• Mycobiology
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• 제51권3호
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• pp.139-147
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• 2023

Aspergillus sojae has long been considered a domesticated strain of Aspergillus parasiticus. This study delineated relationships among the two species and an Aspergillus PWE36 isolate. Of 25 examined clustered aflatoxin genes of PWE36, 20 gene sequences were identical to those of A. sojae, but all had variations to those of A. parasiticus. Additionally, PWE36 developmental genes of conidiation and sclerotial formation, overall, shared higher degrees of nucleotide sequence identity with A. sojae genes than with A. parasiticus genes. Examination of defective cyclopiazonic acid gene clusters revealed that the PWE36 deletion pattern was identical only to those of A. sojae. Using A. sojae SMF134 genome sequence as a reference, visualization of locally collinear blocks indicated that PWE36 shared higher genome sequence homologies with A. sojae than with A. parasiticus. Phylogenetic inference based on genome-wide single nucleotide polymorphisms (SNPs) and total SNP counts showed that A. sojae strains formed a monophyletic clade and were clonal. Two (Argentinian and Ugandan) A. parasiticus isolates but not including an Ethiopian isolate formed a monophyletic clade, which showed that A. parasiticus population is genetically diverse and distant to A. sojae. PWE36 and A. sojae shared a most recent common ancestor (MRCA). The estimated divergence time for PWE36 and A. sojae was about 0.4 mya. Unlike Aspergillus oryzae, another koji mold that includes genetically diverse populations, the findings that current A. sojae strains formed a monophyletic group and shared the MRCA with PWE36 allow A. sojae to be continuously treated as a species for food safety reasons.

• 한국직업건강간호학회지
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• 제33권3호
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• pp.129-139
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• 2024

Purpose: This study aimed to examine the differences in nurses' psychosocial work environment (PWE) in integrated nursing care wards (IWs) with higher nurse staffing and general wards (GWs) with lower staffing, and to analyze the effect of PWE on their health outcomes. Methods: Data were collected from 151 nurses in IWs and 156 nurses in GWs at a tertiary hospital in Seoul in 2023. The Korean version of the Copenhagen Psychosocial Questionnaire III was used to measure PWE and health outcomes. Regression analyses were conducted to examine the effect of PWE on health outcomes. Results: The most negative aspects of the nurses' work environment were found in the work demand domain. IW nurses (vs. GW nurses) reported lower work demand, better work organization and job contents, and a more positive work-individual interface. Nurse health outcomes were also better in the IWs. Lower work demand and better work-individual interfaces were positively associated with improved health outcomes, while ward type (IW vs. GW) was not significantly related to health outcomes. Conclusion: Reducing work demand by expanding integrated nursing care services nationwide and improving nurse staffing in GWs is crucial for improving health outcomes.

• 생명과학회지
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• 제28권4호
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• pp.421-428
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• 2018

식후고혈당은 제 2형 당뇨병의 발병에 부정적인 영향을 미치고 미세혈관 및 대혈관 질환 등의 당뇨병 합병증 유발과 밀접한 관계가 있다. 따라서 식후고혈당을 조절하는 것이 당뇨병 합병증의 위험을 줄이는 가장 중요한 요소이다. 식후고혈당은 소장에서 ${\alpha}$-글루코시다아제와 같은 탄수화물 소화 효소를 저해함으로써 조절될 수 있다. 이에 본 연구는 쇠비름 에탄올 추출물(PEE)과 물 추출물(PWE)이 탄수화물 소화 효소를 저해하고, 당뇨병 마우스에서 식후 고혈당을 강하시키는 효과에 대해 조사하였다. ${\alpha}$-글루코시다아제와 ${\alpha}$-아밀라아제에 대한 저해효과는 두 추출물 모두 양성대조군인 acarbose보다 더 효과적이었으며, PEE에 의한 ${\alpha}$-글루코시다아제 저해 효과가 PWE 보다 더 효과적이었다. Diabetic mice에 전분(2 g/kg)을 투여한 후의 혈당 증가는 30, 60, 120분에 각각 383.7, 429.3, 360.2 mg/dL로 나타났고, 전분(2 g/kg)과 PEE 또는 PWE 추출물(300 mg/Kg)을 투여한 후의 혈당 증가는 30, 60, 120분에 각각 337.0, 368.5, 290.1 mg/dL과 365.8, 379.2, 324.3 mg/dL로 나타나, PEE 추출물 투여군이 대조군에 비해 식후 혈당 강하가 효과적으로 나타남을 알 수 있었다. 이러한 결과는 쇠비름 추출물이 탄수화물 소화효소를 저해함으로써 식후 고혈당을 완화시키고, 특히 쇠비름 에탄올 추출물(PEE)이 쇠비름 물 추출물(PWE) 보다 식후 고혈당을 완화시키는데 더욱 효과가 있는 것으로 나타났다.

• 한국IT서비스학회지
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• 제14권1호
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• pp.129-143
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• 2015

This study has two goals. The first goal is to investigate whether worked examples are effective in the ill-defined domain with on-line learning and the second goal is to find out which components (conceptual or procedural knowledge) of worked examples are effective factor at the given learning environment. We carried out three experiments in which Korean undergraduate or graduate students were working in three or four conditions of worked examples (CWE, PWE, CPWE, or the control group). While experiment 1 conducted in on-line learning environment did not find any effect and difference among groups and also any logical reason for those results, experiment 2 conducted in completely controlled laboratory setting with less knowledgeable students showed the clear difference among groups by the order CPWE, PWE, and CWE. Experiment 3 in which highly knowledgeable and motivated students were presented the same materials in more controlled on-line learning environment indicated the difference among groups by the order CWE, CPWE, and PWE. The results were discussed within the framework of cognitive load theory.

• 한국자기학회지
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• 제24권5호
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• pp.135-139
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• 2014

물리적 기상합성법인 전기선폭발법을 이용하여 챔버내 산소분압을 바꾸면서 철산화물을 제조하였다. 제조된 철산화물은 산소 분압에 따라 $Fe_2O_3$ 및 $Fe_3O_4$상으로 제조되었다. 산소분압이 30 %인 경우 ${\gamma}-Fe_2O_3$와 ${\alpha}-Fe_2O_3$와 같이 $Fe^{3+}$의 형성이 용이함을 확인 하였다. 산소 분압을 15 %로 줄이면 $Fe_3O_4$가 형성되어 $Fe^{2+}$ 이온을 확인할 수 있었다. 뫼스바우어분광분석을 활용하여 ${\gamma}-Fe_2O_3$와 $Fe_3O_4$상 분석을 수행하였다. 13 K에서 295 K까지의 뫼스바우어 스펙트럼으로부터 자기정렬구조가 사라진 면적비로부터 약 12 % 정도의 ${\gamma}-Fe_2O_3$상이 초상자성 특성을 보임을 확인하였다.

• 한국분말재료학회지
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• 제18권2호
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• pp.105-111
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• 2011

This study investigated the effect of wire diameter and applied voltage on the fabrication of Ni-free Fe-based alloy nano powders by employing the PWE (pulsed wire evaporation) in liquid, for high temperature oxidation-resistant metallic porous body for high temperature particulate matter (or soot) filter system. Three different diameter (0.1, 0.2, and 0.3 mm) of alloy wire and various applied voltages from 0.5 to 3.0 kV were main variables in PWE process, while X-ray diffraction (XRD), field emission scanning microscope (FE-SEM), and transmission electron microscope (TEM) were used to investigate the characteristics of the Fe-Cr-Al nano powders. It was controlled the number of explosion events, since evaporated and condensed nano-particles were coalesced to micron-sized secondary particles, when exceeded to the specific number of explosion events, which were not suitable for metallic porous body preparation. As the diameter of alloy wire increased, the voltage for electrical explosion increased and the size of primary particle decreased.

• 한국철도학회논문집
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• 제13권3호
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• pp.339-348
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• 2010

현재 우리나라는 '국가통합교통체계효율화법'을 통해 현 교통체계의 효율성, 통합성 및 연계성을 향상 시키고자 하고 있다. 그러나 어느 정도가 편리한 연계환승인지, 또 얼마나 이용자가 많아야 시설물의 용량이 초과인지에 대한 체계적인 연구와 근거가 부족한 실정이다. 본 연구에서는 최근에 우리나라 인체 표준을 반영하여 인체타원 및 점유면적을 재산정하고 PME와 PWE를 개발하여 이를 토대로 도시철도 환승시설의 서비스수준 평가 모델을 제시하였다. 매표소와 자동발매기 이용자의 서비스수준을 결정하기 위해 대기행렬이론을 반영하여 서비스 수준을 결정하는 평가모델을 제시하였고, 환승보행시설간의 중요도를 AHP분석을 통해 산정하여 제시하였다. 실제 도시철도 5개역에 대한 현행 환승보행시설의 서비스 수준을 종합적으로 평가하여 비교, 평가하여 제시하였다.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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• pp.78-80
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• 2009

In this paper, we have described the advantages of fixed mobile convergence access network based on FTTH. Also, we have investigated the possibility of mobile backhaul based on FTTH network combined TOM over IP emulation and adaptive clock recovery technologies, and verified successful transport of both E1 TDM traffic and Clock through the packet based PON network. within the allowable tolerance.

• Journal of the Optical Society of Korea
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• 제15권3호
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• pp.283-288
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• 2011

In this study, a wide-band photonic crystal Y-splitter for TE modes is proposed. A triangular lattice of air holes etched in a GaAs slab is used as the platform. In order to numerically analyze the structures, plane wave expansion (PWE) and finite difference time domain (FDTD) methods are used. In comparison with the structures reported in the literature, the proposed topology has a less complexity while it provides more than 100nm bandwidth. The simplicity of the design, its high transmission ratio and its wide bandwidth makes it a suitable choice for the implementation of photonic crystal integrated circuits.

• 한국분말재료학회지
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• 제11권3호
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• pp.210-216
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• 2004

The possibility to decrease agglomeration of Cu nano powders and their separation during pulsed wire evaporation (PWE) process was investigated by controlling the working gas system, i.e., the design of the gas path, the type and pressure of the atmospheric gas. As a result, it was possible to choose the optimal design of the gas path providing large specific surface area and high degree of separation of the synthesized Cu nano powders. It was also shown that an Ar+10∼50$N_2$ mixture can be used in production of Cu nano powders, which do not react with nitrogen.