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Three-dimensional (3D) well-crystallized metal-organic frameworks (MOFs), M-THBQ (M = Fe, Co, Mn, THBQ = tetrahydroxybenzoquinone), are synthesized and characterized. Their structures are determined as cubic cell in the group of Pm-3 from powder X-ray diffraction data, and their properties of electronic, magnetic and spectroscopic are also investigated. They are all semiconductors, and Fe-THBQ exhibits the air-stable n-type thermoelectric characteristic as its Seebeck coefficient reaches -130 μV K-1, and the electrical conductivity is 2.7 x 10-4 S cm-1 at 300 K. Additional, M-THBQ are paramagnetic, and the value of Weiss constant of Fe-THBQ is -219.37 K, indicating the existence of robust intramolecular antiferromagnetic exchanges. Meanwhile, they display strong absorption bands in the range of 220 to 1000 nm, suggest M-THBQ could have the potential to become photoabsorbers, and Fe-THBQ exhibits a narrow bandgap of 0.63 eV according to the ultraviolet absorption edge spectrum. The successful preparation of M-THBQ enriches the family of 3D magnetic conductive MOFs.

In the past decade, chemical-fuel-driven processes have been integrated with synthetic self-assembled systems, in which both the formation and properties can be carefully controlled. This strategy can drive systems far away from equilibrium, tailor the lifetime window of transient self-assembled systems, thus holding promise for future smart, adaptive, self-regulated, and life-like systems. By judging whether the building blocks or transient self-assembled systems participate in the fuel-to-waste conversion, the reported systems can be divided into two classes: dissipative self-assembly and self-assembly under dissipative conditions. Among these systems, the utilization of macromolecular building blocks to design non-equilibrium self-assemblied systems is becoming common. Macromolecular systems capable of dissipating energy with a programmed time domain have found widespread application, and have therefore been an active field of scientific inquiry. This Minireview aims to highlight the recent progress and opportunities of chemical-fuel-driven assembly in macromolecules. We envision that chemical-fuel-driven approach will play an increasingly important role in polymer science in the near future.

AIMS: Chinese children are more susceptible to the development of thiopurine‐induced leukopenia compared with Caucasian populations. The aim of our study was to establish a 6‐mercaptopurine (6‐MP) dose–concentration–response relationship through exploration of pharmacogenetic factors involved in the thiopurine‐induced toxicities in Chinese paediatric patients afflicted by acute lymphoblastic leukaemia (ALL). METHODS: Blood samples were obtained from ALL children treated with 6‐MP. We determined the metabolite steady‐state concentrations of 6‐MP in red blood cells (RBCs) by using high‐performance liquid chromatography. Pharmacogenetic analysis was carried out on patients' genomic DNA using the MassArray genotyping platform. RESULTS: Sixty children afflicted by ALL who received 6‐MP treatment were enrolled in this study. The median concentration of 6‐thioguanine in patients afflicted by leukopenia was 235.83 pmol/8 × 10(8) RBCs, which was significantly higher than for patients unafflicted by leukopenia (178.90 pmol/8 × 10(8) RBCs; P = 0.029). We determined the population special target 6‐thioguanine threshold to have equalled 197.50 pmol/8 × 10(8) RBCs to predict leukopenia risk in Chinese paediatric patients afflicted by ALL. Among 36 candidate single nucleotide polymorphisms, our results indicated that NUDT15 (rs116855232) and IMPDH1 (rs2278293) were correlated with a 5.50‐fold and 5.80‐fold higher risk of leukopenia, respectively. MTHFR rs1801133 variants were found to have had a 4.46‐fold significantly higher risk of hepatotoxicity vs wild‐type genotype. CONCLUSION: Our findings support the idea that predetermination of genotypes and monitoring of thiopurine metabolism for Chinese paediatric patients afflicted by ALL is necessary to effectively predict the efficacy of treatments and to minimize the adverse effects of 6‐MP maintenance therapy.

Non-Newtonian fluids are ubiquitous in daily life and industrial applications. Herein, we report an intelligent fluidic system integrating two distinct non-Newtonian rheological properties mediated by an autocatalytic enzyme reaction. Associative polyelectrolytes bearing a small amount of ionic and alkyl groups are engineered: by carefully balancing the charge density and the hydrophobic effect, the polymer solutions demonstrate a unique shear thickening property at low pH while shear thinning at high pH. The urea-urease clock reaction is utilized to program a feedback-induced pH change, leading to a strong upturn of the nonlinear viscoelastic properties. As long as the chemical fuel is supplied, two distinct non-Newtonian states can be achieved with a tunable lifetime span. As a proof of concept, we demonstrate how the physical energy-driven nonequilibrium properties can be manipulated by a chemical-fueled process.

Here, we propose a novel imaging method, which is called image scanning difference microscopy (ISDM), for superresolution imaging. In ISDM, we implement a detector array composed of 19 avalanche photodiodes (APD) rather than single-point detector in standard confocal microscopy for reconstructing superresolved images with higher signal-to-noise ratio (SNR). Combining with our former proposed fluorescence emission difference (FED) method, we have achieved a lateral resolution of 111 nm (∼λ/6) without the damage of image quality, the highest FED resolution to the best of our knowledge. With its simple setup and remarkable performance, we believe that ISDM can become a versatile observation tool in biology and other fundamental studies. LAY DESCRIPTION: Fluorescence emission difference (FED) microscopy is a really simple and generalisable superresolved fluorescence microscopy method based on PSF engineering and difference algorithm recently. Compared to stimulated-emission-depletion fluorescence microscopy (STED), FED don't need complicated system or precise alignment and polarisation, available for wide variety of dyes and has low photobleaching and phototoxicity for living cells. However, the distortion caused by negative value is one of the biggest obstacles to the further development of FED. In light of this, we propose a novel superresolution imaging method based on the FED method with parallel detection system, which is called image scanning difference microscopy (ISDM). Our method has achieved a significant breakthrough in FED, increasing the resolution further while reducing artefacts generated by negative values, which cannot be accomplished through combining other methods. In addition, ISDM does not require complex setup and optical alignment, long time imaging and imposing no constraint on dyes. Importantly, we realised a transverse resolution of ∼λ/6 (triple diffraction limit) with single wavelength, single incident path and low light intensity, which has never been achieved in any other far-field superresolution microscopy.

With the development of green chemistry, it is still a challenge to maintain the unstable valence state of the metal in heterogeneous catalysts and realize new catalytic synthesis methods. In this paper, it was reported that an univalent copper nanocomposite (Cu@Al/SBA-15) could efficiently catalyze the formation of novel amino-containing benzotriazoles with great fluorescence properties in a new synthetic strategy. Subsequently, its application was further verified by acylation reaction to produce a series of novel benzotriazoles derivatives with high yield. It was worth noting that Cu@Al/SBA-15 nanocomposites not only enable the reaction completed with high yield in a short time, but also could be recycled many times without a significant reduction in activity, and the leaching of copper and aluminum species in reaction system was negligible. Finally, the detailed and feasible reaction mechanism was also provided.

The design of structurally dynamic molecular networks can offer strategies for fabricating stimuli-responsive adaptive materials. Herein we first report a gas-responsive dynamic gel system based on frustrated Lewis pair (FLP) chemistry. Two trefoil-like molecules with bulky triphenylborane and triphenylphosphine groups are synthesized as complementary Lewis acid and base with trivalent sites. They can together bind CO2 gas molecules and further form a cross-linked network via the bonding interactions between FLPs and CO2 . Such CO2 -bridged dative linkages are shown to be dynamic covalent bonds, which endow the frustrated Lewis network with adaptable behaviors and unprecedented gas-regulated viscoelastic, mechanical, and self-healing performance. This study is an initial attempt to apply the FLP concept in materials chemistry, but we believe that this strategy will open a promising future for gas-sensitive smart materials.

Aims Nephrotic syndrome (NS) is the most common clinical manifestation of glomerular disease in children. Currently, tacrolimus (TAC) is widely used in children with NS. However, pharmacokinetic data in children with nephrotic syndrome is limited. This study was intended to evaluate the population pharmacokinetics (PPK) of TAC in paediatric NS and to optimize dosing regimen. Methods Blood samples from NS children treated with TAC were collected and the blood concentrations of TAC were detected using HPLC-MS/MS. A PPK model was developed using NONMEM software. Pharmacogenetic analysis was carried out in the CYP3A5 gene. Results The data from 28 children were used for PPK analysis. A one-compartment model and first-order elimination were accorded with the TAC data in paediatric NS. A covariate analysis showed that body weight and CYP3A5 genotype significantly affected TAC pharmacokinetics. Monte Carlo simulation indicated that NS children with CYP3A5*3/*3 receiving 0.10 mg kg-1 dose-1 twice daily and NS children with CYP3A5*1 receiving 0.25 mg kg-1 dose-1 twice daily TAC could achieve the target concentrations of 5-10 ng ml-1 . Conclusion The PPK of TAC was estimated in children with NS and a CYP3A5 genotype-based dosing regimen was set up based on simulations.

A series of 8-(arylimino)-5,6,7-trihydroquinolines ligand pendant fluorenyl group at N-aryl ring, and their nickel complexes (Ni1 − Ni5) have been prepared and characterized. Once activated with Et2AlCl, the complexes Ni1, Ni2, and Ni3 bearing ligands from para-fluorenylaniline produced unimodal polyethylenes; on the contrary complexes Ni4 and Ni5 gave bimodal polyethylenes due to steric influence of ligands from ortho-fluorenyl anilines. With a increment of Et2Zn/Ni4 ratio from 0 to 400, the distinct bimodel polyethylenes were obtained with molecular weights shifted from 14.3 to 57.6 kg·mol−1; apart shiftment to higher molecular weights, the portion of low molecular weight decreased along with higher portion of high molecular weight. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1910–1919

A series of 2-(1-(2,4-dibenzhydrylnaphthylimino) ethyl)6-(1-(arylimino) ethyl) pyridyliron(II) complexes (Fe1-Fe5) was synthesized and characterized. The molecular structure of the representative Fe2 was determined by single-crystal X-ray diffraction, revealing a distorted pseudo-square-pyramidal geometry around the iron center. On activation with eithermethyl aluminoxane (MAO) or modified methylaluminoxane (MMAO), all these iron complex precatalysts performed with high activities (up to 1.58 x 10(7) g (PE) mol(-1) (Fe) h(-1)) toward ethylene polymerization, producing highly linear polyethylenes with highmolecular weight and bimodal distribution, which was in accordance with high temperature C-13 NMR, high T-m values (T-m similar to 130 degrees C) and the GPC curves of the obtained polyethylenes. Meanwhile, DFT calculation results also showed the good correlation between net charges on iron and experimental activities. Compared with previous bis(imino) pyridyliron analogues, the current iron complexes containing the benzhydrylnaphthyl groups exhibited relatively higher activities and better thermalstability at elevated temperatures, especially at 80 degrees C as the industrial operating temperature, and still showed high activities toward ethylene polymerization up to 8.57 x 10(6) g (PE) mol(-1) (Fe) h(-1) in the presence of co-catalyst MMAO. In addition, these iron complex precatalysts all exhibited long lifetimes. (C) 2017 Wiley Periodicals, Inc.

Computational spectroscopic instruments with Broadband Encoding Stochastic (BEST) filters allow the reconstruction of the spectrum at high precision with only a few filters. However, conventional design manners of BEST filters are often heuristic and may fail to fully explore the encoding potential of BEST filters. The Parameter Constrained Spectral Encoder and Decoder (PCSED) - a neural network-based framework is presented for the design of BEST filters in spectroscopic instruments. By incorporating the target spectral response definition and the optical design procedures comprehensively, PCSED links the mathematical optimum and practical limits confined by available fabrication techniques. Benefiting from this, the BEST-filter-based spectral camera present a higher reconstruction accuracy with up to 30 times' enhancement and a better tolerance on fabrication errors. The generalizability of PCSED is validated in designing metasurface- and interference-thin-film-based BEST filters.

The properties of optical vortex provide new insights into a wide range of optical and physical phenomena, giving rise to numerous applications in multiple disciplines. Notably, as much as the associated technologies have become increasingly flexible, it is still challenging to simultaneously generate multiple longitudinal polarization optical vortices with random topological charges (l) and tunable intensities at arbitrary positions. Herein, a novel approach that, by manipulating phase and amplitude at the back pupil of a high numerical‐aperture (NA) objective, realizes arbitrary longitudinal polarization vortices within the tightly focused light field is developed. Building upon the same model, the impacts of polarization on the optical vortex field and its potential of tuning the ratio of the longitudinal polarization component are further investigated.

Solid state emissive materials with high quantum yields and tunable emissions are desirable for various applications. A new TPE derivative (1) with two carbazole moieties and two cyano groups is reported, which shows typical aggregation induced emission behavior. Four crystals 1a, 1b, 1c, and 1d are obtained after crystallization from N,N-dimethylformamid (DMF), trichloromethane (CHCl3 ), tetrahydrofuran (THF), and dichloromethane (CH2 Cl2 ), respectively. Crystal structural analyses reveal that (i) molecules of 1 co-crystallize with DMF, CHCl3 , THF, and CH2 Cl2 in 1a, 1b, 1c, and 1d, respectively, and (ii) conformations of 1 are different within 1a, 1b, 1c, and 1d, and compound 1 within crystal 1a adopts the most twisting conformation. Crystalline solids 1a, 1b, 1c, and 1d exhibit high emission quantum yields up to 0.65, but their emission colors are varied from blue to green. In comparison, the amorphous solid of 1 is yellow-emissive with emission maximum at 542 nm. Moreover, the blue- or green-emissive crystalline solids and the yellow-emissive amorphous solid can be inter-converted by the grinding of crystalline solids and exposure of the amorphous solid to vapors of appropriate solvents. It is also demonstrated that microrods of 1a, 1b, and 1d show typical optical waveguiding behavior.

Herein we describe a scalable four-step preparation of α-methylene-γ-lactone 3 from steroidal sapogenin. This method allowed a facile synthesis of clionamine D, a natural aminosteroid with potent autophagy bioactivity and unprecedented chemical structure.

BACKGROUND Soil organic carbon (SOC) is fundamental for mitigating climate change as well as improving soil fertility. Databases of SOC obtained from soil surveys in 1981 and 2011 were used to assess SOC change (0–20 cm) in croplands of Heilongjiang Province in northeast China. Three counties (Lindian, Hailun and Baoqing) were selected as typical croplands representing major soil types and land use types in the region. RESULTS The changes in SOC density (SOCD) between 1981 and 2001 were −6.6, −14.7 and 5.7 Mg C ha−1 in Lindian, Hailun and Baoqing Counties respectively. The total SOC storage (SOCS) changes were estimated to be −11.3, −19.1 and 16.5% of those in 1981 in the respective counties. The results showed 22–550% increases in SOCS in rice (Oryza sativa L.) paddies in the three counties, but 28–33% decreases in dry cropland in Lindian and Hailun Counties. In addition, an increase of 11.4 Mg C ha−1 in SOCD was observed in state-owned farms (P < 0.05), whereas no significant change was observed in family-owned farms. CONCLUSION Soil C:N ratio and initial SOCD related to soil groups were important determinants of SOCD changes. Land use and residue returning greatly affected SOC changes in the study region. To increase the topsoil SOCD, the results suggest the conversion of dry croplands to rice paddies and returning of crop residue to soils. © 2015 Society of Chemical Industry

A series of 1-(2,6-dibenzhydryl-4-fluorophenylimino)- 2-aryliminoacenaphthylene derivatives (L1-L5) and their halonickel complexes LNiX2 (X=Br, Ni1-Ni5; X=Cl, Ni6-Ni10) are synthesized and well characterized. The molecular structures of representative complexes Ni2 and Ni4 are confirmed as the distorted tetrahedron geometry around nickel atom by the single crystal X-ray diffraction. Upon activation with methylaluminoxane, all nickel complexes show high activities up to 1.49 x 10(7) g of PE (mol of Ni)(-1) h(-1) toward ethylene polymerization, producing polyethylenes with high branches and molecular weights up to 1.62 x 10(6) g mol(-1) as well as narrow polydispersity. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1369-1378

Optimal resolution by stimulated emission depletion (STED) microscopy requires precise alignment of the donut-shaped depletion focus to the excitation focus. In this article, we demonstrate that fluorescence lifetime distribution can be implemented to align the STED system. Different from the traditional aligning methods in which a scattering imaging module is often equipped, the lifetime-based method is free from probable mismatches between the scattering mode and the fluorescent mode, drift errors caused by separate imaging and complex fitting methods. Based on this method, a spatial resolution of 38 nm by time-gated detection has been achieved. Microsc. Res. Tech. 77:935–940, 2014. © 2014 Wiley Periodicals, Inc.