• Journal of agriculture & life science
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• v.45 no.5
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• pp.33-39
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• 2011

This study was conducted to distribution characteristic of root diameter class between natural and planted stands of one-age class in Pinus densiflora for. eracta in Gangwon. Root development presented that 0.5-2.0 mm diameter class was large part in total root number and length but 0.5-2.0 mm diameter class have a low distribution in each stand. Below 5.0 mm diameter class between natural and planted stands observed outstanding natural stand more than planted stand, but reverse over 5.0 mm diameter class. Root development depending on soil level of vertical and horizontal was presented various natural stand more than planted stand because root distribution of planted stand was concentrated low soil level in 10 cm of soil depth and 20 cm of soil horizontal layer. We can understand that the root distribution presented different between natural and planted stand, therefore this result can used as a basic information for correct of outplanting.

• Food Science of Animal Resources
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• v.43 no.6
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• pp.1170-1182
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• 2023

The aim of this study was to determine the effect of chitosan (CH)-based nanocomposite coating applications [chitosan+TiO₂ (CHT) and chitosan+TiO₂+rosmarinic acid (CHTRA)] on changes in quality attributes of rainbow trout fillets during cold storage (4℃). Fish fillets were randomly divided into four groups and subjected to treatments (CH, CHT, CHTRA, and control). After treatments, the groups were packaged under a modified atmosphere (40% CO₂+30% O₂+30% N₂) and stored at 4℃ for 18 days. During cold storage, the samples were subjected to physico-chemical and microbiological analyses. During storage, CH, CHT, and CHTRA treatments showed lower aerobic mesophilic and psychrotrophic bacteria counts than the control. However, the differences between coating treatments were not significant. The highest mean pH value was determined in the control group. As the storage time increased, the thiobarbituric acid reactive substances value increased. At the end of the storage period, no significant differences were observed between the treatments, including in the control group. The total volatile basic nitrogen (TVB-N) level in the control group was above 25 mg/100 g on day 15 of storage. However, the TVB-N level in the treatment groups was below 20 mg/100 g on day 18. It was also determined that coating application×storage period interaction had a significant effect on all color parameters (p<0.01). At the end of storage, the highest CIE L* was observed in CHTRA treatment. However, the value of this treatment did not differ from that of the CH treatment.

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.35-42
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• 2003

To use ferro copper slag as aggregate in the construction, an evaluation upon the two kinds of ferro copper slag being produced was conducted to determine the basic physical, and mechanical properties, chemical component and environmental noxiousness. As a result of experiment, it was found that two kinds of ferro copper slag satisfies the physical and mechanical properties of aggregate, prescribed in KS F 2526, and that in the result of noxious heavy metal eruption test by single bach extraction, no eruption of noxious heavy metal was detected or the eruption was far below the reference value. And mortar test was conducted by replacing sand of 25, 50, 75, 100% and the performance level was presented upon reviewing the fluidity property and variable aspects of unit weight. The increase of strength in accordance with replacement rate of sand was found to be the below than the equivalent level compared to the testing specimens that did not use ferro copper slag, but those of 25% replacement rate was above than 0%. Thus, two kinds of ferro copper slag, produced in the domestic, were found to be possessing the enough physical properties to use as concrete aggregate assuming that used with sand and in particular, it was reviewed to be advantageous in manufacturing concrete or mortar that requires weight.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.144-154
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• 2017

The riparian vegetation is one of corridor type ecosystems, an ecotone and able to improve the ecological soundness by structural and functional link. And they act as habitats, sources and sinks of species, conduits, filters and barriers. This study was carried out to develop the vegetation model for the fluctuation areas of lake reservoirs consider of hydrologic and soil environments according to the vegetation structure of the reference ecosystem. To develop the case study, 2 sites within 10degree slope of the Daecheong Lake were selected. The riparian vegetation models were built by the results of GIS analysis, remote satellite analysis, field survey results, consider of water level, flooded frequency, soil and topographic index, land cover or land use etc. 1) study area varied from FWL to -5m of NFWL, 2) slope 10% below, 3) vegetations flooded below 100days yearly are Salix koreensis, Salix chaenomeloides, Salix gracilistyla, 4)land cover type classified wildlife grassland, abandoned paddy field, cropland according to landuse (or landcover), 5)finally model was constructed as ecological landscape forest. The model designs were suggested by 2 types in Daecheong lake reservoir. The model for the riparian vegetation corridors could be the basic and useful data to improve the ecological and landscape properties.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7619-7625
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• 2015

Background: Aberrant microRNA expression has been associated with the pathogenesis of a variety of human malignancies including oral squamous cell carcinoma (SCC). In this study, we examined primary oral SCCs for the expression of 6 candidate miRNAs, of which five (miR-34a, miR-143, miR-373, miR-380-5p, and miR-504) regulate the tumor suppressor TP53 and one (miR-99a) is involved in AKT/mTOR signaling. Materials and Methods: Tumor tissues (punch biopsies) were collected from 52 oral cancer patients and as a control, 8 independent adjacent normal tissue samples were also obtained. After RNA isolation, we assessed the mature miRNA levels of the 6 selected candidates against RNU44 and RNU48 as endogenous controls, using specific TaqMan miRNA assays. Results: miR-34a, miR-99a, miR-143 and miR-380-5p were significantly down-regulated in tumors compared to controls. Moreover, high levels of miR-34a were associated with alcohol consumption while those of miR-99a and miR-143 were associated with advanced tumor size. No significant difference was observed in the levels of miR-504 between the tumors and controls whereas miR-373 was below the detection level in all but two tumor samples. Conclusions: Low levels of miR-380-5p and miR-504 that directly target the 3'UTR of TP53 suggest that p53 may not be repressed by these two miRNAs in OSCC. On the other hand, low levels of miR-34a or miR-143 may relieve MDM4 and SIRT1 or MDM2 respectively, which will sequester p53 indicating an indirect mode of p53 suppression in oral tumors.

• Journal of Technologic Dentistry
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• v.30 no.1
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• pp.121-130
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• 2008

The purpose of this research project is to assess students' stress during clinical rotations and to suggest strategies for enhancing professional skills as well as the quality of clinical rotations among the students of dental technology. The participants included 200 sophomores and juniors from dental laboratory college located in Daegu and Jeju. Data was collected December 7, 2007, and March 7, 2008, by survey samplings. A total of 185 completed surveys were obtained and analyzed for this study. Findings from the study are summarized below. When age and stress were compared, it was found that younger students had higher levels of stress related to their environment, role, and activities. Regarding grade level and stress, students in lower levels were slightly (p<.01) more likely to have stress (Sophomore =2.91, junior =2.49). When the stress level was compared with students' satisfaction with their major, the less students were satisfied, the higher their level of stress was. The study found a slight (p<.05) difference between groups [satisfaction group (M=2.44), group in between satisfaction and dissatisfaction (M=2.58), and dissatisfaction (M=2.82)) in the relationship between satisfaction with the major and overall stress. Again, it appears that stress levels increase as satisfaction with the chosen major decreases. Third, the intensity of stress was affected by the environment in which students practiced, classmate relationships, roles, goals and values, and activities, and areas of performance. It showed that the groups unsatisfied and in-between with the quality of practice have more intensified stress than the group with satisfaction. The study showed a slight (p<.01) difference amongst groups [(satisfaction group (M=2.17), group in between satisfaction and dissatisfaction (M=2.68), and dissatisfaction (M=2.96)) in the relationship between satisfaction with the quality of the clinical rotation and overall stress. It appeared that higher levels of stress were seen with lower satisfaction with the major. Overall, students' level of stress was correlated with age and grade level, level of satisfaction in the major and the quality of the clinical rotation. Furthermore, schools need to focus on improving the environment where students practice, classmate relationships, roles, goals and values, and activities, and areas of performance. Dental laboratory colleges should concentrate on the basic case with the quality of clinical rotation and the chosen major. More skillful teaching and properly assigned clinical rotations and classes, along with a strong practical knowledge base applicable to clinical rotations will be needed in order to address these sources of dissatisfaction.

• Journal of the Korean Chemical Society
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• v.66 no.2
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• pp.136-149
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• 2022

Chemistry focuses on explaining macroscopic phenomena at the microscopic level with particles, such as atoms or molecules. Explanation using particles are bound to be considered as abstract by students, because it was dealing with invisible objects. For that reason, the science national curriculum presented to middle school students the explanation of the units related to the composition of matter. Therefore, understanding about the composition of matter in middle school students becomes an important basis for learning of chemistry, and it is necessary to investigate their understanding about composition of matter. In this study, students' understanding about 'composition of matter' region, which is first presented to middle school students, was confirmed at an overall level. In this line, this study analyzed the results of the items in the composition of matter region, and analyzed items were used in the National Assessment of Educational Achievement (NAEA) from 2015 to 2019. We analyzed the 9 items presented in the NAEA according to the response rate of options and response rate distribution curve, and explained the characteristics of understanding derived by each achievement level were examined. According to the analyzed results by dividing the conceptions about elements, atoms, and ions, students above the proficient achievement-level had scientific conceptions overall, but students below the basic achievement-level had inconsistent or naive conceptions. Based on the results for each item, this study discussed some implications to be considered or to be improved on teaching-learning for 'composition of matter'.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.2
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• pp.87-94
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• 2005

Purpose : Heavy metal use when producing the block from the workshop. At this time, production of heavy metal dust and fume gives risk in human. This like heavy metal to improve seriousness through measurement and analysis. And by the quest in solution is purpose of this thesis. Materials and Methods : Organization is Inductively Coupled Plasma Atomic Emission Spectrometer, and the object is Deajeon city 4 workshops in university hospital radiation oncology (Bismuth, Lead, Tin and cadmium). Method is the ppb the pumping it does at unit, comparison analysis. And the Calculation heavy metal standard level in air through heavy metal standard level in body and blood, so Heavy metal temporary standard set. Results : Subterranean existence room air quality the administration laws appointed Lead and Cadmium's exposure recommend that it is $3{\mu}g/m^3\;and\;2{\mu}g/m^3$. And Bismuth and Tin decides $7{\mu}g/m^3\;and\;6{\mu}g/m^3$ through standard level in air heavy metal and standard level in body and blood. Heavy metal measurement level of workshops in 4 university hospital Daejeon city compares with work existence and nonexistence. On work nonexistence almost measurement level is below the recommend level. But work existence case express high level. Also consequently in composition ratio of the block is continuous with the detection ratio. Conclusion : Worker's heavy metal contamination imbrued serious for solution founds basic part. In hospital may operation on local air exhauster and periodical efficiency check, protector offer, et al. And worker have a correct understanding part of heavy metal contamination, and have continuous interest, health control. Finally, learned society sphere administer to establishment standard level and periodical measurement. And it founds basic solution plan of periodical special health checkup.

• Parasites, Hosts and Diseases
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• v.23 no.2
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• pp.241-246
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• 1985

The epidemiological status of ascariasis was analyzed in 8 rural villages in Korea, through observation of its epidemiological parameters such as prevalence, worm burden and basic reproductive rate. Total 978 inhabitants were subjected to stool examination and recovery of worms after chemotherapy with pyrantel pamoate. The results were as follows: 1. The worm positive rate in each village was 16.5~79.5%, while the egg positive rate was 9~18% lower, 3.3~66.7%. The average worm burden (among all inhabitants) ranged from O. 21 to 8. 44 by villages and the frequency of cases with each worm burden showed negative binomial distributions with 'k' values of O. 38-0. 54. 2. The prevalence rates (worm) in each village was almost identical with the theoretical ones from Anderson and May's equation; $p=1-(1+M^*/k)^{-k}$, where 'p' is worm prevalence and '$M^*$' equilibrium average worm burden. The basic reproductive rate 'R' was calculated from 1.03 to 2.11. lt is suggested that, although 'R' in lower endemic areas is approaching to the breakpoint of reinfection (R=1), control programs of ascariasis in Korea should be continued until it becomes below the level nationwidely.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.85-92
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• 2019

This study was a descriptive study conducted to identify factors that had an influence on clinical competency of core basic nursing skills(CBNS) during the clinical practice in nursing students. Data were collected from 3rd and 4th grade 190 nursing students in G city using self-report questionnaire, and analyzed using descriptive statistics, the t-test, one way ANOVA, multiple regression with SPSS 23.0 program. This study found that the number of experience CBNS below 5 was 51.1%, and the number of observation CBNS over 11 was 78.4%. Clinical competency according to general characteristics, clinical practice satisfaction and the level of CBNS experience increased with male, increase age and grade, and major subject satisfaction and clinical practice satisfaction, especially, as the number of experience CBNS increased, clinical competency increased(p<0.001). But clinical competency did not differ according to the number of observation CBNS(p=0.463). The factors affecting the clinical competency of nursing students were age, grade, clinical practice satisfaction and the number of experience CBNS. Therefore, it is important to increase the opportunity to directly experience the various CBNS in clinical practice of nursing students in the nursing education curriculum, and it is necessary to find ways to actively use simulation education.