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Silacycles have exhibited significant potential for application in the fields of medicinal chemistry, agrochemistry, and materials science. Accordingly, the development of effective methods for synthesizing these compounds has attracted increasing attention. Here, we report an efficient Cu‐catalyzed enantioselective hydrosilylation of arylmethylenecyclopropanes with hydrosilanes, that allows the rapid assembly of various enantioenriched carbon‐ and silicon‐stereogenic silacyclopentanes in good yields with excellent enantioselectivities and diastereoselectivities under mild conditions. Further stereospecific transformation of the Si−H bond on the chiral silicon center expands the diversity of these C‐ and Si‐stereogenic silacyclopentanes. [ABSTRACT FROM AUTHOR]

Organic anodes have emerged as a promising energy storage medium in proton ion batteries (PrIBs) due to their ability to reversibly accommodate non‐metallic proton ions. Nevertheless, the currently available organic electrodes often encounter dissolution issues, leading to a decrease in long‐cycle stability. In addition, the inherent potential of the organic anode is generally relatively high, resulting in low cell voltage of assembled PrIBs (<1.0 V). To address these challenges, a novel long‐period stable, low redox potential biphenylzine derivative, [2,2′‐biphenazine]‐7,7′‐tetraol (BPZT) is explored, from the perspective of molecular symmetry and solubility, in conjunction with the effect of the molecular frontier orbital energy levels on its redox potential. Specifically, BPZT exhibited a low potential of 0.29 V (vs SHE) and is virtually insoluble in 2 m H2SO4 electrolyte during cycling. When paired with MnO2@GF or PbO2 cathodes, the resulting PrIBs achieve cell voltages of 1.07 V or 1.44 V, respectively, and maintain a high capacity retention of 90% over 20000 cycles. Additionally, these full batteries can operate stably at a high mass loading of 10 mgBPZT cm−2, highlighting their potential toward long‐term energy storage applications. [ABSTRACT FROM AUTHOR]

Electron–phonon coupling (EPC) and phonon–phonon scattering (PPS) are at the core of the microscopic physics mechanisms of vast quantum materials. However, to date, there are rarely reports that these two processes can be spatially separated, although they are usually temporally detached with different characteristic lifetimes. Here, by employing ultrafast spectroscopy to investigate the photo‐carrier ultrafast dynamics in a LaCoO3 thin film on a (100) SrTiO3 substrate, intriguing evidence is found that the two interactions are indeed spatially separated. The EPC mainly occurs in the thin film, whereas PPS is largely in the substrate, especially at the several atomic layers near the interface. Across‐interface penetration and decay of optical phonons into acoustic phonons thus naturally occur. An EPC strength λEg = 0.30 is also obtained and an acoustic phonon mode at 45.3 GHz is observed. The finding lays out a cornerstone for future quantum nano device designs. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to explore the application value of shear wave elastography in healthy adults with knee meniscus. Methods: One hundred adult subjects who underwent health checkups at our hospital from December 2022 to February 2023 were selected as research participants. Shear wave elastography was used to evaluate the periphery of the lateral and medial meniscus in both knees. To assess the mean differences in Young's modulus values between male and female groups, a one‐way analysis of variance (ANOVA) and independent samples t‐test were conducted. In addition, a Pearson correlation coefficient test was used to analyze the correlation between the elastic values of the meniscus and age, height, weight, and body mass index (BMI). Results: There were no significant differences in elastic values between the lateral meniscus of the left and right sides or between the medial meniscus of the left and right sides within the same gender group (P >.05). Stiffness values of the medial meniscus were higher in each gender group than those of the lateral meniscus (P <.01). Additionally, males demonstrated higher stiffness values than females (P <.01). As age increased, the Young's modulus of the meniscus increased significantly (r >.75, P <.01). Conclusion: Shear wave elastography can serve as an adjunctive tool to aid in the assessment of knee meniscal elasticity. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) are gaining popularity as advanced energy storage devices that are economical, safe, and use resource‐abundant storage options. In this study, we have synthesized a bipolar phenothiazine organic scaffold known as 3,7‐bis(melaminyl)phenothiazin‐5‐ium iodide (PTDM), which is obtained by undergoing nucleophilic substitution through phenothiazinium tetraiodide hydrate (PTD) and melamine. Electrochemical results indicate that PTDM can act as a high‐potential cathode material for rechargeable AZIBs. In detail, the aqueous PTDM//Zn full cell exhibits a high average voltage of approximate 1.13 V, along with a specific capacity of 118.3 mAh g−1 at 0.1 A g−1. Furthermore, this demonstrated cell displays moderate long‐term cycling stability over 6400 cycles, which is encouraging and suggests potential for developing advanced organic electrode materials for rechargeable AZIBs. [ABSTRACT FROM AUTHOR]

Purpose: To develop a deep learning radiomics of multiparametric magnetic resonance imaging (DLRMM)‐based model that incorporates preoperative and postoperative signatures for prediction of local tumor progression (LTP) after thermal ablation (TA) in hepatocellular carcinoma (HCC). Methods: From May 2017 to October 2021, 417 eligible patients with HCC were retrospectively enrolled from three hospitals (one primary cohort [PC, n = 189] and two external test cohorts [ETCs][n = 135, 93]). DLRMM features were extracted from T1WI + C, T2WI, and DWI using ResNet18 model. An integrative model incorporating the DLRMM signature with clinicopathologic variables were further built to LTP risk stratification. The performance of these models were compared by areas under receiver operating characteristic curve (AUC) using DeLong test. Results: A total of 1668 subsequences and 31,536 multiparametric MRI slice including T1WI, T2WI, and DWI were collected simultaneously. The DLRMM signatures were extracted from tumor and ablation zone, respectively. Ablative margin, multiple tumors, and tumor abutting major vessels were regarded as risk factors for LTP in clinical model. The AUC of DLRMM model were 0.864 in PC, 0.843 in ETC1, and 0.858 in ETC2, which was higher significantly than those in clinical model (p < 0.001). After integrating clinical variable, DLRMM model obtained significant improvement with AUC of 0.870–0.869 in three cohorts (all, p < 0.001), which can provide the risk stratification for overall survival of HCC patients. Conclusions: The DLRMM model is essential to identify LTP risk of HCC patients who underwent TA and may potentially benefit personalized decision‐making. Findings: In this multicenter study that included 417 patients, a deep learning radiomics model was proposed, which achieved high prediction accuracy with AUC of 0.864‐0.858 across one training and two external testing cohorts, and realized successful patient stratification of high and low local recurrence risk. Meaning: The proposed prediction system may help physicians in therapeutic decision making and surveillance strategy selection for hepatocellular carcinoma patients after thermal ablation in clinical practice. [ABSTRACT FROM AUTHOR]

Birefringence, which modulates the polarization of electromagnetic wave, has been commercially developed and widely used in modern photonics. Fostered by high-frequency signal processing and communications, feasible birefringence technologies operating in gigahertz (GHz) range are highly desired. Here, a coherent phonon-induced GHz optical birefringence and its manipulation in SrTiO3 (STO) crystals are demonsrated. With ultrafast laser pumping, the coherent acoustic phonons with low damping are created in the transducer/STO structures. A series of transducer layers are examined and the optimized one with relatively high photon-phonon conversion efficiency, i.e., semiconducting LaRhO3 film, is obtained. The most intriguing finding here is that, by virtue of high sensitivity to strain perturbation of STO, GHz optical birefringence can be induced by the coherent acoustic phonons and the birefringent amplitudes possess crystal orientation dependence. Optical manipulation of both coherent phonons and its induced GHz birefringence by double pump technique are also realized. These findings reveal an alternative mechanism of ultrafast optical birefringence control, and offer prospects for applications in high-frequency acoustic-optics devices. [ABSTRACT FROM AUTHOR]

Purpose: Evaluate the efficacy and safety of triple therapeutic method (Hepatic Aarterial Infusion Chemotherapy—HAIC, lenvatinib and sequential ablation) in the treatment for Advanced Hepatocellular carcinoma (Ad‐HCC). Materials and Methods: From November 2018 to June 2021, data from 150 consecutive Ad‐HCC patients were collected. All patients received HAIC combined with lenvatinib (H‐L group, n = 97) or HAIC combined with lenvatinib and sequential ablation (H‐L‐A group, n = 53). Complications, overall survival (OS), progression‐free survival (PFS) and intrahepatic progression‐free survival (IPFS) were compared between both groups. Results: No significant differences of baseline characteristics were found between groups. The time of median follow‐up was 17.8 months (range, 6.8, 37.6 months). In comparison to the H‐L group, the H‐L‐A group patients showed significantly longer median OS (>30 months vs 13.6 months, respectively; p = 0.010), PFS (12.8 vs. 5.6 months, respectively; p < 0.001), and IPFS (14.6 vs. 6.8 months, respectively; p = 0.002). According to the results from uni‐ and multivariable analyses, we considered α‐fetoprotein and treatment modality as two survival independent prognostic factors. No significant change of the complication incidences was observed between H‐L group and H‐L‐A group (12.4% vs. 11.3%, p = 0.890). Conclusion: Compared to HAIC combined with lenvatinib only, HAIC combined with lenvatinib and sequential ablation was safer and more effective, improving survival outcomes of Ad‐HCC patients. A prospective study will be designed validate the retrospective results. [ABSTRACT FROM AUTHOR]

Asymmetric Hydrosilylation. In their Communication (e202413753), Chuan He et al. report an efficient Cu‐catalyzed asymmetric cascade hydrosilylation protocol, which allows the rapid assembly of carbon‐ and silicon‐stereogenic silacyclopentanes with good to excellent enantioselectivities and diastereoselectivities...By Liexin Wu; Lu Zhang; Jiandong Guo; Jihui Gao; Yang Ding; Jie Ke and Chuan HeReported by Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Catalytic enantioselective hydroxylation of prochiral dihydrosilanes with water is expected to be a highly efficient way to access Si‐chiral silanols, yet has remained unknown up to date. Herein, we describe a strategy for realizing this reaction: using an alkyl bromide as a single‐electron transfer (SET) oxidant for invoking CuII species and chiral multidentate anionic N,N,P‐ligands for effective enantiocontrol. The reaction readily provides a broad range of Si‐chiral silanols with high enantioselectivity and excellent functional group compatibility. In addition, we manifest the synthetic potential by establishing two synthetic schemes for transforming the obtained products into Si‐chiral compounds with high structural diversity. Our preliminary mechanistic studies support a mechanism involving SET for recruiting chiral CuII species as the active catalyst and its subsequent σ‐metathesis with dihydrosilanes. [ABSTRACT FROM AUTHOR]

(111)‐oriented [(SrMnO3)1/(LaMnO3)2]n superlattices with artificial A‐site cation ordering with respect to the compositionally equivalent La2/3Sr1/3MnO3 films with a random distribution of the A‐site dopants are fabricated. It is found that the ferromagnetism and electrical transport properties of La2/3Sr1/3MnO3 films are primarily independent of the degree of A‐site cation ordering, as evidenced by their identical critical temperatures of phase transition. These results may reveal the spontaneous nature of the electronic phase separation, which is key to the colossal magnetoresistance effect in manganites. In contrast, compared to the La2/3Sr1/3MnO3 films, the A‐site ordered (111) superlattices have a tendency to preserve oxygen vacancies inside, making them extremely difficult to be compensated by the post‐annealing process. [ABSTRACT FROM AUTHOR]

The Ni‐catalyzed decarbonylative borylation of (hetero)aryl carboxylic acids with B2cat2 has been achieved without recourse to any additives. This Ni‐catalyzed method exhibits a broad substrate scope covering poorly reactive non‐ortho‐substituted (hetero)aryl carboxylic acids, and tolerates diverse functional groups including some of the groups active to Ni0 catalysts. The key to achieve this decarbonylative borylation reaction is the choice of B2cat2 as a coupling partner that not only acts as a borylating reagent, but also chemoselectively activates aryl carboxylic acids towards oxidative addition of their C(acyl)−O bond to Ni0 catalyst via the formation of acyloxyboron compounds. A combination of experimental and computational studies reveals a detailed plausible mechanism for this reaction system, which involves a hitherto unknown concerted decarbonylation and reductive elimination step that generates the aryl boronic ester product. This mode of boron‐promoted carboxylic acid activation is also applicable to other types of reactions. [ABSTRACT FROM AUTHOR]

This paper proposes an innovative and efficient three-dimensional (3D) autonomous obstacle algorithm for unmanned aerial vehicles (UAVs) which works by generating circular arc trajectories to avoid obstacles. Firstly, information on irregular obstacles is obtained by an onboard detection system; this information is then transformed into standard convex bodies, which are used to generate circular arc avoidance trajectories, and the obstacle avoidance problem is turned into a trajectory tracking strategy. Then, on the basis of the geometric relationship between a UAV and obstacle modeling, the working mechanism of the avoidance algorithm is developed. The rules of obstacle detection, avoidance direction, and the criterion of avoidance success are defined for different obstacle types. Finally, numerical simulations of different obstacle scenarios show that the proposed algorithm can avoid static and dynamic obstacles effectively and can implement obstacle avoidance missions for UAVs well. [ABSTRACT FROM AUTHOR]

A coordination and copolymerization strategy was adopted to synthesize bonded Eu(III) polymer phosphor poly(MMA‐co‐Eu(BTZ)2(Phen)(UA)) (PM‐Eu for short) with methyl methacrylate (MMA) as polymer matrix and Eu‐complex monomer Eu (BTZ)2(Phen)(UA) using azodiisobutyronitrile as initiator. The copolymer PM‐Eu exhibits thermal stability up to 266°C. It also exhibits wide and strong excitation bands from 230 to 380 nm monitored at 612 nm, matching well with the 365 nm of ultraviolet (UV) chip. PM‐Eu displays Eu(III) characteristic peaks at 579, 591, 612, 650, and 700 nm under the excitation of 365 nm of UV light. Meanwhile, it has a fluorescence lifetime of 0.582 ms, and it has a higher quantum yield of 0.672. All the results prove that the polymer PM‐Eu can be applied as a red component for fabrication of near UV‐based white light‐emitting diode (LED). [ABSTRACT FROM AUTHOR]

Acceptorless dehydrogenative coupling (ADC) reactions generally involve a nucleophile (e.g. amine) as a coupling partner. Intriguingly, it has been reported that nitriles could also act as nucleophiles in ADC reactions, achieving the α‐olefination of nitriles with primary or secondary alcohols by employing a manganese or ruthenium pincer complex as the catalyst, respectively. Although different mechanisms have been postulated for the two catalytic systems, the results of our DFT mechanistic study, reported herein, have allowed us to propose a unified mechanism to account for both nitrile α‐olefinations. The reactions take place in four stages, namely alcohol dehydrogenation, nitrile activation to generate a nucleophilic metal species, coupling of an aldehyde or ketone with the metal species to form a C−C bond and to transfer a nitrile (Cα−)H atom to the carbonyl group, and dehydration by transferring the protonic (N−)H to the hydroxy group. A notable feature of the coupling stage is the activation of water or alcohol to give an intermediate featuring an OH−‐ or OR−‐like group that activates a nitrile Cα−H bond. Moreover, the mechanism can even be applied to the base (KOtBu, modeled by the (KOtBu)4 cluster)‐catalyzed Knoevenagel condensation of nitriles with ketones, which further indicates the generality of the mechanism and the resemblance of the metal pincer complexes to the (KOtBu)4 base. We expect these in‐depth mechanistic insights and the finding of the resemblance of the metal pincer complexes to the (KOtBu)4 cluster could assist the development of new ADC reactions. A unified mechanism is proposed to account for nitrile α‐olefinations with primary/secondary alcohols catalyzed by Mn/Ru pincer complexes (see scheme). Nitrile is activated by a nucleophilic metal species through metal–ligand cooperation. Coupling between the aldehyde/ketone and metal species involves the activation of water/alcohol to a species featuring an OH−/OR−‐like group that activates the nitrile Cα−H bond. The mechanism can also be applied to the KOtBu‐catalyzed Knoevenagel condensation of nitrile with ketone. [ABSTRACT FROM AUTHOR]

Abstract: Nanometer‐wide graphene nanoribbons can be synthesized from halogen aromatics through multistep on‐surface reactions, but the catalytic role of extrinsic transition‐metal atoms in these reactions are still to be explored. Here by low‐temperature scanning tunneling microscopy, we investigated the on‐surface synthesis of graphene nanoribbons from 10,10′‐dibromo‐9,9′‐bianthryl precursors in the presence of Ni atoms. Ni atoms not only act as catalysts in debromination and lead to the formation of an organometallic intermediate at 300 K, but also prompt the fusion reaction between graphene nanoribbons at 673 K. Our work demonstrates a more efficient way to fabricate fused graphene nanoribbons. [ABSTRACT FROM AUTHOR]

Abstract: Titanium catalysis generally prefers redox‐neutral mechanisms. Yet it has been reported that titanium could promote bond formations in a way similar to reductive elimination. Accordingly, redox catalytic cycles involving TiIV/TiII cycling have been considered. By studying, as an example, the carboamination of alkynes with alkenes and azobenzene catalyzed by the [TiIV]=NPh imido complex, we performed DFT computations to gain an understanding of how the “abnormal” catalysis takes place, thereby allowing us to clarify whether the catalysis really follows TiIV/TiII redox mechanisms. The reaction first forms an azatitanacyclohexene by alkyne addition to the [TiIV]=NPh bond, followed by alkene insertion. The azatitanacyclohexene can either undergo Cα−Cγ coupling, to afford bicyclo[3.1.0]imine, or β‐H elimination, to yield a [TiIV]−H hydride, which then undergoes Cα=Cβ or Cγ=Cδ insertion to give an α,β‐ or β,γ‐unsaturated imine, respectively. Both the geometric and electronic structures indicate that the catalytic cycles proceed through redox‐neutral mechanisms. The alternative redox mechanisms (e.g., by N−H or C−H reductive elimination) are substantially less favorable. We concluded that electronically, the TiIV catalysis intrinsically favors the redox‐neutral mechanism, because a redox pathway would involve TiII structures either in the triplet ground state or in the high‐lying open‐shell singlet state, but the involvement of triplet TiII structures is spin‐forbidden and that of singlet TiII structures is energetically disadvantageous. [ABSTRACT FROM AUTHOR]

Hydroalkoxylations of terminal alkynes with methanol, catalyzed by 8-quinolinolato- and dipyrrinato-ligated RhI complexes, afford anti-Markovnikov (Z)- and (E)-enol ethers, respectively. Herein we performed a DFT study to gain insight into the mechanisms of the two reactions, aiming at understanding why and how the two ligands differ. Of the two possible mechanisms, namely, Cβ-HT and Rh-HT, characterized by a RhI Fisher carbene and vinyl RhIII–H hydride complex, respectively, the hydroalkoxylation with 8-quinolinolato prefers the Cβ-HT mechanism, while that with dipyrrinato favors the Rh-HT mechanism. The root cause for the mechanistic difference is that the O atom in 8-quinolinolato, due to its large electronegativity and exposure, is more favorable than the N atom in dipyrrinato in stabilizing the protic hydrogen as methanol undergoes a 1,3-addition, thus the addition in the former is much easier than that in the latter. Consequently, the addition in the hydroalkoxylation with dipyrrinato controls the reaction selectivity, giving the (E)-enol ether. In contrast, the selectivity of the hydroalkoxylation with 8-quinolinolato is determined by the RhI Fisher carbene to undergo a 1,2-hydrogen transfer, leading to the (Z)-enol ether. Furthermore, a DMA solvent molecule substantially facilitates the methanol addition in the reaction with dipyrrinato but not in the reaction with 8-quinolinolato. [ABSTRACT FROM AUTHOR]

Keywords: borylation; carboxylic acid activation; decarbonylative cross-coupling; DFT studies; nickel catalysis EN borylation carboxylic acid activation decarbonylative cross-coupling DFT studies nickel catalysis 1 1 1 11/02/21 20211108 NES 211108 B Borylation b The activation of aryl carboxylic acids by diboron reagents towards nickel-catalyzed direct decarbonylative borylation is reported by Xiaotai Wang, Weiping Su et al. in their Research Article on page 24510. Borylation, carboxylic acid activation, decarbonylative cross-coupling, DFT studies, nickel catalysis Frontispiece: Activation of Aryl Carboxylic Acids by Diboron Reagents towards Nickel-Catalyzed Direct Decarbonylative Borylation. [Extracted from the article]

Compared to their parent materials, oxygen vacancy (VO)–ordered phases of complex oxides exhibit distinct physical properties and show great potential in multifunctional devices. With the expected unique behaviors, however, most of the VO‐ordered oxide films are extremely difficult to synthesize due to their thermodynamic instabilities. Herein, using LaCoOx as an example, the synthesis of large‐scale monophased VO‐ordered LaCoO2.67 and LaCoO2.5 films is realized by annealing as‐grown perovskite LaCoO3 films in vacuum with a special heating method. Their macroscopic properties, including the magnetic and electric transport and optical properties, are measured. It is demonstrated that the functionalities of LaCoOx films can be manipulated by tuning the concentration and ordering of the VO. The method in this work can be applied to fabricate a wide range of VO‐ordered oxide films. [ABSTRACT FROM AUTHOR]

Electron–phonon coupling (EPC) and phonon–phonon scattering (PPS) are at the core of the microscopic physics mechanisms of vast quantum materials. However, to date, there are rarely reports that these two processes can be spatially separated, although they are usually temporally detached with different characteristic lifetimes. Here, by employing ultrafast spectroscopy to investigate the photo‐carrier ultrafast dynamics in a LaCoO3 thin film on a (100) SrTiO3 substrate, intriguing evidence is found that the two interactions are indeed spatially separated. The EPC mainly occurs in the thin film, whereas PPS is largely in the substrate, especially at the several atomic layers near the interface. Across‐interface penetration and decay of optical phonons into acoustic phonons thus naturally occur. An EPC strength λEg = 0.30 is also obtained and an acoustic phonon mode at 45.3 GHz is observed. The finding lays out a cornerstone for future quantum nano device designs. [ABSTRACT FROM AUTHOR]

The article discusses ore-forming material sources of Liaotun gold deposit in Bama County, Northwestern Guangxi, China. Topics carbonates of carboniferous and Permian system found in the strata and rocks of the ore field, gold ore bodies containing fine-medium grained lithic quartz greywacke and sandstone cataclasite, and Liaotun gold derived from clastic rocks of middle Triassic series.

Birefringence, which modulates the polarization of electromagnetic wave, has been commercially developed and widely used in modern photonics. Fostered by high-frequency signal processing and communications, feasible birefringence technologies operating in gigahertz (GHz) range are highly desired. Here, a coherent phonon-induced GHz optical birefringence and its manipulation in SrTiO3 (STO) crystals are demonsrated. With ultrafast laser pumping, the coherent acoustic phonons with low damping are created in the transducer/STO structures. A series of transducer layers are examined and the optimized one with relatively high photon-phonon conversion efficiency, i.e., semiconducting LaRhO3 film, is obtained. The most intriguing finding here is that, by virtue of high sensitivity to strain perturbation of STO, GHz optical birefringence can be induced by the coherent acoustic phonons and the birefringent amplitudes possess crystal orientation dependence. Optical manipulation of both coherent phonons and its induced GHz birefringence by double pump technique are also realized. These findings reveal an alternative mechanism of ultrafast optical birefringence control, and offer prospects for applications in high-frequency acoustic-optics devices. [ABSTRACT FROM AUTHOR]