• Title/Summary/Keyword: biological sample

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Phantom Evaluation and Development of Photoacoustic Tomography Imaging System using Unfocused Ultrasound Transducer and Back-Projection Algorithm (역투사 알고리듬과 비촛점 트랜스듀서를 적용한 광음향 단층영상 장치개발과 팬텀실험)

  • Ryu, Sang-Hun;Kim, Do-Hyun;Song, Chul-Gyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.12
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    • pp.2349-2351
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    • 2010
  • Photo Acoustic Tomography (PAT) is a hybrid imaging modality which combines high contrast of optical imaging and spatial resolution of ultrasound imaging, thus it is suitable to image biological tissue noninvasively. Laser-induced photoacoustic signals were measured from a sample by means of an unfocused ultrasound transducer, then PAT image was reconstructed based on a universal back-projection algorithm. To evaluate the feasibility of our system, phantom test was performed, consequently, the PAT images obtained using our system showed highly analogous shape and volume with those of the phantom. This result demonstrated that our system can provide a powerful tool for imaging the substructure of biological tissue in non-invasive manner.

Variations of Catecholamine Contents in Rat Urine by Environmental Stress (환경 Stress에 의한 횐쥐뇨중 catecholamine의 변화)

  • 김형석
    • Environmental Analysis Health and Toxicology
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    • v.3 no.3_4
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    • pp.9-15
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    • 1988
  • The word of stress crime from Latin language as stringere and it was used in medical fields from 1935. According to Selye, all the biological bodies reveal physilolgical changes when some stimulation exceed normal levels, and consequently the pituitary gland and adrenal systems are activated. Jacob expressed that stress is the loss of homeostasis by physical, chemical, and emotional stimulation. When biological organisms receive extreme stress the amount of catecholamine excretion are increase. Author investigated the catecholamine contents in rat urine after giving the low temperature stress, noise stress, and water immersion stress. The 24 hours rat urine was collected by adding 1 ml 6 N-HCl and the sample is passed through Bio-Rex 70 samples treatment column to extract catecholamine and detected the catecholamine with HPLC-fluorescence detetor. The highest epinephrine concentration was 67.14 ng in water immersion stress condition and the dopamine concentration of 221.37 ng was shown in the low temperature stress condition.

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A Mueller Matrix Study for Measuring Thermal Damage Levels of Collagenous Tissues

  • Jun, Jae-Hoon
    • Journal of Biomedical Engineering Research
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    • v.27 no.6
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    • pp.310-317
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    • 2006
  • Extensive research with polarimetry and Mueller matrix has been done for chemical measurements and possible cancer detection. However, the effect of thermally denatured biological tissue on polarization changes is not well known. The purpose of this study is to characterize polarization changes in collagen due to thermal denaturation. The variations in polarized state caused by thermal damage were investigated by obtaining the Mueller matrix elements of collagen sample at multiple thermal damage levels. The changes in birefringence of denatured collagen were also investigated. This information could be used to determine the extent of thermal damage level of clinically heat treated tissues.

Marine Molluscan Fauna of Jindo Island

  • Lee, Yucheol;Choe, Yeongjae;Shin, Youngheon;Kim, Taeho;Park, Jina;Park, Joong-Ki
    • Animal Systematics, Evolution and Diversity
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    • no.spc9
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    • pp.30-36
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    • 2016
  • As a part of the commemorative joint faunal survey for the 30th anniversary of the Korean Society of Systematic Zoology, the molluscan fauna of Jindo Island was investigated based on sample collection from 6 localities from the 6 to the 8 of Jul 2016. A total of 114 molluscan species from 47 families were collected and identified. Among these, 42 species from 11 families are newly reported from Jindo Island and combining the previous records with the present study totals 157 species from 57 families. Distribution of species records indicates that marine biogeography of Jindo Island represent an overlapping zone for marine organisms which dwell in the Yellow sea and the southern sea areas of Korean waters.

Speckle Reduction in the Wavelet Domain for Image with Optical Coherence Tomography

  • Chang, Ju-Wan;Lee, Chang-Su;Na, Ji-Hoon;Paes, Stephane;Lee, Byeong-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2459-2463
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    • 2005
  • Optical coherence tomography (OCT) is high resolution medical imaging system which is obtaining image inside biological objects with non-destructive method. OCT system is based on Michelson interferometer with a reciprocating mirror in the reference arm and a biological object in the sample arm. The obtained OCT image suffers from a granular or mottled image, called speckle. Speckle is caused by random interferences between reflected coherence waves. In this paper, we propose effective speckle reduction method that uses wavelet transform. With wavelet domain image, sub-windowing and thresholding are performed. Finally, speckle reduction experiments for Misgurnus mizolepis skin and rat eye images are shown.

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Ni-P Coated Sn Powders as Anode for Lithium Secondary Batteries

  • Jo, Yong-Nam;Im, Dong-Min;Kim, Jae-Jung;Oh, Seung-M.
    • Journal of the Korean Electrochemical Society
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    • v.10 no.2
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    • pp.88-93
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    • 2007
  • Nano-sized Sn particles were coated with Ni-P layer using an electroless deposition method and their anodic performance was tested for lithium secondary batteries. Uniform coating layers were obtained, of which the thickness was controlled by varying the $Ni^{2+}$ concentration in the plating bath. It was found that the Ni-P layer plays two important roles in improving the anodic performance of Sn powder electrode. First, it prevents the inter-particle aggregation between Sn particles during the charge/discharge process. Second, it provides an electrical conduction pathway to the Sn particles, which allows an electrode fabrication without an addition of conductive carbon. A pseudo-optimized sample showed a good cyclability and high capacity ($>400mAh\;g^{-1}$) even without conductive carbon loading.

Label-Free Molecular Imaging of Living Cells

  • Fujita, Katsumasa;Smith, Nicholas Isaac
    • Molecules and Cells
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    • v.26 no.6
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    • pp.530-535
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    • 2008
  • Optical signals based on Raman scattering, coherent anti-Stokes Raman scattering (CARS), and harmonic generation can be used to image biological molecules in living cells without labeling. Both Raman scattering and CARS signals can be used to detect frequencies of molecular vibrations and to obtain the molecular distributions in samples. Second-harmonic optical signals can also be generated in structured arrays of noncentrosymmetric molecules and can be used to detect structured aggregates of proteins, such as, collagen, myosin and tubulin. Since labeling techniques using chemical and biological reactions may cause undesirable changes in the sample, label-free molecular imaging techniques are essential for observation of living samples.

A Fluorometric Assay for Trypsin Inhibitor (트립신 저해단백질의 형광측정법)

  • Jung, Jin;Lee, Chun-Young
    • Applied Biological Chemistry
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    • v.25 no.3
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    • pp.182-188
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    • 1982
  • A fluorometric method is described which permits the assay of trypsin inhibitor contained in a sample in an extremely small amount, utilizing a novel reagent generally called fluorescamine. The fluorometric assay with an enzyme kinetic approach has been found to be at least 100 times more sensitive than the well-known Kunitz's spectrophotometric method, considerably taster and less complicated, when it was demonstrated with the anti tryptic activities of very dilute extracts from soybean, red-bean and mung bean. Details of experimental procedure as well as theoretical considerations will be discussed.

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Evaluation of Rapid Immunochromatographic Assay Kit for HBsAg-Screening Using Whole Blood

  • Shin, Hyeong-Soon;Heo, Tae-Ryeon
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.5
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    • pp.362-365
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    • 2000
  • A rapid immunochromatographic assay kit using whole blood to screen hepatitis B surface antigen was developed and evaluated by using sera from 240 patients. The reference diagnosis was based on the results obtained with GENEDIA Anti-HBs Rapid kit which is very similar to the above kit except for the use of serum. The test demonstrated a good correlation with the reference immunochromatographic assay kit, that is, the sensitivity and the specificity of the kit was 100%, respectively. The rapid test kit using whole blood should be more convenient and useful for the diagnosis of hepatitis B virus because the kit does not need machines and time to prepare serum. In addition, this kit is safe from inadvertent infection during sample treatment because the blood is sterilized with hydrogen peroxide, eliminates the procedure required to prepare serum and reduces the possibility of exposure to infectious agents.

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Plant CLASSIFICATION CONCEPTS OF KOREAN ELEMENTARY AND SECONDARY STUDENTS (한국(韓國) 초(初), 중(中), 고등학교(高等學校) 학생(學生)들의 식물분류(植物分類) 기념(機念)에 관한 연구)

  • Chung, Wan-Ho;Hur, Myung;Cha, Hee-Young
    • Journal of The Korean Association For Science Education
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    • v.11 no.1
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    • pp.25-36
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    • 1991
  • For the purpose of extending the fields of biological preconceptual studies, the conceptions of plant classification, which have not been researched on them in korea, were selected and a questionnaire were administered to a sample of a total of 965 students at elementary and secondary school levels of korea. Many elementary school students have the alternative conceptions that plants are not alive. The misconceptions in plant classification are partly caused by the uncertainty of biological terms. To serve the teachers, who have difficulty in teaching them, the preceeding results are summarised with Composition the misconception maps.

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