• Journal of Biomedical Engineering Research
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• v.45 no.1
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• pp.49-55
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• 2024

Accurate measurement of blood pressure is essential for classifying an individual's disease, identifying blood pressure-related risks, and managing health. Due to the environmental and health hazards of mercury sphygmomanometers, automatic sphygmomanometers using the oscillometric method are widely used in hospitals as well as in general homes, and have established themselves as a practical standard sphygmomanometer. In this study, we developed a blood pressure simulator using an actuator that provides simulated pressure to an automatic blood pressure cuff. The developed blood pressure simulator adopts an arm-shaped cylindrical shape similar to the situation in which a person measures blood pressure with an automatic blood pressure monitor, and implements a method of transmitting pressure to the cuff using a pressure plate. Accuracy was evaluated through the mean and standard deviation of the difference with the commercialized blood pressure simulator BP PUMP 2, and reproducibility was confirmed using two automatic blood pressure monitors. The developed blood pressure simulator enables automatic blood pressure monitoring in a simple manner and also meets the evaluation standards for accuracy and reproducibility. In the future, as a standardized blood pressure simulator, it is expected to be of great help in evaluating and verifying the performance of automatic blood pressure monitors by supplementing precise hardware and software and building a blood pressure database.

• Korean Journal of Ecology and Environment
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• v.34 no.1 s.93
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• pp.45-53
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• 2001

Transport of cyanobacterial toxins (microcystin-LR, -RR, -YR) were assessed from a eutrophic lake, Lake Suwa, through the outflowing river, the Tenryu River, and its irrigation channel branch. Temporal variation of phytoplankton species composition in the river coincided with those of the lake; Microcystis ichthyoblabe dominated from June to July, and M. viridis dominated from August to September. When cyanobacterial bloom occurred, microcystins were continuously detected at the concentration of $0.3{\sim}3.2\;{\mu}g/l$ even at 32 km downstream. The change of the content of three microcystin variants were related both with the total cell density of Microcystis and with the change of Microcystis species composition. When Microcystis ichthyoblabe dominated during July, only microcystin-RR (MC-RR) and -LR (MC-LR) were detected, while when Microcystis viridis dominated between August and October, microcystin-RR,-YR (MC -YR) and -LR were detected. Along 29 km flowing distance (flow time 11 hours) between site 2 and site 5 in the Tenryu River, cyanobacterial density and microcystin concentration were reduced by 73% and 72%, respectively, which is mostly contributed by the dilution effect of tributary waters (61% and 57%, respectively) . In the artificial irrigation channel microcystins and cyanobacterial cells were decreased less than in the natural river. The results indicate that cyanobacterial toxins can be transported far downstream without much removal and give hazards to water usage in downstream of eutrophic lakes with cyanobacterial blooms.

• Journal of Food Hygiene and Safety
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• v.33 no.1
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• pp.12-22
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• 2018

The US government has enacted the Food Safety Modernization Act (FSMA) in 2011, which is being phased in and planned. The final Rules of Produce Safety focus on biological hazards related to agricultural production, harvesting, packaging and storage, which are being phased in since 2017 depending on farm scale. As a result of comparison with the Korean-GAP (Good Agricultural Practices) standards, it is difficult to compare the two standards to be compared with each other by 1:1. However, many of the Korean-GAP standards are similar to FSMA Produce Safety rules. However, the Korean-GAP standards can be judged differently according to the evaluator as a comprehensive standard, so the details of the standards need to be reinforced. In terms of the provisions, the Korean-GAP standards are the most appropriate for the safety of workers (FSMA Subpart D), followed by livestock and wild animals (FSMA Subpart I), buildings, equipment and tools (FSMA Subpart L) and harvesting activities (FSMA Sub-part K). However, there are some weaknesses in the field of agricultural water management (FSMA Subpart E) and farm manager's qualifications and training (FSMA Subpart C), and the response to the biological soil amendments of animal origin and human waste (FSMA Subpart F) is weak. The FSMA regulation is not a certification standard, but it is expected that the marbling effect, which is the standard laid down by the United States leading the world food safety standards, is expected to be considerable. Therefore, we hope that the review of the Korean-GAP standards will help improve the quality of agricultural products and expand our exports, since the standard for responding to microbiological safety emphasized in the FSMA regulations is the Korean-GAP standard.

• Korean Journal of Biological Psychiatry
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• v.24 no.1
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• pp.19-25
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• 2017

Previous studies have found that firefighters have a tenfold higher prevalence of Parkinson's disease (PD) compare to the general population. Firefighters are constantly exposed to various occupational hazards including toxic chemicals of fire residue and the toxic chemicals can effects development and progression of PD. Nevertheless, there were no studies about the association between exposure to chemical byproducts of combustion and the development of PD among firefighters. Thus the aim of this study is to look into existing researches regarding the effect of chemical byproducts of combustion on the development of PD. An extensive literature search was conducted to identify harmful chemical components of smoke and fire residue, using the PubMed database during November of 2016. We searched for relevant articles by combining several keywords that contained "Parkinson's disease" and each of the different toxic chemicals, yielding a total of 1401 articles. After applying the selection criteria, 12 articles were chosen. Chemical substances reported to have a harmful effect on PD, in at least one article, were carbon monoxide, toluene, manganese and lead. Carbon monoxide and metal substances including manganese and lead were found to be associated with an increased PD risk in more than two articles. There was a heightened risk of PD in firefighters due to exposure of chemical byproducts of combustion including carbon monoxide, toluene, manganese and lead. However, to the best of our knowledge, to support this result we need more systematic epidemiological studies about these risk factors of PD among firefighters. In addition, further studies for the effects of prolonged exposure to toxic fire residue on the development and progression of PD in firefighters are needed.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.595-606
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• 2018

Objective: The Fusarium mycotoxins of deoxynivalenol (DON) and zerolenone (ZEN) cause health hazards for both humans and farm animals. Therefore, the main intention of this study was to reveal DON and ZEN effects on the mRNA expression of pro-inflammatory cytokines and other immune related genes in the liver of piglets. Methods: In the present study, 15 six-week-old piglets were randomly assigned to the following three different dietary treatments for 4 weeks: control diet, diet containing 8 mg DON/kg feed, and diet containing 0.8 mg ZEN/kg feed. After 4 weeks, liver samples were collected and sequenced using RNA-Seq to investigate the effects of the mycotoxins on genes and gene networks associated with the immune systems of the piglets. Results: Our analysis identified a total of 249 differentially expressed genes (DEGs), which included 99 upregulated and 150 downregulated genes in both the DON and ZEN dietary treatment groups. After biological pathway analysis, the DEGs were determined to be significantly enriched in gene ontology terms associated with many biological pathways, including immune response and cellular and metabolic processes. Consistent with inflammatory stimulation due to the mycotoxin-contaminated diet, the following Kyoto encyclopedia of genes and genomes pathways, which were related to disease and immune responses, were found to be enriched in the DEGs: allograft rejection pathway, cell adhesion molecules, graft-versus-host disease, autoimmune thyroid disease (AITD), type I diabetes mellitus, human T-cell leukemia lymphoma virus infection, and viral carcinogenesis. Genome-wide expression analysis revealed that DON and ZEN treatments downregulated the expression of the majority of the DEGs that were associated with inflammatory cytokines (interleukin 10 receptor, beta, chemokine [C-X-C motif] ligand 9), proliferation (insulin-like growth factor 1, major facilitator superfamily domain containing 2A, insulin-like growth factor binding protein 2, lipase G, and salt inducible kinase 1), and other immune response networks (paired immunoglobulin-like type 2 receptor beta, Src-like-adaptor-1 [SLA1], SLA3, SLA5, SLA7, claudin 4, nicotinamide N-methyltransferase, thyrotropin-releasing hormone degrading enzyme, ubiquitin D, histone $H_2B$ type 1, and serum amyloid A). Conclusion: In summary, our results demonstrated that high concentrations DON and ZEN disrupt immune-related processes in the liver.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.717-724
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• 2010

The flash point is one of the most important physical properties used to determine the potential for fire and explosion hazards of flammable liquids. Despite the needs of the experimental flash point data for the design and construction of chemical plants, there is often a significant gap between the demands for the data and their availability. This study have built and compared two models of partial least squares(PLS) and support vector machine(SVM) to predict the experimental flash points of 893 organic compounds out of DIPPR 801. As the independent variables of the models, 65 functional groups were chosen based on the group contribution method that was oriented from the assumption that each fragment of a molecule contributes a certain amount to the value of its physical property, and the logarithm of molecular weight was added. The prediction errors calculated from cross-validation were employed to determine the optimal parameters of two models. And, an optimization technique should be used to get three parameters of SVM model. This work adopted particle swarm optimization that is one of heuristic optimization methods. As the selection of training data can affect the prediction performance, 100 data sets of randomly selected data were generated and tested. The PLS and SVM results of the average absolute errors for the whole data range from 13.86 K to 14.55 K and 7.44 K to 10.26 K, respectively, indicating that the predictive ability of the SVM is much superior than PLS.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.274-284
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• 2016

Purpose: The purpose of this work is to describe the spectrometric analysis of gaseous cloud formation over reactor mixed uranium-and-plutonium (UP) fuel $(U_{0.8}Pu_{0.2})O_2$ samples heated to a temperature $>2,000^{\circ}C$, and thus forecast and evaluate radiation hazards threatening humans who cope with the consequences of any accident at a fission reactor loaded by UP mixed oxide $(U_{0.8}Pu_{0.2})O_2$, such as a mixture of 80% U and 20% Pu in weight. Materials and methods: The UP nuclear fuel samples were heated up to a temperature of over $2,000^{\circ}C$ in a suitable assembly (apparatus) at out-of-pile experiments' implementation, the experimental in-depth study of metabolism of active materials in living organisms by means of artificial irradiation of pigs by plutonium. Spectrometric measurements were carried out on the different exposed organs and tissues of pigs for the further estimation of human internal exposure by nuclear materials released from the core of a fission reactor fueled with UP mixed oxide. Results: The main results of the research described are the following: (1) following the research on the influence of mixed fuel fission products (radioactive isotopes being formed during reactor operation as a result of nuclear decay of elements included into the fuel composition) on living organisms, the authors determined the quantities of plutonium dioxide ($PuO_2$) that penetrated into blood and lay in the pulmonary region, liver, skeleton and other tissues; and (2) experiments confirmed that the output speed of plutonium out of the basic precipitation locations is very small. On the strength of the experimental evidence, the authors suggest that the biological output of plutonium can be disregarded in the process of evaluation of the internal irradiation doses.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.33-38
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• 2019

Ochratoxin A (OTA), one of mycotoxins produced mainly by Aspergillus is a common contaminant of stored grains, posing health hazards to human and livestock. The aim of this study is to explore ability of isolated bacteria Bacillus subtilis AF13 and Streptomyces shenzhenensis YR226 to remove OTA. AF13 and YR226 could remove 94.23 and 97.73% of OTA ($100{\mu}g/L$), respectively during 24 h incubation in NB medium. When cultures of two strains were separated into washed cells and cell-free supernatant, the supernatant of both strains removed more than 90% of $100{\mu}g/L$ OTA, and 98.88% of OTA could be also removed by the washed cells of YR226. OTA removal occurred in a few second by the supernatant of both strains, and treatments of autoclaving, proteinase K and chymotrypsin did not affect the OTA removal by the culture supernatants, which indicate that some thermostable and non-proteinaceous substances secreted by these bacteria may be involved in OTA removal in these two bacteria. These results suggest that AF13 and YR226 can be used to remove OTA from OTA-contaminated grains and feeds, and therefore decrease economic damage in agriculture and feed industry.

• Korean Journal of Biological Psychiatry
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• v.28 no.1
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• pp.13-22
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• 2021

Objectives Despite growing attention to anxiety in bipolar disorder (BD), little research has assessed anxiety symptoms in the course of BD. The current prospective follow-up study examines the influence of subjectively and objectively measured anxiety symptoms on the course of BD. Methods A total of 49 patients with BD were followed-up prospectively for average of one year at an average of four months interval. The Korean version of the Beck Anxiety Inventory (K-BAI), the Hamilton Anxiety Rating Scale, heart rate variability (HRV) were used to measure anxiety subjectively, objectively and physiologically. Participants were divided into high and low anxiety groups based on their K-BAI scores. Kaplan-Meier survival analysis was performed to compare the recurrence of mood episode, suicide attempt, emergency room visit, and psychiatric hospitalization between two groups. Mediators were investigated with Cox proportional hazards models. Results Compared to the low anxiety group, the high anxiety group reported significantly higher impulsiveness (p = 0.016) and lower high frequency component on HRV (p = 0.007) after controlling for severity of BD. Regarding survival analysis, the high anxiety group showed hastened depressive episode recurrence (p = 0.048) and suicidal ideation was the mediator of the hazard ratio (HR) 1.089 (p = 0.029) in the Cox model. Moreover, the high anxiety group showed a tendency of accelerated suicide attempt (p = 0.12) and impulsivity was the risk factor of suicide attempt (HR = 1.089, p = 0.036). Conclusions This interim analysis of prospective study suggests that high anxiety level in BD may anticipate unfavorable course. Further studies are needed to understand the multifactorial mechanism of anxious bipolar patients.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.79-87
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• 2021

Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.