Numerical Sensitivity Tests of Volatile Organic Compounds Emission to PM2.5 Formation during Heat Wave Period in 2018 in Two Southeast Korean Cities

A record-breaking severe heat wave was recorded in southeast Korea from 11 July to 15 August 2018, and the numerical sensitivity simulations of volatile organic compound (VOC) to secondarily generated particulate matter with diameter of less than 2.5 mu m (PM2.5) concentrations were studied in the Busan and Ulsan metropolitan areas in southeast Korea. A weather research and forecasting (WRF) model coupled with chemistry (WRF-Chem) was employed, and we carried out VOC emission sensitivity simulations to investigate variations in PM2.5 concentrations during the heat wave period that occurred from 11 July to 15 August 2018. In our study, when anthropogenic VOC emissions from the Comprehensive Regional Emissions Inventory for Atmospheric Transport Experiment-2015 (CREATE-2015) inventory were increased by approximately a factor of five in southeast Korea, a better agreement with observations of PM2.5 mass concentrations was simulated, implying an underestimation of anthropogenic VOC emissions over southeast Korea. The simulated secondary organic aerosol (SOA) fraction, in particular, showed greater dominance during high temperature periods such as 19-21 July, 2018, with the SOA fractions of 42.3% (in Busan) and 34.3% (in Ulsan) among a sub-total of seven inorganic and organic components. This is considerably higher than observed annual mean organic carbon (OC) fraction (28.4 +/- 4%) among seven components, indicating the enhancement of secondary organic aerosols induced by photochemical reactions during the heat wave period in both metropolitan areas. The PM2.5 to PM10 ratios were 0.69 and 0.74, on average, during the study period in the two cities. These were also significantly higher than the typical range in those cities, which was 0.5-0.6 in 2018. Our simulations implied that extremely high temperatures with no precipitation are significantly important to the secondary generation of PM2.5 with higher secondary organic aerosol fraction via photochemical reactions in southeastern Korean cities. Other possible relationships between anthropogenic VOC emissions and temperature during the heat wave episode are also discussed in this study

THE HOT GAS DESULFURIZATION IN A COMPACT TWO BEDS SYSTEM INTEGRATED WITH COAL GASIFICATION AND FISHER-TROPSCH SYSTEM

The hot gas desulfurization (HGD) technique is one of the elemental technologies of syngas purification having both thermal efficiency and very low emissions. The HGD is a novel method to efficiently remove H2S and COS in the syngas with regenerable sorbents at high temperature and high pressure condition. We propose a compact hot gas desulfurization system by which its operability is improved in stabilizing pressure balances among units. The proposed compact two beds system has two bubbling beds, solid injection nozzle, solid conveying line, and riser. The compact desulfurization system was located between coal gasifier and Fisher-Tropsch (F-T) reactor to desulfurize syngas in order not to deactivate F-T catalyst. To check feasibility of the compact desulfurization system at high pressure condition, both cold mode and hot mode tests have been performed. In the integrated system, the compact desulfurization system has removed H2S and COS in the syngas and supplied the cleaned syngas to the F-T reactor during the continuous operation at high pressure condition

Nicolau Syndrome after Intramuscular Injection: 3 Cases

Nicolau syndrome is a rare complication of intramuscular injection consisting of ischemic necrosis of skin, soft tissue, and muscular tissue that arises locoregionally. The characteristic pattern is pain around the injection site, developing into erythema, a livedoid dermatitis patch, and necrosis of the skin, subcutaneous fat, and muscle tissue. Three patients were injected with drugs (diclofenac sodium, ketoprofen, meperidine) for pain relief. Three patients complained of pain, and a skin lesion was observed, after which necrosis developed on their buttocks. Each patient underwent debridement and coverage. The wound healed uneventfully. We report three cases of Nicolau syndrome in the buttocks following diclofenac intramuscular injection

A Simple Method for Simulating Horizontal Ozone Concentration Fields over Coastal Areas: A Case Study of the Seoul Metropolitan Area, Korea

This paper describes a simple semi-empirical photo chemical simulation method to generate horizontal ozone (O3) concentration fields over coastal areas. Based on a simple semi-empirical photochemical reaction model (SEGRS), consisting of a simple photochemical reaction set and a diagnostic wind model, aggregated VOC emission strength is empirically scaled from measured photochemical gas phase concentrations of (O3-2NO-NO2) against cumulative actinic light flux for the case of relatively weak off-shore geostrophic wind at 850 hPa in sum mer. This scaled emission rate for volatile organic compounds (VOCs) is equally applied to horizontal O3 concentration simulation under on-shore synoptic conditions, and results are com pared with observations. The results indicate that spatial distribution patterns and temporal variations of spatially aver aged ground level ozone concentrations are reasonably well simulated. In addition, from the more than 100 box-form SEGRS simulations, close agreement between simulated and ob served daily maximum O3 concentrations suggests that the semi empirical SEGRS model has great potential in getting horizontal ozone distribution pat terns. This indicates that this simple semi-empirical approach to the simulation of O3 concentration pat terns using SEGRS makes for an easy alternative method in multi-year simulation for impact studies of O3 concentrations by lowering heavy computational cost

Gastric Syphilis Mimicking Adenocarcinoma: A Case Report

Syphilis is an unexpected diagnosis in the stomach, and the reduced incidence of syphilis has made its clinical presentation less widely appreciated. We report a 43-yr-old man suffering from epigastric tenderness with an initial diagnosis of gastric carcinoma; gastric syphilis was confirmed by demonstrating spirochetes in a gastric biopsy specimen by silver impregnation. Excessive lymphoplasmacytic infiltration with diffuse thickening of gastric rugae should raise suspicion of gastric syphilis, which should be considered in the differential diagnosis of diffuse erosive gastritis and infiltrative lesions of the stomach

An accurate method for quantifying and analyzing copy number variation in porcine KIT by an oligonucleotide ligation assay

<p>Abstract</p> <p>Background</p> <p>Aside from single nucleotide polymorphisms, copy number variations (CNVs) are the most important factors in susceptibility to genetic disorders because they affect expression levels of genes. In previous studies, pyrosequencing, mini-sequencing, real-time PCR, invader assays and other techniques have been used to detect CNVs. However, the higher the copy number in a genome, the more difficult it is to resolve the copies, so a more accurate method for measuring CNVs and assigning genotype is needed.</p> <p>Results</p> <p>PCR followed by a quantitative oligonucleotide ligation assay (qOLA) was developed for quantifying CNVs. The accuracy and precision of the assay were evaluated for porcine <it>KIT</it>, which was selected as a model locus. Overall, the root mean squares of bias and standard deviation of qOLA were 2.09 and 0.45, respectively. These values are less than half of those in the published pyrosequencing assay for analyzing CNV in porcine <it>KIT</it>. Using a combined method of qOLA and another pyrosequencing for quantitative analysis of <it>KIT </it>copies with spliced forms, we confirmed the segregation of <it>KIT </it>alleles in 145 F₁animals with pedigree information and verified the correct assignment of genotypes. In a diagnostic test on 100 randomly sampled commercial pigs, there was perfect agreement between the genotypes obtained by grouping observations on a scatter plot and by clustering using the nearest centroid sorting method implemented in PROC FASTCLUS of the SAS package. In a test on 159 Large White pigs, there were only two discrepancies between genotypes assigned by the two clustering methods (98.7% agreement), confirming that the quantitative ligation assay established here makes genotyping possible through the accurate measurement of high <it>KIT </it>copy numbers (>4 per diploid genome). Moreover, the assay is sensitive enough for use on DNA from hair follicles, indicating that DNA from various sources could be used.</p> <p>Conclusion</p> <p>We have established a high resolution quantification method using an oligonucleotide ligation assay to measure CNVs, and verified the reliability of genotype assignment for random animal samples using the nearest centroid sorting method. This new method will make it more practical to determine <it>KIT </it>CNV and to genotype the complicated <it>Dominant White/KIT </it>locus in pigs. This procedure could have wide applications for studying gene or segment CNVs in other species.</p