• Journal of Korean Society for Atmospheric Environment
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• v.25 no.3
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• pp.219-236
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• 2009

Particle-phase organic tracers (molecular markers) have been shown to be an effective method to assess and quantify the impact of sources of carbonaceous aerosols. These molecular markers have been used in chemical mass balance (CMB) models to apportion primary sources of organic aerosols in regions where the major organic aerosol source categories have been identified. As in the case of all CMB models, all important sources of the tracer compounds must be included in a Molecular Marker CMB (MM-CMB) model or the MMCMB model can be subject to biases. To this end, the application of the MM-CMB models to locations where reasonably accurate emissions inventory of organic aerosols are not available, should be performed with extreme caution. Of great concern is the potential presence of industrial point sources that emit carbonaceous aerosols and have not been well characterized or inventoried. The current study demonstrates that emissions from industrial point sources in the St. Louis, Missouri area can greatly bias molecular marker CMB models if their emissions are not correctly addressed. At a sampling site in the greater St. Louis Area, carbonaceous aerosols from industrial point sources were found to be important source of carbonaceous aerosols during specific time periods in addition to common urban sources (i.e. mobile sources, wood burning, and road dust). Since source profiles for these industrial sources have not been properly characterized, method to identify time periods when point sources are impacting a sampling site, needs to avoid obtaining biases source apportionment results. The use of real time air pollution measurements, along with molecular marker measurements, as a screening tool to identify when point sources are impacting a receptor site is presented.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.167-172
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• 2011

A three-dimensional ecological model (EMT-3D) was applied to Tokyo Bay to simulate 4,4'-bis (2-sulfostyryl)biphenyl (DSBP). The simulated results were in good agreement with the observed values, with a correlation coefficient of R=0.8431 and a coefficient of determination of $R^2$=0.7108. The sensitivity analysis indicated that the photolysis rate is the most important factor. Therefore, the parameters must be considered carefully in modeling. The mass balance results showed that the standing stock of DSBP in water and in particulate organic carbon was 621.2 and 19.5 kg, respectively, and the effluent flux to the open sea was 2.63 and 0.055 kg/day, respectively.

• Journal of Korean Society on Water Environment
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• v.37 no.5
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• pp.355-362
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• 2021

This study investigated the fate of dissolved organic matter (DOM) in a water reclamation facility (WRF) in Korea. The WRF consists of coagulation, sedimentation, microfiltration, and reverse osmosis (RO) components. The production capacity of WRF is 90,000 m³/day. The reclaimed water is reused as industrial water. We also characterized DOM in raw, processed, and finished waters based on analysis of dissolved organic carbon (DOC), ultraviolet absorbance at 254 nm (UVA₂₅₄), fluorescence excitation emission matrix (FEEM), and DOC fractions via liquid chromatography-organic carbon detection (LC-OCD). Based on the results of DOC, UVA₂₅₄, and FEEM analyses, neither the coagulation/sedimentation nor the microfiltration at the WRF effectively removed DOM. The RO process removed more than 94% of DOM. The raw water (i.e., secondary treated effluent obtained from a wastewater treatment plant) exhibited tryptophan-like peaks, which are a promising marker of wastewater, in the FEEM analysis. Coagulation and microfiltration failed to eliminate the wastewater marker, whereas RO completely removed it. The raw water also carried high levels (89.4%) of hydrophilic and low-molecular weight substances, which are difficult to remove via coagulation-sedimentation or microfiltration. Humic substance was a major component of the hydrophilic fractions. Based on the LC-OCD analysis, RO effectively removed the humic and polymeric materials from DOM.

• Asian Journal of Atmospheric Environment
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• v.11 no.3
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• pp.165-175
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• 2017

In Japan, the primary carbonaceous particles emitted from motor vehicles and waste incinerators have been reduced due to strict regulations against exhaust gas. However, the relative contribution of carbonaceous particles derived from plants and biomass has been increasing. Accordingly, compositional analysis of carbonaceous particles has become increasingly important to determine the sources and types of particles produced. To reveal the sources of the organic particles contained in particulate matter with diameters of ${\leq}2.5{\mu}m$ ($PM_{2.5}$) and the processes involved in their generation, we analyzed molecular marker compounds (2-methyltetrols, cis-pinonic acid, and levoglucosan) derived from the plants and biomass in the $PM_{2.5}$ collected during daytime- and nighttime-sampling periods in summer (July and August) and autumn (November) in Kazo, which is in the northern area of Saitama prefecture, Japan. We also measured $^{14}C$ carbonaceous concentrations in the same $PM_{2.5}$ samples. The concentrations of 2-methyltetrols were higher in the summer than in the autumn. Because the deciduous period overlaps with this decrease in the levels of 2-methyltetrols, we considered the emission source to broad-leaved trees. In contrast, the emission source of the cis-pinonic acid precursor was considered to be conifers, because its concentration remained almost constant throughout the year. The concentration of levoglucosan was considerably increased in the autumn due to frequent biomass open burning. The ratio of plant-derived carbon to total carbon, obtained by measuring of $^{14}C$, in summer $PM_{2.5}$ sample was higher in the nighttime, and could be influenced by anthropogenic sources during the daytime.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.745-757
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• 2018

We analyzed the nuclear ribosomal internal transcribed spacer (ITS) sequence of common buckwheat, Fagopyrum esculentum and tartary buckwheat, F. tataricum. The diversity of the nucleotides and haplotypes, Tajima's D, and Fu's Fs was analyzed and compared among the varieties of common buckwheat and tartary buckwheat. The diversity of nucleotides and haplotypes indicated that the buckwheat populations had undergone rapid population expansion but D and Fs did not support their expansion statistically. The phylogenetic analysis of ITS sequences did not clearly establish the phylogenetic relationships between the varieties of common buckwheat. The In/Del sequence of ITS-1 region could, therefore, be used as a DNA marker to distinguish raw or manufactured products derived from common buckwheat and tartary buckwheat.

• ALGAE
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• v.36 no.2
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• pp.123-135
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• 2021

The taxonomy of green microalgae relies traditionally on morphological traits but has been rapidly changing since the advent of molecular methods. Stichococcus Nägeli is a cosmopolitan terrestrial algal genus of the class Trebouxiophyceae that has recently been split into seven lineages, which, along with Pseudostichococcus, comprise the Stichococcuslike group; there is a need to further characterize these genera, since they are morphologically enigmatic. Here we used organic osmolytes as chemotaxonomic marker to verify the phylogenetic position of Stichococcus-like strains and were also able to exclude a strain hitherto identified as Gloeotila contorta from this group. Stichococcus-like organisms, including those recently revised, were characterized by the production of the polyol sorbitol and the disaccharide sucrose in high amounts, as is typical of Prasiola-clade algae. The results demonstrate that organic osmolyte chemotaxonomy can support green algal taxonomic designations as fundamental research.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.5
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• pp.482-492
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• 2015

Ground-based measurements were conducted from January 6 to 12 of 2015 for understanding characteristics of nitrogen containing carbonaceous aerosols as 16 amino acids at the Mokpo National University, Korea. The detailed amino acid components such as Cystine ($(SCH_2CH(NH_2)CO_2H)_2$) and Methionine ($C_5H_{11}NO_2S$) and their sources were analyzed by High-Performance Liquid Chromatography with Fluorescence Detection (HPLC-FLD) for behavior of secondary products in particulate matter. In addition, organic carbon (OC) and elemental carbon (EC) based on the carbonaceous thermal distribution (CTD), which provides detailed carbon signature characteristics relative to analytical temperature, and water soluble organic carbon (WSOC) by total organic carbon (TOC) analyzer were used to understand the carbon compound behaviors. The backward trajectories were discussed for originations of carbonaceous aerosols as well. Different airmasses were classified with the amino acids and OC thermal signatures. The results can provide to understand the aging process influenced by the long-range transport from East Sea area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.167-176
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• 2011

Brown planthopper (BPH) is a serious insect pest of rice crop throughout rice growing countries, and yield loss due to its infection can be up to 60%. This study aimed to evaluate efficiency of molecular markers for screening BPH resistance accessions among 86 aromatic rice germplasm Eighty-six accessions of aromatic rice germplasm included two accessions of Tongil type (bred in Korea), 28 accessions of japonica type and 56 accessions of indica type. We applied eight STS markers (pBPH9, pBPH19, pBPH20, pBPH21, AJ09-b, RG457L, RG457B, and 7312.T4A) which were linked to four of BPH resistance genes, Bph1, Bph13(t), Bph10, and Bph18(t) respectively. One japonica type accession, 415XIr352, and six indica type accessions possessed one or four positive bands when tested with four STS markers linked to Bph1 gene. One indica type aromatic rice, Basmati9-93, showed the target bands linked to the Bph10 gene. The other accessions did not show same fragments as the respective resistant lines. Bph13(t) is the most widely introduced resistance gene and only one accession showed positive bands implying that this accession might harbor Bph10 and Bph18(t) genes. Three aromatic accessions, Domsiah, Khao Dawk Mali 105 and 415XIr352 showed gene pyramiding of Bph1 and Bph13(t). Two indica aromatic rice, Ds 20 and Basmati 9-93, possessed at least two BPH resistance genes, Bph1, Bph18(t) and Bph13(t), Bph18(t), respectively. These results indicates that aromatic rice germplasm have narrow diversities of BPR resistance genes.

• Journal of mucopolysaccharidosis and rare diseases
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• v.2 no.1
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• pp.13-16
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• 2016

Mucolipidosis (ML) II/III are autosomal recessive diseases caused by deficiency of post-translational modification of lysosomal enzymes. The mannose-6-phosphate (M6P) residue in lysosomal enzymes synthesized by N-acetylglucosamine 1-phosphotransferase (GlcNAc-phosphotransferase) serves as recognition marker for trafficking in lysosomes. GlcNAc-phosphotransferase is encoded by GNPTAB and GNPTG. Mutations in GNPTAB cause severe ML II alpha/beta and the attenuated ML III alpha/beta. Whereas mutations in GNPTG cause the ML III gamma, the attenuated type of ML III variant. For the diagnostic approaches, increased urinary oligosaccharides excretion could be a screening test in clinically suspicious patients. To confirm the diagnosis, instead of measuring the activity of GlcNAc phosphotransferase, measuring the enzymatic activities of different lysosomal hydrolases are useful for diagnosis. The activities of several lysosomal hydrolases are decreased in fibroblasts but increased in serum of the patients. In addition, the sequence analysis of causative gene is warranted. Therefore, the confirmatory diagnosis requires a combination of clinical evaluation, biochemical and molecular genetic testing. ML II/III show complex disease manifestations with lysosomal storage as the prime cellular defect that initiates consequential organic dysfunctions. As there are no specific therapy for ML to date, understanding the molecular pathogenesis can contribute to develop new therapeutic approaches ultimately.

• Asian Journal of Atmospheric Environment
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• v.6 no.1
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• pp.53-66
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• 2012

A comparison of analytical approaches for Levoglucosan ($C_6H_{10}O_5$, commonly formed from the pyrolysis of carbohydrates such as cellulose) and used for a molecular marker in biomass burning is made between the four different analytical systems. 1) Spectrothermography technique as the evaluation of thermograms of carbon using Elemental Carbon & Organic Carbon Analyzer, 2) mass spectrometry technique using Gas Chromatography/mass spectrometer (GC/MS), 3) Aerosol Mass Spectrometer (AMS) for the identification of the particle size distribution and chemical composition, and 4) two dimensional Gas Chromatography with Time of Flight mass spectrometry (GC${\times}$GC-TOFMS) for defining the signature of Levoglucosan in terms of chemical analytical process. First, a Spectrothermography, which is defined as the graphical representation of the carbon, can be measured as a function of temperature during the thermal separation process and spectrothermographic analysis. GC/MS can detect mass fragment ions of Levoglucosan characterized by its base peak at m/z 60, 73 in mass fragment-grams by methylation and m/z 217, 204 by trimethylsilylderivatives (TMS-derivatives). AMS can be used to analyze the base peak at m/z 60.021, 73.029 in mass fragment-grams with a multiple-peak Gaussian curve fit algorithm. In the analysis of TMS derivatives by GC${\times}$GC-TOFMS, it can detect m/z 73 as the base ion for the identification of Levoglucosan. It can also observe m/z 217 and 204 with existence of m/z 333. Although the ratios of m/z 217 and m/z 204 to the base ion (m/z 73) in the mass spectrum of GC${\times}$GC-TOFMS lower than those of GC/MS, Levoglucosan can be separated and characterized from D (-) +Ribose in the mixture of sugar compounds. At last, the environmental significance of Levoglucosan will be discussed with respect to the health effect to offer important opportunities for clinical and potential epidemiological research for reducing incidence of cardiovascular and respiratory diseases.