Publications by authors named "Jongsung Ahn"

Background: Parameters obtained from two-dimensional (2D) cross-sectional images have been used to determine body composition. However, data from three-dimensional (3D) volumetric body images reflect real body composition more accurately and may be better predictors of patient outcomes in cancer. This study aimed to assess the 3D parameters and determine the best predictive factors for patient prognosis.

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A method was developed for the rapid and quantitative analysis of 30 veterinary drugs belonging to 17 classes (amphenicols (1), anthelmintics (1), cephalosporins (4), coccidiostats (1), lincosamides (1), macrolide (1), nitroimidazole (1), penicillins (3), phenylhydrazines (1), polypeptides (1), pyrethrins (1), quinolones (5), sulfonamides (3), tetracycline (3), neuroleptic agents (1), triazene trypanocidal agents (1), other. (1)) in feeds. The proposed method with a modified Quick Polar Pesticides (QuPPe) sample preparation was validated for the determination of 30 veterinary drugs in feed samples by liquid chromatography triple-quadrupole mass spectrometry (LC-MS/MS).

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Modified QuEChERS and triple quadrupole mass spectrometry (LC and GC-MS/MS) technology were used to sequentially analyze pesticides, veterinary drugs, and mycotoxins in feed. In order to analyze the harmful substances that may remain or occur in the feed, we performed optimization experiments for sample preparation and LC-MS/MS and GC-MS/MS conditions. Optimized sample preparation involves extracting 5 g of sample with 15 mL of 0.

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Background: The bovine pericardium is a good alternative material to the autogenous vein in vascular reconstruction. This study aimed to evaluate the results of angioplasty in venous reconstruction using bovine pericardium and identify the risk factors for significant complications.

Material And Methods: A retrospective review was performed of the demographic data, clinical characteristics, and complications of patients who underwent vessel repair using bovine pericardium between February 2012 and December 2020.

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The analysis of pesticides in food products requires accurate measurements for which standardised protocols have been developed. This paper reports the validation of QuEChERS (quick, easy, cheap, effective, rugged, and safe)-based methods applied to three different food samples (brown rice, red pepper and mandarin orange) analysed using gas chromatography-tandem mass spectrometry (GC-MS/MS). The validation of the analytical methods used to measure 113 pesticides, including various insecticides, fungicides and herbicides, was conducted in three food matrices and at three spiking levels by three different laboratories.

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The determination for the contents of multi-components in ginseng products has come to the fore by demands of in-depth information, but the associated industries confront the high cost of securing pure standards for the continuous quality evaluation of the products. This study aimed to develop a prospective high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) method for relative quantification of ginsenosides in ginseng products without a considerable change from the conventional gradient analysis. We investigated the effects of mobile phase composition and elution bandwidth, which are potential variables affecting the ELSD response in the gradient analysis.

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A large amount-260,000 tons-of red paprika is consumed annually in Korea, where the people prefer hot and pungent to sweet foods. Concern has recently grown among consumers over contamination of paprika powder by mycotoxins; contamination can occur at any stage from pre-harvest to drying, storage, grinding, and eventually transport to the retail market. This study had dual aims: to investigate the current level of contamination of hot peppers by ochratoxin A and to identify the critical control points in the food chain.

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This study was conducted to test the possibility that polyacrylamides used in agriculture may contribute to acrylamide formation in heated foods by thermal depolymerization. Two samples of polyacrylamide with low molecular weights of 1.5 and 10 kDa were used to test for in-chain and end-chain depolymerization.

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