• 한국작물학회지
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• 제59권2호
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• pp.109-127
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• 2014

Maize is one of the most important food and feed crops in the world including Southeast Asia. In spite of numberous efforts with conventional breeding, the maize productions remain low and the loss of yields by drought and downy mildew are still severe in Asia. Genetic improvement of maize has been performed with molecular marker and genetic engineering. Because maize is one of the most widely studied crop for its own genome and has tremendous diversity and variant, maize is considered as a forefront crop in development and estimation of molecular markers for agricultural useful trait in genetics and breeding. Using QTL (Quantitative Trait Loci) and MAS (Marker Assisted Breeding), molecular breeders are able to accelerate the development of drought tolerance or downy mildew resistance maize genotype. The present paper overviews QTL/MAS approaches towards improvement of maize production against drought and downy mildew. We also discuss here the trends and importance of molecular marker and mapping population in maize breeding.

• 아시아태평양코퍼스연구
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• 제1권2호
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• pp.27-39
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• 2020

This paper examines the frequency and distribution of the so-called "non-discourse marker functions" of so in essay writings produced by 200 L1 English speakers and 1,300 EFL learners in China, Japan, Korea, and Taiwan. Based on the data drawn from the International Corpus Network of Asian Learners of English, this study compares EFL learners and L1 English speakers' uses of so, identifying four grammatical uses, as (1) an adverb, (2) part of a fixed phrase, (3) a pro-form, and (4) a conjunction phrase specifying purpose. This study aims to show the wide variability among EFL learners with different L1s, identifying the tendency of usage both common among and specific to the sub-groups of EFL learners. The findings suggest that the learners demonstrate patterns distinctively different from those of L1 English speakers, indicating an underuse of so as a marker expressing "purpose" and an overuse as part of fixed phrases. Compared to L1 English speakers, the learners also tend to overuse so in the discourse marker functions, regardless of their L1s. The study proposes pedagogical implications focusing on discourse flow and diachronic aspects of so in order to understand its multifunctionality, although the latter is primarily suggested for advanced learners.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권2호
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• pp.145-155
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• 2007

Mulberry (Morus spp.) is an economically important tree crop being cultivated in India, China and other sericulturally important countries for its foliage to feed the silk producing insect Bombyx mori L. Genetic improvements of mulberry lag behind to the same in many other economically less important crops due to the complexity of its genetics, the breeding behavior, and the lack of basic information on factors governing important agronomic traits. In this review, the general usage and advantages of different molecular markers including isoenzymes, RFLPs, RAPDs, ISSRs, SSRs, AFLPs and SNPs are described to enlighten their applicability in mulberry genetic improvement programs. Application of DNA markers in germplasm characterization, construction of genetic linkage maps, QTL identification and in marker-assisted selection was also described along with its present status and future prospects.

• 한국유기농업학회지
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• 제26권4호
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• pp.745-757
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• 2018

We analyzed the nuclear ribosomal internal transcribed spacer (ITS) sequence of common buckwheat, Fagopyrum esculentum and tartary buckwheat, F. tataricum. The diversity of the nucleotides and haplotypes, Tajima's D, and Fu's Fs was analyzed and compared among the varieties of common buckwheat and tartary buckwheat. The diversity of nucleotides and haplotypes indicated that the buckwheat populations had undergone rapid population expansion but D and Fs did not support their expansion statistically. The phylogenetic analysis of ITS sequences did not clearly establish the phylogenetic relationships between the varieties of common buckwheat. The In/Del sequence of ITS-1 region could, therefore, be used as a DNA marker to distinguish raw or manufactured products derived from common buckwheat and tartary buckwheat.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2341-2344
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• 2014

Background: p53 protein expression has been detected immunohistochemically in papillary thyroid carcinoma(PTC). We investigated the relations between its expression and clinicopathologic features and its significance as a diagnostic marker. Materials and Methods: We compared and evaluated 93 patients in whom thyroidectomy with lymph node dissection had been performed to treat PTC for clinicopathologic significance and 102 patients with 23 papillary thyroid overt carcinomas (POC), 57 papillary thyroid microcarcinomas(PMC), 5 follicular adenomas (FA), 5 Hashimoto's thyroiditis (HT) and 12 nodular hyperplasias (NH) for significance as a diagnostic marker. Expression of p53 protein was evaluated immunohistochemically in sections of paraffinembedded tissue. Results: Statistical analysis showed significantly different expression of p53 in PTC versus other benign thyroid lesions (BTL).The diagnostic sensitivity and specificity were 85.0% and 72.7%, respectively. Overexpression of p53 protein was observed in 44 of the 93 PTC cases (47.3%), but no significant correlation between p53 protein overexpression and clinicopathologic features (age, size, multiplicity, lymph node metastasis, extrathyroidal extension and vascular invasion) was noted. Conclusions: p53 is valuable to distinguish PTC from other BTL, but there is no correlation between p53 protein overexpression and clinicopathologic features.

• Plant Biotechnology Reports
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• 제2권4호
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• pp.239-243
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• 2008

Simmondsia chinensis (Link) Schneider, a multipurpose and monogeneric dioecious shrub from arid zones, has emerged as a cash crop all over the globe. Its seed propagation poses severe problems due to its male-biased population: the male:female ratio is 5:1. Investigations have been carried out to generate a sex-specific Inter-simple sequence repeat (ISSR) marker for the early detection of male and female plants. Of the 42 primers analysed with a bulk sample of pooled male DNA and a bulk sample of pooled female DNA, only one primer, UBC-807, produced a unique ~1,200 base-pair fragment in the male DNA. To validate this observation, this primer was re-tested with individual male and female samples from eight cultivars. A similar unique ~1,200 bp fragment was present in the male individuals of all eight cultivars and completely absent in the female individuals tested. This is the first report of the use of ISSR markers to ascertain sex in physiologically mature S. chinensis plants.

• 원예과학기술지
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• 제34권6호
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• pp.912-923
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• 2016

Watermelon production is often limited by powdery mildew in areas with a large daily temperature range. Development of resistant watermelon cultivars can protect against powdery mildew; however, little is known about the characteristics of its causal agents. Here, we identified the genus and race of a causal pathogen of powdery mildew in Ansung province of South Korea, and developed molecular markers for the generation of resistant watermelon cultivars. The causal pathogen was determined to be Podosphaera xanthii based on multiple sequence alignments of internal transcribed spacers (ITS) of rDNA. The physiological race was identified as 1W, and the Ansung isolate was named P. xanthii 1W-AN. Following inoculation with the identified P. xanthii 1W-AN, we found inheritance of the resistant gene fitting a single dominant Mendelian model in a segregated population ('SBA' ${\times}$ PI 254744). To develop molecular markers linked to fungus-resistant loci, random amplified polymorphic DNA (RAPD) was accomplished between DNA pooled from eight near-isogenic lines (NILs; $BC_4F_6$), originated from PI 254744 and susceptible 'SBB' watermelon. After sequencing bands from RAPD were identified in all eight NILs and PI254744, 42 sequence-characterized amplifiedregion (SCAR) markers were developed. Overall, 107 $F_2$ plants derived from $BC_4F_6$ NIL-1 ${\times}$ 'SBB' were tested, and one SCAR marker was selected. Sequence comparison between the SCAR marker and the reference watermelon genome identified three Nco I restriction enzyme sites harboring a single nucleotide polymorphism, and codominant cleavage-amplified polymorphic site markers were subsequently developed. A CAPS marker was converted to a high-resolution melt (HRM) marker, which can discriminate C/T SNP (254PMR-HRM3). The 254PMR-HRM3 marker was evaluated in 138 $F_{2:3}$ plants of a segregating population ('SBA' ${\times}$ PI254744) and was presumed to be 4.3 cM from the resistance locus. These results could ensure P. xanthii 1W-AN resistance in watermelon germplasm and aid watermelon cultivar development in marker-assist breeding programs.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권2호
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• pp.79-86
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• 2005

Molecular markers have increasingly been used in plant genetic analysis, due to their obvious advantages over conventional phenotypic markers, as they are highly polymorphic, more in number, stable across different developmental stages, neutral to selection and least influenced by environmental factors. Among the PCR based marker techniques, ISSR is one of the simplest and widely used techniques, which involves amplification of DNA segment present at an amplifiable distance in between two identical microsatellite repeat regions oriented in opposite direction. Though ISSR markers are dominant like RAPD, they are more stable and reproducible. Because of these properties ISSR markers have recently been found using extensively for finger printing, pohylogenetic analysis, population structure analysis, varietal/line identification, genetic mapping, marker-assisted selection, etc. In mulberry (Morus spp.), ISSR markers were used for analyzing phylogenetic relationship among cultivated varieties, between tropical and temperate mulberry, for solving the vexed problem of identifying taxonomic positions of genotypes, for identifying markers associated with leaf yield attributing characters. As ISSR markers are one of the cheapest and easiest marker systems with high efficiency in generating polymorphism among closely related varieties, they would play a major role in mulberry genome analysis in the future.

• 한국정밀공학회지
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• 제32권2호
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• pp.191-198
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• 2015

In this paper, six-degree-of-freedom (DoF). Displacement measurement technique using a compact stereo-vision system is proposed. The measuring system consists of a camera, an optical prism, two plane mirrors, and a planar marker on a target. The target was attached on an object so that its six-DoF displacement can be calculated using a proposed coordinates estimating algorithm and stereo images of the marker. A prototype was designed and fabricated for performance test. From the test results, it can be confirmed that the proposed measuring technique can be applied to monitoring and control of various manipulators.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권1호
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• pp.71-82
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• 2008

Survivin is a member of the inhibitors of apoptosis (IAP) family that have been known to inhibit activated caspases in apoptosis. In contrast to most IAP family members, survivin mRNA is expressed during fetal development, is not found in normal adult tissues and is overexpressed again in the cancer. Though survivin expression has been documented in most human cancers, little is known about its expression in OSCC and its potential value as a predictor of cancer survival. The purpose of this study was to investigate survivin expression in OSCC and to evaluate its value as a prognostic marker. We evaluated survivin expressions in cancer lines and OSCC samples and investigated the relationships between survivin expressions and clini-co-pathological parameters including stage, differentiation, proliferation, lymph node metastasis, blood vessel density, and gelatinolytic activity. With immunohistochemistry, we analyzed survivin expression in 38 OSCCs. Patients' clinico-pathological parameters and their survival rate were analyzed to reveal their correlations with Survivin expressions. We cultured oral cancer cell lines and evaluated the correlation between gelatinolytic activities and survivin expressions of them. Survivin protein was observed both in nuclei and cytoplasm of tumor specimens while little or not observed in normal gingival mucosal tissues. Additionally, survivin expressions were correlated with lymph node metastasis, tumor proliferation and survival rate. Survivin expression was observed in 100% of 38 samples of OSCC and its expression levels are statistically associated with the proliferative activity of the tumors, lymph node metastasis and the survival of the patients. Based on these results, survivin is commonly expressed in OSCC and may thus provide valuable prognostic information related with lymph node metastasis, proliferation and survival rate as well as a potential therapeutic target in OSCC.