• Title/Summary/Keyword: Time-Dependent Degradation

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The Causes of Deforestation and Loss of Genetic Resources in Bangladesh

  • Islam, Mohammad Saiful;Islam, Mohammad Jahidul;Ahmed, Sheikh Ali;Chun, Su-Kyoung;Chong, Song-Ho;Kim, Jong-In
    • Journal of the Korea Furniture Society
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    • v.18 no.4
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    • pp.317-323
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    • 2007
  • Almost all the people, particularly the rural people are directly dependent on the continued productivity of natural resources, like water, soils, forests and fisheries. But the overuse by the extremely high population pressures has degraded the natural resources into severe widespread deforestation. The degradation of natural resources, particularly the plant resources has been a great concern for socio-economic and sustainable development of the country. The Forests in Bangladesh have been depleted and degraded in volume, area, and quantity, thus requiring urgent forest protection by identifying the causes of forest loss. There are so many causes of deforestation and loss of genetic resources such as; the timber industry, which, legal or not, are cutting too many trees; indigenous forest dwellers, having their own types of problems; migrants, who, because of problems in their places of origin, have decided to move to the forests and the government through its Forest Department which is not able or willing to implement suitable policies to regulate the cutting trees and to prevent illegal cutting. Because it is a time consuming task to mitigate the first and second sets of factors, we recommend involving forest dwellers in forestry practices as much as possible and taking necessary steps to alleviate the third and fourth sets and thereby reduce the rate of forest depletion. Accordingly, a number of strategies that should be adopted to halt the loss of remaining forest cover are discussed.

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Studies on the compound spun silk and its fabrics (복합견방사 및 그 제품개발에 관한 연구)

  • 남중희;송기언
    • Journal of Sericultural and Entomological Science
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    • v.18 no.1
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    • pp.27-39
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    • 1976
  • In this study several kinds of spun silk yarn-synthetic filament compounded yarn was manufactured, and several fabrics woven from above mentioned silk compound yarn for evaluation of serviceability as clothing materials. The following results were obtained: 1. Degumming agents are in the order of sodium silicate, sodium hydroxide, sodium carbornate, soap and water. 2. When the concentration of sodium hydroxide is exceeded 3%, degradation of floss silk property is resulted because of excessive dissolving out of silk protein. 3. Degumming effect is much improved by concentration of degumming agent and less by its treating time. 4. Simultaneous application of more the 2 kinds of degumming agent is desirable for improvement of floss silk. 5. Application of natural organic acid brings very good results in keeping original scooping and color of the silk. 6. Load and elongation it increased by compound with synthetic filament yarn. 7. Even the evenness of compound yarn is largely dependent on the quality of floss silk and extent of degumming, the C.V.% of silk compound yarn in the experiment was 8-12%. 8. Single bath dyeing technique was impossible for their cloth, and dyeing was performed in 2 bath system separately for silk and synthetic fiber. 9. Shrinkage ratio due to the dyeing of fabric was 23% in case of polyester and spun silk fabric. 10. The final woven cloth can be applicable to (a) Blouse in care of thin cloth (compound silk fabric) (b) Korean costume for women in case of thick cloth. (compound hand spun silk fabric)

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Induction of ER Stress-Mediated Apoptosis by ${\alpha}$-Lipoic Acid in A549 Cell Lines

  • Kim, Jong-In;Cho, Sung-Rae;Lee, Chang-Min;Park, Eok-Sung;Kim, Ki-Nyun;Kim, Hyung-Chul;Lee, Hae-Young
    • Journal of Chest Surgery
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    • v.45 no.1
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    • pp.1-10
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    • 2012
  • Background: ${\alpha}$-Lipoic acid (${\alpha}$-LA) has been studied as an anticancer agent as well as a therapeutic agent for diabetes and obesity. We performed this study to evaluate the anticancer effects and mechanisms of ${\alpha}$-LA in a lung cancer cell line, A549. Materials and Methods: ${\alpha}$-LA-induced apoptosis of A549 cells was detected by fluorescence-activated cell sorting analysis and a DNA fragmentation assay. Expression of apoptosis-related genes was analyzed by western blot and reverse transcription.polymerase chain reaction analyses. Results: ${\alpha}$-LA induced apoptosis and DNA fragmentation in A549 cells in a dose- and time-dependent manner. ${\alpha}$-LA increased caspase activity and the degradation of poly (ADP-ribose) polymerase. It induced expression of endoplasmic reticulum (ER) stress-related genes, such as glucose-regulated protein 78, C/EBP-homologous protein, and the short form of X-box binding protein-1, and decreased expression of the anti-apoptotic protein, X-linked inhibitor of apoptosis protein. Reactive oxygen species (ROS) production was induced by ${\alpha}$-LA, and the antioxidant N-acetyl-L-cysteine decreased the ${\alpha}$-LA-induced increase in expression of apoptosis and ER stress-related proteins. Conclusion: ${\alpha}$-LA induced ER stress-mediated apoptosis in A549 cells via ROS. ${\alpha}$-LA may therefore be clinically useful for treating lung cancer.

The Evaluation for Reliability Characteristics of MOS Devices with Different Gate Materials by Plasma Etching Process (게이트 물질을 달리한 MOS소자의 플라즈마 피해에 대한 신뢰도 특성 분석)

  • 윤재석
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.2
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    • pp.297-305
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    • 2000
  • It is observed that the initial properties and degradation characteristics on plasma of n/p-MOSFET with polycide and poly-Si as different gate materials under F-N stress and hot electron stress are affected by metal AR(Antenna Ratio) during plasma process. Compared to that of MOS devices with poly-Si gate material, reliability properties on plasma of MOS devices with polycide gate material are improved. This can be explained by that fluorine of tungsten polycide process diffuses through poly-Si into gate oxide and results in additional oxide thickness. The fact that MOS devices with polycide gate material can reduce damages of plasma process shows possibility that polycide gate material can be used as gate material for next generation MOS devices.

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Role of Retinoic Acid in Spontaneous Apoptosis of Human Neutrophils

  • Yang, Eun-Ju;Lee, Ji-Sook;Kim, Dong-Hee;Min, Bok-Kee;Hyun, Sung-Hee;Kim, In-Sik
    • Biomedical Science Letters
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    • v.13 no.4
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    • pp.279-285
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    • 2007
  • Although retinoic acid has been known as either anti-inflammatory or pro-inflammatory molecule, depending on the cell type, its exact role in mature human neutrophils has not been fully explored. In this study, we investigate the effects of retinoic acid on neutrophil apoptosis and the associated mechanism and found that 9-cis retinoic acid (9CRA) significantly inhibits the spontaneous apoptosis of neutrophils. Its effect is increased by co-treatment with $TNF-\alpha$ (P<0.05). The 9CRA-induced inhibition is blocked by the following enzyme inhibitors: Ly 294002, phosphoinoside (PI)-3 kinase inhibitor, U73122, a phospholipase C (PLC) inhibitor, PP2, Src family protein inhibitor, SB202190, p38 MAPK inhibitor, and BAY-11-7085, NF-kB inhibitor. This study also demonstrates that all-trans retinoic acid suppresses spontaneous apoptosis, similar to the mechanism of inhibition exhibited by 9CRA. Phosphorylation of p38 MAPK decreases by 9CRA treatment. $Ik-B{\alpha}$ is degraded until 30 minutes after a time-dependent 9CRA treatment, but degradation can be inhibited by Ly 294002. These results indicate that 9CRA decreases p38 MAPK activation, induces NF-kB activation via PI-3 kinase, and also blocks cleavage of caspase 3. As these findings suggest, 9CRA has a molecular mechanism which may help pro-inflammatory response by blocking neutrophil apoptosis.

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Decomposition characteristics of pollutants by time dependent variation of livestock carcass leachate (매몰지 침출수의 경시변화에 따른 오염물질 분해특성)

  • Kim, Yong Jun;Kang, Young Yeul;Hwang, Dong Gun;Jeon, Tae Wan;Shin, Sun Kyoung
    • Analytical Science and Technology
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    • v.30 no.6
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    • pp.338-347
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    • 2017
  • The purpose of this study is to investigation of the decomposition characteristics in a pilot-scale burial site of livestock in three kinds of typical soils in Korea: sandy loam soil, clay loam soil, and sandy soil. In this study, we confirmed that most of the animals in the condition were decomposed within three years as mentioned in the "Livestock burial regional environmental research guidelines." We also determined that the decomposition rate of dead cows was higher than that of dead pigs, and that the biodegradation rate depends on the soil types in the following order: sandy soil > clay loam soil > sandy loam soil. The various external environment factors, such as temperature, moisture, pH, earthiness, nutrient, and the burial depth, should be managed properly for appropriate decomposition of dead animals.

Apoptotic Effects and Mechanism Study of Silymarin in DU145 Cells (전립선 암세포에서 silymarin의 고사 유도 효과 및 기전 연구)

  • Kwon Kang-Beom;Kim Eun-Kyung;Park Sung-Joo;Song Ho-Joon;Lee Young-Rae;Park Byung-Hyun;Park Jin-Wzoo;Ryu Do-Gon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.6
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    • pp.1552-1556
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    • 2005
  • Silymarin has been known to exert anti-tumoral activity in Korea. However, its molecular mechanism of action is not understood. In this study, we found that silymarin induced apoptosis in androgen-independent prostate cancer DU145 cells as confirmed by DNA fragmentation. Our data demonstrated that silymarin-induced apoptotic cell death was accompanied by activation of caspase-3 and subsequent cleavages of its substrates, poly(ADP-ribose) polymerase (PARP) in a time- and concentration-dependent manner. Also, silymarin-induced apoptotic mechanism of DU145 cells involved the induction of Par-4 protein expression. Taken together, these results suggest that silymarin induces the activation of caspase-3, degradation of PARP, increase of Par-4 expression, and eventually leads to apoptotic cell death.

Traffic Data Generation Technique for Improving Network Attack Detection Using Deep Learning (네트워크 공격 탐지 성능향상을 위한 딥러닝을 이용한 트래픽 데이터 생성 연구)

  • Lee, Wooho;Hahm, Jaegyoon;Jung, Hyun Mi;Jeong, Kimoon
    • Journal of the Korea Convergence Society
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    • v.10 no.11
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    • pp.1-7
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    • 2019
  • Recently, various approaches to detect network attacks using machine learning have been studied and are being applied to detect new attacks and to increase precision. However, the machine learning method is dependent on feature extraction and takes a long time and complexity. It also has limitation of performace due to learning data imbalance. In this study, we propose a method to solve the degradation of classification performance due to imbalance of learning data among the limit points of detection system. To do this, we generate data using Generative Adversarial Networks (GANs) and propose a classification method using Convolutional Neural Networks (CNNs). Through this approach, we can confirm that the accuracy is improved when applied to the NSL-KDD and UNSW-NB15 datasets.

Efficient Elimination of Tetracycline by Ferrate (VI): Real Water Implications

  • Levia Lalthazuala;Lalhmunsiama Lalhmunsiama;Ngainunsiami Ngainunsiami;Diwakar Tiwari;Seung Mok Lee;Suk Soon Choi
    • Applied Chemistry for Engineering
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    • v.34 no.3
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    • pp.318-325
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    • 2023
  • The detection of antibiotics in treated wastewater is a global concern as it enters water bodies and causes the development of antibiotic resistance genes in humans and marine life. The study specifically aims to explore the potential of ferrate (VI) in eliminating tetracycline (TCL). The degradation of TCL is optimized with parametric studies, viz., the effect of pH and concentration, which provide insights into TCL elimination. The increase in pH (from 7.0 to 10.0) favors the percentage removal of TCL; however, the increase in TCL concentrations from 0.02 to 0.3 mmol/L caused a decrease in percentage TCL removal from 97.4 to 29.1%, respectively, at pH 10.0. The time-dependent elimination of TCL using ferrate (VI) followed pseudosecond-order rate kinetics, and an apparent rate constant (kapp) was found at 1978.8 L2 /mol2 /min. Coexisting ions, i.e., NaNO3, Na2HPO4, NaCl, and oxalic acid, negligibly affect the oxidation of TCL by ferrate (VI). However, EDTA and glycine significantly inhibited the elimination of TCL using ferrate (VI). The mineralization of TCL using ferrate (VI) was favored at higher pH, and it increased from 18.57 to 32.52% when the solution pH increased from pH 7.0 to 10.0. Additionally, the real water samples containing a relatively high level of inorganic carbon spiked with TCL revealed that ferrate (VI) performance in the removal of TCL was unaffected, which further inferred the potential of ferrate (VI) in real implications.

Deep learning-based LSTM model for prediction of long-term piezoresistive sensing performance of cement-based sensors incorporating multi-walled carbon nanotube

  • Jang, Daeik;Bang, Jinho;Yoon, H.N.;Seo, Joonho;Jung, Jongwon;Jang, Jeong Gook;Yang, Beomjoo
    • Computers and Concrete
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    • v.30 no.5
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    • pp.301-310
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    • 2022
  • Cement-based sensors have been widely used as structural health monitoring systems, however, their long-term sensing performance have not actively investigated. In this study, a deep learning-based methodology is adopted to predict the long-term piezoresistive properties of cement-based sensors. Samples with different multi-walled carbon nanotube contents (0.1, 0.3, and 0.5 wt.%) are fabricated, and piezoresistive tests are conducted over 10,000 loading cycles to obtain the training data. Time-dependent degradation is predicted using a modified long short-term memory (LSTM) model. The effects of different model variables including the amount of training data, number of epochs, and dropout ratio on the accuracy of predictions are analyzed. Finally, the effectiveness of the proposed approach is evaluated by comparing the predictions for long-term piezoresistive sensing performance with untrained experimental data. A sensitivity of 6% is experimentally examined in the sample containing 0.1 wt.% of MWCNTs, and predictions with accuracy up to 98% are found using the proposed LSTM model. Based on the experimental results, the proposed model is expected to be applied in the structural health monitoring systems to predict their long-term piezoresistice sensing performances during their service life.