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A nanoflower-like bimetallic FeP/CoP-1-350 heterostructure electrocatalyst with rich interfaces shows excellent OER electrocatalytic activity.

A 3D hierarchical multifunctional tubular magnetomotor with intrinsic peroxidase-like activity was designed and constructed for the active detection and specific capture of glyphosate from wastewater at neutral pH.

Herein, we first report a biomass route to synthesize 3D, hierarchical, ACFs (active carbon fibers)-based micromotors with superior photo-Fenton-like catalytic activity. As a biomass with unique fiber morphology, cotton fibers are abounded and inexpensive, inspiring us to explore bubble generated ACFs-based micromotors. Mn3O4 nanosheets coated ZnO nanorods are decorated on the surface of ACFs, each component of micromotor providing different functionalities. ACFs can be an electron transfer mediator to facilitate the formation of •OH radicals, adsorbent to condense organic pollutant on the surface of micromotor and support for the high dispersion of Mn3O4@ZnO heterojunction, facilitating the light harvesting and providing more active site. Mn3O4 act as Fenton-like catalyst and the engine for self-propulsion. The speed of this Pt-free micromotors could reach 198 μms−1 in a 7% H2O2 solution. It is demonstrated that fluid mixing induced by the autonomous motion significantly increases the chance of contact between reactive oxygen species and pollutant molecules and thus enhances the degradation rate of pollutant, which was 3.5 times than nonproprelling counterparts. This novel ACFs-based micromotor provides new insights into the design features of micro/nanomotors for water treatment.

The study of screening active constituents from traditional Chinese medicine (TCM) is important for explicating the mechanism of action of TCM and further evaluating the safety and efficacy effectively. However, detecting and identifying the active constituents from complicated biological samples still remain a challenge. Here, a practical, quick, and novel integrated strategy from in vitro, in situ, in vivo to in silico for rapidly screening the active constituents was developed. Firstly, the chemical profile of TCM in vitro was identified using UPLC-Q Exactive-Orbitrap HRMS. Secondly, the in situ intestinal perfusion with venous sampling (IPVS) method was used to investigate the intestinal absorption components. Thirdly, after intragastric administration of the TCM extract, the in vivo absorbed prototype components were detected and identified. Finally, the target network pharmacology approach was applied to explore the potential targets and possible mechanisms of the absorbed components from TCM. The reliability and availability of this approach was demonstrated using Tongfengding capsule (TFDC) as an example of herbal medicine. A total of 141 compounds were detected and identified in TFDC, and among them, 64 components were absorbed into the plasma. Then, a total of 35 absorbed bioactive components and 50 related targets shared commonly by compounds and gout were integrated via target network pharmacology analysis. Ultimately, the effects of the absorbed components on metabolism pathways were verified by experiments. These results demonstrated that this original method may provide a practical tool for screening bioactive compounds from TCM treating particular diseases. Furthermore, it also can clarify the potential mechanism of action of TCM and rationalize the application of TFDC as an effective herbal therapy for gout.

We aimed to develop a physiological-based pharmacokinetic and dipepidyl peptidase 4 (DPP-4) occupancy model (PBPK-DO) characterized by two simultaneous simulations to predict pharmacokinetic (PK) and pharmacodynamic changes of saxagliptin and metabolite M2 in humans when coadministered with CYP3A4 inhibitors or inducers. Ketoconazole, delavirdine, and rifampicin were selected as a CYP3A4 competitive inhibitor, a time-dependent inhibitor, and an inducer, respectively. Here, we have successfully simulated PK profiles and DPP-4 occupancy profiles of saxagliptin in humans using the PBPK-DO model. Additionally, under the circumstance of actually measured values, predicted results were good and in line with observations, and all fold errors were below 2. The prediction results demonstrated that the oral dose of saxagliptin should be reduced to 2.5 mg when coadministrated with ketoconazole. The predictions also showed that although PK profiles of saxagliptin showed significant changes with delavirdine (AUC 1.5-fold increase) or rifampicin (AUC: a decrease to 0.19-fold) compared to those without inhibitors or inducers, occupancies of DPP-4 by saxagliptin were nearly unchanged, that is, the administration dose of saxagliptin need not adjust when there is coadministration with delavirdine or rifampicin.

The study of screening active constituents from traditional Chinese medicine (TCM) is important for explicating the mechanism of action of TCM and further evaluating the safety and efficacy effectively. However, detecting and identifying the active constituents from complicated biological samples still remain a challenge. Here, a practical, quick, and novel integrated strategy from in vitro, in situ, in vivo to in silico for rapidly screening the active constituents was developed. Firstly, the chemical profile of TCM in vitro was identified using UPLC-Q Exactive-Orbitrap HRMS. Secondly, the in situ intestinal perfusion with venous sampling (IPVS) method was used to investigate the intestinal absorption components. Thirdly, after intragastric administration of the TCM extract, the in vivo absorbed prototype components were detected and identified. Finally, the target network pharmacology approach was applied to explore the potential targets and possible mechanisms of the absorbed components from TCM. The reliability and availability of this approach was demonstrated using Tongfengding capsule (TFDC) as an example of herbal medicine. A total of 141 compounds were detected and identified in TFDC, and among them, 64 components were absorbed into the plasma. Then, a total of 35 absorbed bioactive components and 50 related targets shared commonly by compounds and gout were integrated via target network pharmacology analysis. Ultimately, the effects of the absorbed components on metabolism pathways were verified by experiments. These results demonstrated that this original method may provide a practical tool for screening bioactive compounds from TCM treating particular diseases. Furthermore, it also can clarify the potential mechanism of action of TCM and rationalize the application of TFDC as an effective herbal therapy for gout.

Self-propelled micro/nanomotors attract a great deal of attention from the scientific community due to their great potential in environmental and biomedical applications. Here, molecularly imprinted magnetic micromotors with highly selective recognition and capture for antibiotics are presented. Such micromotors, powered by local fuel and with precise trajectory control over the self-propulsion direction, exhibit a unique 3D hierarchical tubular structure constructed by a combination of the biomass route and atom transfer radical polymerization (ATRP). Each component of such a hierarchical structure performs its own function: Br–MgAl layered double hydroxide (LDH) nanosheets as the initiator for ATRP to selectively recognize target molecules, Mn3O4 nanoparticles as the catalyst for H2O2 decomposition to generate oxygen bubbles for self-propulsion, and Fe3O4 nanoparticles as the magnetic component for magnetic orientation and recycling. Due to the synergetic effects of self-propelled movement and highly exposed selective recognition sites from molecularly imprinted LDH nanosheets, such micromotors can rapidly recognize, capture and remove target antibiotics from water. The maximum doxycycline (DC) adsorption capacity of micromotors is up to 224.2 mg g−1 in the presence of 2% H2O2, which is 1.6 times greater than their non-micromotor counterparts. More importantly, these micromotors can be quickly recycled by magnetic separation. This study provides a new insight for designing novel molecularly imprinted micromotors for water treatment.

Self-propelled micro- and nanomotors are a current research focus and have shown attractive potential in environmental applications. Here, we report a biomass approach to construct a novel tubular micromotor decorated with a nanozyme/natural enzyme hybrid, which integrated the advantages of the self-propelled movement, selectivity of a natural enzyme and catalytic activity of artificial nanozymes. Such a micromotor had a unique hierarchical structure where laccase immobilized-Fe-BTC MOF nanoparticles grew uniformly on Mn2O3–NiFe2O4 nanosheets, which was constructed using natural kapok fiber as a template. This laccase-integrated Fe-BTC/NiFe2O4 micromotor was capable of self-propulsion with a speed of 120 μm s−1 by oxygen bubbles via the decomposition of H2O2 catalyzed by Mn2O3. Owing to the incorporation of autonomous motion with high selectivity of natural laccase and high peroxidase-like activity of the Fe-BTC/NiFe2O4 nanozyme, these micromotors exhibited much higher catalytic activity to methylene blue degradation than their passive counterparts. Besides as a substrate to accommodate laccase immobilized-Fe-BTC, magnetic NiFe2O4 also enabled the remote magnetic control on the movement direction.

Screening functional food ingredients (FFI) from medicinal and edible plants (MEP) has still remained a great challenge due to the complexity of MEP and its obscure function mechanisms. Herein, an integrated strategy based on sequential metabolites identification approach, network pharmacology, molecular docking, and surface plasmon resonance (SPR) analysis was proposed for quickly identifying the active constituents in MEP. First, the sequential biotransformation process of MEP, including intestinal absorption and metabolism, and hepatic metabolism, was investigated by oral gavage, and intestinal perfusion with venous sampling method. Then the blood samples were analyzed by UPLC-Q Exactive Orbitrap HRMS. Second, the network pharmacology approach was used to explore the potential targets and possible mechanisms of the in vivo metabolites of MEP. Third, molecular docking and SPR approaches were used to verify the specific interactions between protein targets and representative ingredients. The proposed integrated strategy was successfully used to explore the heptoprotective components and the underlying molecular mechanism of Paeoniae Radix Alba (PRA). A total of 44 compounds were identified in blood samples, including 17 porotypes and 27 metabolites. The associated metabolic pathways were oxidation, methylation, sulfation, and glucuronidation. After further screening, 31 bioactive candidates and 377 related targets were obtained. In addition, the bioactive components contained in PRA may have therapeutic potentials for non-alcoholic fatty liver disease (NAFLD). The above results demonstrated the proposed strategy may provide a feasible tool for screening FFI and elaborating the complex function mechanisms of MEP.

Despite the increasing knowledge of biological isotope effect, comprehensive understanding of heavy isotope effect in the biological contexts has remained far less than expectation. The present study investigated the carbon isotope effect of 13C enriched testosterone on human cells. It was among the rare studies on carbon isotope effect of bioactive compound. Human osteoblasts, human aortic endothelial cells, and human umbilical vein endothelial cells were cultured in vitro and treated with testosterone and 13C enriched testosterone (13C/12C:6.7%). The impacts of physiological to pharmacological concentrations (10-10-10-5mol/L) of the bioactive compound were taken into account. The cell proliferation activities were measured using MTS assay. The levels of alkaline phosphatase and osteocalcin in osteoblasts were tested. Our results established that 13C enriched testosterone exhibited different biological effects from testosterone. At the concentrations of 10-10mol/L and 10-5mol/L, there were significant differences in prompting cell proliferation between testosterone and 13C enriched testosterone. At physiological concentrations, testosterone prompted proliferations of the three kinds of cells; whereas, 13C enriched testosterone did not prompt the cell proliferation, and its effects were not concentration dependent. At supraphysiological concentration (10-5mol/L), testosterone had the trend of inhibiting cell growth; whereas, 13C enriched testosterone had the trend of prompting cell growth. 13C enriched testosterone significantly enhanced osteocalcin secretion in human osteoblasts at supraphysiological concentration. These findings challenged the common view of growth retardation effect of heavy isotope, which imply that biological isotope effects are worthy of further study. The potential applications of 13C enriched compound were discussed.

This paper reports a novel bioinspired Pt-free three-dimensional (3D) EDTA (Ethylene Diamine Tetraacetic Acid)-functionalized Eu-MOF (Metal Organic Framework)-based fluorescent micromotor as an active self-propelled micromachine for detection, capturing, and removal of Fe3+ from water. This micromotor was composed of EDTA-NiAl-CLDHs (calcined layered double hydroxides)/MnO2 and a Eu-MOF, with each component functioning differently. The outer fluorescent Eu-MOF layer acted as a fluorescent sensor for detecting Fe3+, while the inner EDTA-functionalized NiAl-CLDH/MnO2 layer functioned as a functional unit for Fe3+ adsorption, as well as the buffer layer for the nucleation and growth of the Eu-MOF. MnO2 served as a catalyst in decomposing H2O2 for self-propulsion of the micromotor. The obtained micromotor exhibited a circle motion form with an average speed of 56.9 μm s−1 in 5 wt% H2O2. This EDTA-functionalized Eu-MOF-based fluorescent micromotor showed excellent selectivity, high sensitivity (Stern–Volmer constant Ksv = 1.3 × 104 L mol−1, and limit of detection LOD = 0.15 μM) and high adsorption capacity (the maximum equilibrium adsorption capacity qmax = 112 mg g−1) for Fe3+. Therefore, the novel 3D bifunctional fluorescent micromotor combining the MOF, EDTA-functionalized CLDHs and autonomous motion is promising for the simultaneous detection/adsorption and removal of pollutants, expanding the potential resources for micromotors and providing an efficient option for water quality monitoring and wastewater treatment.

This paper applies sequence alignment method of bioinformatics to financial analysis to find hidden pattern from financial markets. Results of simulation suggest that sequence alignment method can be used to identify key points to inset, delete and replace data in time series, to find lead-lag relationship between two time series, and to analyze matching patterns. We further propose a new score matrix named similarity-oriented matrix which is designed based on the characteristics of financial time series, and apply it to China’s stock market. The empirical analysis verifies the validity of our proposed score matrix, and tests the sensitivity for different threshold values of symbols definition.

Artificial self-propelled micro/nano-motors have emerged as a promising hot spot in the fields of water-body remediation and environmental protection. Herein, we report a novel multifunctional micromotors with dual enzyme-like activities for simultaneous colorimetric determination and removal of environmental contaminants. Thanks to the tubular morphology inherited from kapok fibers, these bovine serum albumin-functionalized NiCo2O4@MnO2/C (BSA-NiCo2O4@MnO2/C) micromotors with dual oxidase/peroxidase-like activity can move forward quickly in aqueous solutions via a bubble recoil mechanism, which can not only enhance the colorimetric sensing performance, but also improve the removal efficiency toward Cu2+ ion by enhancing the mass transfer both in the detection and catalytic degradation systems. Moreover, the unique 3D hierarchical architecture assembled by core-shell NiCo2O4 @MnO2 nanosheets and C microtubes can provide more accessible reactive sites and thus dramatically facilitate such detection process. In combination with the autonomous motility, intrinsic oxidase/peroxidase-like activities and precisely tuned hierarchical architecture, these automatic micromachines not only are able to detect Cu2+ selectively and sensitively with the limit of detection of 2.0 nM, but also quickly remove Cu2+ from wastewater with maximal adsorption capacity of 161.8 mg g−1. Furthermore, these micromotors exhibit excellent catalytic activity for the degradation of tetracycline hydrochloride. This multifunctional mobile platform will provide a new and promising strategy for the simultaneous detection and decontamination of poisonous metal ions and other pollutants in aqueous samples.

Musk, the dried secretion of the musk pod (sac) of adult male musk deer, has been used as traditional Chinese Medicine (TCM) in China and south-east Asian countries for thousands of years. Due to the anabolic steroid component in this TCM, musk preparations have been included in the list of medical products containing prohibited substances employed for doping by the State Food and Drug Administration of China. The application of musk pod formulation was claimed to be responsible for some adverse analytical findings (AAFs) in the 2011 FIFA Women's World Cup. Our preliminary study has suggested that musk ingestion did not lead to AAFs of doping control with the single dosage of 100 mg. However, the influences of musk administration in large and multi dosage are still unclear. The aim of this study is to further investigate the influences of musk administration for doping control. Wild and domestic deer musk samples were collected. The concentrations and δ13 C-values of steroids in musk were analyzed. In an excretion study, 200 and 100 mg of wild and domestic deer musk samples were administrated by 29 subjects, respectively. Fluctuations in steroid profile could be observed, and the ratio of 5α-androstane-3α,17β-diol to 5β-androstane-3α,17β-diol was more sensitive than other parameters. In the IRMS test, the ∆Δδ13 C-value between endogenous reference compound and etiocholanolone was a sensitive parameter, and AAFs were obtained. It is the first time to confirm with excretion study that musk administration could lead to positive result of doping control. Copyright © 2017 John Wiley & Sons, Ltd.

A novel core-shell Fe

This paper reports the first proof-of-concept of using bioinspired ZIF-8 based micromotors for efficient water remediation. Natural kapok fibers have unique hollow structure that contains cellulose and lignin, inspiring the design and fabrication of bubble-driving tubular micromotors as an active self-propelled micromachine for the removal of organic pollutants from water. The outer dense ZIF-8 layer can adsorb organic pollutants on the micromotors, and the inner catalyst acts as the engine decomposing fuel H2O2 for providing bubble propulsion. The magnetic γ-Fe2O3 enables the external magnetic control movement and recovery of micromotors. The maximum adsorption capacity of ZIF-8-based magnetic micromotors toward Congo red and doxycycline were high as 394 and 242 mg g−1, respectively, mainly due to the enhanced micromotor-pollutant contacts by their autonomous motion and the resulting mixing associated effect. This novel ZIF-8 micromotor also showed outstanding stability and reusability in aqueous solution, indicating that their great potential for future application in water treatment.

Biotemplating method is a promising way to obtain hierarchical materials with unique morphology and property. In the current work, a novel hierarchically porous ZnAl-CLDH (calcined layered double hydroxides)/FeWO4 had been successfully synthesized by a facile biotemplated method. The obtained samples were characterized in detail via FESEM-EDX, TEM, XRD, IR, TGA, and BET techniques. The as-synthesized ZnAl-CLDH/FeWO4 hierarchical microspheres were composed of ZnAl-CLDH nanosheets and FeWO4 nanoparticles. The obtained sample exhibited both high adsorption and visible-light photocatalytic activity toward Congo Red (CR) in water. It was found that the adsorption process was well described by the pseudo-second-order kinetic model and the Langmuir isotherm model, while the photocatalytic degradation process was well fitted to the first-order kinetics model. The enhanced photocatalytic performance was mainly due to the hierarchically porous structure that could offer more exposed active sites, as well as the unique energy band structure of heterostructures, that facilitated the efficient separation and transfer of photoinduced carriers and enhanced light harvesting. In addition, the as-prepared sample had quickly magnetic response and could be easily separated from water under an external magnetic field after wastewater treatment.

The accurate quantitative determination of affinity and binding kinetics (BK) for tight binding inhibition is extraordinary important from both the continuous optimization of compounds, particularly in developing structure–activity relationships (SAR), and the prediction of in vivo target occupancy (TO). Due to the unique properties for tight binding inhibition that the inhibitors are characterized by the ultrahigh-affinity, relatively fast association to the target enzyme combined with extremely slow dissociation of the inhibitor-enzyme binary complex, the classical steady state equilibrium methods are no longer valid. Here, we made several recommendations of how to design the optimal experiments and apply special mathematical calculation approaches to quantitatively evaluate the accurate affinity and BK as the examples of two tight binding inhibitors against the xanthine oxidase (XO), as well as compared the differences in the results calculated from the different data analytical methods and analyzed the influence of these differences on the XO engagement in human. Analysis of the results displayed that the accurate apparent dissociation constant (Ki*, app) was 0.2 ± 0.06 nM for topiroxotstat and was 0.45 ± 0.2 nM for febuxostat; that on-rate (kon) was (4.3 ± 1.1) × 106 M−1s−1 for topiroxotstat and was(133.3 ± 3.5) × 106 M−1s−1 for febuxostat, and off-rate (koff) was (1.0 ± 0.2) × 10−5 s−1 for topiroxotstat and was ≤ 0.16 × 10−5 s−1for febuxostat. Moreover, there were significant differences in the Ki*, app and koff values estimated using the appropriate specialized methods for tight binding inhibition versus classical steady state equilibrium methods, with the substantial differences of 14-fold and 32-fold reduction for topiroxostat, respectively, and of 9.6-fold and ≥ 213-fold reduction for febuxostat, while the kon values remain the moderate differences for the two inhibitors. The obvious greater AUC of XO engagement time courses and longer durations of above 70% engagement by the appropriate specialized methods for tight binding inhibition were observed that the results display the differences of 70.1% and 88%, respectively for topiroxostat and of 38.1% and 35.0%, respectively for febuxostat in human liver cell than by classical steady state equilibrium methods. Again, our studies provide several valuable recommendations of the optimal experiment protocols and appropriate analytical approaches for accurately quantitatively assessing the affinity and BK parameters as well as demonstrate the ability of our recommended methods to generate reliable data for tight binding inhibitors against XO.

A novel core-shell Fe3O4/CoFe-LDH (layered double hydroxides) hybrid as a peroxidase mimic for the colorimetric detection of ascorbic acid was first fabricated via a facile two-step route. The resulting Fe3O4/CoFe-LDH hybrid exhibited much higher peroxidase-like catalytic activity for the oxidation of 3,3′,5,5′- tetramethylbenzidine (TMB) with H2O2 than the pristine Fe3O4 and CoFe-LDH nanosheets owing to the unique hierarchical architecture containing more exposed active sites and the synergistic effect between Fe3O4 and CoFe-LDH. A sensitively and selectively visual sensor for the determination of ascorbic acid (AA) was successfully constructed based on the reduction effect of AA with enediol group on the formed oxidation of TMB, which exhibited a sensitive response to AA in the range of 0.5 ∼ 10 μM with the detection limit of 0.2 μM. Additionally, the Fe3O4/CoFe-LDH magnetic hybrid could be easily recycled by applying a magnetic field. This work provided a feasible means for the fabrication of magnetic nanomaterials with encouraging prospect in biosensing, environmental monitoring and medical diagnostics.

The development of new nanomaterials for the highly efficient wastewater treatment has been one of the hot scientific researches. Herein, we report a novel 3D Fe3+-doped BiOBr-based magnetic Janus micromotors with superior solar photo-Fenton catalytic activity for organic pollutant degradation. Taking advantage of hydrogen peroxide as reagent and fuel, Fe3+-doped BiOBr based Janus micromotors exhibited extremely high efficiency for methylene blue degradation in a solar photo-Fenton system even at mild pH conditions, which was almost 4 times than BiOBr. The speed of the Janus micromotors could reach 214.7 ± 19.4 μm s−1 in a 5% H2O2 solution. Factors influencing the solar photo-Fenton reaction including Fe3+-doping amount, pH, concentration of H2O2, self-propelled movement as well as mechanical stirring were investigated to clarify the degradation mechanism. Nearly 97% of methylene blue was degraded by Fe0.11Bi0.89OBr/Fe3O4/Mn3O4 Janus micromotors in the presence of 3% H2O2 solution at neutral environment within 50 min. This study provided a new insight into the preparation of Janus micromotors for water purification applications based on solar photo-Fenton reaction.

Ezetimibe is a novel lipid-lowering agent that inhibits intestinal absorption of dietary and biliary cholesterol. In the present work, a simple, sensitive and reproducible gradient reverse phase high performance liquid chromatographic (RP-HPLC) method for separation and determination of the related substances of ezetimibe was developed and validated. Eleven potential process-related impurities (starting materials, (3S,4S,3'S)-isomer, degradants and byproducts) were identified in the crude samples. Tentative structures for all the impurities were assigned primarily based on comparison of their retention time and mass spectrometric data with that of available standards and references. This method can be applied to routine analysis in quality control of both bulk drugs and commercial tablets. Separation of all these compounds was performed on a Phenomenex Luna Phenyl-Hexyl (100mm×4.6mm, 5μm) analytical column. The mobile phase-A consists of acetonitrile-water (pH adjusted to 4.0 with phosphoric acid)-methanol at 15:75:10 (v/v/v), and mobile phase-B contains acetonitrile. The eluted compounds were monitored at 210nm. Ezetimibe was subjected to hydrolytic, acid, base, oxidative, photolytic and thermal stress conditions as per ICH serves to generate degradation products that can be used as a worst case to assess the analytical method performance. The drug showed extensive degradation in thermal, acid, oxidative, base and hydrolytic stress conditions, while it was stable to photolytic degradation conditions. The main degradation product formed under thermal, acid, oxidative, base and hydrolytic stress conditions corresponding to (2R,3R,6S)-N, 6-bis(4-fluorophenyl)-2-(4-hydroxyphenyl)-oxane-3-carboxamide (Ezetimibe tetrahydropyran impurity) was characterized by LC-MS/MS analysis. The degradation products were well resolved from the main peak and its impurities, thus proved the stability-indicating power of the method. The developed method was validated as per international conference on harmonization (ICH) guidelines with respect to specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, precision and robustness.

Biomass-derived hierarchically porous CoFe-LDH (layered double hydroxides)/CeO2 hybrid possessing an inherent peroxidase-like activity was first fabricated employing kapok as bio-template. The CeO2 fibers not only exhibited peroxidase-like activity, but also served as a support and guided the deposition of CoFe-LDH nanosheets on their surface to form a hierarchically porous network. The resultant CoFe-LDH/CeO2 hybrid acted as a peroxidase mimic to catalyze 3,3′,5,5′- tetramethylbenzidine (TMB) with H2O2 to generate a typical blue colored product. Furthermore, CoFe-LDH/CeO2 hybrid displayed superior peroxidase-like catalytic property compared to the pristineCeO2 and CoFe-LDH, which was attributed to the presence of more effective active sites of unique hierarchical-porous architecture and the synergistic effect between CoFe-LDH and CeO2. A facile and sensitive sensing system for H2O2 and glucose determination was successfully proposed, which exhibited a sensitive response to glucose ranging from 0.05–2 mM with a detection limit of 0.015 mM based on the accelerated electron transfer between TMB and H2O2 with the assistance of CoFe-LDH/CeO2. This paper offered a feasible way or the fabrication of materials with hierarchical structure and provided a new insight into seeking novel peroxidase mimics with boosted catalytic activities.

Progesterone (PROG) is a naturally occurring progestagen, which has been used to prevent preterm birth, control persistent anovulatory bleeding, and treat premenstrual syndrome in clinical practices. Studies on the metabolism of PROG have demonstrated that PROG is the precursor of other steroids such as 5β-pregnane-3α,20α-diol (PD), testosterone (T), and 17-hydroxyprogesterone. PD is the most commonly used endogenous reference compound (ERC) in the isotope ratio mass spectrometry (IRMS) analysis for doping control. It is expected that the PROG administration could affect the carbon isotope ratios ((13)C/(12)C, expressed as δ (13)C-value) of PD and T metabolites, and lead to the false-negative or false-positive results in doping test. The influences of oral and intramuscular administration of PROG on the urinary steroid profile and carbon isotope ratios of steroids were investigated in this study. It was demonstrated that the urine concentrations and the δ (13)C-values of PD were affected obviously. The depleted δ (13)C-values of PD could be used to suggest PROG administration. Using PD as ERC may result in the distorted evaluation for suspicious urine sample in IRMS analysis when PROG is ingested. The 5α-androst-16-en-3α-ol and 11β-hydroxyandrosterone could be used as the alternative ERCs in case of PROG administration. The carbon isotope ratios of androsterone (An) and etiocholanolone (Etio), two T metabolites, remained unchanged throughout the excretion study, which suggested that the δ values of An and Etio could still be used as the urinary markers of T administration even when PROG was administrated.

Novel hierarchically porous CoAl-LDH (layered double hydroxides)/MFe2O4(Ni, Zn, Co) hybrids with excellent peroxidase-like catalytic activity, high selectivity and reusability were first fabricated by using natural cotton as a bio-template. Among them, CoAl-LDH/NiFe2O4 exhibited the best intrinsic peroxidase-like property due to its 3D hierarchically porous structure with more exposed active sites, which could effectively catalyze peroxidase substrate 3,3′,5,5′- tetramethylbenzidine (TMB) in the presence of H2O2 to produce typical blue color reaction. A facile and visual system for glucose detection using glucose oxidase was successfully established, which exhibited a sensitive response to glucose in the range of 25–400 μM with detection limit of 13 μM based on the hydroxyl radical originated from the decomposition of H2O2 by the catalysis of CoAl-LDH/MFe2O4(Ni, Co, Zn) hybrids. This work offered an effective strategy to achieve morphology-controllable hierarchically porous materials and provided a new insight into seeking novel enzyme mimetics with enhanced catalytic activities.

As the market develops, the characteristics and patterns of China’s stock market have changed greatly. Likewise, the performance of different types of stocks has varied widely. In order to distinguish one type of stock from another, stocks are classified into sectors by region, country, style, industry, and so on. This chapter studies how the stock market works and changes at the meso-level from the perspective of style and sector. It then observes the development of the entire stock market. The first part examines the conditions and performances of typical large-cap, mid-cap and small-cap stocks, growth stocks and value stocks according to their styles, and explores the characteristics of investor behavior. The second part studies the past and present of representative sectors, as well as the opportunities and challenges they face, according to their industries, to provide further clues for decision-making. The third part, based on the previous analysis, improves the existing schemes for selecting stocks and optimizes sector indices to enable passive investors to make more informed decisions.

Isotope ratio mass spectrometry (IRMS) is applied to confirm testosterone (T) abuse by determining the carbon isotope ratios ( δ 13 C value). However, 13 C labeled standards can be used to control the δ 13 C value and produce manipulated T which cannot be detected by the current method. A method was explored to remove the 13 C labeled atom at C-3 from the molecule of androsterone (Andro), the metabolite of T in urine, to produce the resultant (A-nor-5α-androstane-2,17-dione, ANAD). The difference in δ 13 C values between Andro and ANAD (Δ δ 13 C Andro–ANAD , ‰) would change significantly in case manipulated T is abused. Twenty-one volunteers administered T manipulated with different 13 C labeled standards. The collected urine samples were analyzed with the established method, and the maximum value of Δ δ 13 C Andro–ANAD post ingestion ranged from 3.0‰ to 8.8‰. Based on the population reference, the cut-off value of Δ δ 13 C Andro–ANAD for positive result was suggested as 1.2‰. The developed method could be used to detect T manipulated with 3- 13 C labeled standards.