• Journal of Ginseng Research
• /
• v.45 no.5
• /
• pp.539-545
• /
• 2021

Background: Red ginseng polysaccharides (RGPs) have been acknowledged for their outstanding immunomodulation and anti-tumor activities. However, their studies are still limited by the complexity of their structural features, the absence of purification and enrichment methods, and the rarity of the analytical instruments that apply to the analysis of such macromolecules. Thus, this study is an attempt to establish a new mass spectrometry (MS)-based analysis procedure for RGPs. Methods: Saponin pre-excluded powder of RG (RG-SPEP, 10 mg) was treated with 200 µL of distilled water and centrifuged for 5 h at 1000 rpm and 85 ℃. Ethanol-based precipitation and centrifugation were applied to obtain RGPs from the heated extracts. Further, endo-carbohydrase treatments were performed to produce specific saccharide fragments. Solid-phase extraction (SPE) processes were implemented to purify and enrich the enzyme-treated RGPs, while matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) MS was employed for the partial structural analysis of the obtained RGPs. Results: Utilizing cellulase, porous graphitized carbon (PGC), hydrophilic interaction chromatography (HILIC), and MALDI-TOF/TOF MS, the neutral and acidic RGPs were qualitatively analyzed. Hex_n and Hex_n-18 (cellulose analogs) were determined to be novel neutral RGPs. Additionally, the [Unknown + Hex_n] species were also determined as new acidic RGPs. Furthermore, HexA_n (H) was determined as another form of the acidic RGPs. Conclusion: Compared to the previous methods of analysis, these unprecedented applications of HILIC-SPE and MALDI-TOF/TOF MS to analyze RGPs proved to be fairly effective for fractionating and detecting neutral and acidic components. This new procedure exhibits great potential as a specific tool for searching and determining various polysaccharides in many herbal medicines.

• Korean journal of applied entomology
• /
• v.39 no.3
• /
• pp.153-156
• /
• 2000

Spatial activities of Liriomyza trifolii (Burgess) were investigated weekly using yellow sticky trap which were placed at three different height and monitored during four time periods. Yellow sticky trap placed at plant height caught significantly more L. trifolii (Burgess) than did traps placed at 30 and 60cm above plant height. Diel activities of L. trifolii (Burgess) were monitored with yellow sticky traps at 1- and 2-h intervals during three time periods. Leafminer flight activity in May, July and October peaked from 1400 to 1800 hours, 0800 hours and from 1200 to 1400 hours, respectively. 2nd peak of flight activity only occurred in May. Attraction of L. trifolii (Burgess) for yellow sticky traps was affected by temperature as well as solar intensity. Male of L. trifolii (Burgess) appeared more responsive to yellow sticky traps than female regardless of trap height or time of day.

• Journal of the Korean housing association
• /
• v.14 no.5
• /
• pp.117-128
• /
• 2003

The purpose of this study is to investigate the effect of functional ability on relocation among the elderly. Longitudinal data from the Asset and Health Dynamics among the Oldest Old (1993, 1995) were analyzed for 6,225 respondents aged 70 or older. Among functional ability measures, difficulties in advanced activities of daily living (i. e., making telephone calls, taking medications, and managing money), lower body activities (i. e., walking several blocks, climbing one flight of stairs, pulling or pushing large objects, and carrying over 10 pounds), and household activities of daily living (i. e., preparing hot meals and shopping for groceries) were the predictors of increased residential move. Difficulties in basic activities of daily living (i. e., bathing, dressing, getting in and out, and using the toilet) were strongly related to increased entrance into an institutional care facility. Efforts to enhance the independent living of the elderly in the community setting should target the compensation of these functional difficulties.

• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• v.5 no.2
• /
• pp.37-42
• /
• 2024

This study used a GPS tracker to determine characteristics of wintering habitat use by black-tailed gulls on the west coast of Korea. Results of this study showed a southward movement in December and a northward movement in March. The wintering habitat was confirmed to include the southwest coastal island area (Group 1), the inland coastal area (Group 2), and China (Group 3). The wintering home range was the narrowest in October and the widest in December. Home range of Group 1 was increased from November, showing the maximum in December, decreased in February, and then tended to increase again in March. Group 2 showed the widest home range in November and a narrow range of home range from December. Home range of Group 3 showed a mixed pattern of group 1 and group 2. The flight rate was the lowest in January and the highest in March. Day and night flight rates showed significant differences by month. This study identified wintering characteristics of the West Coast population of black-tailed gulls on the West Coast, including their wintering areas, migration periods, and use patterns. These wintering characteristics of black-tailed gull in the west coast area are thought to be affected by environmental factors (such as food resources and fishing activities) and geographical characteristics of the West Coast where many islands are distributed.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.9 no.3
• /
• pp.20-24
• /
• 2006

In this paper, our research efforts and activities for displaying flight simulation graphics on multi-monitors connected to a Linux cluster is introduced. In this pilot system graphics rendering as well as view calculation including LOD implementation for each monitor is peformed on each sub-node computer connected to the monitor rather than using an expensive main server. The Linux cluster is constructed by combining general-purpose desktop computers, and MPI library Is used for communication between sub-nodes. It could be concluded from our experience that it is possible to construct a massive multi-monitor display system by adding to the cluster as many sub-node computers and monitors as possible with economic efficiency.

• Journal of Ginseng Research
• /
• v.43 no.4
• /
• pp.539-549
• /
• 2019

Background: 20(S)-Protopanaxadiol (PPD), the aglycone part of 20(S)-protopanaxadiol ginsenosides, possesses antidepressant activity among many other pharmacological activities. It is currently undergoing clinical trial in China as an antidepressant. Methods: In this study, an ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass tandem mass spectrometry method was established to identify the metabolites of PPD in human plasma and urine following oral administration in phase IIa clinical trial. Results: A total of 40 metabolites in human plasma and urine were identified using this method. Four metabolites identified were isolated from rat feces, and two of them were analyzed by NMR to elucidate the exact structures. The structures of isolated compounds were confirmed as (20S,24S)-epoxydammarane-12,23,25-triol-3-one and (20S,24S)-epoxydammarane-3,12,23,25-tetrol. Both compounds were found as metabolites in human for the first time. Upon comparing our findings with the findings of the in vitro study of PPD metabolism in human liver microsomes and human hepatocytes, metabolites with m/z 475.3783 and phase II metabolites were not found in our study whereas metabolites with m/z 505.3530, 523.3641, and 525.3788 were exclusively detected in our experiments. Conclusion: The metabolites identified using ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass spectrometry in our study were mostly hydroxylated metabolites. This indicated that PPD was metabolized in human body mainly through phase I hepatic metabolism. The main metabolites are in 20,24-oxide form with multiple hydroxylation sites. Finally, the metabolic pathways of PPD in vivo (human) were proposed based on structural analysis.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2007.11a
• /
• pp.27-37
• /
• 2007

Many problems related to airline business belong to large-scale optimization problems, so that it is expected that the state-of-art optimization techniques are widely applied to making the airline operation effective and competitive. This paper introduces the concepts and mathematical models of various optimization problems in airline system. Airlines involve many activities that utilize airline resources such as aircrafts and crews to make profit. We view the airline activities in the planning and operational aspects. In the planning viewpoint, we discuss the flight schedule design problem that impacts on passenger demand directly. For aircraft and crews, we deal with fleet assignment, aircraft routing, crew pairing optimization, and crew assignment problem. In the operational viewpoint, we concern schedule recovery problems for aircrafts and crew using the method of reassigning available resources when airlines face with the unexpected situations.

• Journal of Environmental Science International
• /
• v.29 no.8
• /
• pp.809-818
• /
• 2020

To conserve the population of a hesperiid butterfly, Leptalina unicolor, inhabiting the protected areas of Jaeyaksan, we provide ecological information on their behavior and propose habitat conservation measures, such as the creation of alternative habitats based on comprehensive information. The behavioral study used a method of re-capture after releasing the butterfly with enamel marks on the wings. Adult behaviors were shown in four patterns: flying, settling on a plant, nectar absorption, and water absorption. Both males and females had the highest proportion of flight movement overall; however, males had a slightly higher proportion of flight movement. As for duration, females spent more time settling on plants to select spawning sites, and males seemed to take a longer time for water absorption activities, to absorb minerals needed to form the spermatophore. The average travel distance of butterflies was 27.5 m for females and 46.7 m for males, with daily activity ranges from 11.2 m to 43.8 m, and 21.4 to 57.6 m, respectively. The most important condition to preserve the habitat of Leptalina unicolor is to maintain the community of Miscanthus sinensis, a food plant. Additionally, because this butterfly has a high rate of water absorption activities, wetlands should be maintained.

• Biomedical Science Letters
• /
• v.6 no.4
• /
• pp.269-279
• /
• 2000

This present study was investigated to elucidate degenerative changes according to the change of habitual environment on the myocytes of doves by restricting them from flight that is instinct behavior of this animal and strong exercise. To restrict doves from flight, they were confined in the cage (1 $m^3$) for 2 months. After this period, the myocardium of the experimental group was compared to that of wild doves in the ultrastructural and cytochemical ways. In addition, stereological changes were also examined. The results were as followings: 1. The body weight of the confined experimental groups was higher than that of the wild doves, but the ratios of the pectoral muscle/body weight (p<0.05) and the heart/body weight were lower. 2. At the ultrastructural level, the myocardium of confined doves appeared as wavy fibers in the smaller area than in the myocardium of wild doves. Also, the length of sarcomeres was longer in the confined doves. The number of sarcoplasmic reticulum and capillary was smaller in the myocardium of confined doves. 3. Cytochemical examinations showed that the activities of cytochrome oxidase were lowered in the confined doves. 4. Stereological analysis revealed that the density of myofibrils was greater in the confined doves. In contrast the volume density of sarcoplasmic reticulum (p<0.05) and the surface density of mitochondrial inner membrane (p<0.05) was lower in the confined doves, while the numerical density of mitochondrial inner membrane was higher (p<0.05). These results suggest that even the short period of restricted exercise can induce negative effects on the functions of myocytes of doves that are adapted for the strong exercise such as flight. Therefore, the maintenance of prolonged exercise seems to be one of the important factors that are critical to retain the functions of myocardium.

• Journal of the Ergonomics Society of Korea
• /
• v.17 no.3
• /
• pp.23-39
• /
• 1998

Several recent aircraft accidents occurred due to goal conflicts between human and machine actors. To facilitate the management of the cockpit activities considering these observations. a computational aid. the Agenda Manager (AM) has been developed for use in simulated cockpit environments. It is important to know pilot intentions performing cockpit operations accurately to improve AM performance. Without accurate knowledge of pilot goals or intentions, the information from AM may lead to the wrong direction to the pilot who is using the information. To provide a reliable flight simulation environment regarding goal conflicts. a pilot goal communication method (GCM) was developed to facilitate accurate recognition of pilot goals. Embedded within AM, the GCM was used to recognize pilot goals and to declare them to the AM. Two approaches to the recognition of pilots goals were considered: (1) The use of an Automatic Speech Recognition (ASR) system to recognize overtly or explicitly declared pilot goals. and (2) inference of covertly or implicitly declared pilot goals via the use of an intent inferencing mechanism. The integrated mode of these two methods could overcome the covert goal mis-understanding by use of overt GCM. And also could it overcome workload concern with overt mode by the use of covert GCM. Through simulated flight environment experimentation with real pilot subjects, the proposed GCM has demonstrated its capability to recognize pilot intentions with a certain degree of accuracy and to handle incorrectly declared goals. and was validated in terms of subjective workload and pilot flight control performance. The GCM communicating pilot goals were implemented within the AM to provide a rich environment for the study of human-machine interactions in the supervisory control of complex dynamic systems.