• Korean Journal of Clinical Laboratory Science
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• v.37 no.3
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• pp.149-154
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• 2005

Fifty-one extended-spectrum-${\beta}$-lactamase(ESBL) producing Klebsiella pneumoniae strains were isolated from national university hospitals. All K. pneumoniae strains showed resistance to broad-spectrum antibiotic and most of them presented resistance to amikacin, gentamicin and ciprofloxacin. The results of amplified polymorphic DNA (RAPD) pattern for randomly isolated fifty-one strains were as follows; both twenty-one strains from Chungnam National University hospital and ten strains from Chungbuk National University hospital showed RAPD type Ia and Ib. However, twenty strains isolated from Gyeongsang National University hospital belonged to RAPD type IIa and IIb. All isolates were divided into four molecular types and showed high level of genetic diversity. These results suggested that RAPD analysis provided a rapid and simple method for analysing genotypes of ESBL.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.3
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• pp.199-203
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• 2019

The penetration depth of a hypervelocity jet exceeding 4 km/s is described by the density ratio of the jet and the target. In the case of the same density, the difference in strength between the targets does not affect the penetration depth difference. This study focuses on the "strength irrelevance" of such a hypervelocity jet. For this purpose, the change of crater pressure caused by shaped charge jet(SCJ) was calculated by finite element analysis and the possibility of polymorphic phase transition of steel material was investigated. Hypervelocity jets were found to cause polymorphic phase transitions in the steel target craters, and the decrease in the fracture toughness of the target is predicted as the cause of the strength irrelevance.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.421-428
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• 2020

Tamarind (Tamarindus indica L.) is one of the multipurpose tree species distributed in the tropical and sub-tropical climates. It is an important fruit yielding tree that supports the livelihood and has high social and cultural values for rural communities. The vegetative, reproductive, qualitative, and quantitative traits of tamarind vary widely. Characterization of phenotypic and genetic structure is essential for the selection of suitable accessions for sustainable cultivation and conservation. This study aimedto examine the genetic relationship among the collected accessions of sweet, red, and sour tamarind by using Random Amplified Polymorphic DNA (RAPD) primers. Nine accessions were collected from germplasm gene banks and subjected to marker analysis. Fifteen highly polymorphic primers generated a total of 169 fragments, out of which 138 bands were polymorphic. The polymorphic information content of RAPD markers varied from 0.10 to 0.44, and the Jaccard's similarity coefficient values ranged from 0.37 to 0.70. The genetic clustering showed a sizable genetic variation in the tamarind accessions at the molecular level. The molecular and biochemical variations in the selected accessions are very important for developing varieties with high sugar, anthocyanin, and acidity traits in the ongoing tamarind improvement program.

• Journal of Forest and Environmental Science
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• v.25 no.2
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• pp.93-100
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• 2009

In Malaysia, Labisia pumila Benth & Hook f, popularly known as 'Kacip Fatimah' has been used traditionally to treat various elements of the woman's health in Malay community. The objective of this study was to develop randomly amplified polymorphic DNA (RAPD) based DNA markers for the identification of L. pumila and to distinguish its three varieties from each other. Total DNA from nine accessions of L. pumila was extracted by CTAB method and polymerase chain reactions (PCR) were carried out to amplify the segments of DNA using different primers to develop DNA barcode using RAPD technique. To find out variety-specific DNA marker/s, twenty different 10-mer primer sequences with annealing temperature from 36-$40^{\circ}C$ were evaluated in triplicate. Out of 20 random primers, two primers (OPA-1 and OPA-2/A10) were selected which produced reliable RAPD band patterns. To have DNA based handle, two RAPD amplification products were cloned and sequenced to determine the identity of the DNA. RAPD analysis using two random primers generated 72 discrete bands ranging in size 200 bp-3,000 bp. Fifty nine of these were polymorphic loci (82%) and thirteen were non-polymorphic loci (18%). A total of 32 bands polymorphic loci (72%) were amplified with primer OPA-1 and analyzed by cluster analysis and UPGMA (Unweighted Pair Group Method with Arithmetic) to present a dendogram depicting the degree of genetic relationship among nine accessions of L. pumila. Our results shows the reasonable genetic diversity among the L. pumila varieties and within varieties; and two RAPD marker sequences obtained could be used to identify L. pumila at species level.

• Research in Plant Disease
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• v.13 no.3
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• pp.137-144
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• 2007

Fifty nine strains of Agrobacterium vitis, the causal agent of crown-gall disease on grapevine, originating from different geographical regions and 16 grapevine cultivars including 35 Kyoho cultivar of Korea, were characterized by PCR polymorphic analysis using Universal Rice Primer(URP). Of 12 URP primers, primers URP1F, URP2R, URP2F, and URP4R, URP17R were available for detecting PCR polymorphic bands among the A. vitis strains. PCR polymorphic bands produced by primers URP2F and URP17R were profiled to 12 strain types. A. vitis strains originated from Kyoho cultivar of grapevine showed relatively simple genetic diversify of the four PCR types, while the A. vitis strains originated from other grapevine cultivars and type culture strains showed various genetic diversity with 8 types. Unweighted Pair-Group Method with Arithmetic mean(UPGMA) cluster analysis using the URP-PCR polymorphic bands showed 59.4. vitis strains are genetically clustered into large seven groups.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.142-148
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• 1999

This research describes the construction of a site index equation and curves for Douglas-fir plantation (Pseudotsuga menziesii Mirb. Franco) in Nelson, New Zealand. The data sets of 146 Permanent Sample Plots (PSP) were used to build the model, and it was developed using the difference equation method. Parameter estimates were obtained using the non-linear routine of the SAS, PROC NLIN procedure. Of the models tested, a variant of the Schumacher polymorphic yield function showed the higher precision of fitting. About 95% of the observations used to fit the model could be predicted within ${\pm}1.2m$ of the actual values. Therefore, polymorphic family of site index curves, which reflect different shapes for the different site index classes, were derived from the Schumacher equation. It was found that the polymorphic site index equation was more accurate than the anamorphic equation in this study.

• The KIPS Transactions:PartC
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• v.10C no.7
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• pp.843-850
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• 2003

Script viruses are easy to make a variation because they can be built easily and be spread in text format. Thus signature-based method has a limitation in detecting script viruses. In a consequence, many researches suggest simple heuristic methods, but high false-positive error is always being an obstacle. In order to overcome this problem, our previous study concentrated on analyzing data flow of codes and has low-false positive error, but still could not detect a polymorphic virus because polymorphic virus loads self body and changes it before make a descendent. We suggest a heuristic detection method which expands the detection range of previous method to include polymorphic script viruses. Expanded data flow analysis heuristic has an expanded grammar to detect Polymorphic copy Propagation. Finally, we will show the experimental result for the effectiveness of suggested method.

• The KIPS Transactions:PartC
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• v.9C no.2
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• pp.149-156
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• 2002

Current vaccine program which scans virus code patterns has a difficult to detect the encrypted viruses or polymorphic viruses. The decryption part of polymorphic virus appears to be different every time it replicates. We must monitor the behavior of the decryption code which decrypts the body of the virus in order to detect these kinds of viruses. Specialty, it is not easy for the existing methods to detect the virus if the virus writer has modified the loop count of execution intentionally. In this paper, we propose an advanced emulator using a new algorithm so as to detect various kinds of polymorphic viruses. As a result of experiment using advanced emulator, we found that our proposed method has improved the virus detecting rate about 2%. In addition, our proposed system has a merit that it runs on not only MS-Windows but also Linux, and Unix-like Platform.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1664-1672
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• 2019

Objective: This study aimed to measure genetic diversity and to determine the relationships among fourteen goose breeds. Methods: Microsatellite markers were isolated from the genomic DNA of geese based on previous literature. The DNA segments, including short tandem repeats, were tested for their diversity among fourteen populations of geese. The diversity was tested on both breeds and loci level and by mean of unweighted pair group method with arithmetic mean and structure program, phylogenetic tree and population structure were tested. Results: A total of 108 distinct alleles (1%) were observed across the fourteen breeds, with 36 out of the 108 alleles (33.2%) being unique to only one breed. Genetic parameters were measured per the 14 breeds and the 9 loci. Medium to high heterozygosity was reported with high effective numbers of alleles (Ne). Polymorphic information contents (PIC) of the screened loci was found to be highly polymorphic for eleven breeds; while 3 breeds were reported moderately polymorphic. Breeding coefficient ($F_{IS}$) ranged from -0.033 to 0.358, and the pair wise genetic differentiation ($F_{ST}$) ranged from 0.01 to 0.36 across the fourteen breeds; for the 9 loci observed and expected heterozygosity, and Ne were same as the breeds parameters, PIC of the screened loci reported 6 loci highly polymorphic and 3 loci to be medium polymorphic, and $F_{IS}$ ranged from -0.113 to 0.368. In addition, genetic distance estimate revealed a close genetic distance between Canada goose and Hortobagy goose breeds by 0.04, and the highest distance was between Taihu goose and Graylag goose (anser anser) breed by 0.54. Conclusion: Cluster analyses were made, and they revealed that goose breeds had hybridized frequently, resulting in a loss of genetic distinctiveness for some breeds.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.4
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• pp.29-39
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• 2009

In order to respond against worms which are malicious programs automatically spreading across communication networks, worm detection approach by generating signatures resulting from analyzing worm-related packets is being mostly used. However, to avoid such signature-based detection techniques, usage of exploits employing mutated polymorphic types are becoming more prevalent. In this paper, we propose a novel static analysis approach for detecting the decryption routine of polymorphic exploit code, Our approach detects a code routine for performing the decryption of the encrypted original code which are contained with the polymorphic exploit code within the network flows. The experiment results show that our approach can detect polymorphic exploit codes in which the static analysis resistant techniques are used. It is also revealed that our approach is more efficient than the emulation-based approach in the processing performance.