• Journal of Sericultural and Entomological Science
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• v.34 no.2
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• pp.26-31
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• 1992

Flacherie virus (FV) and Densonucleosis virus (DNV) of the silkworm, Bombyx mori, which give the most severest damage to the silk production in korea, were fed on the mulberry wild silkworm, Bombyx mori mandarina, the mulberry pyralid, Gryphodes phyloalis, and the American fall webworm, Hypantria cunea, to investigate cross infectivity by serological and histopathological at observation. By the Ouchterlony's double difusion test the mulberry wild silkworm was infected with both FV and DNV type 1 (DNV-1) and the mulberry pyralid with DNV-1, so those were confirmed the cross infection. But the American fall webworm was not recognized the cross infection by the same method. The infection and multiplication of the FV in the mulberry wild silkworm was observed in the cytoplasm of the goblet cell with the appearance of the virus-specific vesicle. In DNV-1 infection to the mulberry wild silkworm and the mulberry pyralid, the nuclei of columnar cell in the midgut of both insects was hypertrophied and the nuclei of midgut cell of the mulberry pyralid positively stained with the feulgen stain. Multiplication of DNV-1 in the midgut cell of the mulberry wild silkworm was replicated in two different patterens as linear arrays and large masses, while that of DNV-1 in the muberry pyralid was multiplied as virus masses in several portion of the nuclei of the midgut cell.

• Journal of KIISE:Information Networking
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• v.35 no.4
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• pp.251-267
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• 2008

In this paper, we present a distributed topology control algorithm for constructing an optimized topology having a minimal search-time in unstructured peer-to-peer network. According to the proposed algorithm, each node selects the best nodes having higher hit-ratio than other nodes as many as the number being exponentially proportional to the hit-ratio of the node itself, and then it connects to them. The ensemble behavior of the proposed algorithm is very similar to the recrystrallizing phenomenon that is observed in nature. There is a partial order relationship among the hit-ratios of most nodes of constructed topology. Therefore once query message visits a node, it has a higher hit-ratio than the node that was visited last by the message. The query message even sent from freeloader can escape to the node having high hit-ratio by one hop forwarding, and it never revisits any freeloader again. Thus the search can be completed within a limited search time. We also propose the Chain-reactive search scheme using the constructed topology. Such a controlled multicasting reduces the query messages by 43 percent compared to that of the naive Gnutella using broadcasting, while it saves the search time by 94 percent. The search success rate of the proposed scheme is 99 percent.

• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1252-1255
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• 2005

Abnormalities in the levels of thyroxine-binding globulin (TBG) are not associated with clinical disease and they do not require treatment. Congenital TBG deficiency is inherited in an X-linked manner. To date, some complete and partial TBG variants and one polymorphism have been identified by analysis of the TBG gene. Two male neonates were referred to us because of their low $T_4$ levels that were noted on the neonatal screening test. They showed normal levels of free $T_4$ and TSH. Their serum TBG was not detectable and those values of their parents were within the normal ranges. The genomic DNA was extracted from their white blood cells and the four coding exons of the TBG gene were amplified by using polymerase chain reaction. Sequencing of the four coding regions and all the intron/exon junctions revealed a single nucleotide deletion of the first base of the codon 352 of the mature protein in both of the neonates. This mutation resulted in a frameshift and a premature stop codon (TGA) 374. Their mothers were shown to be heterozygotes. We detected a single nucleotide deletion resulting in a frameshift in two male Korean neonates who had complete TBG deficiency.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1358-1363
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• 2009

Purpose:The aim of this study was to determine the prevalence of asymptomatic nasopharyngeal carriages in children using a multiplex reverse transcriptase-polymerase chain reaction (mRT-PCR) assay kit. Methods:We obtained nasopharyngeal swabs from 33 children without any underlying disease from July 25 to July 28, 2008. The children were free from the signs of respiratory tract infections at the time of sampling. DNA was extracted from the swabs and subjected to multiplex RT-PCR using a primer set for the detection of pneumococci ($Seeplex^{(R)}$ PneumoBacter ACE Detection Seegene, Seoul, Korea). The amplified PCR products were separated on 2% agarose gels and stained with either ethidium bromide or screen tape system (Lab901 Scotland, UK). Results:A total of 33 children (male, 15 female, 18) aged between 3.2 and 16.3 (median, 8.2) years were included in this study. The mRT-PCR detected colonized bacteria (Streptococcus pneumoniae, Hemophilus influenzae, Chlamydia pneumoniae, and Bordetella pertussis) in 30 children (90.9%). Of these, 13 children (39.4%) showed more than 2 bacteria: 12 children were positive for 2 bacteria (S. pneumoniae and H. influenzae) and 1 child was positive for 3 bacteria (S. pneumoniae, H. influenzae, and C. pneumoniae). Conclusion:mRT-PCR was found to be a sensitive tool for the detection of asymptomatic nasopharyngeal carriages. Clinical significances of the bacteria detected by mRT-PCR will have to be evaluated in the future.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.217-225
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• 2014

Telomeres are the ends of the eukaryotic chromosomes and consist of a tandem repetitive DNA sequence and shelterin protein complex. The function of telomere is to protect chromosome. Telomere length in somatic cells tends to decrease with organismal age due to the end replication problem. However, several factors at the genetic, epigenetic and environmental level affect telomere length. In this study, we estimated heritability of telomere length and investigated inheritance of telomeres in a chicken. Telomere length of lymphocytes was analyzed by semi-quantitative polymerase chain reaction using telomere primer and quantitative fluorescence in situ hybridization using telomeric DNA probe. In results, heritability of telomere length was estimated 0.9 at birth by offspring-parent regression analysis and was estimated 0.03 and 0.04 at 10 and 30 weeks old, respectively, by parental variance analysis. There was a significant positive correlation in telomere length between father and their offspring (r=0.348), and mother and their offspring (r=0.380). In inheritance patterns of telomere length, the influence of paternal and maternal effect on their offspring was similar. The influence of inherited telomeres on male and female progeny was also roughly alike. These results implicated that imprinting of parental telomere length was regulated by autosomal genes, not sex linked genes. In addition, telomere length of offspring at birth did not differ along with their maternal age. Thus, maternal age does not affects telomere length in their offspring at birth owing to cellular reprogramming at early embryonic stage.

• Korean Security Journal
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• no.13
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• pp.507-528
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• 2007

June 2006, five korean oil workers, three who worked for Daewoo and two for Korea Gas, released after being held hostage by separatist militants in Nigeria. The kidnapping was happened in the Niger Delta where armed separatists are demanding a larger share in oil revenues and compensation for environmental destruction due to oil exploration. Seven months later, nine Korean pipeline workers of Daewoo together with a Nigerian were kidnapped again and safely released thanks to the efforts of the company and the Korean government. These two kidnapping incidents have shown that companies engaged in the overseas business are not safe any more from the terrorist attacks and has given an invaluable lesson that the company having an intention to go abroad for business should take all possible anti and counter-measures against terrorism. The main purpose of this study is to suggest a guideline for the establishment of counter-terrorism and security strategy against terrorist attacks on the private companies at the overseas. In order to foster a better understanding of the problem, a brief history of terrorism is presented in the first part. In addition, this study analyses and describes the variations of terrorist attacks against private companies together with the terrorism related environment of Korea. Based on the outcome of the study, this paper takes a global view and perspectives of terrorist attacks against private companies and suggests consideration for the future.

• Biomedical Science Letters
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• v.6 no.3
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• pp.201-208
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• 2000

The vancomycin, one of the family of glycopeptide antibiotics, inhibits the synthesis of bacterial cell wall peptidoglycan and has been widely used against gram-positive bacterial infections, especially for a treatment of methicillin resistant S. aureus infection. However, clinical isolate which was intermediately resistant to vancomycin (Mu50: MIC 8 $\mu\textrm{g}$/ml) was isolated in recent years. In this study we performed vancomycin susceptibility test with the increment method and population analysis with clinical isolates S. aureus. Also we did several kinds of tests with three selected isolates (s129: MIC 7 $\mu\textrm{g}$/ml, s134: MIC 7 $\mu\textrm{g}$/ml, s135: MIC 8 $\mu\textrm{g}$/ml) to find out possible mechanism of vancomycin resistance. As a result, the prevalence of vancomycin resistant S. aureus isolates among S. aureus strains resistant to methicillin was 23.3% (25/107). The vancomycin resistances of isolated strains of S. aureus were between those of Mu5O and Mu3 strains. By PCR analysis, none of the isolates with decreased vancomycin susceptibility contained known vancomycin resistant genes such as vanA, vanB, vanC1, vanC2, and vanH. Major bands of 81 kDa, 58 kDa, 33 kDa, 28 kDa were demonstrable in whole cell lysates by SDS-PAGE from all three isolates as well as reference strains. And especially,45 kDa protein was overproduced in Mu50 strains. Among them increased production of NAD$^{+}$-linked-$_{D}$-lactate dehydrogenase (dnLDH) were detected from one clinical strain (s135) and Mu5O strain. From these data, we suggest that the mechanism of vancomycin resistance in these isolates are distinct from that in enterococci.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.152-158
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• 2000

Background : No association between schizophrenia and dopamine D4 receptor polymorphisms have been reported. Despite these results, it is premature to exclude the association. It has been suggested that the susceptibility to develop schizophrenia could result from variation at a number loci which may interact or coact with each other. Therefore, we investigated a possible association of combinations of exon III 48bp polymorphism[D4E3] and exon I 12bp polymorphism of the DRD4 gene [D4E1] with schizophrenia. Methods : 207 unrelated Korean schizophrenic patients and 191 healthy controls were recruited. DRD4 genotype was established using the polymerase chain reaction. Statistical analysis consisted of ${\chi}^2$ tests for Hardy-Weinberg proportions and genotypic and allelic frequencies in the patients and control groups. Results : There were no statistically significant differences in the each polymorphisms between schizophrenics and controls. And all genotype frequencies were within Hardy-Weinberg expectations. When the combinations of the polymorphism in schizophrenia and controls were compared, however, there were significant differences at $A1A2^*2/4$ in the distributions of the combinations of D4E1 and D4E3(p<0.01). Conclusions : These findings suggest that the certain combination of D4E1 and D4E3($A1A2^*2/4$) has the protective role to a susceptibility for schizophrenia.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.509-521
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• 1994

This study is an effort to develop computer simulation model that produce precipitation patterns from stochastic model. A stochastic model is formulated for the process of daily precipitation with considering the sequences of wet and dry days and the precipitation amounts on wet days. This study consists of 2 papers and the process of precipitation occurrence is modelled by an alternate renewal process (ARP) in paper (I). In the ARP model for the precipitation occurrence, four discrete distributions, used to fit the wet and dry spells, were as follows; truncated binomial distribution (TBD), truncated Poisson distribution (TPD), truncated negative binomial distribution (TNBD), logarithmic series distribution (LSD). In companion paper (II) the process of occurrence is developed by Markov chain. The amounts of precipitation, given that precipitation has occurred, are described by a Gamma. Pearson Type-III, Extremal Type-III, and 3 parameter Weibull distribution. Daily precipitation series model consists of two models, A-Wand A-G model, by combining the process of precipitation occurrence and a continuous probability distribution on the precipitation of wet days. To evaluate the performance of the simulation model, output from the model was compared with historical data of 7 stations in the Nakdong and Seomjin river basin. The results of paper (1) show that it is possible to design a model for the synthetic generation of IX)int precipitation patterns.

• Pediatric Infection and Vaccine
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• v.18 no.1
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• pp.61-67
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• 2011

Purpose : This study was performed to investigate the epidemiologic characteristics of human bocavirus (HBoV)-associated lower respiratory tract infections (LRTIs) in children. Methods : Nasopharyngeal aspirate samples were obtained from 658 children who had been hospitalized for LRTIs in Seoul National University (SNU) Children's Hospital and SNU Bundang Hospital from March 2000 to September 2005. Multiplex RT-PCR was performed to detect 11 respiratory viruses including respiratory syncytial virus, adenovirus, rhinovirus, parainfluenza viruses 1 and 3, influenza viruses A and B, human metapneumovirus, HBoV, human coronavirus (HCoV) OC43/ 229E, and HCoV-NL63. Clinical data were reviewed retrospectively. Results : Overall, respiratory viruses were detected in 325 (49.4%) among 658 patients. HBoV was detected in 62 cases (9.4%) and was responsible for 19.1% of virus-positive cases. HBoV was prevalent among infants and young children aged from 3 months to 5 years with the mean age of 25.3 months. Co-detection of HBoV and other respiratory viruses was observed in 37.1% which is significantly higher than average co-detection rate (12.3%) among overall virus-positive cases (P=0.000). HBoV was identified mainly in late spring and early summer from May to July. Conclusion : This study describes epidemiologic features of HBoV in Korean children compared with those associated with other respiratory viruses. HBoV was prevalent among LRTIs in childhood, especially in late spring and early summer season in Korea.