• 한국분말재료학회지
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• 제26권1호
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• pp.49-57
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• 2019

Layered $LiNi_{0.83}Co_{0.11}Mn_{0.06}O_2$ cathode materials single- and dual-doped by the rare-earth elements Ce and Nd are successfully fabricated by using a coprecipitation-assisted solid-phase method. For comparison purposes, non-doping pristine $LiNi_{0.83}Co_{0.11}Mn_{0.06}O_2$ cathode material is also prepared using the same method. The crystal structure, morphology, and electrochemical performances are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) mapping, and electrochemical techniques. The XRD data demonstrates that all prepared samples maintain a typical ${\alpha}-NaFeO_2$-layered structure with the R-3m space group, and that the doped samples with Ce and/or Nd have lower cation mixing than that of pristine samples without doping. The results of SEM and EDS show that doped elements are uniformly distributed in all samples. The electrochemical performances of all doped samples are better than those of pristine samples without doping. In addition, the Ce/Nd dual-doped cathode material shows the best cycling performance and the least capacity loss. At a 10 C-rate, the electrodes of Ce/Nd dual-doped cathode material exhibit good capacity retention of 72.7, 58.5, and 45.2% after 100, 200, and 300 cycles, respectively, compared to those of pristine samples without doping (24.4, 11.1, and 8.0%).

• Journal of Applied Biological Chemistry
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• 제59권1호
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• pp.49-56
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• 2016

The current study investigated the anti-obesity effect of Cissus quadrangularsis extracts (CQR-300) and its molecular action mechanism on obese mice induced high-fat diet (HFD). To induce the obesity, mice were fed a HFD for 6 weeks and then fed HFD only or HFD with CQR-300 at 50 and 200 mg/kg. Then, body weight gain and white adipose tissue weights were measured. We investigated the reduction in body fat and the regulation of fatty acid synthesis was measured by dual energy X-ray absorptiometry and real-time PCR with Western blot, respectively. In vitro study, CQR-300 inhibited pancreatic lipase activity. The CQR-300 treatment was significantly decreased the body weight gain and adipocytes size as well as white adipose tissues weights in HFD-induced obese mice. Furthermore, CQR-300 reduced the body fat and fat mass with regulating of adipose tissue hormones as leptin. Treatment with 50 mg/kg CQR-300 showed effectively lower expression levels of adipogenesis/lipogenesis related genes and proteins such as CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$), Sterol regulatory element binding protein-1c (SREBP-1c), and fatty acid synthase (FAS) in white adipose tissue (WAT) as compared with the HFD fed only mice. These results suggest that the CQR-300 has an anti-obesity effect via inhibition of lipase activity, decrease the body fat mass by regulating the adipogenesis and lipogenesis related genes and proteins in epididymal adipose tissue with evaluate body fat reduce in the HFD-induced obese mice.

• 약학회지
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• 제37권2호
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• pp.136-142
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• 1993

To a suspension of 1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-{3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl}-4-oxo-3-quinoline carboxylic acid(C1) in sodium hydroxide solution and water is added dropwise with stirring carbon disulfide. [6R-[6$\alpha$, 7$\beta$(Z)]]-7-[[[2-Amino-4-thiazoly)methoxyimino]-acetyl]amino]-3-[[[[7-( 3-carboxy-1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxo-7-guinolonyl)-3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl]thioxomethyl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-2-carboxylic acid (DACD) was synthesized from 1-cyclopropyl-6,8-difluoro-1,4-dihydro-7-[7-(mercapto) thioxomethyl-[3,7-dia zabicyclo[3.3.0]oct-1(5)-en-3-yl}]-4-oxo-3-quinoline carboxylic acid disodium salt(C2) and cefotaxime. The invitro activity of novel dual-action cephalosporin, DACD, was compared with the in vitro activities of CENO(cefotaxime 3'-norfloxacin dithiocarbamate), cefotaxime, and norfloxacin against a variety of bacterial species. In vitro activity of DACD was superior to that of norfloxacin against Streptococcus pyogenes. Against Gram-positive and Gram-negative bacteria, its activity was almost equal to that of CENO.

• The Korean Journal of Physiology and Pharmacology
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• 제23권5호
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• pp.403-409
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• 2019

Free fatty acid (FFA) intake regulates blood pressure and vascular reactivity but its direct effect on contractility of systemic arteries is not well understood. We investigated the effects of saturated fatty acid (SFA, palmitic acid), polyunsaturated fatty acid (PUFA, linoleic acid), and monounsaturated fatty acid (MUFA, oleic acid) on the contractility of isolated mesenteric (MA) and deep femoral arteries (DFA) of Sprague-Dawley rats. Isolated MA and DFA were mounted on a dual wire myograph and phenylephrine (PhE, $1-10{\mu}M$) concentration-dependent contraction was obtained with or without FFAs. Incubation with $100{\mu}M$ of palmitic acid significantly increased PhE-induced contraction in both arteries. In MA, treatment with $100{\mu}M$ of linoleic acid decreased $1{\mu}M$ PhE-induced contraction while increasing the response to higher PhE concentrations. In DFA, linoleic acid slightly decreased PhE-induced contraction while $200{\mu}M$ oleic acid significantly decreased it. In MA, oleic acid reduced contraction at low PhE concentration (1 and $2{\mu}M$) while increasing it at $10{\mu}M$ PhE. Perplexingly, depolarization by 40 mM KCl-induced contraction of MA was commonly enhanced by the three fatty acids. The 40 mM KCl-contraction of DFA was also augmented by linoleic and oleic acids while not affected by palmitic acid. SFA persistently increased alpha-adrenergic contraction of systemic arteries whereas PUFA and MUFA attenuated PhE-induced contraction of skeletal arteries. PUFA and MUFA concentration-dependent dual effects on MA suggest differential mechanisms depending on the types of arteries. Further studies are needed to elucidate underlying mechanisms of the various effects of FFA on systemic arteries.

• 대한한의학회지
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• 제27권4호
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• pp.182-190
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• 2006

Objective : Based on immunological mechanisms, this study examined whether subcutaneous (s.c.) injection of Clematis mandshurica Maxim. water extract (CMA) has anti-inflammatory effects, and its effect on $TNF-{\alpha}$, IL-1 and IL-10 release from synoviocytes on adjuvant arthritis (AA) in the rat. Methods : Complete Freund's adjuvant was used to induce AA in rats. Synoviocytes were separated by the method of collagenase and DNase digestion Synoviocytes proliferation was assayed by 3-(4, 5 dimethylthiazol 2 yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. $TNF-{\alpha}$, IL-1 and interleukin-10 (IL-10) production of synoviocytes was measured with ELISA. The expression of IL-10 mRNA of synoviocytes was determined using RT PCR. Results : There were significant secondary inflammatory reactions in AA rats, accompanied by the decrease of body and immune organs weight simultaneously. Synoviocytes proliferation of AA rats significantly increased, and the levels of $TNF-{\alpha}$ and IL-1 in supernatants of synoviocytes in AA rats were also elevated compared with the sham group. The administration of CMA (2, 5, 10 mg/kg, s.c.) reduced the above changes significantly. In contrast to $TNF-{\alpha}$ and IL-1, IL-10 production and the level of its mRNA of synoviocytes in AA rats apparently decreased. CMA (2, 5, 10 mg/kg, s.c.) markedly increased IL-10 in synoviocytes at protein and transcription level. Conclusion : The results indicate that CMA has a beneficial effect on rat AA due to modulating inflammatory cytokine production of synoviocytes, which play a crucial role in the pathogenesis of this disease.

• Molecules and Cells
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• 제41권8호
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• pp.762-770
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• 2018

Adiponectin, a hormone produced by adipose tissue, is very abundant in plasma, and its anti- and pro-inflammatory effects are reported. However, the mechanisms of these pro- and anti-inflammatory effects are not fully defined. Herein, we evaluated the dual inflammatory response mechanism of adiponectin in macrophages. Short-term globular adiponectin (gAd) treatment induced $I{\kappa}B{\alpha}$ degradation, $NF-{\kappa}B$ nuclear translocation, and $TNF-{\alpha}$ production in RAW 264.7 cells. Polymyxin B pretreatment did not block gAd-induced $I{\kappa}B{\alpha}$ degradation, and heated gAd was unable to degrade $I{\kappa}B{\alpha}$, suggesting that the effects of gAd were not due to endotoxin contamination. gAd activated IKK and Akt, and inhibition of either IKK or Akt by dominant-negative $IKK{\beta}$ ($DN-IKK{\beta}$) or DN-Akt overexpression blocked gAd-induced $I{\kappa}B{\alpha}$ degradation, suggesting that short-term incubation with gAd mediates inflammatory responses by activating the $I{\kappa}B/NF-{\kappa}B$ and PI3K/Akt pathways. Contrastingly, long-term stimulation with gAd induced, upon subsequent stimulation, tolerance to gAd, lipopolysaccharide, and CpG-oligodeoxynucleotide, which is associated with gAd-induced downregulation of IL-receptor-associated kinase-1 (IRAK-1) due to IRAK-1 transcriptional repression. Conclusively, our findings demonstrate that the pro- and anti-inflammatory responses to gAd in innate immune cells are time-dependent, and mediated by the activation of the $I{\kappa}B/NF-{\kappa}B$ pathway, and IRAK-1 downregulation, respectively.

• Structural Engineering and Mechanics
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• 제51권4호
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• pp.627-641
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• 2014

Functionally graded steels (FGSs) are a family of functionally graded materials (FGMs) consisting of ferrite (${\alpha}$), austenite (${\gamma}$), bainite (${\beta}$) and martensite (M) phases placed on each other in different configurations and produced via electroslag remelting (ESR). In this research, the flow stress of dual layer austenitic-martensitic functionally graded steels under hot deformation loading has been modeled considering the constitutive equations which describe the continuous effect of temperature and strain rate on the flow stress. The mechanism-based strain gradient plasticity theory is used here to determine the position of each layer considering the relationship between the hardness of the layer and the composite dislocation density profile. Then, the released energy of each layer under a specified loading condition (temperature and strain rate) is related to the dislocation density utilizing the mechanism-based strain gradient plasticity theory. The flow stress of the considered FGS is obtained by using the appropriate coefficients in the constitutive equations of each layer. Finally, the theoretical model is compared with the experimental results measured in the temperature range $1000-1200^{\circ}C$ and strain rate 0.01-1 s-1 and a sound agreement is found.

• 대한전자공학회논문지TC
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• 제37권2호
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• pp.83-90
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• 2000

본 논문에서는 이중공진 및 광대역, 고이득의 특성을 갖는 적층된 원형-디스크 마이크로스트립 1×4 배열 안테나를 차세대 이동통신인 IMT-2000시스템(상향링크: 1.885 GHz∼2.025 GHz, 하향링크: 2.11 GHz∼2.2 GHz)기지국에서 응용할 수 있도록 설계 제작 및 실험하였다. 실험결과 상향:l.885 GHz, 하향:2.178 GHz로 원하는 주파수대에서 정확히 이중 공진하고, 궤환 손실은 -30.19dB, -24.99dB로 나타났으며 VSWR은 각각 1.06, 1.43, 그리고 VSWR<2 에서의 대역폭 402 MHz, -3dB 빔 폭은 1.88 GHz에서( αE :16.8。, αH : 69。), 2.178 GHz에서(αE:15.2。, αH:51.5。)를 갖고, 이득은 사용 하고자 하는 주파수 전반에 거쳐 약 13.7 dBi∼15.21 dBi의 이득을 얻었다.

• 대한화학회지
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• 제29권3호
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• pp.277-282
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• 1985

N-benzylideneaniline 유도체의 C-phenyl group 파라위치에 치환기가 변화함에 따라 imidoyl양성자의 화학적 이동 (H${\alpha}$-SCS)에 미치는 자유에너지 직선관계(LFER)를 검토하기 위하여 치환기별 H$_{\alpha}$-SCS와 ${\sigma}$,${\sigma}^+$, ${\sigma}_I$,${\sigma}_R$, F 및 R등의 여러가지 자유에너지 관계 파라미터를 Hammett, Okamoto-Brown식과 그리고 Taft, Swain-Lupton의 DSP식에 적용한 바, 2.8∼3.2의 섞임계수(blending coefficient values, ${\lambda}$)값을 얻음으로써 공명효과(R)가 유발효과(I)나 장효과(F)보다 H_${\sigma}$-SCS에 크게 영향을 미친다는 사실을 알 수 있었으며 Swain-Lupton의 식으로 구한 %R = 66.6 and %F = 33.4의 값으로 부터 H$_{\sigma}$-SCS에 미치는 공명효과(R)와 장효과(F)의 비가 2:1이라는 정량적인 관계를 알았다.

• 한국자동차공학회논문집
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• 제15권6호
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• pp.87-93
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• 2007

It is complicate to analysis the systems, dual mode hybrid systems, because they are composed of many planetary gear sets. For the performance test, it needs to define the systems with representative parameters. In this paper, system parameters, $\alpha$, $\beta$, $\zeta$, are introduced to define the systems, and an arbitrary system like E-IVT developed by Renault Motors is converted to the general system having equivalent parameters, such as $\beta'$, $R'_b$. Pontryagin principle and Kuhn-Tucker condition method are applied to solve the constrained problems, by which the methodology for accelerating test is generalized, and the results of the simulation are reported. In addition, the effects of alternative strategies are mentioned. The method of fuel economy test at engine mode is also introduced. The results of test at engine mode is different from the results of optimal trajectory, but the fuel economy of the engine mode is related to the highway driving and optimized operating of the system.