• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.2
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• pp.116-121
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• 2017

To overcome the low reactivity and solubility of alkali metal fluorides (MFs), various types of phase transfer catalysts (PTCs) have been developed over the last decades. However, since the fluoride activated by such PTC sometimes has a strong basicity, it may cause various side reactions such as elimination reaction or hydroxylation reaction in the nucleophilic fluorination reaction. Also, they may cause separation problems in the compound purification process. In recent advanced study, various PTCs have been developed to solve these problem of conventional catalyst. In this review, we would like to introduce three kinds of novel multifunctional organic catalysts such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), easy separable pyrene-tagged ionic liquid (PIL) by reduced graphene oxide (rGO), and tri-tert-butanolamine organic catalyst.

• Communications for Statistical Applications and Methods
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• v.18 no.3
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• pp.267-275
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• 2011

According to recent studies, Bayesian information criteria(BIC) is proposed to determine the structural dimension of the central subspace through sliced inverse regression(SIR) with high-dimensional predictors. The BIC may be useful in K-means clustering inverse regression(KIR) with high-dimensional predictors. However, the direct application of the BIC to KIR may be problematic, because the slicing scheme in SIR is not the same as that of KIR. In this paper, we present empirical penalty term studies of BIC in KIR to identify the most appropriate one. Numerical studies and real data analysis are presented.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.433-441
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• 2010

Chenopodium album Linne (CAL) is a fast-growing weedy annual plant. The leaves and young shoots may be eaten as a leafy vegetable. In oriental medicine, CAL has been used for treatment of skin disease, fever, stomach ache, toothache, and paralysis. After a preliminary screening of CAL ethanol extract and its fractions obtained from CAL leaves for anti-gastritic and anti-Helicobacter pylori (H. pylori) activity, the butanol (BuOH) fraction was found to have the most significant effect. We also examined antioxidative properties of the total CAL extract and its fractions, and also betaine as an ingredient of the BuOH fraction. To investigate the antioxidant effects of CAL on gastritis, the reducing power, free radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), and lipid peroxidation effects were determined. Additionally, the BuOH fraction reduced cell viability in a concentration dependent manner in human gastric cancer cell lines. The results of this study revealed that CAL has excellent antioxidant activity, and may be useful in treating gastritis and gastric cancer.

• Journal of Power Electronics
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• v.18 no.4
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• pp.1235-1244
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• 2018

The application of shunt capacitor banks and underground cables typically induces resonance in power distribution systems. In this study, the propagation of resonance in a microgrid (MG) with inverter-based distributed generators (IBDGs) is investigated. If resonances are not properly damped, then the output current of the inverters may experience distortion via resonance propagation due to the adverse effect of resonances on MG power quality. This study presents a conceptual method for identifying resonances and related issues in multi-inverter systems. For this purpose, existing resonances are identified using modal impedance analysis. However, some resonances may be undetectable when this method is used. Thus, the resonances are investigated using the proposed method based on the frequency response of a closed-loop MG equivalent circuit. After analyzing resonance propagation in the MG, an effective virtual impedance damping method is used in the IBDG control system to damp the resonances. Results demonstrate the effectiveness of the proposed method in compensating for existing resonances.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.2
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• pp.378-387
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• 2017

The combined model following control (MFC)-decoupler system is employed for a full authority fly-by-wire utility helicopter to enhance handling qualities. The MFC, which governs the vehicle to follow the prescribed model, is widely employed for modern helicopters. However, it may not be sufficient as helicopters often suffer significant cross coupling. The coupled responses between control axes of a helicopter increase the pilot's work load and may degrade handling qualities. As the decoupler is introduced to the MFC, the combined MFC-decoupler effectively solves the coupling problems and enhances handling qualities. The proposed system is verified via the handling qualities prediction using the mathematical dynamics model. The analysis results are confirmed through the piloted simulation.

• Archives of Craniofacial Surgery
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• v.18 no.1
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• pp.1-4
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• 2017

Frontal sinus outflow tract (FSOT) injury may occur in cases of frontal sinus fractures and nasoethmoid orbital fractures. Since the FSOT is lined with mucosa that is responsible for the path from the frontal sinus to the nasal cavity, an untreated injury may lead to complications such as mucocele formation or chronic frontal sinusitis. Therefore, evaluation of FSOT is of clinical significance, with FSOT being diagnosed mostly by computed tomography or intraoperative dye. Several options are available to surgeons when treating FSOT injury, and they need to be familiar with these options to take the proper treatment measures in order to follow the treatment principle for FSOT, which is a safe sinus, and to reduce complications. This paper aimed to examine the surrounding anatomy, diagnosis, and treatment of FSOT.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.4
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• pp.267-270
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• 2018

As a safety measure, dentures are routinely removed before surgery. Aspiration of a denture could be catastrophic, with medicolegal implications. Foreign body aspiration is uncommon in adults; however, aspirations may remain asymptomatic and undiagnosed for long periods of time. We report an adult male who presented with a cough for more than 6 months. On radiography, a foreign body was found migrating within the tracheobronchial tree from one mainstem bronchus to the other, at different time points. The foreign body was later found to be a portion of his denture. The aspiration may have occurred at the time of a surgical procedure.

• ALGAE
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• v.18 no.4
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• pp.289-294
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• 2003

The age growth pattern of Myagropsis mygroides (Cystoseiraceae, Phaeophyta)population were investigated at Tongyeong (128$^{\circ}$ 25' E and 34$^{\circ}$ 45' N) in South coast of Korea, from September 1998 to August 1999. Water temperatures varied from 7.7${^{\circ}C}$ to 26${^{\circ}C}$ during the survey period. Distinct seasonal changes were found in the plant legth and wet weight of plant, and their maximum length and wet weight were attained 70.5(${\pm}$ 20.9) cm and 191.8(${\pm}$ 135.0) g during April and May. The growth patterns were divided into four periods of slow growth (September-November), fast growth (December-February), maturing growth (March-May) and declining period (June-August). The Tongyeong population of M. myagroides was dominated by less than three-year old small plants with slower growth rates, shorter plant length, lighter plant weight than those of other locations in Korea.

• The Korean Journal of Nuclear Medicine
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• v.39 no.2
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• pp.133-140
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• 2005

The potential for recovery of left ventricular dysfunction after myocardial revascularization represents a practical clinical definition for myocardial viability. The evaluation of viable myocardium in patients with severe global left ventricular dysfunction due to coronary artery disease and with regional dysfunction after acute myocardial infarction is an important issue whether left ventricular dysfunction may be reversible or irreversible after therapy. If the dysfunction is due to stunning or hibernation, functional improvement is observed. but stunned myocardium may recover of dysfunction with no revascularization. Hibernation is chronic process due to chronic reduction in the resting myocardial blood flow. There are two types of myocardial hibernation: "functional hibernation" with preserved contractile reserve and "structural hibernation" without contractile reserve in segments with preserved glucose metabolism. This review focus on the application of F-18 FDG and other radionuclides to evaluate myocardial viability. In addition the factors influencing predictive value of FDG imaging for evaluating viability and the different criteria for viability are also reviewed.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.1
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• pp.65-69
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• 2018

Local anesthesia is administered to control pain, but it may induce fear and anxiety. Root planing is a non-surgical periodontal therapy; however, when it is performed in an extensive manner, some tissue removal is inevitable. Notably, this removal may be so painful that local anesthesia is required to be administered to the area scheduled for the treatment. Although patients tend to accept root planing easily, they frequently express a fear of local anesthesia. Intraosseous anesthesia (IA) is an intraosseous injection technique, whereby local anesthetic is injected into the cancellous bone supporting the teeth. A computer-controlled IA system (CIAS) exhibits multiple benefits, such as less painful anesthesia, reduced soft tissue numbness, and the provision of palatal or lingual, as well as buccal, anesthesia via single needle penetration. In this report, we present two cases of root planing that were performed under local anesthesia, using a CIAS.