• Title/Summary/Keyword: Resistance Model

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Nickel Catalysts Supported on Ash-Free Coal for Steam Reforming of Toluene (무회분탄에 분산된 니켈 촉매의 톨루엔 수증기 개질)

  • PRISCILLA, LIA;KIM, SOOHYUN;YOO, JIHO;CHOI, HOKYUNG;RHIM, YOUNGJOON;LIM, JEONGHWAN;KIM, SANGDO;CHUN, DONGHYUK;LEE, SIHYUN
    • Journal of Hydrogen and New Energy
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    • v.29 no.6
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    • pp.559-569
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    • 2018
  • Catalytic supports made of carbon have many advantages, such as high coking resistance, tailorable pore and surface structures, and ease of recycling of waste catalysts. Moreover, they do not require pre-reduction. In this study, ash-free coal (AFC) was obtained by the thermal extraction of carbonaceous components from raw coal and its performance as a carbon catalytic support was compared with that of well-known activated carbon (AC). Nickel was dispersed on the carbon supports and the resulting catalysts were applied to the steam reforming of toluene (SRT), a model compound of biomass tar. Interestingly, nickel catalysts dispersed on AFC, which has a very small surface area (${\sim}0.13m^2/g$), showed higher activity than those dispersed on AC, which has a large surface area ($1,173A/cm^2$). X-ray diffraction (XRD) analysis showed that the particle size of nickel deposited on AFC was smaller than that deposited on AC, with the average values on AFC ${\approx}11nm$ and on AC ${\approx}23nm$. This proved that heteroatomic functional groups in AFC, such as carboxyls, can provide ion-exchange or adsorption sites for the nano-scale dispersion of nickel. In addition, the pore structure, surface morphology, chemical composition, and chemical state of the prepared catalysts were analyzed using Brunauer-Emmett-Taylor (BET) analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, and temperature-programmed reduction (TPR).

Generation of a transgenic pig expressing human dipeptidylpeptidase-4 (DPP-4) (Human dipeptidylpeptidase-4(DPP-4) 발현 형질전환 돼지의 생산)

  • Chung, Hak Jae;Sa, Soo Jin;Baek, Sun Young;Cho, Eun Suek;Kim, Young Shin;Hong, Jun Ki;Cho, Kyu Ho;Kim, Ji Youn;Park, Mi Ryung;Kim, Kyung Woon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.9
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    • pp.306-314
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    • 2019
  • As dipeptidyl peptidase-4(DPP-4) inhibitors are used widely as a secondary treatment for type 2 diabetes because they tend to be well tolerated with minimal side effects, the human DPP-4(hDPP-4) gene was injected into a pig zygote through micro-injection, and 1-cell stage fertilized embryos were then transplanted surgically into the oviduct. Three pigs were fertilized with hDPP-4 genes and produced sixteen piglets, in which one male piglet was identified to be transgenic. Finally, transgenic pigs showing hDPP-4 gene expression in the tail were produced. Western blot and RT-PCR analysis confirmed that the hDPP-4 is expressed strongly in the membrane cells of the transgenic pig, and that the hDPP-4 gene appears in various tissues and tails. This suggests that the expression vector is normally expressed in transgenic pigs. These results are anticipated to be a model animal to check the endocrine function for insulin resistance that occurs in a hDPP-4 transgenic pig and to increase its value for use as a material in newly developed medicines.

Study on the Suitability of Composite Materials for Enhancement of Automotive Fuel Economy (자동차 연비향상을 위한 복합재료 적용 타당성에 관한 연구)

  • Ju, Yeon Jin;Kwon, Young-Chul;Choi, Heung Soap
    • Composites Research
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    • v.32 no.5
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    • pp.284-289
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    • 2019
  • In the present paper, the dynamic force-moment equilibrium equations, driving power and energy equations are analyzed to formulate the equation for fuel economy(km/liter) equivalent to the driving distance (km) divided by the fuel volume (liter) of the vehicle, a selected model of gasoline powered KIA K3 (1.6v). In addition, the effects of the dynamic parameters such as speed of vehicle (V), vehicle total weight(M), rolling resistance ($C_r$) between tires and road surface, inclined angle of road (${\theta}$), as well as the aerodynamic parameters such as drag coefficient ($C_d$) of vehicle, air density(${\rho}$), cross-sectional area (A) of vehicle, wind speed ($V_w$) have been analyzed. And the possibility of alternative materials such as lightweight metal alloys, fiber reinforced plastic composite materials to replace the conventional steel and casting iron materials and to reduce the weight of the vehicle has been investigated by Ashby's material index method. Through studies, the following results were obtained. The most influencing parameters on the fuel economy at high speed zone (100 km/h) were V, the aerodynamic parameters such as $C_d$, A, ${\rho}$, and $C_r$ and M. While at low speed zone (60 km/h), they are, in magnitude order, dynamic parameters such as V, M, $C_r$ and aerodynamic ones such as $C_d$, A, and ${\rho}$, respectively.

Impact of NR1I2, adenosine triphosphate-binding cassette transporters genetic polymorphisms on the pharmacokinetics of ginsenoside compound K in healthy Chinese volunteers

  • Zhou, Luping;Chen, Lulu;Wang, Yaqin;Huang, Jie;Yang, Guoping;Tan, Zhirong;Wang, Yicheng;Liao, Jianwei;Zhou, Gan;Hu, Kai;Li, Zhenyu;Ouyang, Dongsheng
    • Journal of Ginseng Research
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    • v.43 no.3
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    • pp.460-474
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    • 2019
  • Background: Ginsenoside compound K (CK) is a promising drug candidate for rheumatoid arthritis. This study examined the impact of polymorphisms in NR1I2, adenosine triphosphate-binding cassette (ABC) transporter genes on the pharmacokinetics of CK in healthy Chinese individuals. Methods: Forty-two targeted variants in seven genes were genotyped in 54 participants using Sequenom MassARRAY system to investigate their association with major pharmacokinetic parameters of CK and its metabolite 20(S)-protopanaxadiol (PPD). Subsequently, molecular docking was simulated using the AutoDock Vina program. Results: ABCC4 rs1751034 TT and rs1189437 TT were associated with increased exposure of CK and decreased exposure of 20(S)-PPD, whereas CFTR rs4148688 heterozygous carriers had the lowest maximum concentration ($C_{max}$) of CK. The area under the curve from zero to the time of the last quantifiable concentration ($AUC_{last}$) of CK was decreased in NR1I2 rs1464602 and rs2472682 homozygous carriers, while $C_{max}$ was significantly reduced only in rs2472682. ABCC4 rs1151471 and CFTR rs2283054 influenced the pharmacokinetics of 20(S)-PPD. In addition, several variations in ABCC2, ABCC4, CFTR, and NR1I2 had minor effects on the pharmacokinetics of CK. Quality of the best homology model of multidrug resistance protein 4 (MRP4) was assessed, and the ligand interaction plot showed the mode of interaction of CK with different MRP4 residues. Conlusion: ABCC4 rs1751034 and rs1189437 affected the pharmacokinetics of both CK and 20(S)-PPD. NR1I2 rs1464602 and rs2472682 were only associated with the pharmacokinetics of CK. Thus, these hereditary variances could partly explain the interindividual differences in the pharmacokinetics of CK.

Immunostimulatory Activity of Agarwood through Activation of MAPK Signaling Pathway in RAW 264.7 Murine Macrophages (RAW 264.7 대식세포에서 MAPKs 신호 전달 경로의 활성화를 통한 침향의 면역 자극 활성)

  • Ji, Seon Yeong;Hwangbo, Hyun;Lee, Hyesook;Koo, Young Tae;Kim, Jin Soo;Lee, Ki Won;Noh, Dong Jin;Choi, Yung Hyun
    • Journal of Life Science
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    • v.31 no.8
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    • pp.745-754
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    • 2021
  • Deterioration of the immune function weakens the body's resistance to various infections, leading to a series of diseases. Immunomodulatory biomaterials have been used to reduce the side effects of immunosuppressants or to enhance immunity. Agarwood is the aromatic resinous portion of Aquilaria trees that has been traditionally used as a medicinal herb for the treatment of various diseases. Although previous studies have shown that agarwood can improve the body's immunity, evidence for this claim is still lacking. In this study, the immune-enhancing effects of the agarwood methanol extracts of Aquilaria malaccensis Lamk were evaluated in a RAW 264.7 macrophage model. Based on the results, the agarwood extracts markedly enhanced phagocytosis in the absence of cytotoxicity. The agarwood extract-treated RAW 264.7 cells exhibited the typical morphology of activated macrophages, which are spindle-shaped with elongated filopodia. Agarwood extract also significantly increased the production of nitric oxide (NO), which is associated with the increased expression of inducible NO synthase. Moreover, the secretion and expression levels of cytokines, such as tumor necrosis factor-α and interleukin (IL)-1β and IL-6, were increased by agarwood treatment. Notably, these are also associated with a mitogen-activated protein kinase signaling pathway. Taken together, our findings provide scientific evidence that agarwood has potential immune-enhancing effects in vitro.

The Anti-obesity Effects of Bangpungtongseong-san and Daesiho-tang: A Study Protocol of Randomized, Double-blinded Clinical Trial (방풍통성산 및 대시호탕의 항비만효과 분석: 단일기관 무작위배정 이중맹검 임상시험 프로토콜)

  • Oh, Jihong;Shim, Hyeyoon;Cha, Jiyun;Kim, Ho Seok;Kim, Min Ji;Ahn, Eun Kyung;Lee, Myeong-Jong;Lee, Jun-Hwan;Kim, Hojun
    • Journal of Korean Medicine for Obesity Research
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    • v.20 no.2
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    • pp.138-148
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    • 2020
  • Objectives: The aim of this study is to evaluate the effects of Bangpungtongseong-san (Fangfengtongsheng-san, BTS) and Daesiho-tang (Dachaihu-tang, DST) on weight loss and improvement in lipid metabolism and glucose metabolism. Furthermore, we intend to develop a prediction model for drug effects through the analysis of the single nucleotide polymorphism (SNP), gut-microbiota, and the expression of immune-related biomarkers. Methods: This study is a single-center, randomized, double-blind, parallel-design clinical trial. One hundred twenty-eight participants will be assigned to the BTS group (n=64) and DST group (n=64). Both groups will be administered 4 g medication three times a day for up to 2 weeks. The primary outcomes is weight loss. The secondary outcomes include bioelectrical impedance analysis, waist circumstance, body mass index, total cholesterol, high-density lipoprotein, triglyceride, insulin resistance. The exploratory outcomes include 3-day dietary recall, food frequency questionnaire, quality of life questionnaire, gut microbiota analysis, immune biomarkers analysis, and SNP analysis. Assessment will be made at baseline and at week 4, 8, and 12. Conclusions: This protocol will be implemented by approval of the Institutional Review Board of Dongguk University. The results of this trial will provide a systematic evidence for the treatment of obesity and enable more precise herbal medicine prescriptions.

Effector Memory CD8+ and CD4+ T Cell Immunity Associated with Metabolic Syndrome in Obese Children

  • Yang, Da-Hee;Lee, Hyunju;Lee, Naeun;Shin, Min Sun;Kang, Insoo;Kang, Ki-Soo
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.24 no.4
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    • pp.377-383
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    • 2021
  • Purpose: We investigated the association of effector memory (EM) CD8+ T cell and CD4+ T cell immunity with metabolic syndrome (MS). Methods: Surface and intracellular staining of peripheral blood mononuclear cells was performed. Anti-interleukin-7 receptor-alpha (IL-7Rα) and CX3CR1 antibodies were used to stain the subsets of EM CD8+ T cells, while anti-interferon-gamma (IFN-γ), interleukin-17 (IL-17), and forkhead box P3 (FOXP3) antibodies were used for CD4+ T cell subsets. Results: Of the 47 obese children, 11 were female. Children with MS had significantly higher levels of serum insulin (34.8±13.8 vs. 16.4±6.3 µU/mL, p<0.001) and homeostasis model assessment of insulin resistance (8.9±4.1 vs. 3.9±1.5, p<0.001) than children without MS. Children with MS revealed significantly higher frequencies of IL-7Rαlow CD8+ T cells (60.1±19.1% vs. 48.4±11.5%, p=0.047) and IL-7RαlowCX3CR1+ CD8+ T cells (53.8±20.1% vs. 41.5±11.9%, p=0.036) than children without MS. As the serum triglyceride levels increased, the frequency of IL-7RαlowCX3CR1+ and IL-7RαhighCX3CR1- CD8+ T cells increased and decreased, respectively (r=0.335, p=0.014 and r=-0.350, p=0.010, respectively), in 47 children. However, no CD4+ T cell subset parameters were significantly different between children with and without MS. Conclusion: In obese children with MS, the changes in immunity due to changes in EM CD8+ T cells might be related to the morbidity of obesity.

Development of Permit Vehicle Classification System for Bridge Evaluation in Korea (허가차량 통행에 대한 교량의 안전성 평가를 위한 허가차량 분류 체계 개발)

  • Yu, Sang Seon;Kim, Kyunghyun;Paik, Inyeol;Kim, Ji Hyeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.845-856
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    • 2020
  • This study proposes a bridge evaluation system for indivisible permit vehicles such as hydraulic cranes. The permit loads for the bridge evaluation are divided into three categories: routine permit loads, special permit 1 loads, and special permit 2 loads. Routine permit and special permit 1 vehicles are allowed to cross a bridge with normal traffic. For these two permits, the standard lane model in the Korean Highway Bridge Design Code was adopted to consider normal traffic in the same lane. Special permit 2 vehicles are assumed to cross a bridge without other traffic. Structural analyses of two prestressed-beam bridges and two steel box girder bridges were conducted for the proposed permit loads. The rating factors of the four bridges for all permit loads were calculated as sufficiently large values for the moment and shear force so that crossing the bridges can be permitted. A reliability assessment of the bridges was performed to identify the reliability levels for the permit vehicles. It was confirmed that the reliability level of the minimum required strength obtained by the load-resistance factors yields the target reliability index of the design code for the permit vehicles.

Caulerpa okamurae ethanol extract improves the glucose metabolism and insulin sensitivity in vitro and in vivo (옥덩굴 에탄올 추출물의 당 대사 및 인슐린 민감성 개선효과)

  • Park, Chul-Min;Thakuri, Laxmi Sen;Rhyu, Dong-Young
    • Journal of Applied Biological Chemistry
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    • v.64 no.1
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    • pp.89-96
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    • 2021
  • The aim of this study is to examine the effect of Caulerpa okamurae ethanol extract (COE) on glucose metabolism and insulin sensitivity as one of the drug targets for treatment of type2 diabetes. COE significantly inhibited protein tyrosine phosphatase (PTP1B) and dipeptidyl peptidase-IV (DPP-IV) enzyme activities in vitro assay. Also, COE significantly enhanced the glucose uptake and the expression of insulin receptor substrate-1 (IRS-1) and glucose transporter4 (GLUT4) proteins in 3T3-L1 adipocytes or zebrafish larvae compared with control. In dexamethasone-induced resistance model of L6 myotubes, the protein expression of insulin signaling and glucose uptake was effectively increased by the treatment of COE. In contrast, the elevated phosphorylation of IRS-1 Ser307 was normally suppressed by treatment of COE. However, COE had no effect on insulin secretion in pancreatic beta cells. Thus, our results suggest that COE improves the glucose metabolism and insulin sensitivity through the regulation of insulin signaling and GLUT4 protein in insulin's target cells and zebrafish larvae.

Estimation of Maneuverability of Underwater Vehicles with Ahead Propeller by the Vertical Planar Motion Mechanism Test (VPMM 시험을 통한 선수부에 프로펠러를 갖는 수중운동체의 조종성능 추정)

  • Shin, Myung-Sub;Kim, Dong-Hwi;Kim, Yagin;Hwang, Jong-Hyon;Baek, Hyung-Min;Kim, Sung-Jae;Park, Sang-Jun;Choi, Young-Myung;Park, Hongrae;Kim, Eun-Soo
    • Journal of Navigation and Port Research
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    • v.46 no.3
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    • pp.168-178
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    • 2022
  • In this study, the resistance test, the vertical static angle of the attack test and VPMM test will be conducted to estimate the maneuverability of underwater vehicles with ahead propeller. The vertical static test will be conducted within the range of -40deg to 40deg, to investigate the cross-flow drag at high incidence angles. The tests will be conducted by dividing the propeller rotation into a case in which the propeller rotates at a specific rpm, and a case in which the propeller rotates naturally, according to the towing speed. Hydrodynamic coefficients of vertical direction will be estimated by the captive model tests. Additionally, the vertical dynamic stability index based on estimated hydrodynamic coefficients will be calculated and the impact of the propeller revolution state on the index will be investigated. The results are expected to be used as reference test data for underwater vehicles with ahead propeller.