• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.259-265
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• 2008

This study was conducted to investigate incidence of extended-spectrum ${\beta}$-lactamase (ESBL) producing strains and characteristics of ESBL gene in pathogenic Escherichia coli isolated from poultry during the period from April 2003 to December 2005 in Korea. Among 203 isolates, 4 isolates (3 from broilers and 1 from layer) were confirmed as ESBL producing strains by double disk synergy test, polymerase chain reaction and sequencing for ${\beta}$-lactamase genes. $bla_{CTX-M-15}$ and $bla_{CMY-2}$ were detected in these 4 isolates and were transferred to recipient by conjugation, respectively. Also, these ESBL producing strains were associated with multiple drug resistance. In conclusion, these results exhibit incidence of CTX-M and CMY-2 ${\beta}$-lactamase in pathogenic E coli from poultry in Korea, and clinically important meaning in human. And they also suggest the needs for rapid and broad surveillance to monitor ESBL genes and R plasmid transferring resistant gene in poultry.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.1973-1976
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• 2008

Electronic photodepletion spectrum of dibenzo-18-crown-6 with a potassium ion ($K^+$-DB18C6) was obtained in the gas phase using electrospray ionization and quadrupole ion-trap reflectron time-of-flight mass spectrometry. The spectrum exhibited rather a broad absorption band at 36350 $cm^{-1}$, which was tentatively assigned as the origin of the S1 band. The photodepletion spectrum of $Cs^+$-DB18C6 was also obtained to elaborate the effects of metal cations on electronic and geometric structures of metal cation-DB18C6 complexes. We found that the S1 band of $Cs^+$-DB18C6 was red-shifted by 180 $cm^{-1}$ from that of $K^+$-DB18C6. With the results of quantum theoretical calculations using the density functional theory, we suggested that the red-shift arose mainly from weaker binding of $Cs^+$ to DB18C6 than that of K+, which resulted from a larger size of $Cs^+$ than that of the cavity in DB18C6.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.26-36
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• 2001

Smart sensors and actuators have recently been developed. In this study, first, small-diameter fiber Bragg grating (FBG) sensors developed by the author, whose cladding and polyimide coating diameters were 40 and $52{\mu}m$, respectively, were embedded inside a laminate without resin-rich regions around sensors and the deterioration of mechanical properties of the composite laminate. The small-diameter FBG sensor was embedded in $0^{\circ}$ ply of a CFRP laminate for the detection of transverse cracks in $90^{\circ}$ ply of the laminate. The reflection spectra from the FBG sensor were measured at various tensile stresses. The spectrum became broad and had some peaks with an increase of the transverse crack density. Furthermore, the theoretical calculation reproduced the change in the spectrum very well. These results show that the small-diameter FBG sensors have a potential to detect the occurrence of transverse cracks through the change in the form of the spectrum, and to evaluate the transverse crack density quantitatively by the spectrum width. On the other hand, shape memory alloy (SMA) films were used to suppress the initiation and growth of transverse cracks in CFRP laminates. Pre-strained SMA films were embedded between laminas in CFRP laminates and then heated to introduce the recovery stress in SMA films and compressive stresses in the weakest plies ($90^{\circ}$ ply). The effects of recovery stresses are demonstrated in the experiments and well predicted using the shear-lag analysis and the nonlinear constitutive equation of SMA films.

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2060-2065
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• 2016

Characteristics of E. coli O157:H7-specific infection bacteriophages (O157 coliphages) and broad-host-range bacteriophages for other E. coli serotypes (broad-host coliphages) were compared. The burst sizes of the two groups ranged from 40 to 176 PFU/infected cell. Distributions of the virulence factors stx1, stx2, ehxA, and saa between the two groups were not differentiated. Broad-host-range coliphages showed lower stability at $70^{\circ}C$, in relation to O157 coliphages. However, O157 coliphages showed high acid and ethanol tolerance by reduction of only 22% and 11% phages, respectively, under pH 3 and 70% ethanol for 1 h exposure. Therefore, these results revealed that the O157 coliphages might be more stable under harsh environments, which might explain their effective infection of the acid-tolerant E. coli O157:H7.

• KIEE International Transactions on Electrophysics and Applications
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• v.11C no.4
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• pp.138-141
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• 2001

The fluorescence emission spectrum of Cr$^{3+}$ doped BeAl$_{6}$ O$_{10}$ crystals at 300 K contains a broad band, three R-like lines and another emission lines. It has been identified by a lifetime resolution spectroscopic technique that there are three kinds of single-Cr$^{3+}$ centers, Cr(I), Cr(II), Cr(III), in this crystal. Cr(I) and Cr(II) are high-crystal field centers responsible for the three main "R-lines", and Cr(III) is a low-crystal field center responsible for the main broad band emission. The structures of these luminescent centers are reported.ted.

• Journal of Yeungnam Medical Science
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• v.37 no.4
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• pp.341-344
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• 2020

Hereditary neuropathy with liability to pressure palsy (HNPP) is a rare neurological genetic disease caused by deletion of the peripheral myelin protein 22 gene and presents in childhood or young adulthood. We report four cases of HNPP with typical and rare presentations, reflecting the broad clinical spectrum of this disease. Two patients presented with mononeuropathies that are frequently observed in HNPP; the remaining two presented with bilateral neuropathy or mononeuropathy anatomically present in the deep layer. This reflects the broad clinical presentation of HNPP, and clinicians should differentiate these conditions in young patients with monoparesis or bilateral paresis. Although HNPP is currently untreatable, early diagnosis in the emergency department can lead to early detection, eventually resulting in less provocation and recurrence which may cause early motor nerve degeneration.

• Journal of electromagnetic engineering and science
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• v.8 no.2
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• pp.41-46
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• 2008

A bandwidth and power efficient high speed ubiquitous sensor network(USN) for realizing a ubiquitous society is a great challenge for researcher community. In this paper we incorporate a cooperative transmission protocol within a special type of multi-code modulation to meet these requirements. Multi-code(Mc) modulation has been developed for high-speed data transmission over wireless channels. We proposed a new class of orthogonal codes for multi-code modulation which is an orthogonal subset of orthogonal codes(OSOC). Our proposed OSOC structure allows us to use only one relay to cooperate M nodes that effectively reduces the bandwidth and power requirement. This protocol is similar to spread-spectrum(SS) technique that can reduce both broad and narrow band jamming.

• Journal of the Korean Magnetic Resonance Society
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• v.9 no.1
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• pp.21-28
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• 2005

$^{11}B$ nuclear magnetic resonance (NMR) measurements have been performed to investigate electronic structures and vortex states of $M_gB_2$ superconductor. The central transition shows a narrow peak down to 25 K at 3.15 T. Below 25 K, an extra line starts to show up and dominates. The extra line is broad and asymmetric with a long tail in the high frequency side, which confirms that this originates from vortex pinning below the irreversibility temperature. From temperature evolution of the fraction and linewidth of the broad portion, temperature dependence of coherence length and penetration depth are extracted.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.55.4-55.4
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• 2016

We observed 10 Class I sources as part of the IGRINS (Immersion GRating INfrared Spectroscoph) Legacy Program, "IGRINS Survey of Protoplanetary Disks (PI: Jeong-Eun Lee)". Unlike other Class I sources, IRAS 16316-1540 shows broad absorption features in the near-infrared spectra (H and K bands). The broadened absorption features have been detected toward FU Orionis-type objects. Boxy or double-peaked absorption profiles can be produced by a Keplerian disk that has the hot mid-plane heated by a burst mass accretion. We could fit the broad absorption features of IRAS 16316-1540 with a K5 V template stellar spectrum convolved with a disk rotation profile of 45 km s-1. Therefore, rotationally broadened absorption features detected in this Class I source suggest that the episodic accretion process occurs from the early stage of star formation.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.318-323
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• 2007

Electronic photofragmentation spectrum of protonated tyrosine-alanine dipeptide ions(YAH+) was obtained in the wavenumber region of 34500~36700 cm-1 using a quadrupole ion trap time-of-flight mass spectrometer (QIT-TOFMS). YAH+ ions were produced by electrospray ionization, stored in the ion trap and then irradiated by ultraviolet laser pulses which induced photofragmentation of the ions. The electronic photofragmentation spectrum was obtained by monitoring the photodissociation yields of YAH+ ions as a function of the laser wavelength. The spectrum exhibited two broad peaks which were assigned as S1 and S2 by theoretical calculations using a time-dependent density functional method. The broad widths of the peaks in the spectrum were explained by the overlaps of the peaks originated from various conformers of YAH+ ions which were present in the gas phase at room temperature and also by the contributions of the hot bands.