• Title/Summary/Keyword: amplification factors

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Chromogenic In Situ Hybridisation Test for Breast Cancer Patients with Equivocal IHC Results - a Study from Iran

  • Mehrazma, Mitra;Kalantari, Elham;Rezvani, Hamid;Bahar, Babak;Basi, Ali;Razavi, Seyed Mohsen;Rakhshani, Nasser
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7695-7700
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    • 2015
  • Background: HER2/neu overexpression on cell membranes of breast cancer cells is due to HER2/neu gene amplification and it is important to identify potential candidates for anti HER2 therapy with trastuzumab. IHC, FISH and CISH are standard FDA approved assays currently used to determine HER2 status in routine practice. The aim of this study was to determine HER2 gene amplification, using the CISH method in breast carcinoma samples which had IHC +2 reactions. Materials and Methods: This study was conducted from 2008-2010 using 334 consecutive breast carcinoma samples referred from local laboratories to Mehr Hospital. CISH assays were performed for all cases, and IHC tests were also done for determining efficacy and accuracy of local labs. HER2 status in local IHC tests was compared with central IHC and CISH results. Results: Of 334 breast cancer patients, 16 were negative for HER2 IHC (0, +1), 201 cases were equivocal (+2), and 31 positive (+3). Of 334 referral cases, 88 were CISH positive (26.3%) and 246 were CISH negative (73.7%). Of 201 IHC +2 cases, HER2 gene amplification was observed in 42 cases (kappa: 0.42). A 29.9% concordance was found between local IHC and central IHC. Sensitivity and specificity of local IHC were 90% and 53.8%, respectively. Conclusions: Low accuracy of IHC results in local labs was associated with the following factors: using former FDA-approved criteria for HER2 interpretation, utilizing non-validated kits, and lack of any quality assurance program. Therefore, following the new 2014 ASCO/CAP guideline and comprehensive quality assurance should be implemented to ensure accuracy of HER2 testing.

Rapid Detection of Clostridium tetani by Recombinase Polymerase Amplification Using an Exo Probe

  • Guo, Mingjing;Feng, Pan;Zhang, Liqun;Feng, Chunfeng;Fu, Jie;Pu, Xiaoyun;Liu, Fei
    • Journal of Microbiology and Biotechnology
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    • v.32 no.1
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    • pp.91-98
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    • 2022
  • Tetanus is a potentially fatal public health illness resulted from the neurotoxins generated by Clostridium tetani. C. tetani is not easily culturable and culturing the relevant bacteria from infected wounds has rarely been useful in diagnosis; PCR-based assays can only be conducted at highly sophisticated laboratories. Therefore, a real-time recombinase polymerase amplification assay (Exo-RPA) was constructed to identify the fragments of the neurotoxin gene of C. tetani. Primers and the exo probe targeting the conserved region were designed, and the resulting amplicons could be detected in less than 20 min, with a detection limit of 20 copies/reaction. The RPA assay displayed good selectivity, and there were no cross-reactions with other infectious bacteria common in penetrating wounds. Tests of target-spiked serum and pus extract revealed that RPA is robust to interfering factors and has great potential for further development for biological sample analysis. This method has been confirmed to be reliable for discriminating between toxic and nontoxic C. tetani strains. The RPA assay dramatically improves the diagnostic efficacy with simplified device architecture and is a promising alternative to real-time PCR for tetanus detection.

Emulsion PCR Improves the Specificity and Sensitivity of PCR-based Pathogen Detection (식중독균 검출의 민감도 향상을 위한 Emulsion PCR 적용)

  • Chai, Changhoon
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.1
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    • pp.43-49
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    • 2016
  • Emulsion PCR (ePCR) has recently gained interest in the areas of food safety and biotechnology owing to its highly specific and sensitive performance in the amplification of target DNA. To facilitate the applications of ePCR to food safety and biotechnology, this paper describes the principles of ePCR and the factors that should be considered in designing ePCR. In addition, current research and applications related to ePCR are discussed.

Development of Earthquake Damage Estimation System and its Result Transmission by Engineering Test Satellite for Supporting Emergency

  • Jeong, Byeong-Pyo;Hosokawa, Masafumi;Takizawa, Osamu
    • 한국방재학회:학술대회논문집
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    • 2011.02a
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    • pp.12-19
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    • 2011
  • Drawing on its extensive experience with natural disasters, Japan has been dispatching Japan Disaster Relief (JDR) team to disaster-stricken countries to provide specialist assistance in rescue and medical operations. The JDR team has assisted in the wake of disasters including the 2004 Indian Ocean Earthquake and the 2008 Sichuan Earthquake in China. Information about the affected area is essential for a rapid disaster response. However, it can be difficult to gather information on damages in the immediate post-disaster period. To help overcome this problem, we have built on an Earthquake Damage Estimation System. This system makes it possible to produce distributions of the earthquake's seismic intensity and structural damage based on pre-calculated data such as landform and site amplification factors for Peak Ground Velocity, which are estimated from a Digital Elevation Model, as well as population distribution. The estimation result can be shared with the JDR team and with other international organizations through communications satellite or the Internet, enabling more effective rapid relief operations.

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Dynamic response of Euler-Bernoulli beams to resonant harmonic moving loads

  • Piccardo, Giuseppe;Tubino, Federica
    • Structural Engineering and Mechanics
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    • v.44 no.5
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    • pp.681-704
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    • 2012
  • The dynamic response of Euler-Bernoulli beams to resonant harmonic moving loads is analysed. The non-dimensional form of the motion equation of a beam crossed by a moving harmonic load is solved through a perturbation technique based on a two-scale temporal expansion, which permits a straightforward interpretation of the analytical solution. The dynamic response is expressed through a harmonic function slowly modulated in time, and the maximum dynamic response is identified with the maximum of the slow-varying amplitude. In case of ideal Euler-Bernoulli beams with elastic rotational springs at the support points, starting from analytical expressions for eigenfunctions, closed form solutions for the time-history of the dynamic response and for its maximum value are provided. Two dynamic factors are discussed: the Dynamic Amplification Factor, function of the non-dimensional speed parameter and of the structural damping ratio, and the Transition Deamplification Factor, function of the sole ratio between the two non-dimensional parameters. The influence of the involved parameters on the dynamic amplification is discussed within a general framework. The proposed procedure appears effective also in assessing the maximum response of real bridges characterized by numerically-estimated mode shapes, without requiring burdensome step-by-step dynamic analyses.

Aluminum and E-glass epoxy plates behavior subjected to shock loading

  • Muhit, Imrose B.;Sakib, Mostofa N.;Ahmed, Sheikh S.
    • Advances in materials Research
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    • v.6 no.2
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    • pp.155-168
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    • 2017
  • The terrorist attacks and dangers by bomb blast have turned into an emerging issue throughout the world and the protection of the people and structures against terrorist acts depends on the prediction of the response of structures under blast and shock load. In this paper, behavior of aluminum and unidirectionally reinforced E-Glass Epoxy composite plates with and without focal circular holes subjected to shock loading has been identified. For isotropic and orthotropic plates (with and without holes) the classical normal mode approach has been utilized as a part of the processing of theoretical results. To obtain the accurate results, convergence of the results was considered and a number of modes were selected for plate with and without hole individually. Using a shock tube as a loading device, tests have been conducted to composite plates to verify the theoretical results. Moreover, peak dynamic strains, investigated by experiments are also compared with the theoretical values and deviation of the results are discussed accordingly. The strain-time histories are likewise indicated for a specific gauge area for aluminum and composite plates. Comparison of dynamic-amplification factors between the isotropic and the orthotropic plates with and without hole has been discussed.

Fabrication of Piezo-Driven Micropositioning Stage using 3D printer (3D 프린터를 사용한 정밀 스테이지의 제작)

  • Jung, Ho Je;Kim, Jung Hyun
    • Journal of the Korean Society for Precision Engineering
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    • v.31 no.3
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    • pp.277-283
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    • 2014
  • This paper presents the design, optimization and fabrication of a piezo driven micro-positioning stage constructed using a 3D-printer. 3D printing technology provides many advantageous aspects in comparison to traditional manufacturing techniques allowing more rapid prototyping freedom in design, etc. Micro-positioning stages have traditionally been made using metal materials namely aluminum. This paper investigates the possibility of fabricating stages using ABS material with a 3D printer. CAE simulations show that equivalent motion amplification can be achieved compared to a traditional aluminum fabricated stage while the maximum stress is 30 times less. This leads to the possibility of stages with higher magnification factors and less load on the driving piezo element. Experiment results agree with the simulation results. A micro-position stage was fabricated using a 3D printer with ABS material. The motion amplification is very linear and 50 nm stepping was demonstrated.

Seismic performance of RC frame having low strength concrete: Experimental and numerical studies

  • Rizwan, Muhammad;Ahmad, Naveed;Khan, Akhtar Naeem
    • Earthquakes and Structures
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    • v.17 no.1
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    • pp.75-89
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    • 2019
  • The paper presents experimental and numerical studies carried out on low-rise RC frames, typically found in developing countries. Shake table tests were conducted on 1:3 reduced scaled two-story RC frames that included a code conforming SMRF model and another non-compliant model. The later was similar to the code conforming model, except, it was prepared in concrete having strength 33% lower than the design specified, which is commonly found in the region. The models were tested on shake table, through multiple excitations, using acceleration time history of 1994 Northridge earthquake, which was linearly scaled for multi-levels excitations in order to study the structures' damage mechanism and measure the structural response. A representative numerical model was prepared in finite element based program SeismoStruct, simulating the observed local damage mechanisms (bar-slip and joint shear hinging), for seismic analysis of RC frames having weaker beam-column joints. A suite of spectrum compatible acceleration records was obtained from PEER for incremental dynamic analysis of considered RC frames. The seismic performance of considered RC frames was quantified in terms of seismic response parameters (seismic response modification, overstrength and displacement amplification factors), for critical comparison.

Applied 2D equivalent linear program to analyze seismic ground motion: Real case study and parametric investigations

  • Soltani, Navid;Bagheripour, Mohammad Hossein
    • Geomechanics and Engineering
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    • v.30 no.1
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    • pp.1-10
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    • 2022
  • Seismic ground response evaluation is one of the main issues in geotechnical earthquake engineering. These analyses are subsequently divided into one-, two- and three-dimensional methods, and each of which can perform in time or frequency domain. In this study, a novel approach is proposed to assess the seismic site response using two-dimensional transfer functions in frequency domain analysis. Using the proposed formulation, a program is written in MATLAB environment and then promoted utilizing the equivalent linear approach. The accuracy of the written program is evaluated by comparing the obtained results with those of actual recorded data in the Gilroy region during Loma Prieta (1989) and Coyote Lake (1979) earthquakes. In order to precise comparison, acceleration time histories, Fourier amplitude spectra and acceleration response spectra diagrams of calculated and recorded data are presented. The proposed 2D transfer function diagrams are also obtained using mentioned earthquakes which show the amount of amplification or attenuation of the input motion at different frequencies while passing through the soil layer. The results of the proposed method confirm its accuracy and efficiency to evaluate ground motion during earthquakes using two-dimensional model. Then, studies on irregular topographies are carried out, and diagrams of amplification factors are shown.

The Characteristics of Waves on the Steep Sloping Sea Bottom (급경사 해저면에 대한 파랑의 반응특성)

  • Yeom, W.G.;Lee, J.W.
    • Journal of Korean Port Research
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    • v.6 no.2
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    • pp.43-64
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    • 1992
  • This study discusses the interacting with deep water waves approaching from deep water based on the linear wave theory and steep sloping sea bottom floor by the numerical procedure. The results of particular interest are particle velocity and acceleration in x, y, z direction wave height amplification factor reflection coefficient and dimensionless pressure distribution on the steep sloping bottom with respect to the various incident wave angle. The wave loads relative to various bottom slopes, incident wave angles and wave periods on submerged breakwater and pipe are represented in comparison with mild sloping bottom the wave load parameters on the steep sloping bottom seemed to be influenced by variation of incident wave angle. In general the particle velocities and accelerations in x, y, z directions on the steep sloping bottom represented larger value or about two than those on the mild sloping bottom according to incident wave angle. However, the wave height amplification factors did not show distinct difference, but the slight variation with respect to the various incident angle showed on mild sloping bottom. The reflection coefficient increased with respect to increase of the incident angle on the steep sloping bottom the results also indicate that the very steep sloping beach produces a rather substantial amount of reflection as we expected. No significant variation of wave pressure was shown on the steep sloping bottom but it represented a certain amount of variation on the mild sloping bottom according to the various incident wave angle. The analysis at the OTEC site also showed similar results.

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