• Food Science of Animal Resources
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• v.36 no.6
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• pp.779-786
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• 2016

This study aimed to evaluate the prevalence of Listeria monocytogenes on livestock farms in Korea and determine their serotypes and genetic correlations. Twenty-five livestock farms in Korea (central: 15, south west: 7, south east: 3) were visited 2-3 times, and 2,018 samples (feces: 677, soil: 680, silage: 647, sludge: 14) were collected. Samples were enriched in LEB (Listeria enrichment broth) and Fraser broth media, and then plated on Palcam agar. The isolates were identified by PCR and 16S rRNA gene sequencing. Then, the sero-types, presence of virulence genes (actA, inlA, inlB, plcB, and hlyA), and antibiotic resistance were determined. Genetic correlations among the isolates were evaluated by analyzing the restriction digest pattern with AscI. Of the 2,018 samples, only 3 (0.15%) soil samples (FI-1-FI-3) from 1 farm in the south east region were positive for L. monocytogenes. Based on biochemical tests and multiplex PCR, the serotype of the isolates were 4ab (FI-1 and FI-3) and 3a (FI-2), which are not common in foodborne L. monocytogenes. The 3a sero-type isolate was positive for all tested virulence genes, whereas the 4ab serotype isolates were only positive for hlyA, actA, and inlA. The isolates were resistant to all 12 tested antibiotics, especially FI-3. The genetic correlations among the isolates were 100% for those of the same serotype and 26.3% for those of different serotypes. These results indicate that the prevalence of L. monocytogenes on livestock farms in Korea is low; however, the isolates are pathogenic and antibiotic resistant.

• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.393-400
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• 2011

The needs for high strength structural materials have recently increased, because construction and cost efficiencies are demanded by the costumers. But, the use of high strength reinforcing bars requires longer development and splice lengths compared to normal strength bars. This restriction may cause reduction in construction efficiency and require more complicated details. The purpose of this paper is to evaluate the bond strength on the rib shape of reinforcing bars to decrease development and splice lengths of high strength reinforcements. Total of 5 simple beam specimens were tested, and the main test variable was a rib shape of reinforcing bars. Test data was analyzed in the viewpoint of bond strength, load-deflection relationship, and crack pattern. Test results indicated that the bond strength of high relative rib area reinforcing bars increased up to 11% compared to normal strength reinforcements. And the improved rib shape reinforcements, which were formed with high and low height rib, increased the bond strength up to 23% even though the relative rib area was same as the high relative rib area reinforcements. Serviceability performances such as deflection number of cracking, and maximum crack width were similar in all specimens, so it is safe to conclude that the improved rib shape reinforcements can be applied to the structural members.

• Investigative Magnetic Resonance Imaging
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• v.13 no.1
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• pp.54-62
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• 2009

Purpose : Craniospinal neurenteric (NE) cysts are rare developmental non-neoplastic cysts of the central nervous system with diverse MR imaging findings. The purpose of this study was to evaluate various MR imaging findings of intracranial and intraspinal NE cysts. Materials and Methods : We retrospectively reviewed the MR imaging findings of six NE cysts that were confirmed by pathology. We evaluated anatomic location, signal intensity, size and enhancement pattern of NE cysts. Results : Two intracranial lesions were located extra-axially in the cerebellopontine angle and quadrigeminal cisterns. Three spinal lesions were intraduralextramedullary cysts, located ventral to the spinal cord, but one thoracic lesion was an intramedullary cyst. The signal intensity of the cysts was hyperintense on T1-weighted images as compared with the cerebrospinal fluid (CSF) for two intracranial lesions and one cervical lesion. In addition, all intracranial lesions showed diffusion restriction. For the remaining three spinal lesions, the signal intensity was nearly the same as the signal intensity of the CSF as seen on both T1- and T2-weighted images. On contrast-enhanced studies, two intracranial cysts showed a small nodular enhancement and one thoracic spinal lesion showed rim enhancement. Conclusion : NE cysts have various locations, signal intensities, and possible focal nodular or rim enhancement. Therefore, NE cysts can be included in the differential diagnosis of various craniospinal cystic or tumorous cystic lesions.

• The Korean Journal of Mycology
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• v.22 no.1
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• pp.107-116
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• 1994

Interorder somatic hybrids were obtained by protoplast fusion between Pleurotus ostreatus in the order Agaricales and Elfvingia applanata in the order Aphyllophorales. The fusants were classified into stable heterokaryons and spontaneously segregated heterokaryons. Hyphae of all fusion products except two strains did not form clamp connections. Out of them, two clamped and three clampless fusants produced mature fruiting bodies by light-dark cycle on sawdust rice bran medium. All of these basidiocarps had clamp connections. Three fusants were analysed with the distribution of progenies and segregation of genetic characters by random spore analyses. The genetic markers were shown to segregate and recombine in the first generation of monospores isolated from basidiocarps. Phenotypes of a large number of auxotrophic progenies were not detected in the two clamped fusants. The aberration ratio of segregants indicated the gene interaction resulting from different genome structure between distantly related species. The polymerase chain reaction (PCR) was adopted for the detection of somatic hybrids nuclear DNA. Four fusants showed a positive results in three kinds of primers. The prominent reaction products are represented by new bands in primer # 87 and # 125. Out of four fusants, two somatic hybrids had non-parental mtDNA patterns when digested with EcoR1 and HindIII. Comparison of somatic hybrids, tissue culture isolates(TC) and multispore germination isolates(MS) were made using esterase isozyme analysis. It is apparent that somatic hybrids had a minor banding patterns which are quite different from those of parents.

• Journal of Navigation and Port Research
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• v.43 no.3
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• pp.172-178
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• 2019

Although the needs for providing resilient PNT information are increasing, threats due to the intentional RFI or space weather change are challenging to resolve. eLoran, which is a terrestrial navigation system that use a high-power signal is considered as a best back-up navigation system. Depending on the user's environment in the eLoran system, the user may use one of E-field or H-field antennas. H-field antenna, which has no restriction on setting stable ground and is relatively resistant to noise of general electronic equipment, is composed of two loops, and shows anisotropic gain pattern due to the different measurement at the two loops. Therefore, the H-field antenna's phase estimation value of signal varies depending on its direction even at the static environment. The error due to the direction of the signal should be eliminated if the user want to estimate the own position more precisely. In this paper, a method to compensate the error according to the geometric distribution between the H-field antenna and the transmitting station is proposed. A model was developed to compensate the directional error of H-field antenna based on the signal generated from the eLoran signal simulator. The model is then used to the survey measurement performed in the land area and verify its performance.

• Animal Bioscience
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• v.35 no.8
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• pp.1223-1234
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• 2022

Objective: The objectives of this study were to evaluate the effects of daily feed intake during the laying period on embryonic myogenic differentiation 1 (MYOD1), myogenic factor 5 (MYF5), and myogenic factor 6 (MYF6) gene expression in genetically fat and lean lines of chickens. Methods: An experiment in a 2×2 factorial design was conducted with two dietary intake levels (100% and 75% of nutrition recommendation) and two broiler chicken lines (fat and lean). Two lines of hens (n = 384 for each line) at 23th week of age were randomly divided into 4 treatments with 12 replicates of 16 birds. The experiment started at 27th week of age (5% egg rate) and ended at 54th week of age. Hatched eggs from the medium laying period were collected. Real time polymerase chain reaction analysis was used to analyse the MYOD1, MYF5, and MYF6 mRNA levels of E7, E9, E11, E13, and E15 body tissues and E17, E19, and E21 chest and thigh muscle samples. Results: The results indicated that there were significant effects of line, dietary intake, and interactions between them on MYOD1, MYF5, and MYF6 gene mRNA expression levels in embryonic tissues. Low daily feed intake did not change the expression trend of MYOD1 mRNA in either line, but changed the peak values, especially in lean line. Low daily feed intake altered the trend in MYF5 mRNA expression level in both lines and apparently delayed its onset. There was no apparent effect of low daily feed intake on the trends of MYF6 mRNA expression levels in either line, but it significantly changed the values on many embryonic days. Conclusion: Maternal nutrient restriction affects myogenesis and is manifested in the expression of embryonic MYOD1, MYF5, and MYF6 genes. Long term selection for fat deposition in broiler chickens changes the pattern and intensity of myogenesis.

• Journal of the Korean Society of Radiology
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• v.85 no.1
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• pp.147-160
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• 2024

Purpose To define an MRI scoring system for differentiating xanthogranulomatous cholecystitis (XGC) from wall-thickening type gallbladder cancer (GBC) and compare the diagnostic performance of the scoring system with the visual assessment of radiologists. Materials and Methods We retrospectively analyzed 23 and 35 patients who underwent abdominal MRI and were pathologically diagnosed with XGC and wall-thickening-type GBC after surgery, respectively. Three radiologists reviewed all MRI findings. We defined a scoring system using these MRI findings for differentiating XGC from wall-thickening type GBC and compared the area under the curve (AUC) of the scoring system with the visual assessment of radiologists. Results Nine MRI findings showed significant differences in differentiating the two diseases: diffuse gallbladder wall thickening (p < 0.001), mucosal uniformity (p = 0.002), intramural T2-high signal intensity (p < 0.001), mucosal retraction (p = 0.016), gallbladder stones (p < 0.001), T1-intermediate to high-signal intensity (p = 0.033), diffusion restriction (p = 0.005), enhancement pattern (p < 0.001), and phase of peak enhancement (p = 0.008). The MRI scoring system showed excellent diagnostic performance with an AUC of 0.972, which was significantly higher than the visual assessment of the reviewers. Conclusion The MRI scoring system showed better diagnostic performance than the visual assessment of radiologists to differentiate XGC from wall-thickening-type GBC.

• Journal of agricultural medicine and community health
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• v.24 no.1
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• pp.65-77
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• 1999

In order to estimate the utilization pattern of a rural health subcenter, and to identify the recognition for it among the farmhouse members in a suburban area, a questionnaire survey was carried out for objects of 696 population. The results observed were as follows: The annual utilization rate of rural health subcenter for a basic health service unit was 25.0 per 100 persons, and annual mean visiting times was 0.22 times. And the most frequent disease by annual health subcenter utilization illness was musculoskeletal disease(30.6%), and the next was respiratory disease(14.1%), gastrointestinal disease(13.9%) by order. Favorite reason for community health subcenter utilization were near distance from living place(49.6%), lower disease severity(18.9%) and lower medical cost(18.1%) by order. But disfavoring reasons for it were absence of specialist(20.2%), non effective treatment(19.2%) and insufficient equipment(14.7%) by order. And insufficient items about community health subcenter utilization were restriction of treatment limit(40.7%), lower reliance(22.5%) and difficulty in traffic(13.4%) by order. The results of logistic regression analysis suggested that statistically significant factors in health subcenter utilization was educational level. The desirable works for the health subcenter in a suburban area were disease control of elderly and disease preventing service. These results suggested that to increase the utilization of rural health subcenter in a suburban area and to promote the accessibility of rural residents to primary health care, there must be considered public relation about health subcenter, improvement of medical quality and change of priority about health subcenter's works.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.202-218
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• 1976

In this experiment American Summer Pairman apple was selected as test fruit in order to study the effect of sub-atmospheric pressure storage in the apple. keeping a certain pressure condition, a new sub-atmospheric pressure system was designed and constructed in which fruits were stored at $25^{\circ}C$ under two different atmospheric pressure conditions such as Normal Atmospheric Pressure (NAP) and Sub-Atmospheric Pressure (SAP). Moreover, they were divided into plots of 5% and 0% of $CO_2$, on the basis of gas composition. Under these conditions, the amount of respiration and ethylene evolution, and the changes of intercellular gas composition and organic components were investigated throughout the storage. The results obtained are as follows: (1) The intercellular gas was exhausted so rapidly by the SAP treatment that the gas equilibrium in the tissues reached within 5 minutes. (2) The amount of respiration was found to be higher in plots of NAP than SAP, and under the conditions, controlling $CO_2$ content, plots of $CO_2$ 5% were lower in the amount of respiration than $CO_2$ 0%. The climateric rise was revealed more slowly in plots of the SAP than NAP. These results indicate that the SAP treatment was an efficient method for controlling the respiration of fruits. Furthermore, these results were also realized with the results of the respiratory quotient (R.Q) and intercellular gas composition. (3) Evolution of ethylene, the ripening hormone in plant, was shown the similar tendency to the climacteric pattern of respiration; at the stage of climacteric maximum, the maximun amount of ethylene was found earlier in plots of NAP than SAP, and post climacteric stage was prolonged in the plots of the SAP compared to those of the NAP. The ethylene concentration in tissue appeared lower in plots of the SAP than NAP, which might suggest that the SAP treatment was caused to restriction of ethylene evolution. (4) Effects of the SAP treatment mentioned hitherto were proved also with the test of the external appearance such as changes of color and freshness, firmness, rotting and weight loss. (5) In the investigation of organic components, vitamin C and organic acids varied less in plots of SAP than NAP. Specially, it was remarkable that the loss of malic acid was least decreased by the SAP treatment. These effects of the SAP treatment were distinctive in the changes of the ratios of malic and citric acid to total acid, and the ratios of free sugar to free acid.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1178-1187
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• 1998

Background : Recently the incidence of tuberculosis is increasing in many countries and control of the disease is further threatened by the emergence of multi-drug resistant tuberculosis. So rapid detection of drug resistance is very important. Pyrazinamide (PZA) is a first-line chemotherapeutic agent for tuberculosis. Now in Korea, we perform PZase activity test instead of actual pyrazinamide susceptibility test for the detection of PZA resistant M. tuberculosis. Recently the pncA gene, encoding the PZase of M. tuberculosis, was completely sequenced. And it was reported that the mutation of pncA gene would be associated with PZA resistance of M. tuberculosis. Therefore we performed this study to evaluate the possibility for the rapid detection of PZA resistant M. tuberculosis using PCR-SSCP of pncA gene. Method : 44 cultured clinical isolates of M. tuberculosis, BCG Tokyo strain. BCG French strain, and one M. bovis isolate were studied. We used H37Rv as the reference strain, The PZase activity test was done at the reference laboratory of Korean Tuberculosis Institute. DNA was extracted by bead-beater method and 561 bp fragment including pncA gene was amplified by PCR. The PCR product were digested by BstB I enzyme. SSCP was done using MDE gel. Of the 44 strains of M. tuberculosis, 22 strains were PZase-positive and other 22 strains were PZase negative. Results : Of the 22 PZase positive strains, 18 strains(82%) showed the same mobility compared with that of H37Rv and 4(18%) showed different mobility. Of the 22 PZase-negative strains, 19(86%) strains showed the same mobility pattern compared with that of H37Rv and 3(14%) showed different mobility. Naturally PZA-resistant BeG-French strain, BCG-Tokyo strain, and one M. bovis isolate showed the same band pattern each other, but their mobility were different from that of H37Rv. The results of PZase activity test and PCR-SSCP of pncA of M. tuberculosis were statistically significantly correlated each other (p<0.01). Conclusion : The PCR-SSCP after BstB I restriction of pncA gene of M. tuberculosis may be a useful method for the rapid detection of PZA-resistant M. tuberculosis.