• Journal of The Korean Association For Science Education
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• v.34 no.7
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• pp.613-624
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• 2014

The aim of this study is to explore why Korean 4th graders' interest in science was not connected to career aspirations in science using the perspective of science identity. Forty-five students with a high interest in science but with low science-related aspirations have been chosen from 488 elementary school students who have completed a questionnaire exploring students' interest and career aspirations in science. Among them, 19 who have received parental permission participated in in-depth interviews examining students' science identities (interest, competence, and recognition by others in science) and their experiences and perceptions of science-related activities. The results showed that most students have limited or situational interest in science, a gap between the perception of their competence in science and their competence for a science-related career, and negative recognition by others in science. Also, participants' science identities and low aspirations for a science-related career constrained their attention and participation in science-related activities. Students' negative science identities and low aspirations for science-related careers were based on the high standards of science-related careers. It seems that these erroneous perceptions and expectations led them to differentiate themselves from students pursuing science-related careers, as well as to perceive that their interest, competence, and recognition by others in science were not enough to pursue a science-related career. This study has implications for understanding the current condition of young students with low aspirations for science careers and exploring desirable objectives and strategies to promote activities to raise their aspirations for science-related careers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.182-187
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• 2013

This study was conducted to examine the effect of calcium extracted from salted anchovy (Engraulis japonicus) on the calcium metabolism of rats. Sprague-Dawley male rats were fed low-calcium diets (0.15%) for 2 weeks after the adjustment period. Rats were divided into five groups and were fed experimental diet for four weeks. Experimental diets were low calcium (LC, 0.15% $CaCO_3$), 0.5% $CaCO_3$ (CC), seaweed calcium (SC), calcium lactate (LC), anchovy calcium (AC). The low-calcium diet group (LC) showed the lowest weight gain and had no differences among the groups with adequate calcium intake. Calcium retention was lowest in the LC group and higher in the CL, SC, AC groups than in SC groups. Serum alkaline phosphatase (ALP) level was highest in LC group, and significantly low in the CC and AC groups (p<0.05). Parathyroid hormone and osteocalcin levels showed no differences among experimental groups. The urine deoxypyridinoline (DPD) level was lower in AC and CC groups compared to the LC group (p<0.05). The dry weight of the femur showed no significant differences among normal calcium groups. The bone mineral density of the femur in AC and CC group were significantly higher than the LC group (p<0.05). From these results, calcium extracted from salted anchovy can be useful as a calcium supplement comparable with calcium carbonate.

• Journal of the Korean Electrochemical Society
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• v.20 no.4
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• pp.67-74
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• 2017

Layered Ni-rich NCM cathode materials $Li[Ni_xCo_{(1-x)/2}Mn_{(1-x)/2}]O_2$ ($x{\geq}0.6$) have advantages of high energy density and cost competitive over $LiCoO_2$. The discharge capacity of NCM increases proportionally to the Ni contents. However, there is a problem that it is difficult to realize the stable electrochemical performance due to cation mixing. In this study, synthesis conditions for the layered Ni-rich NCMs are investigated to achieve deliver the ones having good electrochemical performances. Synthesis parameters are atmosphere, lithium source, synthesis time, synthesis temperature and Li/M (M=transition metal) ratio. The degree of cation mixing gets worse as the Ni content is increased from $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ (NCM6) to $Li[Ni_{0.8}Co_{0.1}Mn_{0.1}]O_2$ (NCM8). It is confirmed that higher level of cation mixing affects negatively on the electrochemical performance of NCMs. Optimum synthesis conditions are explored for NCMx (x=6, 7, 8) in order to reduce the cation mixing. Under optimized conditions for three representative NCMx, a high initial discharge capacity and a good cycle life are obtained for $180mAh{\cdot}g^{-1}$, 96.2% (50 cycle) in NCM6, $187mAh{\cdot}g^{-1}$, 94.7% (50 cycle) in NCM7, and $201mAh{\cdot}g^{-1}$, 92.7% (50 cycle) in NCM8, respectively.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.87-93
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• 2008

Bacillus thuringiensis with selected high toxicities against tobacco cutworm, Spodoptera litura were isolated from domestic soils. When being observed under a phase-contrast microscope, the insecticidal crystal proteins were showed a bipyramidal crystal types. New CAB 109 isolate was identified to B. thuringiensis subsp. aizawai in the H serotype. As a results of insecticidal activities between CAB 109 isolate and 3 existing ready-made products against 3rd larva of S. litura, CAB 109 isolate showed 100% mortality with spore concentration $(1.3{\times}10^7cfu/ml)$. It was a very high insecticidal activity compared with a existing ready-made B. t. products. $LD_{50}$ values of CAB 109 isolate was $9.78{\times}10^5,\;6.87{\times}10^6\;and\;1.83{\times}10^7cfu/ml$ spore concentration against 2nd, 3rd and 4th larva of S. litura, respectively. Unlike Plutella xylostella, S. litura was slowly died after application up to 7 days. The weight of S. litura larva applied with CAB 109 isolate were 6-7 times less than controlled group. Even though it didn't die, it did not grow into next larva. The result observed with scanning electron microscope was that CAB 109 isolate of B. t. aizawai formed a typical bipyramidal crystal protein type. Otherwise, when CAB 109 isolate was examined with SDS-PAGE and with trypsin, there was no difference between CAB 109 strain and ready-made products of B. thuringiensis.

• Journal of the Korean Society for Library and Information Science
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• v.44 no.4
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• pp.333-352
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• 2010

This study analyzed the services of libraries for babies and toddlers and the possibilities of service expansion through Bookstart program as a cooperative system for libraries. This study shows how users change their way of using libraries and their perceptions of the services of libraries for toddlers by implementing the questionnaire method and the analysis of library statistics. Results show that most of library users (98.8%) expressed the need for Bookstart program. Respondes also said that libraries, rather than other institutions, should be the place where the program is to be implemented. By analyzing the perceptions of library users, we also find that they think that the age of the first use of a library is more appropriate for toddlers than kindergarten-ages. We also found that library users who participated in a Bookstart program had a positive change in the way they used libraries. After participating in Bookstart programs, many changes occurred with respect to the perception of babies, reading habits of parents, and users' perception of libraries. After introducing Bookstart program, one city library's membership enrollment rates of babies and toddlers increased from 7.1% to 26.2%. But the rate for another city that did not participate in the program was shown at 4.3%. This study suggests that the introduction of Bookstart program would bring changes and expansions to the functions of libraries and the sometimes inflexible attitudes of library users. The study examined Bookstart program as a cooperative system for libraries by changing the perception of library users and activating the services of libraries for babies and toddlers.

• Clinical and Experimental Reproductive Medicine
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• v.36 no.2
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• pp.121-127
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• 2009

Objective: To investigate the prevalence, the distribution of deciduosis, and the relationship with endometriosis in fertile women during Cesarean delivery. Methods: In this study, pelvic tissues suspicious for ectopic deciduas were taken for biopsy during Cesarean section from 154 parturients of full term pregnancy from January 1990 to December 2003. And then those patients were followed up till April 2008. Results: Tissues from 94 parturients (94/154, 61%) were evaluated histopathologically, and ectopic decidua was observed in 70.2% (66/94). Ectopic sites were ovaries only (65/94, 69.1%), ovaries and uterine serosa (12/94, 12.8%), uterine serosa only (9/94, 9.6%), and pelvic serosa. Twenty seven (27/66, 40.9%) parturients had past history of diagnosis and treatments for endometriosis. We have tried to connect 39 (39/66, 59.1%) patients who had never been diagnosed for endometriosis but pathologically confirmed for deciduosis, and 18 patients were able to contact by phone. Twelve patients (12/18, 66.6%) showed no symptoms of endometriosis and had not received any treatments for endometriosis. Conclusion: We can conclude that most of incidental cases confirmed pathologically for deciduosis during pregnancy do not symptomatically progress.

• Economic and Environmental Geology
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• v.40 no.1 s.182
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• pp.1-14
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• 2007

The Guemseong mine is located near the southern margin of the Jurassic Jecheon granitoids collectively with the Cambro-Ordovician mixed dolostone-limestone series of the Yeongweol Group, Choseon Supergroup. Here, two spatially distinct types of skarn formation have been observed. The upper transitional skarn is the calcic Mo skarn which has the mineral assemblage of $garnet+hedenbergite+epidote{\pm}wollastonite{\pm}magnetite{\pm}hematite{\pm}amphibole{\pm}chlorite{\pm}vesuvianite$ within the calcite marble. On the other hand, the lower proximal skarn occurs as a discordant magnesian Fe skarn at the contact of Mo-bearing aplitic cupolas with unidirectional solidification texture(UST) within the dolomitic marble. The magnesian Fe skarn has the mineral assemlage $olivine+diopside+magnetite+tremolite+serpentine+talc+chlorite{\pm}phlogopite$. The formation of two different types of skarn and ore mineralization in Geumseong mine have been attributed to multistage and complex metasomatic replacements that ultimately resulted in silicate-oxide-sulfide sequence of metasomatism. An early prograde stage with anhydrous skarn minerals such as olivine, clinopyroxene and/or garnet with magnetite, formed from high temperature (about $500^{\circ}\;to\;400^{\circ}C$) at an environmental condition of low $CO_2$ fugacity ($XCO_2<0.1$) and 0.5 kbar. The later retrograde stage with hydrous silicates such as amphibole, serpentine, phlogopite, epidote and chlorite with molybdenite or hematite, termed from relatively lower temperature (about $400^{\circ}\;to\;300^{\circ}C$).

• Horticultural Science & Technology
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• v.30 no.5
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• pp.543-548
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• 2012

Morphological characters of Baemoochae, xBrassicoraphanus are mostly intermedium of the both parents, Chinese cabbage, Brassica rapa ssp. pekinensis and radish, Raphanus sativus. The upper and lower parts of the leaf resemble the shape of Chinese cabbage and radish, respectively. The midrib of the leaf is round like to that of radish, but very big more than 3 cm in diameter and white in color like that of Chinese cabbage. The root was changed from the swollen type like that of radish to the enlarged taproot like that of the land race of Chinese cabbage after attaining genetical stability. The flower is white. The seed pod is divided into 2 different parts; the upper part is radish and about 4 cm in length and holds 3-4 seeds and the lower part is Chinese cabbage and about 3 cm in length and holds 7-8 seeds. The color of seed is brown, weight per 1.000 seeds is 5.5 g and the number of seeds per mL is 120. The matured plant in the fall season is around 5 kg in weight and outer leaves are very vigorous and stiffly and inner leaves are erect and form a loose head. The leaf and the root contain a high level of sulforaphene which is well known as a functional substance for anti-cancer and anti-super-bacteria. Baemoochae is an amphidiploid and does not have the self incompatibility function. It has a high level of cross compatibility with Chinese cabbage as the female parent, but not the male parent. It is cross incompatible to cabbage, B. oleracea, black mustard, B. nigra and radish. However it is highly compatible to oil seed rape, B. napus, yellow mustard, B. carinata and partial compatible to muatard, B. juncea in the reciprocal cross.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.509-518
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• 2012

The objective of this study was to determine the effect of heat shock treatments on the phytochemicals including antioxidants and anticancer materials in kale (Brassica oleracea L. var. acephala) sprouts. In study I, kale sprouts grown under the growing system for four days were soaked at 40, 50, or $60^{\circ}C$ distilled water for 10, 30, or 60 seconds, and in study II, kale sprouts were soaked at $50^{\circ}C$ distilled water for 10, 20, 30, 45, or 60 seconds. After the heat shock treatments, the sprouts were transferred into normal growing conditions and recovered there for two days. Fresh and dry weights, electrolyte leakage, total phenolic concentration, antioxidant capacity, total flavonoid concentration, phenylalanine ammonia-lyase (PAL) activity, and glucosinolates content of the sprouts were measured before and after the heat shock treatments. As a result, there was a significant decrease in the fresh and dry weight of kale sprouts treated with heat shock compared with control at harvest in study I. Especially, heat shock at $60^{\circ}C$ lead to more pronounced growth inhibition compared with heat treatments at 40 and $50^{\circ}C$. Electrolyte leakage by cell collapse was the highest in the sprouts exposed to $60^{\circ}C$ distilled water, which agreed with the growth results. Heat shock at $50^{\circ}C$ significantly induced the accumulation of phenolic compounds. In study II, fresh weight of kale sprouts at $50^{\circ}C$ heat shock showed a significant decrease compared with the control at one and two days after the treatment. However, the decrease was minimal and dry weight of kale sprouts was not significantly different from that in control. In contrast, the heat shock-treated kale sprouts had higher level of total phenolic concentration than control at harvest. Heat shock treatments at $50^{\circ}C$ for 20 seconds or more showed at least 1.5 and 1.2 times higher total phenolic concentration and antioxidants capacity than control, respectively. The change of the total flavonoid concentration was similar with that of antioxidants. PAL activity after 24 hours of heat shock was higher in all the heat shock-treated sprouts than that in control suggesting heat shock may stimulate secondary metabolic pathway in kale sprouts. Seven glucosinolates were identified in kale sprouts and soaking the sprouts with $50^{\circ}C$ water for 20 seconds had a pronounced impact on the accumulation of total glucosinolates as well as two major glucosinolates, progoitrin and sinigrin, at harvest. In conclusion, this study suggests that heat shock using hot water would be a potential strategy to improve nutritional quality of kale sprouts by inducing the accumulation of phytochemicals with antioxidant and anticancer properties.

• Journal of Oriental Neuropsychiatry
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• v.15 no.2
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• pp.149-158
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• 2004

만성적이거나 반복적인 스트레스는 우울중이나 심신병 등의 발병 기전과 밀접한 관련이 있다. 전기적 자극(electric foot shock), 한랭 자극, 속박(immobilization), 투쟁(fighting), 에테르 노출 등과 같은 심한 스트레스 자극이 뇌 조직의 시상 및 시상하부, 편도체 등에서의 노르아드레날린(noradrenalin) 방출을 유의 하게 감소시키는 동시에 혈청 corticosterone을 증가시키는 것으로 알려져 있다. 한의학에서는 스트레스 인자에 대한 신체반응을 기(氣)의 변화로 인식하고 있고, 이러한 자극요인들은 신체에 대하여 병적 요인을 제공하여 제반 질환을 야기한다. 또한 질병 발생에 대한 근거로 정기(正氣)와 사기(邪氣)의 상호 관계 위주로 인식하는데, 내부의 기(氣)의 변조(變調)는 질병의 발생을 야기하는 기초가 된다. 실험에 사용된 연근(蓮根)은 연꽃과에 속한 수생초본인 연꽃의 뿌리부분으로 우(藕) 또는 우절(藕節)이라는 명칭으로 불리기도 한다. 성미(性味)는 감(甘) 삽(澁) 평(平) 무독(無毒)하고 폐(肺) 위(胃) 간경(肝經)으로 들어가며 수렴지혈(收斂止血) 화어(化瘀)의 효능이 있어 토혈(吐血) 객혈(喀血) 뇨혈(尿血) 편혈(便血) 등의 각종 출혈 증상에 사용되어져 왔다. 최근 연꽃의 부위별 추출물이 흰쥐의 지질 과산화 생성을 효과적으로 억제하는 것으로 보고되고 있어 연근(蓮根)에 대한 다양한 약리 효능의 검색이 필요할 것으로 생각되며 연꽃의 씨앗인 연자육(蓮子肉)이 양심안신(養心安神)의 효능이 있어 스트레스성 질환에 많이 응용되고 있는 것에 착안하여 본 연구를 착수하였다. 실험 동물은 ICR계 마우스를 이용하였으며, 사회 심리적 스트레스는 옆쪽 cage에서 다른 마우스의 신체에 가해지는 전기 충격을 하루 1시간 동안 지켜보게 하는 것으로 유발하였으며 이 상태에서 약물을 투여한 그룹을 실험군, 그렇지 않은 그룹을 대조군으로 하였다. 정상군은 아무런 자극 없이 하루 1시간 동안 일정 공간에 가두어 두는 것으로 하였다. 실험 결과 사회 심리적 스트레스를 받은 경우에 아무런 처치를 하지 않은 대조군에 비해 연근 추출물을 100mg/kg/day 용량으로 5 일간 투여한 실험군에서 혈청 중 corticosterone 함량이 유의하게 감소하였으므로 매우 효과적으로 스트레스를 해소하였음을 알 수 있다. 뇌세포 중에서 신경전달물질로 분비되는 노르아드레날린의 분비량은 전반적으로 증가되는 경향을 나타내었으나 유의성은 없었다. 신체적 또는 사회 심리적 스트레스가 간 조직 내 지질의 과산화를 유발하는 것으로 나타났으며 연근 추출물이 이 결과에는 영향을 주지 못하였다. 사회 심리적 스트레스로 인하여 간 조직 내 지질과산화 정도가 증가하였으므로 혈청 내 ALT 함량도 따라 증가할 것으로 추정되었으며 이에 대한 연근 추출물 경구 투여가 간 조직을 보호할 수 있는지를 확인하기 위해 분리한 혈청으로부터 ALT 함량을 측정한 결과 대조군에 비하여 유의한 감소를 나타내었다. 또한 연근 추출물이 혈청 내 지질 과산화물의 생성을 억제할 수 있다면 질병의 예방과 치료에 효과적일 것으로 추정할 수 있으므로 그 생성량을 측정하여 보았으나 대조군과의 차이가 나타나지 않았다. 이상의 결과들을 종합하여 보면 스트레스가 부하된 5일 동안 연근(蓮根) 추출물을 함께 투여한 결과 혈청 corticosterone 함량을 유의하게 감소시켰고 뇌 조직내 noradrenaline 함량을 증가시키는 경향을 나타내어 스트레스 해소에 도움이 될 수 있음을 시사하였다. 또한 혈청 내 ALT 함량을 유의하게 감소시켜 스트레스로 인해 발생하는 간 기능의 손상도 어느 정도 억제시키는 것을 확인할 수 있었는데 앞으로 연근(蓮根)의 이러한 작용에 대한 보다 자세한 연구들이 필요한 것으로 생각된다.