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Summary: Cis‐regulatory elements (CREs) are integral to the spatiotemporal and quantitative expression dynamics of target genes, thus directly influencing phenotypic variation and evolution. However, many of these CREs become highly susceptible to transcriptional silencing when in a transgenic state, particularly when organised as tandem repeats. We investigated the mechanism of this phenomenon and found that three of the six selected flower‐specific CREs were prone to transcriptional silencing when in a transgenic context. We determined that this silencing was caused by the ectopic expression of non‐coding RNAs (ncRNAs), which were processed into 24‐nt small interfering RNAs (siRNAs) that drove RNA‐directed DNA methylation (RdDM). Detailed analyses revealed that aberrant ncRNA transcription within the AGAMOUS enhancer (AGe) in a transgenic context was significantly enhanced by an adjacent CaMV35S enhancer (35Se). This particular enhancer is known to mis‐activate the regulatory activities of various CREs, including the AGe. Furthermore, an insertion of 35Se approximately 3.5 kb upstream of the AGe in its genomic locus also resulted in the ectopic induction of ncRNA/siRNA production and de novo methylation specifically in the AGe, but not other regions, as well as the production of mutant flowers. This confirmed that interactions between the 35Se and AGe can induce RdDM activity in both genomic and transgenic states. These findings highlight a novel epigenetic role for CRE–CRE interactions in plants, shedding light on the underlying forces driving hypermethylation in transgenes, duplicate genes/enhancers, and repetitive transposons, in which interactions between CREs are inevitable. [ABSTRACT FROM AUTHOR]

The establishment of all‐carbon quaternary carbon centers represents a pivotal aspect in the synthesis of numerous natural products and pharmaceutical compounds, underscoring its paramount significance in synthetic organic chemistry. Herein, we present a novel synthetic strategy for the generation of quaternary carbon centers through the reductive coupling of tertiary halides, catalyzed by dinuclear (salen)titanium catalysts. This catalytic framework demonstrates notable reactivity towards tertiary chlorides while maintaining inertness towards secondary and primary chlorides, thereby facilitating exceptional chemoselectivity for C−C bond formation. The reaction proceeds with remarkable efficiency across a diverse range of substrates under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Background and Aims: Distinctive gut microbial profiles have been observed between patients with Wilson disease (WD) and healthy individuals. Despite this, the exact relationship and influence of gut microbiota on the advancement of WD‐related liver damage remain ambiguous. This research seeks to clarify the gut microbiota characteristics in both human patients and mouse models of WD, as well as their impact on liver injury. Methods: Gut microbial features in healthy individuals, patients with WD, healthy mice and mice with early‐ and late‐stage WD were analysed using 16S rRNA gene sequencing. Additionally, WD‐afflicted mice underwent treatment with either an antibiotic cocktail (with normal saline as a control) or healthy microbiota (using disease microbiota as a control). The study assessed gut microbiota composition, hepatic transcriptome profiles, liver copper concentrations and hepatic pathological injuries. Results: Patients with hepatic WD and mice with WD‐related liver injury displayed altered gut microbiota composition, notably with a significant reduction in Lactobacillus abundance. Additionally, the abundances of several gut genera, including Lactobacillus, Veillonella and Eubacterium coprostanoligenes, showed significant correlations with the severity of liver injury in patients with WD. In WD mice, antibiotic treatment or transplantation of healthy microbiota altered the gut microbial structure, increased Lactobacillus abundance and modified the hepatic transcriptional profile. These interventions resulted in reduced hepatic copper concentration and alleviation of WD‐related liver injury. Conclusions: Individuals and mice with pronounced WD‐related liver injury exhibited shifts in gut microbial composition. Regulating gut microbiota through healthy microbiota transplantation emerges as a promising therapeutic approach for treating WD‐related liver injury. [ABSTRACT FROM AUTHOR]

In this work, the 0.5BaCuSi4O10–0.5BaCuSi2O6‐based ceramics were synthesized using a standard solid‐phase reaction process, and the inherent relationship between crystal structure and microwave dielectric properties was thoroughly explored. The crystal structure of the 0.5BaCuSi4O10–0.5BaCuSi2O6 ceramic was determined by X‐ray diffractometer, which confirmed the existence of two phases. Microstructure observation of the ceramics was obtained by scanning electron microscope (SEM). Excellent microwave dielectric properties with a low ԑr ∼6.52, a high Q × f ∼46 010 GHz, and the temperature coefficient of resonant frequency (TCF) ∼−14 ppm°C−1 were obtained in the 0.5BaCuSi4O10–0.5BaCuSi2O6 ceramic sintered at 1060°C. By adding sintering additives LiF and Li2O–B2O3–SiO2–CaO–Al2O3 (LBSCA) glass, the sintering temperature was decreased from 1060°C to 870°C. Good microwave dielectric properties with a ԑr ∼6.59, a Q × f ∼18 820 GHz, and TCF ∼−14 ppm°C−1 were achieved in the 0.5BaCuSi4O10–0.5BaCuSi2O6 ‐2 wt.% LiF, 1 wt.% LBSCA (2F1LBSCA) ceramic sintered at 870°C. The low‐temperature firing ceramics could also be well co‐fired with Ag with good chemical compatibility. These results indicated that the 0.5BaCuSi4O10–0.5BaCuSi2O6 ceramic with 2F1LBSCA additions can be utilized in low‐temperature co‐fired ceramics technology to produce high‐frequency communication components. [ABSTRACT FROM AUTHOR]

Currently, multifunctional MXene‐integrated wearable textiles (MWTs) are particularly appealing due to their various applications such as health monitoring, smart protection, and medical treatment. However, scalable manufacture of durable, stable, and high‐performance multifunctional MWTs still face challenges due to the poor oxidation stability of MXene and low utilization of precursor titanium aluminum carbide (MAX). Herein, an improved preparation strategy for zinc ion (Zn2+) intercalation is proposed to create high antioxidative MXene (ZM) and exceptionally conductive and printable gel ink based on MXene sediments (ZMS‐ink), while multifunctional wearable textiles are fabricated using spray‐coating and screen‐printing techniques on cellulosic nonwoven textiles (CNWs), achieving the complete utilization of MXene precursor. Benefiting from the inherent disordered stacking and porous structure of CNWs, along with the highly conductive ZM and ZMS‐ink, as‐prepared smart, wearable and green‐based pressure sensor offered proper breathability, high sensitivity (2602.26 kPa−1), wide sensing range (0–141 kPa), and excellent cycling stability (>5000 cycles). Additionally, the sensor exhibited efficient photothermal/photodynamic therapy antibacterial activity and exceptional electromagnetic interference shielding performance (57.5 dB). Therefore, this work paves the way for the future development of integrated and scalable multifunctional wearable devices building on the environmental‐friendly CNWs incorporated with fully utilized MAX, offering a green and cost‐effective approach. [ABSTRACT FROM AUTHOR]

The hot deformation behavior of 22Cr‐25Ni austenitic heat‐resistant steel at the temperatures of 950–1150 °C and strain rates of 0.01–10 s−1 is studied by isothermal compression test. It is found that the dynamic recrystallization (DRX) degree of the steel increases with the increase of temperature. The DRX degree decreases with the increase of the strain rate from 0.01 to 1 s−1, whereas the DRX degree increases with the increase of the strain rate from 1 to 10 s−1. The hot deformation activation energy is as high as 624.25 kJ mol−1 due to the addition of a large number of alloying elements. The typical strain compensation Arrhenius constitutive model established can be used to roughly predict the hot flow behavior of the steel. Furthermore, a modified model considering the influence of strain rate and deformation heat on the deformation process is proposed and showed higher accuracy (statistical parameters r = 0.994 and average absolute relative error = 4.59%). The DRX zone of the steel is determined to be 1080–1150 °C/0.01–0.1 s−1 through processing map analysis, representing the appropriate hot working zone. The microstructure corresponding to the instability zone in the processing map exhibits deformation concentration bands or necklace structures. [ABSTRACT FROM AUTHOR]

Melatonin (MT) has been implicated in the plant response to phosphorus (P) stress; however, the precise molecular mechanisms involved remain unclear. This study investigated whether MT controls internal P distribution and root cell wall P remobilization in rice. Rice was treated with varying MT and P levels and analyzed using biochemical and molecular techniques to study phosphorus utilization. The results demonstrated that low P levels lead to a rapid increase in endogenous MT levels in rice roots. Furthermore, the exogenous application of MT significantly improved rice tolerance to P deficiency, as evidenced by the increased biomass and reduced proportion of roots to shoots under P‐deficient conditions. MT application also mitigated the decrease in P content regardless in both the roots and shoots. Mechanistically, MT accelerated the reutilization of P, particularly in the root pectin fraction, leading to increased soluble P liberation. In addition, MT enhanced the expression of OsPT8, a gene involved in root‐to‐shoot P translocation. Furthermore, we observed that MT induced the production of nitric oxide (NO) in P‐deficient rice roots and that the mitigating effect of MT on P deficiency was compromised in the presence of the NO inhibitor, c‐PTIO, implying that NO is involved in the MT‐facilitated mitigation of P deficiency in rice. Overall, our findings highlight the potential of MT as a promising strategy for enhancing rice tolerance to P deficiency and improving P use efficiency in agricultural practices. [ABSTRACT FROM AUTHOR]

Proteolysis targeting chimeras (PROTACs) have emerged as a promising strategy for drug discovery and exploring protein functions, offering a revolutionary therapeutic modality. Currently, the predominant approach to PROTACs discovery mainly relies on an empirical design–synthesis–evaluation process involving numerous cycles of labor‐intensive synthesis‐purification and bioassay data collection. Therefore, the development of innovative methods to expedite PROTAC synthesis and exploration of chemical space remains highly desired. Here, a direct‐to‐biology strategy is reported to streamline the synthesis of PROTAC libraries on plates, enabling the seamless transfer of reaction products to cell‐based bioassays without the need for additional purification. By integrating amide coupling and light‐induced primary amines and o‐nitrobenzyl alcohols cyclization (PANAC) photoclick chemistry into a plate‐based synthetic process, this strategy produces PROTAC libraries with high efficiency and structural diversity. Moreover, by employing this platform for PROTACs screening, we smoothly found potent PROTACs effectively inhibit triple‐negative breast cancer (TNBC) cell growth and induce rapid, selective targeted degradation of cyclin‐dependent kinase 9 (CDK9). The study introduces a versatile platform for assembling PROTACs on plates, followed by direct biological evaluation. This approach provides a promising opportunity for high‐throughput synthesis of PROTAC libraries, thereby enhancing the efficiency of exploring chemical space and accelerating the discovery of PROTACs. [ABSTRACT FROM AUTHOR]

The introduction of nitrogen‐containing functional groups to chiral polymer backbones enables the tailoring of physical properties and offers opportunities for further post‐polymerization modification. However, the substrate scope of such polymers is extremely limited because monomers having nitrogen‐containing groups can change coordination state with respect to the metal centers, thus decreasing the activity and enantioselectivity and even poisoning the catalyst completely. In this paper, we report our attempts to carry out the asymmetric copolymerization of meso‐epoxide with highly reactive isocyanates. In particular, we found that biphenol‐linked bimetallic Co(III) complexes with multiple chiral centers are very efficient in catalyzing this asymmetric copolymerization reaction, affording optically active polyurethanes with a completely alternating nature and a high enantioselectivity of up to 94 % ee. Crucially, we identified that the steric hindrance at the phenolate ortho position of the ligand strongly influences the catalytic activity and product enantioselectivity. In addition, density functional theory calculations revealed that the highly sterically bulky substituents change the mechanism from bimetallic to monometallic, and result in the unexpected inversion of the chiral induction direction. Moreover, the high stereoregularity of the produced polyurethanes enhances their thermal stability, and they can be selectively decomposed into oxazolidinones. This study offers a versatile methodology for the synthesis of chiral polymers containing nitrogen functionalities. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the role of forkhead box O1 (FoxO1) inhibitor AS1842856 (AS) in nonalcoholic steatohepatitis (NASH) mice and the potential mechanisms. Methods: Mice were given methionine‐choline‐sufficient (MCS), or methionine‐ and choline‐deficient (MCD) diet for 5 weeks, along with AS (60 mg/kg) or vehicle gavage treatment (0.2 mL/day). Body and liver weight, serum triglyceride (TG), low‐density lipoprotein‐cholesterol (LDL‐C), high‐density lipoprotein‐cholesterol (HDL‐C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), fasting glucose and insulin levels were measured. Liver macrophage infiltration and ileal ZO‐1 protein expression were also detected. Interleukin (IL)‐6, IL‐1β, and tumor necrosis factor (TNF)‐α, sterol regulatory element binding protein (SREBP)‐1c, phosphoenolpyruvate carboxykinase (PEPCK), and glucose‐6‐phosphatase (G6Pase), α‐smooth muscle actin (SMA), recombinant collagen type III α1 (Col3a1), and connective tissue growth factor (Ctgf) expressions were measured. Stool samples were collected for 16S rDNA sequencing. Results: Compared to the MCD group, AS attenuated liver weight, reduced serum TG, ALT, and AST levels, increased HDL‐C levels, mitigated hepatic steatosis, decreased macrophage infiltration, and augmented ileal ZO‐1 proteins in NASH mice. It also reduced the levels of IL‐6, IL‐1β, and TNF‐α, alongside with the Srebp‐1c mRNA expression. However, no significant effects on Pepck, G6Pase, α‐SMA, Col3a1, or Ctgf were observed. Furthermore, AS promoted diversity and altered gut microbiota composition in NASH mice, causing increased beneficial bacteria like Akkermansia muciniphila, Parabacteroides distasonis, and Prevotellamassilia, which were associated with metabolic functions. Conclusion: FoxO1 inhibitor AS ameliorated hepatic steatosis, inflammation, and intestinal dysbiosis in NASH mice, making it a potentially promising treatment for NASH. [ABSTRACT FROM AUTHOR]

Copper with equiaxed grains (EG Cu), copper with columnar nanotwinned grains (C‐NT Cu), and copper with mixed equiaxed and columnar grains (MG Cu) are electroplated on pads and redistributed layers (RDLs) with different dimensions. When the diameters of pads increase from 40 to 105 μm, the flatness of pads decreases from 34.5% to 24.0%. The flatness gradually deteriorates from 16.5% to 34.4% with the increase of RDL width from 8 to 20 μm. In contrast, the flatness of C‐NT Cu and MG Cu fluctuates between 1% and 5%, showing a weak correlation on the dimension. In terms of microstructure, the EG Cu and MG Cu has a weak correlation with size change, and the grain orientation shows a randomness. However, the (111) texture component of C‐NT Cu differs greatly with different dimensions, especially in transition layer. The (111) texture component changes from 9.6% to 38.1% for ϕ 40–105 μm pad and from 14.3% to 18.9% for 8–20 μm‐wide RDL. The study reveals the significant size effect on the deposited profile and microstructure of electrodeposited copper materials, which should give insights of the materials design in advanced packaging technology. [ABSTRACT FROM AUTHOR]

Pressure‐induced emission enhancement (PIEE) is a novel phenomenon in contrast to conventional pressure‐induced emission quenching, and has attracted considerable attention owing to the potential application of materials with this effect as optical pressure‐sensing devices. The urgent need and significant significance lie in the design and exploration of systems that possess high‐efficiency PIEE. Here, a large PIEE in a novel zero‐dimensional (0D) hybrid manganese bromide is realized, (BPPH)2MnBr4·1.5CH3CN [BPPH+ = bis(triphenylphosphine)iminium]. The experimental and theoretical results demonstrate that such emission enhancement is primarily attributed to the pressure‐induced reconfiguration of electronic band alignment and resultant redistribution of band‐edge excitons. Under compression, the electronic bandgap of (MnBr4)2− experiences a more rapid reduction compared to that of the organic cations. Consequently, this leads to the gradual closure of the charge transfer pathway from (MnBr4)2− to BPPH+. This progression results in a higher retention of excitons on (MnBr4)2−, amplifying the efficiency of Mn2+d–d transitions, and leading to a substantial enhancement in emission. This study not only offers fresh insights into the behavior of carrier dynamics induced by pressure in hybrid manganese halides but also presents a promising avenue for the advancement of PIEE systems. [ABSTRACT FROM AUTHOR]

Background and Purpose: The mammalian target of rapamycin (mTOR) pathway plays critical roles in intrinsic chemoresistance by regulating Fanconi anaemia complementation group D2 (FANCD2) expression. However, the mechanisms by which mTOR regulates FANCD2 expression and related inhibitors are not clearly elucidated. Extracts of Centipeda minima (C. minima) showed promising chemosensitizing effects by inhibiting FANCD2 activity. Here, we have aimed to identify the bioactive chemosensitizer in C. minima extracts and elucidate its underlying mechanism. Experimental Approach: The chemosensitizing effects of arnicolide C (ArC), a bioactive compound in C. minima, on non‐small cell lung cancer (NSCLC) were investigated using immunoblotting, immunofluorescence, flow cytometry, the comet assay, small interfering RNA (siRNA) transfection and animal models. The online SynergyFinder software was used to determine the synergistic effects of ArC and chemotherapeutic drugs on NSCLC cells. Key Results: ArC had synergistic cytotoxic effects with DNA cross‐linking drugs such as cisplatin and mitomycin C in NSCLC cells. ArC treatment markedly decreased FANCD2 expression in NSCLC cells, thus attenuating cisplatin‐induced FANCD2 nuclear foci formation, leading to DNA damage and apoptosis. ArC inhibited the mTOR pathway and attenuated mTOR‐mediated expression of E2F1, a critical transcription factor of FANCD2. Co‐administration of ArC and cisplatin exerted synergistic anticancer effects in the A549 xenograft mouse model by suppressing mTOR/FANCD2 signalling in tumour tissues. Conclusion and Implications: ArC suppressed DNA cross‐linking drug‐induced DNA damage response by inhibiting the mTOR/E2F1/FANCD2 signalling axis, serving as a chemosensitizing agent. This provides insight into the anticancer mechanisms of ArC and offers a potential combinatorial anticancer therapeutic strategy. [ABSTRACT FROM AUTHOR]

Background: The surgical Apgar score (SAS) quantifying three intraoperative indexes has been confirmed to be significantly associated with postoperative morbidity and prognosis in many surgical specialties. However, there are great limitations in its application for esophageal cancer (EC). This study aimed to assess the predictive capability of esophagectomy SAS (eSAS) in determining postoperative morbidity and overall survival (OS) in EC patients who had undergone neoadjuvant therapy. Methods: A retrospective evaluation was conducted on a cohort of 221 patients in which surgery- and tumor-related data were extracted and analyzed. Major morbidity was defined as complications meeting the criteria of Clavien-Dindo classification III or higher during hospitalization. Univariate and multivariate analyses were performed to identify potential risk factors for major morbidity. Kaplan-Meier analysis was utilized to calculate the OS and relapse-free survival (RFS). Results: The results exhibited that eSAS demonstrated potential predictive value for postoperative morbidity with an optimal cutoff value of 6. The eSAS and diabetes mellitus were two independent risk factors for the major morbidity; however, no correlation between the eSAS and the OS or RFS was detected. Conclusion: The eSAS could be used as a predictor of major morbidity, while it was not correlated with OS and RFS. [ABSTRACT FROM AUTHOR]

Artificial electronic skin (E‐skin), a class of promising materials mimicking the physical‐chemical and sensory performance of the human skin, has gained extensive interest in the field of human health‐monitoring and robotic skins. However, developing E‐skin simultaneously achieving high resilience, hysteresis‐free, and absent external power is always a formidable challenge. Herein, a liquid‐free eutectic gel‐based self‐powered E‐skin with high resilience, fatigue resistance, and conductivity is prepared by introducing hydroxypropyl cellulose (HPC) into metal salt‐based deep eutectic solvents (MDES). The unique structural design of cellulose‐anchored permanent entangled poly(acrylic acid) (PAA) chain, in combination with rapid broken/reconstruction of the dense dynamic sacrificial bonds, realizes the fabrication of high‐elastic E‐skin with negligible hysteresis. This further demonstrates the promising practical application of the cellulose‐based eutectogel with high transmittance (92%), high conductivity (36.6 mS m−1), and high resilience (98.1%), and excellent environment stability in robust triboelectric nanogenerator for energy harvesting and high resilience, self‐powered E‐skin for human health‐caring and human‐machine interaction. [ABSTRACT FROM AUTHOR]

Malleable thermosets as dynamic covalent cross‐linked polymers, simultaneously possessing the advantages of thermosets and thermoplastics, have attracted considerable attention. Although several reprocessing concepts have been demonstrated, the fabrication of fast‐curing bio‐based strong and tough malleable thermosets for advanced applications in electronics remains a great challenge. Herein, a novel construction strategy of combining hindered urea bonds (HUB) and radical polymerization is developed to prepare fast‐photocurable and mechanically robust cellulose‐based malleable bio‐thermosets (CMTs). In this strategy, the functional cellulose macromonomer simultaneously has acrylate groups and HUB is first synthesized and employed as a macro‐crosslinker to react with plant oil‐based monomer to construct the malleable bio‐thermosets with "soft (plant oil‐based polymer)" and "hard (rigid cellulose)" phase architecture through the fast photocuring. The CMTs exhibit excellent flexibility and high toughness (2.89 MJ m−3), and the introduction of dynamic HUB endows the CMTs with excellent malleability and reprocessability by heating compression molding or solvent regeneration, the recovery efficiency reached 94.7%. More impressively, the CMTs can be used as substrates to fabricate CMTs/silver composite for anti‐icing or de‐icing devices, and CMTs‐based capacitive sensors for monitoring environmental humidity or human health. This work paves a new strategy to develop new‐generation fast‐photocurable mechanically robust, malleable bio‐thermosets for multifunctional electronic devices. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) variants continue to emerge and cocirculate in humans and wild animals. The factors driving the emergence and replacement of novel variants and recombinants remain incompletely understood. Herein, we comprehensively characterized the competitive fitness of SARS‐CoV‐2 wild type (WT) and three variants of concern (VOCs), Alpha, Beta and Delta, by coinfection and serial passaging assays in different susceptible cells. Deep sequencing analyses revealed cell‐specific competitive fitness: the Beta variant showed enhanced replication fitness during serial passage in Caco‐2 cells, whereas the WT and Alpha variant showed elevated fitness in Vero E6 cells. Interestingly, a high level of neutralizing antibody sped up competition and completely reshaped the fitness advantages of different variants. More importantly, single clone purification identified a significant proportion of homologous recombinants that emerged during the passage history, and immune pressure reduced the frequency of recombination. Interestingly, a recombination hot region located between nucleotide sites 22,995 and 28,866 of the viral genomes could be identified in most of the detected recombinants. Our study not only profiled the variable competitive fitness of SARS‐CoV‐2 under different conditions, but also provided direct experimental evidence of homologous recombination between SARS‐CoV‐2 viruses, as well as a model for investigating SARS‐CoV‐2 recombination. [ABSTRACT FROM AUTHOR]

To reveal the failure mechanism of fractured sandstone under the influence of the infilling material strength, uniaxial compression tests, and PFC3D numerical simulation analyses were conducted on fractured sandstone with different infilling material strengths, and the influence of the infilling material strength on the basic mechanical properties of the fracture‐filled sandstone was studied. The results showed that, with increasing infilling material strength, the peak strength and elastic modulus of the specimens increased nonlinearly and eventually stabilized. The failure pattern of the specimens changed from shear to tensile. When the infilling material strength was low, a wing crack or anti‐wing crack was generated; however, when the infilling material strength was high, a vertical tensile crack was generated. From the perspective of fracture mechanics, the filling of sandstone cracks can reduce or even suppress the stress concentration effect at the prefabricated crack tip and improve the bearing capacity of the fractured sandstone. Highlights: The basic mechanical properties of the fracture‐filled sandstone specimens were obtained.PFC3D numerical simulation analyses were conducted on fractured sandstone.The influence mechanism of filling materials on the fractured rock was revealed. [ABSTRACT FROM AUTHOR]

An asymmetric intramolecular hydroalkylation of unactivated internal olefins with tethered cyclic ketones was realized by the cooperative catalysis of a newly designed chiral amine (SPD‐NH2) and PdII complex, providing straightforward access to either bridged or fused bicyclic systems containing three stereogenic centers with excellent enantioselectivity (up to 99 % ee) and diastereoselectivity (up to >20 : 1 dr). Notably, the bicyclic products could be conveniently transformed into a diverse range of key structures frequently found in bioactive terpenes, such as Δ6‐protoilludene, cracroson D, and vulgarisins. The steric hindrance between the Ar group of the SPD‐NH2 catalyst and the branched chain of the substrate, hydrogen‐bonding interactions between the N−H of the enamine motif and the C=O of the directing group MQ, and the counterion of the PdII complex were identified as key factors for excellent stereoinduction in this dual catalytic process by density functional theory calculations. [ABSTRACT FROM AUTHOR]

A nuclearity‐dependent enantiodivergent epoxide opening reaction has been developed, in which both antipodes of chiral alcohol products are selectively accessed by mononuclear (salen)TiIII complex and its self‐assembled oxygen‐bridged dinuclear counterparts within the same stereogenic ligand scaffold. Kinetic studies based on the Eyring equation revealed an enthalpy‐controlled enantio‐differentiation mode in mononuclear catalysis, whereas an entropy‐controlled one in dinuclear catalysis. DFT calculations outline the origin of the enantiocontrol of the mononuclear catalysis and indicate the actual catalyst species in the dinuclear catalytic system. The mechanistic insights may shed a light on a strategy for stereoswichable asymmetric catalysis utilizing nuclearity‐distinct transition‐metal complexes. [ABSTRACT FROM AUTHOR]

Background: We aimed to explore the prognostic differences among T1‐4N0‐2M0 non‐small cell lung cancer (NSCLC) patients with bronchus involvements and to validate the T category of these patients in an external cohort. Methods: Univariable and multivariable Cox analysis was performed to determine the prognostic factors. Kaplan–Meier method with a log‐rank test was used to compare overall survival differences between groups. Propensity score matching method was used to minimize the bias caused by the imbalanced covariates between groups. Results: A total of 169 390 eligible T1‐4N0‐2M0 NSCLC cases were included. There were 2354, 3367, 1638, 75, 87 585, 42 056, 19 246, and 13 069 cases in the group of superficial tumors of any size with invasive component limited to bronchial wall (T1‐bronchus), tumors involving main stem bronchus ≥2 cm from carina (T2‐main bronchus [≥2 cm]), tumors involving main stem bronchus <2 cm from carina (T2‐main bronchus [<2 cm]), tumors with carina invasion (T4‐carina), T1, T2, T3, and T4, respectively. Multivariable Cox analysis indicated that T1‐bronchus patients had the best prognosis; T2‐main bronchus (≥2 cm) and T2‐main bronchus (<2 cm) patients had similar prognosis both in the entire cohort and in several subgroups. Survival curves showed that T1‐bronchus and T1 patients had similar survival rates; the survivals of T2‐main bronchus patients regardless of the distance from carina were comparable to those of T2 patients, and the survivals of T4‐carina patients were also similar to those of T4 patients. Conclusions: Our results validated and supported the current T category for the patients with bronchus involvements, which might provide certain reference value for the revisions of T category in the next version of the tumor‐node‐metastasis stage classification. [ABSTRACT FROM AUTHOR]

Bulk chemical 2‐methyl‐2‐butene, one of the main C5 distillates of the petrochemical industry, has scarcely been utilized directly in synthesizing high‐value‐added fine chemicals. Herein, we use 2‐methyl‐2‐butene as the starting material to develop a palladium‐catalyzed highly site‐ and regio‐selective C‐3 dehydrogenation reverse prenylation of indoles. This synthetic method features mild reaction conditions, a broad substrate scope, atom‐ and step‐economies. [ABSTRACT FROM AUTHOR]

Background and Purpose: The detection and characterization of functional activities in the gray matter of schizophrenia (SZ) have been widely explored. However, the relationship between resting‐state functional signals in the white matter of first‐episode SZ and short‐term treatment response remains unclear. Methods: Thirty‐six patients with first‐episode SZ and 44 matched healthy controls were recruited in this study. Patients were classified as nonresponders and responders based on response to antipsychotic medication during a single hospitalization. The fractional amplitude of low‐frequency fluctuation (fALFF), regional homogeneity (ReHo), and functional connectivity (FC) of white matter were calculated. The relationships between functional changes and clinical features were analyzed. In addition, voxel‐based morphometry was performed to analyze the white matter volume. Results: One‐way analysis of variance showed significant differences of fALFF and ReHo in the left posterior thalamic radiation and left cingulum (hippocampus) in the patient group, and the areas were regarded as seeds. The FC was calculated between seeds and other white matter networks. Compared with responders, nonresponders showed significantly increased FC between the left cingulum (hippocampus) and left posterior thalamic radiation, splenium of corpus callosum, and left tapetum, and were associated with the changes of clinical assessment. However, there was no difference in white matter volume between groups. Conclusion: Our work provides a novel insight that psycho‐neuroimaging‐based white matter function holds promise for influencing the clinical diagnosis and treatment of SZ. [ABSTRACT FROM AUTHOR]

Summary: This study proposes a feature fusion one‐dimensional convolutional neural network algorithm model with a portable non‐dimensionality reduction attention mechanism to resolve the limitations pertaining to the small training sample capacity of conventional deep learning models, single feature‐extractor size, insufficient feature extraction of the bearing faults, and low recognition rate of the bearing health status under variable loads and strong noise. This model regarded raw vibration signal as input, used the feature fusion module to extract multiscale time information, and the convolution‐pooling alternating layer adaptively overcome the time‐dependent limitations. An adaptive batch normalization was introduced to reduce the divergence in sample distribution between the source and target domains and enhance the model generalization capabilities. Moreover, the non‐dimensionality reduction attention mechanism is a more efficient channel weight distribution algorithm that can enhance the anti‐noise performance of the model. After embedding the non‐dimensionality reduction attention mechanism, the proposed network could enhance the anti‐noise performance of the model through a special channel‐weight learning method. It combined the Softmax classification layer to construct a feature extraction feature classification dual intelligent fault diagnosis algorithm. The experiments were performed on the rolling bearing fault dataset. The results revealed that the method provided a rather high generalization ability and stable anti‐noise ability. Simultaneously, the introduction of t‐SNE dimensionality reduction visualization revealed the strong feature‐extraction ability of the deep network model for large‐volume samples. [ABSTRACT FROM AUTHOR]

This mini‐review summarizes catalytic asymmetric synthetic methodologies for preparing 2,5‐diketopiperazine (DKP) frameworks since 1990, with two types of synthetic precursor, namely linear materials and cyclic pre‐chiral substrates, discussed. This review provides guidance for the further design and development of novel catalytic asymmetric methods for preparing functionalized DKP‐containing molecules. [ABSTRACT FROM AUTHOR]

The fatigue life prediction of the bearings is a crucial and challenging issue, especially under random cyclic loadings. Although numerous methods have been proposed, the remaining useful life of bearings is still unclear. In this study, the tensile and fatigue properties of high‐speed train bearings after various operating mileages were investigated. The experimental results reveal that the microhardness, tensile strength, elongation, and fatigue strength of the bearing steel present a downward trend with increasing the operating mileage. Based on Miner's law, we proposed the generalized linear cumulative damage theory, which illustrates that fatigue damage of components per unit mileage can be linearly superimposed. Accordingly, the residual strength model was established to evaluate the fatigue life of high‐speed train bearings. It would provide a new insight for the fatigue life prediction of bearings under random loadings. Highlights: The fatigue damage behavior of high‐speed train bearings was systematically explored.The tensile and fatigue strength show a downward trend with the operating mileage.The fatigue life calculated by residual static/fatigue strength is 10–27 and 6 million km.It provides a new insight into the fatigue life prediction of engineering components. [ABSTRACT FROM AUTHOR]

Flexible epoxy thermosets have promising applications in modern industry. However, the development of next‐generation flexible epoxy thermosets with high biomass content and multi‐functions remains challenging. In this work, a sustainable cellulose/plant oil based flexible epoxy thermoset with excellent mechanical property, reprocessing performance, and UV absorption property was prepared. First, the amino cellulose is synthesized and used as a reinforcement and curing agent, and then the flexible epoxy thermoset is prepared by curing reaction of amino cellulose, citric acid, and flexible epoxy resin using zinc acetylacetonate as the transesterification catalyst. The epoxy thermosets show excellent thermal stability, the temperature at maximum weight loss reached 425°C. Mechanical property tests indicate that these thermosets have high mechanical strength (19.6 MPa) and satisfactory stretchability (36.1%–118%). The dynamic transesterification ester groups endow the epoxy thermoset with reprocessing ability. In addition, these epoxy thermosets show outstanding and stable UV absorption properties even after long‐time UV‐light irradiation or heating treatment, which makes these flexible epoxy thermosets have promising applications in UV‐blocking coating. [ABSTRACT FROM AUTHOR]

Midnight and post‐midnight ionospheric irregularities are observed over Brazil sector during the June solstice of solar inactive years. The prevailing nighttime winds in the magnetic meridional plane (magnetic meridional winds) are experimentally described as a trans‐equatorial wind, and superposed a convergent/equatorward component that emerges after 03 LT. Further computation of the growth rate of the generalized Rayleigh‐Taylor (GRT) instability well explains the local time dependent irregularities observed. Our analysis indicates that the trans‐equatorial wind before midnight uplifts the ionosphere in the upwind (northern) hemisphere, whereas the expected downwelling in the conjugate hemisphere is almost unseen. The wind hence decreases the field‐line integrated Pedersen conductivity and promotes the midnight instability, instead of suppressing it as conventionally known. After 03 LT, the convergent/equatorward component also provides an unstable condition, consistent with the theory that a meridional wind profile with a negative latitudinal gradient will destabilize the ionosphere. The growth rate gets lower as the neutral winds weakened with increasing solar activity, but seemingly insufficient to explain the much fewer instabilities observed in 2012 than in 2009. Other solar activity dependent factors need to be taken into account in addition to the growing process of the GRT instability in the F region. Key Points: Local time variations of the neutral winds in Brazil sector are reconstructed by combining the SAMI2 model and ionospheric hmF2 dataEquatorward winds superposed on a trans‐equatorial wind well explain the occurrence of copious midnight/post‐midnight irregularitiesEither of the two components effectively uplifts the ionosphere and contributes to the growth rate of the generalized Rayleigh‐Taylor instability [ABSTRACT FROM AUTHOR]

The characteristics of winter nighttime enhancement (WNE) of the midlatitude ionosphere at 300, 550, and 750 km altitude are presented, based on the radio occultation data from the Constellation Observing System for Meteorology, Ionosphere, and Climate. WNE at 750 km altitude has earlier start time and larger increasing rate than that at 550 km, possibly due to the downward plasma diffusion from above that dominates the most upper part of the ionosphere. Theoretical calculation of the plasma transport at 300 km altitude reveals the largest effect of downward diffusion at 45° geomagnetic latitude, consistent with the latitudinal distribution of WNE. Meanwhile, the wind‐driven plasma transport also contributes to WNE, at 30°W–180°W geographic longitude in the Southern Hemisphere. The strength and end time of WNE vary with longitude, and are correlated with the longitudinal variations of the enhancement in the conjugate (summer) hemisphere. This may be attributed to the transport processes in the interhemispheric geomagnetic flux tubes, which redistribute and balance the plasma between the conjugate hemispheres at night. The plasma flux from above is hence an important plasma source for further understanding of both the winter and summer nighttime enhancements. Key Points: Stronger winter nighttime enhancement with earlier start time is observed at 750 km than at 550 km altitudeThe downward diffusive flux dominates the formation of the enhancement, while the neutral wind also contributes at certain longitudesThe plasma flux from above could be an important plasma source for both the winter and summer nighttime enhancements [ABSTRACT FROM AUTHOR]

Summary: To make high‐value utilisation of citrus peel waste, three simple extraction techniques (acidic, alkaline and hydrothermal methods) were used to prepare pectins from navel orange peel. The influence of different methods on the structure and antioxidant capacities of all pectin preparations was investigated and compared. All findings revealed that the yield, degree of esterification, molecular weight, monosaccharide composition and antioxidant activities of all samples were significantly different. Alkali‐extracted pectin exhibited highest yield (22.6%), acid‐extracted pectin belonged to high‐ester pectin and hydrothermal‐extracted pectin had lowest molecular weight (109.2 kDa). Interestingly, due to the superior proportion of side‐chain structure, alkali‐extracted pectin possessed a better ability to scavenge free radicals than other samples. More importantly, alkali‐extracted pectin could protect macrophages from H2O2‐induced oxidative damage by enhancing SOD activity and reducing MDA levels. All results contributed to our knowledge of the association among extraction techniques, structural characteristics and resultant bioactivities for pectic polysaccharides. [ABSTRACT FROM AUTHOR]

We describe an efficient method for α‐functionalization of N‐aryl‐tetrahydroisoquinolines under visible‐light‐irradiation catalyzed by organic photocatalyst. This protocol provides a concise and environmental approach for the rapid allylation and benzylation of N‐aryl‐tetrahydroisoquinolines, and shows broad substrate scope. Stable organoboron reagents have shown their ability in the construction of challenging Csp3−Csp3 bond. The load of the photocatalyst is low and the oxidant is inexpensive and less toxic. [ABSTRACT FROM AUTHOR]

Photocatalytic carbon dioxide (CO2) reduction technology is considered a promising approach to alleviate greenhouse gas emissions in the earth's atmosphere. Carbon dots (CDs), which possess good optical properties, are of keen interest in the field of photocatalysis. Iron (Fe), a transition metal element with vacant 3d orbital that contributes to the electron‐transfer process, is a promising metal dopant for CDs that allows for the preparation of multifunctional CDs. Fe‐doped carbon dots (Fe−CDs) were synthesized using ethylenediamine tetraacetic acid disodium (EDTA‐2Na) and ferric chloride (FeCl3 ⋅ 6H2O) through a simple one‐step hydrothermal method. The chemical structure of the obtained Fe−CDs was studied, and their activity for the photocatalytic reduction of CO2 was tested. The results show that Fe doping amount of 13.0 wt.% is the most favorable for the photocatalytic reaction. The maximum photocatalytic reduction of CO2 to methanol reaches 654.28 μmol ⋅ g−1 ⋅ h−1 within 6 h, which is about 2.6 times of the methanol yield of CDs, which is attributed to high electron transfer rate of Fe dopant. [ABSTRACT FROM AUTHOR]

The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74‐fold reduction in the 50% lethal dose (LD50). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI‐BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogen atom transfer (HAT) represents arguably one of the most straightforward access to the significant chiral tertiary carbon centers, however, remains a long‐standing challenge. Herein, the first example of catalytic coordination‐induced asymmetric HAT reaction has been developed relying on a sequential (salen)TiIII‐initiated radical generation and (salen)TiIV‐controlled enantioselective HAT process. The reaction transforms easily accessible glycidic esters, thioesters and amides to synthetically valuable formal formaldehyde aldol adducts in an enantioconvergent manner, along with broad scope and highly regio‐ and enantioselectivities. [ABSTRACT FROM AUTHOR]

The development of flexible conductive elastomers integrating renewable feedstock, splendid mechanical property, and excellent weather resistance is of major interest and challenge. Here, a novel strategy is reported to construct the liquid‐free cellulose‐derived ionic conductive elastomer that is successfully applied in the wearable sensor and triboelectric nanogenerators (TENG). In this strategy, the ionic conductive elastomer with physical and chemical dual‐crosslinking network is prepared via in situ polymerization of the polymerizable deep eutectic solvent. The construction of dual‐crosslinking network improves the mechanical strength and toughness more than 2 times, and the cellulose contributes to forming the dense hydrogen bond crosslinking network that can improve the recyclability, anti‐freezing, and solvent‐resistance performance. Benefiting from these features, the ionic conductive elastomer is successfully applied in the wearable sensors and TENG for monitoring human motion, and in harvesting mechanical energy to convert into stable electrical outputs to light the LEDs, charge the capacitor, and power the electronic watch. The ionic conductive elastomer maintains reliable sensing and energy harvesting performance even after recycling, soaking in organic solvent, or at low/high temperature. This study paves a promising strategy for fabricating sustainable and multifunction flexible electronics that are suitable for harsh environments. [ABSTRACT FROM AUTHOR]

Shape memory epoxy thermosets (SMETs) have attracted more and more attention in artificial intelligence applications. However, the fabrication of lightweight and high‐strength bio‐based SMET with multiple‐response shape memory properties remains a challenge. Herein, a thermal and light‐triggered bio‐based SMET with excellent mechanical property and toughness is prepared. To fabricate the SMET, a bio‐based curing agent (CFMA) derived from cardanol, menthane diamine and furfural is utilized to react with epoxy resin E51 to prepare the SMET. The curing kinetics of SMET is measured by non‐isothermal DSC, and the reaction order is 0.784. The SMETs have excellent thermal stability and mechanical strength. Based on the toughening effect of the bio‐based curing agent, the SMETs exhibit excellent stretchability, and the toughness of the SMETs improves gradually with the increase in curing agent content. Furthermore, the SMET exhibits excellent thermal and light‐triggered shape memory properties, and the SMET with broad glass transition shows triple‐shape memory property. These multiple stimulus–response bio‐based SMETs with lightweight and high strength have potential applications in the field of actuators and intelligent electronic devices. [ABSTRACT FROM AUTHOR]

It is generally recognized that the fatigue failure of the cracked engineering components is a crucial issue, especially considering the sample thickness effect. Although numerous methods have been proposed, it is still unclear about the sample thickness effect on the fatigue crack growth (FCG) rate of metallic materials. Based on the plasticity‐induce crack closure and crack tunneling effect, we established an improved FCG model with a thickness factor T by the load analysis near the crack tip. The thickness factor could clarify the sample thickness effect on the FCG rate of high‐strength steels. Numerous fatigue data demonstrates that the improved model displays a fairly good relationship between the sample thickness and FCG rate. It would provide a new strategy to the FCG rate prediction of cracked structures through small size specimen. Highlights: We propose an improved model to illustrate the effect of specimen thickness on the FCG behavior.The thickness factor T provides a fairly accurate relation between the specimen thickness and FCG rate.The model would be an effective strategy to the fatigue life prediction of cracked components. [ABSTRACT FROM AUTHOR]

BACKGROUND: Agrotis ipsilon and A. segetum are major migratory pests of many crops in China, and frequent regional outbreaks cause severe yield losses. Use of food attractants is one of the most promising control methods against adult lepidoptera, notably through the attract‐and‐kill strategy. Chlorantraniliprole's acute toxicity and sublethal effects on both moths were evaluated. RESULTS: Chlorantraniliprole showed high activity against both adults of both species, with LC20 and LC50 values of 0.08 and 0.21 mg L−1 (A. ipsilon), and 0.14 and 0.51 mg L−1 (A. segetum). The fecundity, effective oviposition rate, and egg hatching rate of both species in dual‐sex exposure treatments were all significantly reduced compared with the control, and the population growth coefficients in the LC50♀ × LC50♂ treatments were only 0.32% (A. ipsilon) and 3.35% (A. segetum) that of the control. Furthermore, the flight distance was significantly suppressed from 6.67 km (control) to 0.01 km (LC50) for A. ipsilon, and from 7.39 km (control) to 0.78 km (LC50) for A. segetum. The proportions of robust‐ and medium‐flight individuals of A. ipsilon and A. segetum in exposure treatments were greatly reduced. CONCLUSIONS: Low lethal concentration exposures to chlorantraniliprole can drastically reduce the reproduction and flight performance of A. ipsilon and A. segetum, while inhibiting the production of offspring, suggesting chlorantraniliprole would be an excellent compound for use in combination with food attractants. Chlorantraniliprole has good potential for management of the two long‐range migratory pests tested using an attract‐and‐kill strategy. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A facile benzylic alkylation of indenes and other arenes was developed from readily available primary and secondary alcohols using our newly investigated CCC pincer IrIII catalyst (SNIr−H). Excellent regioselectivity and yield (89 %) of the C3‐alkylated indenes were obtained. Additionally, the challenging sp2C‐alkylation was readily accomplished. This method could be utilized for the synthesis of the analogs of a histamine H1 receptor antagonist and the functional material template molecule, indeno[2,1‐a]indene. A hemilabile IrIII‐dihydride intermediate was proposed based on control experiments and previous density functional theory (DFT) calculations for the borrowing hydrogen mechanism and is key to the success of this IrIII catalyst in the reduction of unactivated multi‐substituted olefin intermediates. [ABSTRACT FROM AUTHOR]

A new class of electrophilic monofluoromethylselenolation reagents, Se‐(fluoromethyl) benzenesulfonoselenoates, has been developed. They can be readily prepared from sodium benzenesulfinates, Se powder and ClCFH2 in one step under mild reaction conditions. Se‐(fluoromethyl) benzenesulfonoselenoates are efficient electrophilic monofluoromethylselenolation reagents for a wide range of nucleophiles including indole, 6‐azaindole, pyrrole, thiophene, electron‐rich arene, aryl boronic acid and alkyne. The monofluoromethylselenolation approach features mild and environmentally friendly reaction conditions, good tolerance of various functional groups, and broad substrate scope. [ABSTRACT FROM AUTHOR]

The emergence of bacterial resistance due to the evolution of microbes under antibiotic selection pressure, and their ability to form biofilm, has necessitated the development of alternative antimicrobial therapeutics. Physical stimulation, as a powerful antimicrobial method to disrupt microbial structure, has been widely used in food and industrial sterilization. With advances in nanotechnology, nanophysical antimicrobial strategies (NPAS) have provided unprecedented opportunities to treat antibiotic‐resistant infections, via a combination of nanomaterials and physical stimulations. In this review, NPAS are categorized according to the modes of their physical stimulation, which include mechanical, optical, magnetic, acoustic, and electrical signals. The biomedical applications of NPAS in combating bacterial infections are systematically introduced, with a focus on their design and antimicrobial mechanisms. Current challenges and further perspectives of NPAS in the clinical treatment of bacterial infections are also summarized and discussed to highlight their potential use in clinical settings. The authors hope that this review will attract more researchers to further advance the promising field of NPAS, and provide new insights for designing powerful strategies to combat bacterial resistance. [ABSTRACT FROM AUTHOR]