• 제목/요약/키워드: TEA transport

검색결과 39건 처리시간 0.026초

Zn2SnSe6 및 Zn4SnSe6:Co2+(0.5mol%) 단결정에서 열역학적 함수의 온도의존성 (Temperature dependence of thermodynamic function in Zn4SnSe6 and Zn4SnSe6:Co2+(0.5mol%) single crystals)

  • 김남오;김형곤;김덕태;송호준
    • 전기학회논문지P
    • /
    • 제52권2호
    • /
    • pp.68-73
    • /
    • 2003
  • $Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals were grown by the chemical transport reaction(CTR) method. They were crystallized in the monoclinic structure. These temperature dependence of the optical energy gap were closely investigated over the temperature range 10[K]~300[K]. The direct energy gaps of $Zn_4SnSe_6$ and $Zn_4SnSe_6$:$Co^{2+}$ single crystals were given by 2.146[eV] and 2.042[eV] at 300[K]. The temperature dependence of the optical energy gap is well presented by the Varshni equation.

Development of a Human Mammary Epithelial Cell Culture Model for Evaluation of Drug Transfer into Milk

  • Kimura Soichiro;Morimoto Keiko;Okamoto Hiroshi;Ueda Hideo;Kobayashi Daisuke;Kobayashi Jun;Morimoto Yasunori
    • Archives of Pharmacal Research
    • /
    • 제29권5호
    • /
    • pp.424-429
    • /
    • 2006
  • In the present study, a human mammary epithelial cell (HMEC) culture model was developed to evaluate the potential involvement of carrier-mediated transport systems in drug transfer into milk. Trypsin-resistant HMECs were seeded on $Matrigel^{circledR}-coated$ filters to develop monolayers of functionally differentiated HMEC. Expression of the specific function of HMEC monolayers was dependent of the number of trypsin treatments. Among the monolayers with different numbers of treatment (treated 1 to 3 times), the monolayer treated 3 times (3-t-HMEC monolayer) showed the highest maximal transepithelial resistance and expression of $\beta-casein$ mRNA as an index of differentiation. Transport of tetraethylammonium (TEA) across the 3-t-HMEC monolayer in the basolateral-to-apical direction was significantly higher than that in the apical-to-basolateral direction (p<0.05), whereas such directionality was not observed for p-aminohippurate, suggesting the existence of organic cation transporters, but not organic anion transporters. In fact, expression of mRNAs of human organic cation transporter (OCT) 1 and 3 were detected in the 3-t-HMEC monolayer. These results indicate that the 3-t-HMEC monolayer is potentially useful for the evaluation of carrier-mediated secretion of drugs including organic cations into human milk.

화물전기기관차 차체개발 (Development of Carbody Structure for Freight Electric Locomotives)

  • 최원호;곽태호;김구식
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
    • /
    • pp.2635-2643
    • /
    • 2011
  • Current freight electric locomotives (132 ton) of the eco-friendly and can carry large cargo logistics as a means of generation has increased the demand at home and abroad. Especially, Freight electric locomotives to increase the traction, it is easy to mass and rapid transport. In addition, Freight electric locomotives is no exhaust and low noise compared to diesel -electric locomotives and it can be eco-friendly transportation. CO_CO BOGIE of Freight electric locomotives has no the center pivot and Traction_Rod and Spring of CO_CO BOGIE is mounted on the body. These freight electric locomotives to be satisfied with the safety regulations. Carbody development satisfied Implementation of optimum body and collision is the focus. Accordingly, the different approach in the upper and lower carbody structure and interior and equipment placement is needed. On this paper, the contents give explanation of cases on carbody design composed of freight electric locomotives now developed and process of improvement by structure analysis and collision analysis.

  • PDF

$H_2O_2$에 의한 신장(腎臟) 세포 손상에 대한 단삼(丹參) 추출물의 방지 효과 (Protective effect of Salviae-radix extraction in $H_2O_2$ induced renal cell injury)

  • 김상범;정지천
    • 대한한의학회지
    • /
    • 제19권1호
    • /
    • pp.38-48
    • /
    • 1998
  • This study was undertaken to determine whether Salviae-radix (SVR) extraction prevents the oxidant-induced cell injury and thereby exerts protective effect against oxidant-induced inhibition of tetraethylammonium uptake (TEA) in renal corticaJ sices. SVR (5%) attenuated $H_2O_2-induced$ inhibition of TEA uptake. $H_2O_2$ increased LDH release and lipid peroxidation in a dose-dependent manner. These changes were prevented by SVR extraction. The protective effect of SVR on LDH release was dose-dependent over the concentration range of 0.1-0.5%, and that on lipid peroxidation over the concentration ranges of 0.05-2%. SVR significantly prevented Hg-induced lipid peroxidation. SVR extraction (0.5%) increased cellular GSH content in normal and $H_2O_2-treated$ tissues. When slices were treated with 100 mM $H_2O_2$, catalase activity was decreased, which was prevented by 0.5% SVR extraction. The activity of glutathione peroxidase but not superoxide dismutase was significantly increased by 0.5% SVR extraction in $H_2O_2-treated$ tissuces. These results suggest that SVR has an antioxidant action and thereby exerts benefical effect against oxidant-induced impairment of membrane transport function. This effect of SVR is attributed to an increase in endogenous antioxidants such as GSH, catalase and glutathione peroxidase.

  • PDF

홍화자약침액(紅花子藥鍼液)이 수은(水銀)에 의한 가토(家兎)의 신세뇨관(腎細尿管) 물질이동(物質移動) 변화(變化)에 미치는 영향(影響) (Effect of Carthami Semen Aquacupunture(CSA) on Mercury-Induced Alterations in Tubular Transport Function in Rabbits)

  • 최영규;윤현민;송춘호;장경전;안창범
    • Journal of Acupuncture Research
    • /
    • 제19권5호
    • /
    • pp.199-208
    • /
    • 2002
  • Objective : This study was undertaken to determine if Carthami Semen Aquacupunc- ture(CSA) exerts protective effect against alterations in membrane transport function rabbits with mercury chloride(HG)-induced acute renal failure. Methods : The administration of Hg at a subcutaneous single dose of 10 mg/kg caused a reduction in GFR and an increase in fractional Na excretion, indicating generation of acute renal failure. When CSA were given for 7 days prior to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased in rabbits treated with Hg alone. Results : The increase in rabbits treated with Hg following CSA are significantly lower than that in animals treated with Hg alone. Uptakes of glucose and phosphate in purified isolated brush-border membrane and Na-K-ATPase activity in microsomal fraction were inhibited in rabbits treated with Hg alone. Such changes were prevented by CSA. Uptakes of organic ions, PAH and TEA, in renal cortical slices were inhibited by the administration of Hg, which was prevented by CSA. Exposure of renal cortical slices to Hg in vitro caused an increased LDH release and lipid peroxidation, which was significantly prevented by CSA extract. Conclusions : These results indicate that the administration of Hg causes impairment in reabsorption of solutes in the proximal tubule via the generation of reactive oxygen species. CSA provides the protection against the impairment in proximal reabsorption, and its effect may be resulted from its antioxidant effect.

  • PDF

TCS 자료를 이용한 강설과 고속도로 통행특성 관계 연구 (Analysis of Snowing Impacts on Freeway Trip Characteristics Using TCS Data)

  • 백승걸;정소영;이태경;원제무
    • 한국ITS학회 논문지
    • /
    • 제9권4호
    • /
    • pp.68-79
    • /
    • 2010
  • 기상조건은 도로 및 운전조건을 열악하게 함으로써 교통사고와 정체의 원인이 되며, 운전자의 통행선택에 영향을 미쳐 기종점통행특성도 변화시킨다. 기종점 통행량은 교통계획에 있어 필수적으로 요구되는 자료이지만, 기상조건과 통행량과의 관련성을 검토한 연구는 거의 없는 실정이다. 본 연구는 강설조건이 기종점간 통행특성에 미치는 영향을 분석한 연구로, 1998년-2008년 기상자료와 TCS 통행량 자료를 이용하여 강설일과 비강설일의 차종별 일통행량, 평균통행거리를 비교 분석하였으며, 강설수준별 통행량 관계를 제시하였다. 분석결과 강설일 대비 비강설일의 통행량은 감소하며, 통행거리도 감소한다는 것을 확인하였으며. 강설시 주말/평일별 차종별로 통행특성의 차이가 있고, 강설수준에 따른 통행량의 차이도 있으나 그 정도는 크지 않다는 것을 제시하였다.

GIS 공간 분석기법을 통한 철도사고위험물질별 피해규모 자동추출방안 (A Method to Measure Damage Areas by the types of Railroad Hazardous Material through GIS Spatial Analysis)

  • 김상균;김시곤;이원태
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2009년도 춘계학술대회 논문집
    • /
    • pp.1769-1778
    • /
    • 2009
  • 산업의 발달 및 도시화의 증가로 인해 위험물질을 포함한 물류 수송량은 날로 증가하는 추세이고 위험물질 수송차량들의 사고발생 위험도 따라서 증대되고 있다. 본 연구에서는 위험물 운송이 점차 증가하고 있는 철도수송에 있어 기존 선행 연구의 피해규모 분석모형을 적용하고, 위험물 물류 표준화 연구에서 정의된 물질별 사고노출량을 기준으로 하여 위험물 물질별 인구 및 환경 노출규모를 GIS(Geographic Information System)의 버퍼링 분석 기 법을 통하여 일반적으로 분석이 어려운 피해규모산정을 자동으로 도출하는 방안을 제시하였다. 각 링크별 인구 및 노출규모 산출 모형을 적용하기 위해서는 Network(철도망), Zone(행정구역), 철도사고 Data, 철도화물 통행량, 하천 및 강 등을 GIS Database로 구축하였고, 최종적으로 Buffering 분석과 함께, 중첩분석의 Clip 기법과 Special Join 기법을 함께 사용하여 본연구의 제시한 위험물 물질별 피해규모 자동 추출 방안을 제시해 보았다.

  • PDF

단삼약침(丹蔘藥鍼)이 급성신부전(急性腎不全) 가토(家兎)의 신세뇨관(腎細尿管)에 미치는 영향(影響) (Effect of Salviae Radix herb-acupuncture on rabbits with Hg-induced acute renal failure)

  • 임춘우;서정철;윤현민;장경전;송춘호;안창범
    • Journal of Acupuncture Research
    • /
    • 제18권2호
    • /
    • pp.111-122
    • /
    • 2001
  • Objectives ; This study was undertaken to determine if Salviae Radix herb-acupuncture (SRA) exerts protective effect against alterations in membrane transport function in rabbits with mercury chloride (Hg)-induced acute renal failure. Methods and Results ; The administration of Hg at a subcutaneous single dose of 10mg/kg caused a reduction in GFR to 9.4% of the basal value and an increase in fractional Na+ excretion to 10-fold, indicating generation of acute renal failure. When animals were acupunctured with $0.5m{\ell}$ of SRA extract (0.1%) in both sides of Shinsu(BL23) for 7 days prod to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased to approximately 132-fold and 7-fold, respectively, in rabbits treated with Hg alone, but the fractional excretion of glucose was increased to 26-fold and that of phosphate was not different from the basal value in SRA-pretreated rabbits. Uptakes of glucose and phosphate in purified isolated brush-border membrane and $Na^+-K^+$-ATPase activity in microsomal fraction were inhibited in rabbits treated with Hg alone, suggesting that impairment in proximal reabsorption of glucose and phosphate is resulted from a direct damage of membrane transport carriers and disruption of the normal $Na^+$ gradient. Conclusions ; Such changes were prevented by SRA. Uptakes of organic ions, PAH and TEA, in renal cortical slices were inhibited by the administration of Hg, which was prevented by SRA. Pretreatment of an antioxidant DPPD attenuated the increase in the fractional excretion of glucose and phosphate induced by the administration of Hg.

  • PDF

A Review: Influences of Pre-slaughter Stress on Poultry Meat Quality

  • Ali, Md. Shawkat;Kang, Geun-Ho;Joo, Seon Tea
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제21권6호
    • /
    • pp.912-916
    • /
    • 2008
  • Pre-slaughter conditions affect poultry meat quality. Therefore, stresses before slaughter like heat stress, struggle and shackling on the shackle line, crating and transport and feed withdrawal are very important for the poultry industry in respect of quality as well as welfare of the birds. However, exposure to heat in oxidative stress can in turn lead to cytotoxicity in meat type birds. Chickens exposed to heat stress before slaughter showed the lowest ultimate pH and birds shackled for a longer time the highest. The abdominal fat content was higher in heat stressed birds. Struggling on the shackle line hastened the initial rate of the pH drop and increased the redness of breast meat. Again, with increasing struggling activity, lactate concentration in breast muscle of chicken increased. Paler meat was found in birds that were transported for a longer time than in those after a small journey or not transported. The pre-slaughter and eviscerated weights were decreased as the length of feed withdrawal period increased.

무선 센서 네트워크를 위한 네트워크 환경에 적응하는 신뢰성 있는 전송규약 (A network condition adaptive reliable transport protocol for wireless sensor networks)

  • 임근수;박정태;고건
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (C)
    • /
    • pp.277-279
    • /
    • 2003
  • 본 논문에서는 편재 컴퓨팅(ubiquitous and pervasive computing) 환경에 입력 시스템으로 사용하는 센서 네트워크에서 측정한 데이터의 품질 (sampling rate and quantization depth) 을 보증하며 네트워크 트래픽 또는 소모전력과 같은 비용을 최소화하기 위한 방법으로, 휴리스틱 알고리즘에 의한 비주기적 샘플링과 신뢰성 있는 전송규약을 사용하는 비주기적 전송방식을 제안한다. 그리고 제안한 비주기적 전송방식에 핵심기술인 신뢰성 있는 전송 규약의 비용을 최적화하기 위한 방법으로 ACK방식과 NACK방식을 패킷 에러율과 동일한 라우터를 사용하는 이웃 노드의 수와 같은 네트워크 상황에 따라 상보적으로 사용하는 상보적 방식(alternative method)을 제안하고, 전체 통신규약을 설계하며, 해석을 통해 성능을 분석하고, 네트워크 상태에 따라 두 방식의 성능상의 우열이 전환되는 전환점을 유도한다. 제안하는 상보형 신뢰성 있는 전송규약은 전체 센서 네트워크에서 처리되는 패킷의 비트 수를 최소화해, 각 노드의 총 전력 소모의 20-60%를 차지하는 통신모듈의 소비 전력을 줄일 수 있어 전력소모를 크게 개선 할 수 있다. 나아가서 다양한 센서 네트워크에서 설계한 전송규약을 바탕으로 하는 제안하는 비주기적 전송방식을 활용한다면 최적의 비용으로 측정하는 데이터의 품질을 보증할 수 있다.

  • PDF