• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.134-141
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• 2011

Two-hundred Bacillus cereus isolated from perilla leaf cultivation areas in Miryang, Korea were investigated for toxin genes and antibiotic susceptibility. Toxigenic patterns of isolates were identified to be 11 groups through toxin gene profiles. 21% of strains isolated from the perilla leaves had both enterotoxin and emetic toxin. Toxin genes entFM (100%), nheA (100%) and hblA, C, D (65.5%) were frequently found in the perilla leaves, whereas EM (21.0%) was less common. Most isolates were susceptible to 10 antibiotics, but they were highly resistant to penicillin (100%), ampicillin (100%), oxacillin (94.9%), amoxicillin-clavulanic acid (95.6%), cefazolin (78.2%), and rifampicin (58.0%). These results indicate that food-borne outbreak caused by B. cereus might lead to diarrhea and emetic syndromes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.960-964
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• 2007

This study was performed to examine the toxicity of Psoralea corylifolia L. by the single-dose oral toxicity tests in rat and bacterial reverse mutation assay. In single-dose oral toxicity tests, 5 mL ethanol extract of P. corylifolia L. were directly injected into 10 rats (5 males and 5 females) at a dosage of 2 g/kg. Death practice was not detected during breeding periods (14 days), and $LD_{50}$ was calculated over 2 g/kg. No difference were observed with control group in the growth rate and histological observations. In bacterial reverse mutation assay, his(-) Salmonella Typhimurium TA98, TA100, TA1535, TA1537 and trp(-) Escherichia coli WP2uvrA (pKM101) were used for assessing the toxicity of ethanol extracts of P. corylifolia L.. No significant difference in formation of the colonies and no dose-dependent increase was observed regardless of the addition of S9 mix. The results showed that ethanol extracts of P. corylifolia L. did not have single-dose oral toxicity and mutagenic toxicity.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.11
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• pp.1117-1124
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• 2011

In this paper, we implemented a Ka-band frequency synthesizer for millimeter wave seeker. We improved frequency synthesizer performance of phase noise, resolution and spurious using the DDS driven hybrid method The proposed frequency synthesizer has the bandwidth of 1 GHz, frequency switching time of below 9 ${\mu}s$, suppressed spurious level of below -68.9 dBc. phase noise of -113.58 dBc/Hz at offset 100 kHz and flatness of ${\pm}$0.7 dB.

• Journal of Veterinary Clinics
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• v.7 no.2
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• pp.489-495
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• 1990

The purpose of this study was to investigate the contamination rates of Keratinophilic fungi in soils In Chonju. From september to November 1986, 98 soil samples were collected at the school and children's play ground, dog barn, pig barn, cow barn, horse barn and fowl barn( total 33 sites ). The samples were collected at the different depths(0～2cm, 30cm, 50cm ) in each of the sites, respectively. Each sample was cultured at 25$^{\circ}C$ according to Modified hair baiting method by using horse mane hair as a bait. The results obtained were summerized as follows ; 1. Eighty one of the 98 soil samples were found to be positive for Keratinophilic fungi. 2. In the examination of keratinophilic fungi in 98 soil samples, the organisms isolated weie as follows; Microsporum gypseum 20, Trichophyton ajelloi 15, Chrysosporium tropicum 40, C. Keratinophilum 24, C. tuberculatum 6 and Chrysosporium spp. like organism 4 strains. 3. The positive rates of keratinophilic fungi in each of the depths were 87.9%(29/33) in surface layer, 90.9%(30/33) in middle layer and 68.8％(22/32) in deep layer. 4. The positive rates of Keratinophilic fungi in each of the sites were 100%(3/3) in horse barn 91.7％ (l1/12) in dog barn, 88.9%(16/18) in pig barn, 86.7%(13/15) in cow barn, 76.2%(16/21) in fowl barn and 75.9%(22/29) in school and children's play ground. 5. The isolation rates of M. gypseum, Pathogenic fungi for human and animals, were as follows ; 58.3％ in dog barn(surface layers 100％, middle layers 50％, deep layers 25％) and 16.7％ in pig barn(surface 33.3％, middle 16.7%, deep 0％). In the cow barn, the isolation rates were 13.3%(surface 40.0％, middle 0%, deep 0％) and 10% in horse barn(surface l00％, middle 100%, depp 100%). In the fowl barn, the isolation rates was 19.1%(surface 28.8%, middle 14.3%, deep 14.3%) and 3.5% in school and children's play ground(surface 0％, middle 0％, deep 11.1%).

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.457-462
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• 1998

A chiral pentadentate bis-amide ligand, 1,9-bis(S)-pyrrolidinyl-2,5,8-triazanonane-1,9-dio ne$(S,S-prodienH_2)$ has been synthesized from the reaction of bis(2-aminoethyl)amine(dien) and S-proline, and the structure of $[Co(S,S-prodien)H_2O]ClO_4$ has be en determined by single crystal X-ray diffraction. The geometrical structure of the Co(III) complex has been an αβ -form, where the dien moiety of ligand chelates to a facial in metal center, and the aqua ligand coordinates a cis site to the secondary nitrogen of dien. The Co-N(1), Co-N(3) distances of two amide moiety in S,S-prodien are shorter than the other Co-N(2), Co-N(4), and Co-N(5) distances because of the increased basicity of nitrogen in amide. The complex crystallizes in the monoclinic space group $P2_1$(#4), with a=7.838(1), b=12.675(1), c=9.710(1) Å, β=100.39(1) and z=2. Refinement gives the final R and $R_w$ values of 0.045 and 0.057, respectively for 2130 observed reflections. Based upon the CD and X-ray data, it is identified that the absolute configuration of the αβ -$[Co(S,S-prodien)H_2O]ClO_4$ has a Λ-form.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.303-309
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• 2003

This study was performed to investigate the antimutagenic and antioxidative activities of pine pollen with respect to the microbial mutation induced by various mutagens such as 1-NP, daunomycin, 2-NF, MNNG, NaN$_3$, 4NQO, 4-NOPD, AFB$_1$, Trp-P-1, 2-AF and oxidative mutagens such as t-BOOH, H$_2$O$_2$. Pine pollen, originally extracted with hexane, was reextracted with 70% methanol. The results obtained using the methanol extract, in terms of the antimutagenicity observed in relation to ten kinds of mutagens, showed that it exhibited 17.8, 82.2 and 80.9% inhibitory effects against daunomycin, AFB$_1$, and Trp-P-1, respectively, in Salmonella. typhimurium TA98 and a 72.3% inhibitory effect against AFB$_1$in S. tyPhimurium TA100. In terms of the antimutagenicity exhibited in relation to t-BOOH, a 72.3% inhibitory effect was observed, but no antimutagenicity was observed in relation to the other mutagens and strains. The methanol extract was further fractionated by chloroform, ethyl acetate, n-butanol. In S. typhimurium TA98, the chloroform(150 $\mu\textrm{g}$/plate) fraction showed strong antimutagenic effects of 55.6%, 93.7% and 93.5%, while the ethyl acetate(100 $\mu\textrm{g}$/plate) fraction showed 11.4%, 74.3% and 85.2% in relation to the mutagenicity induced by daunomycin, AFB$_1$and Trp-P-1, respectively. In S. typhimurium TA100, the chloroform and ethyl acetate fractions showed antimutagenic effects of 95.1% and 62.5%, respectively, on the mutagenicity induced by AFB$_1$. In S. typhimurium TA102, the chloroform fraction showed an antimutagenic effect of 93.6% on the mutagenicity induced by t-BOOH.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.9
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• pp.685-691
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• 2003

This work describes a 3 V 12b 100 MS/s CMOS digital-to-analog converter (DAC) for high-speed communication system applications. The proposed DAC is composed of a unit current-cell matrix for 8 MSBs and a binary-weighted array for 4 LSBs, considering linearity, power consumption, chip area, and glitch energy. The low-glitch switch driving circuit is employed to improve the linearity and the dynamic performance. Current sources of the DAC are laid out separately from the current-cell switch matrix core. The prototype DAC is implemented in a 0.35 urn n-well single-poly quad-metal CMOS technology. The measured DNL and INL of the prototype DAC are within $\pm$0.75 LSB and $\pm$1.73 LSB, respectively, and the spurious-free dynamic range (SFDR) is 64 dB at 100 MS/s with a 10 MHz input sinewave. The DAC dissipates 91 mW at 3 V and occupies the active die area of 2.2 mm ${\times}$ 2.0 mm.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.131-137
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• 2021

This study aimed at isolating lactic acid bacteria with anti-MRSA (methicillin-resistant Staphylococcus aureus) bacteriocin activity from fermented shrimp. We selected three strains, named Weissella sp. S1, S2, and S3, using analysis based on 16S rRNA gene sequences. All strains showed appropriate growth in an MRS medium containing 5% (w/v) NaCl and showed antibacterial activities against Bacillus cereus, Escherichia coli, Staphylococcus aureus, and MRSA. The strains exhibited similar growth rates at 0-5% NaCl, with approximate reduction in growth rate observed at 9% NaCl. Weissella sp. S1, S2, and S3 exhibited maximum growth rates at pH 7, 9, and 8, respectively. The crude bacteriocin was prepared from Weissella sp. S3 and subjected to characterization. The remaining activities after 30 min of exposure at each temperature were 100%, beyond 75%, and 49% at 4℃ and 37℃, 50℃ and 70℃, and 100℃, respectively. The remaining activities after 24 h of exposure at each pH were 100%, 75%, and 49% at pH 3 and 5, 7 and 9, and 10, respectively. Use of 50% (v/v) ethanol or isopropanol treatment did not diminish the antibacterial activity of the bacteriocin, while the 50% (v/v) hexane treatment reduced the activity by 51%. The molecular weight of the bacteriocin was nearly 6 kDa that was quantified using tricine-SDS-PAGE. Our findings suggest that Weissella sp. S3 may be considered a probiotic and useful source of antimicrobial substances in the development of bio-preservatives for food or in MRSA treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1953-1958
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• 2015

Background: In India, cancer accounts for 7.3% of DALY's, 14.3% of mortality with an age-standardized incident rate of 92.4/100,000 in men and 97.4/100,000 in women and yet there are no nationwide screening programs. Materials and Methods: We calculated age-standardized and age-truncated (30-69 years) detection rates for men and women who attended the Indian Cancer Society detection centre, New Delhi from 2011-12. All participants were registered with socio-demographic, medical, family and risk factors history questionnaires, administered clinical examinations to screen for breast, oral, gynecological and other cancers through a comprehensive physical examination and complete blood count. Patients with an abnormal clinical exam or blood result were referred to collaborating institutes for further investigations and follow-up. Results: A total of n=3503 were screened during 2011-12 (47.8% men, 51.6% women and 0.6% children <15 years) with a mean age of 47.8 yrs (${\pm}15.1yrs$); 80.5% were aged 30-69 years and 77.1% had at least a secondary education. Tobacco use was reported by 15.8%, alcohol consumption by 11.9% and family history of cancer by 9.9% of participants. Follow-up of suspicious cases yielded 45 incident cancers (51.1% in men, 48.9% in women), consisting of 55.5% head and neck (72.0% oral), 28.9% breast, 6.7% gynecological and 8.9% other cancer sites. The age-standardized detection rate for all cancer sites was 340.8/100,000 men and 329.8/100,000 women. Conclusions: Cancer screening centres are an effective means of attracting high-risk persons in low-resource settings. Opportunistic screening is one feasible pathway to address the rising cancer burden in urban India through early detection.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.91-96
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• 2005

In this paper, describes the design and performance of a 1.5 kW solid-state pulsed power amplifier, operating over 2.7-2.9 GHz at a duty of 10% and with a pulse width of 100 us for radar application. The solid-state pulsed power amplifier configures a series of 8-stage cascaded power amplifier with different RF output power levels. Low loss Wilkinson combiners are used to combine output powers of six 300W high power solid state modules. Tests show peak output power of 1.61 kW, corresponding to PAE of 26.2% over 2.7-2.9 GHz with pulse width of 100 us and a PRF of 1 kHz.