This study developed innovative predictive models of groundwater pollution using in situ electrical conductivity (EC) and oxidation-reduction potential (ORP) measurements at livestock carcass burial sites. Combined electrode analysis (EC and ORP) and machine learning techniques efficiently and accurately distinguished between leachate and background groundwater. Two models-empirical and theoretical-were constructed based on a supervised classification framework.
View Article and Find Full Text PDFThis study introduces a novel groundwater pollution index (GPI) formulated through compositional data analysis (CoDa) and robust principal component analysis (RPCA) to enhance groundwater quality assessment. Using groundwater quality monitoring data from sites impacted by the 2010-2011 foot-and-mouth disease outbreak in South Korea, CoDa uncovers critical hydrochemical differences between leachate-influenced and background groundwater. The GPI was developed by selecting key subcompositional parts (NH-N, Cl, and NO-N) using RPCA, performing the isometric log-ratio (ILR) transformation, and normalizing the results to environmental standards, thereby providing a more precise and accurate assessment of pollution.
View Article and Find Full Text PDFThe occurrence of various N-related human activities increases the difficulty in distinguishing the major sources of NO contamination in groundwater, especially in areas with mixed land uses. In addition, the estimation of the timing and pathways of NO is necessary to better understand the processes of NO contamination in the subsurface aquifer system. This study applied environmental tracers, such as stable isotopes and age tracers (δN and δO of NO, δB, chlorofluorocarbons, and H), to elucidate the sources, timing, and pathways of NO contamination in the groundwaters of the Hanrim area, which has suffered from illegal disposal of livestock wastes since the 1980s, and also characterizes them based on mixed N-contaminant sources such as chemical fertilizers and sewage.
View Article and Find Full Text PDFNano plastics (NPs) have been a significant threat to human health and are known to cause premature endothelial senescence. Endothelial senescence is considered one of the primary risk factors contributing to numerous cardiovascular disorders. Recent studies have suggested that inhibition of sodium glucose co-transporter (SGLT2) ameliorates endothelial senescence and dysfunction.
View Article and Find Full Text PDFPurpose: The genetic attribution for pancreatic ductal adenocarcinoma (PDAC) has been reported as 5%-10%. However, the incidence of germline pathogenic variants (PVs) in Korean PDAC patients has not been thoroughly investigated. Therefore, we studied to identify the risk factors and prevalence of PV for future treatment strategies in PDAC.
View Article and Find Full Text PDFIn the fault classification process, filter methods that sequentially remove unnecessary features have long been studied. However, the existing filter methods do not have guidelines on which, and how many, features are needed. This study developed a multi-filter clustering fusion (MFCF) technique, to effectively and efficiently select features.
View Article and Find Full Text PDFTransdifferentiation (or activation) of hepatic stellate cells (HSCs) to myofibroblasts is a key event in liver fibrosis. Activated HSCs in the tumor microenvironment reportedly promote tumor progression. This study analyzed the effect of an inhibitor of HSC activation, retinol-binding protein-albumin domain III fusion protein (R-III), on protumorigenic functions of HSCs.
View Article and Find Full Text PDFAdenylate kinase 5 (AK5) belongs to the adenylate kinase family that catalyses reversible phosphate transfer between adenine nucleotides, and it is related to various energetic signalling mechanisms. However, the role of AK5 in colorectal cancer (CRC) has not been reported. In this study, AK5 was significantly hypermethylated in CRC compared to adjacent normal tissues (P < 0.
View Article and Find Full Text PDFActivation of quiescent hepatic stellate cells (HSCs) to myofibroblasts plays a key role in liver fibrosis. We had previously shown that albumin and its derivative, R-III (a retinol-binding protein-albumin domain III fusion protein), inhibited HSC activation by sequestering retinoic acid (RA) and that R-III administration reduced carbon tetrachloride (CCl)-induced liver fibrosis. In this study, we aimed to elucidate the mechanism of action of albumin downstream of RA sequestration.
View Article and Find Full Text PDFTotal synthesis of cyclopiamide A was accomplished using a palladium-catalyzed domino cyclization. Three rings in the tetracyclic skeleton of cyclopiamide A were constructed in a one-step domino reaction incorporating double carbopalladation and C-H activation.
View Article and Find Full Text PDFDuring in situ bioremediation, continuous injection of growth substrates such as carbon sources, electron donors, or electron acceptors inevitably results in microbial growth, resulting in biological clogging in an aquifer. Therefore, for successful bioremediation, development of a new injection method is needed to reduce or alleviate this clogging problem. In this study, we carried out field tracer tests using single-well push-pull tests (SWPPTs), single-well natural gradient drift tests (SWNGDTs), and long-term in situ well-to-well tests to develop and evaluate a new method of liquid/gas mixture spray injection.
View Article and Find Full Text PDFThis study assessed the feasibility of an in situ well-based denitrification bio-barrier (WDB) for managing groundwater contaminated with high-strength nitrate. To evaluate the efficacy of WDB using fumarate as a carbon source and/or electron donor, three sequential single-well push-pull tests (SWPPTs) were conducted at six test sites. The values of the isotope enrichment factor (ɛ) ranging from -6.
View Article and Find Full Text PDFBackground: Interstitial fibrosis and tubular atrophy (IFTA) is a well-recognized risk factor for poor renal outcome in patients with diabetic kidney disease (DKD). However, a noninvasive biomarker for IFTA is currently lacking. The purpose of this study was to identify urinary markers of IFTA and to determine their clinical relevance as predictors of renal prognosis.
View Article and Find Full Text PDFGenerally different anaerobic degradation potentials for benzene, toluene, ethylbenzene and xylene isomers (BTEX) has been reported due to site specific conditions, such as the indigenous microbial population, electron acceptors (EA) available and concentrations of each BTEX compound. It was of interest to estimate relative biodegradation potential of each BTEX compound during enhanced anaerobic bioremediation of a BTEX-contaminated aquifer. In this study, an in situ method for assessing the degradation potentials of each BTEX compound present as a mixture under NOinjecting conditions by performing a series of single-well push-pull tests and well-to-well tests (WWTs) was developed.
View Article and Find Full Text PDFA foot-and-mouth disease (FMD) outbreak during 2010 affected the entire country of South Korea and approximately 3.4 million swine and bovine mortalities were disposed of at approximately 4800 on-farm burial sites for a few months following the first outbreak. Furthermore, outbreaks of avian influenza (AI) have struck Korea consistently since 2014.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2019
Ferrihydrite, or iron(III) (oxyhydr)oxide (Fe(OH)), a representative scavenger of environmentally relevant toxic elements, has been repurposed as a low-cost and scalable precursor of well-developed hematite (α-FeO) secondary nanoclusters with a hierarchically structured morphology for lithium-ion anode materials. Here, we report that the bacteria Clostridium sp. C8, isolated from a methane-gas-producing consortium, can synthesize self-assembled secondary hematite nanoclusters (∼150 nm) composed of small nanoparticles (∼15 nm) through the molecular structural rearrangement of amorphous ferrihydrite under mild conditions.
View Article and Find Full Text PDFJ Environ Sci Health A Tox Hazard Subst Environ Eng
May 2019
This study demonstrates a combined field method accurately assessing the extent of trichloroethylene (TCE) reductive dechlorination activity and the mass fraction of its by-products. A combined method of injecting a known concentration of 1,1,2-trichloro-2-fluoroethene (TCFE) as a TCE bio-surrogate and a data processing technique of forced mass balance (FMB), considering the sorption effect on the mass fraction of chloroethene was evaluated by performing soil column and field bioaugmentation tests. In the soil column test, the FMB resulted in the mass fraction of 6% TCE, 48.
View Article and Find Full Text PDFWe demonstrate adsorption and partial incorporation of arsenic, in its soluble form, either as arsenite or arsenate into lepidocrocite (γ-FeOOH), which was formed through nitrite-driven Fe(II) oxidation by Paracoccus denitrificans under nitrate-reducing conditions. Fe and As K-edge XANES and radial distribution functions of Fourier-transformed EXAFS spectra showed that portions of As were found to be incorporated in the biogenic lepidocrocite, in addition to higher portions of adsorbed As. We suggest that denitrifying bacteria such as Paracoccus denitrificans, studied here, could facilitate decrease of aqueous arsenic As(III) and/or As(V) through indirect Fe(II) oxidation to solid phase iron minerals, here as lepidocrocite, by the denitrification product nitrite in the presence of nitrate, ferrous iron, and arsenic, under certain environmental conditions where these materials could be found, such as in As-contaminated paddy soils and wetlands.
View Article and Find Full Text PDFBased on consecutive one-pot conditions combining three palladium-catalyzed reactions (Sonogashira, Heck and Suzuki-Miyaura reactions), a more efficient domino multicomponent method has been successfully developed to access a wide variety of 3-(diarylmethylene)oxindoles. Microwave irradiation and use of a silver salt were the most important factors to achieve high yields and stereoselectivity.
View Article and Find Full Text PDFBackground: DNA hypermethylation is a key epigenetic mechanism for the silencing of many genes in cancer. Hinokitiol, a tropolone-related natural compound, is known to induce apoptosis and cell cycle arrest and has anti-inflammatory and anti-tumor activities. However, the relationship between hinokitiol and DNA methylation is not clear.
View Article and Find Full Text PDFAspirination of α-aminoalcohol (sarpogrelate M1) has been performed under various general esterification conditions. In most cases, the desired aspirinate ester was obtained at a low yield with unexpected byproducts, the formation of which was mostly derived from the chemical properties of the tertiary α-amino group. After systematic analysis of those methods, the aspirinated sarpogrelate M1 was prepared using a two-step approach combining salicylate ester formation and acetylation.
View Article and Find Full Text PDFTrophoblast invasion ability is an important factor in early implantation and placental development. Recently, pituitary tumor transforming gene 1 (PTTG1) was shown to be involved in invasion and proliferation of cancer. However, the role of PTTG1 in trophoblast invasion remains unknown.
View Article and Find Full Text PDFObjective: Cilostazol is a Biopharmaceutical Classification System class II drug with low solubility and high permeability, so its oral absorption is variable and incomplete. The aim of this study was to prepare two sulfonate salts of cilostazol to increase the dissolution and hence the oral bioavailability of cilostazol.
Methods: Cilostazol mesylate and cilostazol besylate were synthesized from cilostazol by acid addition reaction with methane sulfonic acid and benzene sulfonic acid, respectively.
3-(Diarylmethylene)oxindoles have been synthesized from propiolamidoaryl triflate utilizing a palladium-catalyzed one-pot reaction consisting of three successive reactions: Sonogashira, Heck, and Suzuki-Miyaura. This method allows for the production of a complex skeleton of 3-(diarylmethylene)oxindole from propiolamidoaryl triflate using a commercially available aryl iodide and arylboronic acid in a simple and efficient way with moderate yield and stereoselectivity.
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