• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.10
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• pp.966-980
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• 2011

Radar receiving echo signal provides target information - range, velocity and position by signal magnitude and Doppler shift, which are determined by target reflection characteristics and target maneuver. Target angle error is extracted from the magnitude ratio of difference channel to sum channel. In this paper, we introduce a radar Return Signal Simulation Equipment(RSSE) which is implemented for the purpose of performance analysis and evaluation of phased array multi-function radar(MFR). It generates multi-target environment with jamming signals using MC-DDS (Multi-Channel Direct Digital Synthesis), and has scalability by using the efficient hardware configuration. The performance of the developed RSSE has been evaluated under various test environments. Especially, we proved that required target detection performance is achieved by RSP(Radar Signal Processor) interfaced RSSE configuration.

• Development and Reproduction
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• v.21 no.3
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• pp.259-267
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• 2017

Present study aimed to determine the effect of 'bitter melon', a popularly used fruit in Bangladesh and several other Asian countries, on high-fat-diet-induced type 2 diabetes. To investigate the effect, ethanol extract from bitter melon (BME) as a dietary supplement with mouse chow was used. BME was found to significantly attenuate the high-fat diet (HFD) -induced body weight and total fat mass. BME also effectively reduced the insulin resistance induced by the HFD. Furthermore, dietary supplementation of BME was highly effective in increasing insulin sensitivity and reducing hepatic fat and obesity. These results indicate that BME could be effective in attenuating type 2 diabetes and could therefore be a preventive measure against type 2 diabetes.

• Journal of Biosystems Engineering
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• v.37 no.1
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• pp.19-27
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• 2012

Purpose: Utilizing air thermal energy during over-heated time in the greenhouse is a necessary component to save greenhouse heating costs for nighttime. However, there is no practical way to implement the related principles. Methods: In this study, a heating and cooling system which utilizes the surplus air thermal energy in a greenhouse was developed. Available air thermal energy and heating load for this experimental glasshouse were estimated based on temperature conditions of the plant growth and weather data. Results: Estimated values were 400 MJ/day for maximum surplus air thermal energy and 340 MJ/day for maximum heating energy which were target values of the design as well. The system consists of a heat pump, fan-coil units and heat storage tanks which are divided into low and high temperature tanks. Moreover, a new control logic was developed for surplus air thermal energy utilization. Conclusions: This paper explains the details of conceptual design process of the system. Results of test operations showed that the developed system performed the recovery and supply of the thermal energy according to design purposes.

• Korean Journal of Pharmacognosy
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• v.38 no.4
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• pp.387-393
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• 2007

By screening inhibitory activities on the melanin polymer biosynthesis in B-16 mouse melanoma cell lines, MeOH extract of Phellodendri Cortex was found to have inhibitory effect on melanin polymer biosynthesis. Twelve compounds were isolated from the MeOH extract of P. Cortex. They were identified as obacunone (1), limonin (2), ${\beta}-sitosterol$ (3), bis(2-methylheptyl) phthalate (4), cycloeucalenol (5), berberine (6), palmatine (7), jatrorrhizine (8), syringin (9), umbelliferone (10), rutaecarpine (11) and scopoletin (12) by comparison of their physical and spectral data with those of authentic samples. Among the isolated compounds, berberine (6) and palmatine (7) showed potent inhibitory effect on the melanin polymer biosynthesis in cultured B-16 mouse melanoma cell lines, with Inhibition rate of 96% and 90%, respectively. As a positive control, arbutin exhibited an inhibition rate of 56%.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2226-2230
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• 2007

As a cathode material of lithium rechargeable batteries, charged Li[Co0.1Ni0.15Li0.2Mn0.55]O2 electrodes, which were aged thermally at 25 oC and 90 oC respectively, were characterized by means of charge/discharger, impedance spectroscopy, and X-ray diffraction. The discharge capacity diminution of the electrodes aged at 25 oC and 90 oC for 1 week was 4% and 23%, respectively. The cell aged at 25 oC was recovered on cycling. However, the capacity loss after ageing at 90 oC was not recovered in a subsequent cycling test, which demonstrates that the reaction occurring during ageing at 90 oC is irreversible. A significant impedance increase of aged electrode at 90 oC is associated with irreversible capacity loss. The structural changes including phase transformation were not detected by XRD analysis, because it could be due to out of detection limit. After ageing, impedance was slightly decreased during subsequent cycling test. It could be explained the cyclic performance of aged sample is stable. The thermal stability was not deteriorated by ageing even at the high temperature of 90 oC.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.244-247
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• 2006

Neuronal cell death significantly contributes to neuronal loss in neurological injury and disease. Typically, neuronal loss or destruction upon exposure to neurotoxins, oxidative stress, or DNA damage causes neurodegenerative diseases such as Alzheimer's disease. In this study, we attempted to determine whether ginsenoside Rg3 from red ginseng has a neuroprotective effect via an anti-apoptotic role induced by S-nitroso-N-acetylpenicillamine (SNAP) at the molecular level. We also investigated the antioxidant effect of Rg3 using a metal-catalyzed reaction with $Cu^{2+}/H_2O_2$. Our results showed that Rg3 ($40-100\;{\mu}g/mL$) protected SK-N-MC neuroblastoma cells under cytotoxic conditions and effectively protected DNA from fragmentation. In the signal pathway, caspase-3, and poly (ADP-ribose) polymerase (PARP) were kept at an inactivated status when pretreated with Rg3 in all ranges. In particular, the important upstream p-Akt signal pathway was increased in a dose-dependent manner, which indicates that Rg3 may contribute to cell survival. We also found that oxidative stress can be mitigated by Rg3. Therefore, we have concluded that Rg3 plays a certain role in neurodegenerative pathogenesis via an anti apoptotic, antioxidative effect.

• Journal of Yeungnam Medical Science
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• v.29 no.1
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• pp.28-30
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• 2012

A 48-year-old male visited the emergency room of the authors' hospital due to nausea, vomiting, and myalgia for four days. Acute hepatitis A was identified from the serologic marker of the hepatitis A virus. Mild elevation of the serum creatinine and creatinine phosphokinase (CPK) suggested rhabomyolysis, which was confirmed with the serum aldolase, myoglobin, and urine myoglobin. With supportive care, both the liver and renal functions were recovered gradually and fully. This case shows that rhabdomyolysis can be one of the mechanisms of renal complication in cases of acute symptomatic hepatitis A.

• Journal of Chest Surgery
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• v.53 no.2
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• pp.53-57
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• 2020

Background: Video-assisted thoracoscopic surgery (VATS) lobectomy has become the major surgical option for the treatment of non-small cell lung cancer (NSCLC). Endoscopic instruments such as stapler cartridges are essential for VATS procedures. In this study, we investigated the factors that affect the number of stapler cartridges used in VATS lobectomy. Methods: A retrospective analysis was conducted of patients who underwent complete VATS lobectomy for NSCLC from January 2013 to December 2015. Results: In total, 596 patients underwent complete VATS lobectomy. The average number of stapler cartridges used for VATS lobectomy was 5.3±1.9. The number of stapler cartridges used for VATS lobectomy was higher in men (5.5±1.9 vs. 5.0±18, p=0.006), those aged older than 70 years (5.5±2.1 vs. 5.1±1.7, p=0.038), those who underwent upper or middle lobectomy procedures (5.7±1.9 vs. 4.1±1.2, p<0.001), those with a higher fissure sum average (p<0.001), and those in whom surgery was performed by a surgeon with a preference for staplers (5.6±2.0 vs. 4.9±1.6, p<0.001). Conclusion: The number of stapler cartridges required to perform VATS lobectomy in NSCLC patients appears to be influenced by sex, age, the location of the tumor, the degree of fissure development, and the surgeon's preference.

• Mycobiology
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• v.45 no.3
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• pp.129-138
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• 2017

In this study, we aimed to characterize fungal samples from necrotic lesions on collar regions observed in different sweetpotato growing regions during 2015 and 2016 in Korea. Sclerotia appeared on the root zone soil surface, and white dense mycelia were observed. At the later stages of infection, mother roots quickly rotted, and large areas of the plants were destroyed. The disease occurrence was monitored at 45 and 84 farms, and 11.8% and 6.8% of the land areas were found to be infected in 2015 and 2016, respectively. Fungi were isolated from disease samples, and 36 strains were preserved. Based on the cultural and morphological characteristics of colonies, the isolates resembled the reference strain of Sclerotium rolfsii. Representative strains were identified as S. rolfsii (teleomorph: Athelia rolfsii) based on phylogenetic analysis of the internal transcribed spacer and large subunit genes along with morphological observations. To test the pathogenicity, sweetpotato storage roots were inoculated with different S. rolfsii strains. 'Yulmi' variety displayed the highest disease incidence, whereas 'Pungwonmi' resulted in the least. These findings suggested that morphological characteristics and molecular phylogenetic analysis were useful for identification of S. rolfsii.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.245-251
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• 2009

Objective : The authors analyzed the effectiveness and therapeutic response of Novalis shaped beam radiosurgery for metastatic brain tumors, and the prognostic factors which influenced the outcome. Methods : We performed a retrospective analysis of 106 patients who underwent 159 treatments for 640 metastatic brain lesions between January 2000 and April 2008. The pathologies of the primary tumor were mainly lung (45.3%), breast (18.2%) and GI tract (13.2%). We classified the patients using Radiation Therapy Oncology Group Recursive Partitioning Analysis (RPA) and then analyzed the survival and prognostic factors according to the Kaplan Meier method and univariate analysis. Results : The overall median actuarial survival rate was 7.3 months from the time of first radiosurgery treatment while 1 and 2 year actuarial survival estimates were 31% and 14.4%, respectively. Median actuarial survival rates for RPA classes I, II, and III were 31.3 months, 7.5 months and 1.7 months, respectively. Patients' life spans, higher Karnofsky performance scores and age correlated closely with RPA classes. However, sex and the number of lesions were not found to be significantly associated with length of survival. Conclusion : This result suggests that Novalis radiosurgery can be a good treatment option for treatment of the patients with brain metastases.