• 대한기계학회논문집A
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• 제27권10호
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• pp.1754-1761
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• 2003

The atomic force microscopy (AFM) based lithographic technique has been used directly to machine material surface and fabricate nano components in MEMS (micro electro mechanical system). In this paper, three-dimensional molecular dynamics (MD) simulations have been conducted to evaluate the characteristic of deformation process at atomistic scale for nano-lithography process. Effects of specific combinations of crystal orientations and cutting directions on the nature of atomistic deformation were investigated. The interatomic force between diamond tool and workpiece of copper material was assumed to be derived from the Morse potential function. The variation of tool geometry and cutting depth was also evaluated and the effect on machinability was investigated. The result of the simulation shows that crystal plane and cutting direction significantly influenced the variation of the cutting forces and the nature of deformation ahead of the tool as well as the surface deformation of the machined surface.

• 한국인쇄학회지
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• 제29권1호
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• pp.45-59
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• 2011

According as gradually increasing the demand for Eco-friendly products it has been progressed fairly development at a field of printing and printing inks. The Inks are used by soy oil beginning of ink industry for preventing environment. Now it is possible to make Eco-friendly inks with vegetable ester. So it is not necessary to use petroleum-based solvents for preventing environment. But There is some problems if using vegetable ester to inks. Vegetable ester has high solubility, it causes misting and low viscosity of the Inks. So resin is required high performance. Thus, in this paper, I studied about the properties variation of the Varnish and inks According to using the phenolic modified rosin ester and Soy oil Methyl esters. The compared in order of average molecular weight by the GPC method, rheological properties were found by rotational rheometer, and emulsion behavior were compared by high speed emulsification tester.

• Parasites, Hosts and Diseases
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• 제42권4호
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• pp.159-167
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• 2004

Sequences of the complete protein-coding portions of the mitochondrial (mt) genome were analysed for 6 species of cestodes (including hydatid tapeworms and the pork tapeworm) and 5 species of trematodes (blood flukes and liver- and lung-flukes). A near-complete sequence was also available for an additional trematode (the blood fluke Schistosoma malayensis). All of these parasites belong to a large flatworm taxon named the Neodermata. Considerable variation was found in the base composition of the protein-coding genes among these neodermatans. This variation was reflected in statistically-significant differences in numbers of each inferred amino acid between many pairs of species. Both convergence and divergence in nucleotide, and hence amino acid, composition was noted among groups within the Neodermata. Considerable variation in skew (unequal representation of complementary bases on the same strand) was found among the species studied. A pattern is thus emerging of diversity in the mt genome in neodermatans that may cast light on evolution of mt genomes generally.

• 생명과학회지
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• 제19권10호
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• pp.1382-1388
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• 2009

Rubus crataegifolius is a shrub species and is primarily distributed throughout Asia and Europe. We collected 550 representative samples of the eleven populations in Korea to estimate leaf variation within species. The 35 morphological characteristics allowed us to resolve well-supported fixed characteristics and variable characteristics. Sixteen of twenty-three quantitative characteristics and five of twelve qualitative characteristics showed significant differences among populations. We argued that the population differentiation can accounted for the variation in phenetic characteristics such as spine in this species, but were less successful in accounting for variation in other traits. Within a polystatistic leaf structure, their morphological differences could be modulated by ecological pressure such as temperature, altitude, duration of sunshine, and solar radiation. The phenogram showed two distinct clades. One was a group in central Korea and the other was a group in the southern regions of Korea. If morphological characteristics in R. crataegifolius populations reflect their ecological niche, morphology should be regarded with caution as the main criterion for population studies in R. crataegifolius.

• 한국약용작물학회지
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• 제13권2호
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• pp.69-74
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• 2005

Kalopanax pictus is a long-lived woody species mostly distributed in East Asia. K. pictus has been regarded as medically and ecologically important species in Korea. Thornless castor aralia variant, local name 'Cheongsong' is an endemic to Cheongsong province in Korea. Random amplified polymorphic DNA (RAPD) was used to investigate the genetic variation and structure of Korean populations of two species. A high level of genetic variation was found in six K. pictus populations. Twelve primers revealed 49 loci, of which 29 were polymorphic (59.2%). Nei's gene diversity for K.pictus and K. pictus variant were 0.119 and 0.098, respectively. Mean of genetic diversity in K. pictus was higher than average values for species with similar life history traits. The asexual and sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. An indirect estimate of the number of migrants per generation (Nm=0.857) indicated that gene flow was not extensive among Korean populations of K.pictus. It is suggested that the isolation of geographical distance and reproductive isolation between K.pictus and K.pictus variant populations may have played roles in shaping the population structure of this species.

• Journal of Plant Biotechnology
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• 제47권4호
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• pp.273-282
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• 2020

In Vietnam, Celastrus hindsii Benth, a medicinal plant rich in secondary metabolites, has been used to alleviate distress caused by ulcers, tumors, and inflammation for generations. The occurrence of two phenotypes, Broad Leaf (BL) and Narrow Leaf (NL), has raised questions about the selection of appropriate varieties for conservation and crop improvement to enhance medicinal properties. This study examined molecular differences in C. hindsii by comparing protein profiles between the NL and BL types using 2D-PAGE and MS. Peptide sequences and proteins were identified by matching MS data against the MSPnr100 databases and verified using the MultiIdent tool on ExPASy and the Blast2GO software. Our results revealed notable variations in protein abundance between the NL and BL proteomes. Selected proteins were confidently identified from 12 protein spots, thereby highlighting the molecular variation between NL and BL proteomes. Upregulated proteins in BL were found to be associated with flavonoid and amino acid biosynthesis as well as nuclease metabolism, which probably attributed to the intraspecific variations. Several bioactive proteins identified in this study can have applications in cancer therapeutics. Therefore, the BL phenotype characterized by healthier external morphological features has higher levels of bioactive compounds and could be better suited for medicinal use.

• Asian-Australasian Journal of Animal Sciences
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• 제17권4호
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• pp.441-444
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• 2004

The genetic diversities and relationships of 10 Chinese indigenous pig breeds and three exotic pig breeds have been evaluated using 26 microsatellites recommended by the Food and Agriculture Organization & the International Society of Animal Genetics (FAO-ISAG). The allele frequencies, genetic heterozygosity (H) and polymorphism information content (PIC) have been calculated. The results showed that genetic diversity of Chinese indigenous pig breeds is higher than that of the introduced pig breeds. The clustering of 10 breeds is generally consistent with their geographical distribution.

• Journal of Plant Biotechnology
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• 제46권2호
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• pp.61-70
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• 2019

There is vast genetic diversity of Myanmar Mangoes. This study mainly focused on indigenous thirteen different mango landraces cultivated in central area of Myanmar, Kyauk-se District and their fruit characteristics by 18 descriptors together with genetic relationship among them by 12 SSR markers. Based on the morpho-physical characters, a wide variation among accessions was found. Genetic characterization of thirteen mango genotypes resulted in the detection of 302 scorable polymorphic bands with an average of 4.33 alleles per locus and an average polymorphism information content (PIC) of 0.7. All the genotypes were grouped into two major clusters by UPGMA cluster analysis and a genetic similarity was observed in a range of 61 ~ 85%. This study may somehow contribute insights into the identification of regional mango diversity in Myanmar and would be useful for future mango breeding program.

• Journal of Forest and Environmental Science
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• 제29권3호
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• pp.200-210
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• 2013

Biochemical characteristics of 24 Pongamia pinnata genotypes (candidate plus trees) from three agroclimatic zones were estimated and molecular characterization through RAPD markers was done. Various biochemical characters viz. seed oil, total carbohydrates, protein, acid value and Iodine number recorded significant variation among different genotypes. The highest seed oil content was 41.87% while seeds of 14 genotypes recorded above average (32.11%) for the trait. Seed oil and protein content exhibited a significant positive correlation and moderate heritability. Out of the initially selected twenty-five random primers, twenty-two RAPD primers were found to be highly reproducible and produced a total of 183 loci of which 147 (80.32%) loci were polymorphic. Percentage of polymorphism varied from 44% to 100% with an average of 80.62%. High level of genetic variation was found among different genotypes of P. pinnata. Both molecular and oil content (biochemical) markers appeared useful in analyzing the extent of genetic diversity in Pongamia and the result of these analyses will help to better understand the genetic diversity and relationship among populations. Overall, the Pongamia genotypes included in the study showed a correlation with their geographical origins such that genotypes from the same region tend to have higher genetic similarity as compared to those from different regions. However, in UPGMA based Nei's analysis, some genotypes were found not to be grouped based on geographical origins possibly due to the exchange of germplasm over time between farmers across the regions. The results from oil content analyses showed that several genotypes in 'Central and Western Plateau' agroclimatic zone of Jharkhand displayed a good potential for high oil content. The study provides insight about P. pinnata populations in Jharkhand (India) and constitutes a set of useful background information that can be used as a basis for future breeding strategy and improvement of the species.

• Molecules and Cells
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• 제27권4호
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• pp.459-465
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• 2009

MUG1 is a MULE transposon-related domesticated gene in plants. We assessed the sequence diversity, neutrality, expression, and phylogenetics of the MUG1 gene among Oryza ssp. We found MUG1 expression in all tissues analyzed, with different levels in O. sativa. There were 408 variation sites in the 3886 bp of MUG1 locus. The nucleotide diversity of the MUG1 was higher than functionally known genes in rice. The nucleotide diversity (${\pi}$) in the domains was lower than the average nucleotide diversity in whole coding region. The ${\pi}$ values in nonsynonymous sites were lower than those of synonymous sites. Tajima D and Fu and Li $D^*$ values were mostly negative values, suggesting purifying selection in MUG1 sequences of Oryza ssp. Genome-specific variation and phylogenetic analyses show a general grouping of MUG1 sequences congruent with Oryza ssp. biogeography; however, our MUG1 phylogenetic results, in combination with separate B and D genome studies, might suggest an early divergence of the Oryza ssp. by continental drift of Gondwanaland. O. long-istaminata MUG1 divergence from other AA diploids suggests that it might not be a direct ancestor of the African rice species.