• 제목/요약/키워드: Differential shortening

검색결과 49건 처리시간 0.02초

혼화재료 혼입 콘크리트 강도 차에 따른 건조수축 및 크리프 특성 평가 (Evaluation of Drying Shrinkage and Creep Characteristics by Strength Differences of Concrete Mixed with Admixture)

  • 박동천;송화철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.199-200
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    • 2021
  • In the study, creep and dry shrinkage characteristics were evaluated to determine the material properties necessary for structural analysis such as column shortening and differential drying shrinkage. All the experiments were conducted in an constant temperature and humidity room. The mechanical properties as well as the specific creep and ultimate dry shrinkage values were derived. In addition the characteristics of the physical value of the high-strength fiber reinforced concrete were considered.

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Differential Localisation of PARP-1 N-Terminal Fragment in PARP-1+/+ and PARP-1-/- Murine Cells

  • Rajiah, Ida Rachel;Skepper, Jeremy
    • Molecules and Cells
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    • 제37권7호
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    • pp.526-531
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    • 2014
  • Human PARP family consists of 17 members of which PARP-1 is a prominent member and plays a key role in DNA repair pathways. It has an N-terminal DNA-binding domain (DBD) encompassing the nuclear localisation signal (NLS), central automodification domain and C-terminal catalytic domain. PARP-1 accounts for majority of poly-(ADP-ribose) polymer synthesis that upon binding to numerous proteins including PARP itself modulates their activity. Reduced PARP-1 activity in ageing human samples and its deficiency leading to telomere shortening has been reported. Hence for cell survival, maintenance of genomic integrity and longevity presence of intact PARP-1 in the nucleus is paramount. Although localisation of full-length and truncated PARP-1 in PARP-1 proficient cells is well documented, subcellular distribution of PARP-1 fragments in the absence of endogenous PARP-1 is not known. Here we report the differential localisation of PARP-1 Nterminal fragment encompassing NLS in PARP-$1^{+/+}$ and PARP-$1^{-/-}$ mouse embryo fibroblasts by live imaging of cells transiently expressing EGFP tagged fragment. In PARP-$1^{+/+}$ cells the fragment localises to the nuclei presenting a granular pattern. Furthermore, it is densely packaged in the midsections of the nucleus. In contrast, the fragment localises exclusively to the cytoplasm in PARP-$1^{-/-}$ cells. Flourescence intensity analysis further confirmed this observation indicating that the N-terminal fragment requires endogenous PARP-1 for its nuclear transport. Our study illustrates the trafficking role of PARP-1 independently of its enzymatic activity and highlights the possibility that full-length PARP-1 may play a key role in the nuclear transport of its siblings and other molecules.

Wilshire Grand: Outrigger Designs and Details for a Highly Seismic Site

  • Joseph, Leonard M.;Gulec, C. Kerem;Schwaiger, Justin M.
    • 국제초고층학회논문집
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    • 제5권1호
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    • pp.1-12
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    • 2016
  • The 1100 foot [335 m] tall Wilshire Grand Center tower under construction in Los Angeles illustrates many key outrigger issues. The tower has a long, narrow floor plan and slender central core. Outrigger braces at three groups of levels in the tower help provide for occupant comfort during windy conditions as well as safety during earthquakes. Because outrigger systems are outside the scope of prescriptive code provisions, Performance Based Design (PBD) using Nonlinear Response History Analysis (NRHA) demonstrated acceptability to the Los Angeles building department and its peer review panel. Buckling Restrained Brace (BRB) diagonals are used at all outrigger levels to provide stable cyclic nonlinear behavior and to limit forces generated at columns, connections and core walls. Each diagonal at the lowest set of outriggers includes four individual BRBs to provide exceptional capacities. The middle outriggers have an unusual 'X-braced Vierendeel' configuration to provide clear hotel corridors. The top outriggers are pre-loaded by jacks to address long-term differential shortening between the concrete core and concrete-filled steel perimeter box columns. The outrigger connection details are complex in order to handle large forces and deformations, but were developed with contractor input to enable practical construction.

An Ultra-precision Electronic Clinometer for Measurement of Small Inclination Angles

  • Tan, Siew-Leng;Kataoka, Satoshi;Ishikawa, Tatsuya;Ito, So;Shimizu, Yuuki;Chen, Yuanliu;Gao, Wei;Nakagawa, Satoshi
    • 한국생산제조학회지
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    • 제23권6호
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    • pp.539-546
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    • 2014
  • This paper describes an ultra-precision electronic clinometer, which is based on the capacitive-based fluid type, for detection of small inclination angles. The main parts of the clinometer low-noise electronics are two capacitance measurement circuits for converting the capacitances of the capacitors of the clinometer into voltages, and a differential amplifier for obtaining the difference of the capacitances, which is proportional to the input inclination angle. A 16 bit analog to digital (AD) converter is also embedded into the same circuit board, whose output is sent to a PC via RS-232C, for achieving a small noise level down to tens of ${\mu}v$. A compensation method, which is referred to as the delay time method for shortening the stabilization time of the sensor was also discussed. Experimental results have shown the possibility of achieving a measurement resolution of $0.0001^{\circ}$ as well as the quick measurement with the delay time method.

Endothelin Receptor Overexpression Alters Diastolic Function in Cultured Rat Ventricular Myocytes

  • Kang, Mi-Suk;Walker, Jeffery W.;Chung, Ka-Young
    • Biomolecules & Therapeutics
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    • 제20권4호
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    • pp.386-392
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    • 2012
  • The endothelin (ET) signaling pathway controls many physiological processes in myocardium and often becomes upregulated in heart diseases. The aim of the present study was to investigate the effects of ET receptor upregulation on the contractile function of adult ventricular myocytes. Primary cultured adult rat ventricular myocytes were used as a model system of ET receptor overexpression in the heart. Endothelin receptor type A ($ET_A$) or type B ($ET_B$) was overexpressed by Adenoviral infection, and the twitch responses of infected ventricular myocytes were measured after ET-1 stimulation. Overexpression of $ET_A$ exaggerated positive inotropic effect (PIE) and diastolic shortening of ET-1, and induced a new twitch response including twitch broadening. On the contrary, overexpression of $ET_B$ increased PIE of ET-1, but did not affect other two twitch responses. Control myocytes expressing endogenous receptors showed a parallel increase in twitch amplitude and systolic $Ca^{2+}$ in response to ET-1. However, intracellular $Ca^{2+}$ did not change in proportion to the changes in contractility in myocytes overexpressing $ET_A$. Overexpression of $ET_A$ enhanced both systolic and diastolic contractility without parallel changes in $Ca^{2+}$. Differential regulation of this nature indicates that upregulation of $ET_A$ may contribute to diastolic myocardial dysfunction by selectively targeting myofilament proteins that regulate resting cell length, twitch duration and responsiveness to prevailing $Ca^{2+}$.

결정화에 의한 4성분계 에너지 복합체 제조 및 열분해 특성 (Preparation of Quaternary Energetic Composites by Crystallization and Their Thermal Decomposition Characteristics)

  • 김병수;김재경;안익성;김현수;구기갑
    • 공업화학
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    • 제30권2호
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    • pp.178-185
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    • 2019
  • 결정화/응집 공정을 이용하여 금속/금속산화물/분자화약/산화제로 구성된 구형 4성분계 복합체 3종을 제조하였다. 열중량 분석(TGA) 및 시차주사열량법(DSC)에 의한 열 특성 분석 결과 복합체를 이룬 분자화약의 분해 구간이 단축됨을 관찰하였고, ammonium perchlorate(AP) 분해 생성물인 HCl 및 $ClO_2$에 의한 자가 촉매 반응에 의한 것으로 해석된다. 활성화 에너지 분석 결과 분자화약 분해 종료 구간에서 급격하게 활성화 에너지가 감소함을 확인할 수 있었으며, 이는 분자화약 분해 생성물 중 공통으로 발생하는 $HNO_2$에 의한 것으로 판단된다. 본 연구에서 복합체 열분해 분석 결과로부터 Distributed Activation Energy Model (DAEM)에 의해 모사된 활성화 에너지가 model-fitting 분석법인 Kissinger-Akahira-Sunose와 Flynn-Wall-Ozawa model에 의한 모사치보다 정확도가 대단히 우수함을 알 수 있었다.

초고층 건물의 시공 중 구조적 안정성 검토를 위한 시공단계해석의 적용 (An Application of Construction Sequence Analysis for Checking Structural Stability of High-Rise Building under Construction)

  • 엄태성;김재요
    • 한국전산구조공학회논문집
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    • 제22권3호
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    • pp.211-221
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    • 2009
  • 극초고층성, 비정형 형상, 공기단축을 위한 구획 시공 등 최근 초고층 건물의 경향을 고려할 때, 설계 및 시공 계획의 단계에서 시공 중 건물의 구조적 안정성 문제가 핵심 사항으로 부각되고 있다. 시공 중 초고층 건물의 안정성을 확보하기 위해서는 횡력저항시스템이 완전히 형성되기 전 구조체 자중의 불균형 분포에 의해 발생하는 수직부재의 불균등 축소, 골조의 기울어짐 혹은 횡변위, 기초의 부등 침하 등이 시공단계해석에 의하여 검토되어야 하며, 시공단계해석은 구조건전성모니터링, 시공 보정 프로그램, 시공계획 수립 등과 체계적으로 결합되어 진행되어야 한다. 이 논문은 시공 중 초고층 건물의 구조 안정성 검토를 위하여 기존의 범용구조해석프로그램을 활용한 구역 기반 시공단계해석 기법을 제시하고 있으며, 이를 실제 초고층 프로젝트의 3차원 구조해석에 적용하였다. 정밀한 해석을 위하여 시간 의존적 재료 성질 및 실제 시공 일정이 적용되었으며, 시공 일정 변화나 계측 결과와의 비교에 따른 재료 물성 변화 등을 지속적으로 변경하며 해석이 진행되었다. 이러한 실제 프로젝트에 대한 시공단계해석 적용을 통하여, 시공 중 초고층 건물의 안정성 확보를 위한 주요 검토 항목 및 방법을 제시하였다.

Differential Diagnosis of Chemical-induced Hepatobiliary Toxicities Using a New Hepatobiliary Imaging Agent in Mice

  • Ryu, Chong-Kun;Pie, Jae-Eun;Choe, Jae-Gol;Cheon, Joon;Sohn, Jeong-Won;Jurgen Seidel;David S. Paik;Michael V. Green;Chang H. Paik;Kim, Meyoung-Kon
    • 한국환경성돌연변이발암원학회지
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    • 제21권1호
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    • pp.1-8
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    • 2001
  • We have synthesized $^{99m}$Tc-mercaptoacetyltriglycine (MAG3)-biocytin as a new imaging agent for hepatobiliary scintigraphy. The aim of this study was to evaluate the usefulness of $^{99m}$Tc-MAG3-biocytin scintigraphy in differentiating carbon tetrachloride ( $CCl_4$)-induced hepatotoxicity from $\alpha$-naphthylisothiocyanate (ANIT)-induced cholestasis in mice, which reflecting the differential diagnosis of neonatal jaundice caused by neonatal hepatitis from congenital biliary atresia in humans. Methods: Balb/c mice (female, 20 g, n=4-6) were pretreated with $CCl_4$(0.5 or $1.0m\ell$/kg) and ANIT ($150 or 300 m\ell$/kg) 18 h before scintigraphy. Biochemical and histopathological examinations showed a pattern of typical acute hepatitis (increase of transaminases and hepatocellular necnsis) in $CCl_4$-treated mice and cholestasis (increase of alkaline phosphatase and ${\gamma}$-glutamyltransferase, and biliary hyperplasia) in ANIT-treated mice, respectively, Mice were fasted at least 4 hr prior to the intravenous injection of $^{99m}$Tc-MAG3-biocytin (18.5 MBq/20$\mu\textrm{g}$) in 2% human serum albumin in saline. Scintigraphy was performed with a ${\gamma}$-camera equipped with a 1-mm diameter pin-hole collimator for 30 min and images were acquired every 15 s. We compared the values of physical parameters, such as peak liver/heart ratio ($${\gamma}$_{max}$) and peak ratio time ($t_{max}$) far $^{99m}$Tc-MAG3-biocytin scintigraphy. Results: Scintigraphic parameters of the $CCl_4$-pretreated (0.5 $m\ell$/kg) group showed a 81.9% decrease of r$_{max}$, and 42.2% decrease of $t_{max}$, whereas the ANIT-pretreated ( $150m\ell$/kg) group showed a 53% decrease of $r_{max}$, and 2.36-fold increase of $t_{max}$, (P<0.05). These results demonstrate that the decrease of $r_{max}$ and the shortening of $t_{max}$ are characteristic features for hepatotoxicity, in contrast to the increase of $t_{max}$ and decrease of $r_{max}$ for biliary hyperplasia. Conclusion: $^{99m}$Tc-MAG3-biocytin hepatobiliary scintigraphy can distinguish hepatitis from cholestasis in mice model and may be similarly useful in humans which differentiating the cause of neonatal jaundice in clinical study.cal study.cal study.cal study.

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부산지역에서 옥천변성대의 지질구조: 하트상 부산 편마암복합체에 대한 새로운 지구조모델 (Geological structure of the Ogcheon metamorphic zone in the Busan areal Korea: a new geodynamic model to the Heart-shaped Busan gneiss complex)

  • 강지훈
    • 암석학회지
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    • 제10권2호
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    • pp.106-120
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    • 2001
  • 옥천변성대의 북동부에 위치하는 부산지역은 주로 선캠브리아대 부산 및 박달령 편마암복합체와 옥천변성암류 그리고 중생대 화강암류 등으로 구성되어 있다. 부산지역의 중앙부에 위치하고 주변부가 옥천변성암류에 의해 둘러싸여 있는 부산 편마암복합체는 마치 동쪽으로 누운 하트상 분포를 하고 있다. 본 연구는 부산지역에서 옥천변성대의 지질구조를 규명하기 위하여 부산지역의 주요 구성암류인 부산 편마암복합체와 옥천변성암류에 대한 변형 단계별 암석구조와 변형 단계별 구조요소들의 영역별 방향성 변화와 발달정도를 연구하였다. 그 결과, 부산지역에서 옥천변성대의 지질구조는 적어도 세 번의 변형단계를 거쳐 형성되었음을 알게 되었다. (1) D1 변형: 북북동-남남서 방향의 압축작용과 관련된 압쇄면과 서북서 방향의 지구조단위들(산저터, 부산-II, 부산-I, 충주 나페들)의 형성기, (2) D2 변형: 동-서 내지 서북서-동남동 방향의 압축작용과 관련된 서북서 방향의 지구조단위들의 차별적인 동서추축기와 남북신장기, (3) D3 변형: D2 변형에 의해 남북 내지 북북동 방향으로 재배열된 부산지역 동부와 남부 지구조단위들의 남북 방향의 압축작용과 관련된 동서 방향의 킹크 및 개방습곡 형성기. 이러한 세 번의 변형작용은 부산지역에서 옥천변성대의 지구조단위들과 동쪽으로 누운 하트상 부산 편마암복합체의 분포와 밀접한 연관성이 있으며, 본 논문에서는 이와 관련된 새로운 지구조모텔을 제시한다: Dl 변형-일정한 폭을 갖는 서북서 방향의 대상분포, D2 변형-북동향과 남향의 볼록한 쐐기모양 형성, D3 변형-서향의 오목한 쐐기모양 형성.

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