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Toxic effect of chlorothalonil, an antifouling agent, on survival and population growth rate of a marine rotifer, Brachionus plicatilis (해산 로티퍼(Brachionus plicatilis)의 생존율 및 개체군 성장률을 이용한 신방오물질(Chlorothalonil)의 독성영향)

  • Heo, Seung;Lee, Ju-Wook;Choi, Hoon;Yoon, Sung-Jin;Kwon, Ki-Young;Hwang, Un-Ki;Park, Yun-Ho
    • Korean Journal of Environmental Biology
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    • v.39 no.3
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    • pp.390-398
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    • 2021
  • In this study, the toxicity of chlorothalonil was investigated using survival rate and population growth rate of a marine rotifer, Brachionus plicatilis, typically used in live food in marine aquaculture systems. The survival rate of B. plicatilis was determined after 24 h of exposure to chlorothalonil (0.010-0.156 mg L-1). Population growth rate of B. plicatilis was calculated after 72 h of exposure to chlorothalonil (0.078-1.250 mg L-1). The survival rate and population growth rate of B. plicatilis exposed to chlorothalonil in single-dose toxicity assessment showed concentration-dependent reductions. Survival rates of B. plicatilis exposed to chlorothalonil had the following values: NOEC, 0.020mg L-1; LOEC, 0.039 mg L-1; and EC50, 0.057 mg L-1. Population growth rate of B. plicatilis exposed to chlorothalonil had the following values: NOEC, 0.156 mg L-1; LOEC, 0.313 mg L-1; and EC50, 0.506 mg L-1. When the residual concentration of chlorothalonil in the marine coastal area was more than 0.039 mg L-1, it had a toxic effect on B. plicatilis, a zooplankton. This paper provides toxicity values that can be used as baseline data for organizing environmental standards of chlorothalonil. It also provides insight into toxic effects of chlorothalonil on other non-target organisms.

Emodin Studies on Anti-inflammatory and Skin Barrier Improvement Activities (Emodin의 항염 및 피부장벽개선 활성 연구)

  • Kim, Se-Gie;Choi, Jae Gurn;Jang, Young-Ah
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.6
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    • pp.1383-1392
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    • 2021
  • It has been reported that emodin, a major pharmacologically active ingredient of herbal medicines such as Polygonum cuspidatum, Polygonum multiflorum, Rheum palmatum, and Aloe vera, is effective in antioxidant, antibacterial, anti-inflammatory, anticancer, and liver protection. In this study, to investigate the potential of emodin to be used as a skin disease and functional material, the activity related to the improvement of inflammation and skin barrier function was confirmed. To observe the anti-inflammatory effect on HaCaT cells, which are human keratinocytes, cytokine inhibition was confirmed by ELISA kit and protein expression by western blot. In HaCaT cells activated with TNF-α (10 ng/mL)/IFN-γ (10 ng/mL), emodin was treated with each concentration (5, 10, 20, 40) µM. As a result, It was confirmed that the production amount of TNF-α, IL-1β and IL-6 decreased as the concentration of emodin increased. In the experimental results on the expression levels of inflammation-related proteins iNOS and COX-2, it was confirmed that 48% of iNOS and 29% of COX-2 were inhibited compared to control at a concentration of 20 µM of emodin. As an indicator of skin barrier function improvement, the mRNA expression level of filaggrin, involucrin, and loricirn and the production amount of filaggrin, involucrin, and loricirn were confirmed. and excellent results were obtained with an emodin concentration-dependent increase. In particular, filaggrin, which was produced twice as much as the control at a concentration of 20 µM, is a protein involved in the formation of NMF, a natural moisturizing factor, and is known to play an important role in moisturizing the stratum corneum. In conclusion, it was confirmed that emodin can be used as a material for improving inflammation and improving skin barrier function, which is part of the potential for use as a skin disease and functional material. It is believed that if additional research is performed in the future, the scope of its application can be further expanded.

Estimation of TROPOMI-derived Ground-level SO2 Concentrations Using Machine Learning Over East Asia (기계학습을 활용한 동아시아 지역의 TROPOMI 기반 SO2 지상농도 추정)

  • Choi, Hyunyoung;Kang, Yoojin;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.275-290
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    • 2021
  • Sulfur dioxide (SO2) in the atmosphere is mainly generated from anthropogenic emission sources. It forms ultra-fine particulate matter through chemical reaction and has harmful effect on both the environment and human health. In particular, ground-level SO2 concentrations are closely related to human activities. Satellite observations such as TROPOMI (TROPOspheric Monitoring Instrument)-derived column density data can provide spatially continuous monitoring of ground-level SO2 concentrations. This study aims to propose a 2-step residual corrected model to estimate ground-level SO2 concentrations through the synergistic use of satellite data and numerical model output. Random forest machine learning was adopted in the 2-step residual corrected model. The proposed model was evaluated through three cross-validations (i.e., random, spatial and temporal). The results showed that the model produced slopes of 1.14-1.25, R values of 0.55-0.65, and relative root-mean-square-error of 58-63%, which were improved by 10% for slopes and 3% for R and rRMSE when compared to the model without residual correction. The model performance by country was slightly reduced in Japan, often resulting in overestimation, where the sample size was small, and the concentration level was relatively low. The spatial and temporal distributions of SO2 produced by the model agreed with those of the in-situ measurements, especially over Yangtze River Delta in China and Seoul Metropolitan Area in South Korea, which are highly dependent on the characteristics of anthropogenic emission sources. The model proposed in this study can be used for long-term monitoring of ground-level SO2 concentrations on both the spatial and temporal domains.

Toxic Evaluation of Antifouling Paint (Irgarol and Diuron) using the Population Growth Rate of Marine Diatom, Skeletonema costatum (해산 규조류(Skeletonema costatum)의 개체군 성장률 분석을 이용한 신방오도료(Irgarol, Diuron)의 독성평가)

  • Lee, Ju-Wook;Choi, Hoon;Park, Yun-Ho;Lee, Seung-Min;Choi, Yoon-Seok;Heo, Seung;Hwang, Un-Ki
    • Journal of Marine Life Science
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    • v.5 no.1
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    • pp.9-16
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    • 2020
  • We evaluated the toxic effects of antifouling paint (irgarol and diuron) on the population growth rate (r) of the marine diatom, Skeletonema costatum. The r of S. costatum was determined after 96 hrs of exposure to irgarol (0, 0.31, 0.63, 1.25, 2.5 and 5 ㎍ l-1) and diuron (0, 7.81, 15.63, 31.25, 62.5 and 125 ㎍ l-1). It was observed that r in the control (absence of irgarol and diuron) were greater than 0.04, while r in the treatment groups decreased with increasing irgarol and diuron concentrations. Irgarol and diuron reduced r in a dose-dependent manner with significant decreases occurring at concentrations above 0.63 and 15.63 ㎍ l-1, respectively. The EC50 values of r in irgarol and diuron exposure were 1.09 and 45.45 ㎍ l-1. No observed effect concentration (NOEC) were 0.31 and 7.81 ㎍ l-1, the lowest observed effect concentration (LOEC) were 0.63 and 15.63 ㎍ l-1. This result indicate that a concentration of greater than 0.63 ㎍ l-1 of irgarol and 15.63 ㎍ l-1 of diuron in marine ecosystems induced to decreasing r of S. costatum. Also, these toxic values can be useful as a baseline data for the toxic evaluation of irgarol and diuron in marine ecosystems.

Shipping Industry Support Plan based on Research of Factors Affecting on the Freight Rate of Bulk Carriers by Sizes (부정기선 운임변동성 영향 요인 분석에 따른 우리나라 해운정책 지원 방안)

  • Cheon, Min-Soo;Mun, Ae-ri;Kim, Seog-Soo
    • Journal of Korea Port Economic Association
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    • v.36 no.4
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    • pp.17-30
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    • 2020
  • In the shipping industry, it is essential to engage in the preemptive prediction of freight rate volatility through market monitoring. Considering that freight rates have already started to fall, the loss of shipping companies will soon be uncontrollable. Therefore, in this study, factors affecting the freight rates of bulk carriers, which have relatively large freight rate volatility as compared to container freight rates, were quantified and analyzed. In doing so, we intended to contribute to future shipping market monitoring. We performed an analysis using a vector error correction model and estimated the influence of six independent variables on the charter rates of bulk carriers by Handy Size, Supramax, Panamax, and Cape Size. The six independent variables included the bulk carrier fleet volume, iron ore traffic volume, ribo interest rate, bunker oil price, and Euro-Dollar exchange rate. The dependent variables were handy size (32,000 DWT) spot charter rates, Supramax 6 T/C average charter rates, Pana Max (75,000 DWT) spot charter, and Cape Size (170,000 DWT) spot charter. The study examined charter rates by size of bulk carriers, which was different from studies on existing specific types of ships or fares in oil tankers and chemical carriers other than bulk carriers. Findings revealed that influencing factors differed for each ship size. The Libo interest rate had a significant effect on all four ship types, and the iron ore traffic volume had a significant effect on three ship types. The Ribo rate showed a negative (-) relationship with Handy Size, Supramax, Panamax, and Cape Size. Iron ore traffic influenced three types of linearity, except for Panamax. The size of shipping companies differed depending on their characteristics. These findings are expected to contribute to the establishment of a management strategy for shipping companies by analyzing the factors influencing changes in the freight rates of charterers, which have a profound effect on the management performance of shipping companies.

Effect of 17β-estradiol on Ecdysteroid Pathway Related Genes in the Brackish Water Flea Diaphanosoma celebensis (17β-estradiol이 기수산 물벼룩의 Ecdysteroid 경로에 미치는 영향)

  • In, Soyeon;Yoo, Jewon;Cho, Hayoung;Lee, Young-Mi
    • Journal of Marine Life Science
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    • v.5 no.2
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    • pp.35-42
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    • 2020
  • 17β-estradiol (E2) is a natural hormone secreted by ovary, and continuously discharged from household and livestock wastewater into aquatic environment. Due to its strong estrogenic activity, it has adverse effects on development and reproduction in crustacean as an endocrine disrupting chemical. Although ecdysteroid signaling pathway play a key role in development in crustacean, little information on transcriptional modulation of ecdysteroid-related genes in response to E2 is available in small crustacean. Here, we investigated the acute toxicity of E2 to obtain 24-h LCx values in the brackish water flea Diaphanosoma celebensis. Time-dependent expression patterns of seven ecdysteroid pathway - related genes (CYP314a1, EcRA, EcRB, USP, ERR, Vtg, VtgR) were further examined using quantitative real time reverse transcriptase polymerase chain reaction (qRT-PCR). As results, 24-h LC50 and LC10 values were 9.581 mg/l and 4.842 mg/l, respectively. The mRNA expression of CYP314a1, EcRA, USP, VtgR was significantly up-regulated at 12 or 24 h after exposure to E2. These findings indicate that E2 can affect their molting and reproduction by modulating the expression of ecdysteroid pathway - related in D. celebensis. This study will be useful for better understanding of molecular mode of action of endocrine disrupting chemicals on molting process in small crustacean.

The Effect of Alcohol Availability on Drinking Behavior : A Multilevel Analysis on Urban Regions (알코올가용성이 음주행태에 미치는 영향: 도시지역을 대상으로 한 다수준 분석)

  • Kwon, RIA;Shin, Sangsoo;Shin, Young-jeon
    • 한국사회정책
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    • v.25 no.2
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    • pp.125-163
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    • 2018
  • Social and health problems related to drinking are serious. Drinking behavior is affected not only by personal factors but also by environment factors. The purpose of this study is to find out how the alcoholic beverage stores in community influence the drinking behaviors of individuals after adjusting the individual level variables and provide it as basic data for alcohol related regulatory policies. In order to identify the factors affecting drinking behavior, we conducted a multilevel logistic regression analysis with high-risk drinking and current drinking as dependent variables. Individual-level data provided by 2015 community health survey from respondents of urban residents, and regional level data provided by the National Statistical office. The variables such as age, education level, and income level were used as individual level variables and the number of basic living allowances, divorce rate, and the number of pubs were used as community level variables. According to the research results, after controlling all variables, the number of bar, retail per $1km^2$ in residential area effect on current drinking. But, they are not effect on high risk drinking. In the high risk drinking, only the divorce rate effect on drinking behavior. As a result of the stratified analysis, there was no difference in the current drinking. But, it shows that the higher the number of retail stores and the total alcohol availability, the higher risk drinking behavior in the 60s. The results of this study suggest that policies aimed not only on individuals but also on the local environment are necessary.

Differences in Grip Strength by Living Conditions and Living Area among Men and Women in Middle and Later Life (독거여부와 거주지역에 따른 중년기와 노년기 남성과 여성의 악력 차이)

  • Joo, Susanna;Jun, Hey Jung;Park, Hayoung
    • 한국노년학
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    • v.38 no.3
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    • pp.551-567
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    • 2018
  • Demographic and socio-structural information is useful to identify potential welfare recipients who are in need of disease-prevention and intervention services. Thus, the present study aims to explore the differences in grip strength among middle and old-aged adults by living conditions and by living area. The 5th wave data of Korean Longitudinal Study of Aging was utilized. The dependent variable was grip strength, and the independent variables were living alone (living alone or not) and living area (city or non-city). Covariates were age, education, log-transformed household income, spouse existence, body mass index, self-rated health conditions, depressive symptoms, cognitive function, smoking, regular exercise, frequency of meeting with friends, and the number of social participation. Regression analysis was performed for middle-aged men, middle-aged women, old-aged men, and old-aged women, respectively. ANOVA and Chi-test were additionally used to specifically discuss significant results. Cross-sectional weight was applied to all analyses. According to the results, living alone and living area did not have significant effects on grip strength among middle-aged men, old-aged men, and old-aged women. In middle-aged women, however, living alone and living area were significantly associated with grip strength. To be specific, middle-aged women who lived alone in rural areas had the lowest grip strength compared to other middle-aged women. Additional analysis showed that middle-aged women who lived alone in rural areas had risk factors, such as low education level, low income, or high depressive symptoms. It implies that middle-aged women living alone in rural areas may have physical health risks, so they might be in need of disease prevention. This study is meaningful in that it can provide reliable information on the latent welfare recipients by using representative panel data and applying weight values.

Latitude within Judgement and Virtue (판단력과 덕 그리고 활동여지)

  • Kim, Duk-soo
    • Journal of Korean Philosophical Society
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    • v.142
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    • pp.1-25
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    • 2017
  • Kant's doctrine of virtue shows how an actor should behave morally in an individual situation with moral law defines the limits of human action. There is latitude for action in the course of formulating the maxims of action by an actor. And moral judgement, as Aristotle's Pronesis, is very important in the latitude for action. In the doctrine of virtue, Kant suggests two kinds of duty of virtue: one's own perfeciton as an obligatory end, and the happiness to others as an obligatory end-and raises the question of casuistics for each. However, this was the practice and training for the human moral life by application of the moral law. In particular, Kant saw that ethics does not give laws for action, but only give laws for the maxims of action, and further intended to realize the practice in a proper way of seeking truth through casuistical questions. Thus, Kant points out that the casuistic is related only to ethics in a fragmentary way and is added to ethics only as a comment on the system. According to Kant, virtue and judgment are inevitable to apply categorical imperative in the empirical and realistic world. In other words, virtue and judgment are necessary to enable people who are likely to act in accordance to inclination to live a moral life in accordance with the command of reason. Thus Kant saw that in order to take wide duty into narrow ones, human beings must not only have to cultivate virtues as a strong power of will, but also to exercise judgment. In addition, the distinction between duty of law(narrow obligation) and duty of virtue(wide obligation) is dependent on whether there is a latitude for action in the application of both duties. So the role of virtue and training of judgement is very important in the latitude for action that occurs in the process of formalizing actor's maxims. In detail, as the duty is wider, so man's obligation to action is more imperfect, but the closer to narrow duty(Law) he brings the maxim of observing this duty(in his attitude of will), so much the more perfect is his virtuous action. Thus, it was an effort to show how Kant's best moral principles, that is categorical imperative could be applied to the real world at the time of criticism. Of course, even if it is difficult to assess Kant's efforts as successful, criticizing Kant's ethics as 'formal', 'abstract', or 'monologous' is not persuasive because of critics did not understand his ethics as a whole.

Optimization of β-Glucan Extraction Process from Rice Bran and Rice Germ Using Response Surface Methodology (미강과 배아로부터 β-glucan의 추출조건 최적화 및 기능성 생리활성)

  • Jeon, Ju-Yeong;Park, Ji-Hae;Kim, Se-Hwan;Choi, Yong-Hee
    • Food Engineering Progress
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    • v.13 no.1
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    • pp.8-15
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    • 2009
  • This study was investigated on optimal conditions of the functional activities of ${\beta}$-glucan which was extracted from rice bran (RB) and rice germ (RG) using response surface methodology. The extraction temperature was varied in the $80-100^{\circ}C$, the extraction time between 2-10 min, and the ethanol concentration was in the interval of 30-70%. A central composite design was applied to investigate the effects of independent variables of extraction temperature ($X_1$), extraction time ($X_2$) and ethanol concentration ($X_3$) on dependent variables such as electron donating ability of RB ($Y_1$), electron donating ability of RG ($Y_2$), total phenolics of RB ($Y_3$), total phenolics of RG ($Y_4$), ${\beta}$-glucan contents of RB ($Y_5$) and ${\beta}$-glucan contents of RG ($Y_6$). As a result, the highest $Y_1$ level was 84.02% at $92.60^{\circ}C$, 2.75 min and 60.41% in saddle point. This value was affected by extraction temperature (P<0.05). The value of $Y_2$ was found to be the highest at $87.52^{\circ}C$, 2.23 min and 54.40% in saddle point. The highest $Y_3$ level was $98.56^{\circ}C$, 6.69 min and 40.26% in saddle point, and this extraction was greatly influenced by extraction temperature (P<0.01) and ethanol concentration (P<0.05). The value of $Y_4$ was found to be highest at $95.73^{\circ}C$, 9.19 min and 53.67% in minimum point. The value of $Y_5$ was found to be the highest at $96.23^{\circ}C$, 7.70 min and 63.69% in saddle point. The value of $Y_6$ was found to be highest at $87.82^{\circ}C$, 2.10 min and 50.03% in minimum point, and this extraction was greatly influenced by extraction time (P<0.01).