• 제목/요약/키워드: NA sensors

검색결과 221건 처리시간 0.027초

CD72 is a Negative Regulator of B Cell Responses to Nuclear Lupus Self-antigens and Development of Systemic Lupus Erythematosus

  • Takeshi Tsubata
    • IMMUNE NETWORK
    • /
    • 제19권1호
    • /
    • pp.1.1-1.13
    • /
    • 2019
  • Systemic lupus erythematosus (SLE) is the prototypic systemic autoimmune disease characterized by production of autoantibodies to various nuclear antigens and overexpression of genes regulated by IFN-I called IFN signature. Genetic studies on SLE patients and mutational analyses of mouse models demonstrate crucial roles of nucleic acid (NA) sensors in development of SLE. Although NA sensors are involved in induction of antimicrobial immune responses by recognizing microbial NAs, recognition of self NAs by NA sensors induces production of autoantibodies to NAs in B cells and production of IFN-I in plasmacytoid dendritic cells. Among various NA sensors, the endosomal RNA sensor TLR7 plays an essential role in development of SLE at least in mouse models. CD72 is an inhibitory B cell co-receptor containing an immunoreceptor tyrosine-based inhibition motif (ITIM) in the cytoplasmic region and a C-type lectin like-domain (CTLD) in the extracellular region. CD72 is known to regulate development of SLE because CD72 polymorphisms associate with SLE in both human and mice and CD72-/- mice develop relatively severe lupus-like disease. CD72 specifically recognizes the RNA-containing endogenous TLR7 ligand Sm/RNP by its extracellular CTLD, and inhibits B cell responses to Sm/RNP by ITIM-mediated signal inhibition. These findings indicate that CD72 inhibits development of SLE by suppressing TLR7-dependent B cell response to self NAs. CD72 is thus involved in discrimination of self-NAs from microbial NAs by specifically suppressing autoimmune responses to self-NAs.

Spectroscopic characterization of electroluminescent ZnS:Cu,Cl phosphor coated by sol-gel process

  • Lee, You-Hui;Han, Chi-Hwan;Han, Sang-Do;Chang, Mi-Youn;Sharma, Gaytri.;Park, Youn-Bong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
    • /
    • pp.1323-1326
    • /
    • 2005
  • The photoluminescence, electroluminescence and surface properties of ZnS:Cu,Cl phosphor coated by sol-gel process were studies. Na-silicate was used as precursor coating material. pH of solution and the concentration of Na-silicate are the important conditions to obtain the uniform coating on the phosphors. Also, the electroluminescent devices were made with Na-silicate coated phosphor. The spectroscopic characterization is performed by photospectrometer.

  • PDF

CaO를 첨가한 Na고체전해질 센서의 CO2가스 감도향상에 관한 연구 (A study on improving sensitivity to CO2 gases of Na solid electrolyte sensors adding CaO)

  • 곽종식;서무교;최순돈;이덕동
    • 센서학회지
    • /
    • 제11권4호
    • /
    • pp.218-223
    • /
    • 2002
  • $CO_2$ 가스 감도를 높임과 동시에 감지거동을 안정화시키기 위하여 여러 함량의 CaO가 함유된 NASICON 전해질을 낮은 온도에서 소결하여 NASICON 센서를 제작하였다. 제조된 소자는 비교적 낮은 동작온도인 $250^{\circ}C$정도에서도 양호한 감도와 안정된 출력특성을 나타내었다.

Na2CO3-CaCO3 보조상을 사용한 후막형 Co2 센서의 특성연구 (Characteristics of thick film Co2 sensors attached with Na2CO3-CaCO3 auxiliary phases)

  • 심한별;최정운;강주현;유광수
    • 센서학회지
    • /
    • 제15권3호
    • /
    • pp.168-172
    • /
    • 2006
  • Potentiometric $CO_{2}$ sensors were fabricated using a NASICON ($Na_{1+x}Zr_{2}Si_{X}P_{3-X}O_{12}$, 1.8 < x < 2.4) thick film and auxiliary layers. The powder of a precursor of NASICON with high purity was synthesized by a sol-gel method. By using the NASICON paste, an electrolyte was prepared on the alumina substrate by screen printing and then sintered at $1000^{\circ}C$ for 4 h. A series of $Na_{2}CO_{3}-CaCO_{3}$ auxiliary phases were deposited on the Pt sensing electrode. The electromotive force (emf) values were linearly dependent on the logarithm of $CO_{2}$ concentration in the range between 1,000 and 10,000 ppm. The device attached with $Na_{2}CO_{3}-CaCO_{3}$ (1:2 in mol.%) showed good sensing properties in the low temperatures.

종이접기 기반 자극 반응성 하이드젤 온도 센서 연구 (Origami inspired Temperature Sensor based on Stimuli-Responsive Hydrogel)

  • 나준희
    • 센서학회지
    • /
    • 제26권1호
    • /
    • pp.35-38
    • /
    • 2017
  • A thermally responsive hydrogel has reversibility with temperature during swelling. Here, we proposed origami inspired temperature sensor by using multi-layered hydrogel film. The formation of patterned stripes on microscale film drives bending to an angle that can be controlled linearly. Although temperature range was not wide, measured sensitivity of sensors has high resolution and accuracy. It providing a powerful platform for the design of sensitive sensors and that easily adapt other type of sensors in microscale.

연속 기체흐름계 및 일시 기체흐름계에서의 고체 전해질 $CO_2$ 가스센서의 열역학적 분석 (Thermodynamic Analysis of Solid Electrolyte $CO_2$ Sensor in Continuous and Discontinuous Flow Systems)

  • 최순돈
    • 센서학회지
    • /
    • 제7권5호
    • /
    • pp.319-326
    • /
    • 1998
  • 연속 기체흐름계에서 감지막으로 $Na_2CO_3$$MCO_3$ ($M=Cs_2,K_2,Li_2,Ca$)를 입힌 $Na^+$ 이온 전해질 센서가 $CO_2$ 가스를 감지할 때 anode반응을 도출하였다. 흔히 사용되는 전기화학 센서에 대해 일반적으로 알려진 전체 전극반응인 $MCO_3=MO+CO_2$ 반응은 위의 $Na^+$이온 전해질 센서에는 적합한 반응이 아니었다. 따라서 anode 반응은 전체cell 내의 ionic balance를 유지하기 위해 전해질과 감지막 계면에 이온교환반응을 첨가시킴으로써 도출할 수 있었으며 anode반응은 $Na_2CO_3$ 및 감지막의 금속($M^{++}$) 이온이 포함된 산화물이 참가하는 반응임을 알 수 있었다. 이와 같이 도출된 전극반응으로부터 구한 EMF와 일시 기체흐름계에서의 출력 EMF와의 차이를 아울러 검토하였다. 이러한 출력에서의 차이는 $CO_2$$O_2$의 분압과 분위기가스와 전극물질과의 비가역반응에 기인됨을 알았다.

  • PDF

SnO2 나노 분말의 합성 및 가스 감응 특성 (Gas Sensing Characteristics and Preparation of SnO2 Nano Powders)

  • 이지영;유윤식;유일
    • 한국전기전자재료학회논문지
    • /
    • 제24권7호
    • /
    • pp.589-593
    • /
    • 2011
  • [ $SnO_2$ ]nano powders were prepared by solution reduction method using tin chloride($SnCl_2{\cdot}2H_2O$), hydrazine($N_2H_4$) and NaOH. The $SnO_2$ thick films for gas sensors were fabricated by screen printing method on alumina substrates and annealed at $300^{\circ}C$ in air, respectively. XRD patterns of the $SnO_2$ nano powders showed the tetragonal structure with (110) dominant orientation. The particle size of $SnO_2$ nano powders at the ratio of $SnCl_2:N_2H_4$+NaOH= 1:6 was about 60 nm. The sensing characteristics were investigated by measuring the electrical resistance of each sensor in a test box. Sensitivity of $SnO_2$ gas sensor to 5 ppm $CH_4$gas and 5 ppm $CH_3CH_2CH_3$ gas was investigated for various $SnCl_2:N_2H_4$+NaOH proportion. The highest sensitivity to $CH_4$ gas and $CH_3CH_2CH_3$ gas of $SnO_2$ sensors was observed at the $SnCl_2:N_2H_4$+NaOH= 1:8 and $SnCl_2:N_2H_4$+NaOH= 1:6, respectively. Response and recovery times of $SnO_2$ gas sensors prepared by $SnCl_2:N_2H_4$+NaOH= 1:6 was about 40 s and 30 s, respectively.

무연 (Na1,K)NbO3 계 세라믹스를 이용한 AE센서의 감도특성 (Sensitivity Characteristics of Acoustic Emission(AE) Sensor using the Lead-free (Na1,K)NbO3 Ceramics)

  • 류주현;이갑수;홍재일
    • 한국전기전자재료학회논문지
    • /
    • 제20권3호
    • /
    • pp.218-222
    • /
    • 2007
  • In this study, Acoustic emission(AE) sensors were fabricated using lead-free piezoelectric ceramics for prohibiting environmental pollution. Structure of AE sensors were designed as Langvin type air backing form. Here, the piezoelectic element was used as PZT(EC-65)(AE1) and NKN(AE2), respectively. The measured resonant frequency, the maximum sensitivity frequency and sensitivity of AE sensors were as follows ; 143 kHz, 29.4 kHz and 69.3 dB in AE1 and 179 kHz, 29.4 kHz and 66.3dB in AE2, respectively.

콘크리트 구조물의 부식감시용 매설형 기준전극의 전기화학적 안정성에 관한 연구 (Embeddable reference sensors for corrosion monitoring in concrete structures)

  • 하태현;배정효;하윤철;이현구;김대경
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.160-163
    • /
    • 2005
  • Several sensors are involved in the cor개sion monitoring of concrete structures. This paper deals with the monitoring of concrete structures by embeddable reference sensors. $MnO_2$, MMO and graphite reference sensors are fabricated in the laboratory as suitable as embeddable type into the concrete structures. Sensors are embedded into the mortars and the performance was studied in the absence and presence of chloride ions. The electrochemical stability of the sensors was carried out for the exposure period of one year. Polarisation behaviour and impedance of the sensors in mortar was carried out in three aqueous solutions namely distilled water, 3% NaCl and natural sea water.

  • PDF

센서 배열의 보정에 의한 자기 부상 시스템의 외란 제거 성능 개선 (Disturbance Elimination Performance Improvement of A Magnetic Levitation System by Array-Sensor Calibration)

  • 안명국;나승유
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
    • /
    • pp.278-281
    • /
    • 2002
  • In this paper we propose a controller which has the capability of disturbance measurement calibration for Cds array sensors in a magnetic levitation system. Steady state error due to environment light condition or external disturbance is corrected constantly. The correction is made by the sensors to measure the ball position of the system without additional deployment of sensors.

  • PDF