• Journal of Magnetics
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• v.16 no.4
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• pp.332-336
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• 2011

We studied the effect on the electronic and magnetic properties of the N defect in clean and Cu-doped wurtzite III-nitrides by using the first-principles calculations. When it is doped two Cu atoms in the nearest neighboring sites, the system of AlN, GaN, or InN with the N vacancy is energetically more favorable than that without the N vacancy site. When the Cu concentration increases, the total magnetic moment of a supercell becomes small. The ferromagnetism of Cu atom is very low due to the weak 3d-3d coupling. It is noticeable that the spin-exchange interaction between the Cu-3d and N defect states is important.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.184-188
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• 1987

Evidences that the mannose permease of Escherichia coli mediates the infection of N4 in early steps, were obtained as follows. First, A mutant strain of Escherichia coli which was resistant to both wild type N4 and lambda whose genome is Charon 4A containing human genomic fragments in its EcoR I site, could not use mannose efficiently. Second, N4 could not infect pel mutant strains which lack one or all of intact components of mannose permease. However, unknown alterations in N4 made it possible for the phage to infect pel mutant of E. coli. It also turned out to be clear that the receptor of N4 was different from that of lambda.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.525-526
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• 2018

• Journal of Magnetics
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• v.10 no.1
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• pp.23-27
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• 2005

The crystallographic and magnetic properties of a series of substitutions in nickel ferrite where the Fe³⁺ is replaced with In³⁺ have been investigated using X-ray diffraction (XRD) and Mössbauer spectroscopy. Information on the exact crystalline structure, lattice parameters, bond lengths and bond angles were obtained by refining their XRD profiles by a Rietveld method. All the crystal structures were found to be cubic with the space group Fd/3m. The lattice constants increased with In³⁺ concentration. The expansion of the tetrahedron was outstanding, indicative of the tetrahedral (A) site preference of larger indium ion. The Mossbauer spectra showed two sets of sextuplet originating from ferric ions occupying the tetrahedral sites and the octahedral (B) sites under the Neel temperature T_N. Regardless of the composition x, the electric quadrupole splitting was zero within the experimental error. At x = 0.2, the magnetic hyperfine fields increased slightly, which meant that the nonmagnetic indium ions occupied preferentially the A-site. At the same time, the intensity of the B-site sub-spectra decreased markedly at the elevated temperature, indicating that the occupation of the A site by indium induced a considerable perturbation on the B site.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.528-535
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• 2014

Objectives: This study compares the differences of fit factors before and after training on the N95 mask. The results will be utilized to suggest the need of providing effective training on respirator use. Methods: A total of 49 study subjects were tested, comprised of nurses from a general hospital and undergraduate nursing students from a medical school. Anthropometric measurements of face length and face width were compared with the NIOSH(National Institute for Occupational Safety and Health) panel. Fit factors(FF) were measured with TSI Portacount Pro+8038 before and after on-site training regarding the proper use of respirators. The FF pass/fail criterion was set at 100. Results: Two subjects(4.1 %) passed the fit test before training on use of the N95. However, 36(73.5%) of the 49 passed the test after training. Overall the FF(GM(GSD)) was 13.4(3.2) before training, but improved to 106.6(2.1) after training, which was statistically significant. These findings suggest the efficacy of educational intervention, and the performance of the direct on-site training proved to be better than that of the traditional educational methods. Conclusions: This study showed the effect of on-site training of the N95 respirator among health care workers(HCW). Therefore, providing effective training on the use of N95 for HCWs before their work assignments will greatly reduce exposure to harmful agents. It is recommended that fit testing be mandated to check for adequate protection being provided by the given respirators.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.205-210
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• 2013

Lumazine protein is a fluorescent protein isolated from the bioluminescent bacteria of Photobacterium species. To generate minimal size of lumazine protein with possessing fluorescent characteristic, the gene coding for the wild type N-terminal domain of lumazine protein (N-LumP 118) containing amino acids up to 118 from Photobacterium leiognathi was produced. In addition, the genes coding for the variant proteins of N-LumP 118, replaced with one tryptophan amino acid (N-LumP 118 V41W, S48W, T50W, D64W, and A66W), were also constructed by Polymerase Chain Reaction and Site Directed Mutagenesis. These proteins were expressed in Escherichia coli by transformation with recombinant plasmids and purified by 6X-His tagging system. Spectroscopic studies have show that the purified proteins are capable of binding to the fluorescent ligand 6,7-dimethyl-8-ribityllumazine, resulted in showing of fluorescent characteristic with the minimal size of protein. From these studies, the mutant proteins containing single tryptophan amino acid residue, possessing its own intrinsic flouophore character at the different position, will be able to the use as a probe for further studies to deduce their three dimensional structure and the binding modes.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.4
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• pp.138-142
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• 2016

Replication Protein A (RPA) is the eukaryotic single-stranded DNA binding protein. It involves in DNA replication, repair, and damage response. Among three subunits, RPA70 has a protein-protein binding domain (RPA70N) at the N-terminal. It has known that the domain recruits several damage response proteins to the damaged site. Also, it is suggested that there are more candidates that interact with RPA70N. Even though several studies performed on the structural aspects of RPA70N and its ligand binding, the backbone assignments of RPA70N is not available in public. In this study, we present the backbone assignments of RPA70N.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.341-346
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• 2007

Nest density was determined and tree and soil characteristics around Nycticorax nycticorax breeding sites and non-breeding sites on Bamsum Island in Seoul were analyzed from May 2005 to October 2006 to identify breeding site preferences of N. nycticorax and the effects of N. nycticorax nesting density on nesting tree structure and soil characteristics. N. nycticorax preferred trees of low height ($3.5{\sim}6$ m) and small diameter at breast height in high density Salix communities. Excrement of heron juveniles was dropped on the soil under the nests. The soil nutrient content under nests (P: 126.0 mg/kg, N: 202.8 mg/kg, EC: 549 ${\mu}S/cm$, pH 4.7) was much higher than that of control soils from Bamsum Island not enriched by heron excrement (P: 41.5 mg/kg, N: 42.0 mg/kg, EC: 342 ${\mu}S/cm$, pH 5.1). Formation of Salix communities on the shores of Bamsum Island is ongoing, and their structure has been directly influenced by annual flooding. After flooding, the nutrient content differences between heron-affected soils and control soils were not significant. This might be the reason that Salix communities on Bamsum were not affected by nesting herons as in other terrestrial communities where herons nest. This result indicates that flooding plays an important role in sustaining Salix communities on Bamsum Island where herons nest. The results of this study may increase understanding of N. nycticorax breeding behavior which may be useful for conservation planning.

• BMB Reports
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• v.36 no.6
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• pp.533-537
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• 2003

The nonsyndromic cleft lip and palate (NSCL/P) is a congenital deformity of multifactorial origin with a relatively high incidence in the oriental population. Various etiologic candidate genes have been reported with conflicting results, according to race and analysis methods. Recently, the ablation of the TGF-${\beta}3$ gene function induced cleft palates in experimental animals. Also, polymorphisms in the TGF-${\beta}3$ gene have been studied in different races; however, they have not been studied in Koreans. A novel A $\rightarrow$ G single nucleotide polymorphism (defined by the endonuclease SfaN1) was identified in intron 5 of TGF-${\beta}3$ (IVS5+104 A > G). It resulted in different genotypes, AA, AG, and GG. The objective of this study was to investigate the relationship between the SfaN1 polymorphism in TGF-${\beta}3$ and the risk of NSCL/P in the Korean population. The population of this study consisted of 28 NSCL/P patients and 41 healthy controls. The distribution of the SfaN1 genotypes was different between the cases and controls. The frequency of the G allele was significantly associated with the increased risk of NSCL/P [odds ratio (OR) = 15.92, 95% confidence interval (CI) = 6.3-41.0]. The risk for the disease increased as the G allele numbers increased (GA genotype: OR = 2.11, 95% CI = 0.38-11.68; GG genotype: OR = 110.2, 95% CI = 10.67 - 2783.29) in NSCL/P. A stratified study in patients revealed that the SfaN1 site IVS5+104A > G substitution was strongly associated with an increased risk of NSCL/P in males (p < 0.001), but not in females. In conclusion, the polymorphism of the SfaN1 site in TGF-${\beta}3$ was significantly different between the NSCL/P patients and the control. This may be a good screening marker for NSCL/P patients among Koreans.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.498-505
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• 2018

This study was aimed to investigate the effects of the type O foot-and-mouse disease vaccine (FMDV) on the incidence of abnormal meat such as granuloma or abscess formation at the injection site in pork and its associated economic losses. At 56 d of age, piglets were inoculated with FMDV by one of three administration routes: N-Neck (a conventional needle-syringe injection into the neck), N-Ham (a conventional needle-syringe injection into the ham), and Non-Neck (injection with a needle-free device into the neck). The injection sites were visually examined for the presence of a granuloma or abscess, and the incidence rate of abnormal meat was calculated. The gross weight of the portion of the pork carcasses condemned because of granuloma or abscess formation was measured and multiplied by the weekly sales price to calculate the total economic losses. After implementation of FMDV, the economic losses were approximately six times higher than before implementation. Granuloma or abscess formation was significantly higher in the N-Neck and Non-Neck groups, in which the vaccine was inoculated into the neck area, than in the N-Ham group (N-Neck and N-Ham vs Non-Neck, p<0.05). These results suggest that the incidence of lesions could be reduced if the ham route was used for vaccination.