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Ionic liquid (IL)-modified UiO-66-NH2 composite was prepared and used as sorbent of dispersed solid-phase extraction (dSPE) for extracting trace benzoylurea insecticides (BUs) from complex environmental matrices. The IL in framework endowed the prepared material had electropositive characteristics, which can produce interaction with electron rich guest molecules, such as BUs. The high thermal and chemical stability of UiO-66-NH2/IL enabled it to be reused for 16 times without significant reduction in adsorption performance. Due to the multiple forces including π-π, hydrogen bonding, and fluorine-fluorine interaction, UiO-66-NH2/IL showed good adsorption performance, short adsorption time (20 s) and rapid desorption ability (60 s) for BUs. Under the optimal conditions, the method exhibited wide linear range (0.02–500 ng mL-1) with correlation coefficient (R2) not worse than 0.9928, high enrichment factor (252–300), and low detection limit (0.005–0.4 ng mL-1). The dispersed solid phase extraction coupling with high-performance liquid chromatography-diode array detector (dSPE-HPLC-DAD) was successfully used to detection of BUs in real environmental samples and satisfactory recoveries were obtained (80.5%±2.4–118%±3.2). The results indicated that UiO-66-NH2/IL composite can be a potential sorbent for the preconcentration of trace insecticides in environmental samples. [ABSTRACT FROM AUTHOR]

Based on multiple ligands strategy, a series of multivariate metal organic frameworks (MTV-MOFs) named as PCN-224-DCDPS x were prepared using one-pot solvothermal method to extract and remove sulfonamide antibiotics (SAs). The pore structure and adsorption performance can be further regulated by modulating the doping ratios of medium-tetra(4-carboxylphenyl) porphyrin and 4,4′-dicarboxydiphenyl sulfones. The MTV-MOFs of PCN-224-DCDPS 1.0 possesses very large specific surface area (1625 m2/g). Using PCN-224-DCDPS 1.0 as sorbent, a dispersive solid-phase extraction method was developed to extract and preconcentrate SAs from water, eggs, and milk prior to high performance liquid chromatography analysis. The limits of detection of method were determined between 0.17 and 0.27 ng/mL with enrichment factors ranging 214–327. The adsorption can be finished within 30 s, and the recovery rate remains above 80 % after 10 repeated uses. The adsorption capacities of sorbent were determined from 300 to 621 mg/g for sulfadiazine, sulphapyridine, sulfamethoxydiazine, sulfachlorpyridazine, sulfabenzamide, and sulfadimethoxine. The adsorption mechanisms were investigated and can be attributed to π-π interactions, hydrogen bonds, and electrostatic interactions. This work represents a method for preparation of MTV-MOFs and uses as sorbent for extraction and enrichment of trace pollutants from complex samples. [Display omitted] • Zr-based multivariate MOF (PCN-224-DCDPS 1.0) was prepared by multiple ligands strategy. • PCN-224-DCDPS 1.0 was used as sorbent for adsorption of sulfonamide antibiotics (SAs). • The sorbent has excellent crystal structure stability and adsorption performance. • The adsorption of SAs with PCN-224-DCDPS 1.0 can be finished within 30 s. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zr-based MOF-on-MOF composite synthesized by seed epitaxial growth method. • PCN-222@PCN-134 as sorbent to extract and enrich trace sulfonamides (SAs). • LODs of dSPE-HPLC-DAD with PCN-222@PCN-134 as sorbent ranging 0.03–0.27 ng/mL. • Enrichment factors and recoveries were achieved at 254–333 and 76.4–120.1% • Excellent adsorption capacity was attributed to synergistic effect between MOFs. A MOF-on-MOF composite (PCN-222@PCN-134) was synthesized by seed epitaxial growth method and applied as sorbent to extract sulfonamides (SAs) in different sample matrices. Using PCN-222@PCN-134 as sorbent, a dispersive solid-phase extraction was developed to clean-up and preconcentration of SAs prior to HPLC-DAD analysis. The linear range of the method are achieved between 0.1 and 200 ng/mL, and the limits of detection are in the range of 0.03–0.27 ng/mL. Comparison with pristine MOFs, the performance of PCN-222@PCN-134 composite is significantly improved. The enrichment factors are obtained in the range of 254–333. The adsorption kinetics and adsorption isotherms are in accordance with pseudo-second-order and Langmuir models, respectively. The spiked recovery of real samples including egg and urine are between 76.4 and 120.1 % with relative standard deviation not higher than 12.1 %. After 14 times of use, the recovery rate of sorbent to SAs is still above 80 %. This work demonstrates that PCN-222@PCN-134 possesses excellent extraction performance to SAs, which can be used to clean-up and preconcentration of trace SAs in different sample matrices, such as egg and urine. [ABSTRACT FROM AUTHOR]

English elemental ordering in a non-canonical word order incorporates preposing, postposing and elemental reversal. This paper intends to explore how these types of elemental ordering are distributed during the last two centuries by employing the Corpus of Historical American English or COHA. The findings demonstrate that preposing has been increasing apparently but still in its inceptive phase; postposing, subsuming existential there and presentational there, generally keeps plateauing with existential there dominating presentational there; and elemental reversal experiences a trend of gradual decreasing, which is attributed to the dominance in occurrences of passive with a by phrase construction over those of inversion. This research provides us with a corpus linguistic insight of exploring elemental ordering, which distinguishes itself from other researches focusing on information status. [ABSTRACT FROM AUTHOR]

[Display omitted] • A magnetic multivariate MOF was synthesized by one-pot mixing ligand strategy. • 95.7 %BTB/MOF-525@Fe 3 O 4 was used as sorbent for adsorption and removal of bisphenols. • Maximum adsorption capacities ranging from 233.6 to 302.1 mg·g−1 for bisphenols. • The HPLC coupling with MSPE possesses low LODs with magnetic MTV-MOF as sorbent. • Sorbent exhibits excellent reusability with above 80% recovery after 21 times reuse. Herein, a magnetic multivariate metal–organic framework (MTV-MOF) named as 95.7 %BTB/MOF-525@Fe 3 O 4 was synthesized by one-pot mixing ligand strategy. The magnetic MTV-MOF exhibited large specific surface area (320 m2·g−1) and high porosity. The 95.7 %BTB/MOF-525@Fe 3 O 4 was used as sorbent for extraction and enrichment of bisphenol pollutants (BPs). The experimental results demonstrated that adsorption kinetics and isotherms conform to pseudo-second-order model and Langmuir model. The maximum adsorption capacities for bisphenol F, bisphenol A, bisphenol B, bisphenol AF were 275.1, 233.6, 302.1 and 277.2 mg·g−1, respectively. With 95.7 %BTB/MOF-525@Fe 3 O 4 as sorbent, the magnetic solid phase extraction coupling HPLC was used to detect trace BPs in environmental water. The limits of detection were determined as between 0.067 and 0.167 ng·mL−1. The enrichment factors were in the range of 242–295. The recoveries were ranged from 79.4 to 103 % with relative standard deviations not higher than 8.85 %. In addition, the recovery rate of sorbent remained above 80 % after 21 times of reuse. The work provides an effective material for extraction and removal of BPs in the environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new sensor for determination of PFOS by molecularly imprinted sensor was established. • The sensor was prepared by electrochemical polymerization using dopamine as a monomer. • Dopamine is a environment-friendly molecularly imprinted monomer compare with others. • The sensor exhibited good selectivity and repeatability. • The sensor presented excellent potential for monitoring of environmental water sample. This research aimed at developing an electrochemical sensor for the sensitive and selective determination of trace levels of Perfluorooctanesulfonic Acid (PFOS) in environmental water. The sensor (PFOS-MIPPDA/AuNPs/GCE) reported here is based on a glassy carbon electrode electrodeposition with gold nanoparticles (AuNPs) and modified with a molecularly imprinted polymer (MIP), which was prepared through the in situ electropolymerization of dopamine (DA) with PFOS as the template. Then, a new method for PFOS determination was established by differential pulse voltammetry using K 3 [Fe(CN) 6 ] as the detection probe. The optimal conditions for the preparation and analysis of the sensor were investigated. The surface morphology and electrochemical properties of the sensor were characterized by scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Results showed that the PFOS-MIPPDA/AuNPs/GCE sensor prepared by this method has good recognition performance, the linear range for PFOS detection is 0.01–8.00 µmol/L, and the detection limit is 0.0042 µmol/L. The result is satisfactory when used to analyze real water samples with recovery between 96.9 % and 104.6 %. This method has low cost, sensitive detection, and fast operation and has a potential application prospect for PFOS detection in environmental water samples. [ABSTRACT FROM AUTHOR]

Bacteria can be genetically engineered to act as therapeutic delivery vehicles in the treatment of tumors, killing cancer cells or activating the immune system. This is known as bacteria-mediated cancer therapy (BMCT). Tumor invasion, colonization and tumor regression are major biological events, which are directly associated with antitumor effects and are uncontrollable due to the influence of tumor microenvironments during the BMCT process. Here, we developed a genetic circuit for dynamically programming bacterial lifestyles (planktonic, biofilm or lysis), to precisely manipulate the process of bacterial adhesion, colonization and drug release in the BMCT process, via hierarchical modulation of the lighting power density of near-infrared (NIR) light. The deep tissue penetration of NIR offers us a modality for spatio-temporal and non-invasive control of bacterial genetic circuits in vivo. By combining computational modeling with a high-throughput characterization device, we optimized the genetic circuits in engineered bacteria to program the process of bacterial lifestyle transitions by altering the illumination scheme of NIR. Our results showed that programming intratumoral bacterial lifestyle transitions allows precise control of multiple key steps throughout the BMCT process and therapeutic efficacy can be greatly improved by controlling the localization and dosage of therapeutic agents via optimizing the illumination scheme. Programming intratumoral bacterial life style transitions allow precise control of multiple key steps throughout the bacteria-mediated cancer therapy process and therapeutic efficacy can be greatly improved by controlling the localization and dosage of therapeutic agents via optimizing the illumination scheme. [ABSTRACT FROM AUTHOR]

• Push-out test was performed on prefabricated composite shear stud (PCSS) connector. • High-resolution finite element (FE) analysis was made on the shear slip of PCSS. • Full-scale test was used to verify the application of PCSS in composite bridges. • Advanced FE analysis was made to explore the feature of PCSS in composite bridges. This paper has investigated the shear-slip behaviour of an innovative prefabricated composite shear stud (PCSS) connector and its application in the prefabricated steel–concrete composite bridges. A series of push-out tests are carried out on a total of 12 specimens, including 6 PCSS specimens and 6 conventional shear stud (CSS) specimens. Further comparison has been carried out between the test result and the data available from the literature. Based on the test, a high-resolution finite element (FE) analysis has been performed to reveal the load transfer mechanism of the PCSS connector at the component-level. After that, an advanced FE model has been established and validated by a full-scale test of the prefabricated composite bridge using the PCSS. With the FE model, the load-slip behaviour and slip distribution are investigated in details. The result highlights the enhanced shear capacity and ductility of the PCSS specimens compared with the CSS specimens, as well as the feasibility of PCSS connectors in composite bridges. Meanwhile, it is further revealed by the detailed investigation that the enhancement could be attributed to the lateral constraint on the concrete by the vertical steel plate in the PCSS. Besides, it is also found that the load-slip behaviour of composite bridges using the PCSS is influenced by the cracking at the seam between deck blocks. Consequently, abrupt changes can be found in the load-slip curve once the cracking occurs, which differs from the traditional composite bridges. [ABSTRACT FROM AUTHOR]

Favorable crop population architecture is the foundation for obtaining high crop yields and water productivity (WP) under limited irrigation. A field experiment was conducted at Wuqiao Experimental Station from 2015 to 2018 using the 'Nongda399′ wheat variety under the four seeding density and three irrigation schemes to explore the population architecture, canopy apparent photosynthesis (CAP), organ contribution, yield, and WP of winter wheat (Triticum aestivum L.). Compared with conventional high-yield cultivation (SD1W3), the water-saving cultivation (SD3W1) obtained a comparable yield meanwhile improved the WP in the range of 14.2–39.2%. The non-significant change in the yield under SD3W1 was primarily due to the increasing seeding density under W1 irrigation treatment, which improved the spike number and grains per unit area, especially the main stem spike, and had no significant effect on the thousand kernel weight (TKW). Increases in grain yield was generally caused by increases in CAP by constructing a reasonable canopy architecture with higher leaf area index (LAI) and non-leaf area index (NLAI) of the total canopy and upper strata, especially the spike area index (SAI) of the upper strata. Therefore, more light was intercepted by spikes, which improved the contribution of spike photosynthesis to yield. Increasing the seeding density also improved the assimilate remobilization contribution (RC) of pre-anthesis and decreased the post-anthesis leaf photosynthesis contribution to yield. Increasing the seeding density under limited irrigation improved the root length density (RLD), especially in 120–200 cm soil layer, which increased the absorption and use of deep soil moisture and improved WP. Overall, when sowing time from October 10–20, the appropriate seeding density of approximately 525–600 plants m−2 with 75 mm of irrigation at the jointing stage was the best cultivation practice for saving water and obtaining a comparable yield and a high water productivity of winter wheat in the North China Plain (NCP). • Increasing the seeding density improved the spike area index of the upper strata. • Higher seeding density improved the contribution of spike photosynthesis to yield. • Higher seeding density improved the contribution of remobilization before anthesis. • Increasing the seeding density improved the root length density in the deeper soil layers. • Increasing the seeding density under limited irrigation improved the yield and water productivity. [ABSTRACT FROM AUTHOR]

Porous polydivinylbenzene microspheres with high specific surface area were prepared by distillation–precipitation polymerization, and were used as the coating material in headspace solid phase microextraction for extracting polycyclic aromatic hydrocarbons. Compared with the other reported sorbents, PDVB exhibits lower cost and higher extraction efficiency, and the enrichment factors can reach 5963–16 720. [ABSTRACT FROM AUTHOR]

• Contribution of spikes photosynthesis to grain yield of wheat was 20%. • No current models explicitly consider contribution of spike photosynthesis to grain. • Simulation results of excluding & including spike contributions are investigated. • APSIM overestimated leaf contribution to compensate neglection of spike contribution. • Most current models may simulate wheat yield correctly partly for the wrong reasons. Process-based crop models are increasingly used to simulate Genotype by Environment by Management interactions (GxExM), and to evaluate importance of physiological traits to assist in breeding selections. This requires the model to correctly simulate the key physiological processes that determine grain yield. Although spike photosynthesis contributes to grain yield of wheat, it has not been explicitly simulated in most crop models. Here we present experimental data from China and Mexico, derived from estimates of spike contributions to grain yield of wheat, and compared them with previous results. We then used the APSIM model to investigate the consequences of excluding and including spike contributions on simulation results, against the data from China consisting of 4 irrigation and plant density treatments. Our results show that the contribution of spikes photosynthesis to grain yield ranged from 9.8% to 39.0% with an average of 20.1%, consistent with results from previous studies. However, despite the omission of the contribution from spike photosynthesis to grain yield, APSIM captured the dynamics of LAI and biomass and grain yield with acceptable accuracy. Across the treatments, the APSIM (version 7.9) explained >78% of the variation in yield (RMSE = 737 kg ha-1) and biomass (RMSE = 1438 kg ha-1) compared with the experimental data. This highlight the fact that APSIM performed well in simulating yield partly for the wrong reasons. Adding spike contribution to APSIM improved the simulations of biomass and yield, particularly under high yield level. More detailed analysis revealed that APSIM overestimated leaf contribution to compensate neglection of spike contribution, explained by the overestimation of leave biomass and underestimation of stem biomass. While APSIM captured the trend of changes in pre-anthesis remobilization contribution to grain yield, it also underestimated this contribution across treatments. Future improvements should include the inclusion of spike photosynthesis contribution with correct spike light interception and RUE, and improved modelling of biomass partitioning to different organs and the remobilization of biomass to grain from pre-anthesis growth. [ABSTRACT FROM AUTHOR]

The sensitive detection of polychlorinated biphenyls (PCBs) is crucial for protecting the environment and human health. Herein, we constructed a Materials Institute Lavoisier 88B (MIL-88B)-on-University of Oslo 66 (UiO-66) composite (MIL-on-UiO) with a unique nanoflower morphology, in which highly stable UiO-66 is the precursor, with MIL-88B grown on its surface. MIL-on-UiO was used as a fiber coating for headspace solid-phase microextraction to enrich PCBs. Experimental results demonstrated that MIL-on-UiO provided better enrichment performance for PCBs than single components due to multiple interactions, including π–π stacking, halogen bonding, pore-filling, and steric hindrance effects. The method established using the MIL-on-UiO-based SPME fiber coating provided a good linear relationship in the range of 0.001–50 ng·mL−1, with limits of detection ranging from 0.0002 to 0.002 ng·mL−1 and enrichment factors between 3530 and 7420. In addition, the method was used to detect trace PCBs in water and orange juice achieving satisfactory recoveries (81%–111%). • A MOF-on-MOF composite (MIL-on-UiO) with nano-flower morphology was constructed • The MIL-on-UiO was utilized as fiber coating of solid-phase microextraction to PCBs • High enrichment factor (3533–7421) to PCBs were achieved with MIL-on-UiO as coating • A HS-SPME coupling with GC-FID strategy for detecting PCBs has been developed [ABSTRACT FROM AUTHOR]

The role of miR-1179 in the development of cancer has been proved by different studies. However, the expression profile and role of miR-1179 is yet to be explored in human oral cancer. Consistently, this study was undertaken to explore the molecular role of miR-1179 in regulation of the human oral cancer development and progression. The results showed miR-1179 to be significantly (p < 0.05) overexpressed in all the oral cancer cell lines relative to normal cells. The repression of miR-1179 transcript levels not only suppressed the proliferation of oral cancer cells but also increased their sensitivity to vincristine. The decline in proliferative rates was attributed to induction of autophagy in oral cancer cells as confirmed by transmission electron microscopic analysis. Western blot analysis showed that the expression of LC3B-II increased and that of beclin 1 decreased while LC3B-I expression remained constant upon miR-1179 inhibition. Inhibition of miR-1179 caused significant decrease in the migration and invasion of the oral cancer cells. The migration and invasion found to be 47% and 32% for SCC-9 and 24% and 28% for SCC-25 cells upon miR-1179 inhibition. At molecular level, the miR-1179 was shown to exert its anticancer effects via deactivation of MEK/ERK and PI3K/AKT signalling cascades. In conclusion, the findings point towards the potential of miR-1179 in the treatment of oral cancer. [ABSTRACT FROM AUTHOR]

Water stress is a primary trigger for reducing grain number per spike in wheat during the reproductive period. However, under stress conditions, the responses of plant organs and the interactions between them at the molecular and physiological levels remain unclear. In this study, when water stress occurred at the young microspore stage, RNA-seq data indicated that the spike had 970 differentially expressed genes, while the stem, comprising the two internodes below the spike (TIS), had 382. Abscisic acid (ABA) signal transduction genes were down-regulated by water stress in both these tissues, although to a greater extent in the TIS than in the spike. A reduction in sucrose was observed, and was accompanied by increases in cell wall invertase (CWIN) and sucrose:sucrose 1-fructosyl-transferase (1-SST) activities. Hexose and fructan were increased in the TIS but decreased in the spike. ABA was increased in the spike and TIS, and showed significant positive correlation with CWIN and 1-SST activities in the TIS. Overall, our results suggest that water stress induces the conversion of sucrose to hexose by CWIN, and to fructan by 1-SST, due to increased down-regulation of ABA signal transduction related-genes in the TIS; this leads to deficient sucrose supply to the spike and a decrease in grain number. [ABSTRACT FROM AUTHOR]

• Rose-like ZnO was prepared by a green one-step CTAB-assisted hydrothermal method. • Rose-like ZnO was used as a fiber coating material of solid-phase microextraction. • Simultaneous HS-SPME of PCBs and PAHs with rose-like ZnO as coating was presented. • The rose-like ZnO exhibited excellent stability and durability. • The rose-like structure had better enrichment performance than rod-like structure. The three-dimensional (3D) rose-like zinc oxide (ZnO) material was prepared by a simple one-step CTAB-assisted hydrothermal strategy and used as a headspace solid-phase microextraction (HS-SPME) coating. Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography with flame ionization detector (GC-FID), and conclusively applied to ultrasensitive detection in lake and river water. Compared with one-dimensional (1D) pencil-like ZnO, the layer-by-layer petal-like structure could fully expose mass adsorption sites on the surface, which could significantly improve the adsorption. The enrichment factors with 7535–8595 for PCBs and 3855–7320 for PAHs were achieved. The established method provided a satisfactory linear range (0.005–30 ng·mL−1), coefficient (R2 > 0.9978), ultra-low limit detection (1–3 pg·mL−1), and long service life (≥ 150 times). The recoveries of 83.42–120.86 % were obtained in the real detection application of lake and river water. This work demonstrated that 3D rose-like ZnO with low cost, simple synthesis, fast extraction ability and high enrichment performance was an ideal coating material, which was hoped to enrich other compounds with similar structures with PCBs and PAHs. [ABSTRACT FROM AUTHOR]

Abstract Mesoporous silica nanoparticles (MSNs) have been widely studied as drug carriers to get sustained release behaviors, however, their application in sustained release of metoprolol tartrate (MPT) is limited. The possible reason is due to MPT molecule being bulky, while normal type MSNs like MCM-41 and SBA-15 have pore sizes of only 3–6 nm. In this study, two MCF-26 type MSNs were prepared with pore size of 11 or 15 nm, and used to conduct MPT release in comparison with MCM-41 and SBA-15. Both molecular simulation and MPT release experiments were performed to identify the pore size effect on adsorption and diffusion (release) of MPT in these MSNs. Finally, a kind of pH-sensitive MPT drug delivery system was obtained by coating the chosen MCF-26@MPT with an enteric polymer, which might find promising application in treating morning hypertension attack by orally administrating the drug delivery system before bedtime. Highlights • The adsorption and release of bulky metoprolol tartrate depend significantly on pore size of mesoporous silica. • Molecular simulation is helpful to determine the proper pore size for sustained release of metoprolol tartrate. • pH-Sensitive release of metoprolol tartrate from mesoporous silica is obtained via an enteric polyacrylic resin coating. [ABSTRACT FROM AUTHOR]

Due to widespread application of benzoylurea insecticides (BUs) and its persistence in environment, the effective capture of benzoylurea insecticides residues in environment is an important issue of environmental safety monitoring. To obtain excellent adsorption performance, creating defective structure in metal-organic frameworks (MOFs) can be employed as the method for adjusting its properties. Zirconium(Ⅳ)-based MOF termed as UiO-66-30% was constructed with 2-aminoterephthalic acid (NH 2 -BDC) and terephthalic acid (H 2 BDC) as building blocks. After calcination and removal of thermal-sensitive ligand (NH 2 -BDC), hierarchically porous UiO-66-30% (HP-UiO-66-30%) with multistage pore structure and good stability was obtained. The unique structure of HP-UiO-66-30% endowed it to achieve instantaneous equilibrium (within 2 min) when it was used as a dispersed solid phase extraction (d-SPE) adsorbent to extract BUs from environmental samples, greatly reducing the operation time. A wide linear range (0.05–200 ng mL−1), good linearity (R2 ≥ 0.9980), low detection limits (0.01–0.03 ng mL−1) and quantification limits (0.05–0.1 ng mL−1) were obtained for BUs. In addition, the HP-UiO-66-30% material possessed the good reusability and the adsorption capacity did not change significantly over 16 adsorption-desorption cycles. Finally, the established dispersed solid phase extraction-high performance liquid chromatography-diode array detector (d-SPE-HPLC-DAD) method was successfully applied to determination of BUs residues in environmental soil samples. The results demonstrated that HP-UiO-66-30% was an excellent sorbent for extraction BUs from environmental samples. [Display omitted] • Hierarchically porous HP-UiO-66-30% was obtained by forming defective structure. • The HP-UiO-66-30% presented multistage pore structures and good stability. • A dispersive solid-phase extraction using HP-UiO-66-30% as adsorbent was developed. • HP-UiO-66-30% provided excellent performance for enriching benzoylurea insecticides. [ABSTRACT FROM AUTHOR]

The stiffening girder of self-anchored suspension bridge (SSB) is subjected to huge axial force because the main cable is directly anchored on the end of the stiffening girder. To obtain a simple model and accurately understand the mechanical behavior of the whole structure in preliminary design, this paper proposed an analytical calculation method considering the combined effects of the main cable-suspender-stiffening girder. On the basis of the deflection theory of the stiffening girder, the relation between the girder shape and the suspender force was explored. The relation between the main cable end force (MCEF) and the suspender force was derived through segmental catenary theory, and iteration method was further improved to avoid the divergence condition. Finally the solution was obtained through satisfying the compatibility condition. The proposed method does not need to iterate manually and can save calculation time. Examples are introduced to verify the applicability of this method, with the result that this method considers the combined effects of the main cable-suspender-stiffening girder, and the finished bridge state satisfies the minimum strain energy of the stiffening girder. Results also indicate that this method has fast convergence speed and high precision. [ABSTRACT FROM AUTHOR]

Sample pretreatment plays important role in the analysis and detection of trace pollutants in complex matrices, such as environmental and biological samples. The adsorption materials of sample pretreatment receive considerable attention, which has a significant effect on the sensitivity and selectivity of the analytical method. In this work, the porous hexagonal boron nitride (h-BN) was utilized as a coating material of solid-phase microextraction (SPME) to extract and preconcentrate polycyclic aromatic hydrocarbons (PAHs) prior to separation and detection with GC-FID. Attributed to the multiple interactions including hydrophobicity, hydrogen bonding and strong π–π interaction, the h-BN coating showed excellent extraction performance for PAHs. Under the optimal conditions, the method showed the linear relationship in the range of 0.1–50 ng mL−1 for acenaphthene, 0.05–50 ng mL−1 for pyrene, and 0.02–50 ng mL−1 for fluorene, phenanthrene and anthracene with a correlation coefficient (R2) not lower than 0.9910. The enrichment factors were achieved between 1526 and 4398 for PAHs with h-BN as SPME fiber coating. The detection limits were obtained in the range of 0.004–0.033 ng mL−1, which corresponds to 0.08–0.66 ng g−1 for soil. The method was successfully applied to analysis of real soil samples. The recoveries were determined between 78.0 and 120.0% for two soil samples. The results showed that h-BN material provided a promising alternative in sample pretreatment and analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Fe 3 O 4 @MIL-100(Fe) with hollow nanoflower (HFs) morphology had been synthesized. • The shell thickness of MOF in Fe 3 O 4 @MIL-100(Fe) HFs is controllable. • The Fe 3 O 4 @MIL-100(Fe) HFs composite was used as adsorbent of solid-phase extraction. • The Fe 3 O 4 @MIL-100(Fe) HFs exhibited excellent enrichment performance for BUs. Developing a platform for the selective detection and effective monitor of toxic contaminants is a major challenge to address organic contaminants contamination in environmental science. Here, for the first time, the thickness-controllable Fe 3 O 4 @MIL-100(Fe) heterogeneous materials with special hollow nanoflower (HFs) morphology had been synthesized. The morphology and shell thickness of the nano-petal could be tuned by changing the reaction time. The resultant Fe 3 O 4 @MIL-100(Fe) HFs exhibited the hollow nanoflower shapes and exposed abundant accessible active sites. The enrichment performance of Fe 3 O 4 @MIL-100(Fe) HFs was approximately 1.4–1.7 times that of spherical Fe 3 O 4 @MIL-100(Fe) composite for benzoylurea insecticides (BUs). Furthermore, the optimal sample achieved the wide linearity (0.05–500 ng mL−1) and low limits of detection, (0.003–0.01 ng mL−1) for BUs. The research provides a new strategy for highly sensitive detection and monitoring of harmful pollutant levels in the environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The spindle-like Zn/Fe bimetallic MOF was prepared with high yield and high purity. • The morphology of NH 2 -Zn/Fe-MIL-88 can be rearranged by optimizing ratio of Zn2+/Fe3+. • NH 2 -Zn/Fe-MIL-88 was used as sorbent of dSPE to extract and enrich phytohormones. • The LODs of HPLC for analysis of phytohormones were achieved at 0.07–0.15 ng⋅mL−1. • Enrichment factors with NH 2 -Zn/Fe-MIL-88 as sorbent were obtained from 129 to 346. Amino-modified Zn/Fe bimetallic metal–organic frameworks (NH 2 -Zn/Fe-MIL-88) were synthesized using a one-step solvothermal method with FeCl 3 ·6H 2 O and Zn(NO 3) 2 ·6H 2 O as metal salts and 2-aminoterephthalic acid as organic ligand. The morphology of NH 2 -Zn/Fe-MIL-88 can be regulated from octahedral-like to spindle-like with changing molar ratios of metal salts. Using NH 2 -Zn/Fe-MIL-88 as sorbent, a dispersive solid-phase extraction with putting sorbents into sample solution to extract targets was developed to preconcentrate phytohormones in vegetables. To study the extraction efficiency, a series of NH 2 -Zn/Fe-MIL-88s with varying molar ratios of metal salts were prepared. The results indicated that NH 2 -Zn/Fe-MIL-88(1) presented the highest extraction efficiency (82.6 %–98.1 %) to phytohormones among all prepared NH 2 -Zn/Fe-MIL-88(x). The limits of detection were calculated at 0.07–0.15 ng/mL. The adsorption isotherms and kinetic parameters of NH 2 -Zn/Fe-MIL-88 for phytohormones were conformed to Langmuir and pseudo-second-order models. The NH 2 -Zn/Fe-MIL-88 as sorbent combined with HPLC was applied to detect phytohormones in cucumber and tomato samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchically porous Zr-based MOFs were prepared via modulator-induced strategy. • HP-NU-902-80 was used as sorbent to remove and enrich sulfonamide antibiotics (SAs) • The SAs can be completely removed within 10 min with HP-NU-902-80 as sorbent. • LODs and recoveries of the method were achieved at 0.08–0.25 ng/mL and 70.34–103.4 % • The maximum adsorption capacities of HP-NU-902-80 were 279.9–467.7 mg/g for SAs. Due to serious risk to human health and eco-environmental security, antibiotics in water and foods received considerable concern. Herein, a series of stable hierarchically porous zirconium-based metal–organic frameworks (MOFs) namely HP-NU-902-X were prepared via modulator-induced defect-guided formation strategy for the first time and functioned as sorbents to removal and preconcentration of sulfonamide antibiotics (SAs). The pore size and specific surface area of HP-NU-902-X were systematically adjusted by changing concentration of monocarboxylic acid modulator. The adsorption performance of HP-NU-902-X were greatly improved by forming defects. Experiments demonstrated that HP-NU-902-80 possessed the highest adsorption efficiency to SAs. The limits of detection (S/N = 3) were achieved ranging 0.08 to 0.25 ng/mL. The spiked recoveries of water and milk samples were obtained in the range of 70.34–103.4 % and 73.83–100.5 %. Enrichment factors were calculated between 203 and 358. The SAs can be completely removed within 10 min, and adsorption kinetic data was best consistent with pseudo-second-order model. Using Langmuir isotherm model, maximum adsorption capacities for sulfadiazine, sulfapyridine, sulfametoxydiazine, sulfachloropyridazine, sulfabenzamide and sulfamethazine were calculated as 279.9, 467.7, 414.4, 433.1, 415.5 and 336.6 mg/g, respectively. The improved adsorption capacity was mainly owing to high surface area and extra defect sites. This synthetic strategy provides a way to prepare stable defective MOFs and enhance their potential applications in removal and extraction of environmental pollutants. [ABSTRACT FROM AUTHOR]

BRCA1-interacting protein 1 (BRIP1), a DNA-dependent ATPase and a DNA helicase, is critical for BRCA-associated DNA damage repair functions and may be associated with the tumourigenesis and aggressiveness of various cancers. Here, we constructed a BRIP1 recombinant plasmid, overexpressed it in a cervical cancer cell line (HeLa) and found that ectopic expression of BRIP1 could remarkably enhance the antitumor activity of cisplatin, as demonstrated by decreased cell viability, colony formation and tumour xenografts' weight. Moreover, BRIP1 promoted cisplatin-mediated cell apoptosis and suppressed tumour angiogenesis. We also found that the synergistic inhibition effect of BRIP1 might be partially attributed to attenuation of Rac1 GTPase activation and that Rac1 GTPase re-activation could reverse the sensitizing effect induced by BRIP1. Our study suggested that up-regulation of BRIP1 could enhance chemosensitivity of HeLa cells to cisplatin through inhibiting Rac1 GTPase activation, and it provides a new insight into the essential role of BRIP1 in cervical cancer chemotherapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like Co 3 O 4 /C 3 N 5 nanocomposite was synthesized by one-pot solvothermal method. • The Co 3 O 4 /C 3 N 5 composite was used as fiber coating of solid-phase microextraction. • The Co 3 O 4 /C 3 N 5 as fiber coating exhibited high thermal stability (more than 400 ℃) • Good adsorption performance and high enrichment factors (3010–6180) were achieved. Sensitive detection of environmental pollutants that are harmful to organisms is of great significance for prevention of related diseases. In this work, a flower-like Co 3 O 4 /C 3 N 5 composite as solid-phase microextraction fiber coating was developed for extraction of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The Co 3 O 4 /C 3 N 5 composite was derived from the multilayer stacked flower shaped Co(OH) 2 /C 3 N 5 that synthesized by one-pot solvothermal method. Compared with pure monomer materials, the unique structure was maintained and the surface adsorption sites were fully exposed, thereby the adsorption performances of Co 3 O 4 /C 3 N 5 were significantly improved. As a result, the enrichment factors were 3010–5012 for PAHs, and 4499–6180 for PCBs. Under the optimized conditions, the developed method showed wide linear range (0.0005–20 ng mL−1) with good linearity (R2 greater than 0.9912), low detection limits (0.00017–0.061 ng mL−1, S/N = 3) and quantification limits (0.0005–0.2 ng mL−1, S/N = 10) for three PAHs and five PCBs. The RSDs (n = 5) of intraday and interday were 2.28–8.35% and 3.49–9.59%, respectively. The reproducibility between fibers (n = 3) was in the range of 7.84–11.96%. The developed method was successfully applied to real water sample with satisfactory recoveries of 81.07–109.1%. As a simple and robust technique, the proposed method will be an alternative way to the analysis of PAHs and PCBs in real samples. [ABSTRACT FROM AUTHOR]

Illustration of the preparation of magnetic carbon nanotube-decorated nitrogen-doped carbon (CNT/Fe@N-C) samples and organic dyes adsorption process. [Display omitted] • Magnetic carbon nanotube-decorated nitrogen-doped carbon (CNT/Fe@N-C) was prepared. • The magnetic CNT/Fe@N-C composite provides good performance to remove organic dyes. • The results indicate that the adsorption is the monolayer chemisorption process. • A new strategy is provided to prepare CNT/metal@N-doped carbon hybrid materials. In this work, a magnetic carbon nanotube-decorated nitrogen-doped carbon (CNT/Fe@N-C) composite was successfully prepared by carbonization of melamine and MIL-101(Fe) under inert atmosphere at 900 °C. In order to study the removal performance of adsorbents for the organic dyes, different mass ratios melamine/MIL-101-derived CNT/Fe@N-C were prepared. The results show that the as-prepared CNT/Fe@N-C material delivers a high performance for removal of organic dyes (Rhodamine B, malachite green, and methyl orange) with mass ratio of MIL-101(Fe) and melamine at 1:3. The experimental parameters including amount of adsorbent, pH, contact time, and initial concentration of organic dyes were investigated. Under the optimized conditions, the maximum adsorption amount of CNT/Fe@N-C for three dyes are in the range of 182.1–196.5 mg/g. The adsorption process of three dyes on the CNT/Fe@N-C material was consistent with Langmuir isotherm model and pseudo-second-order model. The results indicate that the adsorption may be the monolayer chemisorption process. The adsorption mechanism of organic dyes on the adsorbent material is may be due to the electrostatic interactions and π-π stacking interaction. Finally, the CNT/Fe@N-C material can be reused 5 times without a significant reduction in the removal rate. The results indicate that the CNT/Fe@N-C material is a promising sorbent for removing organic dyes. This work provides a new strategy to prepare CNT/metal@N-doped carbon material with excellent adsorption properties from nitrogen-free raw MOF materials by calcining a mixture of MOF and melamine at high temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • Vision-based modal parameter identification was assessed for bridge structural health monitoring. • HVS and identification algorithms were developed for structural damage detection. • The superiority of vision-based modal parameters in damage detection was demonstrated. • Improved sensor efficiency and reduced cost responses were demonstrated. Noncontact monitoring using holography can be quite useful in vision-based structural health monitoring owing to its advantages in terms of data visualization and real-time applications. Aimed at exploring the potential of vision-based sensors for structural health monitoring in more general applications, this paper has developed the holographic visual sensor (HVS) with a vision-based modal parameter identification method. This strategy is an extension of the current vision-based techniques and holography. Based on the newly introduced spatial and temporal sequence data measured by HVS, the vision-based modal parameter identification method was proposed and applied to structural health monitoring for the first time. Accordingly, the feature point set describing the geometric morphology of the structural holography and the time-state-space mathematical model of the structural dynamics system was constructed. In this way, the mechanical behavior characteristics could be extracted from serial transient holographic responses following excitation, and the structural modal parameters were then calculated and quantitatively analyzed. Laboratory experiments and field tests were employed for validation based on the comparison between the results determined by the proposed HVS and those determined by conventional, high-precision contact sensors. The developed HVS and identification algorithms were able to visually collect and identify modal parameters at a higher data resolution and provide smoother modal shapes. The proposed method can thus be used to complement and improve existing computer-vision-based measurement techniques and damage detection. [ABSTRACT FROM AUTHOR]

• Predicting micronutrients in wheat kernel and flour using hyperspectral imaging. • The prediction of micronutrients was superior based on the kernel spectra compared to the use of flour spectra. • The Ca, Mg, Mo and Zn nutrients in wheat kernel/flour were predicted with a high credibility. Micronutrients are the key factors to evaluate the nutritional quality of wheat. However, measuring micronutrients is time-consuming and expensive. In this study, the potential of hyperspectral imaging for predicting wheat micronutrient content was investigated. The spectral reflectance of wheat kernels and flour was acquired in the visible and near-infrared range (VIS-NIR, 375–1050 nm). Afterwards, wheat micronutrient contents were measured and their associations with the spectra were modeled. Results showed that the models based on the spectral reflectance of wheat kernel achieved good predictions for Ca, Mg, Mo and Zn (r2 > 0.70). The models based on the spectra reflectance of wheat flour showed good predictive capabilities for Mg, Mo and Zn (r2 > 0.60). The prediction accuracy was higher for wheat kernels than for the flour. This study showed the feasibility of hyperspectral imaging as a non-invasive, non-destructive tool to predict micronutrients of wheat. [ABSTRACT FROM AUTHOR]

Excessive nitrogen (N) application rates and serious over-exploitation of groundwater under farmer practice threatens the sustainable use of resources in the North China Plain (NCP). Crop canopy structure affects light distribution between leaves, which is important to determine crop growth. A field experiment conducted from October 2016 to June 2019 in the NCP was designed to examine whether optimum water and nitrogen management could optimize canopy characteristics to improve yield and resource use efficiency. Field treatments included: (1) an example of local farming practices, which include the addition of 330 kg N ha−1 and irrigated twice (FP), (2) a reduced N rate of 270 kg N ha−1 and irrigated twice (T1), (3) a reduced rate of N rate of 210 kg N ha−1 and irrigated once (T2), and (4) no N applied (0 kg N ha−1) and irrigated once (T3). Results showed that the highest yield was in T1 treatment during 3 years' winter wheat growing seasons. Water use efficiency (WUE), N use efficiency (NUtE), and N partial factor productivity (PFPN) were significantly higher in T2 treatment than in FP, and the three-year average yield was 9.4% higher than that at FP. Optimum crop management practice (T1 and T2) improved canopy structure characteristics, with less relative photosynthetically active photon flux density (PPFD) penetrated of canopy and higher population uniformity as well as leaf area index, to coordinate the distribution of light within the canopy and maximize canopy light interception, resulting in higher yield and resource use efficiency. Leaf area index (LAI) and specific leaf area (SLA) were closely correlated with grain yield and WUE, while PPFD penetrated of canopy was negatively and significantly correlated with grain yield and WUE. The results indicate that canopy structure characteristics, especially PPFD and population uniformity are good indicators of yield and resource use efficiency. [ABSTRACT FROM AUTHOR]

• The maximum number of floret primordia was hardly affected by treatments. • Florets that have started abortion can not become fertile florets. • Anthers development determines the number of fertile florets. • Nitrogen application accelerated the rates of floret development and hence increased the number of fertile florets. The dynamics of floret initiation/abortion has been explored widely; however, the mechanisms of increasing floret fertility at anthesis in wheat production remain unclear. In this study, morphological and physiological responses of florets per spikelet and per spike to nitrogen and irrigation treatments in the field were investigated. Each spikelet produced the maximum number of living floret primordia (MFP) and showed no difference between treatments at the W7.5 stage; this ability was hardly affected by treatments. We firstly found that gradually abortive florets during W8.5-W10 stages were delayed due to improving assimilates availability in the spike instead of the 4th-5th inthernode; in fact, these florets would be aborted completely and never become fertile florets. Notably, we found that those florets in which the anther turned green (value ≥ 97) at W7.5 always became fertile, and their number showed a significant positive relationship with number of fertile florets (NFF) at W10. Collectively, more available assimilates in spike accelerated anther turning green during period of early floret development, maintained their development normally and becoming fertile florets, but did not make florets that initiate abortion become fertile florets and increase the MFP. [ABSTRACT FROM AUTHOR]

• A water-saving method considering winter wheat-summer maize rotation was investigated. • New method saved 1126 m3 ha−1 of water with comparable rotation yield to the current irrigation management. • Increased maize yield compensated the elimination in wheat yield. • Higher received precipitation in maize while not temperature explained increased yield. Water scarcity in the North China Plain (NCP) is threatening irrigation of predominant winter wheat-summer maize rotation and thus rotation yield. To maximally reduce irrigation input while maintaining relatively high yield is urgently needed and an enduring challenge. Here we present an innovative practice that considers the water use of the entire rotation system, i.e., application of presowing irrigation to reach 85% of the field capacity for wheat (W0) compared with the common practice of applying twice more irrigation with each 750 m3 ha−1 during the wheat season (W2). After sowing maize, 750 m3 ha−1 irrigation was applied for both practices. The main hypothesis was that reducing wheat irrigation would lead to lower water content in the soil, which would in turn preserve more rain in the maize season, and that earlier maturity of wheat caused by reduced irrigation would advance earlier maize-sowing to utilize more radiation and thermal inputs resulting in higher maize yield which would compensate for decreased wheat yield. From 2012 to 2016, the 0–200 cm soil water contents, as well the yield and its components, were monitored at key growth stages of wheat and maize. There was consistently lower water content under W0 than under W2 from flowering to maturity of wheat making 4–5 days earlier maturity under the W0 practice, and led to a higher accumulated temperature of maize relative to the W2 practice. The grain yields of wheat, maize and rotation were 6694 to 9218 kg ha−1, 7284 to 12,843 kg ha−1, 16,336 to 20,605 kg ha−1, respectively. The temperature accumulated after silking well explained the interannual variation in maize yield. In contrast to temperature, rainfall during the maize season explained the yield difference between two practices. The maize yield was 6.4% higher under the W0 practice than under the W2 practice, in a year with sufficient rainfall, above 451 mm, and this trend was unpronounced under rare drought stress, below 250 mm of rainfall, leading to a 7.5% lower yield. The average yield of the four rotation rounds under W0 was equal to that under W2. Nevertheless, the W0 practice significantly increased the water use efficiency under rotation by 12.9%. On average, the irrigated amount in each rotation under W0 was significantly reduced by 1126 m3 ha−1 relative to W2. Therefore, the W0 practice is a simple and promising water management strategy for addressing shortages of water and labor while maintaining relatively high rotation yield in the NCP. [ABSTRACT FROM AUTHOR]

• Compared to TI120, MI120 and MI150 significantly increased grain yield and WUE. • MI90 ensured grain yield by significantly improving thousand grain weight. • Except for MI60, MI treatments significantly delayed the senescence of flag leaf during grain filling. • MI treatments ensured the water supply in the mainly root distribution zone of wheat. • MI with reducing irrigation promoted water consumption of the deep soil profile. It's very important to guarantee the wheat production and improve water productivity in the North China Plain (NCP). In order to reduce irrigation and ensure the crop production in the NCP, a two-year field experiment of winter wheat was conducted in 2016–2018 using micro-sprinkling irrigation including different irrigation amount treatments (60 mm, MI60; 90 mm, MI90; 120 mm, MI120; and 150 mm, MI150), and the local traditional water-saving and productive flooding irrigation method (TI120) was as a control. The grain yield (GY), dry matter accumulation (DM), root system distribution and water utilization were investigated. The results showed that, the GY of MI60 decreased by 5.1–13.4% compared with TI120; GY of MI90 was comparable with TI120, while that of MI120 and MI150 increased significantly. The higher GY in micro-sprinkling treatments was mainly due to the significant increase of 1,000-grain weight (TGW), which was the result of the significant delay of the senescence in flag leaves during grain filling and then the increase in the post-anthesis DM. In addition, the roots mainly distributed in the 0−60 cm soil profile, and micro-sprinkling ensured the soil water supply in this areas at the critical growth stages; what's more, micro-sprinkling with reducing irrigation treatments significantly promoted the growth of root system to the deep soil layer, which improved the absorption and utilization of moisture stored in soil. Compared with TI120, the same irrigation amount treatment under micro-sprinkling (MI120) significantly increased water use efficiency (WUE) due to higher GY and lower seasonal evapotranspiration (ET); the 125% irrigation amount treatment (MI150) increased WUE due to higher GY and comparable ET; the 75% irrigation amount treatment (MI90) obtained the similar WUE to TI120; the 50% irrigation amount treatment (MI60) got similar or lower WUE to TI120. Overall, suitable reduction of irrigation amount under micro-sprinkling (MI90) can ensure the grain yield of winter wheat and efficient utilization of irrigation water in the NCP. [ABSTRACT FROM AUTHOR]