• Title/Summary/Keyword: Lee Sam

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The Novel Biological Action of Antimicrobial Peptides via Apoptosis Induction

  • Cho, Jaeyong;Hwang, In-Sok;Choi, Hyemin;Hwang, Ji Hong;Hwang, Jae-Sam;Lee, Dong Gun
    • Journal of Microbiology and Biotechnology
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    • v.22 no.11
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    • pp.1457-1466
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    • 2012
  • Antimicrobial peptides (AMPs) exert antimicrobial activity against Gram-positive and Gram-negative bacteria, fungi, and viruses by various mechanisms. AMPs commonly possess particular characteristics by harboring cationic and amphipathic structures and binding to cell membranes, resulting in the leakage of essential cell contents by forming pores or disturbing lipid organization. These membrane disruptive mechanisms of AMPs are possible to explain according to the various structure forming pores in the membrane. Some AMPs inhibit DNA and/or RNA synthesis as well as apoptosis induction by reactive oxygen species (ROS) accumulation and mitochondrial dysfunction. Specifically, mitochondria play a major role in the apoptotic pathway. During apoptosis induced by AMPs, cells undergo cytochrome c release, caspase activation, phosphatidylserine externalization, plasma or mitochondrial membrane depolarization, DNA and nuclei damage, cell shrinkage, apoptotic body formation, and membrane blebbing. Even AMPs, which have been reported to exert membrane-active mechanisms, induce apoptosis in yeast. These phenomena were also discovered in tumor cells treated with AMPs. The apoptosis mechanism of AMPs is available for various therapeutics such as antibiotics for antibiotic-resistant pathogens that resist to the membrane active mechanism, and antitumor agents with selectivity to tumor cells.

Correlations Between Pore Structure of Activated Carbon and Adsorption Characteristics of Acetone Vapor (활성탄의 세공구조와 Acetone Vapor 흡착특성의 상관관계)

  • Lee, Song-Woo;Bae, Sang-Kyu;Kwon, Jun-Ho;Na, Young-Soo;An, Chang-Doeuk;Yoon, Young-Sam;Song, Seung-Koo
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.6
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    • pp.620-625
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    • 2005
  • This study is to investigate the correlation between pore structures of activated carbons and adsorption characteristics of acetone vapor using the dynamic adsorption method. The experimental results showed that the breakthrough time of ACT activated carbon made by Takeda was the longest, because ACT has more micropores below pore diametr $10{\AA}$ than the compared activated carbons. The equilibrium adsorption capacity had direct correlation to the breakthrough time. The relation between BET specific surface area and the equilibrium adsorption capacity was hard to say linear. Therefore, it was difficult to estimate the adsorption ability of activated carbons only by BET specific surface area. The correlation factor between the cumulative surface area and the equilibrium adsorption capacity decreased with enlarging the range of pore size, and there was the highest correlation factor in the range of below $10{\AA}$.

Earthquake Resistant Design Methods on the Slopes (지진을 고려한 비탈면 설계 방안)

  • Kim, Ju-Hyong;Lee, Yong-Su;Cho, Sam-Deok
    • Journal of the Korean Society of Hazard Mitigation
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    • v.5 no.1 s.16
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    • pp.23-32
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    • 2005
  • A significant development has been made on earthquake resistant designs on many structures since the Korean government has begun modern earthquake hazard reduction programs after recognizing potential disastrous consequences of seismic events following the Kobe earthquake in 1995. However, some structures such as slope structures still haven't get ready for their own seismic design guidelines in Korea. Therefore, only a few organizations of Korea adopt seismic design for slopes relying on designers' judgments at present. This paper introduces domestic and foreign research activities on seismic slope stability and an idea of Korean earthquake resistant design method for slopes including alternatives of earthquake resistant design application according to designers' judgment considering construction budget, importance, restoration and so on. Afterwards, seismic data accumulation on slope stability of Korea is necessary to induce a more definite Korean earthquake resistant design method.

A Study on Legal Commentary Information Services Based on the Usage Patterns of Legal Information Sources (법률정보원 이용행태에 기반한 주석서 정보서비스에 관한 연구)

  • Won, Jong Sam;Lee, Jee Yeon
    • Journal of the Korean Society for information Management
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    • v.37 no.1
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    • pp.127-151
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    • 2020
  • The court has the responsibility to determine the final interpretation of the law. The court hands down final decisions on personal disputes and conflicts between individuals and the state. Legal commentaries will stay true to their intention of providing diverse legal theories and enabling a unified legal interpretation only when law practitioners are allowed to discuss in depth laws, cases, and legal theories within the boundaries set by commentary authors. If law practitioners include the latest laws, cases, and legal theories as well as their opinions to existing commentaries in their judicial roles and legal studies, they will be able to obtain a unified legal interpretation without referring to other legal literature.

Intracranial Endodermal Sinus Tumor (두개강내 내배엽성 동종양(Endodermal Sinus Tumor))

  • Lim, Yong Chull;Cho, Kyung Gi;Lee, Seong Un;Park, Han Jun;Shin, Yong Sam;Yun, Soo Han;Cho, Ki Hong
    • Journal of Korean Neurosurgical Society
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    • v.30 no.12
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    • pp.1381-1387
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    • 2001
  • Objective : Endodermal sinus tumor or yolk sac tumor is an uncommon malignant germ-cell neoplasm. This tumor was originally described as a germ cell tumor of the ovary or the testis. Intracranial endodermal sinus tumor is extremely rare and usually develop in the pineal or suprasellar regions. The authors evaluated the effect of adjuvant therapy(chemotherapy combined with radiotherapy) and radical removal of intracranial endodermal sinus tumors. Material and Methods : Between 1996 and 2001, four patients of intracranial endodermal sinus tumor were diagnosed with tumor marker(AFP) and biopsy. Three patients were treated with surgical removal and chemotherapy with cisplatin($20mg/m^2$), etoposide($100mg/m^2$) and bleomycin($15mg/m^2$) as well as external beam radiation therapy. We compared the management problems for these tumors. Result : In all three patients the tumor size and the level of tumor marker decresed during initial adjuvant therapy. However, Tumors showed regrowth with elevated AFP of serum and CSF possibly related to delayed chemotherapeutic treatment or inadequate administration of chemotherapeutic drugs due to severe bone marrow suppression. An additional chemotherapy and external radiation therapy were given, but tumors could not be controlled with leptomeningeal seeding. Conclusion : Radiotherapy is considered to be less effective. The combination chemotherapy with PVB(cisplatin, vinblastine, bleomycine) or PE(cisplatin, etoposide) is considered to be value in prolongation of the survival rate. But the role of chemotherapy in this tumor has not yet been clarified due to bone marrow suppression and drug resistance. Further study with large series of this tumor is necessary to establish the optimal management.

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The Effect of Extracellular Glutamate Release on Repetitive Transient Ischemic Injury in Global Ischemia Model

  • Lee, Gi-Ja;Choi, Seok-Keun;Eo, Yun-Hye;Kang, Sung-Wook;Choi, Sam-Jin;Park, Jeong-Hoon;Lim, Ji-Eun;Hong, Kyung-Won;Jin, Hyun-Seok;Oh, Berm-Seok;Park, Hun-Kuk
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.1
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    • pp.23-26
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    • 2009
  • During operations, neurosurgeons usually perform multiple temporary occlusions of parental artery, possibly resulting in the neuronal damage. It is generally thought that neuronal damage by cerebral ischemia is associated with extracellular concentrations of the excitatory amino acids. In this study, we measured the dynamics of extracellular glutamate release in 11 vessel occlusion(VO) model to compare between single occlusion and repeated transient occlusions within short interval. Changes in cerebral blood flow were monitored by laser-Doppler flowmetry simultaneously with cortical glutamate level measured by amperometric biosensor. From real time monitoring of glutamate release in 11 VO model, the change of extracellular glutamate level in repeated transient occlusion group was smaller than that of single occlusion group, and the onset time of glutamate release in the second ischemic episode of repeated occlusion group was delayed compared to the first ischemic episode which was similar to that of single 10 min ischemic episode. These results suggested that repeated transient occlusion induces less glutamate release from neuronal cell than single occlusion, and the delayed onset time of glutamate release is attributed to endogeneous protective mechanism of ischemic tolerance.

Astronomical Instruments with Two Scales Drawn on Their Common Circumference of Rings in the Joseon Dynasty

  • Mihn, Byeong-Hee;Choi, Goeun;Lee, Yong Sam
    • Journal of Astronomy and Space Sciences
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    • v.34 no.1
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    • pp.45-54
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    • 2017
  • This study examines the scale unique instruments used for astronomical observation during the Joseon dynasty. The Small Simplified Armillary Sphere (小簡儀, So-ganui) and the Sun-and-Stars Time-Determining Instrument (日星定時儀, Ilseong-jeongsi-ui) are minimized astronomical instruments, which can be characterized, respectively, as an observational instrument and a clock, and were influenced by the Simplified Armilla (簡儀, Jianyi) of the Yuan dynasty. These two instruments were equipped with several rings, and the rings of one were similar both in size and in scale to those of the other. Using the classic method of drawing the scale on the circumference of a ring, we analyze the scales of the Small Simplified Armillary Sphere and the Sun-and-Stars Time-Determining Instrument. Like the scale feature of the Simplified Armilla, we find that these two instruments selected the specific circumference which can be drawn by two kinds of scales. If Joseon's astronomical instruments is applied by the dual scale drawing on one circumference, we suggest that 3.14 was used as the ratio of the circumference of circle, not 3 like China, when the ring's size was calculated in that time. From the size of Hundred-interval disk of the extant Simplified Sundial in Korea, we make a conclusion that the three rings' diameter of the Sun-and-Stars Time-Determining Instrument described in the Sejiong Sillok (世宗實錄, Veritable Records of the King Sejong) refers to that of the middle circle of every ring, not the outer circle. As analyzing the degree of 28 lunar lodges (lunar mansions) in the equator written by Chiljeongsan-naepyeon (七政算內篇, the Inner Volume of Calculation of the Motions of the Seven Celestial Determinants), we also obtain the result that the scale of the Celestial-circumference-degree in the Small Simplified Armillary Sphere was made with a scale error about 0.1 du in root mean square (RMS).

Estimation of the Latitude, the Gnomon's Length and Position About Sinbeop-Jipyeong-Ilgu in the Late of Joseon Dynasty

  • Mihn, Byeong-Hee;Lee, Yong Sam;Kim, Sang Hyuk;Choi, Won-Ho;Ham, Seon Young
    • Journal of Astronomy and Space Sciences
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    • v.34 no.2
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    • pp.161-170
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    • 2017
  • In this study, the characteristics of a horizontal sundial from the Joseon Dynasty were investigated. Korea's Treasure No. 840 (T840) is a Western-style horizontal sundial where hour-lines and solar-term-lines are engraved. The inscription of this sundial indicates that the latitude (altitude of the north celestial pole) is $37^{\circ}$ 39', but the gnomon is lost. In the present study, the latitude of the sundial and the length of the gnomon were estimated based only on the hour-lines and solar-term-lines of the horizontal sundial. When statistically calculated from the convergent point obtained by extending the hour-lines, the latitude of this sundial was $37^{\circ}$ $15^{\prime}{\pm}26^{\prime}$, which showed a 24' difference from the record of the inscription. When it was also assumed that a convergent point is changeable, the estimation of the sundial's latitude was found to be sensitive to the variation of this point. This study found that T840 used a vertical gnomon, that is, perpendicular to the horizontal plane, rather than an inclined triangular gnomon, and a horn-shaped mark like a vertical gnomon is cut on its surface. The length of the gnomon engraved on the artifact was 43.1 mm, and in the present study was statistically calculated as $43.7{\pm}0.7mm$. In addition, the position of the gnomon according to the original inscription and our calculation showed an error of 0.3 mm.

The software configuration management system for image processing algorithm development (영상처리 알고리즘 개발을 위한 소프트웨어형상관리시스템)

  • Lee Jeong-Heon;Chae Ok-Sam
    • The KIPS Transactions:PartB
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    • v.12B no.1 s.97
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    • pp.1-8
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    • 2005
  • The importance of software is getting high in development of the digital device (digital camcoder, digital camera, mp3 player, ....). And because the sire of software becomes larger and complicated, the necessity of software configuration management (to solves a software crisis) is increased. The general software configuration management system shows lack of the property and features of software development environment for image processing algorithm due to its wide range to be covered. Image processing algorithm development environment has properties like repetitive analysis and simulation using visual programming environment where, beside support of elementary development functions. component(or library) can be combined and tested interactively. Moreover, the method to look fast and effectively for component having similar function is required. In this paper, we present the system which supports the software configuration management method for a simulation tool and the property in the visual programming environment. And we relate our system to real simulation tool so as to check its ability as the software configuration management system for image processing algorithm development environment.

A Study on the Development of Functional Cosmetics Using Silk-gland Powder of Silkworm (누에생실샘 미세분말을 이용한 기능성 화장품 소재 개발에 대한 연구)

  • Chon, Jeong-Woo;Kweon, Hae-Yong;Jo, You-Young;Park, Myung-Ki;Son, Yong-Ho;Lee, Heui-Sam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.2
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    • pp.163-169
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    • 2012
  • In this study, silk-gland powder of silkworm was investigated for the usefulness as a potential agent for functional cosmetics, total content of amino acids and DPPH free radical scavenging assay, and clinical trial were done. The analysis of the amino acids of silk-gland powder showed that serine (26.77 %) content was the highest and aspartic acid, glycine, and glutamic acid followed that. DPPH free radical scavenging activity of silk-gland powder was lower than vitamin C (82.3 % v.s. 97 %), The moisture and elasticity were increased in silk-gland powder compared to control cosmetics by 257.2 % and 181.15 %, relatively. These results suggest that silk-gland powder of silkworm may have beneficial properties as a material for cosmeceuticals.