• 제목/요약/키워드: induced polarization

검색결과 300건 처리시간 0.022초

SOCS3 Attenuates Dexamethasone-Induced M2 Polarization by Down-Regulation of GILZ via ROS- and p38 MAPK-Dependent Pathways

  • Hana Jeong;Hyeyoung Yoon;Yerin Lee;Jun Tae Kim;Moses Yang;Gayoung Kim;Bom Jung;Seok Hee Park;Choong-Eun Lee
    • IMMUNE NETWORK
    • /
    • 제22권4호
    • /
    • pp.33.1-33.17
    • /
    • 2022
  • Suppressors of cytokine signaling (SOCS) have emerged as potential regulators of macrophage function. We have investigated mechanisms of SOCS3 action on type 2 macrophage (M2) differentiation induced by glucocorticoid using human monocytic cell lines and mouse bone marrow-derived macrophages. Treatment of THP1 monocytic cells with dexamethasone (Dex) induced ROS generation and M2 polarization promoting IL-10 and TGF-β production, while suppressing IL-1β, TNF-α and IL-6 production. SOCS3 over-expression reduced, whereas SOCS3 ablation enhanced IL-10 and TGF-β induction with concomitant regulation of ROS. As a mediator of M2 differentiation, glucocorticoid-induced leucine zipper (GILZ) was down-regulated by SOCS3 and up-regulated by shSOCS3. The induction of GILZ and IL-10 by Dex was dependent on ROS and p38 MAPK activity. Importantly, GILZ ablation led to the inhibition of ROS generation and anti-inflammatory cytokine induction by Dex. Moreover, GILZ knock-down negated the up-regulation of IL-10 production induced by shSOCS3 transduction. Our data suggest that SOCS3 targets ROS- and p38-dependent GILZ expression to suppress Dex-induced M2 polarization.

Effects of Wavelength Dependent Birefringence inside a Fiber Cavity on the Fiber Laser Output Characteristics with a Nonlinear Amplifying Loop Mirror

  • Kim, Ho-Young;Kim, Kyong-Hon;Lee, El-Hang
    • Journal of the Optical Society of Korea
    • /
    • 제2권2호
    • /
    • pp.64-73
    • /
    • 1998
  • We have theoretically analyzed and experimentally observed the effects of wavelength dependent birefringence inside a laser cavity on the output characteristics of fiber lasers with a figure eight geometry. The spectral and polarization characteristics of fiber lasers are found to be very susceptible to the resultant birefringence composed of the intrinsically existing wavelength dependent birefringence and the externally induced birefringences inside the fiber. For the variation of twist-induced birefringence inside the nonlinear amplifying loop mirror, the laser output power and center wave-length of continuous wave lasers change periodically, but the polarization characteristics remains nearly unchanged. The changes of the birefringence inside the linear loop has little effect on the spectral characteristics but changes the polarization properties such as the polarization direction.

금풍광산 광화대에 대한 전기탐사 반응 (Electrical Responses on Mineralized Zone in Geumpung Mine)

  • 정연호;김정호;변중무
    • 한국지구물리탐사학회:학술대회논문집
    • /
    • 한국지구물리탐사학회 2007년도 공동학술대회 논문집
    • /
    • pp.231-236
    • /
    • 2007
  • Electrical resistivity, self-potential and time-domain induced polarization methods were conducted for study of electrical responses on vein-type sulfides ore, which is intruding limestone and dolomite of Ordovician, of Geumpung mine located in Dojeon-ri, Susan-myeon, Jecheon-si, Chungbuk. Sulfides bearing chalcopyrite, pyrrhotite and galena etc. are deposited in disseminated or vein-type. Good result that resistivity and self-potential surveys detect high grade-estimated mineralized zone located in upper part of existing low grade ore zone is acquisited and is to some extent consistent with induced polarization. Furthmore, a new mineralization zone directing EW is detected.

  • PDF

Gamma-aminobutyric acid-salt attenuated high cholesterol/high salt diet induced hypertension in mice

  • Son, Myeongjoo;Oh, Seyeon;Lee, Hye Sun;Choi, Junwon;Lee, Bae-Jin;Park, Joung-Hyun;Park, Chul Hyun;Son, Kuk Hui;Byun, Kyunghee
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제25권1호
    • /
    • pp.27-38
    • /
    • 2021
  • Excessive salt intake induces hypertension, but several gamma-aminobutyric acid (GABA) supplements have been shown to reduce blood pressure. GABA-salt, a fermented salt by L. brevis BJ20 containing GABA was prepared through the post-fermentation with refined salt and the fermented GABA extract. We evaluated the effect of GABA-salt on hypertension in a high salt, high cholesterol diet induced mouse model. We analyzed type 1 macrophage (M1) polarization, the expression of M1 related cytokines, GABA receptor expression, endothelial cell (EC) dysfunction, vascular smooth muscle cell (VSMC) proliferation, and medial thicknesses in mice model. GABA-salt attenuated diet-induced blood pressure increases, M1 polarization, and TNF-α and inducible nitric oxide synthase (NOS) levels in mouse aortas, and in salt treated macrophages in vitro. Furthermore, GABA-salt induced higher GABAB receptor and endothelial NOS (eNOS) and eNOS phosphorylation levels than those observed in salt treated ECs. In addition, GABA-salt attenuated EC dysfunction by decreasing the levels of adhesion molecules (E-selectin, Intercellular Adhesion Molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1]) and of von Willebrand Factor and reduced EC death. GABA-salt also reduced diet-induced reductions in the levels of eNOS, phosphorylated eNOS, VSMC proliferation and medial thickening in mouse aortic tissues, and attenuated Endothelin-1 levels in salt treated VSMCs. In summary, GABA-salt reduced high salt, high cholesterol diet induced hypertension in our mouse model by reducing M1 polarization, EC dysfunction, and VSMC proliferation.

폴링된 폴리머 광도파로의 광축을 조절하여 제작한 수동형 편광 변환기 (Passive Polarization Converter Fabricated by Controlling Optic Axis of Poled Polymer Waveguides)

  • 오민철;신상영
    • 전자공학회논문지A
    • /
    • 제32A권12호
    • /
    • pp.166-172
    • /
    • 1995
  • A novel passive TE/TM polarization mode converter is fabricated by using poled polymer waveguides. The optic axis of the poling induced waveguide is slowly rotated by using a slowly varying structure of poling electrodes. Thus the polarization conversion is achieved as the guided mode propagates through the waveguide. The proposed device is simulated by a full vectorial beam propagation method (VBPM) for anisotropic medium. For the rotation length of 1 mm, the TE polarization of the guided mode is successfully converted to the TM polarization with negligible loss. Based on the simulation results, we fabricated the polarization converter which is tested by using 1.3 $\mu$m laser diode. TE to TM mode conversion is observed with a polarization extinction ratio higher than 30 dB, and the excess loss is less than 1 dB. The polarization conversion is relatively insensitive to wavelength since the device contains no periodic structures. These devices are easier to fabricate than others containing periodic structures.

  • PDF

$\textrm{0.9Pb}\textrm({Mg}_{1/3}\textrm{Nb}_{2/3})\textrm{O}_3$-$\textrm{0.1PbTiO}_3$계 강유전체에서 전계인가에 따른 분극 및 변위의 상관관계 (Correlations between the Polarization and Strain Induced by Electric field in $\textrm{0.9Pb}\textrm({Mg}_{1/3}\textrm{Nb}_{2/3})\textrm{O}_3$-$\textrm{0.1PbTiO}_3$ Relaxor Ferroelectrics)

  • 박재환;박재관;박순자
    • 한국재료학회지
    • /
    • 제9권1호
    • /
    • pp.81-85
    • /
    • 1999
  • Polarization and strain induced by unipolar electric field (P\ulcorner, S\ulcorner), those induced by bipolar electric field (P, S) and remanent polarization (P\ulcorner) were investigated in 0.9Pb(Mg\ulcornerNb\ulcorner)O$_3$-$0.1PbTiO_3$relaxor ferroelectric ceramics in the temperature range of $-50^{\circ}C$~$90^{\circ}C$. From the temperature dependence of polarization and strain, the transition from predominantly paraelectric (electrostrictive) to partially ferroelectric (piezoelectric) is visualized. Under the given temperature, the P\ulcorner/P\ulcorner is always larger than the S\ulcorner/S\ulcorner and the difference between them becomes larger ass the temperature decrease. The S\ulcorner/P\ulcorner increases as the temperature decreased below phase transition temperature. It was suggested that these experimental results might be explained with a simple rigid ion model concentrating on BO\ulcorner octahedron.

  • PDF

전기비저항과 유도분극을 활용한 TBM 터널 굴착면 전방 토사지반 및 핵석지반 예측 기법 (Forward probing utilizing electrical resistivity and induced polarization for predicting soil and core-stoned ground ahead of TBM tunnel face)

  • 강대훈;이인모;정지희;김도형
    • 한국터널지하공간학회 논문집
    • /
    • 제21권3호
    • /
    • pp.323-345
    • /
    • 2019
  • 토사지반과 핵석지반에서 EPB 쉴드 TBM을 통한 성공적인 터널 시공을 위해서 굴착면 전방의 지반 정보를 정확히 파악하는 것이 필요하다. 본 연구에서는 전기비저항 탐사와 유도분극(induced polarization) 탐사를 함께 활용하여 복합토사지반과 핵석지반에 대한 전방 예측 방안을 제시하고자 하였다. 토사지반의 구성은 EPB 쉴드 TBM에서 첨가재 선택에 필수요소이며, 핵석지반은 기계화 시공에서 난이도가 높은 지반이기 때문이다. 탐사는 TBM이 굴진을 멈추고 세그먼트 1링을 조립할 시에 커터헤드에 설치된 4개의 전극을 활용하여 수행된다고 보았다. 토사지반의 경우 화강풍화토, 모래, 점토로 구성된 복합지반에 대해 축소모사하여 실내실험을 수행하였다. 실험 결과 전기비저항은 복합지반 이론해와 상당히 일치하였으며 유도분극은 경우에 따라 전기비저항과 경향성이 일치하거나 완전히 상반되었다. 이러한 결과를 토대로 실제 현장에서 적용 가능한 토사지반 예측방안을 제시하였다. 핵석지반의 경우 균질지반에서 핵석지반으로 굴착해 나가는 상황을 축소모사하였으며 핵석의 불규칙성을 난수를 통해 모사하였다. 실험결과 전기비저항은 핵석지반에 접근할수록 증가하였고 유도분극은 불규칙하게 오르내림을 거듭하는 경향을 나타내었다.

적층형 세라믹 액츄에이터의 세라믹-전극간 계면이 전기적 특성에 미치는 영향에 대한 연구 (Effect of Ceramic-Electrode Interface on the Electrical Properties of Multilayer Ceramic Actuators)

  • 하문수;정순종;송재성;이재신
    • 한국전기전자재료학회논문지
    • /
    • 제15권10호
    • /
    • pp.896-901
    • /
    • 2002
  • The polarization and strain behavior of multilayer ceramic actuators fabricated by tape casting using a PNN-PZT ceramics were investigated in association with electrode size and internal layer number. Spontaneous polarization and strain decreased with increasing electrode size. In addition, the increase of internal layer number brought reduced spontaneous polarization and increased the field-induced strain. Because the actuators structure is designed to stack ceramic layer and electrode layer alternatively, the ceramic-electrode interfaces may act as a resistance to motion of domain wall. To analyze the effect of ceramic-electrode interface, the diffraction intensity ratio of (002) to (200) planes was calculated from X-ray diffraction patterns of samples subjected to a voltage of 200 V. The diffraction intensity ratio of (002) to (200) planes was decreased with increasing electrode size and internal layer number. The diffraction intensity ratio and straining behavior analyses indicate that the Polarization and strain were affected by the amount of 90°domain decreasing with increasing electrode size and internal layer number. Consequently, the change of polarization and displacement with respect to electrode size and layer number is likely to be caused by readiness of the domain wall movement around the interface.

Sensitivity Enhancement in Solution NMR via Photochemically Induced Dynamic Nuclear Polarization

  • Im, Jonghyuk;Lee, Jung Ho
    • 한국자기공명학회논문지
    • /
    • 제21권1호
    • /
    • pp.1-6
    • /
    • 2017
  • Enhancements in NMR sensitivity have been the main driving force to extend the boundaries of NMR applications. Recently, techniques to shift the thermally populated nuclear spin states are employed to gain high NMR signals. Here, we introduce a technique called photochemically induced dynamic nuclear polarization (photo-CIDNP) and discuss its progresses in enhancing the solution-state NMR sensitivity.

A Simple Method for the Monitoring of Photo-induced Alignment of the Azobenzene Molecules in a Poly(malonic ester)

  • Shin, H.D.;Hwang, U.J.;Oh, C.H.;Song, S.H.;Kim, P.S.;Han, Y.K.
    • Journal of Korean Vacuum Science & Technology
    • /
    • 제6권1호
    • /
    • pp.1-4
    • /
    • 2002
  • A simple method for real-time monitoring the molecular orientation in a polymeric film was suggested. This method was examined in the polarization holograms by two recording beams on a poly(malonic ester) containing disperse red 1. The spatial distributions of the photo-induced alignment were measured and analyzed at various polarization states of two recording beams. As the result, the directions of molecular alignments could be identified easily by our method.

  • PDF