• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.287-298
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• 2013

Objectives: Workers who use chemicals are exposed to safety accidents and occupational diseases. Employers are required to provide workers with Material Safety Data Sheets (MSDSs) in order to prevent accidents and diseases related to chemicals. Thus, it is very important to offer reliable MSDSs. In this paper, we assessed the reliability of MSDSs for chemicals including formaldehyde. Methods: To evaluate MSDS reliability, we collected 14 MSDSs and bulk samples from the chemical industry. MSDS reliability was evaluated by the completeness of details. In order to evaluate the adequacy of the formaldehyde contents in a mixture, bulk samples were collected and analyzed by HPLC. The result of Globally Harmonized System (GHS) classification was confirmed by identifying physical chemical properties, toxicology information and ecological information. Results: The result of the evaluation of 14 MSDSs showed 76.29% average reliability on each item, especially 53.9% average appropriate rate on hazard risk classification. No chemicals failed to match between the content (%) in MSDSs and the result of analysis. Conclusions: To elevate MSDSs reliability, the certified education of MSDS drafters and reorganization of the MSDS circulation system is required.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.1
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• pp.40-48
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• 2011

This study was intended to resolve problems caused by different classification criteria and management methods of carcinogenicity, which have made industrial safety & health institutions and business employers difficult to execute projects or to carry out occupational safety and health related works, and have affected how civic groups perceive carcinogens. The content of this study contained the comparison of management and categorization standards for carcinogens between Korea and other countries as well as the current carcinogenicity-related information supply status of each professional institution. Furthermore, this research examined the current state of supplying information on carcinogenicity among major institutional information supply according to the categorization standard for carcinogens by UN GHS, Ministry of Employment and Labor in Korea(KMoEL), and GHS MSDS provided by Korea Occupational Safety & Health Agency(KOSHA). Now, professional agency provide 927 kinds of IARC, 237 kinds of NTP, 351 kinds of ACGIH and 1,006 kinds of EU ECHA information on carcinogenic agents. KMoEL provides carcinogenicity-related information of 58 chemical agents in accordance with the category of carcinogens guided by ACGIH. KOSHA offers 13,232 kinds of GHS MSDS information including 2,484 carcinogenic substances. Therefore, carcinogenicity-related information of chemical substances, which are not available on the existing GHS MSDS DB, should be updated for the future reference.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4313-4318
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• 2016

Background: This study documented the performance of providers of visual inspection with acetic acid (VIA) at primary health centers, assessing their compliance with the VIA skills checklist and determinants of non-compliance, and exploring their perceptions of VIA training sessions. Materials and Methods: A cross-sectional study was conducted among VIA providers in the $Mekn\grave{e}s$-Tafilalet region of Morocco. Structured observation of their performance was conducted through supervisory visits and multiple focus group discussions (FGDs). Results: Performance of all the recommended steps for effective communication was observed in a low proportion of procedures (36.4%). Midwives/nurses had higher compliance than general practitioners (GPs) (p<0.001). All recommended steps for VIA examination were performed for a high proportion of procedures (82.5%). Compliance was higher among midwives/nurses than among GPs (p<0.001) and among providers in rural areas than those in urban areas (p<0.001). For pre-VIA counselling, all recommended steps were performed for only 36.8% of procedures. For post-VIA counseling, all recommended steps were performed in a high proportion (85.5% for VIA-negative and 85.1% for VIA-positive women). Midwives/nurses had higher compliance than GPs when advising VIA-positive women (p=0.009). All infection prevention practices were followed for only 14.2% of procedures, and compliance was higher among providers in rural areas than those in urban areas (p<0.001). Most FGD participants were satisfied with the content of VIA training sessions. However, they suggested periodic refresher training and supportive supervision. Conclusions: Quality assurance of a cervical cancer screening program is a key element to ensure that the providers perform VIA correctly and confidently.

• Food Science of Animal Resources
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• v.42 no.4
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• pp.557-565
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• 2022

The purpose of this research was to examine the effectiveness of pre-cooking treatments on the quality characteristics of ready-to-eat (RTE) empal gentong. Raw beef meat was pre-cooked in water bath at 90℃ for 0 min (C), 10 min (T1), 20 min (T2), and 30 min (T3) prior to retorting process at 121℃ and pressure at 70,000 Pa. Results showed that pre-cooking treatments in all treated samples could reduce fat contents in empal gentong's meat by 0.02% (T1), 0.28% (T2), and 1.13% (T3) respectively. Highest precooking time tends to increase the pH and CIE a^* values. However, CIE b^* values, water holding capacity, and sensory analysis were not affected by pre-cooking duration which must have been affected by sterilization process after pre-cooking. In conclusion, pre-cooking treatment before sterilization in producing empal gentong is a probable technique to reduce its fat content and improve its physical quality. A specific treatment at 90℃ for 10 min is recommended to achieve optimum quality of RTE empal gentong's meat.

• Animal Bioscience
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• v.37 no.1
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• pp.61-73
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• 2024

Objective: The main objective of this study was to define molecular mechanisms associated with thermal stress responses of chickens from commercial broilers (BR, Ross 308), Thai native chickens (NT) and crossbreeds between BR×NT (H75). Methods: Twenty days before reaching specific market age, chickens from each breed were divided into control and thermal-stressed groups. The stressed groups were exposed to a cyclic thermal challenge (35℃±1℃ for 6 h, followed by 26℃±1℃ for 18 h) for 20 days. Control group was raised under a constant temperature of 26℃±1℃. Pectoralis major (n = 4) from each group was collected for transcriptome analysis using HiSeq Illumina and analysis of glycogen and lactate. Gene expression patterns between control and thermal-stressed groups were compared within the same breeds. Results: Differentially expressed transcripts of 65, 59, and 246 transcripts for BR, NT, and H75, respectively, were revealed by RNA-Seq and recognized by Kyoto encyclopedia of genes and genomes database. Pathway analysis underlined altered glucose homeostasis and protein metabolisms in all breeds. The signals centered around phosphatidylinositol 3-kinase (PI3K)/Akt signaling, focal adhesion, and MAPK signaling in all breeds with slight differences in molecular signal transduction patterns among the breeds. An extensive apoptosis was underlined for BR. Roles of AMPK, MAPK signaling and regulation of actin cytoskeleton in adaptive response were suggested for H75 and NT chickens. Lower glycogen content was observed in the breast muscles of BR and NT (p<0.01) compared to their control counterparts. Only BR muscle exhibited increased lactate (p<0.01) upon exposure to the stress. Conclusion: The results provided a better comprehension regarding the associated biological pathways in response to the cyclic thermal stress in each breed and in chickens with different growth rates.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1630-1634
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• 2011

Electroless plating of metallic nickel on carbon fiber surfaces was carried out to control specific electric resistivity of the fibers, and the effects of the nickel content and coating thickness on the electric properties were studied. The structural and surface properties of the carbon fibers were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The specific resistivity of the fibers was measured using a four-point probe testing method. From the XPS results, the oxygen and Ni atomic ratio of the fibers was greatly enhanced as the plating time increased. Additionally, it was observed that the specific electric resistivity decreased considerably in the presence of metallic nickel particles and with the formation of nickel layers on carbon fibers.

• Journal of the Korean Society for Heat Treatment
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• v.8 no.4
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• pp.266-278
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• 1995

The high strain-rate dynamic plastic behavior of Fe-X%Mn alloys was investigated. The strain rate did not have an effect when tested under quasi-static strain rates($2{\times}10^{-3}/sec$ and $2{\times}10^{-1}/sec$). However, the true stress increased at all strain levels when the strain rate increased to $6{\times}10^3/sec$. Based on the experimental results, an constitution equation to calculate the dynamic strength for strain rates over $10^4/sec$ was determined. The Fe-5%Mn alloy containing athermal ${\alpha}^{\prime}$ martensite initially did not show work hardening. The work hardening increased with Mn content showing a maximum at 20% Mn. The high work hardening of Fe-20%Mn and Fe-30%Mn alloys appears to be closely related not only to the initial amounts of ${\varepsilon}$ martensite but to the strain induced transformation (${\gamma}{\rightarrow}{\varepsilon}$ and ${\varepsilon}{\rightarrow}{\alpha}^{\prime}$) occurring during each stages of deformation.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.447-451
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• 2021

In this study, we discovered for the first time that linarin, a flavonoid compound, enhances melanin biosynthesis in B16F10 cells, and subsequently elucidated the underlying mechanism of linarin-induced melanogenesis. Linarin showed no cytotoxicity at a concentration of 42 μM and significantly increased intracellular tyrosinase activity and melanin content in B16F10 cells. Mechanistic analysis showed that linarin increased the expression of tyrosinase, tyrosinase-related protein 1 (TRP-1), and microphthalmia-associated transcription factor (MITF) that are related to melanogenesis. Moreover, linarin decreased the phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (AKT). Finally, we evaluated the effect of the structure-activity relationship of linarin and its aglycone on melanogenesis. The results indicated that linarin enhances the expression of melanogenic proteins by activating MITF expression via the modulation of mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K), and protein kinase B signaling pathways in B16F10 cells, thereby enhancing melanogenesis.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.495-500
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• 2020

VANET (Vehicular Ad Hoc Network), an example of an ad hoc vehicular networks, becomes one of the popular research areas together with the self-driving cars and the connected cars. In terms of the VANET implementation, the traditional TCP/IP protocol stack could be applied to VANET. Recently, CCN (Content Centric Networking) shows better possibility to apply to VANET, called VCCN (VANET over CCN). CCN maintains several data tables including CS (Content Store) which keeps track of the currently requested content segments. When the CS becomes full and new content should be stored in CS, a replacement algorithm is needed. This paper compares and contrasts four replacement algorithms. In addition, it analyzes the transmission characteristics in diverse network conditions. According to the simulation results, LRU replacement algorithm shows better performances than the remaining three algorithms. In addition, even the size of CS is small, the network maintains a reasonable transmission performance. As the CS size becomes larger, the transmission rate increases proportionally. The transmission performance decreases when the network is crowded as well as the number of transmission hops becomes large.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.552-557
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• 1996

Gels of rice starches isolated from jinmibyeo, llpoombyeo and Dongjinbyeo were prepared with $60{\sim}65%$ water content (based on the total weight) and stored at $-18^{\circ}C,\;4^{\circ}C,\;20^{\circ}C,\;30^{\circ}C,\;and\;37^{\circ}C$ for 6 days. The effects of varieties, water content and storage temperature on the degree of retrogradation (DR) of gels were measured by ${\alpha}$-amylase-iodine method. DRs of rice starch gels increased rapidly during the initial stage of storage, but slowly after that. DRs were highest with 60% water content and lowest with 65% water content at any storage temperature. Regarding the storage temperature, DRs of gels increased in the following order : $4^{\circ}C>20^{\circ}C>30^{\circ}C>37^{\circ}C>-18^{\circ}C>$. As the storage temperature was increased, DR per $10^{\circ}C$ increased above refrigerated temperature decreased in the following order : jinmibyeo>llpoombyeo>Dongjinbyeo.