• Journal of The Korean Association For Science Education
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• v.34 no.5
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• pp.491-497
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• 2014

The purpose of this study is to investigate the structural relationships among the attitude toward science and science motivation such as affective characteristics, and self-regulated learning strategy such as cognitive factor of science achievement. 853 middle school students residing in Seoul completed questionnaires about attitude toward science, science motivation, and self-regulated learning strategy. The sample variance-covariance matrix was analysed using AMOS 20.0, and a maximum likelihood minimization function. The results are as follows: First, attitude toward science, science motivation and self-regulated learning strategy of middle school students were all found to have a significant direct effect on science achievement. Second, attitude toward science and science motivation in middle school students has a direct effect on the self-regulated learning strategy. Third, attitude toward science in middle school students has a substantial indirect effect on science achievement mediated by their self-regulated learning strategy. Forth, science motivation in middle school students has indirect effect on science achievement mediated by their self-regulated learning strategy. Therefore, in order to improve science achievement among middle school students, teachers should consider synthetically the affective characteristics such as attitude toward science and science motivation, and cognitive factor such as self-regulated learning strategy.

• Biomedical Science Letters
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• v.1 no.1
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• pp.45-54
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• 1995

The effect of different fatty acids supplementation on antobody production of Salmonella typhi was studied in ICR mice. Subjects supplemented their diets with $50\mu$g of extracted pig oil(as a saturated fatty acid) and fish oil (as a unsaturated fatty acid) / 2 days for 8 weeks. Blood was collected control and experimental groups of mice after 8 weeks of oil supplementation. The different fatty acids supplementation reduced unsaturated fatty acids composition in mice liver such as $C_{18:3}, \; C_{20:3}\; and\; C_{20:4}\; except\; C_{18:1}\; and\; C_{18:2}/C_{18:0}$ in fish oil and pig oil groups compared to control group. Also, the phagocytic activities of mice macrophages for Candida albicans was reduced by 6% in pig oil group and 9％ in fish oil group than control group. The antigen-stmulated lympocite proliferative response was significantly increased by fatty acid in pig oil group(48％) but 57％ in fish oil group. The different fatty acid supplementation increased antibody production in both experimental groups than control group ; this increase was only significant in pig oil group(1:$2^4$) on mice but not in fish oil group(1:$2^0$) compared to control group(1:$2^0$), however, increased antibody titer in both groups in vitro spleen cell culture supernatant(1:$2^3$ in fish oil group and 1:$2^2$ in pig oil group compared to control group 1:$2^0$). Thus, fish oil supplementation was immunosuppresive agent in macrophage phagocytosis, in-vivo antobody producibilities and lympocyte proliferation but pig oil supplementation was more effective than fish oil in antibody formation in-vivo. We find that antibody producibilities affected by fed on different fatty acids were considered by balance between saturated and unsaturated fatty acid, and $C_{20:3}/C_{20:4}$ ratio. Also, it affected to antigen-stimulated lymphocyte proliferation and macrophage phagocytic activities.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.3
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• pp.203-208
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• 2007

The woody tissue respiration rates in stems ($R_{stem}$) of red pine (Pinus densiflora Sieb. et Zucc.) forest in Higashi-Hiroshima, west Japan, were measured using an open flow measurement system with several chambers in two seasons (the winter and summer in 2002). $R_{stem}$ ranged from 0.25 to $0.55{\mu}mol\;m^{-2}s^{-1}$ in winter, and from 1.25 to $1.63{\mu}mol\;m^{-2}s^{-1}$ in summer. The variability of $R_{stem}$ among the sampled trees (n=15) was similar between the two seasons, with the coefficient variation of about 23%. The numbers of sampling points required to estimate the stem respiration rate within 10 to 20% of its actual value were 24 and 6, respectively in both seasons (probability level is 95%). Based on the relationship between stem temperature and average $R_{stem}$ the $Q_{10}$ values of the winter and summer seasons were 1.49 and 1.45, respectively. The $R_{20}$($R_{stem}$ at $20^{\circ}C$ of stem temperature) was higher in summer ($1.23{\mu}mol\;m^{-2}s^{-1}$) than winter ($0.61{\mu}mol\;m^{-2}s^{-1}$). The woody tissue respiration in stems of red pine trees during the summer season amounted about 50% of the total respiration rates.

• The Korean Journal of Malacology
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• v.30 no.3
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• pp.243-248
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• 2014

This study histologically describes the gonadal development and reproductive cycle of the abalone, Haliotis discus hannai inhabiting Jindo on the southern seashores of Korea. Gonads displayed histologically definitive seasonal changes. The female ratio (F/F + M) was 57% (n = 154/271). The gonad index (GI) of both males and females was the highest (3.3 and 3.9) in June and was the lowest (1.1 and 1.1) in December. The condition index (CI) and meat weight rate (MWR) were highest in May and lowest in October. The pattern of changes in the GI, CI and MWR were similar to the pattern of seasonal changes in gonadal tissues. The reproductive cycle was divided into an inactive stage (November-December), early active stage (January-March), late active stage (March-April), ripe stage (May-June) and spent and degenerative stage (July-October). The main spawning period of Haliotis discus hannai was July to August at Jindo in 2013.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.542-550
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• 2016

This study analyzed the direct and indirect effects of job competency education on job goal setting, job preparation behavior and first job satisfaction from the perspective that successful employment requires improving the job ability needed for college students. Data on 5,044 students were analyzed based on the 2013GOMS of Graduates Occupational Mobility Survey(GOMS). The study findings are summarized as follows. First, job competency education not only acted positively on job goal setting but also contributed to promoting job preparation behavior. Second, job preparation behavior contributed to improving satisfaction with the first job. Third, indirect effects of job competency education and job goal setting in first job satisfaction. In conclusion, job competencies enhances the possibility that college students may obtain their wanted job by setting a clear goal for their job and having a positive effect on the required behavior. Accordingly, college student should try to reinforce their special capability to accomplish the given job as career professionals in consideration of their aptitude rather than devoting themselves to reinforcing their basic capability such as linguistic ability. For this purpose, both universities and the government should develop educational programs for college students to grasp their aptitude and cultivate their special ability to become career professionals and provide a foundation for them to become talented professionals armed with special capability by proving support for job ability improvement.

• Korean Journal of Materials Research
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• v.2 no.6
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• pp.389-397
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• 1992

Workability and aging behavior of Mg-Li-Al alloys hate been investigated with variation of Li and Al contents. It was found that ${\alpha}$(HCP) + ${\beta}$(BCC) two phase structure reveals better workability than ${\alpha}$(HCP) single phase structure. Increase of workability is attributed to the additional slip on pyramidal and prism planes besides the slip on basal plane of HCP Mg. Workability of ${\alpha}$+${\beta}$ two phase structure is improved with increased amount of Al. Among alloys studied in the present study, reduction limit up to 62 % was obtained for Mg-8.08Li-4.26Al. MgL$i_2$Al(${\theta}$) aging precipitation was observed in ${\alpha}$+ ${\beta}$ two phase structure, while it was not in a single phase structure. Result of microhardness reveals peak hardness for ${\alpha}$ +${\beta}$ two phase structure due to $\theta$ precipitate in ${\theta}$ phase. In ${\alpha}$+${\beta}$ two phase Mg-Li-Al alloys, hardness increased with increasing amount of Al. It is believed that addition of Al raised the amount Al partition in u phase and ${\theta}$ precipitation in ${\beta}$ phase.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.313-318
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• 2008

Dens invaginatus is a rare malformation resulting from invagination of the enamel before calcification has occurred. It is mostly found in permanent maxillary lateral incisors and mandibular teeth are rarely affected by this anomaly. The malformation is estimated to affect between 0.04 % and 10 % of people and has been associated with other abnormalities such as taurodontism, microdontia, gemination and dentinogenesis imperfecta. Dens invaginatus is classified in three types with respect to the depth of invaginatus and has a broad spectrum of morphologic variations. Invagination frequently allows the entry of irritants and microorganism, which usually lead to caries, pulp infection and pulp necrosis. Root canal treatment on such invaginatus tooth may present severe problems because of its complex anatomy of the tooth. Therefore, the early diagnosis of such malformation is crucial and preventive approach is strongly recommended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.318-322
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• 2014

5-Alpha reductase II, which converts testosterone (T) to dihydrotestosterone (DHT), is a crucial enzyme II in benign prostatic hyperplasia. Inhibitory effects of Curcuma longa L. (CL) extracts on 5-alpha reductase II activity were investigated in rat prostate tissue homogenates as well as LNCaP cells expressing human 5-alpha reductase II. Hot water extract (CL-HW) of Curcuma longa L. significantly inhibited 5-alpha reductase activity by over 80% at a concentration of $100{\mu}g/mL$, whereas 20% ethanol extracts (CL-E20) of Curcuma longa L. exhibited significant inhibitory activity from $50{\mu}g/mL$. These results indicated that Curcuma longa L is a potent 5-alpha reductase II inhibitor for benign prostatic hyperplasia treatment.

• Journal of Korean Society of Forest Science
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• v.82 no.4
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• pp.337-346
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• 1993

Experiments were performed to find out the effects of simulated acid rain(SAR) of pH 4.0 or pH 2.5 for 12 weeks on stomatal resistance, wettability and anatomical changes in Quercus acutissima and Ginkgo biloba seedlings. As a control, distilled water with a pH 6.5 was also sprayed. Stomatal resistance of Q. acutissima and of G. biloba remarkably increased after exposure to SAR. SAR increased the wettability of Q. acutissima leaves measured with water blue solution and of G. biloba leaves measured by leaf contact angle method. Anatomical changes in the leaves of Q. acutissima affected by SAR were the partial damage of epidermis and parenchymatous cells. Scanning electron microscopical observation showed that the number of trichomes in the leaves of Q. acutissima treated with SAR markedly decreased and the erosion of epicuticular wax was significant. No distinct damage was found in the G. biloba leaves at pH 4.0, while epidermis and vascular tissue were collapsed at pH 2.5. No significant alteration of surface structures in this tree species was observed.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.55.2-55
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• 1998

다견정 심리판-거l르마늄(JXlly-SiGe)은 TFT(thin-film transistor)와 갇븐 소자 응용에 있어서 중요한 불칠이다 .. LPCVD (low pressure chemical vapor deposition) 방법으로 비정칠 SiGc (a-SiGe) 박막올 증 착시키고 고상결정화(SPC: solid-phase crystallization)시켜 poly-SiGc옹 얻는 것은 잘 알려져 있다. 그러 나 그러나 PF'||'&'||'pound;VD-SPC 방법올 이용한 poly-SiGc의 제조에 대해서는 아직 두드러지게 연구된 바 없다. 우리단 PF'||'&'||'pound;VD 방법으로 a-SiGc 박막올 증착시키고 고상캘정화시켜 poly-SiGc올 얻었 R며, :~ 결정성, G Gc 농도, 결정핍의 평끌 크기 눔올 XRD (x-ray diffraction) 방법으호 조사하였다. 특히 pr'||'&'||'pound;VD 증착시 가판온도,Gc 함유량 등이 고상화에 미치는 영향에 대해서 조사하였다. P PECVD 장치는 터보펌프콸 사용하여 71저진공이 2xlOlongleftarrow5 Torr에 이르렀다. 가판윤 SiOOO) 웨이퍼륜 사용하고 기판 온도는 약 150- 35()"C 사이에서 변화되었다. 증착가스는 SiH4, GcH4, 112 등흘 썼다. 증착 압력과 r.f 전력용 각각 O.25ToIT와 3W로 일정하게 하였다 .. Gc 함유량(x)은 x x=O.O-O.5 사이에서 변화되었다 .. PECVD모 증착된 SiGc 박막들은 고상결정화를 위해 $\theta$X)"(:: Nz 분위기에서 24시간동안, 혹은 5OO'C에서 4열간 가열되었다. 고상결정화 후 poly-SiGc 박막은 SiGc(Ill), (220), (311) XRD 피크들올 보여주었으며, 각 피 크들은 poly-Si에 비하여 왼쪽으로 Bragg 각이 이동되었고, Vegard’slaw에 의해서 x의 값올 확 인할 수 있었다. 이것온 RBS 결과와 열치하였다. 약 150-350'C 사이에서 변화된 기판온도의 범위 에서 증착온도가 낮올수콕 견정립의 크기는 대체로 증가하는 것으로 나타났다 .. XHD로 추정된 형 균 결정립의 크기는 최대 약 3$\alpha$1m 정도였다. 또한 같끈 샘플뜰에 대해서 기판온도가 낮올수록 증착속도가 증가함옴 확인하였다 .. Gc 함유량이 x=O.1에서 x=O.5로 증가함에 따라서도 결정립의 크기와 SiGc 증착속도는 증가하는 것으로 나타났다 .. Hwang [1] , Kim[2] 둥의 연구자들은 Gc 함유 량이 증가함에 따라 결정 립 크기가 캄소하는 것올 보고하였으냐, Tsai [3] 둥은 반대의 결과플 보 고하고 Ge 힘유량의 증가시 결정립 크기의 증가에 대해 Gc의 Si보다 낮은 융점 (melting point) 올 강조한 바 있다. 결정립 크기의 증가는 대체로 SiGe 중착속도의 증가와도 관련이 있음올 볼 때, poly-SiGc의 경우에도 polv-Si의 고상화에서와 같이 증착속도가 빠를수록 최종적언 결정럽의 크기가 커지는 것으로 이해될 수도 있다 .. PECVD 증착시 증착속도의 증가는 증착된 박딱에서의 무켈서도를 증 가시킬 수 있음올 고려하면, 이라한 결파플온 p이y-SiGc의 고상결정화에서도 ploy-Si의 고상결정 화에서와 마찬가지로 초기 박막에서의 구조직 무절서도가 클수록, 고상결정화 후 결정 립의 크기 가 커칠 수 있음올 보여준다고 생각휠 수 있다,