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The detection rate and concentration of fluoroquinolone antibiotics in wastewater have experienced an upward trend in recent years, primarily attributed to their extensive utilization. The effects of fluorine substituents on the degradation of fluoroquinolone and the associated mechanism remain uncertain. This study aimed to assess the efficacy of freeze-activated periodate (Freezing/PI) in the degradation of three different fluoroquinolones with varying quantities of fluorine. Additionally, the study analyzed the underlying mechanism using density functional theory (DFT) calculations. The results showed that under the optimal experimental conditions (IO 4 -=0.05 mM, pH=3.0, freezing temperature=-25 ℃), the degradation rate of fluoroquinolone antibiotics reached 90.1% after 45 minutes of Freezing/PI process. Fluoroquinolone is primarily oxidized by non-free radical pathway, while co-existing substances such as HCO 3 - and humic acid inhibited the degradation of fluoroquinolone. The primary reaction pathway for the degradation of fluoroquinolone involves the cleavage and detachment of the piperazine ring. The reaction rates of the fluorine substituents at the C-7 and C-9 positions of lomefloxacin and flerofloxacin on the piperazine ring were found to be higher than that of ciprofloxacin. This can be attributed to the presence of synergistic electron conjugation. The objective of this experiment was to analyze additional influencing factors of the Freezing/PI process. The impact of the quantity of fluorine substituents on the reaction and the degradation of fluoroquinolone by free radical pathway were elucidated using DFT. This analysis offers insights into the potential application of the process in low-temperature environments and the management of fluorinated organic compounds. [Display omitted] • Three FQs were successfully degraded by Freezing/PI. • According to mass spectrometry, FQs with more F will degrade faster. • Piperazine ring cleavage and defluorination rates were calculated used IRC. • The amount of F significantly affects the cleavage rate of piperazine rings. [ABSTRACT FROM AUTHOR]

[Display omitted] • β -lonone, citral, γ -terpinene and myrcene inhibit the growth of A. alternata. • Biotransformation of monoterpenoids was achieved by fermentation of A. alternata. • These biotransformations were related to self-protective mechanism of A. alternata. • Combination of P450 enzyme inhibitor could enhance the activity of monoterpene. Alternaria alternata is a critical plant pathogen, and the black spot caused by this fungus is the main cause of crop loss. In this study, four monoterpenes commonly found in plant essential oils, β -lonone, citral, γ -terpinene and myrcene, were found to possess a two-way interaction relationship with A. alternata. Four monoterpenes exhibited moderate inhibitory activities against A. alternata with MIC values of 128, 256, 512 and 256 μg/mL, respectively. However, when the concentration of monoterpenes in the culture medium was reduced to 1/4 MIC, A. alternata could facilitate the biotransformation of the aforementioned four monoterpenes by hydroxylation, dihydroxylation or carboxylation. These biotransformations were verified to be promoted by the P450 enzyme. Considering that none of the converted products showed inhibitory activity against A. alternata , these transformations were hypothesized to be self-protective mechanism of A. alternata. Expectedly, the combined use of P450 enzyme inhibitors and monoterpenes exhibited stronger antifungal activities, and could significantly inhibited black spot development in tomatoes. This work provides a reference for the development of effective antifungal agents. [ABSTRACT FROM AUTHOR]

Highlights • Piecewise function models for establishing constitutive equations of AZ91 alloy are proposed. • New functions for describing material constants in constitutive equations are proposed. • Piecewise function models show higher precision and good capability for describing constitutive equations. • Description of nonlinear function is better for predicting variation of flow stress after the peak value. Abstract The hot deformation behavior of AZ91 magnesium alloy was studied using single-pass compression experiments within a temperature range of 473–623 K and strain rate of 0.001–1 s−1. The flow stress first increases to a peak value with the work hardening, and then decreases slowly during dynamic softening. New piecewise function models were proposed to describe the constitutive equations of AZ91 magnesium alloy of stress–strain curves. Meanwhile, new methods to obtain the material constants k, C 1 and C 2 were proposed to predict accurately the flow stress corresponding within the range of strain from peak values to end based on the phenomenological representation of stress–strain curves in the second stage. Furthermore, the strain-compensated Arrhenius equation model was also used to describe the constitutive equations of plastic stage. The results predicted by these models are in good agreement with the measured data in the second stage, and the maximum average relative error of the predicted results is less than 10%. The strain-compensated Arrhenius equation model shows good capability under certain conditions, but it has lower fitting precision and also needs consume much time to obtain more material constants compared with piecewise function models. The piecewise function models show higher precision; the average relative error of the predicted results is less than 3% when the stress–strain curves in the second stage are described as nonlinear functions. These proposed methods for obtaining material constants k, C 1 and C 2 are valid and the piecewise function models are significant for establishing constitutive equations of metal alloys in hot deformation processes. [ABSTRACT FROM AUTHOR]

Development of efficient and metal-free electrocatalysts toward hydrogen evolution reaction (HER) is of great significance for the renewable energy conversion and storage technologies. Heteroatom doping, especially two heteroatoms co-doping, is one of the most effective strategies to improve the catalytic activity of carbon-based electrocatalysts. Here, we reported that the plasma-etching could produce additional structural defects on N, S co-doped graphene (NSG), which further improved the HER activity of NSG. It was demonstrated that the synergetic coupling effect of N, S co-doping and plasma-induced structural defects could maximize the number of exposed active sites and significantly enhance the HER activity of graphene in both acidic and alkaline media. This study thus indicates that combining defect engineering with heteroatoms co-doping is an efficient strategy for dramatically improving the HER activity of graphene. [ABSTRACT FROM AUTHOR]

• China's technical progress is biased towards ICT capital and fossil energy. • ICT capital is substitute for fossil energy and complementary to non-fossil energy. • Carbon reduction curve of Subs-KiF is N-shaped, but it's the opposite in Subs-KiN. • Carbon reduction potential of ICT are not fully realized for low carbon economy. Information and communications technology (ICT) investment is beneficial for achieving economic growth within a low carbon system, as the substitution or complementation of ICT to energy offset increased carbon emissions. Based on Chinese provincial panel data during 2000-2018, we incorporate ICT capital as a separate factor to the trans-log production function and identify factor substitution to study ICT's carbon reduction effects. The results show that China's technical progress is more biased towards non-ICT capital, ICT capital and fossil energy, deviate from non-fossil energy and labor. The carbon reduction effect of ICT is manifest by its substitution with fossil energy (0.528) and complementation to non-fossil energy (-0.072), which is comprehensive improvement in both energy productivity and energy structure. Besides, the threshold model reveals an "N" curve carbon reduction effect of substitution elasticity between ICT and fossil energy, whereas it is the opposite for non-fossil energy, and the current substitution elasticities are both in the interval that undermines carbon reduction. This paper confirms ICT's potential in carbon reduction, while this potential is not amplified in production modes of most provinces, and future efforts are required for its suitable match with low carbon transformation. [ABSTRACT FROM AUTHOR]

Abstract: Olivine structured LiFePO4/C cathode was synthesized via a freeze-drying route and followed by microwave heating with two kinds of carbon sources: PEG-4000 (organic) and Super p (inorganic). XRD patterns indicate that the as-prepared sample has an olivine structure and carbon modification does not affect the structure of the sample. Image of SEM shows a uniform and optimized particles size, which greatly improves the electrochemical properties. TEM result reveals the amorphous carbon around the surface of the particles. At a low rate of 0.1C, the LiFePO4/C sample presents a high discharge capacity of 157.8mAhg−1 which is near the theoretical capacity (170mAhg−1), and it still attains to 149.1mAhg−1 after 200 cycles. It also exhibits an excellent rate capacity with high discharge capacities of 143.2mAhg−1, 137.5mAhg−1, 123.7mAhg−1 and 101.6mAhg−1 at 0.5C, 1.0C, 2.0C and 5.0C, respectively. EIS results indicate that the charge transfer resistance of LiFePO4 decreases greatly after carbon coating. [Copyright &y& Elsevier]

Cinnamic acid derivatives (CAs), which have proven to be versatile components, are present in abundance in biologically active natural products, and are widely used as intermediates in the manufacture of pharmaceuticals, and chemicals. The presence of cis - and trans -CAs created difficulties for natural product and organic synthetic studies. A highly efficient method that utilized iodine to entirely convert cis - CAs into their trans -forms was developed to solve this problem. The mechanism of study revealed this conversion occurred via an anti -diiodo intermediate. [ABSTRACT FROM AUTHOR]

A chemical investigation of the endophytic fungus Diaporthe destruens from the Hernandiaceae plant Illigera orbiculata C. Y. Wu collected from southern Yunnan Province, China, led to the isolation of six undescribed compounds, including two azaphilone analogs, which are a pair of epimers (13 R- hydroxy-chermesinone A and 13 S- hydroxy-chermesinone A); a pyrrole derivative (1-(4-(methoxymethyl)-1H-pyrrol-3-yl)ethan-1-one); an isoindolone derivative (4-hydroxy-6-methoxyisoindolin-1-one); a benzylbenzene derivative (destruensine A) and a conjectural fragment of polyketide ((2 R ,4 R)-2-(methoxymethyl)pentane-1,4-diol) along with nine known compounds. Their structures were elucidated by spectroscopic methods and HRESIMS, and the absolute configurations were further confirmed by electronic circular dichroism (ECD) and chemical derivatization. The antimicrobial activities, anti-acetylcholinesterase activities, antiproliferation, and NO production inhibitory effects of compounds 1 – 15 were evaluated. Fifteen specialised products, including six undescribed structures, were obtained from Diaporthe destruens hosted in Illigera orbiculata. Their bioactivities were evaluated. [Display omitted] • Six undescribed compounds were isolated from the fungus Diaporthe destruens. • The absolute configurations of the undescribed compounds were established. • The bioactivities of the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]

The complexity of socioecological systems (SES) has posed a persistent challenge to the development of methods for diagnostic and prognostic analyses of global change. We developed a high dimensional statistical framework where cluster analysis was used to characterize regional landscape typologies and those typologies are linked to the outcome of interest through regression modeling. For demonstration, we applied the framework to agroecosystem of the United States Gulf Coast to evaluate the determinants of spatial variability in crop yield. Regional biophysical typologies (BPT; integrated climate, soil, and topography clusters) and socioecological typologies (SET; BPT combined with socioeconomic clusters) were developed. The SET corn model (R2 = 0.89) outperformed the BPT corn model (R2 = 0.72) and a county fixed-effect model (R2 = 0.53), which reflects the socioeconomic influence over agricultural productivity. The SET model also showed similar predictive skill for soybean and cotton yield. Therefore impact analysis for agroecosystems can lead to incorrect conclusions if biophysical factors are not examined jointly with socioeconomic factors. [ABSTRACT FROM AUTHOR]

Two new peroxy fatty acids, thermalic acids A ( 1 ) and B ( 2 ), together with eight known compounds, (3 β )-methyl-3-hydroxy-urs-11-en-28 oate ( 3 ), luteolin ( 4 ), quercetin ( 5 ), 3-methoxyquercetin ( 6 ), ophioglonol ( 7 ), ophioglonol 4′-O- α -D-glucopyranoside ( 8 ), pedunculosumoside B ( 9 ), syringol ( 10 ), were isolated from the herba of Ophioglossum thermale Kom. The structures of 1 and 2 were identified by HRESIMS, EIMS, 1D and 2D NMR, and electronic circular dichroism (ECD) spectra. Both two acids exhibited potential antibacterial activities against Staphylococcus aureus , Bacillus subtilis , and Escherichia coli . This is the first report of peroxy fatty acids isolated from herbaceous plants of Ophioglossaceae. [ABSTRACT FROM AUTHOR]

• Nonalcoholic fatty liver disease (NAFLD) is the most frequent liver disease. • 249 differentially expressed genes and one key gene showed significant association with NAFLD. • 514 differentially expressed genes and 11 hub genes closely associated with progression from NASH to HCC. • One key gene (AKR1B10) was differentially expressed between the NASH and NAFL groups. • Associated DEGs and genes can serve as diagnostic or therapeutic targets for NASH. Nonalcoholic fatty liver disease (NAFLD) is the most frequent liver disease and associated with a wide spectrum of hepatic disorders ranging from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma (HCC). NASH is projected to become the most common indication for liver transplantation, and the annual incidence rate of NASH-related HCC is 5.29 cases per 1000 person-years. Owing to the epidemics of NAFLD and the unclear mechanism of NAFLD progression, it is important to elucidate the underlying NAFLD mechanisms in detail. NASH is mainly caused by the development of NAFL Therefore, it is also of great significance to understand the mechanism of progression from NAFL to NASH. Gene expression chip data for NAFLD and NASH were downloaded from the Gene Expression Omnibus database to identify differentially expressed genes (DEGs) between NAFLD and normal controls (called DEGs for NAFLD), as well as between NASH and normal tissue (called DEGs for NASH-Normal), and between NASH and NAFL tissue (called DEGs for NASH-NAFL). For DEGs for the NAFLD group, key genes were identified by studying the form of intersection. Potential functions of DEGs for NASH were then analyzed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. A protein–protein interaction network (PPI) was constructed using the STRING database. A total of 249 DEGs and one key gene for NAFLD were identified. For NASH-Normal, 514 DEGs and 11 hub genes were identified, three of which were closely related to the survival analysis of HCC, and potentially closely related to progression from NASH to HCC. One key gene for NASH-NAFL (AKR1B10) was identified. These genes appear to mediate the molecular mechanism underlying NAFLD and may be promising biomarkers for the presence of NASH. [ABSTRACT FROM AUTHOR]