• Journal of Environmental Impact Assessment
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• v.30 no.1
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• pp.13-23
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• 2021

In this study, we performed a Random Walker analysis to predict the Major Movement Paths of otters. The scope of the research was a simulation analysis with a radius of 7.5 km set as the final range centered on the Ansim-wetland in Daegu City, and a field survey was used to verify the model. The number of virtual otters was set to 1,000, the number of moving steps was set to 1,000 steps per grid, and simulations were performed on a total of 841 grids. As a result of the analysis, an average of 147.6 objects arrived at the boundary point under the condition of an interval of 50 m. As a result of the simulation verification, 8 points (13.1%) were found in the area where the movement probability was very high, and 9 points (14.8%) were found in the area where the movement probability was high. On the other hand, in areas with low movement paths probabilities, there were 8 points (13.1%) in low areas and 4 points (6.6%) in very low areas. Simulation verification results In areas with high otter values, the actual otter format probability was particularly high. In addition, as a result of investigating the correlation with the otter appearance point according to the unit area of the evaluation star of the movement probability, it seems that 6.8 traces were found per unit area in the area where the movement probability is the highest. In areas where the probability of movement is low, analysis was performed at 0.1 points. On the side where otters use the major movement paths of the river area, the normal level was exceeded, and as a result, in the area, 23 (63.9%), many form traces were found, along the major movement paths of the simulation. It turned out that the actual otter inhabits. The EN-Simulator analysis can predict how spatial properties affect the likelihood of major movement paths selection, and the analytical values are used to utilize additional habitats within the major movement paths. It is judged that it can be used as basic data such as to grasp the danger area of road kill in advance and prevent it.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.227-235
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• 2020

This study was conducted to investigate the growth characteristics of the shoot and roots and to analyse the morphological characteristics of roots of waterlogging resistant and susceptible maize inbred lines. Six maize inbred lines were treated with waterlogging for 10 days at V3, and the degree of leaf senescence was evaluated for waterlogging resistance. As a result of waterlogging resistance evaluation, KS85 was the most damaged inbred line with 3.33 senescence leaves and 5.54 degree, and KS141 was the least damaged inbred line with 1.33 senescence leaves and 3 degree. At 20 days after treatment, the effect of waterlogging stress on the shoot dry matter accumulation of KS85 and KS141 were decreased by 86.1% and 77.0%, respectively, compared to the control. Similarly, root dry matter accumulation of KS85 and KS141 were decreased by 77.6% and 65.0%. As a result of SEM photographs of the nodal roots of the two maize inbred lines, the thickness of cortex of KS141 was thicker than that of KS85, and the distortion of the cortex was observed in KS85 at 20 days after waterlogging. It was concluded that the thickness of cortex was related to maize waterlogging resistance.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.383-391
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• 2020

The vertical distribution and dispersion of the two-spotted spider mite, Tetranychus urticae and its predator, Phytoseiulus persimilis, were investigated within and between green pepper plants. We also tested the effect of an artificial bridge with threads on dispersal of P. persimilis between the plants. The extent of spread of T. urticae depended on its infested density and location. When 10 adults of T. urticae were inoculated on upper leaf, they stayed on the upper leaf until 5 days after inoculation. However, when 100 adults were inoculated on an upper leaf, they dispersed to the lower leaf within a day. In condition that 10 adults of T. urticae were inoculated on the lower leaf, they started to move toward upward within a day. In the absence of T. urticae, P. persimilis tended to move to the leaves where T. urticae was present when both T. urticae and P. persimilis were inoculated together within a plant. An artificial bridge with threads between two plants was helpful to disperse P. persimilis to neighboring plants. Therefore, it would be expected that the dispersal of P. persimilis can be promoted by supplying the artificial bridges among plants and by narrowing the distances between plants.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.374-390
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• 2021

Growth and yield of field vegetable crops would be affected by climate conditions, which cause a relatively large fluctuation in crop production and consumer price over years. The yield prediction system for these crops would support decision-making on policies to manage supply and demands. The objectives of this study were to compile literatures related to onion and garlic and to perform data-mining analysis, which would shed lights on the development of crop models for these major field vegetable crops in Korea. The literatures on crop growth and yield were collected from the databases operated by Research Information Sharing Service, National Science & Technology Information Service and SCOPUS. The keywords were chosen to retrieve research outcomes related to crop growth and yield of onion and garlic. These literatures were analyzed using text mining approaches including word cloud and semantic networks. It was found that the number of publications was considerably less for the field vegetable crops compared with rice. Still, specific patterns between previous research outcomes were identified using the text mining methods. For example, climate change and remote sensing were major topics of interest for growth and yield of onion and garlic. The impact of temperature and irrigation on crop growth was also assessed in the previous studies. It was also found that yield of onion and garlic would be affected by both environment and crop management conditions including sowing time, variety, seed treatment method, irrigation interval, fertilization amount and fertilizer composition. For meteorological conditions, temperature, precipitation, solar radiation and humidity were found to be the major factors in the literatures. These indicate that crop models need to take into account both environmental and crop management practices for reliable prediction of crop yield.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.493-503
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• 2021

The study was designed to analyze raw and auxiliary materials of Korean traditional cookies such as Yugwa and Gangjeong, equipment and tools, personal hygiene of workers and microbial contamination of materials by each manufacturing process. In addition, it looked at washing method for reducing microorganisms at the site and reduction effect of microorganisms by frequency in the manufacturing processes of Yugwa. In the process of producing Korean traditional cookies, the level of total aerobic bacteria (TAB) in popped rice was 1.2 Log CFU/g and the level of TAB in finished products increased to 3.7 Log CFU/g. In the process of producing Yugwa, the level of TAB increased to a maximum of 6.5 Log CFU/g in the soaking process but decreased to 1.3 Log CFU/g in the frying process. However, the level of TAB increased again to 1.3 Log CFU/g in finished products that proves its recontamination. It is estimated that he manufacturing process causes cross-contamination that comes from the work tools, equipment or workers. In particular, the spatula, one of the work tools, was found to have 4.4 Log CFU/g of aerobic bacteria and 4.2 Log CFU/g of colon bacillus that show they are highly contaminated. In the soaking process of Yugwa that lasts seven days, the level of TAB was a maximum of 10 Log CFU/g and the level of total colon bacillus was 6.8 Log CFU/g. When compared with washing methods, using hands and tools or running water, it is confirmed that the level of both TAB and total colon bacillus decreased to 5.0 Log CFU/g and 2.8 Log CFU/g respectively when hands were washed with running water 10 times. The above result shows that it's required for workers to wash their hands as well as wash and disinfect work tools and equipment in the process of producing Korean traditional cookies at small-scale companies. In addition, to reduce the level of microbial contamination in finished products, workers are required to apply their reduction method at the site.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.143-151
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• 2022

Purpose. The purpose of this study was to evaluate the performance efficiency of two different drill combinations according to the heat generated and drilling time. Materials and methods. In this study, cow ribs were used as research materials. To test the specimen, cow bones were rid of fascia and muscles, and a temperature sensor was mounted around the drilling area. The experimental group was divided into a group using a guide drill and a group using a Lindmann drill according to the drill used before the initial drilling. The drilling sequence of the guide drilling group is as follows; guide drill (ø 2.25), initial drill (ø 2.25), twist drill (ø 2.80), and twist drill (ø 3.20). The drilling sequence of the Lindmann drilling group is as follows; Lindmann drill (ø 2.10), initial drill (ø 2.25), twist drill (ø 2.80), and twist drill (ø 3.20). The temperature was measured after drilling. For statistical analysis, the difference between the groups was analyzed using the Mann-Whitney U test and the Friedman test was used (α = .05). Results. The average performance efficiency for each specimen of guide drilling group ranged from 0.3861 to 1.1385 mm³/s and that of Lindmann drilling group ranged from 0.1700 to 0.4199 mm³/s. The two drill combinations contained a guide drill and Lindmann drill as their first drills. The combination using the guide drill demonstrated excellent performance efficiency when calculated using the drilling time (P < .001). Conclusion. Since the guide drill group showed better performance efficiency than the Lindmann drill group, the use of the guide drill was more suitable for the primary drilling process.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.218-223
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• 2022

This study, conducted during 2018-2021 in Gangseo, Seoul, monitored residual pesticides in 14 types of fresh-cut produce, including lettuce, tomato, and celery, in wholesale market and supermarkets. A total of 589 cases (2.9%) were inspected; 17 cases (2.9%) were detected within the criteria, and 2 cases (0.3%) exceeded the maximum residual limit (MRL). When assessing the distribution stage of the pesticide violation, there were two violations in the wholesale market (before distribution), which differed from the supermarkets (during distribution). The detected pesticides, mainly insecticides and fungicides, appeared in the order of flubendiamide, flufenoxuron, and diazinon. A violation rate of 0.3% was found for wholesale market, which is collection area dedicated to fresh-cut produce, and this was lower than that for general agricultural products (1.4-2.5%). Since fresh-cut produce are consumed immediately after simple processing, residual pesticides significantly affect the human body; therefore, continuous monitoring of pesticide residues is required.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.481-487
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• 2021

The purpose of this study was to provide safety management information by analyzing the survival and growth-related properties of foodborne pathogens from Romaine lettuce. After cultivating E. coli O157:H7 for 72 h on Romain lettuce via spray inoculation, the bacteria population increased by 2.0 log CFU/g from the initial population, confirming the possibility of survival and multiplication of the pathogen thereon. The study also revealed that there is no significant difference in the cultivation of E.coli O157:H7 after 72 h from inoculation on damaged and undamaged lettuce leaves. As a result of investigating distribution of E.coli O157:H7 on damaged lettuce leaves, it was found that the bacteria is unlikely to adhere on the smooth surface of undamaged leaves and, thus, results in a low population density, whereas the bacteria cluster on the rough surface of damaged leaves and easily enter through the damaged tissues. Furthermore, after 24 h of cultivation of the pathogenic microbe in the extract with concentrations of 10-100%, utilization of the lettuce extract by the pathogen was found to be 8.9 log CFU/mL E. coli O157:H7, 8.6 log CFU/mL L. monocytogenes, and 8.8 log CFU/mL P. carotovorum. The increase in the population of both the pathogenic microbe and foodborne pathogen reached over 4 log CFU/mL, implying the microbe can utilize the lettuce extract as a source of nutrition. Compared to the initial inoculation concentration in 0.1% lettuce extract, the final concentration has increased up to 2.7 log CFU/mL E. coli O157:H7, 1.3 log CFU/mL L. monocytogenes, and 2.9 log CFU/mL P. carotovorum. Accordingly, the study confirms that the minimal growth concentration of the pathogenic microbe is lower than 0.1% and that the pathogen possibly survive and multiply inside the lettuce leaves given the lettuce extract with concentration of 0.1% is consistently supplied through the damaged tissues.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.2
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• pp.79-88
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• 2022

This study was conducted to evaluate the productivity of whole crop silage wheat utilizing the paddy fields during a couple of years from 2019 to 2021 in Suwon, Korea. This investigation was used the two maturity types of wheat cultivar 'Cheongwoo' (early) and 'Taeu' (late). The heading date of 2^nd year (Oct. 2020 to May. 2021) cultivation was delayed about 11 to 13 days by more than 1^st year (Oct. 2019 to May. 2020). The growth characteristics were shown that the plant height was increased in 2^nd cultivation, while the number of culms and the panicle part ratio were decreased. Moreover, the nutritive value of 'Cheongwoo' and 'Taeu' were also decreased in 2^nd cultivation. These changes have thought to a difference of the precipitation by cultivation years. Because, the precipitation during the period from the end of winter dormancy to the harvesting stage in 2^nd (337 mm) cultivation was more about twice than 1st (169.3 mm) cultivation. However, the dry matter yield of 'Cheongwoo' was not shown a statistical difference by cultivation years, while 'Taeu' was shown to decrease tendency. The total dry matter yield regardless of the cultivation years were higher in 'Cheongwoo' than 'Taeu', and especially 'Cheongwoo' was more 3 tons per hectare (15.3 t/ha) than 'Taeu' (12.6 t/ha) at 2^nd cultivation (p<0.01). The trend of dry weight in 'Cheongwoo', early mature type, showed a relatively high ratio of dry matter (p<0.05) was considered that due to a high panicle ratio by a fast heading and an adequate weight of panicles by a sufficient maturing. In conclusion, selecting the early maturity cultivars could achieve a higher and more stable total dry matter yield considering the cropping system in the central region. Furthermore, it also has the advantage of being able to double-cropping system with forage rice, which has considered the maximum whole-crop forage production year-round. These results suggest that the 'Cheongwoo' be optimum cultivar to produce the year-round forage on paddy fields in the central region.

• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.391-397
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• 2021

Purpose: Tranexamic acid (TXA) can reduce perioperative blood loss and the frequency of blood transfusions in lower extremity surgery. On the other hand, the effects of TXA on reverse total shoulder arthroplasty (rTSA) remain undetermined. This study evaluated the efficacy of TXA on perioperative blood loss, transfusion requirements, and the change in the hemotologic index. Materials and Methods: This study evaluated patients who underwent rTSA from September 2009 to July 2020. The patients were classified into two groups. The TXA group were administered TXA intravenously and topical TXA during surgery. The non-TXA group was not administered TXA. The quantity of hemovac drainage, which represented the postoperative blood loss, transfusion requirements, and postoperative change in hemoglobin and hematocrit level, were recorded. Results: The TXA and non-TXA groups consisted of 93 and 84 patients, respectively. The preoperative demographics showed no significant differences in age (72.0±7.0 vs. 71.5±5.8, p=0.656), sex (male:female, 28:65 vs. 23:61, p=0.689) and the prevalence of hypertension and diabetes (hypertension:diabetes:both, 36:3:13 vs. 32:3:8, p=0.806) between the two groups. There were significant differences in the requirements of transfusion (0 vs. 9, p=0.001), hemovac drainage at the 1^st (98.8±61.2 ml vs. 162.7±98.8 ml, p<0.001), the 2^nd postoperative day (73.8±48.4 ml vs. 91.5±54.5 ml, p=0.024), hemoglobin level at the 1^st (11.7±1.2 g/dl vs. 11.2±1.4 g/dl, p=0.048), 3^rd (10.9±1.2 g/dl vs. 10.2±1.2 g/dl, p<0.001), and 6^th (11.2±1.3 g/dl vs. 10.7±1.3 g/dl, p=0.020) postoperative day, and the hematocrit level at the 1^st (35.0%±3.6% vs. 32.5%±3.8%, p=0.001), 3^rd (32.3%±5.0% vs. 29.8%±3.6%, p<0.001), and 6^th (33.5%±3.8% vs. 31.5%±3.7%, p<0.001) postoperative day between the two groups. Conclusion: Intravenous and topical intra-articular TXA can reduce the transfusion requirement and blood loss in rTSA.