• Title/Summary/Keyword: Structural Breaks

Search Result 54, Processing Time 0.021 seconds

BAF53 is Critical for Focus Formation of $\gamma$-H2AX in Response to DNA Damage

  • Park, Pan-Kyu;Kang, Dong-Hyun;Kwon, Hyock-Man
    • Animal cells and systems
    • /
    • v.13 no.4
    • /
    • pp.405-409
    • /
    • 2009
  • When DNA double-strand breaks (DSBs) were induced in mammalian cells, many DNA damage response proteins are accumulated at damage sites to form nuclear foci called IR-induced foci. Although the formation of foci has been shown to promote repair efficiency, the structural organization of chromatin in foci remains obscure. BAF53 is an actin-related protein which is required for maintenance of chromosome territory. In this study, we show that the formation of IR-induced foci by $\gamma$-H2AX and 53BP1 were reduced when BAF53 is depleted, while DSB- activated ATM pathway and the phosphorylation of H2AX remains intact after DNA damage in BAF53 knockdown cells. We also found that DSB repair efficiency was largely compromised in BAF53 knockdown cells. These results indicate that BAF53 is critical for formation of foci by $\gamma$-H2AX decorated chromatin at damage sites and the structural organization of chromatin in foci is an important factor to achieve the maximum efficiency of DNA repair.

Experiment and Analysis of Load-Bearing Insulations for Slabs Thermal Breaks composed by H-Shaped Stainless Steel and UHPC Blocks (H강재와 UHPC압축블록을 적용한 슬래브용 열교차단 단열구조체 실험 및 해석연구)

  • Kim, Jae Young;Lee, Ga Yoon;Yoo, Young Jong;An, Sang Hee;Lee, Kihak
    • Journal of Korean Association for Spatial Structures
    • /
    • v.23 no.3
    • /
    • pp.35-43
    • /
    • 2023
  • This study aims to evaluate the structural safety of a structural thermal barrier, installed inside the structure of a building and performed the role of a load-bearing element and an insulation simultaneously, contributing to the realization of net-zero buildings. To ensure the reliability of the analysis model, the analysis results derived from LS-DYNA were compared with the experimental results. Based on the results shown through the flexural experiment, the reliability of the thermal cross-section insulation structure model for slabs was validated. In addition, the effect of the UHPC block on the load support performance and its contribution to vertical deflection was verified.

Identification of Meiotic Recombination Intermediates in Saccharomyces cerevisiae (효모 감수분열과정에서의 유전자 재조합 기전 특이적 DNA 중간체의 구조 변화)

  • Sung, Young Jin;Yoon, Sang Wook;Kim, Keun Pil
    • Korean Journal of Microbiology
    • /
    • v.49 no.1
    • /
    • pp.1-7
    • /
    • 2013
  • During meiosis, genetic recombinants are formed by homologous recombination accompanying with the programmed double-strand breaks (DSBs) and strand exchanges between homologous chromosomes. The mechanism is generated by recombination intermediates such as single-end invasions (SEIs) and double-Holliday junctions (dHJs), and followed by crossover (CO) or non-crossover (NCO) products. Our study was focused on the analysis of meiotic recombination intermediates (DSBs, SEIs, and dHJs) and final recombination products (CO and NCO). We identified these meiotic recombination intermediates using DNA physical analysis under HIS4LEU2 "hot spot" system in budding yeast, Saccharomyces cerevisiae. For DNA physical analysis, when the hot spot locus is recognized by restriction enzyme from synchronous meiotic cells, the fragmented DNA that are forming recombination intermediates can be detected and quantified through Southern hybridization analysis. Our study suggests that this system can analyze the structural change of recombination intermediates during DSB-SEI transition, double-Holiday junctions and crossover/non-crossover products in meiosis.

A Technique for Analyzing LSI Failures Using Wafer-level Emission Analysis System

  • Higuchi, Yasuhisa;Kawaguchi, Yasumasa;Sakazume, Tatsumi
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.1 no.1
    • /
    • pp.15-19
    • /
    • 2001
  • Current leakage is the major failure mode of semiconductor device characteristic failures. Conventionally, failures such as short circuit breaks and gate breakdowns have been analyzed and the detected causes have been reflected in the fabrication process. By using a wafer-level emission-leakage failure analysis method (in-line QC), we analyzed leakage mode failure, which is the major failure detected during the probe inspection process for LSIs, typically DRAMs and CMOS logic LSIs. We have thus developed a new technique that copes with the critical structural failures and random failures that directly affect probe yields.

  • PDF

Study on Disaster Prevention System for Long Span Bridge over the Sea (장대해상교량의 방재시스템 구축에 관한 연구)

  • Kong, Byung-Seung
    • Journal of Ocean Engineering and Technology
    • /
    • v.23 no.3
    • /
    • pp.59-64
    • /
    • 2009
  • Bridge types such as the suspension bridges and the cable stayed bridges maintained by cables present the dangerous possibility of a ship running through the bottom of the bridge. Due to hangers and main cables in the upper structural system, the bridge is also susceptible to disasters. However, these cable bridges are usually used for long span bridges over the sea. This structure is relatively more exposed to disasters, such as wind, hail, and earthquake, than other structures. This structure also has the potential to cause car accidents on account of the poor visibility due to foggy conditions. If a fire breaks out because of a car accident due to wind, a car explosion will likely occur.

Maritime Business Cycles with Multiple Structure Changes

  • Kim, Hyunsok
    • Journal of Navigation and Port Research
    • /
    • v.44 no.5
    • /
    • pp.407-413
    • /
    • 2020
  • In this paper we examined a novel extension of the convergence empirics for the maritime business cycle which considers structure breaks and/or changes. To provide theoretical justification, the convergence hypothesis uses the relaxed assumption to technology shocks. Based on the recent empirical results provided by Kim and Chang (2020), we consider nonlinear dynamics that capture the properties on structural changes in the equilibrium adjustment process. This approach bridges the gap between the theoretical framework and empirical specifications. In particular, we applied the convergence hypothesis to the multiple structure change model for the maritime business cycle. Our application to the maritime data showed support of the convergence hypothesis allowing multiple structure changes during the high volatile period and offers additional insight into the forecasting maritime business cycles.

(4+n)-noded Moving Least Square(MLS)-based finite elements for mesh gradation

  • Lim, Jae Hyuk;Im, Seyoung
    • Structural Engineering and Mechanics
    • /
    • v.25 no.1
    • /
    • pp.91-106
    • /
    • 2007
  • A new class of finite elements is described for dealing with mesh gradation. The approach employs the moving least square (MLS) scheme to devise a class of elements with an arbitrary number of nodal points on the parental domain. This approach generally leads to elements with rational shape functions, which significantly extends the function space of the conventional finite element method. With a special choice of the nodal points and the base functions, the method results in useful elements with polynomial shape functions for which the $C^1$ continuity breaks down across the boundaries between the subdomains comprising one element. Among those, (4 + n)-noded MLS based finite elements possess the generality to be connected with an arbitrary number of linear elements at a side of a given element. It enables us to connect one finite element with a few finite elements without complex remeshing. The effectiveness of the new elements is demonstrated via appropriate numerical examples.

Tree-Structured Nonlinear Regression

  • Chang, Young-Jae;Kim, Hyeon-Soo
    • The Korean Journal of Applied Statistics
    • /
    • v.24 no.5
    • /
    • pp.759-768
    • /
    • 2011
  • Tree algorithms have been widely developed for regression problems. One of the good features of a regression tree is the flexibility of fitting because it can correctly capture the nonlinearity of data well. Especially, data with sudden structural breaks such as the price of oil and exchange rates could be fitted well with a simple mixture of a few piecewise linear regression models. Now that split points are determined by chi-squared statistics related with residuals from fitting piecewise linear models and the split variable is chosen by an objective criterion, we can get a quite reasonable fitting result which goes in line with the visual interpretation of data. The piecewise linear regression by a regression tree can be used as a good fitting method, and can be applied to a dataset with much fluctuation.

Structural Breaks in the Securities markets (자본시장과 구조변화)

  • Rhee, Il-King
    • The Korean Journal of Financial Management
    • /
    • v.19 no.1
    • /
    • pp.1-32
    • /
    • 2002
  • 한국 종합주가지수는 한국증권거래소에 상장된 모든 기업들의 가치 가중치에 의한 포트폴리오의 가격의 시계열이라고 할 수 있다. 따라서 이 지수는 한국 경제의 현재의 활동과 미래의 활동에 대한 예상의 총합의 반영 또는 표상을 표현하는 정보라 할 수 있다. 본 논문에서는 시차변수가 독립변수로 도입될 수도 있으며, 시차변수가 아닌 변수가 독립변수로 도입되는 것이 허용되는 회귀모형을 통하여 구조변화의 회수와 구조변환점을 검정할 수 있는 통계량과 이 통계량의 확률분포를 분석하고 한국 종합주가지수에 적용하여 한국 종합주가 지수의 일별수익률에 구조변화가 발생하였는지의 여부와 발생했다면 발생회수와 변환점들을 발견하는데 그 목적이 있다. 한국 종합주가지수의 일별수익률은 분산의 변화 그리고 평균 및 분산의 동시변화가 1997년 9월 27일에 발생하였다. 자기회귀모형에 의할 때 증권시장의 구조변화는 1999년 11월 16일에 이루어졌다. 평균과 분산의 변화가 일어나 구조변화의 단계를 시작하고 구조변화에 알맞는 환경조성에 2년이 소요된 후에 1999년 11월 16일에 구조변화가 정착되었다. 정착이 이루어진 후에야 비로서 이 두 기간은 서로 다른 경제구조와 증권시장구조가 이루어지고 이에 입각하여 시장의 새로운 운동법칙이 전개되고 있다고 할 수 있을 것이다.

  • PDF

A Structural Characteristics of Hwatong-Connections in Traditional Mindori Type of Wood Structures (전통 민도리식 목구조 화통맞춤의 구조적 특성)

  • Yu, Hye-Ran;Kwon, Ki-Hyuk
    • Journal of architectural history
    • /
    • v.21 no.3
    • /
    • pp.7-28
    • /
    • 2012
  • This study is intended to Mindori structure which is general private houses' structural type among traditional types and is a basic study to confirm structural characteristics of Hwatong connection which is general connection type of column-beam-cross beam. It is aimed to analyze how main member, column, such as size, figure, thickness of Sungetuk and Dugeup affect on structure. Following conclusions are drawn. 1. According to connection conditions, models with big coefficient of friction show stable hysteretic behavior until the angle rotation of member reaches 1/60 and models with small coefficient of friction show dramatical increase in load after the angle rotation of member reaches 1/24. After the angle rotation of member reaches 1/30, separation distance of members is identified physically and cracks are not observed. 2. Specimens with big coefficient of friction show similar inner force regardless of column size(except column size 150mm) and models with small coefficient of friction show increasing inner force as the column size increases. Specimens with same sectional area have similar inner force even though the column figures are different. The thickness of Sungetuk and Dugeup doesn't affect inner force greatly, however, when the thickness of Sungetuk is thin, it could lead to failure of structure as it breaks. 3. The bigger the size of column and the coefficient of friction are, the smaller Bending stiffness depreciation ratio is. 4. Energy Dissipation Efficiency differs from the coefficient of friction. When the coefficient of friction is big, square column shows bigger than round one and it is bigger when the thickness of Sungetuk and Dugeup is thicker. When the coefficient of friction is small, round column shows bigger than square one.