• Journal of the Ergonomics Society of Korea
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• 제30권5호
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• pp.671-681
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• 2011

Objective: The purpose of this study is to compare the workload level at each lower limbs posture and suggest the ergonomic workstation guideline for working period by evaluating the imbalanced lower limbs postures from the physiological and psychophysical points of view. Background: Many workers like welders are working in various imbalanced lower limbs postures either due to the narrow working conditions or other environmental conditions. Method: Ten male subjects participated in this experiment. Subjects were asked to maintain 3 different lower limbs postures(standing, squatting and bending) with 3 different working conditions(balanced floor with no scaffold, imbalanced floor with 10cm height of scaffold, and imbalanced floor with 20cm height of scaffold). EMG data for the 4 muscle groups(Retus Femoris, Vastus Lateralis, Tibialis Anterior, Gastrocnemius) from each lower limbs posture were collected for 20 seconds every 2 minutes during the 8 minutes sustaining task. Subjects were also asked to report their discomfort ratings of body parts such as waist, upper legs, lower legs, and ankle. Results: The ANOVA results showed that the EMG root mean square(RMS) values and the discomfort ratings(CR-10 Rating Scale) were significantly affected by lower limbs postures and working time(p<0.05). The correlation was analyzed between the EMG data and the discomfort ratings. Also, prediction models for the discomfort rating for each posture were developed using physical condition, working time, and scaffold height. Conclusion: We strongly recommend that one should not work more than 6 minutes in a standing or squatting postures and should not work more than 4 minutes in a bending posture. Application: The results of this study could be used to design and assess working environments and methods. Furthermore, these results could be used to suggest ergonomic guidelines for the lower limbs postures such as squatting and bending in the working fields in order to prevent fatigue and pain in the lower limbs body.

• Proceedings of the KSME Conference
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1687-1692
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• 2004

Airflow in the nasal cavity of a normal Korean adult is investigated experimentally by tomographic PIV measurement. Knowledge of airflow characteristics in nasal cavities is essential to understand the physiology and pathology aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. All of these researches on nasal airflow are under the condition of constant flow-rate. In this study, nasal cavity flow with the physiological period is investigated by tomographic PIV, for the first time. A pumping system that can produce the periodic flow is created. Thanks to a new method for the model casting by a combination of the rapid prototyping and curing of clear silicone, a transparent rectangular box containing the complex nasal cavity can be made for PIV. The CBC PIV algorithm is used for analysis. Phase-averaged mean and RMS velocity distributions are obtained for inspirational and expiration nasal airflows. The comparison with the constant flow case is appreciated. There exist many flow patterns depending on each phase.

• Journal of Physiology & Pathology in Korean Medicine
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• 제23권6호
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• pp.1460-1464
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• 2009

In spite of many studies on statistical model for pattern identifications (PIs), little attention has been paid to the complexity of pattern diagnosis processed by oriental physicians. The aim of this study is to develop a statistical diagnostic model which discriminates four PIs using multiple indicators in stroke. Clinical data were collected from 981 stroke patients and 516 data of which PIs were agreed by two independent physicians were included. Discriminant analysis was carried out using clinical indicators such as symptoms and signs which referred to pattern diagnosis, and applied to validation samples which contained all symptoms and signs manifested. Four Fischer's linear discriminant models were derived and their accuracy and prediction rates were 93.2% and 80.43%, respectively. It is important to consider the pattern diagnosis processed by oriental physicians in developing statistical model for PIs. The discriminant model developed in this study using multiple indicators is valid, and can be used in the clinical fields.

• The Journal of Korean Society for School & Community Health Education
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• 제2권1호
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• pp.53-65
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• 2001

The purposes of this study were to collect basic data on education of Sexuality(Health education) of consciousness & value of sexuality of elementary school children. 584,6th grade students in elementary school in Yong-In city were analysed and the results are as follow; 1. Knowledges of sexuality for children was at a average level, especially "physical change of puberty" and "sexual violence" were well recognized but "the physical characteristics of male & female" and "physiological phenomena of men" were less recognized. Attitudes of sexuality were positive for "relationship with partners" and "expression of mind". Practices of sexuality were at a low rate in the case of "shaking hands with partner" and "experience of sexual behavior". The Value of sexuality was at a high rates in the case of "the role of sex", "equality" & "self-identification", therefore students need good education of sexuality from childhood 2. Sexuality education of students increased knowledges of sexuality as a consciousness. There was no relationship between attitudes and pratices of sexuality. Educated children valued sexuality move highly than uneducated children. This result shows that education is needed with regard to both the knowledge and value of sexuality in a planned system. We need some program to provide more information on sexual attitudes and practices. 3. There was a high correlation between the consciousness of sexuality and value placed on it. As sexual awareness increases amongst students codes of morality develop Positive sexual attitudes served as good role models for sex. In particular positive sexual attitudes have a big effect on sexual values. In addition, as sexual awareness and attitude increase amongst students the role of sexual development. The elementary school phase sexual values are developed and determined. It is therefore an important phase.

• Safety and Health at Work
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• 제2권2호
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• pp.169-175
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• 2011

Objectives: The questionnaire of occupational stress index (OSI) has been popular in the workplace, and it has been tailored for bus drivers in Taiwan. Nevertheless, its outcomes for participants are based on self-evaluations, thus validation by their physiological stress biomarker is warranted and this is the main goal of this study. Methods: A cross-sectional study of sixty-three city bus drivers and fifty-four supporting staffs for comparison was conducted. Questionnaire surveys, 24-hour urine cortisol testing, and blood draws for dehydroepiandrosterone-sulfate (DHEA-S) testing were performed. The measured concentrations of these biological measures were logarithmically transformed before the statistical analysis where various scores of stressor factors, moderators, and stress effects of each OSI domain were analyzed by applying multiple linear regression models. Results: For drivers, the elevated 24-hour urine cortisol level was associated with a worker's relationship with their supervisor and any life change events in the most recent 3 months. The DHEA-S level was higher in drivers of younger age as well as drivers with more concerns relating to their salary and bonuses. Non-drivers showed no association between any stressor or satisfaction and urine cortisol and blood DHEA-S levels. Conclusion: Measurements of biomarkers may offer additional stress evaluations with OSI questionnaires for bus drivers. Increased DHEA-S and cortisol levels may result from stressors like income security. Prevention efforts towards occupational stress and life events and health promotional efforts for aged driver were important anti-stress remedies.

• Journal of Biomedical Engineering Research
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• 제40권5호
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• pp.143-150
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• 2019

To evaluate the toxicity of ophthalmic drug, the Draize test and Bovine Corneal Opacity and Permeability (BCOP) test commonly used. In Draize test, experimental animals were under stress and pain due to long-term exposure of drug. In addition, regarding physiological functions, animal model is not perfectly reflected a human eye condition. Although some models such as $EpiOcular^{TM}$, HCE model, LabCyte Cornea-Model, and MCTT $HCE^{TM}$ were already presented advanced cornea ex-vivo model to replace animal test. In this sense, cornea tissue structure mimicked ex-vivo toxicity model was fabricated in this study. The corneal epithelial cells (CECs) and keratocytes (CKs) isolated from rabbit eyeball were seeded on non-patterned silk film (n-pSF) and patterned silk film (pSF) at $32,500cells/cm^2$ and $6,500cells/cm^2$. Sequentially, n-pSF and pSF were stacked to mimic a multi-layered stroma structure. The thickness of films was about $15.63{\mu}m$ and the distance of patterns was about $3{\mu}m$. H&E stain was performed to confirm the cell proliferation on silk film. F-actin of CKs was also stained with Phalloidin to observe the cytoskeletal alignment along with patterns of the pSF. In the results, CECs and CKs were shown the good cell attachment on the n-pSF and pSFs. Proliferated cells expressed the specific phenotype of cornea epithelium and stroma. In conclusion, we successfully established the ex-vivo cornea toxicity model to replace the eye irritation tests. In further study, we will set up the human ex-vivo cornea toxicity model and then will evaluate the drug screening efficacy.

• Journal of Physiology & Pathology in Korean Medicine
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• 제33권5호
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• pp.275-281
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• 2019

Polysaccharides produced in microorganisms and plants are known to increase the immune response in the body. We proposed analysis of beta-glucan contents of phellinus linteus fruit body (FB) and mycelium (MC) cultured in cudrania tricuspidata. Also, we examined whether fruit body and mycelium can increase the immune response in cyclophosphamide-induced immunosuppression animal models. We injected cyclophosphamide (50 mg/kg) twice to produce immunosuppression mice. Then, FB (200 mg/kg) and MC (200 mg/kg) were oral administered for 14 days. In order to confirm the immune-enhancing effect of FB and MC, we analyzed spleen weight, the number of immune cells, cytokines, and immunoglobulins levels. Cyclophosphamide decreased the weight of spleen, the number of immune cells. However, FB and MC have significantly increased the weight of spleen, the number of white blood cell, lymphocyte and monocyte. In addition, they have significantly increased immune-related cytokines (IL-2 and IFN-${\gamma}$) and immunoglobulins (IgA, IgG, IgM) levels. As a results, phellinus linteus fruit body (FB) and mycelium (MC) cultured in cudrania tricuspidata can be used as effective natural materials for immune-enhancing.

• Asian-Australasian Journal of Animal Sciences
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• 제32권2호
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• pp.290-296
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• 2019

Objective: Pigs share many physiological, anatomical and genomic similarities with humans, which make them suitable models for biomedical researches. Understanding the genetic status of Yucatan miniature pigs (YMPs) and their association with human diseases will help to assess their potential as biomedical model animals. This study was performed to identify non-synonymous single nucleotide polymorphisms (nsSNPs) in selective sweep regions of the genome of YMPs and present the genetic nsSNP distributions that are potentially associated with disease occurrence in humans. Methods: nsSNPs in whole genome resequencing data from 12 YMPs were identified and annotated to predict their possible effects on protein function. Sorting intolerant from tolerant (SIFT) and polymorphism phenotyping v2 analyses were used, and gene ontology (GO) network and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses were performed. Results: The results showed that 8,462 genes, encompassing 72,067 nsSNPs were identified, and 118 nsSNPs in 46 genes were predicted as deleterious. GO network analysis classified 13 genes into 5 GO terms (p<0.05) that were associated with kidney development and metabolic processes. Seven genes encompassing nsSNPs were classified into the term associated with Alzheimer's disease by referencing the genetic association database. The KEGG pathway analysis identified only one significantly enriched pathway (p<0.05), hsa04080: Neuroactive ligand-receptor interaction, among the transcripts. Conclusion: The number of deleterious nsSNPs in YMPs was identified and then these variants-containing genes in YMPs data were adopted as the putative human diseases-related genes. The results revealed that many genes encompassing nsSNPs in YMPs were related to the various human genes which are potentially associated with kidney development and metabolic processes as well as human disease occurrence.

• Biomedical Science Letters
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• 제27권2호
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• pp.99-104
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• 2021

Treatment techniques that affect homeostasis by non-invasive regulation in peripheral organs will advance disease research. Here, we demonstrate a non-invasive method of conditioning within an organ using a low-frequency stimulator superposition of alternating microcurrent wave in stages. It is first applied to the inflammatory response in H3N2-infected sinusitis mice. To check the progress of the treatment, mice were sacrificed every week for 3 weeks, nasal tissue was removed, and the inflammatory response was investigated through H & E staining. The low-frequency stimulation treatment group was found to alleviate the proliferation of epithelial cells and invasion of inflammatory cells compared to the control group as the passage of treatment time. The reduction of inflammatory cytokines in the nasal lavage fluid was observed in H3N2-infected sinusitis mice treated with of low-frequency stimulation using superposition of alternating microcurrent wave compared to H3N2-infected sinusitis mice after 3 weeks. These data demonstrate that low-frequency stimulation device in the form of using alternating current wave superposition on within organs provides a new method to regulate specific physiological functions. Therefore, it is necessary to prove the inhibitory effect of low-frequency stimulation using alternating current wave superposition on inflammatory diseases by various methods through further studies and clinical studies.

• Journal of Physiology & Pathology in Korean Medicine
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• 제35권1호
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• pp.15-21
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• 2021

Donggwaja (Benincasae Semen), the seed of Benincasa hispida (Thunb.) Cogn., has been used in Korean traditional medicine to control the body heat and water retention caused by various diseases. Both the symptoms targeted by the herbal medicine in clinic and studies with disease mouse models support the potential anti-inflammatory effect of Donggwaja. However, it is less understood how Donggwaja exerts its possible anti-inflammatory effect. Here, we present evidence that Donggwaja suppresses macrophage inflammatory reactions via expressing tumor necrosis factor a-induced protein 3 (TNFAIP3 or A20) and suppressing NF-kB activity. The ethanol extract of Donggwaja (EED) showed no toxicity when added to RAW 264.7 cells less than 100mg/ml. When treating the cells for 16 h, EED significantly suppressed the nuclear localization of NF-kB, suggesting that EED suppresses NF-kB activity. Concordantly, a semi-quantitative RT-PCR analysis showed that EED decreased the expression of prototypic pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-a, IL(interleukin)-6, and IL-1b. EED induced in RAW 264.7 cells the expression of A20, a ubiquitin modulator that suppresses inflammatory signaling cascades initiated from TLR4 and TNF and IL-1 receptors, while not affecting the induction of Nrf2, an anti-inflammatory factor that could suppress the effect of NF-kB. These results suggest that EED exerts its suppressive effect on inflammation, at least in part, by expressing anti-inflammatory factor A20 and suppressing pro-inflammatory factor NF-kB activity.