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Data from A-share listed companies in Shanghai and Shenzhen stock markets, 2013–2018, was utilized in this study to explore the impact of internal control quality and analyst following on debt financing costs. A significant negative correlation was found between the quality of internal control and the costs of debt financing. Analyst following presents a substitution effect in the relationship between internal control quality and debt financing costs. The impact of analyst following and internal control quality on reducing debt financing costs also differs significantly among companies with different ownership, region, industry, and market position characteristics. These results may provide empirical data support as Chinese decision-makers improve internal control quality and optimize the investment environment to effectively mitigate the financing constraints on listed companies.

ObjectiveRecent studies have provided insights into the gut microbiota in autism spectrum disorder (ASD); however, these studies were restricted owing to limited sampling at the unitary stage of childhood. Herein, we aimed to reveal developmental characteristics of gut microbiota in a large cohort of subjects with ASD combined with interindividual factors impacting gut microbiota.DesignA large cohort of 773 subjects with ASD (aged 16 months to 19 years), 429 neurotypical (NT) development subjects (aged 11 months to 15 years) were emolyed to determine the dynamics change of gut microbiota across different ages using 16S rRNA sequencing.ResultIn subjects with ASD, we observed a distinct but progressive deviation in the development of gut microbiota characterised by persistently decreased alpha diversity, early unsustainable immature microbiota, altered aboudance of 20 operational taxonomic units (OTUs), decreased taxon detection rate and 325 deregulated microbial metabolic functions with age-dependent patterns. We further revealed microbial relationships that have changed extensively in ASD before 3 years of age, which were associated with the severity of behaviour, sleep and GI symptoms in the ASD group. This analysis demonstrated that a signature of the combination of 2 OTUs, Veillonella and Enterobacteriaceae, and 17 microbial metabolic functions efficiently discriminated ASD from NT subjects in both the discovery (area under the curve (AUC)=0.86), and validation 1 (AUC=0.78), 2 (AUC=0.82) and 3 (AUC=0.67) sets.ConclusionOur large cohort combined with clinical symptom analysis highlights the key regulator of gut microbiota in the pathogenesis of ASD and emphasises the importance of monitoring and targeting the gut microbiome in future clinical applications of ASD.

An in-situ approach is described for synthesis of poly(sulfobetaine-co-polyhedral oligomeric silsesquioxane) [poly(sulfobetaine-co-POSS)] that can be used in a hybrid monolithic column as a hydrophilic liquid chromatography (HILIC) stationary phase. Synthesis involves (a) radical polymerization of octa(propyl methacrylate)-polyhedral oligomeric silsesquioxane (MA-POSS) and organic monomers such as dimethylaminopropyl methacrylate or vinyl imidazole, and (b) in-situ ring-opening quaternization between 1,4-butane sultone and the organic monomers. The sulfobetaine groups are generated in-situ monolith. This obviates the need for synthesis of sulfobetaine monomer previously. The pore size and permeability of the material can be tuned by using a binary porogenic system (polyethyleneglycol 600 and acetonitrile) and via the composition of the polymerization mixture. The optimized hybrid monolith owns its merits to the presence of POSS and sulfobetaine groups with good mechanical stability, the lack of residual silanol groups, and adequate hydrophilicity. The column filled with the monoliths was evaluated as a stationary phase for HILIC. Several kinds of polar compounds (including nucleosides, bases, phenols, aromatic acids and amides) were separated by using mobile phases with high organic solvent fractions in capillary liquid chromatography. Graphical abstractAn in-situ approach is described for synthesis of poly(sulfobetaine-co-polyhedral oligomeric silsesquioxane) hybrid monolithic column for use in hydrophilic liquid chromatography. The optimized monolith owns good mechanical stability, the lack of residual silanol groups and adequate hydrophilicity. Baseline separation of several kinds of polar compounds is achieved on the column. MA-POSS: octa(propyl-methacrylate) polyhedral oligomeric silsesquioxane; DMAEMA: dimethylaminoethyl methacrylate; AIBN: azodiisobutyronitrile. Poly(DMABS-co-POSS): poly(N-(4-sulfobutyl)-N-methacryloxypropyl- N,N-dimethylammonium-betaine-co-polyhedral oligomeric silsesquioxane).

To investigate the emotional problems (depressive and anxiety symptoms) of mothers of children with autism spectrum disorder (ASD) and explore the role of the mother's socioeconomic status (SES) and the core symptoms of the child on the mother's emotional problems. This cross-sectional survey was performed in 180 mothers of children with ASD in Chang Sha city of China. The 7-item Generalized Anxiety Disorder Scale (GAD-7) and the 9-item Patient Health Questionnaire (PHQ-9) were used to assess the anxiety and depressive symptoms of the mothers of the autistic children. The education level and annual family income, as well as occupation, were be selected as components of the mother's SES. Autism Behaviour Checklist (ABC) and Social Responsiveness Scale (SRS) were used for the evaluation of the core symptoms of the children. A general information questionnaire was also used. The ordinal regression was used to examine the effect of the SES and children's core symptoms on maternal emotional problems. The valid response rate was 92.7% (167 of 180 questionnaires were returned). Of the mothers studied, 72.5% and 80.2% had depressive and anxiety symptoms, respectively, and 67.1% suffered from both symptoms. Mother's SES was observed to be unrelated to maternal anxiety symptoms (P >.05). Only 1 component of the SES (junior high school education level) was related to depressive symptoms (OR = 0.31, 95% CI 0.12–0.80). SRS score under 115 (OR = 0.38, 95% CI 0.16–0.93) of autistic children was a protective factor against maternal anxiety symptoms. The borderline and mild behavioral problems (OR = 0.43, 95% CI 0.19–0.99; OR = 0.45, 95% CI 0.22–0.94, respectively) of autistic children were protective factors against maternal depressive symptoms. Mothers of autistic children generally exhibited high levels of anxiety and depressive symptoms. The core symptoms of the autistic children were observed to be strongly associated with both maternal anxiety and depressive symptoms. Improvements in the core symptoms of children with ASD may help reduce maternal anxiety and depressive symptoms to some extent.

Background.There has been significant research on the genetic and environmental factors of congenital heart defects (CHDs), but few causes of teratogenicity, especially teratogenic mechanisms, can be clearly identified. Metabolomics has a potential advantage in researching the relationship between external factors and CHD.Objective.To find and identify the urinary potential biomarkers of pregnancy (including in the second and third trimesters) for fetuses with CHD based on modified gas chromatograph-mass spectrometer (GC-MS), which could reveal the possibility of high-risk factors for CHD and lay the foundation for early intervention, treatment, and prevention.Methods.Using a case-control design, we measured the urinary potential biomarkers of maternal urine metabolomics based on GC-MS in a population-based sample of women whose infants were diagnosed with CHD (70 case subjects) or were healthy (70 control subjects). SIMCA-P 13.0 software, principal component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA), Wilcoxon-Mann-Whitney test, and logistics regression were used to find significant potential biomarkers.Result.The 3D score graph of the OPLS-DA showed that the CHD and control groups were fully separated. The fitting parameters were R2x=0.78 and R2y=0.69, and the forecast rate was Q2=0.61, indicating a high forecast ability. According to the ranking of VIPs from the OPLS-DA models, we found 34 potential metabolic markers with a VIP > 1, and after two pairwise rank sum tests, we found 20 significant potential biomarkers, which were further used in multifactor logistic regressions. Significant substances, including 4-hydroxybenzeneacetic acid (OR=4.74, 95% CI: 1.06-21.06), 5-trimethylsilyloxy-n-valeric acid (OR=15.78, 95% CI: 2.33-106.67), propanedioic acid (OR=5.37, 95% CI: 1.87-15.45), hydracrylic acid (OR=6.23, 95% CI: 1.07-36.21), and uric acid (OR=5.23, 95% CI: 1.23-22.32), were associated with CHD.Conclusion.The major potential biomarkers in maternal urine associated with CHD were 4-hydroxybenzeneacetic acid, 5-trimethylsilyloxy-n-valeric acid, propanedioic acid, hydracrylic acid, and uric acid, respectively. These results indicated that the short chain fatty acids (SCFAs) and aromatic amino acid metabolism may be relevant with CHD.

Autism spectrum disorders (ASD) are a highly heterogeneous group of neurodevelopmental disorders that are more commonly diagnosed in boys than in girls. The reasons for gender differences in ASD are unknown and no definitive current evidence can explain male predominance. Therefore, in search for laboratory biomarkers responsible for ASD, a comprehensive metabolomics study was performed by metabolic profiling of urine samples in 51 ASD subjects and 51 age- and sex-matched children with typical development. Orthogonal partial least-squares discriminant analysis (OPLS-DA) models with poor quality failed to perform the analysis based on gender in the ASD and control groups. OPLS-DA models based on single-sex samples, especially in female subjects, had better clustering between the ASD and control groups with an increase in the R2 and Q2 values compared with those in the whole group. Significantly increased levels of adenine, 2-Methylguanosine, creatinine, and 7alpha-hydroxytestololactone and a decrease in creatine were observed in the female ASD subjects. In particular, 7alpha-hydroxytestololactone, which has a structure similar to that of testolactone, was positively correlated with adenine (Pearson correlation coefficient, r = 0.738, p

Autism spectrum disorders (ASDs) are a group of mental illnesses highly correlated with gut microbiota. Recent studies have shown that some abnormal aromatic metabolites in autism patients are presumably derived from overgrownClostridiumspecies in gut, which may be used for diagnostic purposes. In this paper, a GC/MS based metabolomic approach was utilized to seek similar biomarkers by analyzing the urinary information in 62 ASDs patients compared with 62 non-ASDs controls in China, aged 1.5–7. Three compounds identified as 3-(3-hydroxyphenyl)-3-hydroxypropionic acid (HPHPA), 3-hydroxyphenylacetic acid (3HPA), and 3-hydroxyhippuric acid (3HHA) were found in higher concentrations in autistic children than in the controls (p<0.001). After oral vancomycin treatment, urinary excretion of HPHPA (p<0.001), 3HPA (p<0.005), and 3HHA (p<0.001) decreased markedly, which indicated that these compounds may also be from gutClostridiumspecies. The sensitivity and specificity of HPHPA, 3HPA, and 3HHA were evaluated by receiver-operating characteristic (ROC) analysis. The specificity of each compound for ASDs was very high (>96%). After two-regression analysis, the optimal area under the curve (AUC, 0.962), sensitivity (90.3%), and specificity (98.4%) were obtained by ROC curve of Prediction probability based on the three metabolites. These findings demonstrate that the measurements of the three compounds are strong predictors of ASDs and support the potential clinical utility for identifying a subgroup of ASDs subjects.

Experiments employing a technique involving solvent extraction and gas chromatography–mass spectrometry (GC–MS) analysis were conducted to investigate the distributions and transfer behavior of alkalescent flavors in moderate/low-tar cigarettes. In the current study, the transfer behavior of eleven flavors, including two alkalescent ketones, eight heterocyclic compounds, and perillartine, were evaluated by examining their retention ratios in tobacco (%r 1), their ratios of immigration into the filter tip (%r 2), their transfer ratios into the mainstream smoke (%r 3), and their ratios of interception by the filter tip (%r 4), which varied from 3.94 to 44.10, from 0 to 35.36, from 0 to 17.14, and from 7.36 to 50.53 %, respectively. The analytical results indicated that flavor transfer behavior is likely dependent on the molecular weight and boiling point of the flavor, the configuration of the cigarette, and/or other factors (e.g., intermolecular tension, chemical polarity, etc.), although no further studies of these aspects were performed as part of this work. These findings may lead to improvements in the flavoring procedure during the future development of novel cigarettes.

A novel construction strategy of monolithic capillary column for selectively enriching perfluorinated persistent organic pollutants was proposed. The organic-inorganic hybrid fluorous monolithic capillary column was synthesized by a "one-pot" approach via the polycondensation of γ-methacryloxypropyltrimethoxy-silane, then in situ copolymerization of 1H,1H,7H-dodecafluoroheptyl methacrylate and vinyl group on the precondensed siloxanes. The obtained monolithic columns were systematically characterized. The results demonstrated that the optimal column possessed good mechanical stability and high permeability. The adsorption capacities of the optimized monolithic column for perfluorooctanoic acid and perfluorooctane sulfonate were 0.257 and 0.513 μg/mg, respectively. Adsorption capacities of the monoliths were proved to increasing with increasing the amounts of fluorinated monomers in the fluorous monoliths. Sodium 1-octanesulfonate, as a comparison compound, was hardly adsorbed on the fluorous monolith. In addition, the trace amounts of perfluorooctanoic acid and perfluorooctane sulfonate in water samples can be successfully concentrated about 160 times to their original concentrations by this monolithic column. These results demonstrated that the capacity and selectivity of the affinity fluorous column is high and can be applied to the selective enrichment for the perfluorinated persistent organic pollutants from environmental samples.

A facile, flexible process was developed for the preparation of surface-glycosylated porous monolithic columns via aqueous two-phase graft copolymerization of polyethylene glycol diacrylate (PEGDA) and water-soluble dextran (dextran sulfate). The formation of poly(PEGDA) porous skeletons and surface glycosylation were achieved via a one-step process without pre-modification of the dextran. The synthesis conditions were thoroughly optimized. The optimal monolithic column exhibited a large dry state surface area (greater than 400 m2/g), and it was evaluated as a hydrophilic liquid chromatography (HILIC) stationary phase. A typical HILIC mechanism was observed at high organic solvent content (≥65% acetonitrile). In addition, the resulting monolithic column demonstrated the potential use in analysis of complex biological sample and enviroment water.

Although the phenylalanine/tyrosine ratio in blood has been the gold standard for diagnosis of phenylketonuria (PKU), the disadvantages of invasive sample collection and false positive error limited the application of this discriminator in the diagnosis of PKU to some extent. The aim of this study was to develop a new standard with high sensitivity and specificity in a less invasive manner for diagnosing PKU. In this study, an improved oximation-silylation method together with GC/MS was utilized to obtain the urinary metabolomic information in 47 PKU patients compared with 47 non-PKU controls. Compared with conventional oximation-silylation methods, the present approach possesses the advantages of shorter reaction time and higher reaction efficiency at a considerably lower temperature, which is beneficial to the derivatization of some thermally unstable compounds, such as phenylpyruvic acid. Ninety-seven peaks in the chromatograms were identified as endogenous metabolites by the National Institute of Standards and Technology (NIST) mass spectra library, including amino acids, organic acids, carbohydrates, amides, and fatty acids. After normalization of data using creatinine as internal standard, 19 differentially expressed compounds with p values of

A monolithic column with high affinity to fluorous compounds was prepared using a polyhedral oligomeric silsesquioxane (POSS) reagent as the cross-linker and pentadecafluorooctyl methacrylate (PDFOMA) as the functionality monomer. The pore properties and permeability could be tuned by the composition of the polymerization mixture. The characterization and evaluation results revealed that the obtained POSS-PDFOMA hybrid monolith owned the merits of POSS and PDFOMA with good mechanical stability, no residual silanol and high affinity to fluorous compounds. A series of perfluoroalkyl methacrylates were baseline resolved on the optimized monolithic column under isocratic elution of 70% acetonitrile aqueous solution. Such a resolution could not be achieved on a silica-based C18 monolithic column. A column efficiency of 30000N/m was observed. In addition, several perfluoroalkyl sulfonates were also baseline separated on the fluorous monolith applying 0.1% (v/v) acetic acid aqueous solution containing 75% acetonitrile as mobile phase without the addition of ammonium.

A novel construction strategy of monolithic capillary column for selectively enriching perfluorinated persistent organic pollutants was proposed. The organic-inorganic hybrid fluorous monolithic capillary column was synthesized by a "one-pot" approach via the polycondensation of γ-methacryloxypropyltrimethoxy-silane, then in situ copolymerization of 1H,1H,7H-dodecafluoroheptyl methacrylate and vinyl group on the precondensed siloxanes. The obtained monolithic columns were systematically characterized. The results demonstrated that the optimal column possessed good mechanical stability and high permeability. The adsorption capacities of the optimized monolithic column for perfluorooctanoic acid and perfluorooctane sulfonate were 0.257 and 0.513 μg/mg, respectively. Adsorption capacities of the monoliths were proved to increasing with increasing the amounts of fluorinated monomers in the fluorous monoliths. Sodium 1-octanesulfonate, as a comparison compound, was hardly adsorbed on the fluorous monolith. In addition, the trace amounts of perfluorooctanoic acid and perfluorooctane sulfonate in water samples can be successfully concentrated about 160 times to their original concentrations by this monolithic column. These results demonstrated that the capacity and selectivity of the affinity fluorous column is high and can be applied to the selective enrichment for the perfluorinated persistent organic pollutants from environmental samples.