Paleohydrologic Activity and Environmental Change on Mars

김경자,Dohm, James M.,Kim, Kyeong-Ja 한국제4기학회 2009 제사기학회지 Vol.23 No.1

Results from the most recent decade of Mars' missions to Mars highlight a liquid water and water-ice sculpted landscape. Evidence includes layered sedimentary sequences with weathered outcrops, debris flows, fluvial valleys, alluvial fans, deltas, glacial and periglacial landscapes, and geochemical/mineralogical signatures of aqueous activity, including the formation of sulfates and clays, and the leaching and deposition of elements such as potassium, thorium,and iron. Such evidence indicates weathered zones and possible paleosols in stratigraphic sequences, transport of water and rock materials to sedimentary basins, and the possible formation of extensive transient lakes and possibly transient oceans on Mars. This new evidence is consistent with Viking-era geologic investigations that reported magmatic-driven flooding, ponding to form large water bodies in the northern plains, and transient (tens of thousand of years) hydrological cycles. It may even indicate aqueous activity at present. Both endogenic (magmatic driven) and exogenic (both impact cratering and changes in orbital parameters) have influenced paleohydrologic and environmental change on Mars. Abundance of water and dynamic activity would be decisively important for the possibility of past and present life on Mars.

장기요양시설 요양보호사의 감염관리 수행에 영향을 미치는 요인

김경자,박성원,Kim, Kyoung Ja,Park, Sung Won 한국가정간호학회 2016 가정간호학회지 Vol.23 No.2

Purpose: The purpose of this study was to investigate factors influencing health workers' infection management behavior in long-term care facilities. Methods: A descriptive cross-sectional survey was conducted with 180 health workers who are employed in long-term care facilities. The data were collected from April, 25 until July, in 2016. Results: Infection management behavior positively correlated with the perceived importance of infection management (r=.77, p<.001), but role conflict negatively correlated with infection management behavior (r=.28, p<.001). The hierarchical regression model with general characteristics (first step) and perceived importance of infection management, work environment, and role conflict (second step) against infection management behavior was statistically significant (F=31.93, p<.001). This model could explain 62.8% of infection management behavior ($R^2=.62$, ${\Delta}R^2=.39$). Particularly, perceived importance of infection management was identified as factors influencing infection management behavior(${\beta}=.70$, p<.001). Conclusion: The findings of this study imply that systemic education about infection control and monitoring should be considered, so as to encourage proper infection management behaviors among health workers in long-term care facilities.

전국 병원 수술실 시설 및 운영실태에 관한 조사연구 <하>

김경자,정기선,Kim, Gyeong-Ja,Jeong, Gi-Seon 대한병원협회 1991 대한병원협회지 Vol.20 No.10

미국의 주거소비규범에 관한 연구

김경자,정순희 ( Kyung Ja Kim,Soon Hee Joung ) 대한가정학회 1995 Family and Environment Research Vol.33 No.3

전국 병원 수술실 시설 및 운영실태에 관한 조사연구 <상>

김경자,정기선,Kim, Gyeong-Ja,Jeong, Gi-Seon 대한병원협회 1991 대한병원협회지 Vol.20 No.9

Strepfomyces lincolnensis M-20 균주로 부터 분리, 정제된 L-Asparaginase의 열안정성과 단백 가수 분해 효소에 대한 저항성

김경자,Kim, Kyoung-Ja 대한약학회 2007 약학회지 Vol.51 No.3

Thermostable asparaginase was purified to homogeneity from mesophilic Strepfomyces lincolnensis M-20 by 30${\sim}$70% ammonium sulfate precipitation and asparagine-Sepharose CL 6B affinity column chromatography, The apparent molecular mass of L-asparaginase by SDS-PAGE was found to be 47 kDa, whereas by its mobility on Sephacryl S-300 column was around 180 kDa, indicating that the enzyme at the native stage acts as tetramer, The purified enzyme showed a single band on acrylamide gel electrophoresis. The optimum pH and temperature were pH 9.5 and 55${\circ}$C, respectively. Chemical modification experiments of purified asparagines implied the existence cystein residue located at or near active site. Purified asparaginase retained the 85% of the initial activity after incubation at 90${\circ}$C for 30 min. A correlation between themostability and resistance to proteolysis of commercial asparaginase and purified asparaginase from Strepfomyces lincolnensis M-20 was investigated. Purified thermostable asparaginase was resistant to trypsin and chymotrypsin treatment, while the commercial asparaginase was not themostable and was susceptible to proteolytic treatment with trypsin and chymotrypsin.

한미FTA에 대한 소비자전망과 소비자태도

김경자,Kim, Kyung-Ja 한국가정관리학회 2009 가정과삶의질연구 Vol.27 No.6

This study examined the expectations and attitudes of urban Korean consumers with respect to the Korea-USA Free Trade Agreement (FTA), which was drafted on April, 2007. The data were collected through online surveys in which 527 adults answered structured questionnaires. The results showed that the number of consumers who favored the Korea-U.S.A. FTA was almost twice the number of those who objected to it. Most of the consumers surveyed expected not only positive effects but also negative ones from the FTA, and the more consumers expected positive effects from the FTA, the more they tended to have positive attitudes toward the trade agreement. The effects of consumers' individual characteristics on their expectations and attitudes were also analyzed in this experiment.

경기 일부 지역 중학생의 성별에 따른 급식인식 및 급식 품질 속성 비교 분석

김경자,이보숙,박문경,Kim, Kyung-Ja,Yi, Bo-Sook,Park, Moon-Kyung 한국학교보건학회 2010 韓國學校保健學會誌 Vol.23 No.2

Purpose: This study was conducted to find ways to improve foodservice quality and satisfaction of middle school students in school lunch service. Recognition of concerns about school lunch and quality attributes was evaluated by gender. And we tried to investigate quality attributes which could affect degree of foodservice satisfaction by gender. Methods: Two hundred students from each of 6 middle schools (3 schools in urban and 3 schools in rural) in Gyeonggi Province were surveyed using self-developed questionnaires. Total of 1,103 questionnaires (male 556 and female 547) were collected and data were analyzed using descriptive analysis, t-test, cross table and stepwise multiple regression by SPSS 11.0. Results: There were not significant differences in average importance scores (male 4.09, female 4.06) and average performance scores (male 3.36, female 3.30) of quality attributes between middle school boys and girls. But there were significant differences in 7 and 6 of 25 quality attributes in evaluating importance and performance respectively by gender. There was not a significant difference (male 3.13, female 3.24) in degree of foodservice satisfaction by gender. But there were significant differences in the distribution of satisfaction. Stepwise multiple regression analysis showed that degree of satisfaction was influenced by a taste of food, quick complaint handling, providing favorite foods, and food hygiene in male students (F=$51.1^{***}$, adjusted $R^2$=.265). Degree of satisfaction was influenced by a taste of food, providing favorite food, proper meal prices, providing a wide variety of food in female students (F=$91.4^{***}$, adjusted $R^2$=.399). Conclusion: We found out that there were significant differences in quality attributes when evaluating importance and performance and in quality attributes which could affect foodservice satisfaction by gender.

Effect of plasmid curing on the production of siderophore from glutamic acid as both carbon and nitrogen sole sources in Acinetobacter sp. B-W

김경자,이재림,양용준,Kim, Kyoung-Ja,Lee, Jae-Rim,Yang, Yong-Joon The Microbiological Society of Korea 2018 미생물학회지 Vol.54 No.3

Effect of plasmid curing of Acinetobacter sp. B-W on the production of siderophore from glutamic acid as both carbon and nitrogen sole sources was investigated. Plasmid cured mutant of strain B-W lost the ability to produce siderophore from glutamic acid at $28^{\circ}C$. Transformant E. coli $DH5{\alpha}$ harboring 20 kb plasmid, that was isolated from wild type of strain B-W produced siderophore from glutamic acid as both carbon and nitrogen sole sources at $28^{\circ}C$, but, not at $36^{\circ}C$. Production of siderophore from glutamic acid by transformant E. coli $DH5{\alpha}$ was completely inhibited by $10{\mu}M\;FeCl_3$. In previous report, catechol nature of siderophore produced from glutamic acid by strain B-W was detected by Arnow test. The siderophore produced from glutamic acid by transformant E. coli $DH5{\alpha}$ was also catechol type. Rf value of siderophore produced from transformant E. coli $DH5{\alpha}$ grown in medium glutamic acid as both carbon and nitrogen sole sources at $28^{\circ}C$ was 0.32 in butanol-acetic acid-water (12:3:5) as developing solvent. Rf value of the siderophore was the same with that of wild type of strain B-W. Thus a single plasmid of 20 kb seemed to be involved in the production of siderophore from glutamic acid. 플라스미드가 제거된 Acinetobacter sp. B-W 균주의 돌연변이체를 글루탐산을 유일한 탄소 원과 질소원으로 함유한 배지에 $28^{\circ}C$에서 배양한 결과 글루탐산으로부터의 시드로포어 생산이 억제되었다. B-W 원 균주의 20 kb 플라스미드를 가진 형질 전환체 대장균 $DH5{\alpha}$는 같은 조건의 배지에서 시드로포어를 생산하는 것으로 조사되었다. 그러나 $36^{\circ}C$에서는 형질 전환체 대장균 $DH5{\alpha}$의 시드로포어 생산이 강하게 억제되었으며, 돌연변이체 B-W 균주는 $28^{\circ}C$에서와 마찬가지로 $36^{\circ}C$에서도 시드로포어를 생산하지 못하였다. 형질 전환체로부터 생산된 시드로포어의 종류는 원 균주 B-W와 마찬가지로 Arnow 시험 결과 카테콜 형으로 조사되었으며, $10{\mu}M\;FeCl_3$를 첨가한 배지에서는 시드로포어 생산이 완전히 억제되었다. 형질전환체로부터 생산된 시드로포어의 TLC상에서의 Rf값은 butanol-acetic acid-water (12:3:5) 용매상에서 0.32로 원 균주 B-W에서 생산된 시드로포어와 같았다. 위와 같은 실험 결과로 글루탐산으로부터 생산된 시드로포어의 생합성에 관여하는 유전자들이 20 kb 플라스미드 상에 있는 것으로 추정되었다.

장반감기 우주선유발 동위원소, $^{10}Be$과 그 응용

김경자,우형주,Kim, K.J.,Jull, A.J.T,Woo, H.J. 한국제4기학회 2006 제사기학회지 Vol.20 No.2

반감기가 긴 $^{10}Be$ (Beryllium-10)은 지구의 대기뿐만 아니라, 지구의 표면 그리고 다른 행성의 대기와 표면에서도 생성된다. 가속기질량분석기술(AMS)이 1970년 후반기에 개발되면서 지질분야 연구에서 매우 중요한 추적자 중의 하나인 $^{10}Be$ 측정이 가능해졌으며, 이후 지구와 지구외 시료를 이용한 다양한 $^{10}Be$ 응용연구가 방사성탄소 응용연구와 함께 이루어져 왔다. 본 논문은 지구와 행성의 대기와 표면에서의 $^{10}Be$ 생성에 관한 메카니즘과 지형학, 해양학, 고고학, 빙하학, 우주방사화학, 기후학, 그리고 행성학 등의 여러 학문 분야에서의 $^{10}Be$의 응용연구들에 대하여 정리하였으며, 아울러 $^{10}Be$ 가속기질량분석을 이용한 향후 연구과제들을 고찰하였다. The long-lived radionuclide, $^{10}Be$, is produced by cosmic-ray effects in the atmosphere of the earth as well as its surface and that of other planetary surfaces and atmospheres. Accelerator mass spectrometry (AMS) was developed in late 1970s, which made $^{10}Be$ terrestrial measurements more feasible. Since then, many research applications of $^{10}Be$ for both terrestrial and extraterrestrial applications have been developed, which parallel the wide range of radiocarbon ($^{14}C$) research applications. This paper summarizes production mechanisms of $^{10}Be$ both in the atmosphere and on the surface of terrestrial and extraterrestrial environments and also provides numerous $^{10}Be$ research applications in the fields of geomorphology, oceanography, archaeology, glaciology, cosmochemistry, climatology, and planetary science. We also review some $^{10}Be$ AMS research applications.