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Introducing the History of Science in Modem Korea into the Elementary Classroom (한국 근현대 과학사의 초등교육 활용 방안)

  • Moon, Man-Yong
    • Journal of Korean Elementary Science Education
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    • v.28 no.2
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    • pp.197-212
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    • 2009
  • The purpose of this study is to investigate the possibility of introducing the history of science in modern Korea into elementary education. Although there are many studies on applying a history of science to science education, they do not pay attention to the history of science in modern Korea. I survey research papers on the history of science in modern Korea and science education based on a history of science, and elementary science textbooks in Korea, Japan and the US. When we apply the history of science in modern Korea into elementary education, elementary students will recognize science has close relations to Korean culture and history and they will develop the familiarity with science. I show there are 3 ways using the history of science in modern Korea in elementary education: 1) Applying Korean scientists' research contents to science education, 2) Measures to evaluate Korean scientists correctly, 3) Materials for science education programs for gifted elementary students.

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A Simpler Structured Nonparametric Detector with Reference Observations for Random Signals in Multiplicative Noise (적산성 잡음에서 참고 관측량을 쓰는 간단한 구조의 비모수 확률 신호 검파기)

  • Park, Ae-Kyung;Song, Iick-Ho;Bae, Jin-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.4C
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    • pp.379-383
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    • 2003
  • A simpler nonparametric detector test statistic based on reference observation in addition to the rank statistics of regular observations is suggested in this letter. Using reference observations instead of sign statistics helps us a simpler detector structure especially for random signals buried in multiplicative noise.

A Study on the Air Defense Capability of Aegis Class Ships the Netted Battlefield (전장네트워크 기반 이지스급 함정의 공중방어능력에 관한 연구)

  • 임희동;권용수
    • Journal of the military operations research society of Korea
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    • v.28 no.2
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    • pp.137-150
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    • 2002
  • This paper describes a comprehensive analysis of the air defense capability of Aegis class ships on the netted battlefield. A principal threat to ships at sea is anti-ship cruise missiles. The missiles flies lower, faster, and with less radar cross section than its predecessors. Therefore, the ship of the 21s1 century must have the future operational capability based NCW to engage this threat and then the survivability of ship can be guaranteed. This operational concept is reflected in Aegis ship and CEC of US navy, In the near future, the korean navy will be possessed a few Aegis class ships. In this view, this paper has analyzed the intercept range of the sea-skimming ASCM to measure the area defense capability of the Aegis ship in PCW and NCW, respectively and presented the air defense capability of the ship on the netted battlefield.

Workpiece Horizontality and Reference Positioning of Cutting Tool by Measuring Impedance in Ultra-Precision-Machining (초정밀가공 시 임피던스 측정을 통한 시편 수평맞춤 및 공구의 기준위치 설정)

  • Lee, Ho-Cheol;Kim, Gi-Dae
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.12
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    • pp.1366-1371
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    • 2011
  • In ultra precision machining, it is necessary to adjust the horizontality and reference position of a workpiece in a noncontact manner. For this, a simple process by measuring impedance between a tool tip and a workpiece which are connected to impedance analyzer is proposed. As the distance between the tool and the workpiece gets closer, the reduction rate of impedance becomes higher over all frequency ranges. By setting threshold value of impedance reduction rate at specific frequencies through preliminary experiments, the distance between the tool and the workpiece can be predicted and it directly enables us to horizontalize the workpiece and to set the tool to the desired reference position.

The distribution of magnetic field strength in Orion A region

  • Hwang, Jihye;Kim, Jongsoo
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.43.3-43.3
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    • 2019
  • Magnetic fields play an important role in supporting molecular clouds against gravitational collapse. The measured magnetic field strengths in molecular clods enable us to see the effect of magnetic fields in star-forming regions. People have used the Chandrasekhar and Fermi (CF) method to estimate magnetic field strength from observational quantities of molecular cloud density, turbulent velocity and polarization angle dispersion. However, previous studies obtained just one magnetic field strength over the quite large region of a molecular cloud by using the CF method. We here suggest a way to estimate magnetic field strength distribution in Orion A region. We used 450 and 850-micron polarization data of James Clerk Maxwell Telescope (JCMT). Magnetic field strengths were estimated in two wavelengths with 4 pixel resolutions of 16, 20, 24 and 28". Through statistical analysis, we proved the difference of magnetic field strengths between two wavelengths were caused by the difference of their beam sizes. Additionally, we calculated the radii of curvature of polarization segments to select a best pixel resolution for estimating the magnetic field distribution. The pixel resolution should be larger than a radius of curvature. We selected that 20 or 24" pixel resolutions are good choices towards Orion A region.

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Gardenia jasminoides extract and its constituent, genipin, inhibit activation of CD3/CD28 co-stimulated CD4+ T cells via ORAI1 channel

  • Kim, Hyun Jong;Nam, Yu Ran;Woo, JooHan;Kim, Woo Kyung;Nam, Joo Hyun
    • The Korean Journal of Physiology and Pharmacology
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    • v.24 no.4
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    • pp.363-372
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    • 2020
  • Gardenia jasminoides (GJ) is a widely used herbal medicine with anti-inflammatory properties, but its effects on the ORAI1 channel, which is important in generating intracellular calcium signaling for T cell activation, remain unknown. In this study, we investigated whether 70% ethanolic GJ extract (GJEtOH) and its subsequent fractions inhibit ORAI1 and determined which constituents contributed to this effect. Whole-cell patch clamp analysis revealed that GJEtOH (64.7% ± 3.83% inhibition at 0.1 mg/ml) and all its fractions showed inhibitory effects on the ORAI1 channel. Among the GJ fractions, the hexane fraction (GJHEX, 66.8% ± 9.95% at 0.1 mg/ml) had the most potent inhibitory effects in hORAI1-hSTIM1 co-transfected HEK293T cells. Chemical constituent analysis revealed that the strong ORAI1 inhibitory effect of GJHEX was due to linoleic acid, and in other fractions, we found that genipin inhibited ORAI1. Genipin significantly inhibited IORAI1 and interleukin-2 production in CD3/CD28-stimulated Jurkat T lymphocytes by 35.9% ± 3.02% and 54.7% ± 1.32% at 30 μM, respectively. Furthermore, the same genipin concentration inhibited the proliferation of human primary CD4+ T lymphocytes stimulated with CD3/CD28 antibodies by 54.9% ± 8.22%, as evaluated by carboxyfluorescein succinimidyl ester assay. Our findings suggest that genipin may be one of the active components of GJ responsible for T cell suppression, which is partially mediated by activation of the ORAI1 channel. This study helps us understand the mechanisms of GJ in the treatment of inflammatory diseases.

Variation in the Resistance of Japanese Soybean Cultivars to Phytophthora Root and Stem Rot during the Early Plant Growth Stages and the Effects of a Fungicide Seed Treatment

  • Akamatsu, Hajime;Kato, Masayasu;Ochi, Sunao;Mimuro, Genki;Matsuoka, Jun-ichi;Takahashi, Mami
    • The Plant Pathology Journal
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    • v.35 no.3
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    • pp.219-233
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    • 2019
  • Soybean cultivars susceptible to Phytophthora root and stem rot are vulnerable to seed rot and damping-off of seedlings and young plants following an infection by Phytophthora sojae. In this study, the disease responses of Japanese soybean cultivars including currently grown main cultivars during the early growth stages were investigated following infections by multiple P. sojae isolates from Japanese fields. The extent of the resistance to 17 P. sojae isolates after inoculations at 14, 21, and 28 days after seeding varied significantly among 18 Japanese and two US soybean cultivars. Moreover, the disease responses of each cultivar differed significantly depending on the P. sojae isolate and the plant age at inoculation. Additionally, the treatment of 'Nattosyo-ryu' seeds with three fungicidal agrochemicals provided significant protection from P. sojae when plants were inoculated at 14-28 days after seeding. These results indicate that none of the Japanese soybean cultivars are completely resistant to all tested P. sojae isolates during the first month after sowing. However, the severity of the disease was limited when plants were inoculated during the later growth stages. Furthermore, the protective effects of the tested agrochemicals were maintained for at least 28 days after the seed treatment. Japanese soybean cultivars susceptible to Phytophthora root and stem rot that are grown under environmental conditions favorable for P. sojae infections require the implementation of certain practices, such as seed treatments with appropriate agrochemicals, to ensure they are protected from P. sojae during the early part of the soybean growing season.

Pap Smear Screening Results for Turkish Pregnant Women

  • Dinc, Ayten
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5835-5838
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    • 2012
  • Objective: Cervix cancer is one of the most common gynecological cancer types that cause cancer deaths among women. This study was planned based on a descriptive method in order to evaluate the results of PAP smear screening during pregnancy for prevention of cancer. Materials and Methods: The research involved 110 pregnant women registered at the Obstetrics and Gynecology Polyclinic of Bagcilar Training and Research Hospital and 86 non-pregnant women of the same ages as a control group. As criteria for acceptance were conditions such as not being in coitus within the last 48 hours, not using vaginal ovule, and not performing vaginal lavage. A survey consisting of 33 questions was conducted and the results were processed using Bethesda. Results: The average ages were $27.1{\pm}4.70$ for the pregnant women and $28.8{\pm}4.24$ for the control group. 60.7% of cases had previously heard of a PAP smear test, 49% were aware of why PAP smear tests were conducted, 26.4% of pregnant participants and 27.3% of non-pregnant participants had previously undergone a smear test. In this study, smear results of all cases were 95.4% sufficient. 18.2% of pregnant cases had an infection, 54.5% had reactive cellular change, and 0.9% had atypical squamous cells of undetermined significance (ASC-US). 16.3% of non-pregnant cases had an infection, 58.1% had reactive cellular change, 3.5% had atypical squamous cells of undetermined significance (ASC-US), and 1.2% had low-grade squamous intraepithelial lesions (LGSIL). Conclusion: PAP smear test is a good opportunity to identify pre-invasive lesions in early phases of pregnancy.

Genotype Distribution of Human Papillomavirus in Women with Abnormal Cervical Cytology in an Esophageal Carcinoma High Incidence Area of China

  • Mai, Rui-Qin;Huang, Bo;Shen, Ling;Zhang, Guo-Hong;Hong, Liang-Li;Cai, Ying-Mu
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.4945-4950
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    • 2014
  • Infection with human papillomavirus (HPV) could affect genesis of both cervical and esophageal cancers. The type-specific distribution of HPV in cervical cytology abnormalities of women has remained unclear in Shantou, an esophageal cancer high-incidence area of China. Data from 22,617 women who were subjected to cervical HPV DNA testing with simultaneous cervical cytological examination during 2009-2013 were therefore here retrospectively evaluated in a hospital-based study. Overall, 16.2% (3,584/22,114)of women with normal cytology were HR-HPV positive, with HPV-52 (4.07%) as the most common type followed by -16 (3.63%), and -58 (2.46%). Prevalence of HR-HPV was 50.3% (253/503) in women with cervical cytological abnormalities, of which in ASC-H 71.4%, ASC-US 39.1%, HSIL 80.3% and LSIL 73.7%. HPV-58 (14.12%) was the most common type for all cervical cytological abnormalities, followed by HPV-16 (13.72%), and -52 (12.72%), while the more common HPV-16 type in ASC-H (42.9%) and HSIL (36.1%), HPV-52 and -58 were the most common types for ASC-US (10.3%) and LSIL (25%), respectively. Multiple HPV co-infections were identified in 33.2% (84/253) cytology abnormalities with positive HR-HPV, and the highest prevalence of HPV-58/16 combination in HSIL (28.6%, 6/21) was observed. Our data indicated a relative high prevalence of HPV-58 and -52 in women with cervical cytological abnormalities, which should be considered in the development of next-generation vaccines for Shantou.

Factors Associated with Periductal Fibrosis Diagnosed by Ultrasonography Screening among a High Risk Population for Cholangiocarcinoma in Northeast Thailand

  • Intajarurnsan, Sutheera;Khuntikeo, Narong;Chamadol, Nittaya;Thinkhamrop, Bandit;Promthet, Supannee
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.8
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    • pp.4131-4136
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    • 2016
  • Background: The population in northeast Thailand continues to present with hepatobiliary abnormalities, particularly periductal fibrosis (PDF) which is the result of chronic infection with liver fluke (Opisthorchis viverini; OV) and may lead to the development of cholangiocarcinoma (CCA). Although the prevalence of OV infection has been decreased due to a liver fluke control program over decades, the prevalence of PDF remains high. This study aimed to investigate demographic factors associated with PDF risk based on ultrasonography (US) screening. Materials and Methods: This cross-sectional study is part of the Cholangiocarcinoma Screening and Care Program (CASCAP), a prospective cohort study. Multiple logistic regression was used for data analysis. Results: In 55,246 subjects, the overall prevalence of PDF was 33.0% (95%CI: 32.6 - 33.4). Males (33.9 %) were at higher risk for developing PDF than females (32.2 %) (ORcrude = 0.93; 95%CI: 0.89 - 0.96; p-value < 0.001). Factors associated with an increased PDF risk, in addition to OV infection, included old age (${\geq}70$ years) (ORadj = 1.28, 95% CI: 1.14 - 1.44, p < 0.001) and hepatitis B infection (ORadj = 1.31, 95% CI: 1.11 - 1.55, p = 0.001). In contrast, number of praziquantel treatments (> 2 times) (ORadj = 0.54, 95% CI: 0.47 - 0.63, p < 0.001) and diabetes mellitus (ORadj = 0.57, 95% CI: 0.49 - 0.65, p < 0.001) were significantly associated with a decreased PDF risk. Conclusions: Future US screening should closely examine older people and hepatitis B subjects for the purpose of PDF surveillance among high risk groups for CCA. However, the results of inverse associations require further investigation in order to confirm our findings.