• Toxicological Research
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• v.32 no.4
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• pp.353-358
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• 2016

The generation and collection of cigarette smoke (CS) is a prerequisite for any toxicology study on smoking, especially an in vitro CS exposure study. In this study, the effects on blood and vascular function were tested with two widely used CS preparations to compare the biological effects of CS with respect to the CS preparation used. CS was prepared in the form of total particulate matter (TPM), which is CS trapped in a Cambridge filter pad, and cigarette smoke extract (CSE), which is CS trapped in phosphate-buffered saline. TPM potentiated platelet reactivity to thrombin and thus increased aggregation at a concentration of $25{\sim}100{\mu}g/mL$, whereas 2.5~10% CSE decreased platelet aggregation by thrombin. Both TPM and CSE inhibited vascular contraction by phenylephrine at $50{\sim}100{\mu}g/mL$ and 10%, respectively. TPM inhibited acetylcholine-induced vasorelaxation at $10{\sim}100{\mu}g/mL$, but CSE exhibited a minimal effect on relaxation at the concentration that affects vasoconstriction. Neither TPM nor CSE induced hemolysis of erythrocytes or influenced plasma coagulation, as assessed by prothrombin time (PT) and activated partial thromboplastin time (aPTT). Taken together, CS affects platelet activity and deteriorates vasomotor functions in vitro. However, the effect on blood and blood vessels may vary depending on the CS preparation. Therefore, the results of experiments conducted with CS preparations should be interpreted with caution.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.433-440
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• 2023

High dose rate brachytherapy is a cancer treatment that intensively irradiates radiation to tumors by inserting isotopes with high dose rates into the body. For such a treatment, it is necessary to deliver an accurate dose to the tumor tissue through an accurate treatment plan while delivering only a minimum dose to the normal tissue. Therefore, it is very important to check the location accuracy of the source through accurate Quality Assurance (QA) in clinical practice. However, since the source position is determined using a ruler, automatic radiographer, video monitor, etc. in clinical practice, it yields inaccurate results. In this study, a semiconductor dosimeter using CsPbI₂Br and CsPbIBr₂ was fabricated. And, in order to analyze whether it is more suitable for the relative QA dosimeter for brachytherapy device among the two materials, the radiation detection ability of each was compared and evaluated. In order to evaluate the radiation detection ability in brachytherapy, the reproducibility and linearity of the two materials were evaluated in ¹⁹²IR. In the reproducibility evaluation, CsPbI₂Br presented a Relative Standard Deviatio(RSD) of 0.98% and CsPbIBr₂ presented an RSD of 3.45%. In the linearity evaluation, the coefficient of determination (R²) of CsPbI₂Br was presented as 0.9998, and the R² of CsPbIBr₂ was presented as 0.9994. As a result of the evaluation, it was found that CsPbI₂Br was more stable in radiation detection while satisfying the evaluation criteria in the dosimeter manufactured in this experiment. Therefore, CsPbI₂Br material is suitable for application as a relative dosimeter for radiation detection in brachytherapy devices.

• Journal of Electrochemical Science and Technology
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• v.14 no.4
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• pp.303-310
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• 2023

Microbial fuel cells (MFCs) are a bioelectrochemical system where electrochemically active bacteria convert organic waste into electricity. Poly(vinyl alcohol) (PVA) and chitosan (CS) are polymers that have been studied as potential alternative ion exchange membranes to Nafion for many electrochemical systems. This study examined the optimal mixing ratio of PVA and chitosan CS in a PVA:CS composite membrane for MFC applications. PVA:CS composite membranes with 1:1, 2:1, and 3:1 ratios were synthesized and tested. The water uptake and ion exchange capacity, Fourier transform infrared spectra, and scanning electron microscopy images were analyzed to determine the physicochemical properties of PVA:CS membranes. The prepared membranes were applied to the ion exchange membrane of the MFC system, and their effects on the electrochemical performance were evaluated. These results showed that the composite membrane with a 3:1 (PVA:CS) ratio showed comparable performance to the commercialized Nafion membrane and produced more electricity than the other synthesized membranes. The PVA:CS membrane implemented MFCs produced a maximum power density of 0.026 mW cm^-2 from organic waste with stable performance. Therefore, it can be applied to a cost-effective MFC system.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.285-291
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• 2008

A potential probiotics bacterial strain, CS90, was isolated from Korean soybean paste (doenjang). The strain CS90 showed antimicrobial activity against food-borne pathogenic bacteria including Salmonella enterica, Salmonella enteritids, Salmonella typhymurium, Bacillus cereus, Listeria ivanovii, Listeria. monocytogenes, Sthaphylococcus aureus, and Sthaphylococcus epidermidis and showed a significant survival rate of 35.7 to 57.8% under the artificial gastric acidic condition (pH 2 to 3). The strain CS90 was classified as Bacillus subtilis based on morphological, physiological, chemotaxonomic features and phylogenetic analysis based on 16S rDNA sequence and designated as B. subtilis CS90. B. subtilis CS90 can be used as a potential probiotics.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.196-196
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• 2017

Oilseed crop Camelina (Camelina sativa L.) is a suitable for biodiesel production that has high adaptability under low-nutrient condition like marginal land and requires low-input cost for cultivation. Enhanced abiotic stress tolerance of Camelina is very important for oil production under the wide range of different climate. CsRCI2s (Rare Cold Inducible 2) are related proteins in various abiotic stresses that predicted to localized at plasma membrane (PM) and endoplasmic reticulum (ER). These proteins are consist of eight-family that can be divided into tail (CsRCI2D/E/F/G) and no-tail (CsRCI2A/B/E/H) type of C-terminal. However, it is still less understood the function of C-terminal tail. In this study, CsRCI2D/H genes were cloned through gateway cloning system that used pCB302-3 as destination vector. And we used agrobacterium-mediated transformation system for generation of overexpression (OX) transformants. Overexpression of target gene was confirmed using RT-PCR and segregation ratio on selection media. We analyzed physiological response in media and soil under abiotic stresses using CsRCI2D and CsRCI2H overexpression plant. To compare abiotic stresses tolerance, wild type and CsRCI2D/H OX line seeds were sown on agar plate treated with various NaCl and mannitol concentration for 7 days. In the test of growth rate under abiotic stress on media, CsRCI2H OX line showed similar to NaCl and mannitol stress. In the other hand, CsRCI2D OX line showed to be improved stress tolerance that especially increased in 200mM NaCl but was similar on mannitol media. In greenhouse, WT and CsRCI2D/H OX lines for physiological analysis and productivity under abiotic stresses were treated 100, 150, 200mM NaCl. Then it was measured various parameters such as leaf width and length, plant height, total seed weight, flower number, seed number. CsRCI2H OX line in greenhouse did not show any changes in physiological parameters but CsRCI2D OX line was improved both physiological response and productivity under NaCl stress. Among physiological parameters of CsRCI2D OX line under NaCl stress, leaf length and width were observed shorter than WT but it were slightly longer than WT in 200mM NaCl stress. Furthermore, total seed weight of CsRCI2D OX line under stress displayed to decrease than WT in normal condition, but it was gradually raised with increasing NaCl stress then more than WT relatively. These results suggested CsRCI2D might be contribute to improve abiotic stress tolerance. However, function of CsRCI2H is need to more detail study. In conclusion, overexpression of CsRCI2s family can generate various environmental stress tolerance plant and may improve crop productivity for bio-energy production.

• The Journal of Dong Guk Oriental Medicine
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• v.6 no.2
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• pp.99-107
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• 1998

Cyclosporin A(CsA) is a selective immunosuppressive agent that has been credited with improved survival of solid organ allografts. Lymph node of BALB/C mouse administered CsA immunohistochemically observed to understand immunosuppressive effects of CsA on T lymphocytes, IL-2 receptors, and natural killer NK cells in lymph node. CsA orally administered daily for 10days at the dose 45mg/kg/day/. The lymph node were obtained at day 3, 7, and 14 after CsA administration and embedded with paraffin, and then stained by following ABC method that used monoclonal antibody including L3T4(CD4), Ly2(CD8), IL-2R(CD25), and NK-1.1(CD56). There were little changes of reactive degree and number of helper T lymphocytes, cytotoxic T lymphocytes, IL-2 receptors, and NK cells at day 3 after CsA administration, but they began to decrease at day 7. These decrease were greatest at day 14. The helper T lymphocytes. cytotoxic T lymphocytes, IL-2 receptors, and NK cells distributed in paracortex and medullary sinus. These results indicated that the secretion of IL-2 began to decrease at day 7 after CsA administration and subsequently to suppress T lymphocytes and NK cell as components of cell-mediated immunity.

• Economic and Environmental Geology
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• v.53 no.5
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• pp.529-542
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• 2020

The cesium (Cs) sorption characteristics of a bead-type polysulfone carrier contained HNO₃-treated bamboo charcoal (3 - 5 mm in diameter) in water system were investigated and its Cs removal efficiency as an adsorbent from water was also identified by various laboratory experiments. From the results of batch sorption experiments, the bead-type polysulfone carrier with only 5% HNO₃-treated bamboo charcoal (P-5NBC) represented the high Cs removal efficiency of 57.8% for 1 hour sorption time. The Cs removal efficiency of P-5NBC in water after 24 hours reaction maintained > 69% at a wide range of pH and temperature conditions, attesting to its applicability under various water systems. Batch sorption experiments were repeated for P-5NBC coated with two cultivated microorganisms (Pseudomonas fluorescens and Bacillus drentensis), which were typical indigenous species inhabited in soil and groundwater. The Cs removal efficiency for two microorganisms coated polysulfone carrier (BP-5NBC) additionally increased by 19% and 18%, respectively, compared to that of only P-5NBC without microorganisms coated. The average Cs desorption rate of P-5NBC for 24 h was lower than 16%, showing the Cs was stably attached on HNO₃-treated bamboo charcoal in so much as its long-term use. The maximum Cs sorption capacity (q_m) of P-5NBC calculated from the Langmuir isotherm model study was 60.9 mg/g, which was much higher than those of other adsorbents from previous studies for 1 h sorption time. The results of continuous column experiments showed that the P-5NBC coated with microorganisms packed in the column maintained > 80% of the Cs removal efficiency during 100 pore volumes flushing. It suggested that only 14.7 g of P-5NBC (only 0.75 g of HNO₃ treated bamboo charcoal included) can successfully clean-up 7.2 L of Cs contaminated water (the initial Cs concentration: 1 mg/L; the effluent concentration: < 0.2 mg/L). The present results suggested that the Cs contaminated water can be successfully cleaned up by using a small amount of the polysulfone carrier with HNO₃-treated bamboo charcoal.

• Korean Journal of Materials Research
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• v.33 no.8
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• pp.344-351
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• 2023

Cesium lead iodide (CsPbI₃) with a bandgap of ~1.7 eV is an attractive material for use as a wide-gap perovskite in tandem perovskite solar cells due to its single halide component, which is capable of inhibiting halide segregation. However, phase transition into a photo inactive δ-CsPbI₃ at room temperature significantly hinders performance and stability. Thus, maintaining the photo-active phase is a key challenge because it determines the reliability of the tandem device. The dimethylammonium (DMA)-facilitated CsPbI₃, widely used to fabricate CsPbI₃, exhibits different phase transition behaviors than pure CsPbI₃. Here, we experimentally investigated the phase behavior of DMA-facilitated CsPbI₃ when exposed to external factors, such as heat and moisture. In DMA-facilitated CsPbI₃ films, the phase transition involving degradation was observed to begin at a temperature of 150 ℃ and a relative humidity of 65 %, which is presumed to be related to the sublimation of DMA. Forming a closed system to inhibit the sublimation of DMA significantly improved the phase transition under the same conditions. These results indicate that management of DMA is a crucial factor in maintaining the photo-active phase and implies that when employing DMA designs are necessary to ensure phase stability in DMA-facilitated CsPbI₃ devices.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.399-406
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• 2004

본 연구에서는 국내 원전이 위치한 지역의 토양에서 $Cs^{137}$의 축적 경향을 파악하기 위하여 원전이 위치한 영광군 관내의 평지와 고산지대인 금정산, 불갑산 및 영광원전으로부터 원거리에 위치한 내장산 등을 대상으로 토양 중 $Cs^{137}$의 화학적인 특성과 고도에 따른 $Cs^{137}$의 축적 경향을 평가하기 위하여 실험을 통한 연구를 수행하였다. 일반적으로 국내 토양 중 $Cs^{137}$의 농도는 불검출 - 2523q/kg-dry의 범위 내에 포함되었으며 본 연구에서 수행한 평지부분과 고산지대인 원전으로부터 2km 떨어진 금정산, 약 20km 떨어진 불갑산 및 원거리에 위치한 내장산에서도 지금까지의 $Cs^{137}$ 농도 범위에 들었다. 그러나 고산지대는 평지에서와는 다르게 고도가 증가함에 따라 $Cs^{137}$ 농도도 증가하는 경향을 보이고 있고, 정상 부분보다 $Cs^{137}$의 농도가 하부 부분보다 더 높게 나타났고 영광원전 인근 일반평지부분보다는 $Cs^{137}$의 방사능 농도가 2~6배 정도의 높은 경향을 나타내었다. 연구결과 $Cs^{137}$의 분포는 지형적 요인(고도, 강수량 등)과 토양의 화학적 요인(양이온치환용량)과 상관성이 근 것으로 나타났다. 지형적 요인으로는 주로 고도를 들수가 있는데 높은 고도의 산의 경우 대기중 $Cs^{137}$이 토양에 침투되는 기회가 커짐으로 동일한 토질 조건의 평지 토양에 비해 높은 $Cs^{137}$ 준위를 나타내었다. 토양의 화학적 요인으로는 양이온치환용량이 주요 인자임이 규명되었다. 양이온치환용량은 침적된 $Cs^{137}$을 토양에 고정시키는 능력을 나타내며 같은 지형조건에서 높은 양이온치환용량을 가진 시료가 낮은 양이온치환용량을 가진 토양에 비해 $Cs^{137}$ 농도가 높은 값을 보였다.

• Journal of The Korean Association of Information Education
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• v.24 no.4
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• pp.301-311
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• 2020

A model of cooperative learning, Pair Programming was applied to regular class for middle school students. Algorithm and programming skill were taught through the pair programming for two week and the achievement was analyzed based on 4Cs(Critical thinking, Communication, Collaboration, Creativity) proposed by the NEA(National Education Association). The control group was statistically significant on Critical Thinking between pre-test and post-test1, while the experimental group was statistically significant on all measurements of 4Cs. Between pre-test and post-test2, the control group showed overall little difference in range of 0.2 points on the 4Cs average scores. while the experimental group was statistically significant on all measurements of 4Cs. Between post-test1 and post-test2, there was no significant difference on 4Cs average scores in both groups. The experimental group showed higher score results on all 4Cs than the control group. This study verifies that the benefits of Pair Programming on 4Cs.