• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.66-74
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• 2020

Marine algae contain a variety of substances, such as mycosporine-like amino acids, which can defend against UV irradiation. Among them, Porphyra-334 derived from Porphyra yezoensis is attracting attention as a novel active ingredient for anti-aging cosmetics because of its excellent anti-oxidative, anti-inflammatory, and wound-healing properties through promoting skin cell migration. In this study, a process using direct current (DC) for increasing the yield of large-scale purification of Porphyra-334 was developed. When DC was applied to obtain Porphyra-334 efficiently, the purification time was shortened by approximately 1/4 compared with the process wherein DC was not applied; moreover, the yield of purification was improved.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.12C
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• pp.1677-1685
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• 2004

Recently, FD (Frame Dropping)-CD (Coefficient Dropping) transcoding is considered due to the low computational complexity and simple implementation. The conventional FD-CD transcoding schemes have not considered the CD errors that tend to be propagated and accumulated. In this paper, we derive the error characteristics incurred by the CD errors and, through computer simulations, we show that the CD errors are propagated and not negligible to the decoded qualities of the next frames within single GOP. Then, we propose an exponential-decaying model that describes well the characteristics of propagation/accumulation errors. Finally, it is shown that the proposed model can be effectively used for estimating the overall distortions incurred by the CD errors.

• Journal of Power Electronics
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• v.19 no.2
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• pp.509-518
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• 2019

A novel islanding detection method is proposed in this paper. It is based on a frequency drooping PLL, which was presented in a previous work. The cause of errors in the non-detection zone (NDZ) of conventional frequency disturbance islanding detection methods (IDM) is analyzed. A frequency drooping phase-locked-loop (FD-PLL) is introduced into a single-phase grid-connected inverter (SPGCI), which can guarantee that grid current is in phase with the grid voltage. A novel FD-PLL IDM is proposed by improving this PLL. In order to verify the performance of the proposed FD-PLL IDM, a full performance comparison between the proposed IDM and typical existing active frequency drift IDMs is carried out, which includes both dynamic performance and steady performance. With the same NDZ, the total harmonic distortion of the grid-current in the dynamic process and steady state is analyzed. The proposed FD-PLL IDM, regardless of the dynamic or steady process, has the best power quality. Experimental and simulation results verify that the proposed FD-PLL IDM has excellent performance.

• Journal of the Korean Society of Food Culture
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• v.39 no.3
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• pp.156-165
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• 2024

Sprout products, such as broccoli, alfalfa, and cabbage, have positive health effects. Thus far, sprout foods have attracted attention owing to their good bioavailability. In particular, young broccoli sprouts exhibit anti-inflammatory, antioxidant, and anti-cancer effects. They contain 100 times more chemoprotective substances than adult broccoli. This study examined the anti-inflammatory effects of freeze-dried young sprout broccoli (FD-YB) in vitro using RAW264.7 macrophage cells. The FD-YB powder antioxidant ability test showed that the radical-scavenging activity and superoxide dismutase enzyme activity increased in a dose-dependent manner. In addition, FD-YB was not cytotoxic to RAW264.7 cells, and nitric oxide production decreased after the FD-YB treatment of lipopolysaccharide-stimulated RAW264.7 cells in a dose-dependent manner. Furthermore, FD-YB significantly decreased the expression of inflammation-related proteins (Cyclooxygenase-2, Inducible nitric oxide synthase, and Prostaglandin E Synthase 2) and cytokines (Tumor necrosis factor-α and Interleukin-6). In conclusion, FD-YB can be a potential nutraceutical for preventing and regulating excessive immune responses during inflammation.

• The Journal of Korean Medicine
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• v.28 no.2 s.70
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• pp.80-92
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• 2007

Objectives : Functional dyspepsia (FD) is one of the most common gastrointestinal diseases. Nevertheless, there are many unknown mechanisms of autonomic functioning in FD patients. This study was designed to investigate the relationship between FD and biosignals from heart rate variability (HRV) and Yangdorak diagnosis. Methods : 32 patients (22 female, 10 male; mean age 40) and 32 healthy volunteers (21 female, 11 malemean; age 38) participated in this study. First gastrointestinal symptoms rating scale (GSRS) was assessed by questionnaires in both groups to evaluate the types of gastrointestinal symptoms. Second, HRV and Yangdorak diagnosis were measured in both groups. Results : 1. The FD group in this study mainly had the complaint of 'bloating' symptoms. 2. There was statistically no significant difference between Yangdorak (total average and 24 acupoints) and HRV values except logarithmic low-frequency band (lnLF) and total power (TP) in frequency domain. 3. There was statistically no significant relationship between HRV and Yangdorak in either group. However, most Yangdorak values were positively related with some HRV values (low-frequency, low-frequency/high-frequency ratio and high-frequency, etc) in the control group. Conclusions : FD patients had relatively lesser sympathetic domain than healthy subjects, indicated by decreased lnLF and TP. Particularly, there were positive relationships and significant differences between Yangdorak and HRV in young healthy subjects. This suggests that biosignals from HRV may be a useful method that can differentiate FD from healthy state in those of young age.

• The Journal of Internal Korean Medicine
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• v.42 no.6
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• pp.1173-1183
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• 2021

Objectives: This study investigated the clinical characteristics of functional dyspepsia (FD) patients with food retention (FR) in regard to the parameters of cutaneous electrogastrography (EGG), Ryodoraku, and heart rate variability (HRV). Methods: This study reviewed the clinical records of 33 FD patients with FR who filled out the FR Questionnaire for FD (FRQ-FD) and underwent EGG for six months from March 1st, 2021. We summarized the clinical characteristics of FD patients with FR and analyzed the correlation between FRQ-FD score and parameters of EGG, Ryodoraku, and HRV. Results: FRQ-FD scores had a positive correlation with percentage of postprandial bradygastria and negative correlation with power ratio, detected on Channel 2, 3 of EGG. The total average (TA) Ryodoraku score was lower, and the high frequency density (HF) of HRV was higher than the normal value. Conclusions: The results of this study suggest that clinicians can use EGG, Ryodoraku, and HRV to increase the accuracy of diagnosing FR in FD patients.

• Journal of Korean Dental Science
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• v.16 no.2
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• pp.211-217
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• 2023

Fibrous dysplasia (FD) accompanying osteomyelitis (OM) has been reported to result in recurrent, refractory pain and swelling. Although radical resection of the lesions has been suggested, effective surgical treatment strategies have not yet been established due to the limited number of studies on this pathological condition. In this report, we present the conservative surgical management of FD accompanying OM in two patients who exhibited recurrent signs and symptoms. The present report suggests that OM occurring in patients with FD can be successfully managed with conservative surgical treatment and following removal of the odontogenic origin although bone defect in which inflammatory fibro-osseous lesions is removed through decompression surgery may exhibit regeneration of dysplastic bone. In addition, for the prevention of OM in patients with FD, careful clinical examination and thorough management of dental-related pathologies are necessary with regular follow-up examinations to screen for the possibility of malignant changes.

• The Journal of Internal Korean Medicine
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• v.41 no.4
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• pp.563-582
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• 2020

Objectives: The aim of this study was to develop a Phlegm Pattern Questionnaire for Functional Dyspepsia (PPQ-FD) by modifying a previously developed Phlegm Pattern Questionnaire (PPQ) and to verify its reliability and validity. Further objectives were to obtain the optimal cut-off value for the PPQ-FD for standardization and for clinical use. Methods: The PPQ-FD was developed by extracting the major symptoms of the phlegm pattern in functional dyspepsia and by using the Delphi method to administer a requested importance survey to experts. The reliability, validity, and optimal cut-off value of the PPQ-FD were analyzed by enrolling a total of 60 subjects in this study. Thirty patients were diagnosed with both functional dyspepsia and phlegm pattern and thirty patients were diagnosed with only functional dyspepsia. All participants were requested to fill out the PPQ-FD. Results: No statistically significant differences were detected in the two groups for sex distribution, age, or body mass index. Five of the survey questions negatively affected its reliability; therefore, we decided to exclude those five questions on further inspection. The Cronbach's α coefficient of the revised PPQ-FD was 0.853, and clinical validity was verified. Construct validity was analyzed by factor analysis and identified four factors. Statistically significant positive correlations were found between the revised PPQ-FD and other dyspepsia scales, such as the SQDQ, SSQD, VAS, NDI-K, and FD-QoL scales. The VAS had particularly strong positive correlations with the PPQ-FD. Conclusions: The PPQ-FD developed in this study has fundamental reliability and validity for use as a pattern-diagnosis questionnaire. The PPQ-FD can help to diagnose the phlegm pattern in patients with functional dyspepsia.

• Archives of Craniofacial Surgery
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• v.24 no.5
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• pp.244-249
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• 2023

Fibrous dysplasia (FD) is a rare skeletal disorder characterized by abnormal fibro-osseous connective tissue replacing normal bone. Despite its benign behavior, craniofacial FD can cause morphological disfigurement, headache, and even blindness as a result of the produced mass effect. Surgical resection is recommended when the patient shows apparent clinical symptoms or aggravating facial asymmetry. Postoperative complications have been reported, such as hematoma, surgical site infection, abscess formation, resorption of the bone graft used for reconstruction, and recurrence. An aneurysmal bone cyst (ABC) is a rare benign bony lesion that can occur secondary to preexisting bone tumor. Secondary ABCs in craniofacial FD are extremely rare in the literature, accounting for less than 30, all of which are either case reports or series. We report an extremely rare case of symptomatic secondary ABC arising from craniofacial FD that had been misdiagnosed with abscess formation or recurrence and was surgically removed. Notably, 17 years elapsed between the primary surgery and the complication of secondary ABC. The patient underwent total removal of secondary ABC. After surgery, symptoms were relieved, with no recurrence observed during a 6-month follow-up.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1532-1537
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• 2024

Time-of-flight (TOF) PET detectors with fast-rise-time scintillators and fast-single photon time resolution silicon photomultiplier (SiPM) have been developed to improve the coincidence timing resolution (CTR) to sub-100 ps. The CTR can be further improved with an optimal bandwidth and minimized electronic noise in the readout circuit and this helps reduce the distortion of the fast signals generated from the TOF-PET detector. The purpose of this study was to develop an ultra-high frequency and fully-differential (UF-FD) readout circuit that minimizes distortion in the fast signals produced using TOF-PET detectors, and suppresses the impact of the electronic noise generated from the detector and front-end readout circuits. The proposed UF-FD readout circuit is composed of two differential amplifiers (time) and a current feedback operational amplifier (energy). The ultra-high frequency differential (7 GHz) amplifiers can reduce the common ground noise in the fully-differential mode and minimize the distortion in the fast signal. The CTR and energy resolution were measured to evaluate the performance of the UF-FD readout circuit. These results were compared with those obtained from a high-frequency and single ended readout circuit. The experiment results indicated that the UF-FD readout circuit proposed in this study could substantially improve the best achievable CTR of TOF-PET detectors.