• 대한수의학회지
• /
• 제34권3호
• /
• pp.619-626
• /
• 1994

The purpose of present study was to examine pharmacological effect of Artemisia Iwayomogi methanol extract(AIME) on biochemical parameters(activities of AST, ALT, LDH, and ALP, contents of total bilirubin, total protein, albumin and A/G ratio in serum and levels of hepatic microsomal lipid peroxide and glucose-6-phosphatase activities) against hepatic injury by carbon tetrachloride($CCl_4$) in rats. Increased AST, ALT and LDH activities by $CCl_4$ were decreased in AIMS treatment group at 48 or 72 hours. Together, increased ALP activity by $CCl_4$ almost returned toward normal value in AIME treatment group at 72 hours. Serum total bilirubin contents increased to 87, 79 and 31% compared with normal group by $CCl_4$ which were decreased to 64, 42 and 26% in AIME treatment group at 24, 48 and 72 hours, respectively. Decreased contents of total protein and albumin, and A/G ratio by $CCl_4$ were recovered in AIME treatment group. Hepatic microsomal lipid peroxide levels(nmol malonic dialdehyde/100mg protein) increased to 140, 95 and 78% compared with normal group by $CCl_4$ which were decreased to 107, 74 and 65% in AIME treatment group at 24, 48 and 72 hours, separately. Hepatic microsomal glucose-6-phosphatase activities decreased to 60, 50 and 53% compared with normal group by $CCl_4$ at 24, 48 and 72 hours, respectively, which were increased at 72 hours in AIME treatment group. In conclusion, AIME enhanced the amelioration process from $CCl_4$-induced lipid peroxidation, degeneration of liver cell, and impairment of protein and bilirubin metabolisms.

• 한국안전학회지
• /
• 제38권5호
• /
• pp.58-64
• /
• 2023

This study aims to analyze the differences between the safety leadership of the laboratory director, safety climate, safety motivation, and safety behavior of research workers based on whether they have participated in the certification system for exemplary laboratories in safety management (CSEL). An online survey was conducted among research workers to analyze the effect of the CSEL. The independent variables used in the survey were participation and non-participation in the CSEL, while the dependent variables were the safety leadership of the laboratory director, safety climate, safety motivation, and safety behavior of research workers. The results demonstrate that the group that participated in the CSEL had statistically significantly higher levels of safety leadership, safety climate, safety motivation, and safety behavior than the one that did not do so. Therefore, it can be concluded that the CSEL has a positive impact on the establishment of an autonomous safety management system in a laboratory by improving the safety culture and safety behavior of research workers. Further, the extrinsic factors, which are subfactors for safety motivation, did not reflect a significant difference between the group that participated in the CSEL and the one that did not. Thus, a reward system for research workers with excellent safety activities should be operated by research institutes since it is necessary to strengthen the intrinsic safety motivation of individual research workers which can be strengthened by compensation. The government should consider measures such as providing research incentives to researchers participated in CSEL.

• 한국융합학회논문지
• /
• 제10권12호
• /
• pp.159-168
• /
• 2019

이 연구는 한국인의 비타민 D 수준에 관련된 요인들을 조사 후 인과 관계를 알아보는 것을 목적으로 하였다. 연구 자료로 국민건강영양조사 제6기 2014년도에서 연구요인을 가진 1,977명을 대상으로 하였다. 혈청 Vitamin D와 관련된 요인들을 찾기 위하여 교차 분석을 하였고, 통제변수 통제 로지스틱 회귀분석으로 상대위험도를 평가하였다. 남성은 40세 미만(OR 4.1), 봄·겨울(OR 4.2, 도시거주(OR 2.1), 흡연자(OR 1.8), 보충제 미복용(OR 2.1), 긴 좌식생활 시간일수록 위험도가 높았다(OR 1.1). 여성은 40세 미만(OR 1.9), 실내직종(OR 4.5), 보충제 미복용(OR 3.0)의 비교 위험도가 유의하게 높아 남성과 다르게 관찰되었다. 성별 비교위험도가 다르게 관찰된 이유로 성별에 따른 건강행위의 차이로 판단된다. 연구 결과 한국인의 Vitamin D 는 결핍으로 관찰되었으며, 주요한 중재수단으로 Vitamin D가 함유된 보충제의 복용과 야외활동을 늘려야 할 것으로 판단된다. 한국인의 질병예방에 기초자료로 이용과 향후 실험연구가 진행될 것으로 기대된다.

• Advances in concrete construction
• /
• 제10권3호
• /
• pp.221-236
• /
• 2020

To reduce the CO₂ emissions associated with the manufacture of portland cement (PC), an efficient alternative like an alkali-activated binder (AAB) is the requirement of the industry. To promote the use of AAB in construction activities, a practically implementable mix proportion is required. Owing to the several raw ingredients of AAB concrete and their associated uncertainties, partial replacement of PC by AAB may be adopted instead of complete replacement as per industrial requirements. Hence, the present study aims to determine an optimal proportion for partial replacement of PC with AAB and recommend a technique for it based on site conditions. Three modes of partial replacement are followed: combining all the dry ingredients for AAB and PC followed by the addition of the requisite liquids (PAM); combining the PC and the AAB concrete in two horizontal layers (PAH); and two vertical layers (PAV). 28-day old specimens are exposed to 10% v/v solutions of HCl, H₂SO₄, and HNO₃ to evaluate changes in mechanical, physical, and microstructural characteristics through compressive strength, corrosion depth, and microscopy. Based on deterioration in strength and integrity, PAH or PAV can be adopted in absence of acid attack, whereas PAM is recommended in presence of acid attack.

• ETRI Journal
• /
• 제36권5호
• /
• pp.819-828
• /
• 2014

To solve the increasing popularity of video streaming services over the Internet, recent research activities have addressed the locality of content delivery from a network edge by introducing a storage module into a router. To employ in-network caching and persistent request routing, this paper introduces a hybrid content delivery network (CDN) system combining novel content routers in an underlay together with a traditional CDN server in an overlay. This system first selects the most suitable delivery scheme (that is, multicast or broadcast) for the content in question and then allocates an appropriate number of channels based on a consideration of the content's popularity. The proposed scheme aims to minimize traffic volume and achieve optimal delivery cost, since the most popular content is delivered through broadcast channels and the least popular through multicast channels. The performance of the adaptive scheme is clearly evaluated and compared against both the multicast and broadcast schemes in terms of the optimal in-network caching size and number of unicast channels in a content router to observe the significant impact of our proposed scheme.

• International Journal of Computer Science & Network Security
• /
• 제22권6호
• /
• pp.109-114
• /
• 2022

The article is devoted to analyzing the police influence on road safety formation. The globalization processes confirm the study's relevance, provoking population mobility and the need to increase freight traffic. The study aims to identify the factors that affect road safety and the activities of the police and the EU transport safety units. An empirical analysis using factor analysis, correlation analysis, and general scientific methods of cognition were carried out to achieve the goal. The analysis results found that the number of police officers affects road safety, but not in all countries, which confirms the importance of other factors. Based on the analysis results of the scientific literature, the factors affecting transport safety are legislative regulation, the use of innovative technologies, transport infrastructure, geography, and psycho-physical and emotional drivers factors. It has been proved that the police authorities and units cannot fully ensure transport safety in the European Union because the safety is formed by a complex of actions by the state and road users.

• 대한치과기공학회지
• /
• 제23권2호
• /
• pp.121-149
• /
• 2002

This Study aims at investigating the tendency of individual problems that the students at the departments of dental technology are faced with, their efforts and types of activities to solve the problems. Surveyed for this purpose were 700 freshmen to juniors enrolled in the departments of dental technology at the universities across the country and they were analyzed by area, grade and sex. 1. Tendency of Problems The areas of problems the students at the departments of dental technology considered as most serious were health, human relation, view of value and economy in sequence, while the areas they considered as least serious were future course and employment. In general, there were tendencies as follows: divided by grade, the higher the grades of the students are, the higher scores of problems they get(F=12.14, P=.000) : in the areas of health and human relation, as the grade gets higher, the scores of their problems also increase, accordingly(F= 17.58, P=.000)(F=8.39, P=.000) : in the areas of economy, parents and home, freshmen and juniors are found to have higher scores of problems compared to sophomores,:F=7.89, P=.000)(F=11.63, P=.000) : divided by sex, female students recorded higher scores of problems than their counterparts(F=31.85, P=.000) 2. Efforts for Problems View of value, human relation, parents and home appeared to be the areas for which the students made the highest rate of efforts in sequence while the areas for which they paid lowest grade of efforts were health and economy. In other words, the students gave higher scores for human relation and view of value in terms of tendency as well as efforts of problems, while they rated high for health and economy in the tendency but low in the efforts of problems. Divided by grade, freshmen and juniors appeared to score higher points than sophomores in their efforts to solve problems, even though juniors made relatively higher efforts than freshmen(F=6.53, P=.002). Divided by sex, female students scored higher points in their efforts than males(F=15.98, P=.000) 3. Difference of Efforts to Solve Problems. In the analysis into the scores of difference showing the disagreement between the tendency of problems and the efforts to solve problems, the area of health was rated as highest, followed by economy. There was little difference of scores between human relation and view of value, an indicator of agreement between the scores of problems and efforts. The difference of scores between future course and employment, between liberal arts and recreation, between characters/parents and home/school work turned out to be negative in the listed sequence, leading to a conclusion that the students enrolled in the departments of dental technology are making more efforts to solve problems than actually needed in most areas. By grade, there was a significant difference only in the area of health(F=3.00, P=.050). This difference itself was widening as the students come to higher grades. By sex, females showed bigger difference than males. 4. Types of Activities to Solve Problems. The analysis into types of activities to solve problems revealed that the surveyed students seemed to actively cope with the problems in all areas, relying at the same time on personal relationship. Especially in the areas of health, economy, parents, home, human relation, future course and employment, the students appeared to deal with the problems actively as well as emotionally.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권5호
• /
• pp.1833-1837
• /
• 2015

An aristolactam-type alkaloid, isolated from Orophea enterocarpa, is enterocarpam-III (10-amino-2,3,4,6-tetramethoxyphenanthrene-1-carboxylic acid lactam). It is cytotoxic to various human and murine cancer cell lines; however, the molecular mechanisms remain unclear. The aims of this study were to investigate cytotoxic effects on and mechanism (s) of human cancer cell death in human hepatocellular carcinoma HepG2 and human invasive breast cancer MDA-MB-231 cells compared to normal murine fibroblast NIH3T3 cells. Cell viability was determined by MTT assay to determine $IC_{10}$, $IC_{20}$ and $IC_{50}$ levels, reactive oxygen species (ROS) production with 2',7'-dichlorohydrofluorescein diacetate and the caspase-3, -8 and -9 activities using specific chromogenic (p-nitroaniline) tetrapeptide substrates, viz., DEVD-NA, IETD-NA and LEHD-NA and employing a microplate reader. Mitochondrial transmembrane potential (MTP) was measured by staining with 3, 3'-dihexyloxacarbocyanine iodide ($DiOC_6$) and using flow cytometry. The compound was cytotoxic to HepG2 and MDA-MB-231 cells with the $IC_{50}$ levels of $26.0{\pm}4.45$ and $51.3{\pm}2.05{\mu}M$, respectively. For murine normal fibroblast NIH3T3 cells, the $IC_{50}$ concentration was $81.3{\pm}10.1{\mu}M$. ROS production was reduced in a dose-response manner in HepG2 cells. The caspase-9 and -3 activities increased in a concentration-dependent manner, whereas caspase-8 activity did not alter, indicating the intrinsic pathway activation. Enterocarpam-III decreased the mitochondrial transmembrane potential (MTP) dose-dependently in HepG2 cells, suggesting that the compound induced HepG2 cell apoptosis via the mitochondrial pathway. In conclusion, enterocarpam-III inhibited HepG2 and MDA-MB-231 cell proliferation and induced human HepG2 cells to undergo apoptosis via the intrinsic (mitochondrial) pathway and induction of caspase-9 activity.

• 한국학교ㆍ지역보건교육학회지
• /
• 제22권4호
• /
• pp.49-60
• /
• 2021

Objectives: Laboratories have various latent physical, chemical, biological, and ergonomical factors according to the diversification and fusion of research and development activities. This study aims to investigate the chemical exposure concentrations of college laboratories and evaluate their health risks, and use them as basic data to promote the health of college students. Methods: The sampling and analysis of harmful chemicals in the air in laboratories were performed using Method 1500 of the U.S. National Institute for Occupational Safety and Health (NIOSH)의 Method 1500. The harmful chemicals in the laboratories were divided into carcinogenic and non-carcinogenic chemicals. Risk assessment was performed using the cancer risk (CR) for carcinogenic chemicals and using the hazard index (HI) for non-carcinogenic chemicals. Results: The harmful chemicals in college laboratories consisted of acetone, diethyl ether, methylene chloride, n-hexane, ethyl acetate, chloroform, tetrahydrofuran, toluene, and xylenes. They showed the highest concentrations in laboratories A (acetone 0.001~2.34ppm), B (chloroform 0.95~6.35ppm), C (diethyl ether 0.08~8.68ppm), and D (acetone 0.07~14.96ppm). The risk assessment result for non-carcinogenic chemicals showed that the HI of methylene chloride was 2.052 for men and 2.333 for women, the HI of N-hexane was 4.442 for men and 5.05 for women. Thus, the HI values were higher than 1. The risk of carcinogenic chemicals is determined by an excess cancer risk (ECR) value of 1.0×10^-5, which means that one in 100,000 people has a cancer risk. The ECRs of chloroform exceeded 1.0×10^-5 for both men and women, indicating the possibility of cancer risk. Conclusion: College laboratories showed the possibility of non-carcinogenic health risks for methylene chloride, n-hexane, tetrahydrofuran (THF), toluene, and xylenes, and carcinogenic health risks for chloroform, methylene chloride. However, this study used the maximum values of measurements to determine the worst case, and assumed that the subjects were exposed to the corresponding concentrations continuously for 8 hours per day for 300 days per year. In consideration of the nature of laboratory environment in which people are intermittently exposed, rather than continuously, to the chemicals, the results of this study has an element of overestimation.

• 대한인간공학회지
• /
• 제30권6호
• /
• pp.765-773
• /
• 2011

Objective: This study aims towards exploring a model of the HCI evaluation methods to improve the usability of mobile device, based on a case of a Mobile PDA system in a Museum context. Background: Mobile PDA systems in a Museum context is widely utilized for the educational purposes, but it is criticized for low usability that the device only play a role in textbooks on legs without any interactive educational activities. Therefore, the usability improvements on the mobile PDA system should be considered. Method 1: This model was developed with a combination of the expert review and the user testing, and with a combination of the qualitative and quantitative studies. In more details, first of all, a qualitative study was conducted as a combination of three different methods: 1) expert review with heuristics, 2) interviews with persons working in a museum, and 3) contextual enquiry. Results 1: The experts review provided with critical usability issues, and the semi-constructive interview helped to understand the background of the mobile device. Lastly, the contextual enquiry showed user experience problems and directions of improving the device from user's perspective. Method 2: Based on the results of the qualitative study, a questionnaire was designed. Results 2: The analysis of the quantitative study was conducted to generalize the problems, and prioritize the direction of improving the device within the limitation of the cost and time in a museum. Conclusion: This study has implications in developing an example of a HCI evaluation model to improve the user experience of the mobile device as well as finding problems and directions of how to improve the mobile PDA systems in the museum. Application: In fact, most of the studies related to the evaluation of the mobile device have been conducted in a laboratory context due to the cost and time. This paper, however, attempted to apply to various HCI research techniques from different constituents in real context.