• Title/Summary/Keyword: Th-227

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Equilibrium Growth of Allanite and Zircon during Amphibolite-facies Metamorphism (각섬암상 변성작용 중 갈렴석과 저어콘의 평형 성장)

  • Kim, Yoonsup
    • The Journal of the Petrological Society of Korea
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    • v.27 no.2
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    • pp.97-104
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    • 2018
  • The U-Pb isotopic and rare earth element compositions of zircon were measured using a SHRIMP from a tonalitic gneiss sample DE43 in Daeijak Island, central Korea. Zircon crystals, up to ${\sim}300{\mu}m$ in diameter, rarely contain thin overgrowth rims. In contrast to Paleoproterozoic cores, the $^{206}Pb/^{238}U$ ages of $256{\pm}23Ma(1{\sigma})$, and $221{\pm}7Ma(1{\sigma})$ were yielded from two spot analyses on the overgrowth rims of zircon. The rims are geochemically characterized by low Th/U ratios (<0.01) and strongly depleted light rare earth elements. The Permian-Triassic apparent ages of zircon are consistent with the $^{208}Pb/^{232}Th$ ages dated from allanite ($227{\pm}7Ma(t{\sigma})$) in the same sample within uncertainties, indicating an equilibrium growth of allanite and zircon at ~227 Ma. On the other hand, the younger $^{208}Pb/^{232}Th$ and $^{206}Pb/^{238}U$ ages ($213{\pm}4Ma(t{\sigma})$ and $186{\pm}9Ma(t{\sigma})$, respectively) of allanite may result from Pb loss due to the infiltration of alkali fluids from Late Triassic and Jurassic granitoids nearby.

Certain Polynomials Related to Chebyshev Polynomials

  • Kim, Seon-Hong
    • Journal of Integrative Natural Science
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    • v.4 no.3
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    • pp.227-228
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    • 2011
  • Bae and Kim displayed a sequence of 4th degree self-reciprocal polynomials whose maximal zeros are related in a very nice and far from obvious way. The auxiliary polynomials in their results that parametrize their coefficients are of significant independent interest. In this note we show that such auxiliary polynomials are related to Chebyshev polynomials.

Targeted alpha therapy (TAT) for cancer using metallic radioisotopes

  • Kang, Chi Soo;Lee, Kyo Chul;Lee, Yong Jin
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.5 no.2
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    • pp.135-144
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    • 2019
  • Targeted alpha therapy (TAT) based on metallic radionuclides has attracted a lot of attention lately due to its impressive therapeutic efficacy displayed in couple of clinical studies for cancer. Representative metallic radionuclides emitting alpha-particle include 225Ac, 213Bi, and 227Th, and there have been variety of TAT formulations based on different targeting moiety and chelating agents. In this review, we introduce strategies to label metallic radioisotopes with biomolecules and look at some of recent preclinical and clinical results of TAT for cancer.

Regulation of Intestinal Homeostasis by Innate Immune Cells

  • Kayama, Hisako;Nishimura, Junichi;Takeda, Kiyoshi
    • IMMUNE NETWORK
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    • v.13 no.6
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    • pp.227-234
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    • 2013
  • The intestinal immune system has an ability to distinguish between the microbiota and pathogenic bacteria, and then activate pro-inflammatory pathways against pathogens for host defense while remaining unresponsive to the microbiota and dietary antigens. In the intestine, abnormal activation of innate immunity causes development of several inflammatory disorders such as inflammatory bowel diseases (IBD). Thus, activity of innate immunity is finely regulated in the intestine. To date, multiple innate immune cells have been shown to maintain gut homeostasis by preventing inadequate adaptive immune responses in the murine intestine. Additionally, several innate immune subsets, which promote Th1 and Th17 responses and are implicated in the pathogenesis of IBD, have recently been identified in the human intestinal mucosa. The demonstration of both murine and human intestinal innate immune subsets contributing to regulation of adaptive immunity emphasizes the conserved innate immune functions across species and might promote development of the intestinal innate immunity-based clinical therapy.

CHARACTERISTICS OF A WATER-PURIFICATION SYSTEM USING IMMOBILIZED PHOTOSYNTHETIC BACTERIA BEADS

  • Kim, Joong-Kyun;Park, Kyoung-Joo;Cho, Kyoung-Sook;Nam, Soo-Wan;Kim, Yong-Ha
    • Environmental Engineering Research
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    • v.10 no.5
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    • pp.227-238
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    • 2005
  • The characteristics of nitrogen removal by the free cell and the immobilized cell of R. capsulatus were investigated. Denitrification by R. capsulatus cells resulted in reduction of ORP with the rapid depletion of DO and the increase of pH. Without accumulation of nitrite, the removal efficiencies of ${NO_3}^-$-N for the free cell and the immobilized cell were 99.1 and 99.3%, respectively. During the three-month experiment of goldfish breeding equipped with a water-purification biofilter, the average values of pH and total cell numbers present in an aquarium were not significantly different between water-purification system and the control. The average concentrations of ${NH_4}^+$-N and ${PO_4}^{2-}$-P in water-purification system were relatively low, compared to that in the control. Goldfish died at $11^{th}$, $16^{th}$, $43^{rd}$, and $67^{th}$ days in the control, while goldfish died at $10^{th}$, $20^{th}$, and $39^{th}$ days in the water-purification system. On the days of goldfish's death, the total concentrations of nitrogenous compounds except for ${NO_2}^--N$ were higher than those on the other days of the experiment, especially with the concentrations of ${NH_4}^+$-N ranging from 7.4 to 13.5 mg/L. The water-purification system also showed the less turbidity of water with more active movement of goldfish than the control. PVA gel beads showed almost the full denitrifying ability even after the long-term experiment. As a result, the water-purification system was effective to remove nitrogenous compounds with better survival of goldfish.

Isolation and Characteristics of Bacillus thuringiensis Strain BtTH109 which is Toxi against Root-Knot Nematode Meloidogyne incognita (토마토 뿌리혹선충 Meloidogyne incognita에 치사력이 있는 Bacillus thuuingiensis Bt TH109 균주의 분리 및 특성)

  • 이광배;김광현;김영희
    • Microbiology and Biotechnology Letters
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    • v.22 no.3
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    • pp.227-232
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    • 1994
  • In order to microbially control root-knot nematode(Meloidogyne incognita) in tomato, a strain BtTH109 of Bacillus thuringiensis producing root-knot nematocidal toxin was isolated. The strain BtTH109 was identified B. thuringiensis subsp. indiana(serotype 16) based on flagella antigenicity, biochemical properties, and morphological charcateristics. The strain BtTH109 have extracellularly produced a root-knot nematocidal toxin, which was very toxic against not only egghatch but also the 2nd-nematode larva of root-knot nematode in vitro.

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Effects of Peer Mentoring Program on the Health Conservation in Elderly Women with Osteoarthritis (동료멘토링 프로그램이 골관절염 여성노인의 건강보존에 미치는 효과)

  • Nam, Jiran;Sung, Kiwol
    • Research in Community and Public Health Nursing
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    • v.28 no.3
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    • pp.227-239
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    • 2017
  • Purpose: The purpose of this study was to investigate the effects of peer mentoring program on physical activity, knee joint function, self-care agency and social support, which are health conservation elements in elderly women with osteoarthritis. Methods: This study used a quasi-experimental research design. It is a pretest-and-post 1, post 2 test design of a non-equivalent control group. The subjects were elderly women aged over 65 who were diagnosed with osteoarthritis. A total of 60 patients (experimental group 30, control group 30) who registered with the Senior Welfare Center in City G and in Region D participated in this study. The data were collected from June 29th to September 4th, 2015. The collected data were analyzed with $x^2$ test, Fisher's exact test, independent t-test and repeated measurement ANOVA. Results: The experimental group showed a greater increase in physical activity, knee joint function, self-care agency and social support than the control group. Conclusion: The results indicated that the peer mentoring program is effective in increasing physical activity, knee joint function, self-care agency and social support of elderly women with osteoarthritis.

The Factors Related to Musculoskeletal Symptoms of Male Taxi Drivers (남성 택시 운전원의 근골격계 자각증상에 영향을 미치는 요인)

  • Eum, Mi-Jung;Jung, Hye-Sun
    • Korean Journal of Occupational Health Nursing
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    • v.23 no.4
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    • pp.227-234
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    • 2014
  • Purpose: This study was conducted to understand the subjective symptom rate of musculoskeletal disease of male taxi drivers and comprehend general features, health behavior features, and factors related to the subjective symptoms of musculoskeletal system depending on the level of job stress. Methods: The participants were 206 male taxi drivers from 4 transportation companies in the Seoul and Gyeonggi areas. The investigation was conducted from July 20th 2012 to August 20th 2012 through a self-administered questionnaire survey. Results: The participants who exercised less than three times per week complained about the subjective symptoms of the musculoskeletal system (p=.016) 13.770 times as more as than those of the participants who exercised more than three times per week the participants who had a higher level of job stress complained about the subjective symptoms of the muscular skeletal (p=.011) 1.051times as more as than those who had a relatively lower level of job stress. Conclusion: This study recommends that it is necessary to provide exercise programs and arrange various plans reducing job stress to prevent muscular skeletal disease and minimize the disease susceptibility of taxi drivers.

A Study on the Ecocentric Worldview of Elementary School Students (초등학교 4-6학년 학생들의 생태중심 세계관에 대한 연구)

  • Kim, Hee-Seok;Paik, Seoung-Hey
    • Journal of Korean Elementary Science Education
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    • v.40 no.2
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    • pp.227-238
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    • 2021
  • Ecocentric worldview is considered as worldview that overcomes present environment problems and increases animal right. This study explores the formation of an ecocentric worldview for 4th-6th graders based on Peter Singer's research that divides the development of morality into family-centered, species-centered, and ecocentric worldview. The subjects of this study were 77 4th graders, 84 5th graders, and 91 6th graders in Daegu Metro- politan City. The results of surveying students' worldview based on the questionnaire developed by dividing into 6 questions are as follows. In most of the items in grades 4-6, the rate of formation of a species-centered worldview or a family-centered worldview was higher than that of an ecocentric worldview. However, in the case of 6th grade students was significantly higher than in other grades because they learned lesson on wolf restoration in the 5th grade science class. This may be seen as an effect of education, but since the ecocentric worldview did not appear high in other questions, it is reasonable to assume that 6th graders simply recited what they learned rather than forming a true ecocentric worldview. Therefore, there is a need for education that can help students to think, judge, and act on the basis of the ecocentric worldview consistently in any situation, rather than just memorizing the knowledge of the ecocentric worldview learned.