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Using ethylene glycol as solvent and PVP as structure-directing agent, CuFe2O4 nanospheres were successfully prepared by solvothermal method. The crystal structure, morphology, magnetic properties, and pore-size distribution of samples were characterized by using X-ray diffraction, scanning electron microscope, transmission electron microscope, VSM, and BET, respectively. The effects of various preparation factors on the crystal form and morphology of the obtained samples were systematically discussed. The result exhibited that the self-assembled hollow nanospheres with good crystal form and morphology are obtained under the conditions of 0.50 g PVP, 9 mmol NaAc, reaction temperature of 180 °C, and reaction time of 24 h. The catalytic activity of CuFe2O4 hollow nanospheres was evaluated by the degradation of methylene blue (MB) and the possible degradation mechanism and pathway of MB in the CuFe2O4/H2O2 photo-Fenton-like system were proposed. In addition, the properties of CuFe2O4 particles prepared by different methods were compared and analyzed. The sample synthesized by solvothermal method has a large specific surface area and excellent magnetic properties. Furthermore, the increase in the photoelectric response and the conductivity are beneficial to the improvement of catalytic performance. [ABSTRACT FROM AUTHOR]

• Palygorskite-based HZSM-5 zeolite was prepared by hydrothermal method. • Zn-UIO-66/(HZSM-5)-palygorskite catalyst showed excellent catalytic performance. • The CO 2 adsorption performance over the Zn-UIO-66 system was simulated by DFT. • Hydrogenation of CO 2 to aromatics follows the methanol-mediated pathway. Palygorskite-based HZSM-5 zeolite was prepared through the hydrothermal method using acidified palygorskite as the Si source and supporter. A series tandem composite of M (Zn, Ga, In)-UIO-66/(HZSM-5)-palygorskite was obtained using metal–organic frameworks (UIO-66) as the carrier using the physical mixing method. XRD, SEM, TEM, N 2 adsorption–desorption, NH 3 -TPD, Py-IR, H 2 -TPR, XPS, and CO 2 -TPD were used to investigate the composite's physical and chemical properties. The calcination temperature effect of palygorskite-based HZSM-5 zeolite, Zn to Zr mole ratio, the space distance between Zn-UIO-66 and palygorskite-based HZSM-5 zeolite, and reaction conditions on the catalytic performance of CO 2 hydrogenation to aromatics were investigated. Zn-UIO-66/(HZSM-5)-palygorskite showed excellent catalytic performance. CO 2 conversion was 21.2% and selectivity for benzene, toluene, and xylene (BTX) were 84.9% under optimal reaction conditions. In situ DRIFTS and Density Functional Theory (DFT) were used to investigate and simulate the CO 2 adsorption performance over the Zn-UIO-66 system. In addition, the reaction mechanism of CO 2 hydrogenation was explored. The transition state and energy barrier for CO 2 hydrogenation to aromatics were obtained by minimum energy search of the LST/QST transition state. [ABSTRACT FROM AUTHOR]

ABSTRACT Foxl2 and FTZ-F1 play a crucial role in the regulation of gonad development in fish and mammals, but studies of their function in amphibians are scarce. We isolated the full length of Foxl2 ( adFoxl2) and Ftz-F1 ( adFtz-f1) cDNA from the Chinese giant salamander Andrias davidianus and quantified its expression in various tissues and developing gonads. The adFoxl2 gene encodes 301aa including a conserved forkhead box, and the adFtz-f1 gene encodes 467aa containing an Ftz-F1 box. The amino acid sequences showed high homology with other amphibians. adFoxl2 expression was high in ovary, whereas adFtz-f1 was higher in testis, moderate in pituitary, ovary, and kidney; and low in the remaining tested tissues. Expression of adFoxl2 gradually increased from 1Y to 5Y in ovary, whereas adFtz-f1 expression gradually decreased in testis. In addition, adFoxl2 and adFtz-f1 were detected in granulosa cell in ovary and in spermatocytes in testis. The adFoxl2 transcription was inhibited in brain and ovary after treatment with methyltestosterone and with letrozole, whereas adFtz-f1 expression was upregulated. High-temperature suppressed the expression of adFxl2 in ovary and enhanced the transcription of adFtz-f1. These results suggest that adFoxl2 functioned in ovary differentiation, whereas adFtz-f1 played a role in testis development, which lays a foundation for study of the sex differentiation mechanism in A. davidianus. [ABSTRACT FROM AUTHOR]

We prepared ZnZr 7 O/HZ-1.5NH 4 F tandem catalyst with high catalytic activity for the direct conversion of CO 2 hydrogenation to aromatics by combining theoretical calculations and experiments. [Display omitted] • It was simulated that the (0 1 0) plane of the sheet HZSM-5 had the strongest adsorption capacity for CH 3 O* and CHOO*. • We prepared catalysts with high catalytic activity and stability by combining theoretical calculations and experiments. • The thickness can be precisely adjusted to prepare a series of sheet HZSM-5 by adding urea and NH 4 F. • Urea inhibits the generation of defective sites in HZSM-5, while NH 4 F promotes the generation of defective sites. • The thickness of the sheet HZSM-5 is also a factor affecting the catalytic activity. The adsorption properties of CH 3 O* and CHOO* adsorbed on the three crystal planes (0 0 1, 0 1 0, 1 0 1) of HZSM-5 were simulated by the generalized gradient approximation (GGA) of density functional theory (DFT), it was found that the (0 1 0) plane corresponding to the b-axis of the sheet HZSM-5 had the strongest adsorption energy for CH 3 O* and CHOO*. Therefore, we successfully synthesized sheet HZSM-5 with different thicknesses by adding the inhibitor (urea) and mineralizer (F−) to the synthesis system based on the theoretical calculations. The physicochemical properties of HZSM-5 were investigated by the characterization methods of SEM, TEM, Py-IR, OH-IR, CO 2 -TPD and so on. The results showed the thickness of HZSM-5 can be precisely adjusted by adding urea and NH 4 F and changing the ratio of urea/NH 4 F or TPAOH/NH 4 F. Then, the sheet HZSM-5 and ZnZr 7 O were connected in tandem to investigate the reaction conditions and catalytic performance for the direct conversion of CO 2 hydrogenation to aromatics. It was found that the HZ-1.5NH 4 F had a large specific surface area, suitable B acid content and more defect sites. These advantages resulted in a high aromatic selectivity of 77.5% and CO 2 conversion of 17.6% over ZnZr 7 O/HZ-1.5NH 4 F. Meanwhile, it exhibits stable performance and no significant deactivation after 80 h of operation. [ABSTRACT FROM AUTHOR]

This paper presents an E -derivation analogue of a result on derivations due to van den Essen, Wright and Zhao. We prove that the image of a locally finite K - E -derivation of polynomial algebras in two variables over a field K of characteristic zero is a Mathieu subspace. This result together with that of van den Essen, Wright and Zhao confirms the LFED conjecture in the case of polynomial algebras in two variables. [ABSTRACT FROM AUTHOR]

• The H-ZSM-5 with different morphologies were rationally designed and the synthesis mechanism was illustrated. • Physical mixture of H-ZSM-5 and In 2 O 3 , Cu-Zn-Al and ZnZrO were used to CO 2 hydrogenation to aromatics. • The fewer intermediates were observed on the Cu/ZnO/Al 2 O 3 -sheetZ5 and In 2 O 3 -sheetZ5 in In-situ DRIFTS spectra. • The ZnZr 7 O(5 0 0)-sheet-Z5 showed the best catalytic performance of BTX, the high selectivity of p-xylene was achieved over the ZnZr 7 O(5 0 0)-chainZ5. • Enhanced CO 2 conversion by ZnZr 7 O(5 0 0)-sheet-Z5 catalysts at suitable calcination temperature and oxygen vacancy concentration. The efficient that to concert CO 2 into high value-added chemicals is a promising and potential strategy to reduce the consumption of petroleum resources, especially as an alternative route to MTA, where direct conversion of aromatics can be achieved through CO 2 hydrogenation. Herein, a series of metal oxides (In 2 O 3 , Cu-Zn-Al and ZnZr x O with different Zr/Zn and calcined at different temperatures) and different morphologies of spherical, hollow, sheet, and chain HZSM-5 were rationally designed, and then connected with metal oxides and HZSM-5 in tandem to investigate the reaction conditions and catalytic performance for the direct conversion that from CO 2 hydrogenation to aromatics, the reaction mechanism was investigated using In-situ DRIFTS. Furthermore, due to the synergy between the respective excellent properties of HZSM-5 zeolites and metal oxides, the selectivity of aromatic up to 75.7% and conversion of CO 2 was 14.5% over ZnZr 7 O(5 0 0)-sheet HZSM-5 tandem catalyst, while achieving high selectivity of 64.1% for BTX. Moreover, high selectivity of the target product to xylene was achieved over the ZnZr 7 O(5 0 0)-chain HZSM-5 tandem catalyst due to the fact that the molecular kinetic radius of p-xylene was close to the b-axis pore radius of HZSM-5, and an appropriate increase in the b-axis length was beneficial to improve the selectivity of p-xylene, which opened up a broad path for the design of catalysts for CO 2 hydrogenation to aromatics. [ABSTRACT FROM AUTHOR]

The BiOBr/FeMoO 4 composite enriched with oxygen vacancies promotes the activation of peroxydisulphate (PDS) and the degradation of oxytetracycline hydrochloride (OTC). [Display omitted] • Crystal plane regulation induces significant changes in oxygen vacancy concentration and electronic structure. • The non-pathway dominated FBOV10/PDS/Light system efficiently degrade organic pollutants in saline water. • The mechanism and toxicity assessment of FBOV10 was proposed based on experimental and DFT calculations. The investigation about the mechanism of crystal plane regulation on the generation of oxygen vacancies remains a challenge. In this paper, BiOBr/FeMoO 4 composites were synthesized by precise control of crystal plane growth, and it exhibited the enhanced concentration of oxygen vacancies due to lower formation energy of oxygen vacancies. The composite performs higher photo-Fenton-like ability for degrading oxytetracycline hydrochloride (OTC). Structural analyses and theoretical calculations reveal that crystal plane regulation induces significant changes in oxygen vacancy concentration. The BiOBr/FeMoO 4 /peroxydisulphate (PDS) /light system, which dominated by the non-radical pathway, degraded 96.8 % ± 1.0 % of OTC within 30 min. The activation mechanism of the system and the degradation pathway of OTC were elucidated. The intermediates in the degradation process of OTC were evaluated using liquid chromatograph-mass spectrometer (LC-MS), toxicity evaluation software tool (T.E.S.T) and soybean germination experiments. This work offers novel insights into the pivotal role of crystal plane directional regulation in the quantitative generation of oxygen vacancies. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of this research was to characterize the structure, expression, and function of unc-13d in the process of sex reversal in Monopterus albus. The expression profile of unc-13d suggested that unc-13d plays an important role in sex reversal. Additionally, the DNA methylation of the promoter of unc-13d exhibited negative correlation with gene expression, especially at site 114. Furthermore, we found that dmrt1 antagonistically regulates foxl2 expression through unc-13d. Monopterus albus is a protogynous hermaphroditic fish that changes from female to male, but the underlying sex change mechanism remains as-yet unknown. In this study, we firstly cloned and characterized the sequence and protein structure of unc-13d of M. albus. We found that the genomic structure of unc-13d was different from other species. Expression was detected in the developing gonad by applying qRT-PCR and in situ hybridization. We found that the expression of unc-13d in the ovotestis was higher than in the ovary and testes. A strong signal of unc-13d was detected in oocytes and granulosa cells in the ovary and spermatogonia and primary spermatocytes in the testes. We found that the promoter methylation of unc-13d was negatively correlated with gene expression in developing gonads, especially at site 114. A dual-luciferase assay was designed and revealed that dmrt1 regulates promoter activity opposite to foxl2. In summary, during sex reversal, DNA methylation affects the binding of the transcription factor dmrt1 and foxl2 in the promoter region through methylation and demethylation interactions to regulate the expression of unc-13d during gonadal development. [ABSTRACT FROM AUTHOR]

The 1% Zn Z8 (SAC)/Z5 catalyst prepared by steam-assisted crystallization method with ZIF-8 as sacrificial template and Zn source shows high BTX selectivity (69.8%) and excellent stability in MTA reaction. [Display omitted] • The Zn modified HZSM-5 zeolite was prepared by using ZIF-8 as sacrificial template and Zn source. • The steam-assisted crystallization method is the key to the preparation of high crystallinity nano-hierarchical pore structure Zn/Z5 catalyst. • The grain size, physical properties and acidity distribution of Zn/Z5 can be adjusted by controlling the addition amount of ZIF-8. • Appropriate acid distribution, smaller particle size, larger specific surface area and abundant mesoporous structure are the keys to obtaining higher BTX selectivity and excellent stability. Methanol to aromatics (MTA) is an effective way to produce aromatics by non-petroleum route. The acidity and structure of zeolite catalysts are the key to aromatics yield and stability of catalysts in MTA reaction. Here, Zn-modified HZSM-5 catalysts were prepared by physical mixing method (PM), in-situ hydrothermal synthesis method (SH) and steam-assisted crystallization method (SAC) using ZIF-8 as sacrificial template and Zn source. XRD, SEM, TEM, N 2 adsorption-desorption, ICP-OES, NH 3 -TPD, Py-IR, XPS, H 2 -TPR, TG characterization methods were used to investigate the physical and chemical properties of the catalysts. The influence of preparation methods of catalysts, the addition amount of ZIF-8, different Zn sources and reaction conditions on the products distribution in MTA reaction were investigated. The results showed that the crystallinity of Zn Z8 (SAC)/Z5 catalyst was improved and the hierarchical pore structure was obtained successfully after introduced ZIF-8 by steam-assisted crystallization method. Among them, Zn Z8 mainly exists as ZnOH+ species, which improved the utilization rate of Zn atoms and more L acid sites and moderate acid concentration were formed. The addition amount of ZIF-8 can affect the crystalline size, pore structure and the concentration of ZnOH+ species of Zn Z8 (SAC)/Z5. An appropriate ratio of B/L acid concentration was formed when adding an appropriate amount of ZIF-8. Compared with the traditional Z5 catalyst modified with Zn(NO 3) 2 as Zn source (1% Zn ZN (SAC)/Z5), there are smaller particle size, larger specific surface area and mesopore volume as well as suitable acid distribution in 1% Zn Z8 (SAC)/Z5 catalyst. The preparation method of catalyst, the addition amount of ZIF-8, different Zn sources and reaction conditions have a significant effect on the selectivity of BTX. [ABSTRACT FROM AUTHOR]

The dead end gene has been identified as a essential factor for Primordial germ cells (PGCs) migration and survival in many species, but its role in Monopterus albus is unclear. In order to clarify the function of dead end gene in M.albus PGCs migration and survival, we first characterized the expression profile of M.albus dead end (Madnd) in developing embryos and various tissues. qRT-PCR revealed that Madnd transcripts were exclusively detected in gonad, including ovary, testis and ovotestis.Embryos injected with a Madnd morpholino (Madnd-MO) exhibited down-regulation of the vasa gene. Furthermore, the GFP signal show the PGCs migration in control group were injected with GFP-nanos3 3′-UTR mRNA for visualization, as described in a previous study, yet it was disappeared after embryos injected with Madnd-MO.Finally, we characterized the genomics sequence of the Madnd gene and designed five gRNAs for genome editing. Three gRNAs were selected for microinjection according to the results of in vitro tests. gRNAd1 was used for microinjection with the Cas9 protein and was confirmed to be effective. Our analysis in this study suggested that Madnd play a key role in PGCs migration and survival in M. albus. These data provide the basis for the production of fast-growing and reproductively M.albus sterile. • Expression profile of Madnd gene in developing embryos and tissues was reported. • Madnd was crucial for PGCs migration and survival in embryos. • Genome editing technology was developed for the further studies in the future. [ABSTRACT FROM AUTHOR]

Palygorskite was used as a silicon and partial aluminum source to prepare SAPO-34 molecular sieves using diethylamine, triethylamine, morpholine and tetraethylammonium hydroxide as templates. The synthesized SAPO-34 molecular sieves were characterized by using the methods of XRD, SEM, EDS, BET, FT-IR, NH 3 -TPD, H 2 -TPR and TG. Composite catalysts of CuO-ZnO-Al 2 O 3 /SAPO-34 were prepared by mechanically mixing SAPO-34 molecular sieves with CuO-ZnO-Al 2 O 3 and were used in the direct synthesis of light olefins via CO 2 hydrogenation. The results showed that SAPO-34 molecular sieves prepared by acid-treated palygorskite using tetraethylammonium hydroxide as a template had a higher specific surface area, a greater CO 2 conversion rate and higher light olefin selectivity. The CO 2 conversion rate reached 53.5%, the light olefin selectivity reached 62.1%, and the yield reached 33.2% when the reaction conditions were as follows: reaction temperature 673 K, reaction pressure 3.0 MPa, volume ratio of CO 2 /H 2 1:3 and 0.5 g composite catalyst. • SAPO-34 molecular sieves were synthesized using palygorskite as raw material. • CuO-ZnO-Al2O3/SAPO-34 catalyst was used in CO2 to light olefins reaction. • The prepared SAPO-34 molecular sieves exhibited excellent selectivity of light olefins. [ABSTRACT FROM AUTHOR]

To search the evidence of molecular evolution mechanism for aquatic and cave habitat in Andrias davidianus, the evolution analysis was carried out among several species transcriptome data. The transcriptome data of Notophthalmus viridescens, Xenopus tropicalis, Cynops pyrrhogaster, Hynobius chinensis and A. davidianus were obtained from the Genbank and reassembled except Xenopus tropicalis. The BLAST search of transcriptome data obtained 1244 single-copy orthologous genes among five species. A phylogenetic tree showed A. davidianus to have the closest relationship to H. chinensis. Fourteen positively selected genes were detected in A. davidianus and N. vridescens group and fifteen in A. davidianus and H. chinensis group. Five genes were shared in the both groups which involved in the immune system, suggesting that A. davidianus adaptation to an aquatic and cave environment required rapid evolution of the immune system compared to N. viridescens and H. chinensis. [ABSTRACT FROM AUTHOR]

Background: Monopterusalbus is a hermaphroditic fish with sex reversal from ovaries to testes via the ovotestes in the process of gonadal development, but the molecular mechanism of the sex reversal was unknown. Methods: We produced transcriptomes containing mRNAs and lncRNAs in the crucial stages of the gonad, including the ovary, ovotestis and testis. The expression of the crucial lncRNAs and their target genes was detected using qRT‒PCR and in situ hybridization. The methylation level and activity of the lncRNA promoter were analysed by applying bisulfite sequencing PCR and dual-luciferase reporter assays, respectively. Results: This effort revealed that gonadal development was a dynamic expression change. Regulatory networks of lncRNAs and their target genes were constructed through integrated analysis of lncRNA and mRNA data. The expression and DNA methylation of the lncRNAs MSTRG.38036 and MSTRG.12998 and their target genes Psmβ8 and Ptk2β were detected in developing gonads and sex reversal gonads. The results showed that lncRNAs and their target genes exhibited consistent expression profiles and that the DNA methylation levels were negatively regulated lncRNA expression. Furthermore, we found that Ptk2β probably regulates cyp19a1 expression via the Ptk2β/EGFR/STAT3 pathway to reprogram sex differentiation. Conclusions: This study provides novel insight from lncRNA to explore the potential molecular mechanism by which DNA methylation regulates lncRNA expression to facilitate target gene transcription to reprogram sex differentiation in M.albus, which will also enrich the sex differentiation mechanism of teleosts. Highlights: Construction of the lncRNA-mRNA interaction network in the sex differentiation. DNA methylation was negatively associated with lncRNA expression in developing gonads. Ptk2β regulate Ptk2β/EGFR/STAT3 pathway to potentially regulate sex differentiation. Plain language summary: Monopterusalbus is a hermaphroditic fish that undergoes sex reversal from female to male via intersex during the process of the gonadal differentiation which was an ideal model for epigenetic modification research. After laying eggs, the female M.albus reversal to the intersex. So that the female have a shorter stage and smaller body size which cause low egg production. In the present study, we produced the transcriptomes which contain mRNA and lncRNA in the crucial stage of the gonad including ovary, ovotestis and testis. This effort reveals that gonadal development was a dynamic expression changes. Regulatory networks of lncRNAs and its target genes were constructed though integrated analysis of lncRNA and mRNA data. We found DNA methylation was negatively associated with lncRNA (MSTRG.38036 and MSTRG.12998) expression in developing gonads. Additionally, 17α-methyltestosterone inhibit the expression of lncRNA and increase methylation. Furthermore, we found that Ptk2β probably regulates cyp19a1 expression via the Ptk2β/EGFR/STAT3 pathway to reprogram sex differentiation. The present study on the gonadal differentiation of M.albus provides novel insights from lncRNA to explore potential molecular mechanism. In the future, function of the lncRNA will be further studied and the gene editing technology will be applied to cultivate the female with high fecundity to improve the yield of fish fry. [ABSTRACT FROM AUTHOR]

• Integrating crop phenology and machine learning improves yield prediction. • Ground and remotely sensed phenology data are compared for yield prediction. • Yield predictions can be made at the second phenological stage. • Spatially, most counties display prediction errors below 10 %. • Vegetation index, ET and elevation are key factors for predicting corn yield. Precise and timely crop yield predictions at large scales are crucial for safeguarding global food security. A key factor in accurate yield forecasting is the integration of multi-source environmental data, where the choice of time windows for aggregating these variables plays a pivotal role. Segmenting time windows by phenological stages allows for more precise extraction of environmental variables, capturing the complex interactions between crop development and external factors. However, the effectiveness of this approach in improving yield prediction accuracy, especially when comparing ground-based and remote sensing-derived land surface phenology data, remains largely unexplored. In this study, we investigate how phenology-based time windows affect corn yield predictions, using machine learning algorithms and multi-source environmental data from the U.S. Corn Belt. We systematically analyzed and compared models incorporating either ground-based or land surface phenology. By segmenting the growing season into six crucial stages (BBCH 00-99) and formulating specific yield forecasting models for each stage, we determined the optimal lead times for predictions utilizing both sources of phenological data. Our findings suggested that the incorporation of phenology-derived crop growth windows significantly enhances the accuracy of yield prediction by approximately 10 % compared to the fixed-season method. Ground-based phenology data from the USDA crop progress report slightly outperformed MODIS-based land surface phenology data, achieved the highest accuracy with the XGBoost model (R2 = 0.668, RMSE = 1.09 t/ha, MAE = 0.84 t/ha). Furthermore, this study demonstrated that reliable corn yield predictions could be made as early as the second phenological stage (Emerged-Silking for ground phenology, MidGreenup-Maturity for MODIS phenology). In regions where ground observations are limited or unavailable, land surface phenology emerges as a promising alternative. This study presents a robust framework for precise and extensive crop yield modeling and early prediction, which is crucial for making informed agricultural decisions and ensuring food security. [ABSTRACT FROM AUTHOR]

In Fenton-like systems, a slow-release of hydrogen peroxide (H 2 O 2) is of great value in improving the sustainable treatment of pollutants. In this study, calcium peroxide (CaO 2) was first synthesized by different methods, and its slow-release performance of H 2 O 2 was evaluated. Then CaO 2 @PDA composites (referred to as CP-X, X represent the mass ratio of Polydopamine (PDA) to CaO 2 were prepared by using a simple precipitation method. And the H 2 O 2 slow-release experimental result indicates that the average release rate of the prepared CP-1.0 is 0.19 mmol g−1·min−1 within 130 min. The release of H 2 O 2 from CP-1.0 is consistent with the biexponential biphasic kinetic model, where water molecules and H 2 O 2 osmotic diffusion are the main factors affecting the rate of H 2 O 2 release. Decolourisation removal of crystalline violet (CV) solution was carried out using CP-1.0 as oxidants. Under the conditions of 0.02 g CP-1.0, pH = 6.5, and 20 °C, more than 98.0% of CV solution (30 mg/L) was removaled within 30 min. Then, possible degradation pathways were postulated using a combination of density functional theory (DFT) and liquid chromatography mass spectrometry (LC-MS). Finally, the decolourisation degradation mechanism was proposed according to the active species quenching experiments and Electron Paramagnetic Resonance (EPR) analysis. This study presents novel insights into the removal of emerging pollutants in aqueous media by CaO 2 -based Fenton-like systems. [Display omitted] • The slow release of H 2 O 2 through pda-coated CaO 2 improves the sustained and efficient degradation of pollutants. • The average release rate of CP-1.0 was 0.19 mmol g−1·min−1 within 130 min. • 0.02 g of CP-1.0 effectively degraded 98.0% of CV solution (30 mg/L) within 30 min at pH = 6.5, 20 °C. • The reactive active sites of CV molecules were predicted by DFT calculations. • This study provides new insights into the degradation of pollutants by cao2-based Fenton-like systems. [ABSTRACT FROM AUTHOR]

Due to the benefits of artificial peroxidase-like enzymes, Flower-like Mn 3 O 4 -FeS 2 /Fe 2 O 3 composites with multiple active sites prepared by a one-step solvothermal method.The synergistic cyclic reaction between Mn and Fe on the catalyst surface enhances the generation of active radicals, which together promote the efficient degradation of BPA. In the presence of hydrogen peroxide (H 2 O 2), Mn 3 O 4 -FeS 2 /Fe 2 O 3 could generate hydroxyl radicals (·OH) and superoxide radicals (·O 2 -) in buffer solution of pH=4.5 and catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxidation products (ox TMB). The steady-state kinetic constants (K m) of TMB and H 2 O 2 were obtained by Michaelis-Menten and Lineweaver-Burk models, which are 1.34 mM and 1.00 mM, respectively. This reveals the nice catalytic efficiency of Mn 3 O 4 -FeS 2 /Fe 2 O 3 as enzyme mimics. Under the condition of 10 mg Mn 3 O 4 -FeS 2 /Fe 2 O 3 catalyst, 100 μL H 2 O 2 and pH = 4.5, the degradation efficiency of Bisphenol A (BPA) reaches 100 % when treating 40 mL of 50 mg L−1 BPA for 30 min at room temperature. Moreover, after 5 cycles of degradation, the BPA degradation efficiency of 85.8 % was still maintained. Therefore, the as-prepared Mn 3 O 4 -FeS 2 /Fe 2 O 3 sample could potentially be applied in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Peroxidation of methyl ethyl ketone catalyzed by UiO-66 and the thermal stability analysis. [Display omitted] • The synthesised MEKP possessed 10.81 % reactive oxygen content and 70.2 % yield. • UiO-66 synthetic MEKP has good catalytic properties, stability and renewability. • This study provides a new multiphase catalytic pathway for the synthesis of peroxides. The synthesis of methyl ethyl ketone peroxide (MEKP) generally belongs to the homogeneous strong acid catalysed process. Acid is corrosive to the equipment, cannot be reused and thus has a large amount of wastewater to be post-treated and needs high treatment cost. The heterogeneous catalytic synthesis of organic peroxides is gaining more and more attention. In this study, methyl ethyl ketone peroxide was prepared from butanone oxidized by hydrogen peroxide and in the presence of UiO-66 as the catalyst. Under the conditions that the molar ratio of H 2 O 2 to methyl ethyl ketone (MEK) is 2, the mass ratio of UiO-66 to MEK is 0.045, the reaction temperature is 30 °C, and the reaction time is 70 min, the active oxygen content of the product reaches 10.81 %, and the main products are methyl ethyl ketone peroxide and its oligomers. The thermal decomposition heat and activated energy are 748 J·g−1 and 101 kJ·mol−1 based on the thermogravimetric-differential scanning calorimetry (TG-DSC) determination. Finally, after four cycles, uio-66 still had 70.2 % yield, and XRD and FTIR after the cycles proved the good stability of the catalyst. The study provides a new way for the production of methyl ethyl ketone peroxide by heterogeneous catalytic oxidation. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeMoO 4-x N x was designed and used in a photo-Fenton-like system. • FeMoO 4-x N x /H 2 O 2 /light system showed excellent degradation performance for TC. • The toxicity of intermediates was analyzed. • The mechanism of FeMoO 4-x N x was proposed based on experimental and DFT calculations. Tetracycline antibiotics are widely used in agriculture and medicine, and irregularities in their application and subsequent treatment can easily lead to antibiotic residues. Consequently, for efficient degradation of tetracycline (TC) from high saline water, FeMoO 4-x N x photo-Fenton-like catalysts were synthesized in this study using potassium cyanate (KOCN) as the nitrogen source. The photo-Fenton-like performance of FeMoO 4-x N x was significantly enhanced by incorporating different amounts of KOCN to regulate the nitrogen content and morphology of FeMoO 4-x N x. The density functional theory calculations demonstrate that the adsorption energy of dissolved oxygen on the surface of FeMoO 2 N 2 is significantly enhanced by the presence of Mo. Based on the LC-MS results, a putative pathway for TC degradation by FeMoO 2 N 2 was proposed, and the degradation intermediates were assessed through toxicological evaluation and soybean germination experiments. A possible mechanism for the efficient degradation of TC in saline water using FeMoO 4-x N x microsphere catalysts was proposed. [ABSTRACT FROM AUTHOR]

Background: Monopterus albus is a hermaphroditic and economically farmed fish that undergoes sex reversal from ovary to testis via ovotestis during gonadal development. The epigenetic changes that are associated with gonadal development in this species remain unclear. Methods: We produced DNA methylome, transcriptome, and chromatin accessibility maps of the key stages of gonad development: ovary, ovotestis, and testis. The expression of the key candidate genes was detected using qRT-PCR and in situ hybridization and the methylation levels were analysed using bisulphite sequencing PCR. Promoter activity and regulation were assessed using dual-luciferase reporter assays. Results: Gonadal development exhibits highly dynamic transcriptomic, DNA methylation, and chromatin accessibility changes. We found that DNA methylation status, especially of the transcription start site, was significantly negatively correlated with gene expression while chromatin accessibility exhibited no correlation with gene expression during gonadal development. The epigenetic signatures revealed many novel regulatory elements and genes involved in sex reversal, which were validated. DNA methylation detection and site mutation of plastin-2 promoter, as a candidate gene, revealed that DNA methylation could impact the binding of transcription factor dmrt1 and foxl2 through methylation and demethylation to regulate plastin-2 expression during gonadal development. Conclusions: These data provide novel insights into epigenetic modification and help elucidate the potential molecular mechanism by which dynamic modification of DNA methylation plays a crucial role in gonadal development. Highlights: DNA methylation modification plays a more crucial role than chromatin accessibility in gonad development. DNA methylation in the transcription start site plays a key role in gonad development. DNA methylation of the plastin-2 promoter inhibited gene expression. Plastin-2 is positively regulated by dmrt1 while negatively regulated by foxl2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-catalytic effect of 1 T-MoS 2 greatly enhances the efficiency of photo-Fenton degradation. • The degradation efficiency of MB and RhB both reached 99.8% in 18 min. • The ·OH and visible light have synergistic in the photo-Fenton degradation system. • Density functional theory (DFT) was used to simulate the adsorption energy of H 2 O 2. Right here, flower-like FeMoO 4 @1T-MoS 2 composites were prepared by modifying FeMoO 4 microspheres with two-dimensional lamellar 1T-MoS 2 as co-catalyst, which was used for photo-Fenton catalysis degradation of binary dyes mixed with methylene blue (MB) and rhodamine B (RhB). Then various parameters affecting the generation of ·OH in the system were investigated. Systematic research shows that the degradation efficiency of MB and RhB can reach 99.8% in 18 min when the Mo/Fe molar ratio of the composite is 1:1. Furthermore, these experiments data were fitted by pseudo-first order kinetics model and pseudo-second order kinetics model. Subsequently the density functional theory (DFT) simulation results showed that FeMoO 4 exhibited excellent adsorption for H 2 O 2 , and the introduction of 1T-MoS 2 played a certain role in the adsorption and activation of H 2 O 2. Finally, the degradation pathways of MB and RhB were proposed to determine intermediates during photo-Fenton process by LC-MS and the reaction mechanism was detailed investigated by quenching experiment of active free radicals. FeMoO 4 @1T-MoS 2 has also excellent stability and highlights the potential and prospect of the composite for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • P-doped graphite carbon nitride can effectively promote charge separation. • TC degradation efficiency is more than 90% in both acidic and neutral conditions. • PCNFV-400 showed high degradation activity for other antibiotics. • PCNFV-400 has good performance in practical applications. An eco-friendly, economical, and stable heterojunction composite phosphorus-doped graphite carbon nitride (P-g-C 3 N 4)/FeVO 4 -X was synthesized by one-pot impregnation precipitation, and its physical and photoelectric properties were characterized, P-g-C 3 N 4 /FeVO 4 -400 demonstrated the best performance. The synergistic effect of P-g-C 3 N 4 and FeVO 4 promotes the prolongation of the photogenerated carrier lifetime while improving the electron-hole separation efficiency. The optimal reaction conditions were obtained by varying initial pH, hydrogen peroxide concentration, catalyst dosage, and tetracycline concentration. Meanwhile, tetracycline degradation was also investigated in complex systems with different anions and cations. The generation of hydrogen peroxide in the reaction process was determined by investigating the changes in hydrogen peroxide content, and its generation mechanism was explored. The results of 5 cycles show that the catalyst has good stability. The results of free radical trapping experiments and electron paramagnetic resonance spectroscopy indicate that the main reactive species in the reaction process are superoxide radicals. Therefore, the possible mechanism of tetracycline degradation by P-g-C 3 N 4 /FeVO 4 -400 was proposed alongside an analysis of the degradation pathway. The study provides a promising and effective way to develop high-performance type-II photocatalysts and paves the way for their practical application in wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Background: The Chinese giant salamander Andrias davidianus is an important amphibian species in China because of its increasing economic value, protection status and special evolutionary position from aquatic to terrestrial animal. Its large genome presents challenges to genetic research. Genetic linkage mapping is an important tool for genome assembly and determination of phenotype-related loci. Results: In this study, we constructed a high-density genetic linkage map using ddRAD sequencing technology to obtain SNP genotyping data of members from an full-sib family which sex had been determined. A total of 10,896 markers were grouped and oriented into 30 linkage groups, representing 30 chromosomes of A. davidianus. The genetic length of LGs ranged from 17.61 cM (LG30) to 280.81 cM (LG1), with a mean inter-locus distance ranging from 0.11(LG3) to 0.48 cM (LG26). The total genetic map length was 2643.10 cM with an average inter-locus distance of 0.24 cM. Three sex-related loci and four sex-related markers were found on LG6 and LG23, respectively. Conclusion: We constructed the first High-density genetic linkage map and identified three sex-related loci in the Chinese giant salamander. Current results are expected to be a useful tool for future genomic studies aiming at the marker-assisted breeding of the species. [ABSTRACT FROM AUTHOR]

We characterized the Andrias davidianus T-box 1 (Tbx1) gene. Tbx1 expression was high in testis and low in other examined tissues. Immunohistochemistry detected tbx 1 expression in somatic and germ cells 62 days post-hatching (dph), prior to gonad differentiation. At 210 dph, after gonad differentiation, tbx1 was expressed in spermatogonia and testis somatic cells and in granulosa cells in ovary. Tbx1 expression was up-regulated in ovary after high temperature treatment. In the neomale, tbx 1 expression showed a similar profile to normal males, and vice-versa for genetic male. Over-expression of tbx1 in females after injection of TBX1 protein down-regulated the female-biased genes cyp19a and foxl2 and up-regulated the male-biased amh gene. When tbx 1 was knocked down by tbx 1/siRNA, cyp19a and foxl2 expression was up-regulated, and expression of amh , cyp26a , dmrt1 , and wt1 was down-regulated. Results suggest that tbx1 influenced sex-related gene expression and participates in regulation of A. davidianus testis development. • Characterization and expression profile of Tbx1 in Andrias davidianus • Tbx1 initially expressed in the somatic and germ cells at 62 days post-hatching, prior to gonad differentiation. • Tbx1 expression profiles were changed in the sex reversal individuals • Tbx1 identified by overexpression and knockdown test presented a testicular differentiation gene in Andrias davidianus [ABSTRACT FROM AUTHOR]

• Simultaneous extraction of saponin and polysaccharide from Acanthopanax senticosus fruits with 3c-DES. • Molecular dynamics combined with DFT was used to analysis the mechanism of polysaccharide and saponin extraction. • Box–Behnken design in response surface methodology was used to optimize the factors affecting the extraction yield. As the deep eutectic solvent extraction has the advantages of excellent dissolving capability, high extraction efficiency and selectivity, a three-component deep eutectic solvent (3c-DES) was prepared with betaine , triethanolamine and MgCl 2 · 6H 2 O (betaine : triethanolamine : MgCl 2 · 6H 2 O = 1: 4: 0.08, molar ratio), and was used for simultaneous extraction of Acanthopanax polysaccharide and saponin from Acanthopanax senticosus fruits. Response surface methodology (RSM) was employed to optimize the saponin extraction factors. Under the optimum condition that material-liquid (AS powder to 3c-DES) mass ratio was 1:25 g/g, water content was 29 %, extraction temperature was 49 °C, extraction time was 3.5 h, the yield of saponin and polysaccharide were 1.04 and 3.40 wt%, respectively. The effect order on saponin is temperature > time > material-liquid ratio > water content. A quadratic polynomial parameter mathematical model was established to predict the experimental results. Molecular dynamics combined with density functional theory was used to analysis the mechanism of polysaccharide and saponin extraction that the main driving force is strong hydrogen bonding. The hydrogen bonds among deep eutectic solvent and polysaccharides and saponins is between 3.101 Å and 1.817 Å. The deep eutectic solvent could effectively simultaneously extract the saponins and polysaccharides of Acanthopanax senticosus fruits. [ABSTRACT FROM AUTHOR]

The buckling propagation in deep-sea service sandwich pipes is prone to occur under the influence of third-party loads. Therefore, it is crucial to determine the carrying capacity of the sandwich pipes under combined loading conditions for safety. Currently, the predominant method for studying the carrying capacity of sandwich pipes relies on hyperbaric chamber tests, which fail to reflect adequately the buckling behavior under lateral loads. In this study, the finite element package ABAQUS was used to establish a finite element model that accounted for the lateral load on submarine sandwich pipes. It was solved for the maximum lateral load and compared the results with experimental tests, and then validated the accuracy of our numerical simulation method. This investigation focused on studying the buckling behavior of sandwich pipes under displacement control, and analyzed the relationship between buckling behavior and external pressure as well as lateral load. Furthermore, the comprehensive parametric studies were performed to analyze the impact of initial ovality, inner pipe thickness, and outer pipe thickness on the maximum lateral load of the sandwich pipe. The findings demonstrated that under coupled loads, sandwich pipes exhibited two types of buckling behavior: local buckling and buckling propagation. Moreover, as the external pressure increased, the buckling tendency in sandwich pipes transited from local buckling to buckling propagation. To enhance the capacity of sandwich pipes, there were two strategies proposed: increasing the thickness of the outer pipe and then reinforce the inner pipe to improve overall strength. Finally, based on an analysis of sandwich pipe applications up to 5000 m water depths, the sandwich pipe structure were proposed suitably for various water depths. • We found the higher pressure levels facilitated buckling propagation and collapse of the sandwich pipe. • The wall thickness of the outer pipe does not always result in an increase in the strength of the sandwich pipe. • We recommended to preferentially select a sandwich pipe with a larger outer pipe wall thickness. [ABSTRACT FROM AUTHOR]

It is crucial to reveal the dent deformation mechanism of the sandwich pipe (SP) for the dent evaluation of damaged offshore SPs. This study aimed to explore the difference in dent characteristics between sandwich pipes' inner and outer tubes subjected to lateral loads. Quasi-static lateral denting tests are carried out to investigate the denting resistance and the indentation characteristics of SPs with the ends fixed. The finite element method is used to simulate the development of SP dent in the installation, operation, and shutdown stages. The dent depth and dent strain of the inner and outer tubes are examined and compared. Parametric studies are performed to clarify the influence of material properties, geometric configuration, and interlayer friction on the difference in dent characteristics between the inner and outer tubes. The research demonstrates that the relative difference in dent characteristics between the inner tube and the outer tube is closely related to the hollow ratio, thickness-to-radius ratio, material steel grade of the inner tube and the outer tube, and the interaction between the layers. The findings show that the current dent evaluation criteria need to be improved to provide practical dent evaluation for the dented SPs. • The inner tube dent depth ratio is generally lager than the outer tube. • The dent strain of the outer tube is much higher than that of the inner tube. • Geometric parameters are the most crucial factors affecting the dent characteristics. • The current dent evaluation criteria needs to be improved for sandwich pipes. [ABSTRACT FROM AUTHOR]

In this study, the α-Fe 2 O 3 /MIL-53(Fe) composite was successfully designed and developed through a solvothermal method as a photo-Fenton catalyst and for the degradation of tetracycline hydrochloride (TC-HCl). The results show that the prepared composite exhibits superb performance for the degradation of TC-HCl ascribing to the synergistic effect between MIL-53(Fe) and α-Fe 2 O 3. And the formation of heterojunction structure is beneficial to reducing the band gap, enhancing the absorption of visible light, and improving the separation and transportation of photo-induced carriers. Moreover, this heterojunction structure can be formed without annealing treatment. The effects of pH, H 2 O 2 consumption and catalyst dosage on the degradation of TC-HCl are also investigated. The optimum conditions for target pollutant degradation were investigated according to the response surface methodology (RSM) result based on a central composite design (CCD). A possible mechanism of degradation of TC-HCl is proposed according to the main active radical that existed in the reaction process. This work provides a novelty perspective and in-depth and independent insight for the photo-Fenton mechanism of heterojunction structure modified MOFs material. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, micro-spherical β-NiOOH/FeMoO 4 with multiple active sites was prepared by one-step solvothermal method and its performance in the photo-Fenton system was investigated. The results indicate that highest degradation efficiency of methylene blue (MB) was obtained when the molar ratio of nickel to iron was 1:2.5. In addition, composites were assessed for its degradation performance for MB by adjusting the concentration of H 2 O 2 , pH and catalyst dosage. The pseudo-first-order kinetic rate constant of MB degradation in β-NiOOH/FeMoO 4 catalyzed photo-Fenton system was 0.234 min−1 about 5 folds that of pristine FeMoO 4 micro-sphere. The degradation mechanism of MB was deduced by active species quenching experiments and technology of coumarin fluorescent probe. And its degradation pathway was proposed by LC-MS identifying reaction intermediates produced during photo-Fenton catalysis. Recycling tests have confirmed excellent stability of β-NiOOH/FeMoO 4 composite. In conclusion, this study demonstrates the β-NiOOH/FeMoO 4 composite is a promising heterogeneous photo-Fenton catalyst. [Display omitted] • Microspheres with special particle accumulation surface structure were prepared. • The doped of Fe enables NiOOH to crystallize stable into β phase. • The degradation efficiency of MB can reach 99.5% in 18 min. • The generation potential of ·OH was indirectly determined by the coumarin fluorescence probing technique. [ABSTRACT FROM AUTHOR]

[Display omitted] • The right amount of cobalt ions could induce the formation of Fe 1-x S. • 100 mL orange II solution (30 mg/L) was degraded to 99.9% within 15 min. • OH and h+ played an important role in the photo-Fenton-like process. • FeS 2 -Fe 1-x S exhibited excellent stability and high catalytic degradation activity for other dyes. It is a challenge to develop heterogeneous Fenton-like catalysts with excellent performance and stability in the field of wastewater treatment. In this work, the FeS 2 -Fe 1-x S heterostructure catalyst was prepared by solvothermal method through adding cobalt element to change the particle nucleation process and inhibit the transformation process of pyrrhotite (Fe 1-x S) phase to pyrite (FeS 2) phase. Then, a series of experiments were devised to clarify the catalytic activity of FeS 2 -Fe 1-x S heterostructure. The degradation experiments exhibited that 99.9% degradation efficiency was achieved for 30 mg/L orange II solution within 15 min at the conditions of 0.2 g/L FeS 2 -Fe 1-x S, 2 mM H 2 O 2 and pH = 3.0. In addition, the reusability of the FeS 2 -Fe 1-x S catalyst was also investigated and the result displayed that degradation efficiency of orange II can reach 95.2% after eight cycles. The degradation of orange II was enhanced by Fenton reaction between FeS 2 -Fe 1-x S and dissolved oxygen, which could smoothly release Fe2+ and Fe3+ for the activation of H 2 O 2 to produce more hydroxyl radicals. Finally, the degradation pathway of orange II was proposed by detecting intermediates produced in FeS 2 -Fe 1-x S/H 2 O 2 photo-Fenton-like system by liquid chromatography-mass spectrometry (LC-MS). In short, FeS 2 -Fe 1-x S is a promising catalyst for removing the organic pollutants from solutions. [ABSTRACT FROM AUTHOR]

• The Orange II degradation efficiency attained to 98.9% within 15 min. • OH played an important role in the Cu 2 O(SO 4)-Fe9/H 2 O 2 Fenton-like process. • The degradation rate constant of Cu 2 O(SO 4)-Fe9 is 9.33 and 4.07 times of Cu 2 O(SO 4) and α-Fe 2 O 3 , respectively. • Orange II degradation is conducted through destruction of conjugated structures and mineralization. Hematite (α-Fe 2 O 3), as one of Fenton reagents, is widely investigated for the treatment of wastewater in the field of advanced oxidation processes (AOPs). Considering the fast charge carrier recombination of hematite (α-Fe 2 O 3), we have successfully synthesized a novel and high active heterogeneous Fenton catalyst α-Fe 2 O 3 /Cu 2 O(SO 4) for the degradation of organic pollutants. The results show that the as-obtained Cu 2 O(SO 4)-Fe9 composite exhibits excellent degradation properties of Orange II. 98.9% degradation rate was achieved for 100 mL of 50 mg/L Orange II solution in the condition of 0.3 g/L Cu 2 O(SO 4)-Fe9 catalyst, 3 mM H 2 O 2 and pH = 3.5. The degradation rate constants of Cu 2 O(SO 4)-Fe9 in the photo-Fenton-like system are 9.33 and 4.07 times of Cu 2 O(SO 4) and α-Fe 2 O 3 , respectively. In addition, the mechanism and pathway for the degradation of Orange II were proposed. The scheme of combining copper-based oxysulfate Cu 2 O(SO 4) with hematite (α-Fe 2 O 3) could improve the efficiency of charge carrier separation, which will further enhance the catalytic activity and expand its application in water purification. [ABSTRACT FROM AUTHOR]