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Aluminum is a widely distributed element and plays an indispensable role in our lives, but excessive intake of Al3+ can cause potential harm to human health. Highly selective methods for the rapid detection of Al3+ are urgently needed. Here, a novel "turn on" fluorescent probe L based on Schiff-base of 2-hydroxy-1-naphthaldehyde and 8-aminoquinoline was obtained in an excellent yield. Probe L presents significant properties such as rapid response, good stability, wide pH range, simple synthetic operation, and provides an efficient strategy for the highly selective detection of Al3+ in an aqueous solution of DMSO/H2O (7:3, v:v). According to Job's curve and fluorescence titration, probe L with Al3+ forms a 2:1 ratio of complex, and the lowest limit of detection is 3.23 × 10−8 mol/L. The possible combination mode for probe L with Al3+ was proposed by comparison with the changes of 1H NMR and FTIR spectra of L and its complex. In addition, the potent applicants for probe L were also investigated, and indicated that it could conveniently be made into a series of sensor strips and applied to rapidly detect trace Al3+ in traditional Chinese medicine. [ABSTRACT FROM AUTHOR]

A chiral bispyrene macrocycle designed for exclusive intermolecular excimer fluorescence upon aggregation was synthesized by a double hydrothiolation of a bis‐enol ether macrocycle followed by intramolecular oxidation of free thiols. Unusually high stereoselectivity was achieved for the thiol‐ene additions under templated conditions and Et3B/O2 radical initiation. After enantiomer separation (chiral stationary phase HPLC), aqueous conditions provoked aggregation. Detailed structural evolution was afforded by ECD/CPL monitoring. Three regimes can be observed and characterized by strong modifications in chiroptical patterns under, at, or above a 70 % H2O : THF threshold. In luminescence, high glum dissymmetry factors values were obtained, up to 0.022, as well as a double sign inversion of CPL signals during the aggregation, a behavior rationalized by time‐dependent density functional theory (TDDFT) calculations. Langmuir layers of enantiopure disulfide macrocycles were formed at the air–water interface and transferred onto solid substrates to afford Langmuir–Blodgett films, which were then studied by AFM and UV/ECD/fluorescence/CPL. [ABSTRACT FROM AUTHOR]

Abstract: A mild and practical Barbier–Negishi coupling of secondary alkyl bromides with aryl and alkenyl triflates and nonaflates has been developed. This challenging reaction was enabled by the use of a very bulky imidazole‐based phosphine ligand, which resulted in good yields as well as good chemo‐ and site selectivities for a broad range of substrates at room temperature and under non‐aqueous conditions. This reaction was extended to primary alkyl bromides by using an analogous pyrazole‐based ligand. [ABSTRACT FROM AUTHOR]

A phase-transfer-catalyzed asymmetric Michael addition of (iminomethyl)phosphonates to α,β-unsaturated ketones is described. In the presence of 1 mol-% of a chiral dinuclear N-spiro ammonium salt, the addition reaction proceeded smoothly to afford the adducts in up to 97 % yield with up to 99:1 dr and 78 % ee. One of the products was readily converted into a cyclic α-aminophosphonic acid derivative without any erosion of the enantiopurity. [ABSTRACT FROM AUTHOR]

Hydrocarbons are still the most important precursors of functionalized organic molecules, which has stirred interest in the discovery of new C−H bond functionalization methods. We describe herein a new step-economical approach that enables C−C bonds to be constructed at the terminal position of linear alkanes. First, we show that secondary alkyl bromides can undergo in situ conversion into alkyl zinc bromides and regioconvergent Negishi coupling with aryl or alkenyl triflates. The use of a suitable phosphine ligand favoring Pd migration enabled the selective formation of the linear cross-coupling product. Subsequently, mixtures of secondary alkyl bromides were prepared from linear alkanes by standard bromination, and regioconvergent cross-coupling then provided access to the corresponding linear arylation product in only two steps. [ABSTRACT FROM AUTHOR]

The simulation of water dynamics at the soil-root interface is of great importance to understand the processes of water and energy transfer, and availability of water to plants in the soil-plant-atmosphere continuum (SPAC) system. This review systematically summarizes various root water uptake models proposed since the 1960s for water dynamics in the SPAC system using macroscopic modeling approaches. Also, critical discussion, based on the review of the existing models, is given in relation to further improvement of root water uptake models and thus the enhancement of the simulation results. It stresses that more efforts should be directed in the key areas of using different modeling techniques such as the inverse, hybrid and water compensation methods, together with the quantification of root growth for the development and calibration of root water uptake models in the future. [ABSTRACT FROM AUTHOR]

An enantioselective aza-Friedel-Crafts (F-C) reaction of indoles with cyclic N-acylketimines has been developed. By using chiral phosphoric acid catalysts, a wide range of enantioenriched trifluoromethyldihydroquinazolines was obtained in excellent yields (up to 98%) with good to high enantioselectivities (up to 99% ee). [ABSTRACT FROM AUTHOR]

A CrFeO mixed oxide with an FeCr 2 O 4 spinel structure was treated with sulfuric acid and tested for catalytic combustion of dichloromethane (DCM). The acid-treated catalysts (denoted as CrFeO-4S and CrFeO-9S) were more active than the pristine one, with the CrFeO-9S giving a 2-fold higher rate at 240 °C (35.7 versus 17.8 μmol m−2 h−1). More importantly, the acid treatment greatly enhanced the catalyst stability in long term reaction. Various characterizations revealed that the acid treatment improved the redox property and surface acidity of the CrFeO oxide, which accounted for the enhance activity. Meanwhile, the acid treatment removed weakly coordinated Cr species on the catalyst surface and thus avoided the Cr leakage during the reaction, which was responsible for the excellent stability. Moreover, kinetics and spectroscopic results revealed that the surface sulfate evolved a new reaction path to the formation of formaldehyde intermediate, which could be further oxidized to CO x. [Display omitted] • The CrFeO catalyst contained a FeCr 2 O 4 spinel structure. • The H 2 SO 4 treatment on the CrFeO removed part of Cr species in the catalyst. • The acid- treated catalysts were more active and stable for CH 2 Cl 2 oxidation. • The enhanced reducibility and surface acidity accounted for the improved performance. [ABSTRACT FROM AUTHOR]

In this paper, we propose the non-linear Born–Infeld scalar field and canonical scalar field dark energy models with the potential $$\frac{\lambda }{4}( {\phi ^2 - \sigma ^2 })^2 + V_0$$ , which admits late time de Sitter attractor solution. The attractor solution corresponds to an equation of state ω_φ → − 1 and a cosmic density parameter Ω_φ → 1, which are important features for a dark energy model that can meet the current observations. dark energy; canonical scalar field, non-linear Born–Infeld type scalar field, attractor solution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pt/MFe 2 O 4 (M = Ni and Co) catalysts are active in CO oxidation and tolerant to H 2 O. • The MFe 2 O 4 oxides consisted of a mixture of spinel and inverse spinel composites. • CO chemisorption on the Pt/CoFe 2 O 4 is weaker compared to that on the Pt/Fe 2 O 3. • Activation of oxygen species is easier on the Pt/MFe 2 O 4 than on the Pt/MO x. • Kinetic study reveals that the reaction follows a Mars van Krevelen mechanism. Pt supported on CoFe 2 O 4 and NiFe 2 O 4 spinel oxides were much more active for low temperature CO oxidation compared to those supported on monometallic oxides (i.e. Co 3 O 4 , Fe 2 O 3 and NiO). The Pt/CoFe 2 O 4 catalyst gave the best performance, with a turnover frequency of 0.27 s−1 at 50 ℃, which was three times as high as that on the Pt/Fe 2 O 3. The interaction between Pt and the spinel oxide facilitated the activation of the oxygen species as evidenced by the H 2 temperature programmed reduction results, and weakened the adsorption strength of CO on the Pt atoms as revealed by the in situ diffuse reflectance infrared Fourier transform spectroscopy results and kinetic investigation. These facts accounted for the enhanced reactivity. Moreover, the catalysts exhibited excellent water tolerance, which maintained activity even under 10 vol.% water vapor in the feed stock. Therefore, these catalysts are promising for practical applications. [ABSTRACT FROM AUTHOR]

Highlights • TLR5 may play an important role in AS regulated by TNF-α. • RUNX3 may involve with AS by regulating CD8 T-cells and CD4 + T cells. • MCEMP1 may play a role in AS by regulating immune response. Abstract Ankylosing spondylitis (AS) is a common form of seronegative spondyloarthritis. We had identified differentially expressed genes (DEGs) in AS based on our previous RNA-sequencing results. Our study aimed to identify key genes in AS by integrated microarray analysis. In this present study, we identified 1328 DEGs between AS and normal control by using integrated analysis of two datasets derived from the Gene Expression Omnibus (GEO) database. Functional annotation of DEGs were performed. Pathways in cancer, Pancreatic cancer and Natural killer cell mediated cytotoxicity were significantly enriched pathways for DEGs. Based on the shared DEGs of AS in both integrated analysis and our previous RNA-sequencing results, we constructed the protein and protein interaction (PPI) network. BIRC2, MAPILC3A and MAGED1 were hub proteins. Validation of gene expression by qRT-PCR were performed and the results were consistent with our integrated analysis generally. Our finding provided new clues for understanding the mechanism of AS. [ABSTRACT FROM AUTHOR]

A correction to the article "Chiral Phosphoric Acid-Catalyzed Asymmetric Aza-Friedel-Crafts Reaction of Indoles with Cyclic N-Acylketimines: Enantioselective Synthesis of Trifluoromethyldihydroquinazolines" that was published in the 2013 issue is presented.

An enantioselective aza-Friedel-Crafts reaction of cyclic N-acylketimines with electron-rich arenes is developed. [ABSTRACT FROM AUTHOR]

So far, symmetry-breaking charge separation (SB-CS) has been observed with a limited number of chromophores and is usually inhibited by the formation of an excimer. We show here that thanks to fine-tuning of the interchromophore coupling via structural control, SB-CS can be operative with pyrene, despite its high propensity to form an excimer. This is realized with a bichromophoric system consisting of two pyrenes attached to a crown ether macrocycle, which can bind cations of different sizes. By combining stationary and time-resolved spectroscopy together with molecular dynamics simulations, we demonstrate that the excited-state dynamics can be totally changed depending on the binding cation. Whereas strong coupling leads to rapid excimer formation, too weak coupling results in noninteracting chromophores. However, intermediate coupling, achieved upon binding of Mg 2+ , allows for SB-CS to be operative.

Aim: To verify that the T stage has greater weight than the N stage in the staging of colorectal cancer., Methods: Open data from the Surveillance, Epidemiology, and End Results program were reviewed and analyzed according to the T stage, N stage, and patients' observed survival (OS). The relative weights of the T and N stages were calculated by multiple linear regressions based on their impact on survival. Risk scores for 25 TN categories were then calculated from the T and N stage relative weights, and a rearranged tumor node metastasis (TNM) staging system was proposed via a cluster analysis of the TN scores., Results: Both T and N stages significantly affect the OS of patients with colorectal cancer. Moreover, the T stage has greater weight than the N stage in the TNM staging system of colorectal cancer. For colon cancer, the relative T and N stage weights were 0.58 and 0.42, respectively, and for rectal cancer, the relative T and N stage weights were 0.61 and 0.39, respectively. On the basis of cluster analysis of the TN scores, T1N1a was classified to stage I, and T2N1a-1b and T1N1b-2a were classified to stage II in our revised TNM staging system for both colon and rectal cancer. For colon cancer, T4bN0 was classified to stage IIIa, but for rectal cancer, it was classified to stage IIIb., Conclusion: As the T stage affects colorectal cancer survival more significantly than the N stage, the TNM staging should be revised by relative T stage weight.