• Nuclear Engineering and Technology
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• 제50권7호
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• pp.1006-1016
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• 2018

Since the early forties, researchers from around the world have been studying the phenomenon of deadtime in radiation detectors. Many have attempted to develop models to represent this phenomenon. Two highly idealized models; paralyzable and non-paralyzable are commonly used by most individuals involved in radiation measurements. Most put little thought about the operating conditions and applicability of these ideal models for their experimental conditions. So far, there is no general agreement on the applicability of any given model for a specific detector under specific operating conditions, let alone a universal model for all detectors and all operating conditions. Further the related problem of pile-up is often confused with the deadtime phenomenon. Much work, is needed to devise a generalized and practical solution to these related problems. Many methods have been developed to measure and compensate for the detector deadtime count loss, and many researchers have addressed deadtime and pulse pile-up. The goal of this article is to summarize the state of science of deadtime; measurement and compensation techniques as proposed by some of the most significant work on these topics and to review the deadtime correction models applicable to present day radiation detection systems.

• 비교문화연구
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• 제53권
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• pp.163-192
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• 2018

이 논문은 형태통사적 특성이 유사한 한국어와 일본어의 다국어 범용 의존관계 주석체계(Universal Dependencies, 이하 UD) 적용 사례를 살펴보고 비교 분석을 통해서 한국어의 UD 적용 및 개선 방안을 고찰하는 것을 목적으로 한다. 한국어와 일본어는 교착어적 특성으로 인하여 어미와 조사가 매우 발달되어 있다. 그러므로 영어와 같은 굴절어를 중심으로 설계된 UD를 적용하는 데에 많은 어려움이 있다. 이에 본고에서는 UD를 구성하는 범용 품사 주석(Universal POS, 이하 UPOS)과 범용 의존관계 주석(Universal Dependency Relations, 이하 DEPREL)의 적용과 그에 따른 논의들을 검토하였다. UPOS의 경우 AUX(조동사 표지), ADJ(형용사 표지), VERB(동사 표지)처럼 서술어와 관련된 주석 표지의 처리와 조사, 어미와 같은 기능어의 처리 방안을 살펴보았으며 접속사 및 이와 관련된 단위를 어떻게 처리하고 있는지 검토하였다. DEPREL과 관련해서는, 구문 표지를 주석하는 기본 단위의 문제에서 출발하여 통사적 문제를 어떻게 반영하고 있는지 살펴보았다. 지배소 설정 방식과 병렬 구조의 주석 방식, case(격 관계 표지)와 aux(조동사 관계 표지) 주석 방식을 검토하였다. 다양한 관계 주석 표지 중에서 특히 case와 aux에 집중하여 논의한 것은 한국어와의 주석 표지 적용 양상을 비교했을 때 분포 상 가장 두드러지는 차이를 나타내기 때문이다. case는 한국어와 일본어 모두 조사와 관련이 있고, aux는 한국어에서는 보조용언, 일본어에서는 조동사와 관련이 있는 표지이다. 구체적인 주석 양상을 살펴본 결과 일본어의 aux는 서법 조동사뿐만 아니라 동사에 문법적 의미를 더하는 요소, 한국어의 어미에 해당하는 형태에도 aux를 할당하기 때문에 주석이 차지하는 비율이 크게 차이가 나는 것으로 밝혀졌다. iobj(간접목적어 관계 표지)와 관련해서는 일본어에서 간접목적어를 인정하는 데에 반해 한국어에서는 간접목적어를 인정하지 않는 경우가 더 많았다. 일본어의 UD 주석에서 형태 분석 기본 단위인 '단단위'를 기본 구문 주석 단위로 하되 '장단위'와 문절 정보를 이용하는 것처럼, 한국어에서도 형태 분석 단위를 의존관계 주석의 정보로 활용하는 방안에 대해서 고려할 필요가 있다.

• The Plant Pathology Journal
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• 제24권1호
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• pp.17-23
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• 2008

A total of 33 isolates of Colletotrichum species obtained from pepper, apple, and strawberry in 2001 and 2002 were identified based on mycological characteristics, responses to fungicides carbendazim and the mixture of carbendazim and diethofencarb, and nucleotide sequence analysis of internal transcribed spacer (ITS) regionMost of the Colletotrichum isolates from pepper could be identified as C. acutatum. The pepper isolates produced grey white mycelia that gradually changed to dark gray. The conidia were variable in size, and almost cylindrical in shape with at least one rounded end. They could grow on PDA amended with carbendazim or with the mixture of carbendazim and diethofencarb at $10{\mu}g/ml$, to which the isolates from apple and strawberry were very sensitive. A part of the ITS regions from the Colletotrichum isolates was amplified with the specific primers designed for C. acutatum (Ca1-1) or C. gloeosporioides (Cg1-3). A primer pair of Ca1-1 and a universal primer (ITS4) amplified a 496-bp DNA fragment from all of the pepper isolates examined and one apple isolate. Taken together, it is conclusive that the Colletotrichum isolates causing the typical lesion of anthracnose on pepper fruits are C. acutatum.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.205-211
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• 2006

A quantitative analytical method to detect new lines of genetically modified (GM) maize, NK603 and TC1507, has been developed by using a real-time polymerase chain reaction (PCR). To detect these GM lines, two specific primer pairs and probes were designed. A plasmid as a reference molecule was constructed from an endogenous DNA sequence of maize, a universal sequence of a cauliflower mosaic virus (CaMV) 35S promoter used in most GMOs, and each DNA sequence specific to the NK603 and TC1507 lines. For the validation of this method, the test samples of 0, 0.1, 0.5, 1.0, 3.0, 5.0, and 10.0% each of the NK603 and TC1507 GM maize were quantitated. At the 3.0% level, the biases (mean vs. true value) for the NK603 and TC1507 lines were 3.3% and 15.7%, respectively, and their relative standard deviations were 7.2% and 5.5%, respectively. These results indicate that the PCR method developed in this study can be used to quantitatively detect the NK603 and TC1507 lines of GM maize.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.120.2-120
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• 2003

Agrobacterium vitis is a causal agent of crown-gall disease on grapevine. In Korea, grapevine variety (GeoBong) have severely been infected by the bacteria since stems of the variety were buried in soil for overwintering. Infection ratio over 70-80％ was observed on 7 years old GeoBong grapevine in Ansung and Cheonan. PCR specific primers for A. vitis strains were designed using nucleotide sequences of vir A gene in Ti-Plasmid, pheA gene in chromosomal DNA and a URP-PCR polymorphic band. Three hundred bacterial strains were isolated from the different 80 galls formed on GeoBong grapevine in Cheonan and Ansung of Korea and were screened to identify A. vitis using the three specific PCR primers for Agrobacterium vitis. Twenty-four bacterial strains that are detected by the primers were further confirmed by pathogenicity and biochemical methods. To investigate the genomic diversity of the bacterial strains, twenty primers of 20 mer referred to universal rice primers (URP) were applied for PCR fingerprinting, Of them, URP2R and URP2F primers could effectively be used to detect polymorphism within the bacterial strains.

• Restorative Dentistry and Endodontics
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• 제40권1호
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• pp.23-29
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• 2015

Objectives: The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods: Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/Silorane and Silorane groups). Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE) were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray), with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups), or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE) (Three-step/Methacrylate group) (n = 6). The restored teeth were sectioned into stick-shaped test specimens ($1.0{\times}1.0mm$), and coupled to a universal test machine (0.5 mm/min) to perform microtensile testing. Results: Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p < 0.05). However, it was not significantly different from Pre-etching/Silorane and Methacrylate groups. Conclusions: Pre-etching increased bond strength of silorane-based composite specific adhesive system to dentin.

• KSBB Journal
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• 제29권5호
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• pp.361-371
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• 2014

Mycoplasma is well recognized as one of the most prevalent and serious microbial contaminants of biologic manufacturing processes. Conventional methods for mycoplasma testing, direct culture method and indirect indicator cell culture method, are lengthy, costly and less sensitive to noncultivable species. In this report, we describe a new TaqMan probe-based real-time PCR method for rapid and quantitative detection of mycoplasma contamination during manufacture of biologics. Universal mycoplasma primers were used for mycoplasma PCR and mycoplasma DNA was quantified by use of a specific TaqMan probe. Specificity, sensitivity, and robustness of the real-time PCR method was validated according to the European Pharmacopoeia. The validation results met required criteria to justify its use as a replacement for the culture method. The established real-time PCR assay was successfully applied to the detection of mycoplasma from human keratinocyte and mesenchymal stem cell as well as Vero cell lines artificially infected with mycoplasma. The overall results indicated that this rapid, specific, sensitive, and robust assay can be reliably used for quantitative detection of mycoplasma contamination during manufacture of biologics.

• Journal of Microbiology
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• 제41권4호
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• pp.327-334
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• 2003

This study employed two PCR-based 16S rDNA approaches, amplified rDNA restriction analysis (ARDRA) and denaturing gradient gel electrophoresis (DGGE), to characterize the bacterial community structure in groundwater. Samples were collected from groundwater for the use by private residences, as well as for industrial and agricultural purposes, in Ansan City. Each PCR product was obtained by PCR with eubacteria 16S rDNA and variable V3 region specific primer sets. After amplification, the 16S rDNA PCR products were digested with 4-base site specific restriction endonucleases, and the restriction pattern analyzed. The genetic diversity and similarity of the groundwater bacterial community was analyzed by eubacteria universal primer sets for the amplification of variable V3 regions of the bacterial 16S rDNA. The result of the bacterial community analysis, by ARDRA and DGGE, revealed the same pattern. The highest diversity was found in groundwater from site G1, which was used in residences. In the DGGE profile, a high intensity band was sequenced, and revealed to be Pseudomonas sp. strain P51.

• Genomics & Informatics
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• 제20권4호
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• pp.46.1-46.7
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• 2022

Influenza A virus (IAV) is the most widespread pathogen causing human respiratory infections. Although polymerase chain reaction (PCR)-based methods are currently the most commonly used tools for IAV detection, PCR is not ideal for point-of-care testing. In this study, we aimed to develop a more rapid and sensitive method than PCR-based tools to detect IAV using loop-mediated isothermal amplification (LAMP) technology. We designed reverse-transcriptional (RT)-LAMP primers targeting the hemagglutinin gene. RNAs from reference H1N1 and H3N2 showed specific RT-LAMP signals with the designed primers. We optimized the reaction conditions and developed universal reaction conditions for both LAMP assays. Under these conditions, the detection limit was 50 copies for both RT-LAMP assays. There was no non-specific signal to 19 non-IAV respiratory viruses, such as influenza B virus, coronaviruses, and respiratory syncytial viruses. Regarding the reaction time, a positive signal was detected within 25 min after starting the reaction. In conclusion, our RT-LAMP assay has high sensitivity and specificity for the detection of the H1 and H3 subtypes, making it suitable for point-of-care IAV testing.

• 음성과학
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• 제11권3호
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• pp.7-21
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• 2004

The present study aims to investigate domain-initial strengthening phenomenon, which refers to strengthening of articulatory gestures at the initial positions of prosodic domains. More specifically, this paper presents the result of an experimental study of initial syllables with onset consonants (initial-syllable vowels henceforth) of various prosodic domains in English and Hamkyeong Korean, a pitch accent dialect spoken in the northern part of North Korea. The durations of initial-syllable vowels are compared to those of second vowels in real-word tokens for both languages, controlling both stress and segmental environment. Hamkyeong Korean, like English, tuned out to strengthen the domain-initial consonants. With regard to vowel durations, no significant prosodic effect was found in English. On the other hand, Hamkyeong Korean showed significant differences between the durations of initial and non-initial vowels in the higher prosodic domains. The theoretical implications of the findings are as follows: The potentially universal phenomenon of initial strengthening is shown to be subject to language specific variations in its implementation. More importantly, the distinct phonetics- phonology model (Pierrehumbert & Beckman, 1998; Keating, 1990; Cohn, 1993) is better equipped to account for the facts in the present study.