HFSCCD: A Hybrid Neural Network for Fetal Standard Cardiac Cycle Detection in Ultrasound Videos.

In the fetal cardiac ultrasound examination, standard cardiac cycle (SCC) recognition is the essential foundation for diagnosing congenital heart disease. Previous studies have mostly focused on the detection of adult CCs, which may not be applicable to the fetus. In clinical practice, localization of SCCs needs to recognize end-systole (ES) and end-diastole (ED) frames accurately, ensuring that every frame in the cycle is a standard view. Most existing methods are not based on the detection of key anatomical structures, which may not recognize irrelevant views and background frames, results containing non-standard frames, or even it does not work in clinical practice. We propose an end-to-end hybrid neural network based on an object detector to detect SCCs from fetal ultrasound videos efficiently, which consists of 3 modules, namely Anatomical Structure Detection (ASD), Cardiac Cycle Localization (CCL), and Standard Plane Recognition (SPR). Specifically, ASD uses an object detector to identify 9 key anatomical structures, 3 cardiac motion phases, and the corresponding confidence scores from fetal ultrasound videos. On this basis, we propose a joint probability method in the CCL to learn the cardiac motion cycle based on the 3 cardiac motion phases. In SPR, to reduce the impact of structure detection errors on the accuracy of the standard plane recognition, we use XGBoost algorithm to learn the relation knowledge of the detected anatomical structures. We evaluate our method on the test fetal ultrasound video datasets and clinical examination cases and achieve remarkable results. This study may pave the way for clinical practices.

The association between childhood adiposity in northeast China and anthropogenic heat flux: A new insight into the comprehensive impact of human activities.

Anthropogenic heat has been reported to have significant health impacts, but research on its association with childhood adiposity is still lacking. In this study, we matched the 2008-2012 average anthropogenic heat flux, as simulated by a grid estimation model using inventory methods, with questionnaire and measurement data of 49,938 children randomly recruited from seven cities in Northeast China in 2012. After adjusting for social demographic and behavioral factors, we used generalized linear mixed-effect models to assess the association between anthropogenic heat flux and adiposity among children. We also examined the effect modification of various social demographic and behavioral confounders. We found that each 10 W/m2 increase in total anthropogenic heat flux and that from the industry source was associated with an increase of 5.82% (95% CI = 0.84%-11.05%) and 6.62% (95% CI = 0.87%-12.70%) in the odds of childhood adiposity. Similarly, the excess rate of adiposity among children were 5.26% (95% CI = -1.33%-12.29%) and 8.51% (95% CI = 2.24%-15.17%) per 1 W/m2 increase in the anthropogenic heat flux from transportation and buildings, and was 7.94% (95% CI = 2.28%-13.91%) per 0.001 W/m2 increase in the anthropogenic heat flux from human metabolism. We also found generally greater effect estimates among female children and children who were exposed to passive smoking during pregnancy, born by caesarean section, non-breastfed/mixed-fed, or lived within 20 m adjacent to the main road. The potential deleterious effect of anthropogenic heat exposure on adiposity among children may make it a new but major threat to be targeted by future mitigation strategies.

Direct Identification and Quantitation of Protein Peptide Powders Based on Multi-Molecular Infrared Spectroscopy and Multivariate Data Fusion.

Given that protein peptide powders (PPPs) from different biological sources were inherited with diverse healthcare functions, which aroused adulteration of PPPs. A high-throughput and rapid methodology, united multi-molecular infrared (MM-IR) spectroscopy with data fusion, could determine the types and component content of PPPs from seven sources as examples. The chemical fingerprints of PPPs were thoroughly interpreted by tri-step infrared (IR) spectroscopy, and the defined spectral fingerprint region of protein peptide, total sugar, and fat was 3600-950 cm-1, which constituted MIR finger-print region. Moreover, the mid-level data fusion model was of great applicability in qualitative analysis, in which the F1-score reached 1 and the total accuracy was 100%, and a robust quantitative model was established with excellent predictive capacity (Rp: 0.9935, RMSEP: 1.288, and RPD: 7.97). MM-IR coordinated data fusion strategies to achieve high-throughput, multi-dimensional analysis of PPPs with better accuracy and robustness which meant a significant potential for the comprehensive analysis of other powders in food as well.

Associations between maternal complications during pregnancy and childhood asthma: a retrospective cohort study.

Background: Studies on the associations between maternal complications during pregnancy and childhood asthma are exclusively conducted in Western countries. The findings are mixed and may not be translated to other populations. We aimed to investigate the associations among the Chinese population and to determine whether the associations were mediated through pre-term birth, caesarean delivery, low birthweight and not breastfeeding in the first 6 months. Methods: We conducted a retrospective cohort study of 166 772 children in Guangzhou, China. Information on maternal gestational hypertension, gestational diabetes and gestational anaemia during pregnancy was extracted from medical records. Ever-diagnosis of asthma in children aged 6-12 years was obtained by questionnaire. Logistic regression models and mediation analyses were used to estimate the adjusted odds ratios (aORs) and 95% confidence intervals for childhood asthma. Results: Gestational hypertension, gestational diabetes and gestational anaemia during pregnancy were associated with an increased risk of ever-diagnosed childhood asthma: aOR 1.48 (95% CI 1.37-1.60), 1.71 (95% CI 1.65-1.78) and 1.34 (95% CI 1.26-1.45), respectively. A stronger association was observed for two or three gestational complications (aOR 2.02 (95% CI 1.93-2.16)) than one gestational complication (aOR 1.64 (95% CI 1.52-1.77)). The aOR for the three gestational complications was 1.35 (95% CI 1.26-1.45), 1.63 (95% CI 1.58-1.70) and 1.32 (95% CI 1.24-1.43), respectively, after controlling for the mediators, including pre-term birth, caesarean delivery, low birthweight and not breastfeeding in the first 6 months. Conclusions: Gestational hypertension, gestational diabetes and gestational anaemia were associated with childhood asthma, and the associations were partially explained by the mediation effects.

Research of the Active Components and Potential Mechanisms of Qingfei Gujin Decoction in the Treatment of Osteosarcoma Based on Network Pharmacology and Molecular Docking Technology.

Aim: Qingfei Gujin Decoction (QGD) has been shown to be effective against osteosarcoma. This research was aimed at investigating the main active ingredients and potential mechanisms of QGD acting on osteosarcoma through network pharmacology and molecular docking techniques. Methods: The active ingredients and targets of QGD were screened from the TCMSP database, and the predicted targets were obtained from the PharmMapper database. Meanwhile, the targets of osteosarcoma were collected using OMIM, PharmGKB, and DisGeNET databases. Then, GO and KEGG enrichment analyses were performed by RStudio. PPI and drug-ingredient-target networks were constructed using Cytoscape 3.2.1 to screen the major active ingredients, key networks, and targets. Finally, molecular docking of key genes and their regulatory active ingredients was performed using AutoDockTools 1.5.6 software. Results: 38 active ingredients were collected, generating 89 cross-targets; quercetin, luteolin, ß-sitosterol, and kaempferol were the main active ingredients of QGD acting on osteosarcoma, and major signaling pathways such as PI3K-Akt signaling pathway, MAPK signaling pathway, and IL-17 signaling pathway were observed. TP53, SRC, and ESR1 were identified as key proteins that docked well with their regulated compounds. Conclusion: QGD is effective against osteosarcoma through multicomponent, multitarget, and multipathway. This study was helpful for finding effective targets and compounds for osteosarcoma treatment.

A robust, flexible adhesive tape-based SERS substrate fabricated by polymer etching and subsequent Au coating on the exposed SiO2 nanosphere monolayer.

With the rapid development of trace detection, high-performance flexible surface-enhanced Raman scattering (SERS) substrates have enjoyed steady growth of interest. In this paper, a facile method to improve the robustness of the flexible SERS substrate via the synergistic effect of rigid SiO2 nanospheres and flexible tape was demonstrated for the first time. In detail, the spin-coated SiO2 nanosphere monolayer was transferred from the host silicon wafer into the tape by peeling-off process, followed by O2 plasma etching of tape polymer to expose the nanospheres, and final Au coating to form plentiful SERS "hotspots". The as-prepared SERS sample shows a detection limit of Rhodamine 6G (R6G) down to 10-10 M and can afford a 500 times bending-releasing cyclic test. Our research provides a promising strategy to prepare robust SERS substrates which exhibit good potential in practical molecule detection on curved surfaces.

Kinetics and mechanisms for sulfamethoxazole transformation in the phenolic acid-laccase (Trametes versicolor) system.

Oxidation of phenolic acids (PCs) by laccase could produce various kinds of reactive oxygen species (ROS), which is expected to have substantial impact on the transformation of antibiotics like sulfamethoxazole (SMX) in soil and aquatic environments. In this study, the formation of semiquinones radical (SQ●-), superoxide anion radical (O2●-), hydrogen peroxide (H2O2), hydroxyl radical (●OH), and singlet oxygen (1O2) in a laccase-gallic acid (GA) reaction system was confirmed. Meanwhile, GA would be transformed to its monomeric quinone and quinones of di- and tri-polymers. Transformation of SMX by laccase alone is negligible, while which was greatly enhanced in the presence of GA at the optimal pH of 5.5. The dissolved O2 was the requisite for transformation of SMX due to its fundamental role in the formation of SQ●-, the key species initializing the chain reactions for the generation of other ROS. The quenching experiments indicated O2●- and 1O2 were the main ROS responsible for SMX transformation. A total of thirteen products were proposed for the SMX transformation, with the pathways including the breaking of S-N bond, the cleavage of oxazole ring, electrophilic substitution, Michael addition, and condensation reactions. Moreover, the existence of electron-withdrawing substitution group on the benzene ring of PCs and less stability of SQ●- was believed to be favorable for the transformation of SMX. The results above expand our understanding on the role of oxidation of PCs by laccase in the SMX transformation in environments and are of significance in relation to use of laccase in dealing with SMX pollution.

Enhanced transformation of sulfamethoxazole by birnessite in the presence of gallic acid: Kinetics and pathways.

The emergence of antibiotic agents like sulfamethoxazole (SMX) in soils and surface water can cause serious threat to human and animal health. In this work, mechanisms for the promotive effect of gallic acid (GA) on the transformation of SMX by birnessite were studied. In the absence of GA, the observed pseudo-first-order reaction constants (kobs) decreased as the pH increased from 4.0 to 8.0, in agreement with the decrease in redox potential of birnessite with increasing pH. The changes in chemical state of surface Mn atoms suggested that Mn(IV) played a major role in SMX transformation. SMX was transformed mainly by the bond cleavage of SN and SC, NH oxidation, and self- or cross-coupling reactions, with the formation of seven transformation products. The presence of GA could significantly promote the transformation of SMX, which was more pronounced at pH 6.0 comparing to the effect observed at 4.0. This promotive effect was attributed to both the addition reactions between SMX and GA quinones and the condensation reactions between -COOH of quinones and -NH2 of SMX or its transformation products. Moreover, the addition reaction between SMX and OH coming from the GA oxidation by birnessite was also proposed, while its contribution to SMX transformation was small. Furthermore, pyrogallol and methyl gallate that do not contain electron-withdrawing substituent like -COOH group are less effective in promoting SMX transformation than GA, suggesting the electron-density of ß­carbon is key to the occurrence of addition reaction. Our results demonstrate the important role of birnessite and naturally occurring phenolic acids in abiotic transformation SMX, which will profoundly affect its mobility and bioavailability in environments.

Association between maternal pre pregnancy and pre delivery overweight with overweight and obesity of middle school students:a case control study / 中国学校卫生

Objective@#To explore the association between maternal pre pregnancy and pre delivery overweight with overweight and obesity among offspring during adolescence in Guangzhou, and to provide evidence for child obesity prevention.@*Methods@#Based on the routine physical examination of primary and secondary school students in Guangzhou, random sampling was used to 6 middle schools and questionnaire survey was conducted among 3 384 students and their parents. Students with overweight and obesity were included in the case group, and the other students were included in the control group. Propensity Score Matching (PSM) was adopted to reduce selection bias. Logistic regression model and χ 2 test were used to analyze the data before and after PSM.@*Results@#The result of univariate analysis showed that there were statistically significant differences between overweight/obese group and the control group by gender, schooling stage (middle and high schools), picky eater, family history of obesity, family monthly income, delivery mode, high birthweight, and gestational weight gain before PSM( χ 2=42.38, 10.64, 14.47, 26.85, 10.58, 13.59 , 15.53, 20.64, P <0.05). After PSM, results showed that there were no statistically significant differences between overweight/obese group and the control group in middle and high schools, and mother delivery mode( P >0.05). Logistic regression analysis showed that the risk of overweight and obesity of maternal pre pregnancy on adolescent offspring was 1.54 times higher than control group (95% CI =1.01-2.36) before PSM, and the overweight and obesity of maternal predelivery also increased the risk of overweight and obesity of adolescent offspring( OR=2.35, 95%CI =1.67-3.31). After PSM, maternal overweight and obesity pre pregnancy ( OR=2.17, 95%CI =1.41-3.34) and maternal overweight and obesity pre delivery( OR=2.99, 95%CI =2.08-4.31) significantly increased the risk of overweight and obesity in adolescent offspring.@*Conclusion@#Maternal overweight and obesity pre pregnancy and pre delivery are associated with increased risk of overweight and obesity in adolescent offspring.

Impact of gestational complications on adolescent depression / 中国学校卫生

Objective@#To investigate the incidence of adolescent depressive symptoms in primary and secondary schools in Guangzhou and the effect of gestational complications on adolescent depression, so to provide scientific basis for depression prevention among adolescent.@*Methods@#Stratified cluster random sampling method was used to select 808 primary and secondary schools in 11 districts of Guangzhou. A total of 96 756 parents of adolescents aged 10-20 were surveyed for adolescents depressive symptoms and maternal gestational complications.@*Results@#The parental reported rates of mild, moderate and major depressive symptoms of adolescents were 5.5%, 3.5%, and 0.5%, respectively. Univariate analysis showed that the severity of adolescent depression symptoms had statistical significance with maternal gestational hypertension, gestational diabetes mellitus, cholestasis, hypothyroidism, hyperthyroidism, gestational anemia and viral hepatitis ( χ 2=12.42~158.91， P <0.01). Multivariate Logistic regression showed that maternal gestational diabetes mellitus ( OR =1.41, 95% CI =1.18- 1.68 ), hypothyroidism during pregnancy ( OR =1.61, 95% CI = 1.15-2.26), and hyperthyroidism during pregnancy ( OR =1.40, 95% CI =1.03-1.91), anemia during pregnancy ( OR = 1.46 , 95% CI =1.35-1.59), and viral hepatitis during pregnancy ( OR =1.67, 95% CI =1.38-2.02) were positively correlated with the severity of adolescent depression symptoms reported by parents( P <0.05).@*Conclusion@#Gestational diabetes mellitus, gestational hypothyroidism, gestational hyperthyroidism, gestational anemia and gestational viral hepatitis are associated with adolescent depressive symptom.

Degradation of sulfamethoxazole by the heterogeneous Fenton-like reaction between gallic acid and ferrihydrite.

In soils, the Fenton-like reaction can be initiated when phenolic acids (PCs) existed simultaneously with iron oxides and dissolved O2, which would have great impact on transformation of organic pollutants. This study probed the mechanism of the Fenton-like reaction that occurs in a heterogeneous system containing ferrihydrite (Fh) and gallic acid (GA), and evaluated its performance in sulfamethoxazole (SMX) degradation. In the absence of dissolved O2, only reductive dissolution of Fh by GA occurred. It was further showed that Fh is capable of catalyzing the oxidation of GA by O2, in which the Fenton-like reaction was involved with the formation of reactive oxygen species (ROS) (semiquinone free radicals, superoxide, singlet oxygen, hydroxyl radical and H2O2) together with the adsorbed and aqueous Fe(II). At pH 4.0, this Fenton-like reaction could lead to SMX degradation at a rate of 38.2% and 65.6% when GA concentration were set at 0.1 and 0.2 mM, respectively. Elevating pH inhibited SMX degradation process. Citric acid had no effect on SMX degradation, while ascorbic acid showed a promotive effect. Moreover, HPLC-MS showed the presence of 12 intermediate products, and the proposed pathways for SMX degradation included cleavage, demethylation, oxidation and electrophilic substitution. This work could enhance our understanding on how the abiotic soil Fenton-like reaction controls the fate of SMX in soil environments.

Comprehensive Analysis of a circRNA-miRNA-mRNA Network to Reveal Potential Inflammation-Related Targets for Gastric Adenocarcinoma.

Gastric cancer (GC) is the most common malignancy of the stomach. This study was aimed at elucidating the regulatory network of circRNA-miRNA-mRNA and identifying the precise inflammation-related targets in GC. The expression profiles of GSE83521, GSE78091, and GSE33651 were obtained from the GEO database. Interactions between miRNAs and circRNAs were investigated by the Circular RNA Interactome, and targets of miRNAs were predicted with miRTarBase. Then, a circRNA/miRNA/mRNA regulatory network was constructed. Also, functional enrichment analysis of selected differentially expressed genes (DEGs) was performed. The inflammation-/GC-related targets were collected in the GeneCards and GenLiP3 database, respectively. And a protein-protein interaction (PPI) network of DE mRNAs was constructed with STRING and Cytoscape to identify hub genes. The genetic alterations, neighboring gene networks, expression levels, and the poor prognosis of hub genes were investigated in cBioPortal, Oncomine, and Human Protein Atlas databases and Kaplan-Meier plotter, respectively. A total of 10 DE miRNAs and 33 DEGs were identified. The regulatory network contained 26 circRNAs, 10 miRNAs, and 1459 mRNAs. Functional enrichment analysis revealed that the selected 33 DEGs were involved in negative regulation of fat cell differentiation, response to wounding, extracellular matrix- (ECM-) receptor interaction, and regulation of cell growth pathways. THBS1, FN1, CALM1, COL4A1, CTGF, and IGFBP5 were selected as inflammation-related hub genes of GC in the PPI network. The genetic alterations in these hub genes were related to amplification and missense mutations. Furthermore, the genes RYR2, ERBB2, PI3KCA, and HELZ2 were connected to hub genes in this study. The hub gene levels in clinical specimens were markedly upregulated in GC tissues and correlated with poor overall survival (OS). Our results suggest that THBS1, FN1, CALM1, COL4A1, CTGF, and IGFBP5 were associated with the pathogenesis of gastric carcinogenesis and may serve as biomarkers and inflammation-related targets for GC.

Adsorption and reduction of Cr(VI) by hydroxylated multiwalled carbon nanotubes: effects of humic acid and surfactants.

The present study investigated the impacts of humic acid (HA) and surfactants (SDBS and CTAB), which were ubiquitously found in the aquatic environments, on the removal of Cr(VI) by the hydroxylated MWCNTs-OH. The results showed that MWCNTs-OH could remove Cr(VI) from aqueous solution via adsorption coupled with reduction, and the kinetics followed the pseudo-first-order model with the rate of 3.5 × 10-3 h-1. In the presence of anionic SDBS, the removal percentage of Cr(VI) was greatly inhibited because the hydrophobic interaction and π-π interaction between SDBS and MWCNTs-OH surfaces not only decreased the adsorption sites for Cr(VI) but also made the surfaces more negatively charged. On the contrary, the existence of cationic CTAB could lead to the surfaces more positively charged, which consequently enhance the electrostatic attraction between Cr(VI) and the surfaces as well as the removal of Cr(VI). Noticeably, the presence of HA could promote the removal of Cr(VI), which was attributed to the reduction of Cr(VI) by the adsorbed HA. The ESR spectra indicated the existence of π-type radicals in HA structure and conduction electrons in MWCNTs-OH, and then the π-π interaction between MWCNTs-OH and adsorbed HA possibly increase the electron-donating ability of HA. Moreover, the promotive effect of HA could be enhanced with the addition of Ca2+. This study was helpful for us to understand the role of MWCNTs-OH in controlling the fate of Cr(VI) when HA and surfactants were present.

Associations of Circulating Irisin Concentrations With Cardiometabolic Risk Factors Among Children Vary by Physical Activity or Sedentary Time Levels.

Whether irisin concentrations are associated with physical activity (PA) and sedentary time (ST) remains unknown. The role of irisin on cardiometabolic health among children has been contradictory and scarce. This study aimed to examine associations of PA and ST with irisin concentrations and relationships between irisin concentrations and cardiometabolic parameters among children. Additionally, we assessed the interaction between PA or ST and irisin concentrations on cardiometabolic parameters. Basing on a cross-sectional survey of 3,651 general children aged 7-12 years, 575 with different self-reported PA (moderate-vigorous intensity PA ≥ 60 min/day or <150 min/week) and ST (gender-, age-specific ST ≥ 75% or <25% percentile) levels were selected. PA and ST were assessed by the validated international physical activity questionnaires. Fasting blood glucose and lipid profile levels were measured with standard methods by biochemistry analyzer. Plasma irisin concentrations were measured by ELISA. The associations of PA and ST with circulating irisin concentrations were examined by linear regression. Linear regression analysis was also used to estimate associations of circulating irisin concentrations with cardiometabolic variables. Interactions between PA or ST and irisin concentrations on cardiometabolic parameters were calculated using multiple linear regression models with dichotomized factors (low PA and high PA; low ST and high ST). No significant association was observed between circulating irisin concentrations and habitual PA or ST. Irisin concentrations were negatively associated with body mass index (BMI) (ß = -0.220), BMI z-score (ß = -0.098), waist circumference (ß = -0.621), diastolic blood pressure (DBP) (ß = -0.561), and triglyceride (ß = -0.019) in low PA subgroup, and negatively related to fasting blood glucose (ß = -0.040) among high PA subgroup. Moreover, irisin concentrations were negatively associated with BMI (ß = -0.157) and fasting blood glucose (ß = -0.026) only in high ST subgroup (all P < 0.05). We also observed a significant interaction between PA and irisin concentrations on BMI (P interaction = 0.0350), BMI z-score (P interaction = 0.0173), and DBP (P interaction = 0.0068). In summary, irisin concentrations were not associated with habitual PA or ST in children. The negative associations of irisin concentrations with BMI, BMI z-score, and DBP were found only among children being inactive, implying that irisin may contribute to an improvement in health, especially among children with unhealthy lifestyles.

α2-HS Glycoprotein in Plasma Extracellular Vesicles Inhibits the Osteogenic Differentiation of Human Mesenchymal Stromal Cells In Vitro.

Extracellular vesicles (Evs) contain diverse functional proteins, mRNAs, miRNAs, and DNA fragments, are secreted by various types of cells, and play important roles in cellular communication. Here, we show for the first time that plasma Evs inhibited the osteogenic differentiation of mesenchymal stromal cells (MSCs) in vitro and the level of inhibition was positively correlated with the plasma Evs concentration. Plasma Evs downregulated the expression of markers such as osteocalcin (OCN), Runt-related transcription factor 2 (Runx2), and Osterix at mRNA levels required for osteogenic differentiation and reduced pSmad1/5/8 levels in MSCs. Furthermore, pSmad1/5/8 levels increased and MSCs underwent normal osteogenic differentiation after Evs-derived α2-HS glycoprotein (AHSG) function was inhibited with an anti-AHSG neutralizing antibody. However, the levels of pERK1/2, active ß-catenin, and HES1 were not significantly altered. Therefore, we propose that as essential components of the extracellular microenvironment of MSCs, plasma Evs are taken up by MSCs and subsequently repress osteogenic differentiation through an AHSG-mediated decrease in pSmad1/5/8 levels. Our work identifies plasma Evs as novel regulators of MSC osteogenic differentiation.

Insights on the nitrate reduction and norfloxacin oxidation over a novel nanoscale zero valent iron particle: Reactivity, products, and mechanism.

Herein, the application of a novel acid mine drainage-based nanoscale zero valent iron (AMD-based nZVI) for the remediation of nitrate and norfloxacin (NOR) was studied. Experimental results indicated that the catalytic reactivity of AMD-based nZVI toward nitrate reduction was superior to that of iron salt-based nanoscale zero valent iron (Iron salt-based nZVI). The presence of ultrasound irradiation could significantly enhance the reactivity toward both the nitrate reduction and NOR oxidation processes. The optimal efficiencies of nitrate and NOR by AMD-based nZVI/US process could be kept 96 and 94% within 120 min, respectively. Ammonia was identified as a major product in nitrate reduction process, while three oxidation products were observed in NOR degradation process. Both reduction reaction of nitrate from AMD-based nZVI and oxidation reaction of NOR from US-assisted Fenton system might be involved in AMD-based nZVI/US process. The AMD-based nZVI/US process showed a better performance on the removal of NOR compared with that of nitrate. The findings of the present work could be as a guide and show that AMD-based nZVI/US process is feasible for the remediation of both nitrate and NOR in real wastewater.

Goethite catalyzed Cr(VI) reduction by tartaric acid via surface adsorption.

The surface catalysis of goethite on the Cr(VI) reduction by tartaric acid was examined together with its adsorption characteristics towards the two reactants. The results showed the adsorption of tartaric acid by goethite was favorable at low pH and adsorption isotherm could be properly described by Langmuir model. The adsorption kinetic curves for both reactants obeyed the pseudo second-order rate model (R2 >0.99). The FTIR spectrum suggested the formation of bidentate binuclear surface complexes between tartaric acid and goethite. At pH 4.50, the reduction percentage of 0.1 mM Cr(VI) by 1.0 mM tartaric acid alone was about 12% after 72 h, while which was increased to 100% in the presence of goethite within 24 h. Kinetic results revealed the Cr(VI) reduction only occurred between the adsorbed tartaric acid and the aqueous Cr(VI) since the Cr(VI) adsorption was completely inhibited under the examined conditions. Meanwhile, the catalysis of aqueous Fe(III) released from the goethite surfaces was excluded due to its low concentration (<5 µM). With the initial concentration of tartaric acid decreased to 0.1 mM, Cr(VI) reduction could be completed within 4 h, confirmed by the XPS result that only Cr(III) species existed on the goethite surfaces. In this case, electron transfer was suggested to occur directly between the two adsorbed reactants or goethite was believed to serve as an ideal channel to allow electron excited from the adsorbed tartaric acid to transfer to the adsorbed Cr(VI). The findings above were helpful for us to understand the Cr(VI) reduction by organic compounds in soils with rich contents of Fe-oxides.

Photocatalytic removal of phenanthrene and algae by a novel Ca-Ag3PO4 composite under visible light: Reactivity and coexisting effect.

In this study, the feasibility of a novel Ca-Ag3PO4 composite with visible light irradiation for the phenanthrene (PHE) degradation and algae inactivation in artificial seawater was firstly investigated. The experimental findings revealed that Ag3PO4 phase was sucessfully formed on the Ca-based material, and the presence of Ca-based material could effectively keep Ag3PO4 particles stable. An excellent performance on PHE degradation or algae inactivation was observed from Ca-Ag3PO4 composite under visible light irradiation. The degradation of PHE or inactivation of algae not only could be efficiently achieved in the single mode, but also could be successfully achieved in the coexisting mode. Above 96% of PHE and algae were simultaneously removed within 12 h in the Ca-Ag3PO4/visible light system. It was further observed that the degradation of PHE and/or inactivation of algae increased with the increase of Ca-Ag3PO4 dosage. HO was the primary radical responsible for PHE degradation, whereas HO and Ag+ released from Ca-Ag3PO4 mainly contributed to the algae inactivation. A possible mechanism involving the catalytic removal of PHE and algae by Ca-Ag3PO4 under visible light irradiation was proposed. This study provides helpful guide for the simultaneous removal of various pollutants in real seawater.

Changes in atrazine speciation and the degradation pathway in red soil during the vermiremediation process.

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) is a triazine herbicide intensively used in agricultural production and is often detected in different environmental matrices at concentrations above the permitted limit. This study investigated the influence of two earthworm species (epigeic Eisenia foetida and endogeic Amynthas robustus) on atrazine speciation and the degradation pathway. Our results revealed that both earthworms significantly accelerated atrazine degradation in a 28-day vermiremediation, and the residual atrazine declined from 4.23 ±â€¯0.21 mg/kg in bulk soils to 0.51 ±â€¯0.29 mg/kg (E. foetida) and 0.43 ±â€¯0.19 mg/kg (A. robustus). By consuming organic matter (from 40.37 ±â€¯1.14 to 36.31 ±â€¯1.55 and 34.59 ±â€¯1.13 g/kg for E. foetida and A. robustus) and neutralizing the soil pH (from 5.37 ±â€¯0.27 to 6.36 ±â€¯0.11 and 6.61 ±â€¯0.30 for E. foetida and A. robustus), both earthworms reduced humus-fixed atrazine and increased the available atrazine. The percentage of available atrazine increased from 8.80 ±â€¯0.21% in bulk soil to 10.30 ±â€¯0.29% and 16.42 ±â€¯0.18% in the vermiremediation treatments. Both earthworms promoted the hydroxyatrazine pathway by consuming soil organic matter and encouraged the deethylatrazine/deisopropylatrazine pathway by neutralizing the soil pH. Our findings unravel a new mechanism of vermiremediation by improving the soil physical-chemical properties and altering the atrazine degradation pathway, providing new insights into the influential factors on atrazine bioremediation in red soil.