• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.49-58
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• 2006

Recently, geosynthetic clay liners (GCLs) have increasingly been used to replace compacted clay liners (CCLs) in composite liner systems. Since the introduction of GCLs to waste containment facilities, one of the major concerns about their use has been the hydraulic equivalency to CCLs as required by regulations. Laboratory test results and more recently field observations show that the thickness, or mass per unit area, of hydrated bentonite in a GCL can decrease under normal stress, especially around zones of stress concentration or nonuniform stresses, such as a rock or roughness in the subgrade, a leachate sump, or wrinkles in an overlying geomembrane. This paper presents field case histories that confirm the laboratory observations of bentonite migration and the effect of bentonite migration on hydraulic equivalency and contaminant transport through a GCL.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1991.05a
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• pp.8-12
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• 1991

Biodegradation of carbon tetrachloride (CTC) in denitrifying and aerobic columns was investigated under various conditions of electron-acceptor and electron-donor availability. CTC removal increased when the electron-acceptor (nitrate) injection was stopped in the denitrifying column ; however, CTC removal decreased when electron donor (acetate) was deleted in the denitrifying and the aerobic column. Small fractions of the CTC removed appeared as chloroform, indicating that reductive dechlorination of CTC was occurring. The results from the denitrifying column support the hypothesis that CTC behave as an electron acceptor that competes for the pool of available electrons inside the bacterial cells.

• Korean Journal of Pharmacognosy
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• v.20 no.3
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• pp.196-203
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• 1989

Experimental studies were conducted to investigate the effect of Sagan-Tang on analgesic, sedative, antipyretic, isolated ileum and blood vessel and so on. The results of this investigation were summarized as follows; Analgesic action by the acetic acid stimulating method in mice were recognized. Prolonging action against the hypnotic duration induced by thiopental-Na was noted in mice. Antipyretic effect in typhoid vaccine febrile rats was recognized. Spontaneous motility of the isolated ileum of mice was suppressed and contractions of the isolated ileum of mice and guinea-pig induced by accetylcholine chloride, barium chloride and histamine were remarkably inhibited. Vaso-diating and hypotensive actions were recognized in rabbits. GOT and GPT activities in the serum of rats damaged by $CCl_4$ and galactosamine were decreased remarkably.

• Computers and Concrete
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• v.22 no.6
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• pp.551-561
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• 2018

The percolation of interfacial transition zone (ITZ) in cementitious materials is of great importance to the transport properties and durability issues. This paper presents numerical simulation research on the ITZ percolation threshold of mortar specimens at meso-scale. To simulate the meso-scale model of mortar as realistically as possible, the aggregates are simplified as ellipsoids with arbitrary orientations. Major and minor aspect ratios are defined to represent the global shape characteristics of aggregates. Some algorithms such as the burning algorithm, Dijkstra's algorithm and Connected-Component Labeling (CCL) algorithm are adopted for identification of connected ITZ clusters and percolation detection. The effects of gradation and aspect ratios of aggregates on ITZ percolation threshold are quantitatively studied. The results show that (1) the ITZ percolation threshold is mainly affected by the specific surface area (SSA) of aggregates and shows a global decreasing tendency with an increasing SSA; (2) elongated ellipsoidal particles can effectively bridge isolated ITZ clusters and thus lower the ITZ percolation threshold; (3) as ITZ volume fraction increases, the bridging effect of elongated particles will be less significant, and has only a minor effect on ITZ percolation threshold; (4) it is the ITZ connectivity that is essentially responsible for ITZ percolation threshold, while other factors such as SSA and ITZ volume fraction are only the superficial reasons.

• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.324-332
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• 2022

The incidence of stress-related type 2 diabetes (stress-T2D), which is aggravated by physiological stress, is increasing annually. The effects of Lactobacillus, a key component of probiotics, have been widely studied in diabetes; however, studies on the effects of postbiotics are still limited. Here, we aimed to examine the mechanism through which heat-killed Lactiplantibacillus plantarum LRCC5314 (HK-LRCC5314) alleviates stress-T2D in a cold-induced stress-T2D C57BL/6 mouse model. HK-LRCC5314 markedly decreased body weight gain, adipose tissue (neck, subcutaneous, and epididymal) weight, and fasting glucose levels. In the adipose tissue, mRNA expression levels of stress-T2D associated factors (NPY, Y2R, GLUT4, adiponectin, and leptin) and pro-inflammatory factors (TNF-α, IL-6, and CCL-2) were also altered. Furthermore, HK-LRCC5314 increased the abundance of Barnesiella, Alistipes, and butyrate-producing bacteria, including Akkermansia, in feces and decreased the abundance of Ruminococcus, Dorea, and Clostridium. Thus, these findings suggest that HK-LRCC5314 exerts protective effects against stress-T2D via gut microbiome modulation, suggesting its potential as a supplement for managing stress-T2D.

• Analytical Science and Technology
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• v.19 no.5
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• pp.376-382
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• 2006

In this work, pitch/activated carbon/$TiO_2$ composite were prepared by $CCl_4$ solvent method with different mixing ratios. The BET surface area of pitch/activated carbon/$TiO_2$ composite has a significantly increase with increasing activated carbon content in pitch/activated carbon/$TiO_2$ composite. The surface structure and elemental compositions of the composite were studied by SEM and EDX, respectively. The SEM results were presented to the characterization of porous texture on the pitch/activated carbon/$TiO_2$ composite. And EDX data was shown the presence of C, O, S, Ti and other elements. The structural properties of the composite were studied in XRD measurements. The $TiO_2$ crystal phases of the pitch/activated carbon/$TiO_2$ composite had lots of rutile-type structure which transforms from anatase-type with a little of anatase-type structure. The photocatalytic activities of the composite were evaluated using a photo-decomposition method under UV lamp. The pitch/activated carbon/$TiO_2$ composites were observed better photocatalytic activity than that of pristine $TiO_2$.

• Korean Journal of Pharmacognosy
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• v.16 no.2
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• pp.81-92
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• 1985

The Polygoni Radix and Cynanchi Radix have been used to potentiate the liver functions in clinic of Oriental Medicine. The water extracts of Polygoni Radix and Cynanchi Radix were administered orally to rats intoxicated with carbon tetrachloride and then this experiment have been performed by observing liver fatty degeneration and activities of enzymes such as cytochrome oxidase (CYO), adenosine triphosphatase (ATP), acid phosphatase (ACP), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP). By oral administration of water extracts of the radices between 1 and 10 days, the following results were obtained. 1. The group given Cynanchi Radix extract showed recovery of the fat liver in 4 days, whereas that given Polygoni Radix extract did the recovery in 8 days. 2. In cytochrome oxidase activity, the group given Cynanchi extract showed normal activity in 6 days, whereas that given Polygoni Radix extract did the activity in 8 days. 3. In adenosine triphosphatase activity, the groups given Cynanchi Radix and Polygoni Radix extracts showed normal activities in 2 and 8 days, respectively. 4. In acid phosphatase activity, the groups given Cynanchi Radix and Polygoni Radix extracts showed recovery of the activities in 2 and 4 days, respectively. 5. In lactate dehydrogenase activity, the group given Cynanchi Radix and Polygoni Radix extracts showed recovery of the activities in 6 and 10 days, respectively. 6. In alkaline phosphatase activity, the group given Cynanchi Radix extract showed normal activity in 2 days, whereas that given Polygoni Radix extract showed slight recovery between 4 and 6 days followed by decrease of the activity in 8 and 10 days. From the above-mentioned results, it was found that both of the water extracts of Polygoni and Cynanchi Radix possessed the recovery action of liver function as intoxicated with carbon tetrachloride in rats. It is also noted that the extract of Cynanchi Radix showed more potent activity than that of Polygoni Radix.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.12
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• pp.51-59
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• 1993

A 4${\times}10^{19}cm^{3}$ carbon-doped base AlGaAs/GaAs HBY was grown using carbontetracholoride(CCl$_4$) by atmospheric pressure MOCVD. Abruptness of emitter-base junction was characterized by SIMS(secondary ion mass spectorscopy) and the doping concentration of base layer was confirmed by DXRD(double crystal X-ray diffractometry). Mesa-type HBTs were fabricated using wet etching and lift-off technique. The base sheet resistance of R$_{sheet}$=550${\Omega}$/square was measured using TLM(transmission line model) method. The fabricated transistor achieved a collector-base junction breakdown voltage of BV$_{CBO}$=25V and a critical collector current density of J$_{O}$=40kA/cm$^2$ at V$_{CE}$=2V. The 50$\times$100$\mu$$^2$ emitter transistor showed a common emitter DC current gain of h$_{FE}$=30 at a collector current density of JS1CT=5kA/cm$^2$ and a base current ideality factor of ηS1EBT=1.4. The high frequency characterization of 5$\times$50$\mu$m$^2$ emitter transistor was carried out by on-wafer S-parameter measurement at 0.1~18.1GHz. Current gain cutoff frequency of f$_{T}$=27GHz and maximum oscillation frequency of f$_{max}$=16GHz were obtained from the measured Sparameter and device parameters of small-signal lumped-element equivalent network were extracted using Libra software. The fabricated HBT was proved to be useful to high speed and power spplications.

• Parasites, Hosts and Diseases
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• v.54 no.2
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• pp.123-132
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• 2016

Trichomonas vaginalis causes the most prevalent sexually transmitted infection worldwide. Trichomonads have been detected in prostatic tissues from prostatitis, benign prostatic hyperplasia (BPH), and prostate cancer. Chronic prostatic inflammation is known as a risk factor for prostate enlargement, benign prostatic hyperplasia symptoms, and acute urinary retention. Our aim was to investigate whether T. vaginalis could induce inflammatory responses in cells of a benign prostatic hyperplasia epithelial cell line (BPH-1). When BPH-1 cells were infected with T. vaginalis, the protein and mRNA of inflammatory cytokines, such as CXCL8, CCL2, IL-$1{\beta}$, and IL-6, were increased. The activities of TLR4, ROS, MAPK, JAK2/STAT3, and NF-${\kappa}B$ were also increased, whereas inhibitors of ROS, MAPK, PI3K, NF-${\kappa}B$, and anti-TLR4 antibody decreased the production of the 4 cytokines although the extent of inhibition differed. However, a JAK2 inhibitor inhibited only IL-6 production. Culture supernatants of the BPH-1 cells that had been incubated with live T. vaginalis (trichomonad-conditioned medium, TCM) contained the 4 cytokines and induced the migration of human monocytes (THP-1 cells) and mast cells (HMC-1 cells). TCM conditioned by BPH-1 cells pretreated with NF-${\kappa}B$ inhibitor showed decreased levels of cytokines and induced less migration. Therefore, it is suggested that these cytokines are involved in migration of inflammatory cells. These results suggest that T. vaginalis infection of BPH patients may cause inflammation, which may induce lower urinary tract symptoms (LUTS).

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.29 no.4
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• pp.61-77
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• 2016

목적: 본 연구에서는 TJ 열수추출물이 아토피 피부염에 미치는 효과를 확인하고자 하였다. 방법: 2, 4-dinitrochlorobenzen (DNCB)으로 BALB/c 마우스에 1차 감작 후 3주간 2차 감작을 시행하여 아토피 유사 피부병변을 나타내는 접촉성 피부염을 유발한 뒤 동결건조 처리된 TJ 분말을 (PBS/EtOH/Cremophor=6:1:3)에 용해시켜 쥐의 등 피부에 10, 50 mg/ml 농도로 3주간 도포하였다. 결과: TJ 열수추출물은 아토피 피부 병변의 염증세포 침윤을 억제하였고 (10, 50 mg/ml ) 표피와 진피 두께를 회복시켰으며 (10, 50 mg/ml ), 혈청에서 히스타민 방출을 억제하였다 (00 mg/ml ). 또한 Th2 세포와 관련된 cytokine인 interleukin (IL)-4, IL-5, IL-13과 thymic stromal lymphopoietin (TSLP)의 mRNA 발현 양을 감소시켰고 (10, 50 mg/ml ), Th2 chemokine인 thymus- and activation-regulated chemokine (TARC or CCL17)의 mRNA의 발현 양을 감소시켰다 (10, 50 mg/ml ). 결론: TJ 열수추출물을 BALB/c 마우스에 외용하였을 때 항아토피 효과가 있음을 확인하였으며 따라서 TJ가 아토피 피부염 치료의 외용제로 활용될 수 있을 것으로 사료된다.