• Journal of the Korean Society of Radiology
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• v.13 no.5
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• pp.757-763
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• 2019

Recently, Following the recent development of flat panel detector with wide dynamic ranges, increasing numbers of healthcare providers have begun to use digital radiography. As a result, filter thickness standards should be reestablished, as current clinical practice requires the use of thicknesses recommended by the National Council on Radiation Protection and Measurements, which are based on information, acquired using conventional analog systems. Here we investigated the possibility of minimizing dose creep and optimizing patient dose using Al filters in digital radiography. The use of thicker Al filters resulted in a maximum 19.3% reduction in the entrance skin exposure dose when medical images with similar sharpness values were compared. However, resolution, which is a critical factor in imaging, had a significant change of 1.01 lp/mm. This change in resolution is thought to be due to the increased amount of scattered rays generated from the object due to the X-ray beam hardening effect. The increase in the number of scattered rays was verified using the scattering degradation factor. However, the FPD, which has recently been developed and is widely used in various areas, has greater response to radiation than analog devices and has a wide dynamic range. Therefore, the FPD is expected to maintain an appropriate level of resolution corresponding to the increase in the scattered-ray content ratio, which depends on filter thickness. Use of the FPD is also expected to minimize dose creep by reducing the exposure dose.

• Journal of Environmental Science International
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• v.30 no.8
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• pp.659-671
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• 2021

The physicochemical properties of soil and the yield and quality of rice (Oryza sativa L. cv. Sailmi) were assessed using Italian ryegrass (Lolium multiflorum Lam. cv. Kowinearly)-rice double cropping systems in the paddy fields at Goseong and Miryang in southern Korea. The average temperatures during the ripening period were approximately 1 ℃ higher than the optimal temperature for rice ripening and the sunshine duration was reduced by frequent rainfall. Consequently, it was slightly below the optimal conditions required for rice ripening. In the soil at Goseong, winter Italian ryegrass cropping increased the pH, electrical conductivity, and the contents of organic matter, total nitrogen (T-N), available P₂O₅, K, Ca, and Mg than winter fallowing. Particularly, the contents of T-N and available P₂O₅increased significantly. In the soil at Miryang, Italian ryegrass slightly increased the electrical conductivity and the T-N, Mg, and Na contents. Therefore, winter Italian ryegrass cropping improved the physicochemical properties of paddy soils; however, Italian ryegrass-rice double cropping slightly reduced the culm length at both Goseong and Miryang, without markedly changing the panicle length or number compared to fallow-rice cropping. Furthermore, at Goseong, Italian ryegrass-rice double cropping slightly decreased the spikelet number and milled rice yield, and increased the ripened grain rate; however, at Miryang, contrasting results were observed. In addition, fallow-rice cropping revealed no differences in the head rice or opaque rice rates. The protein content was slightly increased in Italian ryegrass-rice double cropping, without significant changes in the amylose content or Toyo value, compared to that in fallow-rice cropping. The peak and breakdown viscosities were slightly decreased. These results indicate that winter Italian ryegrass cropping might alter rice taste but may not exhibit remarkable negative effects on rice cultivation. Therefore, Italian ryegrass-rice double cropping system is recommended for paddy fields in southern Korea. Nevertheless, to increase the rice yield and quality, fertilization standards for rice cropping that consider the changes in the T-N and organic matter contents in paddy fields caused by winter Italian ryegrass cropping need to be established.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.510-519
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• 2021

Volatile Organic Compounds (VOCs) in sediments, which can cause human health problems, have been monitored in Korea since 2014. Measured VOC concentrations can be affected by matrix type and the volatility of target substances. In this study, (1) VOCs volatility and the influence of matrix interference were confirmed, and (2) internal standards (IS) method was applied to improve analytical method. For these purposes, method detection limit (MDL), calibration linearity, precision and accuracy of VOCs were compared in various matrices using the IS. Some of VOCs in sediments showed different peak areas and reduced rates compared to water matrix. It was suggested that adsorption properties of sediments hindered the migration to vapor during heat pretreatment in headspace method. A calibration curve was created in clean sand. Recovery rates for the calibration curve method and IS applying method were 64.1~83.1% and 99.1~119.3%, respectively. Relative standard deviations ranged from 11.1% to 21.6% for the calibration curve method and those for IS ranged 4.7% to 13.7%. In case of real sediment, calibration curve and 1,2-Dichlorobenzene-d4 (ODCB) among IS were not suitable. The average recovery rate of Fluorobenzene (FBZ) increased by 56.4% and Relative Standard Deviation (RSD) by 4.7%. However, the recovery rate was increased in the samples with large values of igniting intensity. This study confirmed that influence of the matrix of VOCs in sediment, and addition of IS materials improved precision and accuracy. Although IS corrects volatilization and adsorption, it is recommended that more than two types of IS should be added rather than single.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.2
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• pp.147-155
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• 2022

From March to August 2021, a total of 66 lip makeup products were collected from Seoul to measure the contents of lead, arsenic, cadmium, antimony, and nickel, and compared by product type (lip gloss, lip balm and lip tint), production area (domestic and imported), and user (for adults and children). The average metal contents were as follows; 0.284 ㎍/g for lead, 0.020 ㎍/g for arsenic, 0.003 ㎍/g for cadmium, 0.004 ㎍/g for antimony and 0.415 ㎍/g for nickel. The results of lip cosmetics were below the recommended maximums in regulations on safety standards for cosmetics of Ministry of Food and Drug Safety.

• Journal of Navigation and Port Research
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• v.46 no.4
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• pp.338-343
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• 2022

As the revitalization of the global maritime industry continues, the number of foreign ships navigating the maritime territories of maritime neighboring countries has rapidly increased. However, large-scale marine accidents have occurred, caused by the insufficient establishment of a system for management and operation relative to vessels' safety-condition. To address that, the IMO has granted the right to exercise port state control, especially for foreign vessels, to countries with jurisdiction over maritime territories with strengthening regulations and guidelines. In particular, the Republic of Korea, as a member of the TOKYO MOU, is conducting PSC, but as of 2020, the proportion of foreign ships was three times higher than that of national ships that called in domestic ports. However, the inspection rate was low at 9% which has not met the recommended level by the TOKYO MOU. Thus, this study conducted an IPA analysis as well as content analysis, by collecting the practical opinions and views of PSCO through objective questionnaires and written expert interviews, for improving the efficiency and effectiveness of domestic PSC. As a result, it was derived that the importance and performance related to human factors such as life on board, working environment, and response to safety accidents should be improved in to raise the quality of PSC inspection. Additionally, the work environment and performance of PSC in domestic ports for foreign vessels could be improved, if multifaceted support bases are established, for administrative unification of related tests for PSC, recruitment of PSCO, activation of the defection-reporting system, reorganization of the PSC execution group, etc.

• Journal of Nutrition and Health
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• v.55 no.5
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• pp.523-532
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• 2022

Vitamin C is an important physiological antioxidant which neutralizes reactive oxygen species (ROS) and reduces the oxidative stress in the body. Although it has been associated with various diseases, few studies have reported the dose-response relationship between vitamin C intake, storage and functions in the body, including its antioxidant function. The criteria to establish the Dietary Reference Intakes for Koreans (KDRIs) for vitamin C were based on the changes in plasma concentrations and saturation of leukocytes according to intake levels and the effects on antioxidant capacity and risk of metabolic diseases. When establishing the 2020 vitamin C KDRI, while there was no change in the criteria from those of 2015, the reference values were recalculated and revised to reflect changes such as the new standard weight by age. As the number of people consuming dietary supplements has increased over the last decade, only about 10% of adults consume less than the average total vitamin C, but the proportion of adolescents and elderly who consume less than the average is high. On the other hand, as the intake of vitamin C supplements increases, the proportion of people consuming excessive vitamin C is also increasing. There is a body of opinion that it is necessary to establish a vitamin C KDRI for smokers or people with chronic diseases such as the metabolic syndrome, but these standards have not been established due to the lack of supporting scientific evidence. As a result, studies to establish vitamin C KDRI for Korean smokers and patients with the metabolic syndrome, as well as studies on the excessive intake of vitamin C due to supplementation and interactions with other nutrients, are needed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.3
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• pp.213-223
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• 2023

A total of 81 handmade soaps on sale on the market were collected from January to November 2022. To compare quality characteristics, all ingredients were referred to, and the pH, dry reduction, heavy metals (lead, arsenic, cadmium, antimony, and mercury), and contents of free alkali were measured. All soaps had a slightly alkaline pH of 7.9 to 11.2, average drying loss was 17.6%, and free alkali was hardly detected. The average values of all heavy metals were 0.104 ㎍/g for lead, 0.035 ㎍/g for arsenic, 0.002 ㎍/g for cadmium, 0.048 ㎍/g for antimony, and 0.0003 ㎍/g for mercury. The results of handmade soap were below the recommended in regulations on safety standards for cosmetics of Ministry of Food and Drug Safety.

• The Journal of KAIRB
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• v.5 no.1
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• pp.21-32
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• 2023

Purspose: The purpose of this study is to examine the meaning and definition of vulnerable subjects in clinical trials in light of domestic and international regulations and guidelines, to analyze the contents of standard operation procedures (SOPs) among advanced general hospitals in Korea that conduct clinical trials, and to examine deliberation procedures for operation plans. Methods: The study examined how vulnerable research subjects were defined and described in related regulations and the classification of vulnerable research subjects presented in the IRB/HRPP SOPs of 18 clinical trial institutions, including 11 AAHRPP-accreditated general hospitals in Korea, as well as the operation of the IRB deliberation. Results: Among all domestic and international regulations and guidelines, only the The Council for International Organization of Medical Sciences (CIOMS) guidelines explain why vulnerability is related to judgments on the severity of physical, psychological, and social harm, why individuals are vulnerable, and for what reasons. However, the classification of vulnerable subjects by institutions differed from the classification by the International Conference on Harmonization-Good Clinical Practice (ICH-GCP). A total of the 16 institutions classified children and minors as vulnerable research subjects. 14 institutions classified subjects who cannot consent freely were classified as vulnerable subjects. 15 institutions classified sujects who can be affected by the organizational hierarchy were classified as vulnerable subjects. Subjects in emergency situations were regarded as vulnerable research subjects in 8 of institutions, while people in wards, patients with incurable diseases, and the economically poor including the unemployed were categorized as vulnerable research subjects in 7, 4, and 4 of institutions, respectively. Additionally, some research subjects were not classified as vulnerable by ICH-GCP but were classified as vulnerable by domestic institutions 15 of the institutions classified pregnant women and fetuses as vulnerable, 11 classified the elderly as vulnerable, and 6 classified foreigners as vulnerable. Conclution: The regulations and institutional SOPs classify subjects differently, which may affect subject protection. There is a need to improve IRBs' classifications of vulnerable research subjects. It is also necessary to establish the standards according to the differences in deliberation processes. Further, it is recommended to maintain a consistent review of validity, assessment of risk/benefit, and a review using checklists and spokeperson. The review of IRB is to be carried out in a manner that respects human dignity by taking into account the physical, psychological, and social conditions of the subjects.

• Korean Journal of Clinical Laboratory Science
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• v.54 no.1
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• pp.23-27
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• 2022

Disposable wet wipes provided by general restaurants in the Jeju Special Self-Governing Province were evaluated for compliance with the labeling requirements and the degree of bacterial contamination set by the Ministry of Food and Drug Safety. Of the 32 types of disposable wipes, five types of disposable wipes did not indicate the name and location of the business office of the manufacturer. Only 12 types of wet wipes were marked with the date of manufacture and expiration date. Bacterial contamination was seen in 9 types of wet wipes through bacterial culture but these were absent in the remaining 23 types (71.9%). The results of the antimicrobial susceptibility test for the 9 identified strains showed no methicillin-resistant coagulase-negative staphylococci (MRCNS) or multidrug-resistant bacteria. Through this study, it is recommended that the date of manufacture and expiration date must be indicated on the surface of disposable wet wipes designated as hygiene products, and clean uncontaminated wet wipes must comply with storage standards. In addition, the results are expected to contribute to the enhancement and improvement of hygiene management supervision, personal hygiene management, and an improvement in national health.

• Nutrition Research and Practice
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• v.16 no.sup1
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• pp.113-125
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• 2022

In the current years, it has now become necessary to establish standards for micronutrient intake based on scientific evidence. This review discusses issues related to the development of the 2020 Dietary Reference Intakes for Koreans (KDRI) for magnesium (Mg), zinc (Zn), and copper (Cu), and future research directions. Following issues were encountered when establishing the KDRI for these minerals. First, characteristics of Korean subjects need to be applied to estimate nutrient requirements. When calculating the estimated average requirement (EAR), the KDRI used the results of balance studies for Mg absorption and factorial analysis for Zn, which is defined as the minimum amount to offset endogenous losses for Zn and Mg. For Cu, a combination of indicators, such as depletion/repletion studies, were applied, wherein all reference values were based on data obtained from other countries. Second, there was a limitation in that it was difficult to determine whether reference values of Mg, Zn, and Cu intakes in the 2020 KDRI were achievable. This might be due to the lack of representative previous studies on intakes of these nutrients, and an insufficient database for Mg, Zn, and Cu contents in foods. This lack of database for mineral content in food poses a problem when evaluating the appropriateness of intake. Third, data was insufficient to assess the adequacy of Mg, Zn, and Cu intakes from supplements when calculating reference values, considering the rise in both demand and intake of mineral supplements. Mg is more likely to be consumed as a multi-nutrient supplement in combination with other minerals than as a single supplement. Moreover, Zn-Cu interactions in the body need to be considered when determining the reference intake values of Zn and Cu. It is recommended to discuss these issues present in the 2020 KDRI development for Mg, Zn, and Cu intakes in a systematic way, and to find relevant solutions.