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Graphene nanosheets (GS) were prepared by ultrasonic exfoliation of bulk graphite in N-methyl-2-pyrrolidone with the assistance of sodium pyrophosphate. The obtained GS suspension was modified on a glassy carbon electrode (GS/GCE), and then functionalized at different voltages (e.g. 1.0, 1.4 and 1.6 V) for 2 min in pH 7.0 phosphate buffer. The electrochemically functionalized GS/GCE (i.e. EGS/GCE) possesses more oxygen-containing groups and a higher defect level. More importantly, the active response area, electron transfer ability and interface adsorption capacity of the EGS/GCE enhanced remarkably. The possible mechanism of the performance enhancement is discussed, and the sensing application of the EGS/GCE in the detection of nitrofurazone (NFZ) is investigated. Compared with the GS/GCE, the EGS/GCE is much more active for NFZ oxidation and greatly increases the detection sensitivity. As a result, a highly sensitive electrochemical detection method has been developed for NFZ, with a detection limit of 2.1 nM. The practical application of the EGS/GCE was tested in fish meat samples, showing good accuracy and feasibility. [ABSTRACT FROM AUTHOR]

A sol-gel method is presented to synthesize molecularly imprinted polymers (MIPs) composed with a copper-based metal-organic framework (referred to as MIP/HKUST-1) on a paper support to selectively recognize tetrabromobisphenol A (TBBPA). The imprinting factor is 7.6 and the maximum adsorption capacity is 187.3 mg g−1. This is much better than data for other MIPs. The degradation of TBBPA is introduced in the procedure. Due to the selective recognition by the MIP, the enzyme-mimicking properties of HKUST-1 under the MIP layer became weak due to the decrease of residue imprinted cavities. And adsorbed TBBPA can be degraded under consumption of hydrogen peroxide (H2O2). The combined effect of H2O2 and HKUST-1 cause the coloration caused by catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine to become less distinct. This amplification strategy is used for the ultrasensitive and highly selective colorimetric determination of TBBPA. The gray intensity is proportional to the logarithm concentration of TBBPA in the range of 0.01–10 ng g−1. The limit of detection is as low as 3 pg g−1, and the blank intensities caused by TBBPA analogues are <1% of that caused by TBBPA at the same concentration, this implying excellent selectivity. The spiked recoveries ranged from 94.4 to 106.6% with relative standard deviation values that were no more than 8.6%. Other features include low costs, rapid response, easy operation and on-site testing. [ABSTRACT FROM AUTHOR]

In this paper, we assessed the suitability of temperature derivatives for China through modeling. We assumed that if the physical dynamics of temperature of some cities are identical, then the same types of temperature derivatives can be used in these cities. Nearly twenty years temperature data of forty-seven cities with traded temperature derivatives on the Chicago Mercantile Exchange Group (CME) and seven Chinese cities were collected and analyzed in a two-step approach. Firstly, the AR-EGARCH model capturing the shock asymmetry of the volatility of temperature is used to simulate the dynamics of temperature of the cities. Secondly, the temperature of the cities are classified through cluster analysis based on model parameters from the AR-EGARCH model. The results showed that the fitting effect of the AR-EGARCH model is very good, and only a few cities did not display the shock asymmetry. The model for Nanjing fitted well into one of the categories of the cities in the CME; but the other six Chinese cities belong to new categories, which are different from the cities in the CME. We concluded that HDD and CAT in Europe and CAT ∗ in Japan can be used directly in Nanjing, but the existing temperature derivatives in CME were unsuitable for the other six Chinese cities. Recommendations for the establishment of weather derivatives market in China have been proposed. • We explored whether temperature derivatives traded on CME are suitable to China. • Cluster analysis in form of model parameters from the AR-EGARCH model is used to classify temperature data. • Asymmetry of the volatility of the temperature is confirmed according to the AR-EGARCH model. • HDD and CAT in Europe and CAT ∗ in Japan can be used directly in Nanjing of China. [ABSTRACT FROM AUTHOR]

Imazamox, one of imidazolinone herbicides, was found can chelate with Fe(II) in surface water enviroment to form imazamox-Fe(II) complex. By using EDS elemental analysis, HR-ESI-MS and JOB's curves, the complex was characterized as two molecule imazamox coordinated with one ferrous iron, besides, multiple analytical and spectroscopic methods, such as UV-vis, FT-IR, Raman and control experiments were conducted, the function group involved in coordination was determined, and the structure detail of imazamox-Fe(II) complex was proposed as four N atoms from two different imazamox ions (two N atoms from two pyridyl rings and the other two N atoms from two oxo-imidazole rings) and two O atoms from two different carboxylate groups to complete a 6-coordinate mode of Fe(II). Based on the finding, the influence of imidazolinone herbicides on available ferrous iron in soil was also discussed. [ABSTRACT FROM AUTHOR]

This study presents an experimental investigation of co-pyrolysis of discarded rubber and plastics in a tube furnace. The properties of the pyrolysis oil and solid residue under various blending ratios of rubber and plastics were investigated. The impacts of the stalk additive and the heating rate on the pyrolysis oil yield and feedstock-to-oil energy conversion efficiency (FOECE) were studied. Compared with the pyrolysis of rubber or plastics separately, the co-pyrolysis of rubber and plastics produced a higher oil yield with a higher oil heating value. When the mass fraction of the rubber was 60 wt%, the pyrolysis oil yield and FOECE reached their maximum values. When adding 10% stalk additive at a rubber-to-plastics ratio of 4:1, a higher oil yield was achieved, and the oil yield increased by 10.3 wt%, where the heating value of the pyrolysis oil reached 39.93 MJ kg −1 . The stalk additive only had a slight impact on the solid residue and the completeness of the pyrolysis reactions. The stalk additive increased the FOECE and postponed the highest yield point to the 80 wt% rubber blend because the greater volatility promoted the pyrolysis reaction and the production of condensable gaseous components. A higher heating rate improved the oil yield. According to the elemental analysis, a small fraction of sulfur existed in the oil. The stalk additive increased the H/C ratio in the oil. Through the GC–MS analysis, the primary components in the pyrolysis oil from the rubber and plastics blend were identified as alicyclic hydrocarbons and aromatics, whereas the oxygen-rich stalk additive increased the contents of alcohols, esters, and ketones. Overall, the stalk additive significantly improved the yield and the FOECE when co-pyrolysis of rubber/plastic blends was performed. [ABSTRACT FROM AUTHOR]

• Review of sample preparation methods for halogen IC analysis in inorganic matrices. • Comparison of inorganic sample digestion methods. • Pros and cons of analytical techniques for nonmetals analysis. • The roles, limitations, and prospects of IC in inorganic sample analysis for environmental studies. The inorganic matrices such as metal concentrates, steel, cement, glass, clay, coal, graphite, rocks and sediments, ores etc. play a pivotal role in infrastructure development, transportation, and energy. The presence of non-metallic elements particularly halogens influence their quality, processing cost, and environment dynamics. The analysis of non-metals in such matrices is critically challenging due to their hardness, rigidity, and non-digestibility. This comprehensive review provides a critical comparison of various sample preparation methods in conjunction with pros and cons of advanced techniques for the detection of non-metals in complex matrices, particularly focusing on ion chromatography. Moreover, the review also addresses the challenges related to the enrichment and automation of non-metals analysis. In addition, the previous literature on non-metals determination in diverse range of inorganic matrices has been tabulated for the first time. These insights are intended to guide researchers, quality control analysts, environmental scientists, and policymakers in enhancing pollution monitoring and control strategies. [ABSTRACT FROM AUTHOR]

Abstract: Simple, reliable and sensitive analytical methods to determine the anions, such as fluoride, monofluorophaosphate, glycerophosphate related to anticaries are necessary for basic investigations of anticaries and quality control of dentifrices. A method for the simultaneous determination of organic acids, organic anions and inorganic anions in the sample of commercial toothpaste is proposed. Nine anions (fluoride, chloride, nitrite, nitrate, sulfate, phosphate, monofluorophaosphate, glycerophosphate and oxalic acid) were analyzed by means of ion chromatography using a gradient elution with KOH as mobile phase, IonPac AS18 as the separation column and suppressed conductivity detection. Optimized analytical conditions were further validated in terms of accuracy, precision and total uncertainty and the results showed the reliability of the IC method. The relative standard deviations (RSD) of the retention time and peak area of all species were less than 0.170 and 1.800%, respectively. The correlation coefficients for target analytes ranged from 0.9985 to 0.9996. The detection limit (signal to noise ratio of 3:1) of this method was at low ppb level (<15ppb). The spiked recoveries for the anions were 96–103%. The method was applied to toothpaste without interferences. [Copyright &y& Elsevier]

Abstract: A single-column method for the simultaneous determination of common cations and transition metals in real samples is proposed in this paper. Eleven cations (copper, lithium, sodium, ammonium, potassium, cobalt, nickel, magnesium, calcium, strontium and zinc) were separated and analyzed by means of ion chromatography using an isocratic elution with 2.5mM methane sulfonic acid and 0.8mM oxalic acid as mobile phase, IonPac SCS1 (250mm×4mm I.D.) as the separation column and non-suppressed conductor detection. Optimized analytical conditions were further validated in terms of accuracy, precision and total uncertainty and the results showed the reliability of the IC method. The relative standard deviations (RSDs) of the retention time and peak area were less than 0.04 and 1.30%, respectively. The coefficients of determination for cations ranged from 0.9988 to 1.000. The method developed was successfully applied to determination of cations in samples of beer and bottled mineral water. The spiked recoveries for the cations were 94–106%. The method was applied to beer and beverage without interferences. [Copyright &y& Elsevier]

Abstract: Selenium (Se) plays an important role in cancer-prevention. Silkworm pupas have been used as a Chinese traditional medicine since ancient time. In order to find effective carcinostatic agents, Se-rich amino acids were extracted from Ziyang silkworm pupas. The Se content of Ziyang pupas was measured to be 215 times higher than that of Luoyang normal ones, and the majority of Se was stored in proteins. Composition analysis showed that Se-rich amino acids from Ziyang pupas had higher amounts of selenomethionine, methionine, cystine, and tyrosine than normal amino acids from Luoyang pupas which were rich in amino acids containing alkyl side chains. When cultured with human hepatoma cells SMMC-7721, Se-rich amino acids at concentrations of 0.5, 1.5, and 2.5 μmol L−1 Se significantly and dose-dependently inhibited cell viability, induced changes in cell morphology and cycle, and caused cell apoptosis. On the contrary, normal amino acids did not show any inhibitory effect on SMMC-7721 cells. Sodium selenite or selenomethionine at the same Se concentrations only slightly inhibited the hepatoma cells. Mechanism study showed that selenium-rich amino acids could increase the generation of intracellular reactive oxygen species (ROS) concentration-dependently. Antioxidant N-acetylcyteine partially inhibited the increase of ROS. Those results suggested that Se-rich amino acids were effective carcinostatic agents compared with sodium selenite and selenomethionine. The mechanism for their hepatoma-inhibitory effects was the induction of cellular apoptosis through ROS generation. [Copyright &y& Elsevier]

• Template-probe double imprinting can enhance the accessibility of the probe to catalytic interface. • H-GNs/filter paper can initiate the surface polymerization of MIPs • Anti-Tg antibodies and sample matrix did not affect the detection of Tg. • A simple, low-cost and sensitive paper-based sensor for the label-free colorimetric detection of Tg (660KD, protein) is developed for the first time. Thyroglobulin (Tg) is an important index for the surveillance of differentiated thyroid carcinoma, and yet sensitive and specific protein detection still faces challenges in both biomedical research and clinical diagnosis. We described a novel approach to synthesize molecular imprinting polymers (MIPs)/hemin-graphene nanosheets (H-GNs) composites on the paper, using Tg and 3,3′,5,5′-tetramethylbenzidine (TMB, probe) as double templates. H-GNs with intrinsic properties can initiate the free-radical polymerization to prepare MIPs and catalyze the coloration of peroxidase substrates (TMB) for colorimetric detection. Template-probe double imprinting strategy enhanced the accessibility of the probe to the catalytic interface without interfering the specific recognition of template molecule. Under the optimized conditions, the gray intensity was proved to be proportional to the concentration of Tg in the range of 0.7-100 ng mL-1 with a detection limit of 0.1 ng mL-1 (1.5 fM). Anti-Tg antibodies and sample matrix did not affect the determination of the target protein, nor did they enhance the background noise. The use of paper-based device exhibited the advantages of low cost, easy handling and portability. It was supposed to be applied for Tg determination in serum to evaluate persistent or recurrent differentiated thyroid carcinoma. [ABSTRACT FROM AUTHOR]

Personal care and cosmetic products (PCPs) are the primary exposure pathway of humans to parabens and their safety has become a public concern. However, sample pretreatment of PCPs is a great challenge due to their complexities and diversity. In this study, epoxide modified molecularly imprinted polymers (MIPs) were synthesized using ethylparaben as a template, methacrylic acid and isobutyl vinyl ether as co-monomers and glycidilmethacrylate as a post-modified monomer. MIP layer open-tubular tubes were prepared by modifying branched polyethylenimine and then grafting MIPs onto the inner surface of Teflon capillary tubes. The tube was coiled to effectively increase mass transfer and coupled to an HPLC-UV system for parabens detection in PCPs. Matrix interference was significantly decreased while efficient enrichment and recoveries were obtained. Under optimized conditions, the linear range for parabens detection was 0.5–600 ng mL−1 with detection limits of 0.2 to 0.3 ng mL−1. The system was used to study the contents of parabens in popular PCPs. The concentrations of parabens in 108 PCPs ranged from <0.5 ng g−1 to 2856 μg g−1 with geometric mean of 250.3 μg g−1. Almost all of the products contained at least one kind of parabens; methyl paraben (geometric mean: 182.9 μg g−1) and n-propyl paraben (geometric mean: 42.5 μg g−1) were the predominant compounds had been found in the samples. This method could be useful for human exposure assessment towards parabens. Unlabelled Image • The epoxide modified MIPs were grafted on the inner surface of capillary tube. • The tube was coiled to effectively improve the extraction efficiency. • The coiled MIP-OT capillary tube was constructed to selectively extract parabens. • The coiled MIP-OT capillary tube exhibited high cleanup efficiency and recovery. [ABSTRACT FROM AUTHOR]

An analysis method was established to determine 14 organophosphorus ester (OPE) flame retardants in fall protection equipment by combining accelerated solvent extraction (ASE) and solid-phase extraction (SPE) with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The ASE parameters were optimized as follows: static extraction with acetonitrile at 80°C for 5 min for two cycles. The combined extract was purified with the ENVI-18 cartridge before further analysis. A HILIC column was used to separate the OPEs using an acetonitrile/water mixture as the mobile phase with the detection by the electrospray ionization mass spectrometry, which was operated under the positive mode. Under optimized conditions, the limit of detection for the target OPEs ranged in 0.015–1.33 ng/g, with a spike recovery of 71.6%–114% and a relative standard deviation of 0.8%–11.2%. The developed method was used to analyze OPEs in fall protection equipment (safety helmets and ropes), where OPEs were all detectable. Safety ropes displayed a higher concentration of OPEs than ones in safety helmets, with the pollutants being mainly triphenyl phosphate, 2-ethylhexyl diphenyl phosphate (EHDPP), tri(2-ethylhexyl) phosphate, and tri-n-butyl phosphate in the range of 11.07 ng/g‒815.53 ng/g. The EHDPP was the dominant compound in safety helmets with the concentration from 26.84 to 95.29 ng/g, while the other OPEs in safety helmets were lower than 5.136 ng/g. The potential health and environmental risks of these fall protection equipment during their use and disposal call for further attention. [ABSTRACT FROM AUTHOR]

A simple, cost‐effective, sensitive, and quick method for the determination of nitenpyram and its metabolite 6‐chloronicotinic acid in environmental samples was developed by coupling an ion chromatograph with a fluorescence detector and a post‐column photochemical reactor. This developed analytical method involved a rapid sample extraction by modified and miniaturized quick, easy, cheap, effective, rugged, and safe method followed by isocratic ion chromatographic separation of nitenpyram and 6‐chloronicotinic acid into an IonPac™ AS11‐HC column protected by IonPac™ AG11A guard column by running 30 mM NaOH + 10% acetonitrile mobile phase. A homemade post‐column photochemical reactor was also integrated with the ion chromatographic system for online transformation of both analytes into their respective highly fluorescent photoproduct in basic media without using an extra pump. The developed method was validated by following SANTE/11945/2015 guidelines on analytical quality control and validation procedures. The method showed a good linear response (r > 0.999), improved limit of detection (0.101–0.132 μg/L), minimum or no matrix effect, excellent recoveries (90.2–100.10%) and relative standard deviations were found to be ≤6.50%. [ABSTRACT FROM AUTHOR]

Sapium sebiferum (L.) Roxb, has a long history of being used as an oil-producing plant due to its high oil content of the seeds. In recent years, the seed oil of this tree has gained considerable interest as an ideal material to produce biodiesel. To optimize the harvesting time of the seed, we tracked the variation of chemical constituents of seed oil harvested in different days (from October 1, 2021 to November 30, 2021). Firstly, the chemical constituents and fatty acid profile of external wax and internal kernel oil were studied, using nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS) as structure elucidation tools. Secondly, the constituent variation of external wax and kernel oil from different harvesting time was analyzed by 1H NMR and chemometrics tool. The results showed that unsaturated fatty acids in the kernel oil accumulated during harvesting time, while the external wax was progressively oxidized to formic acid due to exposure to air. Since the kernel oil was seal off from oxygen, no oxidation process was observed in it. Considering for the quality and total weight of lipids for biodiesel manufacturing, we suggest that the optimal harvesting time for seeds of S. sebiferum should be early November, when the fruit undergo complete cracking and the seeds are initially exposure to air. This information is practically helpful for optimizing the production of biodiesel from S. sebiferum and other similar oil-producing plants. • The chemical constituents variation of the seeds of the Chinese tallow tree at different harvesting time was tracked. • Unsaturated fatty acids in the kernel oil accumulated during harvesting time. • The external wax was progressively oxidized to formic acid due to exposure to air. • The optimal harvesting time for seeds of the Chinese tallow tree should be early November. [ABSTRACT FROM AUTHOR]

Volatile organic compound (VOC) removal by photocatalytic oxidation (PCO) is the practical and economical process to reduce air pollutants. Many conditions, such as temperature, initial concentration of VOC, relative humidity, gas flow rate, and light intensity, affected this process. Therefore, finding the optimal operating conditions for the PCO process can increase the efficiency of the process and also operate the process more economically. Also, it is possible to scale up the process with more confidence by the kinetics modeling of the process and finding the rate constants. In this study, the effect of gas flow rate, light intensity, and VOC inlet concentration were investigated. The results show that the flow rate of 15 lit/min is more efficient, and the effect of the pollutant input concentration and light intensity directly affects the conversion percentage. The kinetic study of acetaldehyde removal was investigated in the fluidized bed reactor, and the best kinetic model was proposed based on reactor model regression on the outlet concentration data. The best model describes a langmuir-hynshelwood type model with adsorbed acetaldehyde's inhibition effect on the catalyst's surface. The R2 coefficient for the best kinetic type is 0.98. [Display omitted] • Designed the laboratory system for degradation of acetaldehyde. • Synthesized N–TiO 2 for acetaldehyde removal in visible light. • Design of experiment to find the effect of light intensity & initial concentration. • Use fluidized bed as a photoreactor for acetaldehyde degradation. • The kinetic study of acetaldehyde degradation. • Use genetic algorithm to found the kinetic constant. [ABSTRACT FROM AUTHOR]

The application of fungicide mixture is one of the most important measures to extend the service life of highly selective fungicides. Pyraclostrobin (PYR), which has been extensively used to control plant diseases by inhibiting mitochondrial respiration of pathogenic fungi, is at a high risk of resistance development. In this study, the potential of PYR alone or in combination with cystamine, an inhibitor of microbial transglutaminase, to suppress Fusarium graminearum was tested in vitro and in vivo. A synergistic effect of PYR/CYS mixture was observed both in vitro and when applied to etiolated wheat coleoptile. The control effect of PYR/CYS mixture on F. graminearum was better than that of PYR alone, which was reflected by the increased protection effect. The discrepancies of membrane permeability and the redox-physiological state were observed between PYR and PYR/CYS treatments, suggesting that an increased PYR availability in F. graminearum mycelia could be related with the observed synergistic action. Moreover, a synergistic profile was observed between PYR and CYS in regard of massive autophagosomes in mycelia, indicating that enhanced autophagy could be involved in the mode of action of PYR/CYS mixture. The differential content of mitochondrial metabolites between PYR and PYR/CYS treatments also provided evidence for CYS contribution to the fungicidal action of PYR/CYS mixture. The results provide insight into the synergistic mechanism of action of PYR/CYS mixture and an effective way to enhance the efficiency of PYR to combat F. graminearum. [Display omitted] • Cystamine (CYS) exhibits synergistic action with pyraclostrobin (PYR) against F. graminearum. • Autophagy and membrane permeability are involved in mode of action of PYR/CYS combination. • PYR/CYS combination induces severe mitochondrial dysfunctions in F. graminearum. • PYR/CYS combination provides a potential strategy by reducing PYR use to combat F. graminearum. [ABSTRACT FROM AUTHOR]

Background: Arsenic trioxide (As2O3), an ancient drug used in traditional Chinese medicine, has substantial anticancer activities, especially in the treatment of patients suffering from acute promyelocytic leukemia (APL); however the underlying mechanisms are not well understood. Methods: MTT assay was used to detect the cell viability. Flow Cytometry analysis and caspase-3 activity assay were used to measure apoptosis of APL cells. Caspase-3 and Bax levels were analyzed by western blot and let-7d and miR-766 levels were determined by real-time RT-PCR. Results: As2O3 significantly inhibited cell viability and induced apoptosis in APL cells. Several microRNAs, including let-7d and miR-766, were dysregulated in APL cells treated with As2O3. The expression of caspase-3 and Bax, which are targets of let-7d and miR-766, respectively, were up-regulated in As2O3 treated cells. Transfection of let-7d and miR-766 into NB4 cells decreased the expression of caspase-3 and Bax, respectively. Correspondingly, transfection of these microRNAs increased NB4 cell viability. As2O3 induced degradation of promyelocytic leukemia (PML), and then induced the down-regulation of both let-7d and miR-766 in NB4 cells. Conclusions: We construct a dysregulated microRNA network involved in As2O3-induced apoptosis in APL. Targeting this network may be a new strategy for the prevention of side effects associated with APL treatment with As2O3. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Superior response inhibition is an essential component of the advanced cognitive abilities of gifted children. This study investigated response inhibition in intellectually gifted children by recording event-related brain potentials (ERPs) during a Go/NoGo task. Fifteen intellectually gifted children and 15 intellectually average children participated. Our present findings showed that intellectually gifted children had shorter Go-P3 latency, indicating faster processing of Go stimuli, a finding consistent with previous studies. We focused on the two inhibition-related components, NoGo-N2 and NoGo-P3. The results showed that NoGo-P3 latency was shorter for intellectually gifted children compared to their average peers. N2 latency did not indicate the intelligence difference. These results suggested that intellectually gifted children showed faster inhibition when dealing with NoGo stimuli, and this superiority came from the later stages of inhibition, i.e., response evaluation or the success of inhibiting a response, as indexed by the shorter P3 latency. [Copyright &y& Elsevier]

Due to the heterogeneity of investor structure between the Chinese mainland stock market (A-share market) and the Hong Kong stock market (H-share market) as well as the limitations on arbitrage activities, most cross-listed stocks in the two markets (AH stocks) have the characteristics of "one asset, two prices", in which AH stocks with the same vote rights and dividend streams are traded at different prices in different markets. Based on the VAR (LA-VAR as well) model and a four-variable system including AH stock indices (AHXA, AHXH), the China Securities Index 300 (CSI 300), and the Hang Seng Index (HSI), this paper applies a new time-varying causality test to examine the causalities in prices and volatilities for two pairings (AXHA-AHXH pairing and CSI 300-HSI pairing) during the sample period spanning from 4 January 2010 to 21 May 2021. The empirical results exhibit statistically significant time-varying causalities of the two pairings. Specifically, at the price level, AHXH has a significant negative causal effect on AHXA from October 2017 to February 2020 except for several months in 2018, while AHXA merely has a negative impact on AHXA during a short period from March 2017 to May 2017. Of note, the direction of causalities in volatilities between AHXA and AHXH reverses. A positive causality is found from AHXA to AHXH at the 5% significance level during the period of April 2014 through May 2021, while no causality is detected in the opposite direction during the whole sample period. Meanwhile, the volatilities of CSI 300 significantly Granger cause those of HSI over the whole sample period, but not vice versa. Implications of our results are discussed. [ABSTRACT FROM AUTHOR]

Combined with the B-P (breakpoint) test and VAR–DCC–GARCH model, the relationship between WTI crude oil futures and S&P 500 index futures or CSI 300 index futures was investigated and compared. The results show that breakpoints exist in the relationship in the mean between WTI crude oil futures market and Chinese stock index futures market or US stock index futures market. The relationship in mean between WTI crude oil futures prices and S&P 500 stock index futures, or CSI 300 stock index futures is weakening. Meanwhile, there is a decreasing dynamic conditional correlation between the WTI crude oil futures market and Chinese stock index futures market or US stock index futures market after the breakpoint in the price series. The Chinese stock index futures are less affected by short-term fluctuations in crude oil futures returns than US stock index futures. [ABSTRACT FROM AUTHOR]

• Two optimized digestion method pyrohydrolysis & steam distillation were optimized. • These methods applied for extraction of halides from zinc and lead concentrate. • Extracts of two digestion methods analyzed by IC & comparison was drawn by t -test. • Both method allow analysis of F− & Cl− from complex sample with no matrix effect. • Very low LODs in the range of 0.0002–0.0011 mg/L were obtained for both halides. This study illustrates the feasibility of two digestion methods namely pyrohydrolysis (PH) and extended-steam distillation (E-SD) for the effective extraction of two halides (F− & Cl−) from six complex inorganic zinc and lead concentrate samples, followed by their determination with ion chromatography (IC). Although both digestion methods appeared feasible, but E-SD exhibited slightly better spiked-recovery values for both analytes at two concentration levels (0.25 mg/L, 0.50 mg/L). Various parameters of pH such as sample mass, temperature, flow rate of water vapor, concentration, and volume of absorption solution were optimized in order to achieve the optimum extraction recovery of both halides from six complex inorganic zinc and lead concentrate samples. Both methods exhibited satisfactory analytical figures of merit viz. excellent linearity with a determination coefficient (R2) greater than 0.9997, better LODs and LOQs (0.0002–0.0011 mg/kg), satisfactory recoveries (80.21–98.87%), negligible or no matrix effect (97.89%−104.45%), and intra- and inter-day precision values of less than 3.28%. Hence, both methods appeared feasible as no statistical discrepancies (p > 0.05) were observed among the obtained results except for few chlorides. Besides, the results of both methods were in good agreement with certified reference values of the "Zn-Australia" sample (ANOVA/ t -test, the confidence level of 95%). Thus proposed study provides two simple, efficient, and cost-effective choices for the sensitive and selective determination of both halides in complex inorganic samples. [ABSTRACT FROM AUTHOR]

• An enclosed steam distillation based extraction of F & Cl from copper concentrates. • An accurate and eco-friendly method is proposed for copper concentrates analysis. • Various parameters of steam distillation (SD) based extraction were optimized. • Better accuracy and precision of F & Cl obtained compared to conventional SD unit. This study illustrates the feasibility of comparative steam distillation based digestion of standard copper concentrate samples for the effective extraction of fluoride (F−) and chloride (Cl−) contents and their subsequent ion chromatographic determination. Digestion of copper concentrate samples for the extraction of halides was carried out with a miniaturized and modified enclosed steam distillation unit. It is comprised of only a pair of Teflon tubes placed on an enclosed and automatic heating set up for respective sample digestion and steam generation. A multi-hole silicon chip was used for the cooling of the steam tube carrying volatile analytes, and at the end, a receiving bottle having 10 mL of 0.1 M NaOH was placed for the absorption of extracted halide contents from copper concentrate sample. Finally, the extracted fluorides and chloride content in the absorption bottle were injected in a pre-running ion chromatography system. Both analytes were isocratically separated by pumping automatically generated 20 mM KOH as a mobile phase through a Thermo Fisher Scientific anion exchange column IonPac® AS15 (250 mm × 4 mm i.d; 9 µm particle size) that further protected with a guard IonPac® AS15 (50 mm × 4 mm i.d; 9 µm particle size). The developed method showed good linearity for both halides in the range of 0.0020–5 µg/mL with an excellent correlation coefficient (0.99952). The limits of detection (LODs) of F− and Cl− were 0.0002 and 0.0005 µg/mL, respectively. Besides, the method showed excellent accuracy (87.95–100.02%) along with intra-and-inter-day precision of less than RSDs ≤ 1.41%. The developed method appeared robust and showed no matrix interference at analyte peaks of interest. Finally, this miniaturized and modified enclosed steam digestion unit compared with a conventional steam distillation unit. It appeared safer, reproducible, miniaturized (save reagents) and tap water free setup for the effective extraction of both halides from four complex inorganic copper concentrate samples. [ABSTRACT FROM AUTHOR]

Our previous research found that Sangguayin (SGY) deccoction made by four dietary and medicinal plant components (Leaf of Morus alba L., Root of Pueraria lobata (Willd.) Ohwi., Root of Dioscorea opposita Thunb. and Fruit of Momordica charantia L.) showed significant anti-diabetic effects on db/db mice and high fat diet induced obese mice. Nevertheless, it remained unclear what the role of gut microbiota in the hypoglycaemia effects of SGY. This study aimed to examine the beneficial effects of Sangguayin Deccoction against metabolic syndrome and and its regulating role in gut microbiota and hepatic metabolome. C57BL/6J mice were divided to a normal chow diet (NCD), high-fat diet (HFD), and high-fat diet with Sangguayin Decoction (HFD-SGY, oral dose of 250 mg/kg/d) for 16 weeks. Next generation sequencing was applied for analyzing the gut microbial community of colonic contents. Further, untargeted metabolomic analysis based on LC-MS was used for determining the changes of hepatic metabolites. Hepatic genes expression were measured by quantitative PCR. SGY supplement decreased blood glucose level and glucose intolerance. Illumina MiSeq sequencing revealed that SGY increased Verrucomicrobia phylum, resulting in a bloom of Akkermansia , and eventually upregulated the contents of Lachoclostridium and Roseburia. Additionally, dietary SGY decreased bacteria including Faecalibaculum , and Blautia. Moreover, the hepatic lipid metabolism was notably altered by SGY treatment. The oxidation of glutamione metabolism idecreasees, production of poly-unsaturated fatty acid (PUFA) got significant increase in liver tissue. The reversion of PUFA metabolism by SGY may act through PPARα mediated Fads1 and Fads2 gene expression. The altered metabolites in liver showed intimate correlatship with modified genera. Data indicated that SGY reshaped gut microbial structure and improved PUFA metabolism. These functions of SGY may alter hepatic lipid metabolism, conferring preventative effects against high-fat diet induced metabolic syndrome. Image 1 [ABSTRACT FROM AUTHOR]

Analysis of acidic pharmaceuticals in complex biological samples is a challenging and formidable task due to the existence of interfering constituents within the sample matrices. Therefore, in order to avoid analytical column clogging and suppression/enhancement of signals of the analyte of interest, herein a simple, cost-effective and quick online ion chromatography based clean-up setup was introduced. This system was further coupled with a cost-effective homemade photochemically induced fluorimetric (PIF) setup for direct online conversion of non-fluorescent acidic pharmaceutical drugs into their respective fluorescent species. This advantageous system was favorably applied for the determination of four non-fluorescent acidic compounds in two complex biological samples (human serum and oral fluid) with minimum labor and organic solvent consumption. At optimized conditions, the developed method has shown good sensitivity, selectivity, satisfactory recoveries (88.68–102.14%) and low limits of detection (0.35–8.10 μg/L) with minimum or zero matrix effect. • An online SPE-IC system was designed for analysis of non-fluorescent acidic drugs. • Online clean-up setup was used for matrix removal from biological samples. • A post-column UV induced photochemical reactor was also fabricated with the IC system. • All drugs were isocratically separated and detected with a fluorescent detector. • Validated results were acceptable for all drugs in two complex biological samples. [ABSTRACT FROM AUTHOR]