• 제목/요약/키워드: Quantification Method

검색결과 1,493건 처리시간 0.037초

Candela 개념의 광량정량화 활용에 관한 연구 (The quantification of photon counts using the concept of candela)

  • 김현식;최은서;이병일
    • 통합자연과학논문집
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    • 제1권1호
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    • pp.1-4
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    • 2008
  • We developed quantification method based on the concept of candela in physics. The measurement of fluorescence signal from a nude mouse in the research of molecular biology. In the measurement of the optical signal with CCD, the quantification method for photon counts based on bio-luminescence imaging technique can provide comparative reference data. In this paper, we described theoretical derivation of our proposed concept. We hope this method could be a useful standard reference for quantitative date analysis in optical imaging.

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Skin biopsy: an emerging method for small nerve fiber evaluation

  • Sohn, Eun Hee
    • Annals of Clinical Neurophysiology
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    • 제20권1호
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    • pp.3-11
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    • 2018
  • Skin biopsy and staining the specimens with immuno-reactive markers has been proven to be a useful method to demonstrate the pathologic status of small nerve fibers. Quantification of intraepidermal nerve fiber density using anti-protein gene product 9.5 antibody is a standard method to diagnose small fiber neuropathy. Skin biopsy also makes it possible to differentiate the nerve fibers according to their function by using different markers. Quantification of dermal structures with different types of nerve fibers could reveal the pathophysiologic mechanism of the disease state.

Development and validation of an analytical method for the quantification of 2,6-diisopropylnaphthalene in agricultural products using GC-MS/MS

  • Lee, Han Sol;Park, Ji-Su;Lee, Su Jung;Shin, Hye-Sun;Chung, Yun mi;Choi, Ha na;Yun, Sang Soon;Jung, Yong-hyun;Oh, Jae-Ho
    • 분석과학
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    • 제34권1호
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    • pp.1-8
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    • 2021
  • An analytical method was developed and optimized for the quantification of a plant growth regulator, 2,6-diisopropylnaphthalene (2,6-DIPN), in agricultural products using gas chromatography-tandem mass spectrometry. The samples were extracted, partitioned, and were purified using a Florisil® cartridge. To validate the analytical method, its specificity, linearity, limit of detection (LOD) and limit of quantification (LOQ) of the instrument, LOQ of the analytical method (MLOQ), accuracy, and repeatability were considered. The method displayed excellent results during validation, and is suitable for the determination and quantification of the low residual levels of the analyte in the agricultural samples. All of the results with the optimized method were satisfactory and within the criteria ranges requested in the Codex Alimentarius Commission guidelines and the Ministry of Food and Drug Safety guidelines for pesticide residue analysis. The developed method is simple and accurate and can be used as a basis for safety management of 2,6-DIPN.

Development of a real-time PCR method for detection and quantification of the parasitic protozoan Perkinsus olseni

  • Gajamange, Dinesh;Yoon, Jong-Man;Park, Kyung-Il
    • 한국패류학회지
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    • 제27권4호
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    • pp.387-393
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    • 2011
  • The objective of this study was to develop a real-time PCR method for the rapid detection and quantification of the protozoan pathogen Perkinsus olseni using a TaqMan probe. For the standard, genomic DNA was extracted from $10^5$ in vitro-cultured P. olseni trophozoites, and then 10-fold serial dilutions to the level of a single cell were prepared. To test the reliability of the technique, triplicates of genomic DNA were extracted from $5{\times}10^4$ cells and 10-fold serial dilutions to the level of 5 cells were prepared. The standards and samples were analyzed in duplicate using an $Exicycler^{TM}$ 96 real-time quantitative thermal block. For quantification, the threshold cycle ($C_T$) values of samples were compared with those obtained from standard dilutions. There was a strong linear relationship between the $C_T$ value and the log concentration of cells in the standard ($r^2$ = 0.996). Detection of DNA at a concentration as low as the equivalent of a single cell showed that the assay was sensitive enough to detect a single cell of P. olseni. The estimated number of P. olseni cells was similar to the original cell concentrations, indicating the reliability of P. olseni quantification by real-time PCR. Accordingly, the designed primers and probe may be used for the rapid detection and quantification of P. olseni from clam tissue, environmental water, and sediment samples.

Right Ventricular Mass Quantification Using Cardiac CT and a Semiautomatic Three-Dimensional Hybrid Segmentation Approach: A Pilot Study

  • Hyun Woo Goo
    • Korean Journal of Radiology
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    • 제22권6호
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    • pp.901-911
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    • 2021
  • Objective: To evaluate the technical applicability of a semiautomatic three-dimensional (3D) hybrid CT segmentation method for the quantification of right ventricular mass in patients with cardiovascular disease. Materials and Methods: Cardiac CT (270 cardiac phases) was used to quantify right ventricular mass using a semiautomatic 3D hybrid segmentation method in 195 patients with cardiovascular disease. Data from 270 cardiac phases were divided into subgroups based on the extent of the segmentation error (no error; ≤ 10% error; > 10% error [technical failure]), defined as discontinuous areas in the right ventricular myocardium. The reproducibility of the right ventricular mass quantification was assessed. In patients with no error or < 10% error, the right ventricular mass was compared and correlated between paired end-systolic and end-diastolic data. The error rate and right ventricular mass were compared based on right ventricular hypertrophy groups. Results: The quantification of right ventricular mass was technically applicable in 96.3% (260/270) of CT data, with no error in 54.4% (147/270) and ≤ 10% error in 41.9% (113/270) of cases. Technical failure was observed in 3.7% (10/270) of cases. The reproducibility of the quantification was high (intraclass correlation coefficient = 0.999, p < 0.001). The indexed mass was significantly greater at end-systole than at end-diastole (45.9 ± 22.1 g/m2 vs. 39.7 ± 20.2 g/m2, p < 0.001), and paired values were highly correlated (r = 0.96, p < 0.001). Fewer errors were observed in severe right ventricular hypertrophy and at the end-systolic phase. The indexed right ventricular mass was significantly higher in severe right ventricular hypertrophy (p < 0.02), except in the comparison of the end-diastolic data between no hypertrophy and mild hypertrophy groups (p > 0.1). Conclusion: CT quantification of right ventricular mass using a semiautomatic 3D hybrid segmentation is technically applicable with high reproducibility in most patients with cardiovascular disease.

Selective Extraction and Quantification of Glutathione using Maleimide-Presenting Gold Nanoparticles

  • Oh, Hongseok;Lee, Jeongwook;Yeo, Woon-Seok
    • Bulletin of the Korean Chemical Society
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    • 제35권10호
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    • pp.3047-3051
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    • 2014
  • In this paper, we describe a new method for the selective extraction and quantification of glutathione (GSH) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and maleimide-presenting gold nanoparticles (Mal-AuNPs). Our strategy utilizes the Michael addition to selectively extract GSH, from chosen samples, onto the maleimide of Mal-AuNPs. After the extraction step, the GSH bound to the AuNPs was analyzed by MALDI-TOF MS in the presence of an internal standard which was prepared by reacting Mal-AuNPs with isotope-labeled GSH ($GSH^*$). The $GSH^*$ has the same structure as GSH but a higher molecular weight, and therefore, enables absolute quantification of GSH by comparing the mass signal intensities of the GSH- and $GSH^*$-conjugated alkanethiols. Our strategy was verified by analyzing GSH-spiked fetal bovine serum and NIH 3T3 cells.

생리음향을 이용한 도어 닫힘음의 정량적 평가를 위한 새로운 음질요소의 개발 (Sound Metric Design for Quantification of Door Closing Sound Utilizing Physiological Acoustics)

  • 신태진;이승민;이상권
    • 한국소음진동공학회논문집
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    • 제23권1호
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    • pp.73-83
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    • 2013
  • In previous works, psychoacoustic parameters have been used for objective quantification. However, these parameters do not agree well with subjective assessment. Therefore, the correlation between psychoacoustic parameters and the subjective rating of door closing sounds of sampled cars is low, and it is not sufficient to use psychoacoustic parameters as an objective metric to quantify the sound quality of door closing sounds. In this paper, a new method is proposed to objectively quantify the sound quality based on physiological acoustics and statistical signal processing. The gammatone filter, as a pre-processing, is used in models of the auditory system and kurtosis, which is the fourth-order moment of temporal signal, and is used to extract information about sound quality quantification for door closing sounds. The new metric obtained through the proposed method is highly correlated with subjective rating, and it is successfully applied to the quantification of the sound quality of door closing sounds.

Epifluorescence Microscopy with Image Analysis as a Promising Method for Multispecies Biofilm Quantification

  • Ji Won Lee;So-Yeon Jeong;Tae Gwan Kim
    • Journal of Microbiology and Biotechnology
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    • 제33권3호
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    • pp.348-355
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    • 2023
  • Epifluorescence microscopy with image analysis was evaluated as a biofilm quantification method (i.e., quantification of surface area colonized by biofilms), in comparison with crystal violet (CV) staining. We performed different experiments to generate multispecies biofilms with natural and artificial bacterial assemblages. First, four species were inoculated daily in 16 different sequences to form biofilms (surface colonization, 0.1%-56.6%). Second, a 9-species assemblage was allowed to form biofilms under 10 acylase treatment episodes (33.8%-55.6%). The two methods comparably measured the quantitative variation in biofilms, exhibiting a strong positive relationship (R2 ≥ 0.7). Moreover, the two methods exhibited similar levels of variation coefficients. Finally, six synthetic and two natural consortia were allowed to form biofilms for 14 days, and their temporal dynamics were monitored. The two methods were comparable in quantifying four biofilms colonizing ≥18.7% (R2 ≥ 0.64), but not for the other biofilms colonizing ≤ 3.7% (R2 ≤ 0.25). In addition, the two methods exhibited comparable coefficients of variation in the four biofilms. Microscopy and CV staining comparably measured the quantitative variation of biofilms, exhibiting a strongly positive relationship, although microscopy cannot appropriately quantify the biofilms below the threshold colonization. Microscopy with image analysis is a promising approach for easily and rapidly estimating absolute quantity of multispecies biofilms.

The effect of the number of subintervals upon the quantification of the seismic probabilistic safety assessment of a nuclear power plant

  • Ji Suk Kim;Man Cheol Kim
    • Nuclear Engineering and Technology
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    • 제55권4호
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    • pp.1420-1427
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    • 2023
  • Seismic risk has received increased attention since the 2011 Fukushima accident in Japan. The seismic risk of a nuclear power plant is evaluated via seismic probabilistic safety assessment (PSA), for which several methods are available. Recently, the discrete approach has become widely used. This approximates the seismic risk by discretizing the ground motion level interval into a small number of subintervals with the expectation of providing a conservative result. The present study examines the effect of the number of subintervals upon the results of seismic risk quantification. It is demonstrated that a small number of subintervals may lead to either an underestimation or overestimation of the seismic risk depending on the ground motion level. The present paper also provides a method for finding the boundaries between overestimation and underestimation regions, and illustrates the effect of the number of subintervals upon the seismic risk evaluation with an example. By providing a method for determining the effect of a small number of subintervals upon the results of seismic risk quantification, the present study will assist seismic PSA analysts to determine the appropriate number of subintervals and to better understand seismic risk quantification.

Development of an uncertainty quantification approach with reduced computational cost for seismic fragility assessment of cable-stayed bridges

  • Akhoondzade-Noghabi, Vahid;Bargi, Khosrow
    • Earthquakes and Structures
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    • 제23권4호
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    • pp.385-401
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    • 2022
  • Uncertainty quantification is the most important challenge in seismic fragility assessment of structures. The precision increment of the quantification method leads to reliable results but at the same time increases the computational costs and the latter will be so undesirable in cases such as reliability-based design optimization which includes numerous probabilistic seismic analyses. Accordingly, the authors' effort has been put on the development and validation of an approach that has reduced computational cost in seismic fragility assessment. In this regard, it is necessary to apply the appropriate methods for consideration of two categories of uncertainties consisting of uncertainties related to the ground motions and structural characteristics, separately. Also, cable-stayed bridges have been specifically selected because as a result of their complexity and the according time-consuming seismic analyses, reducing the computations corresponding to their fragility analyses is worthy of studying. To achieve this, the fragility assessment of three case studies is performed based on existing and proposed approaches, and a comparative study on the efficiency in the estimation of seismic responses. For this purpose, statistical validation is conducted on the seismic demand and fragility resulting from the mentioned approaches, and through a comprehensive interpretation, sufficient arguments for the acceptable errors of the proposed approach are presented. Finally, this study concludes that the combination of the Capacity Spectrum Method (CSM) and Uniform Design Sampling (UDS) in advanced proposed forms can provide adequate accuracy in seismic fragility estimation at a significantly reduced computational cost.