (Cortland and C.I. 2008), moderately susceptible (Giza 7, and Marshall), moderately resistant (Cass), resistant (Koto, Dakota and Wilden), and highly resistant (Ottowa 770B). The cultivars showed considerable variation in PM severity ranged from 8.05 on Ottowa 770B to 97.02% on Cortland. Total soluble proteins, total phenols, antioxidant enzymes (peroxidase and polyphenoloxidase), ascorbic acid, tocopherol, and malondialdehyde (MDA), were determined in uninfected leaves of the tested cultivars. Pearson's correlation coefficient was calculated to measure the degree of association between PM severity and each component. All components showed significant (P < 0.05) or highly significant (P < 0.01) negative correlation with PM severity except MDA, which showed positive correlation (P < 0.01). Linear regression analysis was used to evaluate the causal relationship between the biochemical components (independent variables) and PM severity (dependent variable). Coefficient of determination ($R^2$) values of the generated models ranged from 48.76 to 77.15%. Tocopherol, MDA, and proteins were the most important contributors to the total variation in PM severity as the $R^2$ values of their models were 71.78, 75.28, and 77.15%, respectively. The results of the present study suggest that tocopherol, MDA, and proteins in uninfected leaves can be used as biochemical markers to predict PM resistance in flax.

• 폴리머
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• 제30권2호
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• pp.158-161
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• 2006

본 연구에서는 고온 고압하의 반응기내에서 일차 아민(primary amine)과 PMMA의 이미드화 반응을 유도하여 내열성 플라스틱 광섬유(plastic optical fiber, POF) 재료인 polyglutarimide(PGI)를 제조하였다. 에틸 아민과 이소프로필 아민, 두 종류를 사용하였으며, 반응시 함량을 다르게 하여 합성한 후 PGI의 여러 가지 물성을 비교하였다. $^1H$ NMR과 FTIR을 사용하여 PGI의 이미드 전환율을 비교하였고, DSC와 TGA를 통해 열적 특성을 조사하였다. 에틸 아민을 사용하여 합성된 PGI 화합물들이 높은 이미드 전환율을 보이면서 향상된 내열성을 나타내었다. POF재료로서 필수적인 광학적 성질은 분광광도계와 아베굴절계로 굴절률과 광 투과율을 조사하였다. 대부분의 PGI는 PMMA 수준의 광 투과율을 유지하였으며, 보다 높은 굴절률을 나타내었다. 이것은 합성된 PGI가 POF 코어물질로써 우수한 광 효율 및 내열성 향상에 기여할 수 있음을 의미한다.

• 중환자간호학회지
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• 제11권1호
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• pp.89-100
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• 2018

Purpose : The purpose of this study was to analyze factors influencing the adherence to guidelines for intensive care unit (ICU) nurses to control infections due to multidrug-resistant organisms (MDRO). Method : Participants were 194 ICU nurses at 3 university hospitals. Questions for the survey inquired about attitude, subjective norms, perception of patient safety culture to carry out MDRO management guidelines, perceived behavior control (PBC), and intention, based on the theory of planned behavior. Path analysis were utilized. Results : The path analysis presented that PBC, perception of patient safety culture, and intent had a direct effect on MDRO management guidelines. Attitude towards following the manual did not have any correlation. The hypothetical model based on the theory of planned behavior was revealed as applicable; the degree of the variance in explaining adherence to the manual was 23 %, and the variance in explaining intention to fulfill the manual was 33 %. Conclusion : The results of this study suggest that we should develop a program to improve PBC to increase adherence to MDRO management guidelines. ICU nurses' perceptions of patient safety culture should also be surveyed.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.49-49
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• 2020

Bacterial leaf blight (BLB), caused by X. oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice due to its high epidemic potential. Understanding BLB resistance at a genetic level is important to further improve the rice breeding that provides one of the best approaches to control BLB disease. In the present investigation, a total of 10,000 accessions of rice germplasm were tested to resistance degree of four Korean isolated races (K1, K2, K3 and K3a) of Xoo by bioassay and a diverse 268 accessions was selected to the genome-wide association study (GWAS) using high quality 34,724 SNPs to identify the associated with resistance loci. LOC_Os04g53160 of chromosome 4 was significantly associated with K1 race resistant. LOC_Os11g46230 and LOC_Os11g47150 of chromosome 11 were highly associated with K2 and K3 races as 23.7 and 27.4 of -log(P) value, but K3a resistant loci was weakly associated at LOC_Os03g55270 of chromosome 3. The results of the GWAS validate known gene of BLB resistant and identified novel loci of R genes that provide useful targets for further investigation to help the breeding system and identified gene and QTL provide valuable sources for further functional characterization.