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A Study on Development of Early Childhood Teacher's Guidance Efficacy Scale (유아교사의 생활지도 효능감 척도개발 연구)

  • Choi, Yeun Hwa
    • Korean Journal of Child Education & Care
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    • v.19 no.2
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    • pp.165-176
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    • 2019
  • Objective: The purpose of this study is to develop a measure of the Early Childhood Teacher's Guidance Efficacy Scale based on guidance and teacher-efficacy theory. Methods: This subjects were 243 teachers in Seoul and Gyeonggi-do. Results: An exploratory factor analysis was conducted on the data collected of 4 factors, namely, guidance efficacy for problem behavior, children understanding, home-connected, basic life habits. In addition, there are significant positive correlations between the sub-area score and the overall in the early childhood teacher's guidance efficacy scale(r = .26 ~ .72, p < .001). Internal consistency and split-half reliability of each sub scale were reasonably accept. Conclusion/Implications: 'The guidance efficacy scale for early childhood teachers' developed in this study is an appropriate tool. Therefore, the developed scale can become a useful tool to measure the overall guidance efficacy level of early childhood teachers.

Purification and Characterization of Metalloprotease from Serratia marcescens PPB-26 and Its Application for Detergent Additive

  • Thakur, Shikha;Sharma, Nirmal Kant;Thakur, Neerja;Bhalla, Tek Chand
    • Microbiology and Biotechnology Letters
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    • v.47 no.2
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    • pp.259-268
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    • 2019
  • In this study, the extracellular metalloprotease from Serratia marcescens PPB-26 was purified to homogeneity via ethanol fractionation and DEAE-cellulose column chromatography. Thus, a 3.8-fold purification was achieved with a 20% yield and specific activity of 76.2 U/mg. The purified protease was a 50-kDa monomer whose optimum pH and temperature for activity were 7.5 and $30^{\circ}C$ respectively; however, it was found to remain active in the 5-9 pH range and up to $40^{\circ}C$ for 6 h. The protease had a half-life of 15 days at $4^{\circ}C$, an optimum reaction time of 10 min, and an optimum substrate (casein) concentration of 0.25%. Furthermore, the Michaelis constant ($K_m$) and reaction velocity ($V_{max}$) of the protease were calculated to be 0.28% and $111.11{\mu}moles/(min{\cdot}mg)^{-1}$, respectively. The protease was stable when subjected to metal ions (2 mM), showing increased activity with most (especially $CoCl_2$ and $MgSO_4$ (30.54% increase)). It was also stable when exposed to oxidizing agents, bleaching agents, and detergents (5% v/v for 60 min). It retained 93% of its activity in non-ionic detergents (Tween-20, Tween-80, and Triton X-100). Moreover, wash performance analysis in commercial detergents (Ariel and Tide) showed that not only was the protease capable of protein stain removal, but also reduced cleaning time by 80% when added to detergents. Thus, the Serratia marcescens PPB-26 metalloprotease appears to be a promising new candidate as a laundry additive in the detergent industry.

Effect of Gamma Rays Emitted by the 99mTc on the CT Image (99mTc에서 방출되는 감마선이 CT 영상에 미치는 영향)

  • Park, Jae-Yoon;Lee, Yong-Ki
    • Journal of the Korean Society of Radiology
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    • v.13 no.2
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    • pp.169-174
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    • 2019
  • This study examines the changes that $^{99m}Tc$ causes to CT(Computed Tomography) images quantitatively when CT scans were continuously performed using $^{99m}Tc$. With the use of the CT, $^{99m}Tc$ 740MBq was injected into the Resolution Phantom and Water Phantom, and the tube voltage was changed with 80 kVp and 120 kVp, scanning before and after the injection. The result indicate, by comparing the Signal Intensity according to the presence or absence of the $^{99m}Tc$ injection with the tube voltage of 120 kVp and 80 kVp, a decrease of 0.173 and 0.241 was observed respectively and the spatial resolution increase of 0.090 and 0.109 was observed respectively. The order of the test should be considered because the gamma rays of the radiopharmaceutical used in the nuclear medicine test do not affect the CT while the effective half-life of the radiopharmaceuticals should be considered for the CT scan to reduce the influence of the gamma rays emitted after the nuclear medicine test, with the possibility to reduce the difference of the results.

Female Middle-Aged Householders' Experiences in Preparation for Old Age: With Focus on Career Female Householders (중년 여성가구주의 노후준비 경험: 직업이 있는 여성가구주를 중심으로)

Pharmacokinetics and Pharmacodynamics of Pimobendan-Pentoxifylline Liquid Mixture After Oral Administration in Dogs

  • Ro, Woong-bin;Song, Doo-won;Kim, Ki-hun;Jeong, Sang-hee;Kang, Min-hee
    • Journal of Veterinary Clinics
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    • v.36 no.3
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    • pp.159-165
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    • 2019
  • Pimobendan is an inodilator used to treat canine heart failure, and pentoxifylline is reported to be beneficial for microcirculation and heart disease. The purpose of this study was to evaluate the pharmacokinetic and pharmacodynamic profiles of a novel pimobendan-pentoxifylline liquid mixture after oral administration to dogs. Eight healthy Beagle dogs were included in the study. The dogs were divided into the control group (orally administered water; n = 4) and experimental group (orally administered pimobendan-pentoxifylline liquid mixture [pimobendan 0.25 mg/kg, pentoxifylline 15 mg/kg]; n = 4). Plasma samples were obtained and echocardiographic indices were measured for 24 hours after administration. The concentrations of pimobendan and pentoxifylline were quantified by using a liquid chromatography-mass spectrometer (LC-MS). The elimination half-life ($T_{1/2}$) was $32.96{\pm}9.80mins$ for pimobendan and $29.49{\pm}6.67mins$ for pentoxifylline. The time to reach maximum concentration ($T_{max}$) were $52.50{\pm}31.22mins$ for pimobendan and $41.25{\pm}18.87mins$ for pentoxifylline. The maximum blood concentration ($C_{max}$) was $96.92{\pm}75.64ng/mL$ for pimobendan and $7074.07{\pm}3261.1ng/mL$ for pentoxifylline. Of the echocardiographic indices, fractional shortening (FS) and left ventricular internal diameter at end systole (LVIDs) were significantly altered at 1-3 hours after the administration of pimobendan-pentoxifylline liquid mixture. The pimobendan-pentoxifylline liquid mixture was well tolerated by the dogs, with no adverse effects observed during the study.

Suppressor of Variegation 3-9 Homolog 2, a Novel Binding Protein of Translationally Controlled Tumor Protein, Regulates Cancer Cell Proliferation

  • Kim, A-Reum;Sung, Jee Young;Rho, Seung Bae;Kim, Yong-Nyun;Yoon, Kyungsil
    • Biomolecules & Therapeutics
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    • v.27 no.2
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    • pp.231-239
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    • 2019
  • Suppressor of Variegation 3-9 Homolog 2 (SUV39H2) methylates the lysine 9 residue of histone H3 and induces heterochromatin formation, resulting in transcriptional repression or silencing of target genes. SUV39H1 and SUV39H2 have a role in embryonic development, and SUV39H1 was shown to suppress cell cycle progression associated with Rb. However, the function of human SUV39H2 has not been extensively studied. We observed that forced expression of SUV39H2 decreased cell proliferation by inducing $G_1$ cell cycle arrest. In addition, SUV39H2 was degraded through the ubiquitin-proteasomal pathway. Using yeast two-hybrid screening to address the degradation mechanism and function of SUV39H2, we identified translationally controlled tumor protein (TCTP) as an SUV39H2-interacting molecule. Mapping of the interacting regions indicated that the N-terminal 60 amino acids (aa) of full-length SUV39H2 and the C-terminus of TCTP (120-172 aa) were critical for binding. The interaction of SUV39H2 and TCTP was further confirmed by co-immunoprecipitation and immunofluorescence staining for colocalization. Moreover, depletion of TCTP by RNAi led to up-regulation of SUV39H2 protein, while TCTP overexpression reduced SUV39H2 protein level. The half-life of SUV39H2 protein was significantly extended upon TCTP depletion. These results clearly indicate that TCTP negatively regulates the expression of SUV39H2 post-translationally. Furthermore, SUV39H2 induced apoptotic cell death in TCTP-knockdown cells. Taken together, we identified SUV39H2, as a novel target protein of TCTP and demonstrated that SUV39H2 regulates cell proliferation of lung cancer cells.

Daily Water Consumption and its Contribution to Calcium Intake in Korean Adults (한국 일부 성인의 수분 섭취와 수분을 통한 칼슘 섭취량 평가)

  • Park, Eun-Sun;Lee, Yeon-Kyung;Kim, Mi-Hyun;Choi, Mi-Kyeong
    • Korean Journal of Community Nutrition
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    • v.24 no.1
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    • pp.18-23
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    • 2019
  • Objectives: Although water is essential for life and can supply essential minerals, studies that evaluate calcium intake through drinking water are limited. The aim of this study was to assess calcium contents of natural mineral water (NMW) and its possible contribution to calcium intake in healthy adults. Methods: This study examined water consumption in 640 Korean adults with self-selected diet, analyzed the calcium content of 10 different brands of bottled NMWs sold in Korea, and assessed the amount of calcium intake from drinking water and its daily contribution to the recommended nutrient intake (RNI) of calcium. Results: Mean calcium content in 10 bottled NMWs was 20.9 mg/l. Daily water intakes from food composition database and calculated using energy intake based on 0.53 ml/kcal were 957.2 ml and 1109.8 ml for men and 848.3 ml and 951.6 ml for women, respectively, with a significant difference by gender (p<0.001). Daily drinking water intake was significantly higher among men than women (1203.9 ml vs. 1004.3 ml, respectively, p<0.001). Daily calcium intakes from foods were 564.0 mg for men and 534.2 mg for women. Daily possible calcium intakes from drinking bottled water were 25.2 mg for men and 21.0 mg for women (p<0.001). The contribution of daily calcium intake from drinking bottled water to RNI of calcium was 3.3% for men and 2.9% for women without significant difference. Conclusions: One half of the daily total water intake was consumed as drinking water, and possible calcium intake through drinking water was about 3% of RNI.

Cesium removal in water using magnetic materials ; A review (자성체 물질을 이용한 수중의 세슘제거 동향)

  • Yeo, Wooseok;Cho, Byungrae;Kim, Jong Kyu
    • Journal of the Korean Society of Industry Convergence
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    • v.21 no.6
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    • pp.395-408
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    • 2018
  • Even after the Fukushima nuclear accident in 2011, the rate of production of electric energy using nuclear energy is increasing, but there is a great danger such as the radioactive waste produced when using nuclear power, the catastrophic accident of nuclear power plant, and connection with nuclear weapons. In particular, Cs present in the ionic form of alkaline elements has a long half-life (30.17 years) because it is readily absorbed by the organism and emits intense gamma rays, thus presenting a serious radiation hazard. Therefore, it must be completely removed before it can be released into the natural ecosystem, because it can adversely affect not only humans but also natural ecosystems. Many adsorbents and ion exchangers which have high Cs removal efficiency have been used in recent years to completely separate and remove by self separation in water. Many adsorbents and ion exchangers which have high Cs removal efficiency have been used in recent years to completely separate and remove by self separation in water. In addition, researches have been doing to synthesize magnetic materials with adsorbents such as HCF and PB, and it shows a great effect in the removal rate of Cs present in wastewater or the maximum Cs adsorption amount. In particular, when a magnetic material was applied, excellent results were obtained in which only Cs was selectively removed from other cations. However, new problems such as applicability in the sea where Cs is directly released, applicability in various pH ranges, and failure to preserve the magnetizing force possessed by the magnetic body have been found. However, researches using ferromagnetic field with stronger magnetic properties than those of magnetic bodies is considered to be insufficient. Therefore, it is considered that if the researches combining the ferromagnetic field with the magnetization ability and functional adsorbents more actively, the radioactive material Cs which adversely affects the natural ecosystem can be effectively removed.

Inventory Estimation of 36Cl and 41Ca in Concrete of Kori Unit 1 (고리 1호기의 콘크리트 내 36Cl 및 41Ca의 방사화재고량 평가)

  • Jang, Mee;Lim, Jong Myoung;Kim, Hyun Chul;Kim, Chang-Jong
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.1
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    • pp.121-126
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    • 2019
  • The radionuclide inventory prediction of a nuclear power plant can help establish decommissioning plan by providing information of radiation environment. Accumulated radionuclides in reactors and related facilities after reactor shutdown can be divided into neutron activated materials and contaminated materials. Among the neutron activated radionuclides, $^{36}Cl$ and $^{41}Ca$ are important from the viewpoint of disposal because of its long half-life and physiochemical characteristics. In this research, we calculated the radionuclides of $^{36}Cl$ and $^{41}Ca$ in bioshielding concrete by estimating the neutron flux and cross section using the MCNPX. And we evaluated the inventories of $^{36}Cl$ and $^{41}Ca$ using the activation calculation code ORIGEN2.

Shift in benthic diatom community structure and salinity thresholds in a hypersaline environment of solar saltern, Korea

  • Bae, Hanna;Park, Jinsoon;Ahn, Hyojin;Khim, Jong Seong
    • ALGAE
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    • v.35 no.4
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    • pp.361-373
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    • 2020
  • The community dynamics of benthic diatoms in the hypersaline environment are investigated to advance our understanding how salinity impacts marine life. Diatoms were sampled in the two salterns encompassing salt Ponds, ditches, and seawater reservoirs (n = 11), along the salinity gradient (max = 324 psu), and nearby tidal flats (n = 2). The floral assemblages and distributions across sites and stations showed great variations, with a total of 169 identified taxa. First, not surprisingly, higher diversity of benthic diatoms was found at natural tidal flats than salterns. The saltern diatoms generally showed salinity dependent distributions with distinct spatial changes in species composition and dominant taxa. Biota-environment and principal component analysis confirmed that salinity, mud content, and total nitrogen were key factors influencing the overall benthic community structure. Some dominant species, e.g., Nitzschia scalpelliformis and Achnanthes sp. 1, showed salinity tolerance / preference. The number of diatom species at salinity of >100 psu reduced over half and no diatoms were found at maximum salinity of 324 psu. The highest salinity for the observed live diatoms was 205 psu, however, a simple regression indicated a theoretical salinity threshold of ~300 psu on the survival. Finally, the indicator species were identified along the salinity gradient in salterns as well as natural tidal flats. Overall, high species numbers, varying taxa, and euryhaline distributions of saltern diatoms collectively reflected a dynamic saltern ecosystem. The present study would provide backgrounds for biodiversity monitoring of ecologically important microalgal producers in some unique hypersaline environment, and elsewhere.