• Mass Spectrometry Letters
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• 제13권3호
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• pp.49-57
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• 2022

During electrospray ionization mass spectrometry (ESI-MS) analysis of proteins, the addition of supercharging agents allows for adjusting the maximal charge state, affecting the charge state distribution, and increases the number of ions reaching the detector thus, improving signal detection. We postulate that in di-substituted arene isomers, molecules with higher polarizability values should generate greater interactions and hence elicit higher signal intensities. Polarizability is an electronic parameter which has been demonstrated to predict many chemical interactions. Many properties can be predicted based on charge polarization. Molecular polarizability is a vital descriptor for explaining intermolecular interactions. We employed DFT (density functional/Hartree-Fock hybrid model, B3LYP)-derived descriptors and computed molecular polarizability for ten disubstituted arene reagents, each set made up of three (ortho, meta, para) isomers, with reported use as supercharging reagents during ESI experiments. The atomic electronic inputs were ionization potential (IP), electron affinity (EA), electronegativity (𝛘), hardness (η), chemical potential (µ), and dipole moment (D). We determined that the para isomers showed the highest polarizability values in nine of the ten sets. There was no difference between the ortho and meta isomers. Polarizability also increased with increasing complexity of the substituents on the benzene ring. Polarizability correlated positively with IP, EA, 𝛘, η, and D but correlated negatively with chemical potential. This DFT study predicts that the para isomers of di-substituted arene isomers should elicit the strongest ESI responses. An experimental comparison of the three isomers, especially of larger supercharging molecules, could be carried out to establish this premise.

• 한국미생물·생명공학회지
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• 제46권2호
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• pp.135-144
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• 2018

The rapid increase in number and diversity of Extended Spectrum ${\beta}$-Lactamases (ESBLs) producing Enterobacteriaceae in natural aquatic environment is a major health concern worldwide. This study investigates abundance and distribution of ESBL producing multidrug resistant Enterobacteriaceae and molecular characterization of ESBL genes among isolates from highly polluted stretch of river Yamuna, India. Water samples were collected from ten different sites distributed across Delhi stretch of river Yamuna, during 2014-15. A total of 506 non duplicate Enterobacteriaceae isolates were obtained. Phenotypic detection of ESBL production and antibiotic sensitivity for 15 different antibiotics were performed according to CLSI guidelines (Clinical and Laboratory Standard Institute, 2015). A subset of ESBL positive Enterobacteriaceae isolates were identified by 16S rRNA gene and screened for ESBL genes, such as $bla_{CTX-M}$, $bla_{TEM}$ and $bla_{OXA}$. Out of 506 non-duplicate bacterial isolates obtained, 175 (34.58%) were positive for ESBL production. Susceptibility pattern for fifteen antibiotics used in this study revealed higher resistance to cefazolin, rifampicin and ampicillin. A high proportion (76.57%) of ESBL positive isolates showed multidrug resistance phenotype, with MAR index of 0.39 at Buddha Vihar and Old Delhi Railway bridge sampling site. Identification and PCR based characterization of ESBL genes revealed the prevalence of $bla_{CTX-M}$ and $bla_{TEM}$ genes to be 88.33% and 61.66%, respectively. Co-occurrence of $bla_{CTX-M}$ and $bla_{TEM}$ genes was detected in 58.33% of the resistant bacteria. The $bla_{OXA}$ gene was not detected in any isolates. This study highlights deteriorating condition of urban aquatic environment due to rising level of ESBL producing Enterobacteriaceae with multidrug resistance phenotype.

• 대한수의학회지
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• 제42권3호
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• pp.327-333
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• 2002

The study was carried out to examine the distribution and survival rate of Listeria monocytogenes (L monocytogenes) from various source of waters using improved isolation method. In comparision of enrichment media for isolation of L monocytogenes from water, the isolation rate and 50% detection limit of the pathogen were higher in UVM modified Listeria enrichment broth (UVM) than Listeria enrichment broth (LEB). On the other hand, when compared the selective media for isolation of the pathogen from water, the isolation rate was highest in culture at Oxford agar followed by Fraser agar, and LEB agar. In order to improve enrichment method, 100 ml of water samples with 0.1 CFU/ml of L monocytogenes was inoculated into 10 ml of UVM concentrated at 10-fold, and incubated for 24 h at $36^{\circ}C$. Isolated frequency of the pathogens in improved enrichment method completely corresponded with common (filter) method. Of a total mumber of 147 water samples from river, lake and sea, the pathogen was isolated from 1 of 39 (2.6%) river water samples and 1 of 75 (1.3%) sea water samples, but no pathogen was isolated from 33 lake water samples. Serotypes of 2 isolates were identified as type 1. L monocytogenes decreased in number from 7.2-7.4 to 4.2-4.7 log CFU/ml for 1 week poststorage (5 and $20^{\circ}C$), but the pathogens were able to be detected in river and sea water until 8 weeks after storage. However, in tap water, L monocytogenes were decreased to undetectable level after 2 weeks of storage.

• 한국대기환경학회지
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• 제21권6호
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• pp.573-583
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• 2005

Fugitive dust, which is emitted in the ambient air without first passing through a stack or duct designed to control flow, is frequently generated by means of wind erosion from storage yards at Pohang Steel Wokrs. The size distribution of fugitive dust is mostly in the range of coarse particulate which is deposited as soon as emitted and less harm to human health; however $20\%$ of fugitive dust contains PM 10 known as one of most harmful airborne pollutant. Consequently, effective control and reduction of fugitive dust is strongly requested by the local society, but it is not easy so far because the generation and dispersion of fugitive dust highly depends on meteorological conditions, and it being occurred for irregularity. This research presented a fugitive dust control system for each meteorological condition by providing statistical prediction data obtained from a statistical analysis on the probability of generating the threshold velocity at which the fugitive dust begins to occur, and the frequency occurring by season and by time of the wind direction that can generate atmospheric pollution when the dispersed dust spreads to adjacent residential areas. The research also built a fugitive dust detection system which monitors the weather conditions surrounding storage yards and the changes in air quality on a real-time basis and issues a warning message by identifying a situation where the fugitive dust disperses outside the site boundary line so that appropriate measures can be taken on a timely basis. Furthermore, in respect to the spraying of water to prevent the generation of fugitive dust from the storage piles at the storage yard, an advanced statistical meteorological analysis on the weather conditions in Pohang area and a case study of fugitive dust dispersion toward outside of working field during $2002\∼2003$ were carried out in order to decide an optimal water-spraying time and the number of spraying that can prevent the origin of fugitive dust emission. The results of this research are expected to create extremely significant effects in improving surrounding environment through actual reduction of the fugitive dust produced from the storage yard of Pohang Steel Works by providing a high-tech warning system capable of constantly monitoring the leakage of fugitive dust and water-spray guidance that can maximize the water-spraying effects.

• 한국동물위생학회지
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• 제36권1호
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• pp.31-36
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• 2013

Mycobacterium avium subsp. paratuberculosis is the pathogen of paratuberculosis called Johne's disease. Johne's disease is hardly eliminated because of its long latent period and continuous dissemination, so it is found in ruminants worldwide and can cause substantial economic losses in cattle. It has been reported in many studies on the distribution of Johne's disease in some provinces of Korea that not many, but noticeable numbers of infected cows have been detected since the first detection in 1984. The aims of this study was to investigate the prevalence of Johne's disease obtained from slaughtered cattle in central area of Gyeongnam province, Korea. In this study, the ELISA serum antibody test and PCR were employed on a total of 240 blood and ileac substrate samples from slaughtered cattle in two slaughtering and wholesale centers in Gyeongsangnam-do Livestock Veterinary Research Institute Central Branch. Out of the entire 240 blood samples, three (1.3%) were positive by ELISA, while five (2.1%) were suspected cattle. But ileac substrate samples, eight (3.3%) were positive by PCR. By breeds, positive rates of ELISA and PCR in Korean native cattle were 1.3% and 3.5%, respectively, but no positive cows were found in dairy cattle. By provinces, sero-positive rates of Gyeongnam and Gyeongbuk were 1.6% and 1.3%, respectively. And PCR positive rates of Gyeongnam, Gyeongbuk and other provinces were 2.4%, 5.0% and 2.8%, respectively. These results indicate that it requires the nationwide monitoring test and measure to deal with subclinically infected slaughtering cows.

• 한국환경보건학회지
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• 제44권5호
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• pp.444-451
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• 2018

Objectives: This study was carried out to provide safe seafood to the public through simultaneous analysis rapid inspections for residual veterinary drugs in 150 fishery products in 2016. Methods: Quinolones (9), Sulfonamides (14), Penicillins (2), Cephalosporins (3), Tetracyclines (4), Macrolides (4), Lincosamides (2), Pleuromutilin (1), Phenicols (4), benzylpyrimidines (2), Others (1) Malachite green (2), and Melamine (1) were analyzed for 49 species using by HPLC and HPLC-MSMS. Results: There were six unsuitable samples, five among fish and one for crustaceans. Within the standard detection were five fish. The antibiotics found were Quinolones (50%), Tetracyclines (33%) and Penicillins (17%). Conclusions: As a result of the experiment, there were six unsuitable samples, five for fish and one for crustaceans. The most prevalent antibiotics were Quinolones. The quinolone antibiotics are highly persistent in fish tissues, so they require more time than the withdrawal period for other common veterinary drugs. Careful attention is required when they are used in fish farms.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3949-3953
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• 2012

Head and neck cancers are amongst the commonest malignancies, accounting for approximately 20% of the cancer burden in India. The major risk factors are tobacco chewing, smoking and alcohol consumption, which are all preventable. This retrospective study presents data from the histopathology register for a five year period from 2002-2006 at Patna Medical College and Hospital, a tertiary care hospital drawing patients from the entire Bihar state, the 3rd most populous state of India with the majority of the population residing in rural areas. Incidence rates based on sex, age, site of lesion, including age standardized incidence rates for males and females, with mean age of presentation, distribution of histological variants and year wise trend were calculated. Out of 455 head and neck neoplasias, 241 were benign while 214 were malignant. The most common age group for all malignant biopsies was 7th decade for males and the 5th decade for females. Malignant cases were commoner in males than females with the male:female ratio of 3.1:1, which was found to be statistically significant by the chi-square (${\chi}^2$) test. The crude rate and age standardized incidence rate was 0.05 and 0.06 per 100,000 population respectively. Squamous cell carcinoma (SCC) contributed about 96% of all cases, with grade I being the most common. Larynx was the most common site for malignancy, the supraglottic region being its most commonly affected sub-site. This observed incidence patterns in the region are a reminder of widespread unawareness, low healthcare utilization with virtually non-existent cancer programs. It also underlines the need to advocate for reliable cost-effective programs to create awareness, for early detection and plan appropriate management strategies. There is a compelling demand for a cancer registry in this region as well as proper implementation of preventive measures to combat this growing threat of cancer, many of whose risk factors are preventable.

• 한국멀티미디어학회논문지
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• 제20권12호
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• pp.1960-1969
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• 2017

There have been ongoing researches to identify and analyze the patterns of electric power IoT data inside sensor nodes to supplement the stable supply of power and the efficiency of energy consumption. This study set out to propose an analysis process for electric power IoT data with the K-means algorithm, which is an unsupervised learning technique rather than a supervised one. There are a couple of problems with the old K-means algorithm, and one of them is the selection of cluster number K in a heuristic or random method. That approach is proper for the age of standardized data. The investigator proposed an analysis process of selecting an automated cluster number K through principal component analysis and the space division of normal distribution and incorporated it into electric power IoT data. The performance evaluation results show that it recorded a higher level of performance than the old algorithm in the cluster classification and analysis of pitches and rolls included in the communication bodies of utility poles.

• 대한화장품학회지
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• 제32권2호
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• pp.93-97
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• 2006

황색포도상구균이 정상인 피부의 경우 $2{\sim}25%$에서 검출되는 반면 아토피 피부염이 있는 소아와 어른에 있어 $78{\sim}100%$의 높은 비율로 검출되며, 황색포도상구균과 초항원으로 작용하는 독소가 아토피 피부염의 악화 및 발병기간에 중요한 역할을 하는 것으로 알려져 있다. 본 연구는 아토피 피부염 환자 피부의 황색포도상구균의 분석과 함께 아토피 피부염 환자의 연령, 성별, 발병 연령과 투병기간, 악화되는 계절 및 진물과 황색포도상구균과의 관계에 대하여 알아보고자 실시하였다. 아토피 피부염 환자 대부분(84%)에서 병변부에 S. aureus가 집락을 형성하고 있는 것으로 나타났으며, 대부분의 아토피 피부염 환자의 피부에 S. aureus가 분포하고 있음을 알 수 있었고 아토피 피부염 병변부의 진물과 S. aureus의 밀접한 관계를 확인할 수 있었다. 따라서 아토피 피부염 환자의 피부에서 황색포도상구균 및 초항원독소를 차단한다면 아토피 피부염의 개선에 많은 도움이 될 것으로 사료된다.

• 대한수의학회지
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• 제29권1호
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• pp.37-44
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• 1989

This paper dealt with the distribution of Shigella spp. on 5 piggeries in Taegu and Kyungpook during the period from August to October 1987. Isolated Shigella were examined for serogrouping, antimicrobial drug resistance and detection of R plasmid. Genetic properties of R plasmid in Shigella have examined to fertility inhibition (Fi) and gel electrophoresis was performed for the isolation of plasmid DNA. The results obtained were summarised as followings; 1. Of total 2,978 samples from 5 piggeries, 82 strains (2.8%) of Shigella spp. were isolated from 82 samples. The isolated strains were identified as S dysenteriae (60 strains), S flexneri (20 strains) and S sonnei (2 strains). 2. Of the 82 strains examined 67 (95.1%) were resistant to one or more antibiotics, such as ampicillin (Am), chloramphenicol (Cm), kanamycin (Km), nalidixic acid (Na), rifampicin (Rf), streptomycin (Sm), sulfademethoxine (Su), and tetracycline (Tc) and higher resistant to Su (90.2%), Sm (63.4%) and Tc (63.4%). 3. Of the 78 resistant Shigella strains 26 (33.3%) harbored conjugative R plasmids and the transfer frequency of Sm (50.0%), Cm(33.3%) resistance was much higher than that of the other drug resistance. 4. The most common resistant patterns were SmSuTc, Su and AmSmSuTc. 5. Out of the 26 Shigella R plasm ids examined for Fi, 14(53.8%) were $Fi^+$ and the remainder were $Fi^-$. 6. The plasmid DNA profiles in Shigella spp. (9 strains) isolated from pigs were confirmed as being 2 to 9 fragments by the gel electrophoresis. Their molecular size ranged 2.17 to 87.62 kilobase (Kb). All strains of Shigella spp. consisted in 15.4 Kb plasmids.