• Title/Summary/Keyword: Molecular Characteristics

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Optical and electrical properties of the PAAS L films and LB films observed by BAM (BAM으로 관측한 PAAS L막의 특성 및 LB막의 광학적, 전기적 특성에 관한 연구)

  • Lee, Seung-Yop;Kim, Tae-Wan;Kang, Dou-Yol
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1725-1727
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    • 1996
  • Brewster angle microscopy(BAM) makes it possible to measure domains of Langmuir films. Especially, formation and phase transition of the PAAS Langmuir monolayers from a gas phase to a solid phase at the air-water interface were observed by the use of BAM. And also we observed the comparative images of films deposited at each phase. The UV/visible absorption spectra of this films showed molecular intensity and aggregation at each state. The electrical properties of this material were measured by current-voltage(I-V) characteristics.

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Properties of Electric Sofety for Dielectric Loss of Aging Natural Rubber. (노화된 천연고무의 유전손실에 관한 전기안전특성)

  • 이성일;권호영
    • Journal of the Korean Society of Safety
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    • v.6 no.4
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    • pp.5-12
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    • 1991
  • The dielectric properties of natural rubbers for electric safety are very important to investigate the molecular structure. The electric safety characteristics of the dielectric absorption in aging vulcanized natural rubber were studied in the range of frequency from 1$\times$10$^3$[Hz]to 3.2$\times$10$^3$[Hz]l at the temperature of 23[$^{\circ}C$]. As the results, it has been confirmed that in the case of aging natural rubber of above 2 phr the specimens exhibit two kinds of dielectric losses due to the dipole polarization by impurities and sulfurs, and of raw rubber exhibit the kind of losses due to the dipole polarization. Rurthermore, dielectric loss maximum tansspectrum in high freguency region for electric safety, which removed to the low freguency according to increasing sulfur, depends greatly on sulfur.

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Evaluation of Melanoidins Formed from Black Garlic after Different Thermal Processing Steps

  • Kang, Ok-Ju
    • Preventive Nutrition and Food Science
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    • v.21 no.4
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    • pp.398-405
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    • 2016
  • The objective of this study was to evaluate the characteristics of melanoidins formed from black garlic (BG) after different thermal processing steps. The melanoidins formed from BG during thermal processing were produced in large amounts, and the initial (280 nm), intermediate (360 nm), and final stage product (420 nm) had similar tendencies. Compounds like degraded proteins, peptides, and phenolic acids were present in the melanoidins during thermal processing. All the melanoidin samples showed different absorptions in the UV-visible spectra, although these had similar shapes. Moreover, the carbon, hydrogen, and oxygen content of melanoidins formed from BG during thermal processing decreased initially, and then increased. However, the nitrogen content increased during thermal processing. As thermal processing progressed, the molecular weight of all the melanoidin samples showed increasing intensities, whereas the major peaks of each melanoidin sample had different retention times. Furthermore, the melanoidins formed from BG after different thermal processing steps contained -OH, -CH, amide I, and III groups. The crystallinity of the melanoidins was majorly formed at $31.58^{\circ}$ and $43.62^{\circ}$ ($2{\theta}$).

Characterization of dnaK Mutants in Streptococcus pneumoniae

  • Kim, Seung-Whan;Pyo, Suhk-Neung;Rhee, Dong-Kwon
    • BMB Reports
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    • v.33 no.1
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    • pp.75-81
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    • 2000
  • DnaK is a major heat shock protein and known to be highly conserved in all species. Previously, the dnaK in Streptococcus pneumoniae was cloned and the immunogenic nature characterized. In this study, dnaK mutants were generated by insertion of duplication mutagenesis and their characteristics examined. They had defective growths at all temperatures ($20^{\circ}C-42^{\circ}C$)and cell divisions, and formed filaments after a temperature shift from 30 to 42. A unique feature of the dnaK mutants of S. pneumoniae, unlike those of E. coli and B. subtilis, was the growth capability at high temperature ($42^{\circ}C$) without producing the putative GroEL. Our results suggest that DnaK may serve as a regulator and/or modifier in GroEL gene expression.

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Glioblastoma multiforme: a perspective on recent findings in human cancer and mouse models

  • Lim, Sang-Kyun;Llaguno, Sheila R. Alcantara;McKay, Renee M.;Parada, Luis F.
    • BMB Reports
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    • v.44 no.3
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    • pp.158-164
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    • 2011
  • Gliomas are the most frequently occurring primary malignancies in the central nervous system, and glioblastoma multiforme (GBM) is the most common and most aggressive of these tumors. Despite vigorous basic and clinical studies over past decades, the median survival of patients with this disease remains at about one year. Recent studies have suggested that GBMs contain a subpopulation of tumor cells that displays stem cell characteristics and could therefore be responsible for in vivo tumor growth. We will summarize the major oncogenic pathways abnormally regulated in gliomas, and review the recent findings from mouse models that our laboratory as well as others have developed for the study of GBM. The concept of cancer stem cells in GBM and their potential therapeutic importance will also be discussed.

Preparation and Characteristics of Polypropylene Nonwoven Fabric Grafted by Styrene (스티렌 그라프트 폴리프로필렌 부직포의 제조와 특성)

  • Kim, Sang-Yool;Na, Choon-Ki
    • Fashion & Textile Research Journal
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    • v.6 no.3
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    • pp.377-383
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    • 2004
  • Photografting of styrene (St) on polypropylene (PP) nonwoven fabric using benzoin ethyl ether (BEE) as a photosensitizer was investigated. Inhibition of homopolymerization was achieved by adding various concentrations of $FeSO_4{\cdot}7H_2O$, $CuSO_4{\cdot}5H_2O$ and Mohr's salt. As St concentration was increased, the degree of grafting was increased as to a specific value and then decreased, and the effect of BEE concentration showed the same tendency. It was also found that the degree of grafting increased with reaction time and reaction temperature. Addition of the polyfunctional monomers and $H_2SO_4$ to the grafting system accelerated the photografting. The melting temperature, molecular weight, tensile strength and elongation were decreased with the increase in the degree of grafting.

Recent Progress in Triple Negative Breast Cancer Research

  • Mouh, Fatima Zahra;El Mzibri, Mohammed;Slaoui, Meriem;Amrani, Mariam
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1595-1608
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    • 2016
  • Triple-negative breast cancer (TNBC) is defined as a type of breast carcinoma that is negative for expression of oestrogene and progesterone hormone receptors (ER, PR) and HER2. This form of breast cancer is marked by its aggressiveness, low survival rate and lack of specific therapies. Recently, important molecular characteristics of TNBC have been highlighted and led to the identification of some biomarkers that could be used in diagnosis, as therapeutic targets or to assess the prognosis. In this review, we summarize recent progress in TNBC research focusing on the genetic and epigenetic alterations of TNBC and the potential use of these biomarkers in the targeted therapy for better management of TNBC.

Data Mining for Identification of Molecular Targets in Ovarian Cancer

  • Villegas-Ruiz, Vanessa;Juarez-Mendez, Sergio
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1691-1699
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    • 2016
  • Ovarian cancer is possibly the sixth most common malignancy worldwide, in Mexico representing the fourth leading cause of gynecological cancer death more than 70% being diagnosed at an advanced stage and the survival being very poor. Ovarian tumors are classified according to histological characteristics, epithelial ovarian cancer as the most common (~80%). We here used high-density microarrays and a systems biology approach to identify tissue-associated deregulated genes. Non-malignant ovarian tumors showed a gene expression profile associated with immune mediated inflammatory responses (28 genes), whereas malignant tumors had a gene expression profile related to cell cycle regulation (1,329 genes) and ovarian cell lines to cell cycling and metabolism (1,664 genes).

Miuraea migitae, a new record of the order Bangiales (Bangiophyceae, Rhodophyta) from Korea

  • Koh, Young Ho;Lee, Hyung Woo;Kim, Myung Sook
    • Fisheries and Aquatic Sciences
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    • v.19 no.9
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    • pp.38.1-38.5
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    • 2016
  • We found specimens of foliose Bangiales from the subtidal zone of Udo, Jeju Island, Korea. In molecular analyses of rbcL sequences, these Korean specimens were almost identical to Miuraea migitae from Osaka, Japan. In the morphological comparison, Korean specimens were consistent with habitat, color, and vegetative characteristics with the description of M. migitae. This is the first record of M. migitae outside the type locality and Nagasaki in Japan. This study confirms that new or unrecorded species of the order Bangiales may be discovered from subtidal habitats.

Characteristics of Antitumorial Antibiotics B-1123 from Aspergillus terreus (Aspergillus terreus 균주가 생산하는 항암항생물질 B-1123의 성상)

  • 박부길;박현묵;이진하;함승시;한재우
    • Microbiology and Biotechnology Letters
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    • v.18 no.4
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    • pp.331-337
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    • 1990
  • An antitumor antibiotic named B-1123 substance was isolated from the culture filtrate of a new isolate fungus identified as Aspergillus terreus. The fermentation yield reached about 23 mg per liter of the broth. The B-1123 substance, chlorine containing antibiotic, has the molecular formular of $C_{17}H_{12}0_7C_{12}$. Its structure was determined to be geodin by spectroscopic data. It is active against some Gram-positive bacteria and it prolongs the life span of mice inoculated with Ehrlich carcinoma.

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