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The anomalous Hall effect (AHE) that associated with the Berry curvature of occupied electronic states in momentum‐space is one of the intriguing aspects in condensed matter physics, and provides an alternative for potential applications in topological electronics. Previous experiments reported the tunable Berry curvature and the resulting magnetization switching process in the AHE based on strain engineering or chemical doping. However, the AHE modulation by these strategies are usually irreversible, making it difficult to realize switchable control of the AHE and the resultant spintronic applications. Here, we demonstrated the switchable control of the Berry‐curvature‐related AHE by electrical gating in itinerant ferromagnetic Cr7Te8 with excellent ambient stability. The gate‐tunable sign reversal of the AHE can be attributed to the redistribution of the Berry curvature in the band structure of Cr7Te8 due to the intercalation‐induced change in the Fermi level. Our work facilitates the applications of magnetic switchable devices based on gate‐tunable Berry curvature. [ABSTRACT FROM AUTHOR]

An efficient rhodium(III)‐catalysed C−H activation of 3‐aryl‐1‐H‐indazoles with easily available vinylethylene carbonate has been reported. A series of allyl alcohol substituted 3‐aryl‐1‐H‐indazoles were obtained with broad functional groups tolerance and favourable stereoselectivity. Notably, C−H and C−O bonds were selectively activated in "one pot" manner, releasing CO2 as the sole by‐product and avoiding external oxidant. This protocol provides a powerful approach for the post stage C−H allylation of indazole‐based substrates. [ABSTRACT FROM AUTHOR]

Dielectric microspheres naturally possess unique optical properties by which the light's focus and confinement can be manipulated on a microscale. Combining microspheres and optical or Raman microscopy, super‐resolution imaging beyond the diffraction limit and enhancement of Raman signals are demonstrated to provide abundant spectroscopic information on materials. However, microsphere‐aided super‐resolution scanning photocurrent imaging remains challenging to date. Here, based on the photonic nanojet mechanism, a super‐resolution photocurrent and spectral microscopy equipped with a scanning tip with silica dielectric microspheres are presented. With such microsphere‐aided microscopy, order of magnitude enhancements for single‐point Raman and photoluminescence signals can be achieved, and the spatial resolutions for photocurrent and spectral mapping surpass the best resolution of the original confocal system restricted by the diffraction limit. This versatile system enables correlative super‐resolution spectral and photocurrent imaging, serving as a reliable tool for comprehensively understanding and uncovering the optoelectronic properties of materials. [ABSTRACT FROM AUTHOR]

A highly efficient strategy to construct benzo[d][1,3]diazepines via selective C−H bond activation of N‐aryl amidines and coupling with alkynyl cyclobutyl acetates was achieved successfully by RuII‐catalyzed [5+2] cyclization. This protocol features excellent regioselectivity, wide substrate tolerance, mild reaction conditions, which might be potentially applied in the discovery of lead compounds for the developing new drugs. [ABSTRACT FROM AUTHOR]

To investigate the dynamic mechanical behaviors of c‐plane and a‐plane sapphire, a novel anisotropic constitutive model and fracture criterion are constructed on the basis of bond‐based peridynamics (BB‐PD) theory. And the concept of strain is introduced in the framework of BB‐PD. After that, the simulations of a‐ and c‐planes of sapphire under spherical and cylindrical impact are conducted. In addition to capturing the distribution of strain and damage, the histories of various fracture types such as the primary fracture front and cracks are monitored for quantitative analysis. The numerical predictions are shown to agree well with previous experimental results, and further reveal the damage and failure mechanisms of sapphire. The different forms of contact between the projectile and the target strongly influence the stress waves generated and energy transferred ultimately affecting the damage development process. The crystal orientation dominates the appearance of anisotropic crack modes. Crack bending and deflection, as well as spalling‐like fracture, are associated with wave reflection and intersection. Moreover, an in‐depth examination of the observed wave splitting phenomenon is performed. [ABSTRACT FROM AUTHOR]

Magnetic tunnel junctions (MTJs), a prominent type of spintronic device based on the spin valve effect, have facilitated the development of numerous spintronic applications. The technical appeal for the next‐generation MTJ devices has been proposed in two directions: improving device performance by utilizing advanced two‐dimensional (2D) ferromagnetic materials or extending device functionalities by exploring the gate‐tunable magnetic properties of ferromagnets. Based on the recent development of 2D magnets with the ease of external stimuli, such as electric field, due to their reduced dimensions, reliable prospects for gate‐tunable MTJ devices can be achieved, shedding light on the great potential of next‐generation MTJs with multiple functionalities for various application environments. While the electrical gate‐tunable MTJ device is highly desirable for practical spintronic devices, it has not yet been demonstrated. Here, we demonstrate the experimental realization of a spin valve device by combining a vertical Fe3GeTe2/h‐BN/Fe3GeTe2 MTJ with an electrolyte gate. The magnetoresistance ratio (MR ratio) of 36% for the intrinsic MTJ confirms the good performance of the device. By electrolyte gating, the tunneling MR ratio of Fe3GeTe2/h‐BN/Fe3GeTe2 MTJ can be elevated 2.5 times, from 26% to 65%. Importantly, the magnetic fields at which the magnetoresistance switches for the MTJ can be modulated by electrical gating, providing a promising method to control the magnetization configuration of the MTJ. Our work demonstrates a gate‐tunable MTJ device toward the possibility for gate‐controlled spintronic devices, paving the way for performing 2D magnetism manipulations and exploring innovative spintronic applications. [ABSTRACT FROM AUTHOR]

Summary: The widespread application of isoproturon (IPU) can cause serious pollution to the environment and threaten ecological functions. In this study, the IPU bacterial N‐demethylase gene pdmAB was transferred and expressed in the chloroplast of soybean (Glycine max L. 'Zhonghuang13'). The transgenic soybeans exhibited significant tolerance to IPU and demethylated IPU to a less phytotoxic metabolite 3‐(4‐isopropylphenyl)‐1‐methylurea (MDIPU) in vivo. The transgenic soybeans removed 98% and 84% IPU from water and soil within 5 and 14 days, respectively, while accumulating less IPU in plant tissues compared with the wild‐type (WT). Under IPU stress, transgenic soybeans showed a higher symbiotic nitrogen fixation performance (with higher total nodule biomass and nitrogenase activity) and a more stable rhizosphere bacterial community than the WT. This study developed a transgenic (TS) soybean capable of efficiently removing IPU from its growing environment and recovering a high‐symbiotic nitrogen fixation capacity under IPU stress, and provides new insights into the interactions between rhizosphere microorganisms and TS legumes under herbicide stress. [ABSTRACT FROM AUTHOR]

2D twisted layered materials provide a new platform to study strongly correlated quantum phenomena. In homo‐ or heterostructures, the interlayer coupling is sensitive to the twist angles (θ), which serves as a key order parameter to controllably adjust exotic properties therein. The widely studied atomically thin molybdenum disulfide (MoS2) shows strong photoluminescence (PL) and is considered a promising optoelectronic material. Herein, by applying a uniaxial strain up to 5%, the evolution of the Raman and PL spectra of bilayer MoS2 with four different twist angles is investigated. The redshift per unit strain of the PL energy in twisted bilayer MoS2 (tBLM) reaches its extreme when θ is 30°. Further, two kinds of phototransistors based on tBLM structures with twist angles of 0° and 30° are constructed. The photoresponsivity (R) and the specific photodetectivity (D*) of the 30°‐twisted‐tBLM‐based phototransistor are successfully improved by ≈20 and ≈100 times than those values of the 0°‐twisted one, respectively. These findings provide a beneficial understanding of the effects of twist angle and strain on the optical and electrical applications based on tBLM and are applicable to other 2D materials. [ABSTRACT FROM AUTHOR]

Background: Patients with refractory central nervous system leukemia (CNSL) have a dismal prognosis and lack effective therapy. Case reports have shown that sorafenib is effective against brain metastases, including leukemia. Methods: To explore the efficacy of sorafenib combined with conventional therapies for refractory CNSL, a phase 2 study was conducted. The primary end point was the complete remission rate (CRR) within 8 weeks of treatment. Secondary end points included the overall response rate (ORR), event‐free survival (EFS), overall survival (OS), and adverse events (AEs). Results: Twenty‐six patients with refractory CNSL were enrolled; they included 17 with isolated CNSL, 7 with hematological relapse, and 2 with another extramedullary relapse. After 8 weeks of treatment, 21 patients achieved complete remission, 2 achieved partial remission, and 3 achieved no remission for a CRR of 80.8% (95% CI, 62.1%‐91.5%) and an ORR of 88.5% (95% CI, 71.0%‐96.0%). Twenty patients survived, and 6 died. The 2‐year EFS and OS rates were 75.0% (95% CI, 54.5%‐88.3%) and 76.9% (95% CI, 54.2%‐90.4%), respectively. Six patients experienced grade 3 or 4 treatment‐related AEs, including moderate chronic graft‐vs‐host disease (n = 3), grade 3 or 4 acute graft‐vs‐host disease (n = 2), and grade 3 skin rash (n = 1). No treatment‐related deaths occurred during the therapy of refractory CNSL. Conclusions: Sorafenib combined with conventional therapies is effective and safe for refractory CNSL. Lay Summary: Sorafenib combined with conventional therapies is effective and safe for refractory central nervous system leukemia. Sorafenib combined with conventional therapies is effective and safe for refractory central nervous system leukemia. [ABSTRACT FROM AUTHOR]

Summary: The (R)‐ and (S)‐enantiomers of the chiral herbicide napropamide (NAP) show different biological activities and ecotoxicities. These two enantiomers behave differently in the environment due to enantioselective catabolism by microorganisms. However, the molecular mechanisms underlying this enantioselective catabolism remain largely unknown. In this study, the genes (snaH and snpd) involved in the catabolism of NAP were cloned from Sphingobium sp. B2, which was capable of catabolizing both NAP enantiomers. Compared with (R)‐NAP, (S)‐NAP was much more rapidly transformed by the amidase SnaH, which initially cleaved the amide bonds of (S)/(R)‐NAP to form (S)/(R)‐2‐(1‐naphthalenyloxy)‐propanoic acid [(S)/(R)‐NP] and diethylamine. The α‐ketoglutarate‐dependent dioxygenase Snpd, showing strict stereoselectivity for (S)‐NP, further transformed (S)‐NP to 1‐naphthol and pyruvate. Molecular docking and site‐directed mutagenesis analyses revealed that when the (S)‐enantiomers of NAP and NP occupied the active sites, the distance between the ligand molecule and the coordination atom was shorter than that when the (R)‐enantiomers occupied the active sites, which facilitated formation of the transition state complex. This study enhances our understanding of the preferential catabolism of the (S)‐enantiomer of NAP on the molecular level. [ABSTRACT FROM AUTHOR]

Recently, it was reported that long non‐coding RNAs (lncRNAs) participated in promoting hepatocellular carcinoma (HCC) initiation and progression. Herein, we reported that the expression level of LINC01287 was elevated in HCC cell lines and tissues. LINC01287 down‐regulation inhibited HCC cells growth and invasion both in vitro and in vivo. LINC01287 exerted as a ceRNA and negatively regulated miR‐298 expression. MYB was identified as a downstream target of miR‐298. The miR‐298/MYB axis mediated LINC01287's effect on HCC. To the best of our knowledge, our findings provided the first evidence that LINC01287 functioned as an oncogene in HCC. LINC01287 may be a candidate prognostic biomarker and a target for new therapies in HCC patients. [ABSTRACT FROM AUTHOR]

Quick response (QR) code, one of the two‐dimensional barcodes, is now being widely used in all fields. The effectiveness of decoding, however, needs to be improved in real‐time application. In most cases, the decoding procedure is time consuming, in which the detection of QR code plays an essential part. Therefore, this study proposes a fast detection method of QR code based on run‐length coding: firstly, a novel approach is proposed to detect the minimum region containing position detection pattern (PDP) in QR code. Second, coordinates of central PDP in QR code are calculated by using run‐length coding. The highlight in this step is the calculation, which utilises modified Knuth–Morris–Pratt algorithm. By this means, the computational complexity can be reduced tremendously. Finally, QR code can be detected successfully with the coordinates. The experimental results show that the proposed method is time saving and suitable for real‐time application. [ABSTRACT FROM AUTHOR]

The worldwide use of the phenylurea herbicide, isoproturon (IPU), has resulted in considerable concern about its environmental fate. Although many microbial metabolites of IPU are known and IPU-mineralizing bacteria have been isolated, the molecular mechanism of IPU catabolism has not been elucidated yet. In this study, complete genes that encode the conserved IPU catabolic pathway were revealed, based on comparative analysis of the genomes of three IPU-mineralizing sphingomonads and subsequent experimental validation. The complete genes included a novel hydrolase gene ddhA, which is responsible for the cleavage of the urea side chain of the IPU demethylated products; a distinct aniline dioxygenase gene cluster adoQTA1A2BR, which has a broad substrate range; and an inducible catechol meta-cleavage pathway gene cluster adoXEGKLIJC. Furthermore, the initial mono- N-demethylation genes pdmAB were further confirmed to be involved in the successive N-demethylation of the IPU mono- N-demethylated product. These IPU-catabolic genes were organized into four transcription units and distributed on three plasmids. They were flanked by multiple mobile genetic elements and highly conserved among IPU-mineralizing sphingomonads. The elucidation of the molecular mechanism of IPU catabolism will enhance our understanding of the microbial mineralization of IPU and provide insights into the evolutionary scenario of the conserved IPU-catabolic pathway. [ABSTRACT FROM AUTHOR]

ABSTRACT Anthocyanin is one of the flavonoid phytopigments with specific health benefits. The interaction between delphinidin-3- O-glucoside (D3G) and bovine serum albumin (BSA) was investigated by fluorescence spectroscopy, synchronous fluorescence spectroscopy, three-dimensional fluorescence spectroscopy, ultraviolet-visible absorption spectroscopy, circular dichroism spectroscopy and molecular modeling. D3G effectively quenched the intrinsic fluorescence of BSA via static quenching. The number of binding sites and binding constant Ka were determined, and the hydrogen bonds and van der Waals forces played major roles in stabilizing the D3G-BSA complex. The distance r between donor and acceptor was obtained as 2.81 nm according to Förster's theory. In addition, the effects of pH and metal ions on the binding constants were discussed. The results studied by synchronous fluorescence, three-dimensional fluorescence and circular dichroism experiments indicated that the secondary structures of the protein has been changed by the addition of D3G and the α-helix content of BSA decreased (from 56.1% to 52.4%). Furthermore, the study of site marker competitive experiments and molecular modeling indicated that D3G could bind to site I of BSA, which was in the large hydrophobic cavity of subdomain IIA. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Key points The companion paper provided evidence for basolateral anion exchange during cAMP stimulation of chloride and fluid secretion by Calu-3 monolayers; however, the molecular basis of this transport was not identified., To test the role of AE2, an anion exchanger expressed at the basolateral membrane of Calu-3 and many other epithelial cells, we used lentivirus-mediated RNA interference to generate a stable Calu-3 AE2 knock-down cell line and characterized its fluid and anion transport properties., AE2 knock-down suppressed fluid secretion and increased the fraction of cAMP-stimulated anion secretion that was sensitive to bumetanide inhibition., Basolateral Cl−/HCO3− exchange was nearly abolished in AE2 knock-down cells., We conclude that AE2 is active during forskolin-stimulated fluid secretion and mediates chloride uptake and bicarbonate recycling at the basolateral membrane., Abstract Anion exchanger type 2 (AE2 or SLC4A2) is an electroneutral Cl−/HCO3− exchanger expressed at the basolateral membrane of many epithelia. It is thought to participate in fluid secretion by airway epithelia. However, the role of AE2 in fluid secretion remains uncertain, due to the lack of specific pharmacological inhibitors, and because it is electrically silent and therefore does not contribute directly to short-circuit current ( Isc). We have studied the role of AE2 in Cl− and fluid secretion by the airway epithelial cell line Calu-3. After confirming expression of its mRNA and protein, a knock-down cell line called AE2-KD was generated by lentivirus-mediated RNA interference in which AE2 mRNA and protein levels were reduced ≥90%. Suppressing AE2 increased the expression of the cystic fibrosis transmembrane conductance regulator (CFTR) by ∼70% without affecting the levels of NKCC1 (Na+-K+-2Cl− cotransporter) or NBCe1 (Na+-nHCO3− cotransporter). cAMP agonists stimulated fluid secretion by parental Calu-3 and scrambled shRNA cells >6.5-fold. In AE2-KD cells this response was reduced by ∼70%, and the secreted fluid exhibited elevated pH and [HCO3−] as compared with the control lines. Unstimulated equivalent short-circuit current ( Ieq) was elevated in AE2-KD cells, but the incremental response to forskolin was unaffected. The modest bumetanide-induced reductions in both Ieq and fluid secretion were more pronounced in AE2-KD cells. Basolateral Cl−/HCO3− exchange measured by basolateral pH-stat in cells with permeabilized apical membranes was abolished in AE2-KD monolayers, and the intracellular alkalinization resulting from basolateral Cl− removal was reduced by ∼80% in AE2-KD cells. These results identify AE2 as a major pathway for basolateral Cl− loading during cAMP-stimulated secretion of Cl− and fluid by Calu-3 cells, and help explain the large bumetanide-insensitive component of fluid secretion reported previously in airway submucosal glands and some other epithelia. [ABSTRACT FROM AUTHOR]

Key points The mechanisms of anion and fluid transport by airway submucosal glands are not well understood and may differ from those in surface epithelium., The Calu-3 cell line is often used as a model for submucosal gland serous cells and has cAMP-stimulated fluid secretion; however, it does not actively transport chloride under short-circuit conditions., In this study we show that fluid secretion requires chloride, bicarbonate and sodium, that chloride is the predominant anion in Calu-3 secretions, and that a large fraction of the basolateral chloride loading during cAMP stimulation occurs by Cl−/HCO3− exchange., The results suggest a novel cellular model for anion and fluid secretion by Calu-3 and submucosal gland acinar cells, Abstract Anion and fluid secretion are both defective in cystic fibrosis (CF); however, the transport mechanisms are not well understood. In this study, Cl− and HCO3− secretion was measured using genetically matched CF transmembrane conductance regulator (CFTR)-deficient and CFTR-expressing cell lines derived from the human airway epithelial cell line Calu-3. Forskolin stimulated the short-circuit current ( Isc) across voltage-clamped monolayers, and also increased the equivalent short-circuit current ( Ieq) calculated under open-circuit conditions. Isc was equivalent to the HCO3− net flux measured using the pH-stat technique, whereas Ieq was the sum of the Cl− and HCO3− net fluxes. Ieq and HCO3− fluxes were increased by bafilomycin and ZnCl2, suggesting that some secreted HCO3− is neutralized by parallel electrogenic H+ secretion. Ieq and fluid secretion were dependent on the presence of both Na+ and HCO3−. The carbonic anhydrase inhibitor acetazolamide abolished forskolin stimulation of Ieq and HCO3− secretion, suggesting that HCO3− transport under these conditions requires catalysed synthesis of carbonic acid. Cl− was the predominant anion in secretions under all conditions studied and thus drives most of the fluid transport. Nevertheless, 50-70% of Cl− and fluid transport was bumetanide-insensitive, suggesting basolateral Cl− loading by a sodium-potassium-chloride cotransporter 1 (NKCC1)-independent mechanism. Imposing a transepithelial HCO3− gradient across basolaterally permeabilized Calu-3 cells sustained a forskolin-stimulated current, which was sensitive to CFTR inhibitors and drastically reduced in CFTR-deficient cells. Net HCO3− secretion was increased by bilateral Cl− removal and therefore did not require apical Cl−/HCO3− exchange. The results suggest a model in which most HCO3− is recycled basolaterally by exchange with Cl−, and the resulting HCO3−-dependent Cl− transport provides an osmotic driving force for fluid secretion. [ABSTRACT FROM AUTHOR]

The electron pairing mechanisms in topological superconductors are pivotal for understanding the emergent topology‐related quantum states and play key roles in condensed matter physics. Theoretically, the quantization of magnetic flux in nano‐hole arrays within topological superconductors can be studied for understanding the Bogoliubov quasiparticles via the Little–Parks oscillation. However, experimental evidence of the quasiparticle states in such structures of topological superconductors remains elusive. Here, the unconventional superconducting quantum oscillation phenomena of the proximity‐induced 2D topological superconductivity (TSC) is demonstrated in a nano‐hole array of WTe2/NbSe2 heterojunction. The unconventional oscillation period in WTe2 is substantially smaller than that in the s‐wave superconductor NbSe2 (corresponds to Cooper pairs), implying the probable presence of novel quasiparticle states associated with TSC. Interestingly, such phenomena of multi‐charge flux quanta might be related to the multi‐particle bound states of TSC. These observations provide a new approach for exploring the unconventional superconducting quantum states in topological superconductors. [ABSTRACT FROM AUTHOR]