• Food Science and Preservation
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• v.23 no.1
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• pp.131-138
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• 2016

This study was conducted to investigate the change in the quality of early season Fuji apples that were subjected to eight different storage conditions using the developed controlled atmosphere (CA) storage system. Early season Fuji apples grown at Mungyeong, in the South Korea, were harvested in September 2014 for storage studies. Flesh firmness, titratable acidity, total soluble solid content, weight loss, and internal browning disorder were used as quality indicators for the stored apples. Flesh firmness and weight loss were better than that of the control after 70 days of storage. However, there was no significant difference in the titratable acidity or total soluble solid content among the apple samples from eight chambers after storage. The internal browning disorder of apple samples in CA chambers occurred when exposed to 1% $CO_2+2%$ $O_2$ and 1% $CO_2+0.5%$ $O_2$, resulting in a higher incidence rate of 2 and 8% after 70 days of storage than that in the control. In addition, the CA storage conditions at 3, 4 and 5% $CO_2+2%$ $O_2$ increased the rate of internal browning disorder by 26%. Therefore, CA storage can be used to maintain the quality of the apple if the optimal gas concentrations in the CA are applied to the storage strategy.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.312-315
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• 2014

The present study demonstrated the development and validation of the method for the quantification of phenol in food using gas chromatography coupled with mass spectrometry (GC-MS). After spiking of internal standard (Phenol-$d_5$) to food, those samples were extracted with organic solvent mixture (acetone : dichloromethane = 1 : 1, v/v) using ultra sonic extractor and cleaned by gel permeation chromatography (GPC) technique. The amount of phenol was determined by GC/MS. To validate the developed method, we evaluated parameters were the selectivity, linearity, accuracy, precision, and recovery. To demonstrate the selectivity of the method, blank samples of rice, corn, and fish(mackerel) were prepared and subjected to GC-MS analysis. To verify the linearity of the method, six different standard concentrations of phenol at 0.01, 0.05, 0.1, 0.5, 1 and 2.5 mg/kg were evaluated. The correlation coefficient ($r^2$) of calibration curve was 0.9999. The recovery rate for phenol standard calculated by internal standard method were 82.2~101.5% for samples fortified with 0.25, 0.50, and 1.0 mg/kg, respectively. Also the repeatability and reproducibility for validation of precision were 0.2~5.5%. According to the result of the validation, this established method was suitable for AOAC guideline. The limit of detection (LOD) for phenol analysis were 0.03~0.1 mg/kg, and the limit of quantification (LOQ) were 0.1~0.3 mg/kg. Therefore, we established the optimal analysis method for determination of phenol in food using GPC and GC/MS.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.331-341
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• 2022

This study was conducted to identify yeast species isolated from domestic pear blossom through gene sequencing and analysis of morphological characteristics, and to confirm specific yeast species inhibitory effects toward fire blight in immature apples, pears, and crab apple blossoms. Yeast morphological characteristics were consistent with the known characteristics of Aureobasidium pullulans. Nucleotide sequencing of the D1/D2 region of large-subunit (LSU) 26S ribosomal DNA and the internal transcribed spacer (ITS) region confirmed its identity as A. pullulans (MHAU2101). Inoculation of immature fruits with A. pullulans MHAU2101 before exposure to Erwinia amylovora prevented fire blight symptoms in apples and pears. A. pullulans MHAU2101 treated crab apple blossoms had a significantly lower flower infection rate than untreated blossoms, revealing 64% of the potency of streptomycin. The A. pullulans MHAU2101 treated group also displayed lower E. amylovora density in both pistil and hypanthium compared to the untreated group, especially in the hypanthium. This study confirms that A. pullulans MHAU2101 isolated from domestic pear blossom can effectively suppress the onset of fire blight.

• International Journal of Oral Biology
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• v.49 no.1
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• pp.18-25
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• 2024

Despite advancements in therapeutic approaches, radiotherapy and cisplatin-based chemotherapy remain primary noninvasive treatments for patients with oral squamous cell carcinoma (OSCC). Moreover, the 5-year survival rate for patients with OSCC has remained almost unchanged for several decades, and many side effects of chemotherapy still exist. In this study, three-dimensional (3D) models of OSCC were established using fibroblasts, and the efficacy of various biological inhibitors was evaluated. A culture of epithelial cells with two types of fibroblasts (hTERT-hNOFs and cancer-associated fibroblasts) within a type I collagen matrix resulted in the formation of a continuous layer of tightly packed cells compared to models without fibroblasts. Furthermore, the effects of biological chemicals, including Y27632, latrunculin A, and verteporfin, on these models were investigated. The stratified formation of the epithelial layer and invasion in OSCC 3D-culture models were effectively inhibited by verteporfin, whereas invasion was weakly inhibited by Y27632 and latrunculin. Collectively, the developed OSCC 3D-culture models established with fibroblasts demonstrated the potential for drug screening, with verteporfin showing promising efficacy.

• Mycobiology
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• v.42 no.2
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• pp.114-119
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• 2014

The wood decay fungi Antrodia P. Karst. play important ecological roles and have significant industrial and economic impacts as both wood degraders and sources of pharmaceutical and biotechnological products. Although each Antrodia species has distinct morphological characteristics, the misidentification rate is especially high due to their simple morphological characters. A combination of morphological and internal transcribed spacer region sequence analyses revealed that 27 of 89 specimens previously identified by morphology alone were correct, whereas 35 of these specimens were misidentified as other Antrodia species. We report here that seven Antrodia species exist in Korea (A. albida, A. heteromorpha, A. malicola, A. serialis, A. sinuosa, A. sitchensis, and A. xantha) and based on these specimens, we provide taxonomic descriptions of these species, except for A. serialis, which was only confirmed by isolate.

• Childhood Kidney Diseases
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• v.23 no.2
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• pp.116-120
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• 2019

Bilateral renal obstruction is a rare critical condition, requiring a prompt diagnostic approach and treatment to restore the renal function. The most commonly observed obstructive uropathy in children is congenital malformation, such as posterior urethral valves and bilateral ureteropelvic junction obstruction. Malignant pelvic masses obstructing the ureter are widely reported in adults but are rarely observed in children. The treatment of ureteral obstruction related to pelvic malignancy is a therapeutic challenge with a median survival duration of 3-7 months in adults; however, pediatric patients with pelvic malignancy leading to ureteral obstruction had better outcomes, with a reported 5-year mortality rate of 20%, than the adult patients. Here, we report a rare case of bilateral ureteral obstruction associated with pelvic rhabdomyosarcoma presenting with acute kidney injury treated by ureteral diversion with double J stent, and concommittent emergency hemodialysis, leading to restoration of good renal function. We suggest that bilateral ureteral obstruction should be released as soon as possible using surgical or interventional approach to minimize the obstruction period, and subsequential chemotherapy may contribute to improvement of survival and recovery of renal function.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.10
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• pp.739-744
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• 2012

This paper describes the blower performance used for single-stage high pressure regenerative blower. The blower considered is widely applied to the field of a fuel cell system, a medical equipment and a sewage treatment plant. Flow rate and rotating frequency of a impeller of the blower are considered as design parameters for the proper operation of the blower. Three-dimensional Navier-Stokes equations are introduced to analyze the performance and internal flow of the blower. Relatively good agreement between experimental measurements and numerical simulation is obtained. Throughout a numerical simulation, it is found that small and stable vortical flow generated inside the blade passage is effective to increase pressure and efficiency of the blower. Large local recirculation flow having low velocity in the blade passage obstructs the generation of stable vortical flow, thus increases the pressure loss of the blower. Detailed flow field inside the blower is also analyzed and discussed.

• Elastomers and Composites
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• v.36 no.3
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• pp.153-161
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• 2001

The rubber pads era tank which undergo dynamic deformations with the sufficient amplitudes and frequencies lead to a considerable internal temperature rise due to the heat generation. The heat generation which is dependent on the viscoelastic characteristics or a rubber is due to the conversion of partial mechanical energy into thermal energy identical to the area oi hysteresis loop. Heat generation without adequate heat dissipation leads to heat build-up and the excessive temperature rite exerts a bad influence upon the performance and the life of rubber products. In this paper, temperature distributions of the rubber pads of a tank track subjected to dynamic loads are obtained under the assumption of the steady state. Heat generation rates used in this finite element analysis are acquired through experiments and the computed temperature fields are displayed in isothermal contour regions.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.2
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• pp.91-99
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• 2014

The common-rail injectors are the most critical component of the CRDI diesel engines that dominantly affect engine performances through high pressure injection with exact control. Thus, from now on the advanced combustion technologies for common-rail diesel injection engine require high performance fuel injectors. Accordingly, the previous studies on the numerical and experimental analysis of the diesel injector have focused on a optimum geometry to induce proper injection rate. In this study, computational predictions of performance of the diesel injector have been performed to evaluate internal flow characteristics for various needle lift and the spray pattern at the nozzle exit. To our knowledge, three-dimensional computational fluid dynamics (CFD) model of the internal flow passage of an entire injector duct including injection and return routes has never been studied. In this study, major design parameters concerning internal routes in the injector are optimized by using a CFD analysis and Response Surface Method (RSM). The computational prediction of the internal flow characteristics of the common-rail diesel injector was carried out by using STAR-CCM+7.06 code. In this work, computations were carried out under the assumption that the internal flow passage is a steady-state condition at the maximum needle lift. The design parameters are optimized by using the L16 orthogonal array and polynomial regression, local-approximation characteristics of RSM. Meanwhile, the optimum values are confirmed to be valid in 95% confidence and 5% significance level through analysis of variance (ANOVA). In addition, optimal design and prototype design were confirmed by calculating the injection quantities, resulting in the improvement of the injection performance by more than 54%.

• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.13-20
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• 2008

Internal and external reproductive parameters of the striped bitterling, Acheilognathus yamatsutae were compared. Internal reproductive parameters was used gonadosomatic index (GSI), hepatosomatic index (HSI) and gonadal development stage. External reproductive parameters was used ovipositor in female and pearl organ, dorsal and caudal fin nuptial color in male. The GSI and HSI of the female and male showed highest in February. Gonadal development was observed mainly ripe and spawning/spent stage in February to May. The ovipositor length index (OLI) of the female showed highest in March to April. Pearl organ number and expression rate of the male showed highest in February to May. Dorsal fin nuptial color expression rate and index (NCI-DF) showed highest in February to May. Caudal fin nuptial color expression rate and index(NCI-CF) showed highest in February to April. The study suggested same change of internal and external reproductive parameters in female and male.