• The Korean Journal of Physiology and Pharmacology
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• v.12 no.2
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• pp.43-49
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• 2008

Flavonoids have been shown to affect calcium signaling in neurons. However, there are no reports on the effect of apigenin on glutamate-induced calcium signaling in neurons. We investigated whether apigenin affects glutamate-induced increase of free intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) in cultured rat hippocampal neurons, using fura-2-based digital calcium imaging and microfluorimetry. The hippocampal neurons were used between 10 and 13 days in culture from embryonic day 18 rats. Pretreatment of the cells with apigenin ($1{\mu}M$ to $100{\mu}M$) for 5 min inhibited glutamate ($100{\mu}M$, 1 min) induced $[Ca^{2+}]_i$ increase, concentration-dependently. Pretreatment with apigenin ($30{\mu}M$) for 5 min significantly decreased the $[Ca^{2+}]_i$ responses induced by two ionotropic glutamate receptor agonists, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA, $10{\mu}M$, 1 min) and N-methyl-D-aspartate (NMDA, $100{\mu}M$, 1 min), and significantly inhibited the AMPA-induced peak currents. Treatment with apigenin also significantly inhibited the $[Ca^{2+}]_i$ response induced by 50 mM KCl solution, decreased the $[Ca^{2+}]_i$ responses induced by the metabotropic glutamate receptor agonist, (S)-3,5-dihydroxy-phenylglycine (DHPG, 100 $[Ca^{2+}]_i$, 90 s), and inhibited the caffeine (10 mM, 2 min)-induced $[Ca^{2+}]_i$ responses. Furthermore, treatment with apigenin ($30{\mu}M$) significantly inhibited the amplitude and frequency of 0.1 mM $[Mg^{2+}]_o$-induced $[Ca^{2+}]_i$ spikes. These data together suggest that apigenin inhibits glutamate-induced calcium signaling in cultured rat hippocampal neurons.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.53-58
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• 1998

For evaluating the mutagenic potential of 2-carbomethoxy-4-chlorodiethyl phosphate, three different short-term mutagenicity tests were used; Salmonella typhimurium preincubation assay with and without rat liver microsomal activation, chromosome aberration test in cultured chinese hamster lung fibroblast cell and in vivo micronucleus test in male mice bone marrow. In Salmonella typhimurium reverse mutation assay using TA98, TA100, TAl535 and TAl537, 2-carbomethoxy-4-chlorodiethyl phosphate did not show any mutagenic response in the presence and absence of S9 mix. It did not induce any significant structural chromosome aberrations in the absence of metabolic activation. In micronucleus test using ICR mice, the frequency of micronucleated polychromatic erythrocytes (MNPCE) increased in bone marrow cells treated with positive control, mitomycin-C, but 2-carbomethoxy-4-chlorodiethyl phosphate did not increase micronucleated polychromatic erythrocytes. These results indicate that 2-carbomethoxy-4-chlorodiethyl phosphate does not show any positive responses in short-term genotoxicity assays.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.273-280
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• 1988

This study was undertaken to investigate the effect of the medial amygdaloid nucleus on the pancreatic exocrine secretion and plasma secretin concentration in 44 male albino rats. Twenty-three rats in which the medial amygdaloid nucleus was damaged bilaterally by radio frequency a.c. through stereotaxically inserted electrodes (medical amygdaloid group, MA) and twenty-one rats which received the same operation without damage (operated control, OC), were prepared. Under urethan anesthesia, 0.01 N hydrochloric acid (HCl) or physiological saline (0.9% NaCl) was infused at a rate of 0.18 ml/min into the duodenum for 20 minutes. Pancreatic jucie was collected for the 20 min infusion period. After collection of pancreatic juice, blood was sampled from the abdominal aorta for the radioimmunoassay of plasma secretin concentration. In the MA group, the exocrine pancreatic secretory response to 0.01 N HCI as well as saline infusion was significantly inhibited compared with that in the OC group. The pancreatic protein output of the MA group significantly decreased after the saline infusion and tended to decrease after the 0.01 N HCI infusion, compared with that of the OC group. However, there was no significant difference in plasma secretin concentration between the two groups. Therefore it is strongly suggested that the rat medial amygdaloid nucleus has a facilitatory influence on both basal and acid-stimulated pancreatic exocrine secretion, but the releasing mechanism of secretin appears not to be involved in the influence.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.532-542
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• 2018

Because maglev trains have a propulsion and absorption force without contact with the rails, they can drive safely at high-speed with little oscillation. Recently, test model of a maglev propulsion train was produced and operated, and has since been chosen as a national growth industry in South Korea; there have been many studies and considerable investment in these fields. This study examined the dynamic responses due to bridge-maglev train interaction and basic material to design bridges for maglev trains travelling at high-speed. Depending on the major factors affecting the dynamic effects, the scope of this study was restricted to the relationship between dynamic responses. A concrete box girder was chosen as a bridge model and injured train and rail types in domestic production were selected as the moving train load and guideway analysis model, respectively. From the analysis results, the natural frequency of a bridge for a maglev train, which has a deflection limit L/2000, was higher than those of bridges for general trains. The dynamic responses of the girder of the bridge for a maglev train showed a substantial increase in proportion to the velocities of the moving train like other general bridge cases. Maximum dynamic response of the girder is shown at a moving velocity of 240km/h and increased with increasing moving velocity of train. These results can be used to design a bridge for maglev propulsion trains and provide the basic data to confirm the validity and verification of the design code.

• Journal of Korean Library and Information Science Society
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• v.9
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• pp.241-266
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• 1982

This paper gives a summary and overview of a survey conducted at the catalogues of five universities in Daegu during November 1982. The major objective of this study was to secure information about user needs in order to improve the catalogue in Korean university libraries. Data was collected by a combined method of questionnaire and interview. A total of 379 respondents were taken on a randomly selected sample of catalogue users. Results of the survey can be summarized as follows: 1. Eighty-eight percent of the students answered that they had used the library more than twice a month. Nevertheless the number of students consulting the catalogue with the same frequency was only 220, or a n.0, pproximately 58 percent. Those who used the library most tended to use the catalogue more than those who rarely came to the library. 2. Those who had been shown how to use their own catalogue were only 32.5percent of which the students found the instruction sufficient for them to be able to use the catalogue were only 37.5 percent. In particular, they stated that instructions by printed materials and/or library orientation were so poor that they didn't give much help in using the catalogue. This problem makes many libraries to review their own method of instruction in order to encourage patrons to use the catalogue more effectively. 3. Most of the students consulted the catalogue in order to locate library materials. Known-item searches and subject searches were 84 and 16 percent respectively. While 70.5 percent of the students used the author-title catalogue without any difficulties, only 35.5 percent of those stated that using the classed catalogue was easy. 4. It was surprising that the number of students using title access in the search was far greater than that of students using author access. In contrast with this, other studies conducted by many earlier overseas investigators revealed that the great majority of patrons tended to use the latter first. Therefore, we should put more emphasis on the title entries in the catalogue itself as well as cataloging rules. 5. Most useful bibliographic elements in the entry were author, title, call number, date and publisher whereas edition, series statement and the location of publisher were rarely used compared with the other elements. Content note was the most desirable element in the entry to be involved, for many catalogers were used not to describe it on the note area. 6. The chief reason given for not using the catalogue was "I can manage without it" with "It's difficult to understand contents of the card entry." The other one was "It's useless to search materials by the catalogue because I've failed so many times to obtain them out of the stock." In response to this, circulation and acquisition system should be improved not to make such complaints any more.

• Journal of Korean Medical classics
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• v.22 no.4
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• pp.1-13
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• 2009

When feeling the pulse, healthy man' pulse is the criterion for diagnosis whether you are a sick person. Healthy man is defined as one who is harmonious and not sick in sympathy with natural order. Among the factors for being Healthy man, breathing and pulsation, Chon-gu(寸口) and Inyeong(人迎) are most closely connected with the representative methods of feeling the pulse which are used currently. According to "Hwangjenaegyeong(黃帝內經)" on breathing and pulsation, the pulse beats twice per a breathing-in and a breathing-out each. And for a specific breathing, it beats 5 times including the remnant with a big breath. That the pulse beats twice means that it beats not only twice, but also regularly and repeatedly. The remnant is related to the meaning on a leap month, 5-time beating during a breath is connected with the contents of Osipyeong(五十營). A human is not always in stable and sticks to balance continuously with changes under the circumstances. So when it comes to a criterion how to measure the pulsation frequency, breathing is much more reasonable than pulsation and breathing calculated for a minute. According to "Hwangjenaegyeong(黃帝內經)", Healthy man is the person of whose Chon-gu and Inyeong are in order and much the same in response to each other. Although there is a minor difference in the meaning of term between Chon-gu and Gigu(氣口), Maekgu(脈口) in originally, it is used as almost same meaning when Chon-gu is used in opposition to Inyeong. Afterwards, depending on medical men, around neck or Chon-gu of the left hand are measured for Inyeong. However, Inyeong described in "Naegyeong(內經)" is Jokyangmyeong(足陽明) and it means the Hyeol(穴) around neck where the pulse beats, it looks like about the carotid area. Chon-gu is fall under Eum(陰) and Inyeong(人迎) is fall under Yang(陽). Therefore Chon-gu is continuous with eumgyeong(陰經) and Inyeong is continuous with yanggyeong(陽經). In addition, the pulse and the four seasons meet each other and Inyeong is a little stronger in spring summer and Chongu is a little stronger in fall winter.

• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.703-711
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• 2018

Water distribution system (WDS) pipe bursts are caused from excessive pressure, pipe aging, and ground shift from temperature change and earthquake. Prompt detection of and response to the failure event help prevent large-scale service interruption and catastrophic sinkhole generation. To that end, this study proposes a improved Western Electric Company (WECO) method to improve the detection effectiveness and efficiency of the original WECO method. The original WECO method is an univariate Statistical Process Control (SPC) technique used for identifying any non-random patterns in system output data. The improved WECO method multiples a threshold modifier (w) to each threshold of WECO sub-rules in order to control the sensitivity of anomaly detection in a water distribution network of interest. The Austin network was used to demonstrated the proposed method in which normal random and abnormal pipe flow data were generated. The best w value was identified from a sensitivity analysis, and the impact of measurement frequency (dt = 5, 10, 15 min etc.) was also investigated. The proposed method was compared to the original WECO method with respect to detection probability, false alarm rate, and averaged detection time. Finally, this study provides a set of guidelines on the use of the WECO method for real-life WDS pipe burst detection.

• Journal of Oral Medicine and Pain
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• v.35 no.3
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• pp.213-219
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• 2010

Aim: The aims of this study were to survey the frequency of pain to palpation of the occipitofrontalis muscle in a TMD patient group, and to identify patients showing pain to palpation of the occipitofrontalis muscle that is also consistent with patients' headache symptom. Methods: A total of 218 TMD patients ($32.0{\pm}13.1$ years) participated in this study. Patients' symptoms, including headache, were surveyed by questionnaire. Temporomandibular joints, jaw muscles, and pericranial muscles including the occipitofrontalis muscle were examined with digital palpation. Pain to palpation (i.e. tenderness) was scored from 0 to 3 according to the patients' response, and frequencies were calculated of pain to palpation scores for each site of the pericranial muscles. Results: Twelve patients among 218 TMD patients (5.5%) showed pain to palpation (scores of 1, 2) on the occipitalis or frontalis sites, and seven patients (3.2%) had moderate pain (a score of 2) to palpation. Among 218 TMD patients, there was only one patient whose primary symptomatic site of headache corresponded with the result of pain to palpation of the occipitofrontalis muscle. Conclusion: It can be concluded that examination with palpation of the occipitofrontalis muscle could be considered in the evaluation of TMD patients' headache symptom when other factors have been ruled out.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.106-119
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• 2016

Flood risk map, flood damage map, disaster information map, inundation trace map are involved with the cartographic analysis of flood inundation based on prevention, preparation, restoration, response from natural disasters such as flood, flooding, etc. In this study, the analysis for channel and basin characteristics Chungju dam to Paldang dam of South han river after four river project. Flood scenario is selected to take advantage of design flood level of schematic design for river. Flood inundation of one dimensional non-uniform flow by using HEC-RAS with basin characteristics is accomplished and two dimensional unsteady flow was interpreted by using FLUMEN. Frequency analysis is carried out about each abundance of South han river for 100 year period, 200 year period and 500 year period. Flooding disaster area of 100 year period on 0.5m damage functions is 2378.8ha, 200 year period on 0.5m damage functions is 3155.2ha, 500 year period on 0.5m damage functions is 3995.3ha respectively. It will be significant data for decision making to establish inundation trace map for providing basic plan for river maintenance, land use plan, flood protection plan, application plan and getting information of flood expectation area.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.2
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• pp.293-303
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• 2002

Recently, the use of the high strength materials and development of construction techniques have resulted in more flexible and longer spanning in the stadium systems. So the natural frequency of stadium structures are became low. Stadium stand could be led to significant dynamic response as like resonance due to spectator rhythmical activities. The accurate analysis of dynamic behavior of stadium systems and the precise investigation of the dynamic loads on stadium structures are demanded for effective design. It is desirable to apply measured dynamic loads created by spectator activities because these dynamic loads are not easy to express numerical formula. As the floor mesh of stadium stand is refined, the number of divided elements increases in numerical analysis. the rise of the number of elements makes the numbers of nodal points increased and numerous computer memory required. So it is difficult to analysis refine full model of stadium structures by using the commercial programs. In this study, the various dynamic loads induced by spectator movements are measured and analyzed. And a new modeling method that reduce the nodal points are introduced. Vibration analysis of stadium stands is executed to inspect accuracy and efficiency of proposed method in this paper.