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Out‐of‐plane polarization is a highly desired property of two‐dimensional (2D) ferroelectrics for application in vertical sandwich‐type photoferroelectric devices, especially in ultrathin ferroelectronic devices. Nevertheless, despite great advances that have been made in recent years, out‐of‐plane polarization remains unrealized in the 2D hybrid double perovskite ferroelectric family. Here, from our previous work 2D hybrid double perovskite HQERN ((S3HQ)4EuRb(NO3)8, S3HQ=S‐3‐hydroxylquinuclidinium), we designed a molecular strategy of F‐substitution on organic component to successfully obtain FQERN ((S3FQ)4EuRb(NO3)8, S3FQ=S‐3‐fluoroquinuclidinium) showing circularly polarized luminescence (CPL) response. Remarkably, compared to the monopolar axis ferroelectric HQERN, FQERN not only shows multiferroicity with the coexistence of multipolar axis ferroelectricity and ferroelasticity but also realizes out‐of‐plane ferroelectric polarization and a dramatic enhancement of Curie temperature of 94 K. This is mainly due to the introduction of F‐substituted organic cations, which leads to a change in orientation and a reduction in crystal lattice void occupancy. Our study demonstrates that F‐substitution is an efficient strategy to realize and optimize ferroelectric functional characteristics, giving more possibility of 2D ferroelectric materials for applications in micro‐nano optoelectronic devices. [ABSTRACT FROM AUTHOR]

SUMMARY: Erianin, crepidatin, and chrysotobibenzyl are typical medicinal polymethoxylated bibenzyls (PMBs) that are commercially produced in Dendrobium species. PMBs' chemo‐diversity is mediated by the manifold combinations of O‐methylation and hydroxylation in a definite order, which remains unsolved. To unequivocally elucidate the methylation mechanism of PMBs, 15 possible intermediates in the biosynthetic pathway of PMBs were chemically synthesized. DcOMT1–5 were highly expressed in tissues where PMBs were biosynthesized, and their expression patterns were well‐correlated with the accumulation profiles of PMBs. Moreover, cell‐free orthogonal tests based on the synthesized intermediates further confirmed that DcOMT1‐5 exhibited distinct substrate preferences and displayed hydroxyl‐group regiospecificity during the sequential methylation process. The stepwise methylation of PMBs was discovered from SAM to dihydro‐piceatannol (P) in the following order: P → 3‐MeP → 4‐OH‐3‐MeP → 4‐OH‐3,5‐diMeP → 3,3'(4′),5‐triMeP → 3,4,4′,5‐tetraMeP (erianin) or 3,3′,4,5‐tetraMeP (crepidatin) → 3,3′,4,4′,5‐pentaMeP (chrysotobibenzyl). Furthermore, the regioselectivities of DcOMTs were investigated by ligand docking analyses which corresponded precisely with the catalytic activities. In summary, the findings shed light on the sequential catalytic mechanisms of PMB biosynthesis and provide a comprehensive PMB biosynthetic network in D. catenatum. The knowledge gained from this study may also contribute to the development of plant‐based medicinal applications and the production of high‐value PMBs. [ABSTRACT FROM AUTHOR]

Summary: Soybean is a short‐day plant that typically flowers earlier when exposed to short‐day conditions. However, the identification of genes associated with earlier flowering time but without a yield penalty is rare. In this study, we conducted genome‐wide association studies (GWAS) using two re‐sequencing datasets that included 113 wild soybeans (G. soja) and 1192 cultivated soybeans (G. max), respectively, and simultaneously identified a candidate flowering gene, qFT13‐3, which encodes a protein homologous to the pseudo‐response regulator (PRR) transcription factor. We identified four major haplotypes of qFT13‐3 in the natural population, with haplotype H4 (qFT13‐3H4) being lost during domestication, while qFT13‐3H1 underwent natural and artificial selection, increasing in proportion from 4.5% in G. soja to 43.8% in landrace and to 81.9% in improve cultivars. Notably, most cultivars harbouring qFT13‐3H1 were located in high‐latitude regions. Knockout of qFT13‐3 accelerated flowering and maturity time under long‐day conditions, indicating that qFT13‐3 functions as a flowering inhibitor. Our results also showed that qFT13‐3 directly downregulates the expression of GmELF3b‐2 which is a component of the circadian clock evening complex. Field trials revealed that the qft13‐3 mutants shorten the maturity period by 11 days without a concomitant penalty on yield. Collectively, qFT13‐3 can be utilized for the breeding of high‐yield cultivars with a short maturity time suitable for high latitudes. [ABSTRACT FROM AUTHOR]

With increasing concerns about noise pollution, the pursuit of highly dependable piezoelectric acoustic sensors for real‐time noise monitoring has come to the forefront of scientific research. Lead‐based perovskite piezoelectric films, exemplified by lead zirconate titanate Pb(Zr,Ti)O3 (PZT), surpass traditional piezoelectric materials such as ZnO and AlN in their piezoelectric properties, promising substantial advancements in next‐generation acoustic sensor technologies. However, the toxic nature of lead in PZT materials poses formidable environmental and human health risks. In an unprecedented breakthrough, it presents the pioneering development of an environmentally benign lead‐free piezoelectric Micro‐Electro‐Mechanical System (MEMS) acoustic sensor based on potassium sodium niobate (K,Na)NbO3 (KNN) film. High‐quality <001> textured 3 µm‐thick KNN film is successfully integrated into commercially used Si substrate, rendering exceptional piezoelectricity (transverse piezoelectric coefficients e31* of ≈8.5 C m−2) with satisfactory thermal stability. The atomic‐scale Z‐contrast imaging and piezoresponse force microscopy characterizations reveal that the outstanding piezoresponse originates from the local coexistence of multiple phases and the enhancement of extrinsic piezoelectric contributions from in‐plane polarization anisotropy. Finite element simulation is employed to design the triangular cantilever structure and annular diaphragm structure, each corresponding to different operating bandwidths. The resultant MEMS acoustic sensors stand out with outstanding acoustic performance (the high sensitivity and expansive receiving field of view), which are attributed to the microstructural engineering at multi‐length scales for the excellent piezoelectric properties of KNN film. These features enable sensitive acoustic monitoring in various environments, including large‐scale power grids and urban traffic. [ABSTRACT FROM AUTHOR]

The Dujiangyan Irrigation Project, a globally well‐known hydraulic engineering project, is significant for the Chengdu Plain. In recent years, due to water supply scarcity in the Chengdu Plain and increasing flood disasters in the Min River, the Moertan Reservoir was constructed to alleviate these pressures. The construction resulted in a mid‐reach embankment along the Min River that forced channel narrowing and triggered changes in channel morphology, flow and bedload transport. This study utilised field measurements coupled with physical and numerical models to simulate the resulting characteristics of flow, bedload transport and topographic change for different flood frequencies in the Dujiangyan reach following emplacement of the Moertan Reservoir. The results indicated that following extensive hydraulic regulation, the flow‐bedload transport characteristics and morphodynamics exhibited similar behaviours across different flood frequencies. The presence of a mid‐channel gravel‐cobble shoal (GCS) divided the flow into multiple branches, with the right branch systematically dominating flow and bedload transport across all flood frequencies. Further downstream, the Fish Mouth Levee effectively diverted nearly equal amounts of flow through the Inner and Outer rivers. In contrast, approximately 20% and 80% of the bedload was transported through the Inner and Outer rivers, respectively. The findings were beneficial in providing a reference for the flood season management of the Dujiangyan Irrigation Project and the maintenance of associated hydraulic engineering projects. [ABSTRACT FROM AUTHOR]

Significant progress has been made in tumor immunotherapy that uses the human immune response to kill and remove tumor cells. However, overreactive immune response could lead to various autoimmune diseases and acute rejection. Accurate and specific monitoring of immune responses in these processes could help select appropriate therapies and regimens for the patient and could reduce the risk of side effects. Granzyme B (GzmB) is an ideal biomarker for immune response, and its peptide substrate could be coupled with fluorescent dyes or contrast agents for the synthesis of imaging probes activated by GzmB. These small molecules and nanoprobes based on PET, bioluminescence imaging, or fluorescence imaging have proved to be highly GzmB specific and accuracy. This review summarizes the design of different GzmB‐responsive imaging probes and their applications in monitoring of tumor immunotherapy and overreactive immune response. This article is categorized under:Diagnostic Tools > In Vivo Nanodiagnostics and Imaging [ABSTRACT FROM AUTHOR]

To providing evidence‐based recommendations for surgery in patients with femoral neck fractures, a meta‐analysis was conducted to comprehensively evaluate the effects of cemented and uncemented prostheses on postoperative surgical site wound infection and pain in these patients. Relevant studies on the use of cemented prostheses in femoral neck fractures were retrieved from PubMed, EMBASE, Cochrane Library, Ovid, CNKI, and Wanfang databases from the time of their establishment until March 2023. Two authors independently screened and extracted data from the included and excluded literature according to predetermined criteria. Review Manager 5.4 software was used to perform meta‐analyses on the collected data. A total of 27 articles comprising 34 210 patients (24 646 cases in the cemented group and 9564 cases in the uncemented group) were included in the final analysis. The results of the meta‐analysis showed that, compared with the uncemented group, cemented prostheses significantly reduced the incidence of surgical site wound infections (odds ratio [OR]: 0.75, 95% confidence interval [CI]: 0.64–0.88, p < 0.001) and relieved surgical site wound pain (standardised mean difference: −0.76, 95% CI: −1.12–0.40, p < 0.001), but did not reduce the incidence of pressure ulcers after surgery (OR: 0.50, 95% CI: 0.20–1.26, p = 0.140). Therefore, existing evidence suggests that the use of cemented prostheses in femoral neck fracture surgery can significantly reduce the incidence of surgical site wound infections and relieve surgical site wound pain, which is worthy of clinical recommendation. [ABSTRACT FROM AUTHOR]

Excess water pressure strongly affects the rheology and flow behaviour of debris flows, and the mechanisms for development and persistence of the pressure can be diverse. Using nine experimental slurries prepared with the sediments collected from the deposit of a large‐magnitude debris flow by modifying maximum grain size and solid concentration, the influence of agitation on excess water pressure is investigated with a cylinder apparatus, consisting of a coaxially mounted bucket and impeller driven by a variable‐speed motor. Agitation proceeding in three dynamic stages raises relative excess water pressure (R) by 17%–34% of the peak R in the static stage, showing that agitation can significantly increase excess water pressure. The magnitude of the steady R increases with the level of agitation, which is measured by impeller speed and slurry temperature, and the steady R in a slurry is agitation‐level‐dependent below its potential maximum value. The transfer of particle weight to water in debris flows can occur under zero or very low to extremely low effective stresses. Agitation raises excess water pressure essentially by promoting dispersion of the finest‐grained grains in water and that of progressively larger grains in gradually coarser‐grained slurries. The flow resistance of the tested slurries, characterized by net torque exerted on the impeller by the motor, decreases with increasing liquefaction ratio, demonstrating that agitation enhances debris‐flow mobility by raising excess water pressure. It is of importance to dampen agitation by building proper mitigation measures in remedial practices. [ABSTRACT FROM AUTHOR]

With the increased use of artificial light and the prolonged use of optoelectronic products, light damage (LD) to the human retina has been identified as a global vision‐threatening problem. While there is evidence of a significant correlation between light‐induced retinal damage and age‐related vision impairment in age‐related macular degeneration, it is unclear how light‐induced retinal degeneration manifests itself and whether there are agents capable of preventing the development of LD in the retina. This study investigated a mechanism by which blue light leads to photoreceptor death. By observing blue light exposure in retinal organoids and photoreceptor cells, we concluded that there could be significant apoptosis of the photoreceptors. We demonstrate that regenerating islet‐derived 1 alpha (REG1A) prevents photoreceptors from undergoing this LD‐induced apoptosis by increasing expression of the anti‐apoptotic gene Bcl2 and downregulating expression of the pro‐apoptotic gene Bax, resulting in reduced mitochondrial damage and improved aerobic capacity in photoreceptor cells. For the first time, REG1A has been shown to restore mitochondrial function and cell apoptosis after LD‐induced damage, suggesting its potential application in the prevention and treatment of retinal vision loss. [ABSTRACT FROM AUTHOR]

A rhodium‐catalyzed cascade migration‐annulation reaction of 1‐sulfonyl‐1,2,3‐triazole has been developed. As the key step, the 1,3‐sulfinate migration of α‐imino rhodium carbene yielded an extended zwitterion, which was intramolecularly trapped by aldehyde group furnishing bridged N,O‐heterocyclic 1,6‐epoxybenzo[c]azocine as the [5+2] cyclization product. This migration‐annulation strategy provides more flexibility for heterocycle synthesis and medium‐sized ring construction, especially for the construction of polycycles with complex skeletons. [ABSTRACT FROM AUTHOR]

A new ring‐opening method for pyridotriazole was developed. Geminal diiodo and dibromo methylpyridines were obtained in moderate to good yields when pyridotriazoles were treated with iodine and bromine under mild conditions. [ABSTRACT FROM AUTHOR]

Recent advances in perovskite ferroelectrics have fostered a host of exciting sensors and actuators. Defect engineering provides critical control of the performance of ferroelectric materials, especially lead‐free ones. However, it remains a challenge to quantitatively study the concentration of defects due to the complexity of measurement techniques. Here, a feasible approach to analyzing the A‐site defect and electron in alkali metal niobate is demonstrated. The theoretical relationships among defect concentration, conductivity, and oxygen partial pressure can be established based on the defect chemistry equilibria. The type and concentration of defects are reflected through the conductivity variation with oxygen partial pressure. As a result, the variation of defect concentration gives rise to defect‐driven interfacial polarization, which further leads to distinct properties of the ceramics. e.g. abnormal dielectric behavior. Furthermore, this study also suggests a strategy to manipulate defects and charges in perovskite oxides for performance optimization. [ABSTRACT FROM AUTHOR]

Cyclopropane, dihydropyrrole, and azepane ring systems were synthesized conveniently from sulfinate‐tethered triazoles. The divergent synthetic strategy started with the unique 1,3‐sulfinate migration of an α‐imino carbene. The efficient reaction allowed control of the zwitterion bearing multiple reactive sites depending on the increased stability of the resulting carbocation and anion. The sulfinate was converted to a sulfone after the group migration, and a stable anion bearing two electron‐withdrawing groups was thus formed. Catalytic amounts of iodide acted as a switch for the synthesis of cyclopropanes and dihydropyrroles. The reaction merits including readily available substrates, mild reaction conditions, and excellent functional group compatibility qualified this protocol a possible synthetic tool for cyclic compounds, especially for N‐heterocycles. [ABSTRACT FROM AUTHOR]

3‐Methylidene‐2,3‐dihydropyrroles with an ester or keto group at the C4 position were obtained in moderate to good yields from enamine‐tethered triazoles in the presence of a rhodium(II) catalyst. A formal 1,2‐enamine migration/cyclization cascade triggered by formation of an α‐amino carbene is proposed to illustrate the mechanism. The valuable exocyclic double bond showed distinctive reactivity, which is very useful for further introduction of functional groups. The dihydropyrrole is stable under neutral, weakly acidic, or weakly basic conditions. [ABSTRACT FROM AUTHOR]

With the goals of sustainable development adopted by more and more nations, the lead‐free trend of multilayer ceramic actuators has become a widely recognized consensus. Sintering in a reducing atmosphere is a necessary approach for preparing lead‐free ceramics co‐fired with low‐cost nickel internal electrodes. Herein, (1 − x)K0.48Na0.52Nb0.96Ta0.04O3–xSr(Zr0.5Ti0.5)O3 + 0.03ZrO2 + 0.08MnO2 (KNNT‐SZT) ceramics were sintered in a reducing atmosphere using a solid‐state reaction. The Sr(Zr0.5Ti0.5)O3 (SZT) dopant decreased the Curie temperature TC and the O–T phase transition temperature. The enhanced diffuseness of the ferroelectric phase transition of KNNT‐SZT ceramics is attributed to the element doping and the locally inhomogeneous microstructure. High inverse piezoelectric coefficients d33* of 883 and 787 pm/V were obtained for the 8‐ and 9‐mol% SZT‐doped samples, respectively. These results were attributed to the synergistic effect of ferroelectric domains with different sizes. The diffused O–T phase transition significantly improved the piezoelectric temperature stability of the 9‐mol% SZT‐doped sample, whose electric‐field‐induced strain decreased by <10% from room temperature (25°C) to 115°C. The cyclic fatigue test showed that >98% of the initial d33* was retained after 106 cycles of unipolar electrical loading. The KNNT‐SZT ceramics sintered in a reducing atmosphere possessed excellent inverse piezoelectric properties and are expected to be applied in the field of multilayer ceramic piezoelectric actuators with base metal internal electrodes. [ABSTRACT FROM AUTHOR]

Photocatalysis is regarded as a promising approach to solve the energy crisis by producing H2 from water splitting reaction driven by solar light. However, low photogenerated charge carriers yielding and separating rates limit the quantum efficiency in photocatalytic reactions, which is a common drawback for most visible‐light photocatalysts. Herein, a bismuth‐based photocatalyst, Bi4NbO8Br, through intercalating NbO6 octahedrons into layered BiOBr nanosheets, is designed and fabricated. Bi4NbO8Br demonstrates an enhanced photocatalytic water splitting ability as compared to BiOBr in visible light irradiation. The light absorption spectrum of Bi4NbO8Br is wider than that of BiOBr. It is found that such enhancements give rise to the ferroelectricity induced by the intercalated NbO6. The internal spontaneous polarization and an internal electric field formed in Bi4NbO8Br result in a significant band bending in its electronic structure and greatly promote the migration and separation of charge carriers in visible light irradiation. [ABSTRACT FROM AUTHOR]

Innovations in genomics have enabled the development of low‐cost, high‐resolution, single nucleotide polymorphism (SNP) genotyping arrays that accelerate breeding progress and support basic research in crop science. Here, we developed and validated the SoySNP618K array (618,888 SNPs) for the important crop soybean. The SNPs were selected from whole‐genome resequencing data containing 2,214 diverse soybean accessions; 29.34% of the SNPs mapped to genic regions representing 86.85% of the 56,044 annotated high‐confidence genes. Identity‐by‐state analyses of 318 soybeans revealed 17 redundant accessions, highlighting the potential of the SoySNP618K array in supporting gene bank management. The patterns of population stratification and genomic regions enriched through domestication were highly consistent with previous findings based on resequencing data, suggesting that the ascertainment bias in the SoySNP618K array was largely compensated for. Genome‐wide association mapping in combination with reported quantitative trait loci enabled fine‐mapping of genes known to influence flowering time, E2 and GmPRR3b, and of a new candidate gene, GmVIP5. Moreover, genomic prediction of flowering and maturity time in 502 recombinant inbred lines was highly accurate (>0.65). Thus, the SoySNP618K array is a valuable genomic tool that can be used to address many questions in applied breeding, germplasm management, and basic crop research. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides are attractive electrocatalysts for oxygen evolution reaction (OER) or hydrogen evolution reaction (HER) due to their natural abundance and diverse structure. Herein, nickel sulfides (Ni3S2) and nickel/cobalt sulfides nanohybrid have been in situ fabricated on nickel foam (NF) by a facile hydrothermal method with sodium sulfide (Ss), L‐cysteine (Lc) or thiourea (Tu) as a sulfur source, respectively. The results show that sulfur source has a great influence on the phase structure, morphology and electrocatalytic performance of transition metal sulfides. The nickel sulfide with the sodium sulfide as a sulfur source (NiSs) shows better HER and OER activity in 1 M KOH. With the Co‐doping, three‐dimensional honeycomb‐like NiCoSs nanosheet clusters exhibits the enhanced electrocatalysis properties with overpotentials of only 168 mV at 10 mA cm–2 for HER and 234 mV at 20 mA cm–2 for OER, respectively. The NiCoSs shows the good bifunctional activities for overall water splitting and presents considerable stability for 24 hours. The good electrochemical activities of metal sulfides by using inorganic sodium sulfide can be attributed to the large exposed surface area and heterostructure compositions of Co9S8 and Ni3S2. [ABSTRACT FROM AUTHOR]

Catalytic reduction of 4‐nitrophenol (4‐NP) to 4‐aminophenol (4‐AP) over high‐performance and stable metal nanoparticle catalyst is highly desirable. This study experimentally demonstrated that graphdiyne (GDY), an all‐carbon two‐dimensional material composed of two hybrid carbon atoms (sp and sp2), can uniformly disperse copper nanoparticles through simple microwave reduction and has excellent 4‐NP reduction ability. Cu/GDY shows an extraordinary reaction rate constant of 0.9984 min−1, Moreover, the catalytic activity is maintained almost intact within five cycles. These encouraging results demonstrated that the unique pores and electronic structure of GDY enhance the stability of anchored metal nanoparticles and have great potential to degrade 4‐NP as a promising support for copper nanoparticles. [ABSTRACT FROM AUTHOR]

Smart windows with adjustable transmittance via physical stimuli are eagerly desired for sorts of energy‐saving lighting systems. However, reciprocal trade‐off relationship such as high transparency and coloration/discoloration ability exists in smart windows, not conducive to optical‐electrical coupling and leap in performance. Substituting for common composites utilized in smart windows, here, single transparent ceramic‐based smart windows are reported through composition design and defect management strategies to regulate the optoelectronic performances and break off the contradictions between optical transmittance, photo‐thermochromism and electrical conductivity. By first principles calculations and precisely tuning Er3+, Ba2+, Sr2+ concentrations in non‐stoichiometric Er‐doped (K0.5Na0.5)NbO3‐(Ba, Sr)TiO3, the fabricated ceramics exhibit brilliant transparency and multi‐mode dramatical and reversible modulations of pellucidity, photoluminescence intensity, along with conductivity (over fivefold variation), enabling prominent optoelectronic information storage and modulating capacity in vivid potential applications, such as easy‐readout/erasable optical memorizers, photo‐memristors and anti‐counterfeiting displays. [ABSTRACT FROM AUTHOR]

Reactions of (NH4)2WS4 with CuCN, CuCN/1,2‐bis(4‐pyridyl)propane (bppa) or [Cu(MeCN)4]PF6/bppa under different reaction conditions afforded a set of two‐ or three‐dimensional W/Cu/S cluster‐based coordination polymers including {[Et4N]2[WS4Cu4(μ‐CN)2(μ‐I)2]}n (1), [WS4Cu4(μ‐CN)2(bppa)2]n (2) and {[WS4Cu4(bppa)4](PF6)2}n (3), respectively. Compound 2 can be readily formed from reaction of 1 with bppa under solvothermal conditions. Compounds 1 and 2 feature two‐dimensional networks with a "sql" topology, while 3 possesses a two‐fold interpenetrated three‐dimensional net with a rare "reo" topology. Compounds 1–3 in DMF exhibited different third‐order nonlinear optical responses, and they all showed a reverse saturable absorption while 2 held a strong self‐focusing effect. [ABSTRACT FROM AUTHOR]

Anthrathiadiazole is a key synthon for the construction of large azaacenes, however, the attachment of different substituents onto the skeleton of anthrathiadiazole is difficult but highly desirable because it could be easy to enrich the structures of azaacenes. Here, it is demonstrated that anthrathiadiazole derivatives with −Br, −CN, and −OCH3 groups could be easily constructed through a simple [4+2] cycloaddition reaction between a,a,a',a'‐tetrabromo‐o‐xylenes derivatives and benzo[c][1,2,5]thiadiazole‐4,7‐dione. The structures of the as‐prepared compounds with different substituents were carefully characterized. Moreover, the basic physical properties of the as‐prepared anthrathiadiazole derivatives were fully investigated, where the cyano‐substituted derivative (BTH‐CN) has the highest stability and the methoxy‐substituted derivative (BTH‐OCH3) is easy to be oxidized. Moreover, the two‐photon absorption (TPA) characteristics of different anthrathiadiazoles are also studied by using the femtosecond Z‐scan technique. The results show that the fused anthrathiadiazole skeletons possess large TPA cross‐section values δ2 in the range of 3000–5000 GM, where the nature, position and strength of the substituted groups have strong effect on these values. [ABSTRACT FROM AUTHOR]

An enantioselective synthetic approach for preparing manginoids and guignardones, two types of biogenetically related meroterpenoids, is reported. This bioinspired and divergent synthesis employs an oxidative 1,3‐dicarbonyl radical‐initiated cyclization and cyclodehydration of the common precursor to forge the central ring of the manginoids and guignardones, respectively, at a late stage. Key synthetic steps include silica‐gel‐promoted semipinacol rearrangement to form the 6‐oxabicyclo[3.2.1]octane skeleton and the Suzuki–Miyaura reaction of vinyl bromide to achieve fragment coupling. This synthesis protocol enables the asymmetric syntheses of four fungal meroterpenoids from commercially available materials. [ABSTRACT FROM AUTHOR]

A rhodium(II)‐catalyzed [4+2] annulation of ester‐tethered 1‐sulfonyl‐1,2,3‐triazoles and hexahydro‐1,3,5‐triazines, which features a chemoselective 1,2‐ester migration of α‐imine rhodium carbene intermediates, has been developed. Most of the valuable 1,2,3,4‐tetrahydropyrimidine derivatives were generated in good to excellent yields under mild conditions. Several important derivatization reactions have been performed. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: An efficient rhodium(II)‐catalyzed [4+3] cyclization reaction of 1‐sulfonyl‐1,2‐3‐triazoles and indoles was developed. Azepino[5,4,3‐ cd]indoles, which are widely distributed in ergot alkaloids with various biological activities, could be obtained in good to excellent yields. In addition, the total synthesis of (±)‐aurantioclavine was completed in four steps from the known compound 1a adopting this [4+3] cyclization as a key step. [ABSTRACT FROM AUTHOR]

Porphyrin‐based NiFe porous organic polymers (POPs) have been synthesized with good porosity and large BET surface areas (261 to 313 m2 g−1). These bimetallic POPs exhibit RuO2‐like OER activity, with the reaction for catalyst FeTAPP‐NiTCPP‐POP reaching a current density of 10 mA cm−2 at a low overpotential of 338 mV and with a small Tafel slope of 52 mV dec−1. FeTAPP‐NiTCPP‐POP was stable over a long period under reaction conditions. These bimetallic POPs exhibit better catalytic activity than their monometallic counterparts, due to synergetic interactions between the iron and nickel centers to facilitate the electrocatalytic process. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) have recently emerged as prospective photoactive materials coupled with Pt or Pd cocatalyst for the hydrogen evolution. Herein, we report visible‐light driven hydrogen generation catalyzed by heterogeneous systems combining CTF photosensitizers and a noble‐metal‐free cocatalyst for the first time. CTF‐HC2 was doped with two‐dimensional Ni(II) pyrimidine‐2‐thiolate ([Ni(pymt)2]n) to yield a series of x‐[Ni(pymt)2]n/CTF‐HC2 (x=3, 6, 9, 12, 15, 18 and 24 wt %) composites. Illuminated with λ>420 nm, [Ni(pymt)2]n/CTF‐HC2 materials display excellent photocatalytic performance for H2 generation from water. The highest hydrogen evolution rate is up to 3472 μmol h−1 g−1, which is 68 times of bare CTF‐HC2 (51 μmol h−1 g−1) and 1.16 times of CTF‐HC2 doped 2.0 wt % Pt (2991 μmol h−1 g−1). The efficient and recyclable heterogeneous photocatalytic H2 production from water under visible light has been established. [ABSTRACT FROM AUTHOR]

Lead zirconate titanate (PZT)‐based piezoelectric ceramics are important functional materials for various electromechanical applications, including sensors, actuators, and transducers. High piezoelectric coefficient and mechanical quality factor are essential for the resonant piezoelectric application. However, since these properties are often inversely proportional, simultaneously high performances are hard to achieve, consequently, a wide range of applications are strongly restricted. In the present study, exceptionally well‐balanced performances are achieved in PZT‐based ceramics via innovative defect engineering, which involves multi‐scale coordination among defect dipole, domain‐wall density, and grain boundary. These materials are superior to many state‐of‐the‐art commercial counterparts, which can potentially satisfy high‐end requirements for advanced electromechanical applications, such as energy harvesting, structural health monitoring, robotic sensors, and actuator. [ABSTRACT FROM AUTHOR]

A tetrabutylammonium fluoride (TBAF)‐promoted detosylation cyclization cascade was developed for the synthesis of [1,2,3]‐triazolo[5,1‐a]‐isoquinolines. Most of the products were obtained in excellent yields under mild conditions. Valuable halogen‐substituted [1,2,3]‐triazolo[5,1‐a]‐isoquinolines could also be synthesized with a slight modification of the reaction conditions. Functionalized isoquinolines were obtained smoothly by denitrogenative reactions. The control experiments showed that this transformation was facilitated by TBAF and the water contained in the commercially obtained reagent. Deuterium labeling products could also be obtained easily in high yield. [ABSTRACT FROM AUTHOR]

A divergent synthetic approach to biogenetically related diterpenoids such as ent‐kauranes, ent‐trachylobanes, ent‐beyerane, and ent‐atisane has been developed. The unified synthetic route involves the De Mayo reaction to rapidly generate the bicyclo[3.2.1]‐octane moiety of ent‐kaurane. The key reactions also include bioinspired nucleophilic cyclopropanation generating the [3.2.1.02,7]‐tricyclic core of ent‐trachylobane and regioselective cyclopropane fragmentation furnishing ent‐beyerane and ent‐atisane through the nucleophilic attack and protonation of the cyclopropane ring. This strategy enables the asymmetric total syntheses of six diterpenoids from the commercially available geraniol. [ABSTRACT FROM AUTHOR]

Annulation of benzoxy‐tethered N‐sulfonyl‐1,2,3‐triazoles and indoles has been developed in this paper, providing an efficient and convenient access to valuable cyclopenta[b]indoles in moderate to good yields. α,β‐Unsaturated imine, which generated in situ from denitrogenation and 1,2‐OBz migration of triazole, provided three carbons for the formal [3+2] cyclization reaction for the first time. [ABSTRACT FROM AUTHOR]

Readily available 1‐sulfonyl‐1,2,3‐triazole and benzoquinone‐derived alcohols were employed in a synthesis protocol for the formation of α‐(2‐hydroxyphenyl)‐α‐aminoketone. The cascade reaction includes the formation of rhodium carbene, O−H bond 1,3‐insertion, Claisen rearrangement as well as aromatization. Valuable benzoxazinone and 3‐aminobenzofuran were obtained after one‐step derivatization. Moreover, an estrone derivative was modified via the protocol with extraordinary efficiency. [ABSTRACT FROM AUTHOR]

Background: Tracheal injury could cause intratracheal scar hyperplasia which in turn causes benign tracheal stenosis (TS). With the increasing use of mechanical ventilation and ventilator, the incidence of TS is increasing. However, the molecular mechanisms of TS have not been elucidated. It is significant to further explore the molecular mechanisms of TS. Methods: The repeatability of public data was verified. Differently expressed genes (DEGs) and most significant genes were identified between TS and normal samples. Enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were analyzed. The comparative toxicogenomics database were analyzed. TS patients were recruited and RT‐qPCR were performed to verify the most significant genes. Results: There exist strong correlations among samples of TS and normal group. There was a total of 194 DEGs, including 61 downregulated DEGs and 133 upregulated DEGs. GO were significantly enriched in mitotic nuclear division, cell cycle, and cell division. Analysis of KEGG indicated that the top pathways were cell cycle, and p53 pathway. MKI67(OMIM:176741), CCNB1(OMIM:123836), and CCNB2(OMIM:602755) were identified as the most significant genes of TS, and validated by the clinical samples. Conclusion: Bioinformatics methods might be useful method to explore the mechanisms of TS. In addition, MKI67, CCNB1, and CCNB2 might be the most significant genes of TS. [ABSTRACT FROM AUTHOR]

Acyloxy‐substituted α,β‐unsaturated imines generated in situ from triazoles can act as aza‐[4 C] synthons and be trapped by indoles in a stepwise [4 + 2] cycloaddition reaction, thus providing rapid access to valuable pyrido[2,3‐b]indoles in high yields. Attractive features of this reaction system include operational simplicity, readily available substrates, construction of sterically demanding quaternary centers, and convenient derivatization using triflate. [ABSTRACT FROM AUTHOR]

Debris‐flow runout is a fascinating process to understand due to its implications for downstream alluvial fans. Based on the propagation‐deposition behaviors of the Dongyuege (DYG) debris flow, in Yunnan, the effect of biofilms on channel surfaces on debris‐flow runout is investigated in laboratory flumes with two different internal surfaces: surfaces are lined with granite slabs (Model I) and gravel (Model II), respectively. Our results show that biofilms can significantly reduce frictional resistance to flows. They increase flow velocities, slow down the deceleration of the snouts, prolong runout distances, and subsequently extend the areas covered with resulting deposits, thus greatly assisting the propagation of experimental debris flows. Slippery biofilms consisting mainly of diatoms and their extracellular mucus (ECM) reduce the contact friction between the flume‐beds and the overlying fluids, and greatly promote the propagation of tested flows. Well‐developed biofilms are found on the underwater channel surfaces of the DYG Creek. Acting as lubricating layers, they likely played a key role in the DYG debris‐flow runout. Most of the debris transported during the DYG event was deposited on overbanks, and the sediment that caused the disaster was transported to the populated fan region through the stream‐bed clad in the thick biofilms. Owing to their impacts on the development and width of the temporary debris dam breach, the stream‐bed covered with biofilms became a direct contributor to the debris‐flow hazard. Because of the ubiquitous presence of biofilms on mountain stream‐bed surfaces, the development of perennial streamflows can be viewed as an indicator of gully susceptibility to debris flows threatening creek fans. The underwater areas of pre‐event channel cross‐sections should be regarded as slip or low‐friction boundaries, and the parts above stream‐levels can be viewed as no‐slip boundaries. © 2019 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to explore whether RhoG/Rac1 was involved in migration and invasion of salivary adenoid cystic carcinoma (SACC). Materials and Methods: RhoG and Rac1 were evaluated in two SACC cell lines, namely SACC‐83 and SACC‐LM, with low and high rates of lung metastasis, respectively. Functional changes were evaluated using cell proliferation, transwell, and wound‐healing assays, and molecular events were investigated using real‐time PCR and Western blot assays. Results: RhoG and Rac1 were highly expressed and more activated in SACC‐LM cells than in SACC‐83 cells. RhoG overexpression promoted SACC‐83 cell migration and invasion through activating Rac1. The knockdown of RhoG or Rac1 partially blocked epiregulin‐induced migration and invasion in SACC‐83 cells. Epiregulin‐induced activation of RhoG/Rac1 in SACC‐83 cells was blocked by a Src inhibitor, or an AKT inhibitor or AKT siRNA, or an ERK1/2 inhibitor. Moreover, the epiregulin‐induced phosphorylation of AKT and ERK1/2 in SACC‐83 cells was blocked by a Src inhibitor, and the epiregulin‐induced phosphorylation of ERK1/2 was blocked by an AKT inhibitor or AKT siRNA. Overexpression of activated AKT induced activation of ERK1/2 and RhoG. Conclusions: RhoG/Rac1 signaling pathway was involved in SACC cell migration and invasion. RhoG/Rac1 at least partially mediated epiregulin/Src/AKT/ERK1/2 signaling to promote SACC cell migration and invasion. [ABSTRACT FROM AUTHOR]

Nowadays, developing non‐precious electrocatalysts with high performance is of primary significance in a fascinating and scalable water splitting technology for hydrogen production. A number of nickel (Ni)‐based heterogeneous catalysts have been designed and synthesized to lower the overpotentials for large current densities due to low cost and facile synthesis. Herein, recent progress on Ni‐based composites functioning on hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting is summarized. The synthesis strategies, structure design and performance analysis of Ni‐based heterostructured catalysts are thoroughly discussed, aiming to promote the development of highly efficient electrocatalysts that may ultimately replace the noble‐metal based catalysts and bring water splitting into the practical application. [ABSTRACT FROM AUTHOR]

Abstract: A chemoselective tandem reaction of 4‐acyloxymethylene‐1‐sulfonyl‐1,2,3‐triazole and vinyl ether was reported, producing polysubstituted piperidine derivatives in up to 96% yield. The key intermediate N‐sulfonyl 1‐azadiene generated by migration of the OAc group to the α‐imino rhodium carbene was isolated and a plausible mechanism was proposed. Several related ring systems were constructed from the highly functionalized products. [ABSTRACT FROM AUTHOR]

Several perfluoroalkanesulfenyl chlorides were prepared from the corresponding perfluoroalkanesulfenic acids in high yields, and their reactions with thiol, amine, arene and alkene were studied. A series of perfluoroalkyl-containing disulfides, sulfonamides, aryl sulfides and α-chlorosulfides were synthesized under mild conditions. [ABSTRACT FROM AUTHOR]

Two monocyclic members in the gracilioether family were synthesized in only three steps. The monocyclic products were further elaborated into advanced precursors to hippolachnin A and gracilioether E, respectively. Gracilioether F and the alleged structure for gracilioether I were also synthesized using a late-stage C(sp3)-H thermo-oxidation. [ABSTRACT FROM AUTHOR]

The causes for the title reaction to be limited to only the alkenes with an unsubstituted terminal alkenic carbon were explored. In some 'failed' cases the cycloaddition products actually formed but rearranged concurrently. An oxygen atom or a N-Boc (Boc= tert-butyloxycarbonyl) group at the double bond was proven essential for acquisition of intact [3+2] cycloaddition products from 1,2-disubstituted ethylenes. [ABSTRACT FROM AUTHOR]

The long-known furanoterpenes furospongin-1 and dihydrofurospongin-2 were synthesized for the first time using a chiral-pool-based route in an effort to secure the previous configurational assignments. The key C-11 stereogenic centre was taken from D-mannose, and the C-13 alkyl centre was installed exploiting the chirality of mannose. Due to deprotonation and/or enolization of the building blocks used, introduction of the furan moieties was problematic, and so some reactions had to be avoided. The trisubstituted alkene was most satisfactorily constructed using a Julia-Kocienski olefination in 1,2-dimethoxyethane, with the best ( E)/( Z) ratio achieved using a secondary sulfone. The synthetic samples not only provided the first unequivocal piece of evidence for the C-13 configuration of both natural products, but also confirmed the absolute configuration at C-11 of furospongin-1. [ABSTRACT FROM AUTHOR]

Taking advantage of the strong electron-withdrawing effect of perfluoroalkyl groups, solution-stable perfluoroalkanesulfenic acids were synthesized for the first time by Cope-type elimination of the corresponding imines; the acids were identified by 1H NMR, 19F NMR, and IR spectroscopy and mass spectrometry. Trapping reagents were utilized to capture the in situ generated sulfenic acids, which provided further experimental evidence for the formation of these fluorinated sulfenic acids. [ABSTRACT FROM AUTHOR]

A new 1,10-phenanthroline (Phen) derivative, 3,8-bis(5-methylthiophen-2-yl)-1,10-phenanthroline (PHT1), has been synthesized and fully characterized including by single-crystal X-ray structure analysis. The electron-donating effects of the two 5-methylthiophene groups lead to distinctive fluorescence emission enhancement on complexation with Zn2+ compared with non-emissive Phen. However, PHT1 shows stronger Zn2+-sensing ability than 3,8-bis(thiophen-2-yl)-1,10-phenanthroline (PHT0) or 3,8-bis(3-methylthiophen-2-yl)-1,10-phenanthroline (PHT2) and longer-wavelength fluorescence emission ( λem = 461 nm), which is vital for studies of living systems, mainly because of the lower steric hindrance and the electron-donating effects of the 5-methyl groups on the thiophene rings. More interestingly, PHT1 displays high selectivity towards Zn2+ over a broad range of pH and has an extremely low detection limit (5 ppb). An approximately 51-fold Zn2+-selective CHEF response has been attributed to the formation of a 1:2 metal-ligand complex, and the association equilibrium constant ( Kass0) of [Zn(PHT1)2](ClO4)2 was determined to be 3.4 × 1012. Anionic effects and variations in the 1H NMR spectra before and after zinc(II) ion complextion were observed. Moreover, the ability of probe PHT1 to sense Zn2+ within living HL-60, yeast, and HepG-2 cells has been explored, and the Zn2+-probing process in living cells was found to be reversible with a zinc chelator solution of N, N, N′, N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN). [ABSTRACT FROM AUTHOR]

Because of the environmental concerns of eliminating lead from piezoelectric products, bismuth‐based perovskite is becoming one of the most potential candidates. However, its relatively low thermal depolarization temperature (Td) is still an imperative obstacle hindering implementation of this material for practical application. Here, an enhanced temperature stability of 0.94(Bi0.5Na0.5)TiO3‐0.06BaTiO3 (BNTBT6) piezoceramics is reported, which can be obtained by the effective quenching process. Quenching process enhances the depolarization temperature to 136 °C, which is 40 °C higher than that of normal sintered samples. By using X‐ray photoelectron spectroscopy and electron paramagnetic resonance methods, it is revealed that oxygen vacancy may exist in the quenched samples and consequently pins the domain walls, resulting in significant enhancement of depolarization temperature. Temperature‐dependent dielectric, piezoelectric, and ferroelectric behaviors are measured as criteria to evidence the enhanced temperature stability. A quenching and annealing process is used to systematically investigate the depolarization temperature of 0.94(Bi0.5Na0.5)TiO3‐0.06BaTiO3 lead‐free piezoceramics. Oxygen vacancy, which is proved by X‐ray photoelectron spectroscopy and electron paramagnetic resonance measurements, may mainly contribute to the enhanced depolarization temperature. Structure evolution is also investigated. This work definitely sheds light on possible alternatives of increasing temperature stability of (Bi0.5Na0.5)TiO3‐based piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Aim Background Methods Results Conclusion To evaluate the mediating roles of occupational resilience and the moderationg role of perceived organizational support in the relationship between career calling and nurse burnout.Burnout is a frequent and serious problem in the field of nursing, and it poses a serious threat to both nurses’ health and patient safety. Although many studies have described the links between burnout, career calling, and occupational resilience, little is known about the actual mechanisms between career calling and nurse burnout.A cross‐sectional study of 615 nurses in China was conducted using a convenience sampling method. The data were analyzed using descriptive statistics and Pearson correlation analysis. Hypotheses were tested using structural equation models and bootstrapping methods. STROBE guidelines were followed.Career calling was found to be negatively associated with nurse burnout, and occupational resilience mediated the relationship between career calling and burnout. Additionally, perceived organizational support was found to play a moderating role in the relationship between occupational resilience and burnout.Career calling can reduce burnout by increasing nurses' levels of occupational resilience, and perceived organizational support moderates this mechanism. Hence, policies focused on encouraging and sustaining career calling should be provided by nurse managers in order to enhance stress resistance and reduce burnout. [ABSTRACT FROM AUTHOR]