• Journal of Astronomy and Space Sciences
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• 제14권1호
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• pp.94-108
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• 1997

열권 상부의 온도는 일반적으로 태양 활동에 따라 변화하며, 특히 고위도 지역에서는 지자기 활동에 의해서도 크게 변화된다. 본 연구에서는 장기간에 걸쳐 관측된 열권 온도를 이용하여 태양 활동 지수 및 지자기 활동 지수와의 상관 관계를 정량적으로 분석하였다. 본 연구에서 사용된 온도 자료는 미시간 대학에서 운용하고 있는 그린랜드의 두 관측소인 Thule Air Base(76.6$^{\circ}$N, 68.4$^{\circ}$W, Λ = 86$^{\circ}$)와 Strømfjord (67.0$^{\circ}$N,50.9$^{\circ}$W, Λ - 74$^{\circ}$)에서 측정된 것으로 두 곳 모두 지리적 뿐만 아니라 지자기적으로도 고위도 지역에 위치하고 있다. 자료는 페브리-페로 간섭계를 이용하여 6300 $\AA$ 대기광을 관측한 것이며 관측기간은 Thule Air Base 관측소는 1986~1991년, Søndre Strømfjord 관측소는 1986~1994년이다. 본 연구에서 얻어진 분석 결과는 다음과 같다. (1)Thule 지역의 관측 온도와 태양 활동 지수와의 상관 관계는 3$\leq$Kp$\leq$4에서 가장 높게 나타나며 Søndre Strøfjord 지역의 상관 관계는 Kp 지수가 커질수록 증가함을 보인다. (2) 전반적인 온도는 고위도 지역인 Thule 지역에서 높지만, 태양 활동 지수 변화에 따른 온도 변화의 증가율은 Søndre Strømfjord 지역에서 더 크게 나타났다. (3) 겨울철 Thule 지역의 하루 온도 변화는 13-14 LT(LT=UT-4) 부근에 최대 온도를 가진 일일 주기(24hrs) 변화를 보이지만, 태양 활동이 미약한 경우에는 반일 주기 (12 hrs) 변화가 우세하게 나타났다. (4) 고층 대기분야에서 통용되는 MSIS86 모델과 VSH 모델은 여기서 분석된 관측치에 비해 전반적으로 낮은 온도를 예측하고 있으며, 이러한 차이는 특히 태양 활동이 증가함에 따라 더욱 심해짐을 보였다. 따라서 보다 많은 관측 자료를 이용한 새로운 열권 모델의 개발이 시급하다고 생각된다.

• 한국해양공학회지
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• 제14권2호
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• pp.99-105
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• 2000

This paper describes the effect of specimen size on fatigue crack growth rate for the offshore structural high-tensile-strength steel BS4360 and machine structural steel SM45C. The purpose of the present study is to investigate the effect of stress ratio aspect ratio specimen width and specimen thickness of the fatigue crack growth behavior. Compact tension specimens with a LT orientation for BS4360 and SM45C steels were used, All testing was done at constant stress intensity factor range controlled fatigue crack growth condition. The investigation demonstrates that the fatigue crack growth rate is increased with increasing stress ratio and specimen thickness and is decreased with increasing specimen width. The fatigue crack growth rate is unaffected by aspect ratio until a/W=0.50 but is increased by increasing spect ratio from a/W=0.55.

• 핵의학기술
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• 제27권1호
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• pp.7-8
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• 2023

A 50-year-old female patient referred by the department of breast and thyroid surgery was recommended for orthopedic surgery because lesion like herniation pit was found in the left proximal femur in bone mineral densitometry (BMD). She was later diagnosed with bone metastasis on biopsy in orthopedic surgery. Pelvic X-ray and Lt thigh MRI were performed . Intra-medually nail was operated later. The BMD is a diagnostic method that determines the results by numerical values, so it is inevitable to neglect to observe the bone shape, but as shown in the above case, the examiner's observation of changes in bone shape can return to beneficial treatment for patients.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.820-829
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• 2003

One of the important function of skin is the protection from harmful environments. Many studies were carried out to keep the skin from wrinkling and pigmenting. Skin wrinkle and pigmentation could be caused' by the unusual disruption of connective tissue, the formation of free radicals and the radiation of ultraviolet. In this study, the extracts obtained from 23 different kinds of medicinal plants were examined whether they have inhibitory effect on tyrosinase and elastase as well as free radical scavenging effect. All the extracts examined were obtained by using 70% (v/v) ethanol at $60^{\circ}C$. It has been found that there were two medicinal plants which have positive effects matching with the purpose of this study. The extract of Ephedra sinica stapf shows an inhibitory effect on tyrosinase ($IC_{50}$ = 83.7~$\mu\textrm{g}$/ml), on elastase ($IC_{50}$ = $690{\mu}\textrm{g}$/ml), and also shows free radical scavenging effect ($IC_{50}$ = 29.6$\mu\textrm{g}$/ml). The extract of Betula platyphylla Var. shows an inhibitory effect on elastase ($IC_{50}$ = 498.1$\mu\textrm{g}$/ml), and free radical scavenging effect ($IC_{50}$ = 9$\mu\textrm{g}$/ ml). The aim of the study is to find the natural compounds which have function in skin-lightening, anti-wrinkling and anti-oxidation, with safe and active ingredients in cosmetic.

• 대한한방체열의학회지
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• 제2권1호
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• pp.35-42
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• 2003

Objective : This study is to examine the interrelationship between Infertility with hypothalamic-pituitary gland disorders and Face temperature by D.I.T.I. Methods : Sample group is the 50 women who were diagnosed as P.C.O.S. or FSH,LH trouble or hyper-prolactinemia or anovulation or oligo-ovulation. Control group is the 50 women who have not P.C.O.S. & FSH.LH trouble & hyper-prolactinemia & anovulation or oligo-ovulation, who have normal menstural cycle and success in pregnancy after treatment. Both group came at Conmaul Oriental Hospital Infertility Center, Seoul, Korea, from May, 2001 to Jan., 2003. They selected at random. We checked temperature of ${\ulcorner}S17{\lrcorner}\;{\ulcorner}SI18{\lrcorner}\;{\ulcorner}TE17{\lrcorner}\;{\ulcorner}HN-3{\lrcorner}$ and gained differences of Rt. check point and Lt. check point, and then compared mean ${\Delta}T$ of sample group with that of control group. Conclusion : We gained results that mean ${\Delta}T$ of sample group is larger than that of control group at all check points. (p=0.000)

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.706-709
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• 2003

Ginsenosides and polysaccharides were isolated from Panax ginseng C.A. Meyer (Family Araliaceae) by treating at low ($60^{\circ}C$, LT), mild ($100^{\circ}C$, MT), and high ($120^{\circ}C$, HT) temperatures, and their inhibitory effects on growth, infection, and VacA vacuolation of Helicobacter pylori (HP) were investigated. The molecular weights of polysaccharides decreased as the processing temperature increased. Ginseng polysaccharides inhibited the HP infection into KATO III cells, but did not inhibit growth of HP and VacA vacuolation of HeLa cells. HT polysaccharides showed the most potent inhibition with $IC_50$ value of 6.8 mg/ml. Ginseng saponins did not inhibit the infection of HP into KATO cells. However, 20(s)-protopanaxadiol showed the most potent inhibition of HP growth and vacuolation of HeLa by VacA toxin with $IC_50$ values of 0.05 and 0.067 mg/ml, respectively.

• 한국작물학회지
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• 제50권2호
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• pp.67-72
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• 2005

Overwintering capacity, closely related to winter hardiness, of Chinese milk vetch planted with different sowing times and sowing practices was investigated to improve the incorporation into cropping system in Korea. The tolerance to low temperature was evaluated with $LT_50$ using leaf disc leaching method. Dry weight of CMV was reduced remarkably with delayed planting from Sep. 5 to Oct. 20. The differences in tolerance to freezing temperature were not conspicuous among CMV genotypes, however, the differences between genotype (collections at different regions) were due to the plant architecture, mainly to the leaf angle. The crouching genotype collected at central region of Korean peninsula, which showed excellent freezing tolerant, has planophile leaves. The feature of internal constituents of CMV genotypes did not show any noticeable differences with respect to the freezing tolerance which evaluated by leaf disc leaching experiment. To overcome the poor overwintering capacity, tolerant genotype should be developed by selection with considering the plant architecture. The reduction of CMV growth during overwintering period was ameliorated with furrow-sowing under late-sown condition, therefore, when the CMV is inevitably sown late after recommended time, the seeds should be sown on furrow to overcome the cold stress.

• 생약학회지
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• 제44권3호
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• pp.305-311
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• 2013

Advanced glycation end products (AGEs) have been postulated to play a central role in the development of diabetic complications. A variety of different agents that inhibit AGEs have been under investigation. In this study, 54 herbal medicines from China have been investigated with an in vitro evaluation system using AGEs formation inhibitory activity. Of these, 6 herbal medicines ($IC_{50}<5{\mu}g/ml$) were found to have significant AGEs formation inhibitory activity. Particularly, herbal medicines Punica granatum (peels), Terminalia chebula (fruits), Rheum palmatum (roots), Oxyria digyna (stems and leaves), Anisodus luridus (roots) and Quercus schottkyana(stems and leaves) showed more potent inhibitory activity (approximately 9-43 fold) than the positive control aminoguanidine ($IC_{50}=77.04{\mu}g/ml$).

• Mycobiology
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• 제46권4호
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• pp.440-447
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• 2018

Dual biocontrol of both insects and plant pathogens has been reported for certain fungal entomopathogens, including Beauveria bassiana and Lecanicillum spp. In this study, we demonstrate, for the first time, the dual biocontrol potential of two fungal isolates identified by morphological and phylogenetic analyses as Isaria javanica. Both these isolates caused mortality in the greater wax moth, and hence can be considered entomopathogens. Spores of the isolates were also pathogenic to nymphs of the green peach aphid (Myzus persicae), with an $LC_{50}$ value of $10^7spores/mL$ 4 days after inoculation and an $LT_{50}$ of 4.2 days with a dose of $10^8spores/mL$. In vitro antifungal assays also demonstrated a strong inhibitory effect on the growth of two fungi that are pathogenic to peppers, Colletotrichum gloeosporioides and Phytophthora capsici. These results indicate that I. javanica isolates could be used as novel biocontrol agents for the simultaneous control of aphids and fungal diseases, such as anthracnose and Phytophthora blight, in an integrated pest management framework for red pepper.

• Journal of Microbiology and Biotechnology
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• 제26권6호
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• pp.1026-1034
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• 2016

In the current study, a total of 135 enterococci strains from different sources were screened for the presence of the enterocin-encoding genes entA, entP, entB, entL50A, and entL50B. The enterocin genes were present at different frequencies, with entA occurring the most frequently, followed by entP and entB; entL50A and L50B were not detected. The occurrence of single enterocin genes was higher than the occurrence of multiple enterocin gene combinations. The 80 isolates that harbor at least one enterocin-encoding gene (denoted "Gene⁺ strains") were screened for antimicrobial activity. A total of 82.5% of the Gene⁺ strains inhibited at least one of the indicator strains, and the isolates harboring multiple enterocin-encoding genes inhibited a larger number of indicator strains than isolates harboring a single gene. The indicator strains that exhibited growth inhibition included Listeria innocua strain CLIP 12612 (ATCC BAA-680), Listeria monocytogenes strain CDC 4555, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, S. aureus ATCC 29213, S. aureus ATCC 6538, Salmonella enteritidis ATCC 13076, Salmonella typhimurium strain UK-1 (ATCC 68169), and Escherichia coli BAC 49LT ETEC. Inhibition due to either bacteriophage lysis or cytolysin activity was excluded. The growth inhibition of antilisterial Gene⁺ strains was further tested under different culture conditions. Among the culture media formulations, the MRS agar medium supplemented with 2% (w/v) yeast extract was the best solidified medium for enterocin production. Our findings extend the current knowledge of enterocin-producing enterococci, which may have potential applications as biopreservatives in the food industry due to their capability of controlling food spoilage pathogens.