Search

Analyzing the formation mechanisms of industrial parks and quantitatively evaluating the related hazard levels are important for understanding the development and planning of industrial parks, but there is currently a lack of relevant research. In this study, Beijing was taken as a case study. The analysis results showed that (1) the overall spatial distribution of industrial parks in Beijing followed a clustering pattern, with nested spatial distribution pattern, where larger structures contributed 53.96% of the variance; (2) for the overall spatial distribution of industrial parks, kernel density of enterprises was the main influencing factor, which there were synergistic enhancement effects with almost all other influencing factors, especially urban construction, the number of financial institutions, the population density, this can share transportation and other resources, achieving coordinated development. According to these main factors, the prediction model of the future spatial distribution pattern of industrial parks in Beijing was established; (3) for site selection of each industrial park, twenty-two industrial parks near industrial enterprises in Beijing were more affected by industrial enterprise clustering, and the remaining 65 industrial parks were strongly affected by terrain, (4) The industrial parks in the central and southern parts of Beijing presented a relatively high hazard level to the surrounding sensitive receptors. These results provide theoretical support for the development and layout of industrial parks. [ABSTRACT FROM AUTHOR]

This study considers the identification of the Nonlinear Auto-Regressive with eXogenous Inputs (NARX) models of the rotor systems, in which the identified NARX model may sometimes fail. By incorporating rotor response signals at different speeds into the modeling process using an Extended Forward Orthogonal Regression (EFOR) algorithm. This way, the data information involved in identification is more abundant, but this is still not enough. To completely solve the issue, an identification method based on Model Prediction Output (MPO) error is proposed in this paper. Which can filter all possible identification results during the identification process based on MPO error, thereby avoiding potential failed identification results and obtaining the optimal solution. The proposed method improves the accuracy of NARX model identification and reduces the need for professional knowledge. The simulation and experimental cases of a rub-impact rotor system are presented to illustrate the application and the effectiveness of the new identification approach. [ABSTRACT FROM AUTHOR]

Over the past decade, a substantial body of research exploring soundscapes in religious historical buildings has emerged, yet a comprehensive summary of this work is lacking. This paper selects 74 typical studies of soundscapes in religious historical buildings published between 2011 and 2022 to conduct quantitative statistics and visualization analysis from a bibliometric perspective. The selected literature is categorized based on the type of religious building, Christian, Islamic, or Buddhist. The literature is further segmented according to the research subject, including sound field studies, sound analyses, and evaluations of the acoustic environment. The research methods employed are also differentiated and include sound field measurements, acoustic simulations, questionnaires and auralization procedures. The analysis reveals pronounced disparities in research foci depending on the type of religious historical building. For instance, studies on the soundscape in Christian churches tend to focus on objective sound field attributes and frequently employ sound field simulations to analyse the acoustic parameters of diverse church spaces and materials. Conversely, research on the soundscape in Islamic mosques prioritizes speech intelligibility and acoustic comfort, while studies of the soundscape of Buddhist temples gravitate towards the impact of natural and religious sounds on individuals. This paper anticipates the future direction of soundscape research on religious historical buildings. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the role and therapeutic value of homocysteine (hcy)-inducible endoplasmic reticulum stress (ERS) protein with ubiquitin like domain 1 (Herpud1) in hcy-induced calcific aortic valve disease (CAVD). Background: The morbidity and mortality rates of calcific aortic valve disease (CAVD) remain high while treatment options are limited. Methods: In vivo, we use the low-density lipoprotein receptor (LDLR) and Herpud1 double knockout (LDLR−/−/Herpud1−/−) mice and used high methionine diet (HMD) to assess of aortic valve calcification lesions, ERS activation, autophagy, and osteogenic differentiation of aortic valve interstitial cells (AVICs). In vitro, the role of Herpud1 in the Hcy-related osteogenic differentiation of AVICs was investigated by manipulating of Herpud1 expression. Results: Herpud1 was highly expressed in calcified human and mouse aortic valves as well as primary aortic valve interstitial cells (AVICs). Hcy increased Herpud1 expression through the ERS pathway and promoted CAVD progression. Herpud1 deficiency inhibited hcy-induced CAVD in vitro and in vivo. Herpud1 silencing activated cell autophagy, which subsequently inhibited hcy-induced osteogenic differentiation of AVICs. ERS inhibitor 4-phenyl butyric acid (4-PBA) significantly attenuated aortic valve calcification in HMD-fed low-density lipoprotein receptor−/− (LDLR−/−) mice by suppressing ERS and subsequent Herpud1 biosynthesis. Conclusions: These findings identify a previously unknown mechanism of Herpud1 upregulation in Hcy-related CAVD, suggesting that Herpud1 silencing or inhibition is a viable therapeutic strategy for arresting CAVD progression. Highlights: • Herpud1 is upregulated in the leaflets of Hcy-treated mice and patients with CAVD. • In mice, global knockout of Herpud1 alleviates aortic valve calcification and Herpud1 silencing activates cell autophagy, inhibiting osteogenic differentiation of AVICs induced by Hcy. • 4-PBA suppressed Herpud1 expression to alleviate AVIC calcification in Hcy treated AVICs and to mitigate aortic valve calcification in mice. [ABSTRACT FROM AUTHOR]

W-substituted rare-earth niobates (LnNb1 − xWxO4 + δ (Ln = Nd, Sm, Eu, Gd)) have been systematically synthesized by a solid-state reaction method. Powder X-ray diffraction at room temperature revealed that the monoclinic fergusonite phase structure of unsubstituted samples gradually changes to a tetragonal scheelite phase structure with increasing W substitution. The crystal structures of the samples with x ≥ 0.3 can be refined well (goodness-of-fit indicator S ≤ 1.5) as the tetragonal scheelite structure. The W substitution improves the ionic conductivities of the four rare-earth niobates, and all of their optimum W substitution amount (x) are 0.2. The activation energy of the conductivity for the substituted samples is almost constant regardless of the type of rare-earth ion, the temperature, and the W substitution amount. [ABSTRACT FROM AUTHOR]

Brain subcortical structures are paramount in many cognitive functions and their aberrations during infancy are predisposed to various neurodevelopmental and neuropsychiatric disorders, making it highly essential to characterize the early subcortical normative growth patterns. This study investigates the volumetric development and surface area expansion of six subcortical structures and their associations with Mullen scales of early learning by leveraging 513 high-resolution longitudinal MRI scans within the first two postnatal years. Results show that (1) each subcortical structure (except for the amygdala with an approximately linear increase) undergoes rapid nonlinear volumetric growth after birth, which slows down at a structure-specific age with bilaterally similar developmental patterns; (2) Subcortical local area expansion reveals structure-specific and spatiotemporally heterogeneous patterns; (3) Positive associations between thalamus and both receptive and expressive languages and between caudate and putamen and fine motor are revealed. This study advances our understanding of the dynamic early subcortical developmental patterns. Studies of early brain development often rely on cross sectional data. Here the authors investigate volumetric development and surface area expansion of six subcortical structures using longitudinal MRI scans within the first two postnatal years. [ABSTRACT FROM AUTHOR]

Beijing's industrial structure is changing rapidly, and many small and dispersed businesses are becoming major contributors of VOC emissions. There are about 740 auto parts enterprises in Beijing, and is typical of a small industry in which VOC emissions cannot be ignored. Two typical water-based paint auto parts electrophoresis enterprises in Beijing were selected in this study. The results show that the annual average VOC emissions of both enterprises were 3.72 t, while the unorganized emissions accounted for 36.2%. The analysis of VOC emissions characteristics in the exhausts revealed that oxygenated VOCs (OVOCs) (acetone, 2-butanone, ethyl acetate, etc.) were the most abundant components (~ 21.88–68.66%), followed by alkanes (~ 6.93–25.34%), and olefins (~ 2.67–50.44%). The concentrations of VOCs (ρ(VOCs)) from drying chimney were 8.941 mg/m3, while the electrophoresis process accounted for 0.792 mg/m3. The comparison of the effects of VOCs treatment facilities demonstrated that regenerative thermal oxidizer and thermal oxidizer increased the VOC concentration instead of decreased, due to a large amount of gas supplemented. The activated carbon adsorption was ineffective in treating non-polar VOCs such as alkanes, while the neutralizing absorption was relatively stable. In addition, the ozone formation potential and health risk assessments (cancer and non-cancer risks) show that water-based enterprises are still partially at risk. Based on the emission characteristics of VOCs and the technical feasibility, it is recommended to improve the collection rate of disorganized exhaust gas from electrophoresis workshop, adjust the values of emission standards, and optimize the end treatment measures of the drying workshop. [ABSTRACT FROM AUTHOR]

Clinical and biomarker phenotypic associations for carriers of protein function-altering variants may help to elucidate gene function and health effects in populations. We genotyped 1127 Strong Heart Family Study participants for protein function-altering single nucleotide variants (SNV) and indels selected from a low coverage whole exome sequencing of American Indians. We tested the association of each SNV/indel with 35 cardiometabolic traits. Among 1206 variants (average minor allele count = 20, range of 1 to 1064), ~ 43% were not present in publicly available repositories. We identified seven SNV-trait significant associations including a missense SNV at ABCA10 (rs779392624, p = 8 × 10–9) associated with fasting triglycerides, which gene product is involved in macrophage lipid homeostasis. Among non-diabetic individuals, missense SNVs at four genes were associated with fasting insulin adjusted for BMI (PHIL, chr6:79,650,711, p = 2.1 × 10–6; TRPM3, rs760461668, p = 5 × 10–8; SPTY2D1, rs756851199, p = 1.6 × 10–8; and TSPO, rs566547284, p = 2.4 × 10–6). PHIL encoded protein is involved in pancreatic β-cell proliferation and survival, and TRPM3 protein mediates calcium signaling in pancreatic β-cells in response to glucose. A genetic risk score combining increasing insulin risk alleles of these four genes was associated with 53% (95% confidence interval 1.09, 2.15) increased odds of incident diabetes and 83% (95% confidence interval 1.35, 2.48) increased odds of impaired fasting glucose at follow-up. Our study uncovered novel gene-trait associations through the study of protein-coding variants and demonstrates the advantages of association screenings targeting diverse and high-risk populations to study variants absent in publicly available repositories. [ABSTRACT FROM AUTHOR]

Increasing evidence has shown that circular RNAs (circRNAs) participate in the process of cardiac remodeling. CircRNA circ_0036176 originating from the back-splicing of exon 2 to exon4 of myosin IXA (Myo9a) gene was shown to be increased in the myocardium of patients with heart failure (HF) and riched in exosomes from human AC16 cardiomyocytes with overexpression of circ_0036176. Proliferation activity was inhibited in mCFs subjected to exosomal circ_0036176 treatment and in mCFs with overexpression of circ_0036176. Interestingly, circ_0036176 contains an IRES element and an ORF of 627 nt encoding a 208-amino acid protein (termed as Myo9a-208). Myo9a-208 was shown to mediate the inhibitory effect of circ_0036176 on CFs proliferation, and miR-218-5p could inhibit Myo9a-208 expression by binding to circ_0036176, resulting in abolishing the effect of circ_0036176 on inactivating cyclin/Rb signal and suppressing CFs proliferation. Our findings suggest that circ_0036176 inhibits mCFs proliferation by translating Myo9a-208 protein to suppress cyclin/Rb pathway. [ABSTRACT FROM AUTHOR]

Southern blight, caused by Sclerotium rolfsii Sacc., is a significant disease of apple in China and many other counties. Sclerotium germination and hyphal growth are two critical processes for epidemic development. Controlled experiments were conducted to study the effects of environmental conditions on sclerotium germination and hyphal growth of the pathogen. Temperature for sclerotium germination and hyphal growth of S. rolfsii ranges from 15 to 35oC with the optimum at 31.5oC. The soil water content needs to exceed 30%, and once over this threshold, soil water content did not affect sclerotium germination and hyphal growth. The rate of sclerotium germination was high in sawdust, and hyphae grew fastest in the mixture of sawdust and soil. Sclerotium germination and hyphal growth were inhibited in nursery substrate. Hyphal growth was affected by pH but to a far lesser extent sclerotium germination. Soaking in water inhibited sclerotium germination. [ABSTRACT FROM AUTHOR]

Novel NASICON-type LiXIn0.5Z0.5(PO4)3 (X = Ti, Zr; Z = Nb, Ta) oxides were successfully synthesized by solid-state reaction, and resultant crystal structures (space group R-3c) and ionic conductivities were investigated based on a scheme of changed unit cell volume but an unchanged nominal carrier concentration (or constant Li+ amount). Relative to unsubstituted LiX2(PO4)3, the conductivities of all samples were improved by approximately an order of magnitude, with LiTiIn0.5Ta0.5(PO4)3 sample showing the highest value of 2.5×10-6 S cm-1 at room temperature. The improvement in ionic conductivity of Ti-containing samples is considered due to an increase in unit cell volume caused by the larger size of substituted ions (In3+, Nb5+, or Ta5+). Conversely, the improvement in ionic conductivity of Zr-containing samples may be attributed to an increase in lithium ion migration caused by a repulsion between the lithium ion and its surrounding cations (Zr4+, In3+, or Nb5+/Ta5+) in a smaller unit cell volume, thus forming a weakened Li-O bond. [ABSTRACT FROM AUTHOR]

Structural variations of the human brain are heritable and highly polygenic traits, with hundreds of associated genes identified in recent genome-wide association studies (GWAS). Transcriptome-wide association studies (TWAS) can both prioritize these GWAS findings and also identify additional gene-trait associations. Here we perform cross-tissue TWAS analysis of 211 structural neuroimaging and discover 278 associated genes exceeding Bonferroni significance threshold of 1.04 × 10−8. The TWAS-significant genes for brain structures have been linked to a wide range of complex traits in different domains. Through TWAS gene-based polygenic risk scores (PRS) prediction, we find that TWAS PRS gains substantial power in association analysis compared to conventional variant-based GWAS PRS, and up to 6.97% of phenotypic variance (p-value = 7.56 × 10−31) can be explained in independent testing data sets. In conclusion, our study illustrates that TWAS can be a powerful supplement to traditional GWAS in imaging genetics studies for gene discovery-validation, genetic co-architecture analysis, and polygenic risk prediction. Brain structural traits are highly heritable and have been linked to disease. Here the authors have used gene expression data to perform a transcriptome-wide association study on 211 brain structural traits, discovering 273 associated genes. [ABSTRACT FROM AUTHOR]

A total of 74 urban topsoil samples were collected from the central area of Shenyang, China. The concentration, distribution, source, and health risk of 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed. The 16 USEPA priority PAHs were detected in all soil samples. The total concentrations of PAHs ranged from 283 to 21,821 ng/g dry weight (dw), with a mean value of 2370 ng/g and median value of 1427 ng/g. The benzo[a]pyrene toxicity equivalent (BaPeq) concentrations ranged from 6.03 to 2403 ng/g dw, with a mean value of 308 ng/g and median value of 185 ng/g. High molecular weight PAHs were the predominant components. The spatial distribution revealed that soil PAH concentrations within the Two Ring Road were high, but low in the south of Hun River. Compared with other urban soils, the pollution of PAHs in urban soils of Shenyang was at a moderate level, but increased rapidly compared with previous years, especially fluoranthene. Diagnostic ratios of PAHs and positive matrix factorization model all suggested that PAHs in urban soils of Shenyang were dominantly from pyrogenic origins. The health risk assessment indicated that children had the highest total carcinogenic risk, followed by adolescents and adults. The differences between gender groups for the same age group were insignificant. Ingestion was the dominant exposure pathway, followed by dermal contact and inhalation. The total lifetime carcinogenic risks at all sampling sites were lower than the highest acceptable risk (10−4), and those of Eastern, Central, and Western Shenyang were higher than those of Northern and Southern Shenyang. [ABSTRACT FROM AUTHOR]

Purpose: Female breast cancer demonstrates bimodal age frequency distribution patterns at diagnosis, interpretable as two main etiologic subtypes or groupings of tumors with shared risk factors. While RNA-based methods including PAM50 have identified well-established clinical subtypes, age distribution patterns at diagnosis as a proxy for etiologic subtype are not established for molecular and genomic tumor classifications. Methods: We evaluated smoothed age frequency distributions at diagnosis for Carolina Breast Cancer Study cases within immunohistochemistry-based and RNA-based expression categories. Akaike information criterion (AIC) values compared the fit of single density versus two-component mixture models. Two-component mixture models estimated the proportion of early-onset and late-onset categories by immunohistochemistry-based ER (n = 2860), and by RNA-based ESR1 and PAM50 subtype (n = 1965). PAM50 findings were validated using pooled publicly available data (n = 8103). Results: Breast cancers were best characterized by bimodal age distribution at diagnosis with incidence peaks near 45 and 65 years, regardless of molecular characteristics. However, proportional composition of early-onset and late-onset age distributions varied by molecular and genomic characteristics. Higher ER-protein and ESR1-RNA categories showed a greater proportion of late age-at-onset. Similarly, PAM50 subtypes showed a shifting age-at-onset distribution, with most pronounced early-onset and late-onset peaks found in Basal-like and Luminal A, respectively. Conclusions: Bimodal age distribution at diagnosis was detected in the Carolina Breast Cancer Study, similar to national cancer registry data. Our data support two fundamental age-defined etiologic breast cancer subtypes that persist across molecular and genomic characteristics. Better criteria to distinguish etiologic subtypes could improve understanding of breast cancer etiology and contribute to prevention efforts. [ABSTRACT FROM AUTHOR]

In this study, matrix solid-phase dispersion coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the analysis of 23 organophosphate esters (OPEs) in vegetables. Under the optimal conditions, 0.5 g vegetables was dispersed with use of 2 g Florisil, 2 g anhydrous sodium sulfate, and 0.1 g graphitized carbon black, and it was transferred to an empty solid-phase extraction cartridge. The analytes were eluted with 15 mL n-hexane/acetone (1:1, v/v) and analyzed by GC-MS/MS. The method detection limits and quantitation limits ranged from 0.05 to 0.33 ng/g and from 0.16 to 1.10 ng/g, respectively. The recoveries ranged from 65.1% to 109.1%, and the relative standard deviations were less than 15%. The analysis of eight kinds of vegetables shows that the vegetables had been contaminated by OPEs; the concentrations of the sum of the OPEs ranged from 5.89 to 26.8 ng/g. The proposed method is applicable to analyze OPEs in vegetables.ᅟ [ABSTRACT FROM AUTHOR]

Seventy-four soil samples from the road greenbelts, residential areas, drylands, waste grasslands, education lands, industrial areas, city parks, and rural homesteads of Shenyang city, China, were collected and analyzed for 13 organophosphate esters (OPEs). OPEs were detected in all analyzed soil samples, which indicate that OPEs are ubiquitously environmental contaminants. The ∑13OPEs concentrations ranged from 0.039 to 0.95 mg/kg dry weight (dw), with the mean and median concentrations of 0.23 and 0.16 mg/kg dw, respectively. The pollution levels of OPEs in different land use types were different; the concentrations of OPEs in dryland soils were maximum and in city park soils were minimum. Of 13 OPEs, tri-iso-butyl phosphate (TiBP), tris-(1-chloro-2-propyl) phosphate (TCPP), tri-butoxyethyl phosphate (TBEP), and tris[2-chloro-1-(chloromethyl) ethyl] phosphate (TDCP) were the most abundant OPEs, contributing 42.0 ± 12.8, 12.4 ± 2.32, 6.31 ± 1.88, and 5.76 ± 1.86% of ∑13OPEs, respectively. Principal component analysis (PCA) and absolute principal component score-multiple linear regression (APCS-MLR) suggested that OPE pollution in soils may be derived from atmospheric deposition, road runoff and vehicular traffic emission, and wastewater/reclaimed water irrigation and sludge application, their contributions were accounting for 62.4, 17.6, and 20.0%, respectively. As compared to the results from other studies, the pollution of OPEs in the urban soils of Shenyang is relatively serious. [ABSTRACT FROM AUTHOR]

Most antibiotics were discovered by screening soil actinomycetes, but the efficiency of the discovery platform collapsed in the 1960s. By now, more than 3000 antibiotics have been described and most of the current discovery effort is focused on the rediscovery of known compounds, making the approach impractical. The last marketed broad-spectrum antibiotics discovered were daptomycin, linezolid, and fidaxomicin. The current state of the art in the development of new anti-infectives is a non-existent pipeline in the absence of a discovery platform. This is particularly troubling given the emergence of pan-resistant pathogens. The current practice in dealing with the problem of the background of known compounds is to use chemical dereplication of extracts to assess the relative novelty of a compound it contains. Dereplication typically requires scale-up, extraction, and often fractionation before an accurate mass and structure can be produced by MS analysis in combination with 2D NMR. Here, we describe a transcriptome analysis approach using RNA sequencing (RNASeq) to identify promising novel antimicrobial compounds from microbial extracts. Our pipeline permits identification of antimicrobial compounds that produce distinct transcription profiles using unfractionated cell extracts. This efficient pipeline will eliminate the requirement for purification and structure determination of compounds from extracts and will facilitate high-throughput screen of cell extracts for identification of novel compounds. [ABSTRACT FROM AUTHOR]

Three new coordination polymers, [Pb(1,3-bdc)(MOPIP)]·nHO (1), [Pb(1,4-bdc)(MOPIP)] (2) and [Pb(1,4-bdc)(MEDPQ)]·nHO (3) (MOPIP = 2-(4-methoxyphenyl)-1H-imidazo[4,5-f] [, ] phenanthroline, MEDPQ = 2-methyldipyrido [3,2-f:2′,3′-h]quinoxaline, 1,3-Hbdc = benzene-1,3-dicarboxylic acid, 1,4-Hbdc = benzene-1,4-dicarboxylic acid), have been prepared through hydrothermal reactions. The transformation of coordination modes of organic carboxylate ligands and 5,6-substituted 1,10-phen derivatives has a crucial influence on the structures of these series. In compound 1, 1,3-bdc anion adopts a chelating bidentate and bridging monodentate coordination mode, which results in a hepta-coordinated environment of Pb(II) center. However, in complex 2, 1,4-bdc anion acts in the chelating bidentate mode, which results in a hexa-coordinated environment of Pb(II) center. Complex 3 shows face-to-face π···π interactions between MEDPQ and benzene rings, which are different to that of the complexes 1 and 2. The fluorescence property and thermal stability were also investigated. [ABSTRACT FROM AUTHOR]

Abstract  Wall-associated protein kinases (WAKs) are a new group of receptor-like kinases (RLK) recently identified in Arabidopsis. A cDNA encoding a novel WAK was isolated from rice and was named OsWAK1 (Oryza sativa WAK). The deduced amino acid sequence of OsWAK1 showed 27.6% identity to WAK2 from Arabidopsis. OsWAK1 not only has the ability of autophosphorylation but also can phosphorylate OsRFP1, a putative transcription regulator recently identified in rice. OsRFP1 strongly interacts with the kinase domain of OsWAK1. This demonstrated that OsWAK1 is a functional protein kinase. A fusion protein of OsWAK1 with GFP was found to be localized on the cell surface. Plasmolysis experiments further revealed OsWAK1 is associated with the cell wall. Northern blotting analysis showed that infection of the rice blast fungus, Magnaporthe oryzae significantly induced the OsWAK1 transcripts, and the accumulation of OsWAK1 mRNA occurred earlier and was more abundant in rice leaves infected with an incompatible race than with a compatible race of the blast fungus. OsWAK1 was also induced after treatment by mechanical wounding, SA and MeJA, but not by ABA. These results imply that OsWAK1 is a novel gene involved in plant defense. Furthermore, six transgenic rice lines with constitutive expression of OsWAK1 became resistant to the compatible race. However, OsWAK1 expression was undetectable in leaves, stems and flowers but very weak in roots under normal growth conditions. This provides functional evidence that induction of OsWAK1 as a novel RLK plays important roles in plant disease resistance. [ABSTRACT FROM AUTHOR]

Shear-induced microstructures and their corresponding dynamic processes are investigated for phospholipid cylinders in aqueous solution by dissipative particle dynamic simulation. Various phospholipid cylinders with cross-sections, which are formed under shear-free flow, are selected to examine the effects of shear flow on their structures and dynamic processes. Shear flow induces the transition from cylinders into vesicles at weak rate and the transition into vesicle–lamella mixtures with increased shear rate and lamella structures at the strong shear rate. Then, the average radius of gyration and shape factors of the polymer chains in the dynamic processes are discussed in detail. Results show that shear flow causes the structure of the polymer chains to be elongated along the shear direction, and the configuration of the polymer chain can be rapidly transformed into an ellipsoid structure under strong shear. [ABSTRACT FROM AUTHOR]

This study developed a novel method for the determination of 13 organophosphate esters (OPEs) in aqueous samples through the optimization of solvent demulsification-dispersive liquid-liquid microextraction based on solidification of floating organic drop procedure coupled with ultra-high-performance liquid chromatography-tandem mass spectrometry. The proposed method was rapid and accurate and could be used in field applications. Under the most suitable conditions, the limit of detection and limit of quantification ranged from 0.16 ng/L to 20.0 ng/L and from 0.55 ng/L to 66.7 ng/L, respectively. The enrichment factors (EFs) ranged from 30 to 46. The relative standard deviations were less than 15%. The spiked recoveries ranged between 68.2% and 97.7% in the analysis of actual aqueous samples. The proposed method was convenient, environment friendly, and time and solvent saving and could be used in field applications compared with other methods. Various concentrations and types of OPEs were detected in tap water, river water, and effluent of sewage treatment plant. Effluent samples had the highest detected levels and types of OPEs. [ABSTRACT FROM AUTHOR]