• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.95.1-95.1
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• 2013

The RBSPICE (Radiation Belt Storm Probes Ion Composition Experiment) is one of five instrument suites onboard the twin Van Allan Probes (or Radiation Belt Storm Probes; RBSP), launched August 30, 2012 by NASA. One of science targets of RBSPICE instrument is to determine "how changes in that ring current affect the creation, acceleration, and loss of radiation belt particles?". For that purpose, it measures ions and electrons simultaneously. Ion's energy range is from ~20 keV to ~1 MeV and electron's energy channel is from ~35 keV to 1 MeV in order to provide supplementary information about the radiation belts. In this paper, we investigate a reliability of the electron flux measured from the RBSPICE by comparing with ECT (The Energetic Particle, Composition and Thermal Plasma Suite) data. We found there is a critical proton contamination problem in the electron channels of ~ 1MeV of RBSPICE observations during one moderate storm event of Sym H ~ -76 nT on March 1, 2013.

• Bulletin of the Korean Space Science Society
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• 2010.04a
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• pp.40.2-40.2
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• 2010

It has been reported that geosynchronous magnetopause crossings are more frequently observed in the prenoon sector than in the postnoon sector, indicating a dawn-dusk magnetopause asymmetry during extreme solar wind conditions. Motivated by these observations, we investigate geosynchronous magnetic field variations normalized to SYM-H when sudden commencements (SC) are observed on the ground. From a statistical analysis of the geosynchronous magnetic field responses to SC events from 1997 to 2006, we found that the normalized SC amplitude at geosynchronous orbit is larger in the morning sector than in the afternoon sector. In order to examine if this morning-afternoon asymmetry at geosynchronous orbit occurs only during disturbed geomagnetic conditions, we compared the geosynchronous magnetic field strength obtained in the morning and afternoon during undisturbed intervals (Kp < 3). We found that the asymmetry appears under undisturbed geomagnetic conditions and it is not due to solar wind aberration. This indicates that the morning-afternoon asymmetry was not strongly affected by changes in solar wind condition. Using solar wind data, we discuss what causes the morning-afternoon asymmetry at geosynchronous orbit.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.14-20
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• 1991

- The purpose of this work is to investigate the effects of various substrates on biosynthesis of ethylene by the Kudzu strain of Pseudomonas syn'ngae pv. Phaseolicola causing halo blight. In the intact cell of P. sym'ngue, optimal condition for ethylene production was achieved at p1-I 7.5 and $30^{\circ}C$ for 9 to 10 hours of culture. Ethylene was most effectively produced from amino acids such as Asn, Gln, Asp ans Glu, compared to those of various kinds of sugars. While ethylene production from $\alpha$-ketoglutarate ($\alpha$-KG) was gradually increased throughout 51 hours incubation period tested. Ethylene production derived from citrate, $\alpha$-KG and oxalacetate as well as a few amino acids was further enhanced by the addition of histidine or arginine. In cell-free ethylene-forming system, ethylene was most effectively produced from $\alpha$-KG, compared to those from citrate, oxalacetate, Glu, Arg, or Asp, at 0.5 mM among the range from 0.25 mM to 5 mM. Anlinooxyacetate, an inhibitor of a pyridoxal phosphate-linked enzyme, completely inhibited ethylene evolution derived from Glu but not affect that derived from $\alpha$-KG. The results obtained in this work suggest that $\alpha$-KG might be a direct precursor of ethylene production in this organism than any other substrates tested.

• Journal of Astronomy and Space Sciences
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• v.26 no.4
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• pp.451-466
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• 2009

While substorms are known to generally occur under southward IMF conditions, they can sometimes occur even under northward IMF conditions. In this paper, we studied the substorms that occurred in May, 2000 to 2002 to examine some statistical characteristics of the IMF and solar wind associated with northward IMF substorms. We focused on the cases where two or more substorms occurred successively under northward IMF conditions. Also, by checking Sym-H index associated with each of the substorms we determined whether or not there is any association of such northward IMF substorm occurrence with storm times. We also examined statistical properties at geosynchronous altitude in terms of magnetic field dipolarization and energetic particle injection. The following results were obtained. (i) Most of the northward IMF substorms occurred under average solar wind conditions. The majority of them occurred within 2 hrs duration of northward IMF Bz state, but there are also a nonnegligible number of substorms that occurred after a longer duraiton of northward IMF Bz state. (ii) While most of the substorms occurred as isolated from a magnetic storm time, those that occurred in a magnetic storm time show a higher average value of IMF and solar wind than that for the isolated substorms. (iii) About 55% of the substorms were associated with the IMF clock angle that can possibly allow dayside reconnection, and the other 45% were associated with more or less pure northward IMF conditions. Therefore, for the latter cases, the energy input from the solar wind into the magnetosphere should be made by other way than the dayside reconnection. (iv) For most of the substorms, the magnetic field dipolarizations and energetic particle injections at geosynchronous altitude were identified to be generally weak. But, several events indicated strong magnetic field dipolarizations and energetic particle injections.

• Journal of Astronomy and Space Sciences
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• v.34 no.4
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• pp.237-244
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• 2017

Magnetic flux ropes, often observed during intervals of interplanetary coronal mass ejections, have long been recognized to be critical in space weather. In this work, we focus on magnetic flux rope structure but on a much smaller scale, and not necessarily related to interplanetary coronal mass ejections. Using near-Earth solar wind advanced composition explorer (ACE) observations from 1998 to 2016, we identified a total of 309 small-scale magnetic flux ropes (SMFRs). We compared the characteristics of identified SMFR events with those of normal magnetic cloud (MC) events available from the existing literature. First, most of the MCs and SMFRs have similar values of accompanying solar wind speed and proton densities. However, the average magnetic field intensity of SMFRs is weaker (~7.4 nT) than that of MCs (~10.6 nT). Also, the average duration time and expansion speed of SMFRs are ~2.5 hr and 2.6 km/s, respectively, both of which are smaller by a factor of ~10 than those of MCs. In addition, we examined the geoeffectiveness of SMFR events by checking their correlation with magnetic storms and substorms. Based on the criteria Sym-H < -50 nT (for identification of storm occurrence) and AL < -200 nT (for identification of substorm occurrence), we found that for 88 SMFR events (corresponding to 28.5 % of the total SMFR events), substorms occurred after the impact of SMFRs, implying a possible triggering of substorms by SMFRs. In contrast, we found only two SMFRs that triggered storms. We emphasize that, based on a much larger database than used in previous studies, all these previously known features are now firmly confirmed by the current work. Accordingly, the results emphasize the significance of SMFRs from the viewpoint of possible triggering of substorms.

• Journal of muscle and joint health
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• v.5 no.1
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• pp.39-56
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• 1998

This study was an quasi-experimental study, done to identify factors Influencing the reduction of symptoms in patients with fibromyalgia. The primary purpose of the study was to develop a Self-Help Program suitable for patients with fibromyalgia in Korea. The secondary purpose was to identify the effects of a Self-Help Program which included stretching exercise. This study was carried out between Feb. 24 and July 8, 1997 and patients in the study Included out patient diagnosed with fibromyalgia based on the criteria developed by the American College of Rheumatology(1990) and H, University which is a tertiary patient care clinic for Rheumatism. The experimental group included 38 patients who were residents of Seoul or Kyungi province, and a control group of 38 patients who were residents of other areas. The control patients were matched to the experimental group patients and they were selected considering the number of tender points on the Fibromyalgia Impact Questionnaire score and a score of self-efficacy. The experimental group participated in a Self-Help Program based on the American Arthritis Foundation(1995) guidelines. The program participants participated in a small group which consisted of 12-15 members attending the program once a week, for 6 weeks with each program lasted two to two and a half hours. The stretching exercise was carried out in each patient's home every day following the video tape exercise provided by the researcher, and the researcher provided encouragement and concern to the patients by calling them once a week. The number times the exercise was performed was divided by the number of participants to calculate the percentage of performance and determine the amount of exercise. Self-efficacy was measured by the Self-Efficacy Scale developed by Lorig et al. (1989) for arthritis patients. The degree of pain was converted to scores based on the Visual Analog Scale, the number of tender points was converted to scores based on the criteria of the ACR(1990) and of Yunus. Depression was measured by CES-D and physical disability, sleep disturbance, fatigue, and anxiety of patients with fibromyalgia were measured by the Fibromyalgia Impact Questionnaire. The level of the exercise performance was converted to scores using the number of times the exercise was performed following the video tape prepared by Association of Rheumatology Health Professionals. Data were analyzed by SPSS windows and the results ire described below. 1. The experimental group which participated in the Self-Help Program showed higher efficacy scores than the control group when both groups were analyzed for depression and the number of tender points as common variables(F=9.146, p=.003). 2. The experimental group which participated in the Self-Help Program showed lower scores than the control group, for pain, the number of tender points, depression, physical disability, fatigue, sleep disturbance and anxiety. These symptoms of fibromyalgia can all be seen to have subsided(F=9.483, p=.003 : F=32.680, p=.001 ; F=11.104, p=.001, F=5.344 : p=.024, F=7.630 : P=.007, F=15.6512, p=.003 : F= 7.5412, p=.008). 3. In the experimental group, the self-efficacy score for the first three weeks showed a positive correlation with the exercise-performance score for four to six weeks (r=.387, p=.043). 4. In the experimental group, the relationship between the level of exercise-performance and the reduction of symptoms showed a significant correlation only to physical disability(r= -.500, p=.001). 5. In the experimental group, the relationship between the self-efficacy score and pain, the number of tender points, depression, physical disability, fatigue, sleep disturbance and anxiety score showed inverse correlations and thus, a reduction of symptoms occured when the self-efficacy score increased(r=-.325, p=.004 ; r= -.253, p=.027, r=-.452, p=.001 : r=-.434, p=.001 ; r=-.316, p=.005 ; r=-.460, p=.001 ; r=-.397, p=.014). Therefore, self-efficacy improved following the Self-Help Program including the stretching exercise. It was also found that physical symptoms (pain, number of tender points, level physical disability) and psychological symptoms (depression, fatigue, sleep disturbance, anxiety) were reduced. Moreover, It was found that the higher the self-efficacy, the the higher the degree of achievement of goals set for the stretching exercises. In addition, the level of exercise-performance influenced the level of physical disability, one of the symptoms of fibromyalgia. Accordingly, the conclusions from this study are that exercise-performance and the reduction of symptoms is achieved through promotion of self-efficacy. Therefore, it is proposed that are the Self-Help Program including stretching exercises is an appropriate nursing intervention for the reduction of symptoms of fibromyalgia.