• Korean Journal of Plant Taxonomy
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• v.42 no.1
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• pp.13-23
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• 2012

The trnL-F region islocated in the large single-copy region of the chloroplast genome. It consists of the trnL gene, the trnL intron, and the trnL-F IGS. Molecular evolution and phylogenetic relationships in Korean Thalictrum L. were investigated using data from the cpDNA trnL-F region. Bayesian and parsimony analyses of the data set with the gap characteristics recovered well-resolved trees that are topologically similar, with clades supported by some indels evolution. Indel events of cpDNA trnL-F in Korean Thalictrum were interpreted as phylogenetically informative characteristics. Sect. Physocarpum (excluding T. osmorhizoides) was an early-diverging group with in the genus and the remaining section formed strongly supported clades. Korean Thalictrum has various evolutionary patterns, such as the spatial distribution of the nucleotide diversity and transversion-type base substitutions in the trnL-F region.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.4
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• pp.27-32
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• 2011

Tin nanoparticles were synthesized at room temperature by a compulsive reduction reaction using tin(II) acetate and tin(II) chloride precursors. When an identical amount (0.015 g) of polyvinyl pyrrolidone (PVP) was added, it was concluded that the probability of abnormally big particles forming increased with an increase in PVP molecular weight, resulting in the wide distribution of Sn nanoparticles. Differential scanning calorimetry measurements were carried out using diethylene glycol solution containing synthesized tin nanoparticles. When the population of specific particles with sizes below 35 nm was adequate, the melting point depression peaks of tin nanoparticles corresponding to the specific size were observed besides an evaporation endothermic peak of DEG during the first heating. Because DEG was evaporated and tin nanoparticles in contact became molten and coarsened during the first heating, a melting peak of bulk tin was only observed at $232^{\circ}C$ during the second heating.

• Journal of Magnetics
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• v.20 no.3
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• pp.308-311
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• 2015

We design a crisscrossed double-layer birdcage (DLBC) coil by modifying the coil geometry of a standard single-layer BC (SLBC) coil to enhance the homogeneity of transmitting magnetic flux density ($B_1{^+}$) along the main magnetic field ($B_0$)-direction for small-animal magnetic resonance imaging (MRI) at 300 MHz. The performance assessment of the crisscrossed DLBC coil is conducted by computational analysis with the finite-difference time domain method (FDTD) and compared with SLBC coil in terms of the $B_1$ and the $B_1{^+}$ distribution. As per the computational calculation studies, the mean value in the two-dimensional $B_1{^+}$ map obtained at the mid-axial slice with the proposed DLBC coil is slightly lower than that obtained with the SLBC coil, but the $B_1{^+}$ value of the DLBC coil in the outermost plane (40 mm away from the central plane) shows improvements of 19.3% and 24.8% over the SLBC coil $B_1{^+}$ value when simulating a spherical phantom and realistic mouse body modeling. These simulation results indicate that, the $B_1{^+}$ homogeneity along the z-direction was improved by using DLBC configuration. Our approach enables $B_1{^+}$ homogeneity improvement along the zdirection, and it can also be applied to ultra-high field (UHF) MRI systems.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.146-146
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• 2017

The pod shattering or dehiscence is essential for the propagation of pod-bearing plant species in the wild, but it causes significant yield losses during harvest of domesticated crop plants. Identifying novel molecular makers, which are linked to seed-shattering genes, is needed to employ the molecular marker-assisted selection for efficiently developing shattering-resistant soybean varieties. In this study, a genetic linkage map was constructed using 115 recombinant inbred lines (RILs) developed from crosses between the pod shattering susceptible variety, Keunol, and resistant variety, Sinpaldal. A 180 K Axiom(R) SoyaSNPs data and pod shattering data from two environments in 2001 and 2015 were used to identify quantitative trait loci (QTL) for pod shattering. A major QTL was identified between two flanking single nucleotide polymorphism (SNP) markers, AX-90320801 and AX-90306327 on chromosome 16 with 1.3 cM interval, 857 kb of physical range. In sequence, genotype distribution analysis was conducted using extreme phenotype RILs. This could narrow down the QTL down to 153 kb on the physical map and was designated as qPDH1-KS with 6 annotated gene models. All exons within qPDH1-KS were sequenced and the 6 polymorphic SNPs affecting the amino acid sequence were identified. To develop universally available molecular markers, 38 Korean soybean cultivars were investigated by the association study using the 6 identified SNPs. Only two SNPswere strongly associated with the pod shattering. These two identified SNPs will help to identify the pod shattering responsible gene and to develop pod shattering-resistant soybean plants using marker-assisted selection.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.203-203
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• 1999

Mass spectrometry technique provides the molecular weight distribution, data on the sequence of repeat units, polymer additives, and impurities, and structural information. time-of-Flight secondary Ion Mass Spectrometry (TOF-SIMS) has been used for structural characterization of various polymers1-2. the masses of repeat units and terminal groups and molecular weight distributions of polymers have been determined from their TOF-SIMS spectra. TOF-SMIS provides good sensitivity and structural specificity for high mass ions so that intact oligomers and large polymer fragments are observed. In this study, we investigated the detailed structural information on the oligomers and fragment ions of branched poly(1,3-butylene adipate) and branched poly[di(ethylene glycol) adipate] and the transesterification products of branched polyesters with trifluoroacetic acid or chloro difluoroacetic acid. Branched polyesters were chosen because they are important polymers but difficult to characterize; thus branched polyesters provide challanging test for TOF-SIMS. TOF-SIMS spectra of polyesters are obtained from thin polymer films cast from solution on a silver substrate. A good solvent for a polumer solution disrupts intermolecular forces between polymer chains but leaves the polumer intact. Transesterification reactions are potentially useful for characterization of high molecular weight and intractable polyesters. Transesterification products of polyesters and trifluoroacetic acid or an integral number of polyester repeat units and an additional diol. The progress of such reactions was monitored using peak intensities of reactants and products in TOF-SIMS spectra. The increasing abundance of tagged ions indicates that the reaction has progressed with time.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.612-619
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• 2012

This study was conducted to investigate the physicochemical properties of the ethanol extracts and soluble dietary fiber from Cassia tora L. seed. The proximate composition of Cassia tora, soluble solid contents, color intensity and contents of emodin and rhein of Cassia tora extract, molecular mass distribution, sugar contents and viscosity of soluble fiber from Cassia tora were analyzed. Cassia tora contains 12.6% of moisture, 5.2% of ash, 13.4% of crude protein, 7.2% of crude fat, 8.8% of insoluble fiber and 48.3% of soluble fiber. The effects of extract condition on soluble solid contents, color intensity and contents of emodin and rhein of Cassia tora extract were investigated. The soluble solid contents were higher in 70% or 50% ethanol extracts than those in 100% ethanol extracts and showed highest value in grind sample extracts. In Hunter's color value, 100% ethanol extracts and whole Cassia tora sample extracts were higher in L and b value, but on the contrary, were lower in a value, than those of the other. The highest emodin and rhein contents were observed in 70% and 50% ethanol extracts, respectively, and showed higher value in room temperature extracts than in heating extracts. The molecular mass of soluble fiber from Cassia tora seed was estimated by gel filtration chromatography. Most soluble fiber(80%) exhibited a molecular mass range of between 50~2000 kDa. The major sugars of soluble fiber from Cassia tora seed were identified as xylose, mannose and galactose. The apparent viscosity of 0.5% soluble fiber from Cassia tora seed was 33 mPas showing a higher value than pectin or xanthan gum.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3541-3546
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• 2014

TEL-AML1 fusion oncogene (t 12; 21) is the most common chromosomal abnormality in childhood acute lymphoblastic leukemia (ALL). This translocation is associated with a good prognosis and rarely shows chemotherapeutic resistance to 3-drug based remission induction phase of treatment as well as overall treatment. Thus, the higher the frequency of this fusion oncogene, the easier to manage childhood ALL in a given region with less intensive chemotherapy. Although global frequency of TEL-AML1 has been reported to be 20-30%, a very low frequency has been found in some geographical regions, including one study from Lahore, Punjab, Pakistan and others from India. The objective of present study was to investigate if this low frequency of TEL-AML1 in pediatric ALL is only in Lahore region or similar situation exists at other representative oncology centers of Pakistan. A total of 167 pediatric ALL patients were recruited from major pediatric oncology centers situated in Lahore, Faisalabad, Peshawar and Islamabad. Patients were tested for TEL-AML1 using nested reverse transcription polymerase chain reaction (RT-PCR). Only 17 out of 167 (10.2%) patients were found to be TEL-AML1 positive. TEL-AML1+ALL patients had favorable prognosis, most of them (82.4%, 14/17) showing early remission and good overall survival. Thus, our findings indicate an overall low frequency of TEL-AML1 in Pakistan pediatric ALL patients, in accordance with lower representation of this prognostically important genetic abnormality in other less developed countries, specifically in south Asia, thus associating it with poor living standards in these ethnic groups. It also indicates ethnic and geographical differences in the distribution of this prognostically important genetic abnormality among childhood ALL patients, which may have a significant bearing on ALL management strategies in different parts of the world.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.119-123
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• 2016

Thyroid cancer, the most common endocrine neoplasia, consists of four main types of carcinomas: papillary, follicular, and anaplastic, all with thyroid follicular origin, and medullary thyroid cancer (MTC) related to para-follicular cells. Cronic diseases such as diverse cancers may be associated with cachexia, especially at advanced stage. Cancer-induced cachexia is associated with diminished quality of life, functional performance, reduced response to antitumor therapy, and increased morbidity and mortality. Myostatin (Mst) is one of the outstanding molecules in the skeletal muscle loss process in cancer and it may be released by both skeletal muscle and cachexia-inducing tumors. Recently changes in serum levels of Mst have been identified as an important factor of cancer-induced cachexia. The goal of this study was to assessserum Mst levels in MTC patients. In this descriptive and case-control study, 90 participants were selected, comprising 45 MTC patients (20 males, $29{\pm}13.9years$, 25 females, $29{\pm}14.5years$) and 45 control individuals (25 males, $23.1{\pm}11.6years$, 20 females, $31.5{\pm}14.4years$). Serum Mst was determined using an ELISA kit and body mass index (BMI) was calculated by weight and height measurements. The Kolmogorov Simonov test showed a normal distribution for log transformed Mst serum levels in both case and control groups. Geometric means were 5.9 and 8.2 ng/ml respectively, and a significant difference was found according to the independent t-test results (P<0.01). There was also a significant difference mean of Mst between females in control and MTC groups, but not for the males. Pearson correlation test showed no correlation between age and BMI with Mst serum levels. The findings of this study support the hypothesis that Mst serum levels may have a potential ability for early diagnosis of cachexia in MTC patients, especially in females.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.311-316
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• 2016

The efficacy of plant breeding has been enhanced by application of molecular markers in population screening and selection. Pepper (Capsicum annuum L.) is a major staple crop that is economically important with worldwide distribution. It is valued for its spicy taste and medicinal effect. The aim of this study was to discover single nucleotide polymorphisms (SNPs), microsatellite markers information, and percentage sharing through orthologous analysis of pepper-specific pungency-related genes. Here, we report the results of transcriptome analysis and microsatellite markers for four pepper varieties that possess a pungency-related gene. Orthologous analyses was performed to identify species-specific pungency-related genes in pepper, Arabidopsis thaliana L., potato (Solanum tuberosum L.), and tomato (Solanum lycopersicum L.). Advancements in next-generation sequencing technologies enabled us to quickly and cost-effectively assemble and characterize genes to select molecular markers in various organisms, including pepper. We identified a total of 9762, 7302, 8596, and 6886 SNPs for the four pepper cultivars Blackcluster, Mandarine, Saengryeg 211, and Saengryeg 213, respectively. We used 454 GS-FLX pyrosequencing to identify microsatellite markers and tri-nucleotide repeats (54.4%), the most common repeats, followed by di-, hexa-, tetra-, and penta-nucleotide repeats. A total of 5156 (15.9%) pepper-specific pungency-related genes were discovered as a result of orthologous analysis.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.123-136
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• 2012

Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tropical and sub-tropical agro-ecosystems worldwide. In recent years, they have also introduced in temperate regions of the world where they have great impact and are posing a serious threat to a variety of greenhouse crops. Begomoviral diseases can in extreme cases reduce yields to zero leading to catastrophic losses in agriculture. They are still evolving and pose a serious threat to sustainable agriculture across the world, particularly in tropics and sub-tropics. Till recently, there have been no records on the occurrence of begomoviral disease in South Korea, however, the etiology of other plant viral diseases are known since last century. The first begomovirus infected sample was collected from sweet potato plant in 2003 and since then there has been gradual increase in the begomoviral epidemics specially in tomato and sweet potato crops. So far, 48 begomovirus sequences originating from various plant species have been submitted in public sequence data base from different parts of the country. The rapid emergence of begomoviral epidemics might be with some of the factors like evolution of new variants of the viruses, appearance of efficient vectors, changing cropping systems, introduction of susceptible plant varieties, increase in global trade in agricultural products, intercontinental transportation networks, and changes in global climatic conditions. Another concern might be the emergence of a begomovirus complex and satellite DNA molecules. Thorough understanding of the pathosystems is needed for the designing of effective managements. Efforts should also be made towards the integration of the resistant genes for the development of transgenic plants specially tomato and sweet potato as they have been found to be widely infected in South Korea. There should be efficient surveillance for emergence or incursions of other begomoviruses and biotypes of whitefly. This review discusses the general characteristics of begomoviruses, transmission by their vector B. tabaci with an especial emphasis on the occurrence and distribution of begomoviruses in South Korea, and control measures that must be addressed in order to develop more sustainable management strategies.