• Journal of agricultural medicine and community health
• /
• v.47 no.2
• /
• pp.109-120
• /
• 2022

Objectives: The purpose of this study was to identify the effectiveness of COVID-19 vaccinations on deaths of the COVID-19 cases in some elderly long-term care facilities (LTCF) in Gwangju Metropolitan City. Methods: The study subjects were 659 COVID-19 cases in residents of 7 elderly LTCF, Gwangju, from 21 Dec. 2021 to 28 Jan. 2022. The used variables were confirmed dates for COVID-19, demographic characteristics, co-morbidities, presentation of symptoms, death and vaccination related characteristics including type of vaccine, doses and dates. Vaccination status were classified as not vaccinated, partially and fully vaccinated. The associations of vaccination status and deaths of COVID-19 cases were tested by chi-square test and multiple logistic regression analysis. Results: The rates of not vaccinated, partially vaccinated and fully vaccinated were 19.4%, 10.2% and 70.4%, respectively. The mortality rate of the cases was 6.4%. The death rate by vaccination status was 16.4% in not vaccinated, 15.4% in partially vaccinated and 2.6% in fully vaccinated, showing a statistically significant difference. The adjusted odds ratios (ORs) (95% confidence intervals, CIs) of death compared to fully vaccinated were 7.64 (3.87-16.34) in non-vaccinated, and 6.97 (3.44-14.14) in partially vaccinated. Conclusions: COVID-19 vaccination seems to work effectively in preventing deaths of COVID-19 cases of elderly LTCF residents. This finding support that fully vaccinations in high risk group such as elderly LTCF residents is very important for one of strategies of COVID-19 management.

• Resources Recycling
• /
• v.32 no.3
• /
• pp.3-8
• /
• 2023

This study discussed production, demand, and future prospects of rubidium, which is an alkali group metal that is highly reactive to various media and requires carefulness in handling, but no significant environmental hazard of rubidium has been reported yet. Rubidium is used in various fields such as optoelectronic equipment, biomedical, and chemical industries. Because of difficulty in production as well as limited demand, the transaction price of rubidium is relatively high, but its detail information such as market status and potential growth is uncertain. However, if the mass production of versatile ultra-high-performance equipment such as quantum computers and the necessity of rubidium use in the equipment are confirmed, there is a possibility that the rubidium market will expand in the future. Rubidium is often found together with lithium, beryllium, and cesium, and may be present in granite containing minerals such as lepidolite and pollucite, as well as in seawater and industrial waste. Several technologies such as acid leaching, roasting, solvent extraction, and adsorption are used to recover rubidium. The maximum recovery efficiency of the rubidium from the sources and the processing above is generally high, but, in many practices, rubidium is not the main recovery target, and therefore the actual recovery effects should depend on presence of other valuable components or impurities, together with recovery costs, energy consumption, environmental issues, etc. In conclusion, although the current production and consumption of rubidium are limited, with consideration of the possible market fluctuations according to the emergence of large-scale demand sources, etc., further investigations by related institutions should be necessary.

• Journal of the Korean Society of Radiology
• /
• v.17 no.7
• /
• pp.1139-1147
• /
• 2023

The purpose of this paper is to present and evaluate the performance of a method for controlling the dose for optimal image acquisition while minimizing patient exposure by applying a small-sized Photomultiplier(SiPM) sensor inside a portable detector. Portable detectors have the advantage of being able to quickly access the patient's location for rapid diagnosis, but this mobility comes with the challenge of dose control. This paper presents a method to identify the dose that can have the DQE and optimal image quality of the detector through image evaluation based on IEC62220-1-1, an international standard for X-ray imaging devices, and to identify the optimal dose by matching the ADU of the image and the output of the SiPM Sensor. The Skull AP image was acquired by implementing the detector manufacturer's reference dose. The optimal dose was 342.8 µGy, and the optimal controlled dose was 148.3 µGy, which is 57 % of the manufacturer's reference dose. The Chest AP image was 81.9 µGy and the optimal controlled dose was 27.9 µGy, which is a high dose reduction effect of 66 %. In addition, the two images were analyzed by five radiologists and found to have no clinically significant difference in anatomical delineation.

• Journal of Life Science
• /
• v.33 no.12
• /
• pp.1025-1035
• /
• 2023

In this study, we analyzed SNPs that appear between Korean and Chinese Scapharca subcrenata using the nucleotide sequence data of S. subcrenata analyzed by genotyping by sequencing (GBS). To distinguish the country of origin for S. subcrenata in Korean and Chinese, we developed a primer set as single nucleotide polymorphism (SNP) markers for quantitative real-time PCR (qPCR) analysis and validated by sequencing SNPs. A total of 180 samples of S. subcrenata were analyzed by genotyping by sequencing, and 15 candidate SNPs were selected. SNP marker selection for country of origin were identified through real-time qPCR. Insertion 1 and SNP 21 markers showed the most distinct separation between the sequence types as well as the country of origin through qPCR, with the observed amplification patterns matching the expected outcomes.. Additionally, in a blind test conducted by mixing samples of S. subcrenata at random, Insertion 1 showed 74% accuracy, 52% sensitivity, and 96% specificity, and SNP 21 showed 86% accuracy, 79% sensitivity, and 93% specificity. Therefore, the two SNP markers developed are expected to be useful in verifying the authenticity of the country of origin of S. subcrenata when used independently or in combination.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.50 no.3
• /
• pp.289-299
• /
• 2024

Chrysanthemum lucidum (C. lucidum), a perennial herb in the Asteraceae family, is an endemic species found only on Ulleung island in Gyeongsangbuk-do, South Korea. Previous studies have reported that the extract of C. lucidum exhibits excellent antioxidant activity due to its high polyphenol and flavonoid content. However, the anti-aging effects of C. lucidum extract, such as wrinkle improvement and cell regeneration, are not well known, and there has been no research on the activity of C. lucidum-derived extracellular vesicles (ClDEVs). Therefore, this study aimed to verify the anti-aging effects of ClDEVs through in vitro and clinical analyses. In cell experiments, ClDEVs promoted cell regeneration, increased the expression of COL1A1, a gene involved in collagen synthesis, and enhanced the expression of FLG and LOR, a biomarker related to skin barrier improvement. Additionally, ClDEVs suppressed the expression of aging-related biomarkers, such as the CDKN2A (encodes p16) and TP53 (encodes p53) genes, in cells induced to age. In a human clinical trial, after using a cosmetic product containing ClDEVs for 4 weeks, significant improvement in wrinkles around the eyes and nasolabial folds was observed. In conclusion, ClDEVs have demonstrated high potential as a bio-cosmetic ingredient for wrinkle improvement and anti-aging.

• Journal of Life Science
• /
• v.19 no.4
• /
• pp.532-537
• /
• 2009

Previous studies reported that the N-methyl-D-aspartate (NMDA) receptor is related to alcohol dependence in terms of developing withdrawal or tolerance, however, it is controversial whether NMDA receptor antagonists are effective in preventing relapse in alcohol-dependent patients or not. The purpose of this study was to investigate the effect of memantine, an NMDA receptor antagonist, on alcohol intake in C57BL/6 mice, which prefer drinking hereditarily. Using limited access procedures in C57BL/6 mice in the state of alcohol dependence, vehicle, naltrexone 1.0 mg/kg or, memantine 5, 25, or 50 mg/kg i.p. was administered respectively for twelve days. Medication effects on 2-hours alcohol, 22-hour water, and 24-hour food intake and body weight were studied. Using repeated measure ANOVA, the naltrexone 1 mg/kg, memantine 5, 25, or 50 mg/kg, and vehicle groups showed significant medication by day interaction (naltrexone, df=4, F=11.827, p<0.01, memantine 5 mg/kg, df=4, F=7.999, p<0.01; memantine 25 mg/kg, df=4, F=6.199, p<0.05; memantine 50 mg/kg, df=4, F=10.522, p<0.01) in 2-hour alcohol intake. In 3 memantine groups, there was no significant medication by day interaction with the vehicle group in 22-hour water intake, 24-hour food intake, or body weight. The naltrexone and vehicle groups showed significant medication by day interaction in body weight, but not in 22-hour water or 24-hour food intake. From these results, it is suggested that memantine treatment can affect alcohol intake in mice. Therefore, it is possible that a pure NMDA receptor antagonist is effective in preventing relapse in alcohol-dependent patients.

• Journal of Environmental Impact Assessment
• /
• v.26 no.2
• /
• pp.160-170
• /
• 2017

The purpose of this study is to perform clustering of the habitat types and to identify the characteristics of species in the habitat types using mammal data (70,562) of the 3rd National Ecosystem Survey conducted from 2006 to 2012. The 15 habitat types recorded in the field-paper of the 3rd National ecosystem survey were reclassified, which was followed by the statistical analysis of mammal habitat types. In the habitat types cluster analysis, non-hierarchical cluster analysis (k-means cluster analysis), hierarchical cluster analysis, and non-metric multidimensional scaling method were applied to 14 habitat types recorded more than 30 times. A total of 7 Orders, 16 Families, and 39 Species of mammals were identified in the 3rd National Ecosystem Survey collected nationwide. When 11 clusters were classified by habitat types, the simple structure index was the highest (ssi = 0.07). As a result of the similarities and hierarchies between habitat types suggested by the hierarchical clustering analysis, the residential areas were the most different habitat types for mammals; the next following type was a cluster together with rivers and coasts. The results of the non-metric multidimensional scaling analysis demonstrated that both Mus musculus and Rattus norvegicus restrictively appeared in a residential area, which is the most discriminating habitat type. Lutra lutra restrictively appeared in coastal and river areas. In summary, according to our results, the mammalian habitat can be divided into the following four types: (1) the forest type (using forest as the main habitat and migration route); (2) the river type (using water as the main habitat); (3) the residence habitat (living near residential area); and (4) the lowland type (consuming grain or seeds as the main feeding resource).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.33 no.6
• /
• pp.529-532
• /
• 2000

To establish a food safety of dried layer, heat treatment effect on the bacterial density of dried layers was investigated. And a modified process developing experiment for dried layer products using closing type drying oven was carried out. tittle bacterial density difference on the dried layer products were found before and after heat treatment at $90^{\circ}C$ for 6 hrs called Hwaip treatment having been used for long term storage. Direct or indirect heat treatment of dried lavers using gas burner and frying pan reduced about 1 to 3 log cycle of viable cell count from $10^8\;CFU/g\;to\;10^5\;CFU/g$. Heat treatment by direct surface contact type cooking machine being used in the market place for cooked dried layer products could reduce the viable cell count on the layer product from $2.2{\times}10^5{\~}5.2{\times}10^7\;CFU/g\;to\;7.0{\times}10^2{\~}5.0{\times}10^5\;CFU/g$, Ultraviolet irradiation (20 W, 30 cm) to one or both side of the dried laver products reduced the viable cell count from $2.2{\times}10^6\;CFU/g\;to\;8.0{\times}10^5\;CFU/g\;and\;2.0{\times}10^5\;CFU/g$, respectively. The viable cell count of the dried layer products produced by modified process using a closing type dryer was about $10^3\;CFU/g$ and lower 3 log cycle than that in the products collected in market place and made by open type dryer.

• Journal of Conservation Science
• /
• v.32 no.4
• /
• pp.579-588
• /
• 2016

This study analyzed nonmetallic inclusions in iron swords with a ring pommel excavated in the Ipbuk-dong, Suwon. Scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS) was used to estimate the iron-making temperature, and we compared the oxide with $SiO_2$ to investigate the heat-treatment technology in the production of iron swords with a ring pommel by investigating the artificial insertion of a slag former and the metallurgical structure. From the wustite observed in most of the specimens, it is judged that these swords were produced by heating and forging iron smelted at a low temperature using the solid reduction method. In addition, judging from the partial presence of $P_2O_5$, it is assumed that they were smelted directly with natural ore, not calcined. From the ratios of $CaO/SiO_2$ and $TiO_2/SiO_2$, it is judged that the raw material for iron-making was iron ore and that a calcareous slag former was not artificially inserted. The structure of the blade part on the front end was pure iron. From the high carbon content of the blade part on the ring pommel and the formation of a martensitic structure and pearlite colony, it is judged that they were tempered after carburizing and that the back, handle part, and ring pommel were unintentionally carburized. Judging from the structure of these specimens, it was noted that they were produced by applying artificial partial heat-treatment technology. This study attempted to present a more scientific analysis by using the method of interpretation through component analysis of nonmetallic inclusions appearing in one relic by the ratio of the oxide divided by $SiO_2$. It is judged that reinterpreting the arguments by the results of the existing analysis and research in this way can obtain different interpretations.

• Journal of Korean Home Economics Education Association
• /
• v.20 no.1
• /
• pp.137-152
• /
• 2008

This study examined the organization and operation of home economics curriculum of specialized middle school in the form of regular school among alternative schools and analyzed the perceptions of teachers and students about home economics class. Interviews were conducted with teachers of 6 specialized schools in order to determine the operations and teachers' perceptions of home economics education. Students' perceptions for home economics class were gathered through surveys with students from the 3 (of the original 6) schools that authorized the questionnaire survey. The final analysis utilized 205 student responses. Survey data were analyzed using the SPSS program. The results of the research were as follows: First, home economics education within specialized middle schools was mostly conducted according to the form of the technology-home economics curriculum, which is the national common basic curriculum. Compared to the 7th national curriculum, the class of technology-home economics curriculum in 4 schools occurred 1 hour less each week. Each school incorporated various specialized curricula related to home economics. Second, as for the operation of home economics education in specialized schools, most home economics classes were conducted by teachers who had majored (or minored) in home economics. Moreover, all but 1 school, which used self-made materials, used the national textbook and dealt with the entire content of the textbook. For teaching-learning methods and instructional media, various means were utilized. For evaluation methods, most schools based grades on paper-and-pencil tests(50-60%) and performance tests(40-50%). Third, among teachers' perceptions of home economics education, the meaning of home economics education was focused on practical help and the pursuit of home happiness; the purpose was to realize the happiness of students and their homes by applying these to actual living, and increase students' ability to see the world. In regards to difficulties in educational operations, most pointed out poor conditions of practice rooms. As for differences from general schools, most teachers mentioned the active communication with students. Fourth, through the home economics class, it was found that students perceived the goal of technology-home economics curricula as lower than average. Among students' perceptions about home economics class, most were negative. Perceptions about goal of technology-home economics curricula and home economics class also showed meaningful differences according to each school. Students of the school, which had more home economics class hours and specialized curricula related to home economics, perceived more positively. Also, students who were more satisfied with school and learned from a teacher who majored in home economics tended to perceive home economics class more positively.