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Background and Aim: Primary biliary cholangitis (PBC) is a chronic autoimmune cholangiopathy, characterized by the presence of some autoantibodies in the serum. This study aimed to evaluate the clinical significance of AMA‐M2, anti‐gp210 and anti‐sp100 antibody levels detected by multiplex bead‐based flow fluorescent immunoassay (MBFFI) in PBC. Methods: This study cohort included 238 PBC patients, 81 autoimmune hepatitis (AIH) patients, 62 systemic lupus erythematosus (SLE) patients, and 118 healthy controls. Serum AMA‐M2, anti‐gp210 and anti‐sp100 antibody were detected by MBFFI and immunoblotting assay (IBT). The relationship between three antibody levels and cirrhosis, liver function, cholestasis markers and therapeutic effect to ursodesoxycholic acid (UDCA) was evaluated in PBC. Results: MBFFI were presented good coincidence rate (87.39%–95.38%) with IBT. The level of AMA‐M2, anti‐gp210 and anti‐sp100 antibodies in PBC patients were higher than other disease group and healthy controls (p ＜.01). When compared with the healthy controls group, the AUC of AMA‐M2, anti‐gp210 and anti‐sp100 antibodies were 0.9245, 0.7619, and 0.6789, respectively. In addition, gp210 antibody levels have diagnostic value in patients with liver cirrhosis (AUC: 0.7567). We found that when combine detect these three antibodies, the sensitivity was higher than individually detection. High level of serum anti‐gp210 antibody could be related to worse liver function and more severe cholestasis in PBC patients. Moreover, serum antibody levels may decrease or remained flat in patients who responded well to UDCA. Conclusion: The detection of AMA‐M2, anti‐gp210 and anti‐sp100 antibody levels by MBFFI showed good performance in the diagnosis of PBC. Serum anti‐gp210 antibody level is related to cirrhosis, poor liver function and severe cholestasis in PBC. [ABSTRACT FROM AUTHOR]

Deep learning has achieved unprecedented success in recent years. This approach essentially uses the composition of nonlinear functions to model the complex relationship between input features and output labels. However, a comprehensive theoretical understanding of why the hierarchical layered structure can exhibit superior expressive power is still lacking. In this paper, we provide an explanation for this phenomenon by measuring the approximation efficiency of neural networks with respect to discontinuous target functions. We focus on deep neural networks with rectified linear unit (ReLU) activation functions. We find that to achieve the same degree of approximation accuracy, the number of neurons required by a single‐hidden‐layer (SHL) network is exponentially greater than that required by a multi‐hidden‐layer (MHL) network. In practice, discontinuous points tend to contain highly valuable information (i.e., edges in image classification). We argue that this may be a very important reason accounting for the impressive performance of deep neural networks. We validate our theory in extensive experiments. [ABSTRACT FROM AUTHOR]

Early‐stage photoaging is characterized by skin laxity and wrinkling, which are mainly attributable to the ultraviolet (UV) irradiation‐mediated imbalance between matrix metalloproteinase (MMP) production and collagen degradation. Injectable platelet‐rich fibrin (i‐PRF) is a novel blood concentrate with potential effects on photoaging. Over the past few decades, platelet‐rich plasma (PRP) has been widely researched and used in different clinical fields as a first‐generation platelet concentrate. The aim of this study was to compare the antiphotoaging effects of i‐PRF in UVA‐irradiated human dermal fibroblasts with those of PRP by examining cell proliferation, migration and apoptosis, ROS generation, MMP‐1 and collagen I levels. The activation of the TGF‐β/Smad signaling pathway by i‐PRF and PRP was also investigated using western blotting. The results showed that i‐PRF was more effective than PRP in promoting cell proliferation and migration. Moreover, i‐PRF reduced ROS generation and cell apoptosis more effectively than PRP. With respect to the mechanism of collagen I upregulation, stronger stimulation of the TGF‐β/Smad signaling pathway and greater suppression of MMP‐1 expression were achieved by i‐PRF than by PRP. Our results suggest that i‐PRF can be a promising substitute for PRP in alleviating UVA‐induced photoaging and should be explored further for its anti‐photoaging properties. [ABSTRACT FROM AUTHOR]

Studies have shown that facial recognition among racial groups exhibits not only an other‐race effect but also an other‐ethnicity effect within the same racial group. To explore differences in facial recognition and visual scanning patterns due to the other‐ethnicity effect, behavioural and eye‐movement data were used to investigate the other‐ethnicity effect in the facial perception of Tibetan and Han Chinese individuals and whether the visual scanning patterns varied between them. Behavioural data revealed an other‐ethnicity effect on facial recognition of Tibetan and Han individuals. Eye‐movement data indicated that Tibetan and Han individuals fixated more on the eye and mouth regions when recognising Han faces and on the eye and nose regions when recognising Tibetan faces. The other‐ethnicity effect appeared to influence facial recognition in Tibetan and Han individuals, who adopted similar visual scanning patterns when scanning the faces of individuals of their own ethnicity and those of other ethnicities. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A new family of dibenzoullazine derivatives was synthesized through 1,3‐dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by oxidation. The benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods. [ABSTRACT FROM AUTHOR]

The reissner lamprey Lethenteron reissneri, belonging to the class Cyclostomata, serves as a bridge between invertebrates and jawed vertebrates, and is considered the sister group of jawed vertebrates. However, despite this evolutionary significance, the genetic mechanisms underlying the adaptive evolution of the lamprey lineage remain unclear. Here, we assembled a 1.06 Gb chromosome‐level draft genome of L. reissneri, with 72 chromosomes (ranging in length from 4.5 Mb to 25.9 Mb) and a scaffold N50 length of 13.23 Mb. Genome quality comparisons revealed that the reissner lamprey genome has higher completeness and contiguity than the previously published sea lamprey and Japanese lamprey genomes. Moreover, reissner lamprey, sea lamprey, and Japanese lamprey species share similar transposable element profiles and Hox gene cluster compositions, suggesting that a burst of transposable element activity and whole genome duplication occurred before their divergence. Additionally, the Lip gene copy numbers, which have been studied for their functions in the host defence system, were found to be expanded uniquely in lamprey lineages, suggesting key roles for these genes in lamprey evolution and adaptation. We also identified two neural‐related genes, Nrn1 and Unc13a, with copy number expansions in jawed vertebrates, which may be functionally relevant to the origin of lamprey brains. Hence, this study not only provides the first chromosome‐level reference genome for Cyclostomata, but also highlights features of the unique biology and adaptive evolution of the lamprey lineage. [ABSTRACT FROM AUTHOR]

A facile approach to assemble catalase‐like photosensitizing nanozymes with a self‐oxygen‐supplying ability was developed. The process involved Fe3+‐driven self‐assembly of fluorenylmethyloxycarbonyl (Fmoc)‐protected amino acids. By adding a zinc(II) phthalocyanine‐based photosensitizer (ZnPc) and the hypoxia‐inducible factor 1 (HIF‐1) inhibitor acriflavine (ACF) during the Fe3+‐promoted self‐assembly of Fmoc‐protected cysteine (Fmoc‐Cys), the nanovesicles Fmoc‐Cys/Fe@Pc and Fmoc‐Cys/Fe@Pc/ACF were prepared, which could be disassembled intracellularly. The released Fe3+ could catalyze the transformation of H2O2 enriched in cancer cells to oxygen efficiently, thereby ameliorating the hypoxic condition and promoting the photosensitizing activity of the released ZnPc. With an additional therapeutic component, Fmoc‐Cys/Fe@Pc/ACF exhibited higher in vitro and in vivo photodynamic activities than Fmoc‐Cys/Fe@Pc, demonstrating the synergistic effect of ZnPc and ACF. [ABSTRACT FROM AUTHOR]

A facile approach to assemble catalase‐like photosensitizing nanozymes with a self‐oxygen‐supplying ability was developed. The process involved Fe3+‐driven self‐assembly of fluorenylmethyloxycarbonyl (Fmoc)‐protected amino acids. By adding a zinc(II) phthalocyanine‐based photosensitizer (ZnPc) and the hypoxia‐inducible factor 1 (HIF‐1) inhibitor acriflavine (ACF) during the Fe3+‐promoted self‐assembly of Fmoc‐protected cysteine (Fmoc‐Cys), the nanovesicles Fmoc‐Cys/Fe@Pc and Fmoc‐Cys/Fe@Pc/ACF were prepared, which could be disassembled intracellularly. The released Fe3+ could catalyze the transformation of H2O2 enriched in cancer cells to oxygen efficiently, thereby ameliorating the hypoxic condition and promoting the photosensitizing activity of the released ZnPc. With an additional therapeutic component, Fmoc‐Cys/Fe@Pc/ACF exhibited higher in vitro and in vivo photodynamic activities than Fmoc‐Cys/Fe@Pc, demonstrating the synergistic effect of ZnPc and ACF. [ABSTRACT FROM AUTHOR]

Introduction: Generalized tonic‐clonic seizure (GTCS) is a condition that is characterized by generalized spike‐wave discharge in bilateral cerebral hemispheres during the seizure. Although previous neuroimaging studies revealed functional abnormalities in the brain activities of children with GTCS, the topological alterations in whole‐brain networks remain poorly understood. Methods: The present study used graph theory to investigate the topological organization of functional networks in 13 GTCS children and 30 age‐matched healthy controls. Results: We found that both groups exhibited a small‐world topology of the functional network. However, children with GTCS showed a significant decrease in nodal local efficiency and clustering coefficient in some key nodes compared with the controls. The connections within the default mode network (DMN) were decreased significantly, and the internetwork connections were increased significantly. The altered topological properties may be an effect of chronic epilepsy. As a result, the optimal topological organization of the functional network was disrupted in the patient group. Notably, clustering coefficient and nodal local efficiency in the bilateral temporal pole of the middle temporal gyrus negatively correlated with the epilepsy duration. Conclusion: These results suggest that the bilateral temporal pole plays an important role in reflecting the effect of chronic epilepsy on the topological properties in GTCS children. The present study demonstrated a disrupted topological organization in children with GTCS. These findings provide new insight into our understanding of this disorder. [ABSTRACT FROM AUTHOR]

Cycloheptatrienyl (tropyl) molecules are representative non‐alternant hydrocarbons that offer interesting chemistry because of their unique structures and properties. However, there have been a limited number of polycyclic aromatic tropyl cations and radicals reported in the literature. Herein, we report the synthesis of a series of azahomocorannulene derivatives, where the key reactions are a 1,3‐dipolar cycloaddition of polycyclic aromatic azomethine ylides with dibenzotropone and a subsequent palladium‐catalyzed cyclization. X‐ray diffraction analysis revealed that the obtained azahomocorannulenyl cation and radical adopt planar structures and exhibit unique packing structures. Their electronic and optical properties were investigated experimentally and theoretically to reveal their aromatic character. [ABSTRACT FROM AUTHOR]

Cycloheptatrienyl (tropyl) molecules are representative non‐alternant hydrocarbons that offer interesting chemistry because of their unique structures and properties. However, there have been a limited number of polycyclic aromatic tropyl cations and radicals reported in the literature. Herein, we report the synthesis of a series of azahomocorannulene derivatives, where the key reactions are a 1,3‐dipolar cycloaddition of polycyclic aromatic azomethine ylides with dibenzotropone and a subsequent palladium‐catalyzed cyclization. X‐ray diffraction analysis revealed that the obtained azahomocorannulenyl cation and radical adopt planar structures and exhibit unique packing structures. Their electronic and optical properties were investigated experimentally and theoretically to reveal their aromatic character. [ABSTRACT FROM AUTHOR]

Objective: To analyse clinical information from a cohort of 877 cochlear implant (CI) surgeries performed in patients with inner ear malformations and report our experience with this procedure. Methods: Clinical information on patients with inner ear malformation who underwent CI surgery in our department from January 2010 to April 2017 was analysed. Results: Seven hundred and fifty‐four CI surgeries (86.0%) were uneventful but cerebrospinal fluid gusher occurred during surgery in 118 cases (13.5%). Not including the patients lost to follow‐up, postoperative Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores were collected from 13 patients with common cavity deformity, 38 with IP‐I, 11 with hypoplasia, 13 with IP‐III, 285 with IP‐II and 43 with cochlear nerve deficiency. The mean CAP scores were 2.55, 3.39, 3.45, 3.77, 3.98, 2.95 and 2.90, and the mean SIR scores were 1.54, 3.68, 3.72, 3.54, 3.80, 2.31 and 2.32. Patients with common cavity deformity who underwent surgery using the traditional facial recess approach or transmastoid slotted labyrinthotomy approach had significantly better post‐activation scores on the CAP, SIR and Meaningful Auditory Integration Scale/Infant‐Toddler Meaningful Auditory Integration Scale, with no significant differences between the two approaches. Conclusion: The traditional facial recess approach can be successful, and several approaches may be used for electrode insertion and gusher control in patients with a severe deformity, particularly common cavity deformity and IP‐III. A gusher was the most common intraoperative finding and occurred most often in patients with IP‐III. Careful consideration of the type of electrode used is important. [ABSTRACT FROM AUTHOR]

Clinical translation of curcumin has been highly obstructed by the rapid degradation and poor tissue absorption of this agent. Herein, we report on the generation of supramolecular curcumin nanoagents through amino acid coordination driven self‐assembly to simultaneously increase the biological stability and tumor accumulation of curcumin. The biological stability of curcumin was significantly improved both through coordination and through molecular stacking. The sizes of these nanoagents can be readily manipulated to facilitate tumor accumulation. These favorable therapeutic features, together with high drug‐loading capacities and responses to pH and redox stimuli, substantially enhanced the antitumor activity of curcumin without discernible side effects. Hence, supramolecular curcumin nanoagents may hold promise in moving forward the clinical application of curcumin as an effective anticancer drug. Special agents on the job: Supramolecular curcumin nanoagents were fabricated by amino acid coordination driven self‐assembly (see picture). The biological stability of curcumin was significantly improved through both coordination and molecular stacking in the nanoagents, the size of which could be readily manipulated. These favorable therapeutic features substantially enhanced the antitumor activity of curcumin without discernible side effects. [ABSTRACT FROM AUTHOR]

Clinical translation of curcumin has been highly obstructed by the rapid degradation and poor tissue absorption of this agent. Herein, we report on the generation of supramolecular curcumin nanoagents through amino acid coordination driven self‐assembly to simultaneously increase the biological stability and tumor accumulation of curcumin. The biological stability of curcumin was significantly improved both through coordination and through molecular stacking. The sizes of these nanoagents can be readily manipulated to facilitate tumor accumulation. These favorable therapeutic features, together with high drug‐loading capacities and responses to pH and redox stimuli, substantially enhanced the antitumor activity of curcumin without discernible side effects. Hence, supramolecular curcumin nanoagents may hold promise in moving forward the clinical application of curcumin as an effective anticancer drug. [ABSTRACT FROM AUTHOR]

The significance of neuronal discharge symmetry lies in its reflection of the stability and orderliness within the neuron's activity. This symmetry is correlated with various issues, including the biophysical properties within neurons, network structures, and synaptic transmission. Memristors are highly analogous to neuronal synapses due to their unique memory properties, allowing them to emulate biological neural synapses. In this work, a memristor is employed into the Hindmarsh‐Rose (HR) neuron as a synapse for the construction of a memristive HR neuron. Accompanied with the introducing of the absolute value and signum function, the derived neurons exhibit complex coexisting symmetric firing patterns. The phenomenon of symmetric firing can effectively simulate the depolarization and hyperpolarization processes of neurons, providing a new approach to study the diversity of the brain. [ABSTRACT FROM AUTHOR]

Abstract: An annulated 1,3,2,5‐diazadiborinine with 14 π electrons has been synthesized and fully characterized. Experimental and computational studies revealed that this compound features a rather small HOMO–LUMO gap, which leads to enhanced reactivity towards small molecules. Thus, the 1,3,2,5‐diazadiborinine readily cleaves the H−H bond of dihydrogen and an N−H bond of ammonia under mild conditions. Moreover, it reacts with 2,6‐dimethylphenylisonitrile in a [4+1] cycloaddition at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: One‐electron oxidation of 1,4,2,5‐diazadiborinine 1 has been studied. While the reaction of 1 a bearing phenyl groups on the B atoms with AgAl{OC(CF3)3}4 afforded a complex mixture, the same oxidation reaction with 1 b featuring bulky mesityl substituents on the B atoms rendered the corresponding cation radical 2 b as an isolable species. X‐ray diffraction analysis, EPR spectroscopy, and DFT calculations of 2 b revealed the delocalization of the unpaired electron over the entire π‐system of 2 b, as well as a large spin density (0.76 in total) on the two equivalent boron atoms. The chemical trapping reaction of 2 b with p‐benzoquinone and triphenyltin hydride afforded the dicationic species 3 containing two newly formed B−O bonds and the monocationic product 2b‐H containing a B−H bond, respectively, thus confirming the boron‐centered radical reactivity of 2 b. [ABSTRACT FROM AUTHOR]

Abstract: Determination of molecular structural parameters of hydrophobic cholesterol–naphthalimide conjugates for water binding capabilities as well as their moisture‐sensitive supramolecular self‐assembly were revealed. Water binding was a key factor in leading trace water‐induced crystallization against gelation in apolar solvent. Ordered water molecules entrapped in self‐assembly arrays revealed by crystal structures behave as hydrogen‐bonding linkers to facilitate three‐dimensional growth into crystals rather than one‐dimensional gel nanofibers. Water binding was also reflected on the supramolecular chirality inversion of vesicle self‐assembly in aqueous media via heating‐induced dehydration. Structural parameters that favor water binding were evaluated in detail, which could help rationally design organic building units for advancing soft materials, crystal engineering, and chiral recognition. [ABSTRACT FROM AUTHOR]

Abstract: An annulated 1,3,2,5‐diazadiborinine with 14 π electrons has been synthesized and fully characterized. Experimental and computational studies revealed that this compound features a rather small HOMO–LUMO gap, which leads to enhanced reactivity towards small molecules. Thus, the 1,3,2,5‐diazadiborinine readily cleaves the H−H bond of dihydrogen and an N−H bond of ammonia under mild conditions. Moreover, it reacts with 2,6‐dimethylphenylisonitrile in a [4+1] cycloaddition at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: One‐electron oxidation of 1,4,2,5‐diazadiborinine 1 has been studied. While the reaction of 1 a bearing phenyl groups on the B atoms with AgAl{OC(CF3)3}4 afforded a complex mixture, the same oxidation reaction with 1 b featuring bulky mesityl substituents on the B atoms rendered the corresponding cation radical 2 b as an isolable species. X‐ray diffraction analysis, EPR spectroscopy, and DFT calculations of 2 b revealed the delocalization of the unpaired electron over the entire π‐system of 2 b, as well as a large spin density (0.76 in total) on the two equivalent boron atoms. The chemical trapping reaction of 2 b with p‐benzoquinone and triphenyltin hydride afforded the dicationic species 3 containing two newly formed B−O bonds and the monocationic product 2b‐H containing a B−H bond, respectively, thus confirming the boron‐centered radical reactivity of 2 b. [ABSTRACT FROM AUTHOR]

Abstract: Determination of molecular structural parameters of hydrophobic cholesterol–naphthalimide conjugates for water binding capabilities as well as their moisture‐sensitive supramolecular self‐assembly were revealed. Water binding was a key factor in leading trace water‐induced crystallization against gelation in apolar solvent. Ordered water molecules entrapped in self‐assembly arrays revealed by crystal structures behave as hydrogen‐bonding linkers to facilitate three‐dimensional growth into crystals rather than one‐dimensional gel nanofibers. Water binding was also reflected on the supramolecular chirality inversion of vesicle self‐assembly in aqueous media via heating‐induced dehydration. Structural parameters that favor water binding were evaluated in detail, which could help rationally design organic building units for advancing soft materials, crystal engineering, and chiral recognition. [ABSTRACT FROM AUTHOR]

Deprotonation of 1‐mesityl‐4,5‐diphenyl‐2‐imidazole 1 with nBuLi, followed by salt metathesis reaction with GeCl2·dioxane complex, led to the formation of the chlorogermyliumylidene 2 bearing two Ge–Cl units, which has been isolated and fully characterized by standard spectroscopic and X‐ray diffraction analysis. Structural and NMR spectroscopic data as well as computational studies revealed that the positive charge mainly resides on the Ge atom between two nitrogen atoms. Reduction of 2 with an excess amount of lithium metal resulted in Ge–Ge bond formation concomitant with elimination of one of the Ge atoms of 2, to give rise to the digermylenedilithium compound 3 involving intramolecular coordination of the imines and the lone pairs to the Li atoms. [ABSTRACT FROM AUTHOR]

Diverse skeletal transformations of 1,4,2-diazaboroles through ring expansion, photoisomerization, and retrocyclization led to the isolation of various B,N-dihydroindole (compounds 3 and 6), 1,3-azaborolidin-2-imine (compound 7), and 1,4,2-diazaborol-3-imine derivatives (compound 11). [ABSTRACT FROM AUTHOR]

Diverse skeletal transformations of 1,4,2-diazaboroles through ring expansion, photoisomerization, and retrocyclization led to the isolation of various B,N-dihydroindole (compounds 3 and 6), 1,3-azaborolidin-2-imine (compound 7), and 1,4,2-diazaborol-3-imine derivatives (compound 11). [ABSTRACT FROM AUTHOR]

A zwitterionic boraalkenyl boronium 3 was synthesized by reduction of cyclic (alkyl)(amino)carbene (cAAC) and trimethylphosphine (PMe3)-coordinated tetrabromodiborane 2 with KC8 in the presence of PMe3. Further reduction of 3 led to the formation of neutral allenic diborene 4. X-ray diffraction and computational studies revealed that 4 features the cumulated C=B and B=B double bonds. The reaction of 4 with four isonitrile molecules afforded a heterocycle 5 with the B2C3 five-membered ring, via a complete scission of the B=B bond of 4. [ABSTRACT FROM AUTHOR]

Metal‐Organic frameworks (MOFs) have the advantages of high porosity, angstrom‐scale pore size, and unique structure. In this work, a kind of MOFs, UiO‐66 and its derivatives (including aminated UiO‐66‐(NH2)2 and sulfonated UiO‐66‐(NH‐SAG)2), were constructed on the inner surface of solid‐state nanopores for ultra‐selective proton transport. UiO‐66 and UiO‐66‐(NH2)2 nanocrystal particles were in‐situ grown at the orifice of glass nanopores firstly, which were used to investigate the ionic current responses in LiCl and HCl solutions when the monovalent anions (Cl−) were unchanged. Compared with UiO‐66‐modifed nanopores, the aminated MOFs modification (UiO‐66‐(NH2)2) can improve the proton selectivity obviously. However, when the UiO‐66‐(NH‐SAG)2 nanopore is prepared by further post‐modification with sulfo‐acetic acid, lithium ions can hardly pass through the channel, and the interaction between protons and sulfonic acid groups can promote the transport of protons, thus achieving ultra‐high selectivity to protons. This work provides a new way to achieve sub‐nanochannels with high selectivity, which can widely be used in ion separation, sensing and energy conversion. [ABSTRACT FROM AUTHOR]

The reactivity of diazadiphosphapentalene 1 towards various substrates was investigated. Reaction of 1 with ammonia-borane resulted in transfer hydrogenolysis concomitantly with the cleavage of a P-N bond. By treatment of 1 with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), oxidation took place at one of the phosphorus atoms of 1, and a PV/PIII mixed-valence derivative was isolated. At the same time, it was demonstrated that only one of the phosphorus atoms in 1 behaves as an electron donor for electrophiles and Lewis acids. The former afforded an intramolecularly coordinated phosphine-phosphenium species, whereas the latter demonstrates the ligand property of 1. UV irradiation induced rearrangement of 1 into another example of another diazadiphosphapentalene. [ABSTRACT FROM AUTHOR]

Reactions of the amidinate-stabilized silicon(II) bis(trimethylsilyl)amide [LSiN(SiMe3)2], {L = PhC(N tBu)2, 1} with a stiochiometric amount of elemental sulfur, selenium and tellurium afforded the first stable silanechalcogenones comprising an acyclic amido substituent [L{N(SiMe3)2}Si=E] {E = S ( 2), Se ( 3) or Te ( 4)}. All compounds were characterized by X-ray crystallography and multinuclear NMR spectroscopy. The results illustrate that these compounds possess some silicon-chalcogen double bond character. [ABSTRACT FROM AUTHOR]

BACKGROUND The postharvest life of fresh-cut apple slices is limited by browning on cut surfaces. Dipping in halide salt solutions was examined for their inhibition of surface browning on 'Granny Smith' apple slices and the effects on biochemical factors associated with browning. RESULTS Delay in browning by salts was greatest with chloride = phosphate > sulfate > nitrate with no difference between sodium, potassium and calcium ions. The effectiveness of sodium halides on browning was fluoride > chloride = bromide > iodide = control. Polyphenol oxidase ( PPO) activity of tissue extracted from chloride- and fluoride-treated slices was not different to control but when added into the assay solution, NaF > NaCl both showed lower PPO activity at pH 3-5 compared to control buffer. The level of polyphenols in treated slices was NaF > NaCl > control. Addition of chlorogenic acid to slices enhanced browning but NaCl and NaF counteracted this effect. There was no effect of either halide salt on respiration, ethylene production, ion leakage, and antioxidant activity. CONCLUSION Dipping apple slices in NaCl is a low cost treatment with few impediments to commercial use and could be a replacement for other anti-browning additives. The mode of action of NaCl and NaF is through decreasing PPO activity resulting in reduced oxidation of polyphenols. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

An isolable phenylborylene species supported by two oxazol-2-ylidene ligands was synthesized and structurally characterized. Computational studies revealed the presence of lone-pair electrons on the boron atom in this molecule; therefore, there are eight electrons around the three-coordinate boron center. The nucleophilic property was confirmed by the reactions with trifluoromethanesulfonic acid and [(thf)Cr(CO)5], which gave the corresponding conjugate acid and a chromium-borylene complex, respectively. [ABSTRACT FROM AUTHOR]

An isolable phenylborylene species supported by two oxazol-2-ylidene ligands was synthesized and structurally characterized. Computational studies revealed the presence of lone-pair electrons on the boron atom in this molecule; therefore, there are eight electrons around the three-coordinate boron center. The nucleophilic property was confirmed by the reactions with trifluoromethanesulfonic acid and [(thf)Cr(CO)5], which gave the corresponding conjugate acid and a chromium-borylene complex, respectively. [ABSTRACT FROM AUTHOR]

The vehicle suspension system is considered to have tremendous potential in energy harvesting and to be applicable for improving the efficiency of energy use of the vehicle. A novel piezoelectric energy harvester (PEH) with noncontact magnetic force has the feature of low friction loss and is designed based on the vibration characteristic of the suspension system. The research comprises two main components: the motion conversion component and the energy conversion component. A screw‐nut mechanism that can convert linear vibration between the vehicle body and the wheel into rotational motion is used as the motion conversion component. The energy conversion component is a core component of the PEH; its function is to convert rotational energy into electrical energy through noncontact magnetic force and piezoelectric effect. The magnetic excitation model's credibility and the modeling method's feasibility are verified by experiment and simulation. Through vehicle field tests, the influence of the driving speed, road surface roughness, and cargo state on the harvested power is obtained. Driving on a random road, the maximum of the generated power is 24.28 W, at 60 km/h, under the laden state. Driving on a pulse road, the harvested power is 3346 W, at 30 km/h, under the unladen state. It is indicated that the PEH is a promising and practical option for harvesting energy for the vehicle's suspension system. [ABSTRACT FROM AUTHOR]

The syntheses and structures of heteroleptic germanium(II) and tin(II) chlorides supported by anionic ligands derived from 2,3-dimethyl-1,4-diaza-1,3-butadiene are described. The reaction of ArN=C(Me)C(Me)=NAr ( L, Ar = 2,6- iPr2C6H3) with MeLi in Et2O, followed by treatment with GeCl2 ·dioxane or SnCl2, afforded [ L1ECl] [ L1 = ArN=C(Me)C(Me)2NAr; E = Ge ( 1), Sn ( 2)]. Moreover, L2Li [ L2 = ArN=C(Me)C(=CH2)NAr] reacted with GeCl2 ·dioxane in Et2O to form [{C(=CH)NAr}{C(Me)=NAr}]2(GeCl)2 ( 3). The byproducts are [{C(CH2)NAr}{C(Me)=NAr}Ge]2 ( 4) and L2H ( 5). Furthermore, the reaction of L with LiN iPr2 in Et2O, followed by treatment with SnCl2, afforded [ L2SnCl] ( 6). Compounds 1- 4 and 6 have been characterized by NMR spectroscopy and X-ray crystallography. [ABSTRACT FROM AUTHOR]

ABSTRACT The versatility of a previously developed method for the synthesis of chiral carbene-based palladacycles is demonstrated through the synthesis of two new chiral pyridine-functionalized N-heterocyclic carbene palladacycles with different wingtip groups. The efficiency in their resolution with different counter anions and different chiral amino acid salt auxiliaries has been studied. The absolute stereochemistries of all the chiral compounds were confirmed by single crystal X-ray crystallography. An unexpected Pd-N bond cleavage that resulted in the racemization of the α-carbon center in these complexes has also been investigated. Chirality 25:149-159, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Secondary phosphirane complexes isomerize above 100 °C to give the corresponding terminal phosphinidene complexes, which can be trapped by alkenes and alkynes. This reaction is a rare instance of the isomerization of a PIII derivative into a PI derivative. It appears to mimic the reductive elimination of alkanes from transition-alkylmetal hydrides. [ABSTRACT FROM AUTHOR]

Secondary phosphirane complexes isomerize above 100 °C to give the corresponding terminal phosphinidene complexes, which can be trapped by alkenes and alkynes. This reaction is a rare instance of the isomerization of a PIII derivative into a PI derivative. It appears to mimic the reductive elimination of alkanes from transition-alkylmetal hydrides. [ABSTRACT FROM AUTHOR]

Time‐based prospective memory (TBPM) is the ability to remember to do a planned task at the right time. In social interactions, people are often motivated to do things for others, which reflects an important factor that influences prospective memory, namely prosocial motivation. According to the motivational cognitive model, prosocial motivation promotes TBPM by paying more attention or adopting more effective strategies. This study explored the effect of prosocial motivation on TBPM under different time‐monitoring conditions within the motivational cognitive model framework. One hundred and thirty‐one university students participated in this experiment that adopted a 2 (groups: control, prosocial motivation) × 2 (viewing time conditions: limited, unlimited) between‐subjects design. The results revealed that the prosocial motivation group had better TBPM performance than the control group under both limited and unlimited viewing time conditions. At the same time, compared with the control group, the prosocial motivation group consumed more internal attention and utilized more strategies under both viewing time conditions, and their external attention was more effective. In addition, the external attention of the prosocial motivation group was higher only when time‐monitoring was unlimited. The results of this study further extend knowledge of the motivational cognitive model and expand its scope of application, which has theoretical significance. [ABSTRACT FROM AUTHOR]

Solid‐state glass nanopipettes provide a promising confined space that offers several advantages such as controllable size, simple preparation, low cost, good mechanical stability, and good thermal stability. These advantages make them an ideal choice for various applications such as biosensors, DNA sequencing, and drug delivery. In this review, we first delve into the functionalized nanopipettes for sensing various analytes and the methods used to develop detection means with them. Next, we provide an in‐depth overview of the advanced functionalization methodologies of nanopipettes based on diversified chemical kinetics. After that, we present the latest state‐of‐the‐art achievements and potential applications in detecting a wide range of targets, including ions, molecules, biological macromolecules, and single cells. We examine the various challenges that arise when working with these targets, as well as the innovative solutions developed to overcome them. The final section offers an in‐depth overview of the current development status, newest trends, and application prospects of sensors. Overall, this review provides a comprehensive and detailed analysis of the current state‐of‐the‐art functionalized nanopipette perception sensing and development of detection means and offers valuable insights into the prospects for this exciting field. [ABSTRACT FROM AUTHOR]

A 1,2‐dihydrophosphination of bis(phenylphosphino)ethane with a wide range of activated olefins was achieved in a catalytic manner with enantiomeric and diastereomeric excess of up to >99% and 44% respectively. The protocol can be extended to selected substrates leading to free P‐ and C‐chiral 1,2‐diphosphines. The synthesized ligands can also undergo direct complexation onto palladium affording complexes with complete retention of stereo‐integrity. [ABSTRACT FROM AUTHOR]

The ruthenacyclic carbamoyl complexes [RuX{2‐NHC(O)C5H3NR}(CO)2(NCMe)] (R = H and Me; X = Br and SC6H3‐o,o‐Me2) are excellent catalysts for the hydrolysis of organosilanes, particularly towards primary silanes, generating hydrogen under ambient conditions within seconds. These complexes are structural mimics of the [Fe]‐hydrogenase active site and like the natural enzyme, a labile ligand at the sixth coordination site is essential to the catalytic activity. Complexes [RuX{2‐NHC(O)C5H3NR}(CO)2(NCMe)] (R = H and Me; X = Br and SC6H3‐o,o‐Me2) are excellent catalysts for the hydrolysis of organosilanes, particularly towards primary silanes, generating hydrogen under ambient conditions within seconds. These complexes are structural mimics of the [Fe]‐hydrogenase cofactor; a labile ligand at the sixth coordination site is essential to the catalytic activity. [ABSTRACT FROM AUTHOR]

Metal‐free activation of homoatomic E−E σ bonds (E=P, B) in white phosphorus (P4) and bis(catecholato)diboron (B2cat2) with a 1,2‐diboraallene 1 is reported. The 1:1 and 1:2 reactions of P4 with 1 afford BnP4 cages (2: n=2, 3: n=4), whereas a stoichiometric mixture of 1 and B2cat2 undergoes homonuclear catenation through the addition of the B−B σ bond of B2cat2 across the B=B double bond of 1 (i.e. diboration), which leads to the formation of a tetraborane (4) featuring a B4 chain. Metal‐free activation of homoatomic E−E σ bonds (E=P, B) in white phosphorus (P4) and bis(catecholato)diboron (B2cat2) with a 1,2‐diboraallene is reported. The former affords BnP4 cages (n=2, 4), whereas the latter leads to the formation of a tetraborane featuring a B4 chain through homonuclear catenation. [ABSTRACT FROM AUTHOR]

Metal‐free activation of homoatomic E−E σ bonds (E=P, B) in white phosphorus (P4) and bis(catecholato)diboron (B2cat2) with a 1,2‐diboraallene 1 is reported. The 1:1 and 1:2 reactions of P4 with 1 afford BnP4 cages (2: n=2, 3: n=4), whereas a stoichiometric mixture of 1 and B2cat2 undergoes homonuclear catenation through the addition of the B−B σ bond of B2cat2 across the B=B double bond of 1 (i.e. diboration), which leads to the formation of a tetraborane (4) featuring a B4 chain. [ABSTRACT FROM AUTHOR]

The cover picture shows the isolation of the first stable four‐coordinate silanechalcogenones comprising an acyclic amido substituent by a straightforward oxidation of the amidinato silicon(II) bis(trimethylsilyl)amide with chalcogens. In the background, the shadow of a lion represents Singapore, called “The Lion City”, whose name, incidentally, starts with the same two letters of the element symbol for silicon, and the three different colors of the “hair” of the lion represent the three chalcogens, S, Se, and Te. Details are discussed in the article by C.‐W. So et al. on p. 3821 ff. For more on the story behind the cover research, see the Cover Profile. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue is the group of Cheuk-Wai So at the Nanyang Technological University, Singapore. The cover image shows the isolation of the first stable four-coordinate silanechalcogenones comprising an acyclic amido substituent by a straightforward oxidation of the amidinato silicon(II) bis(trimethylsilyl)amide with chalcogens. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "Asymmetric Synthesis of P-Stereogenic Diarylphosphinites by Palladium-catalyzed Enantioselective Addition of Diarylphosphines to Benzoquinone" by Y. Huang and colleagues published in "Journal of the American Chemical Society" in 2014.

The reaction of the NHC-disilicon(0) complex [(IAr)Si=Si(IAr)] ( 1, IAr=:C{N(Ar)C(H)}2, Ar=2,6- iPr2C6H3) with two equiv of elemental Te in toluene at room temperature for three days afforded a mixture of the first dimeric NHC-silicon monotelluride [(IAr)Si=Te]2 ( 2) and its isomeric complex [(IAr)Si(μ-Te)Si(IAr)=Te] ( 3). When the same reaction was performed for ten days, only 3 was isolated from the reaction mixture. Compound 1 reacted with four equiv of elemental Te in toluene for four weeks, which proceeded through the formation of 2, 3 and the NHC-disilicon tritelluride complex [{(IAr)Si(=Te)}2Te] ( 5-Te), to form the dimeric NHC-silicon ditelluride [(IAr)Si(=Te)(μ-Te)]2 ( 4). The reactions are in line with theoretical mechanistic studies for the formation of 4. Compound 3 reacted with one equiv of elemental sulfur in toluene to form the first NHC-disilicon sulfur ditelluride complex [{(IAr)Si(=Te)}2S] ( 5-S). [ABSTRACT FROM AUTHOR]

The reaction of the NHC-disilicon(0) complex [(IAr)Si=Si(IAr)] ( 1, IAr=:C{N(Ar)C(H)}2, Ar=2,6- iPr2C6H3) with two equiv of elemental Te in toluene at room temperature for three days afforded a mixture of the first dimeric NHC-silicon monotelluride [(IAr)Si=Te]2 ( 2) and its isomeric complex [(IAr)Si(μ-Te)Si(IAr)=Te] ( 3). When the same reaction was performed for ten days, only 3 was isolated from the reaction mixture. Compound 1 reacted with four equiv of elemental Te in toluene for four weeks, which proceeded through the formation of 2, 3 and the NHC-disilicon tritelluride complex [{(IAr)Si(=Te)}2Te] ( 5-Te), to form the dimeric NHC-silicon ditelluride [(IAr)Si(=Te)(μ-Te)]2 ( 4). The reactions are in line with theoretical mechanistic studies for the formation of 4. Compound 3 reacted with one equiv of elemental sulfur in toluene to form the first NHC-disilicon sulfur ditelluride complex [{(IAr)Si(=Te)}2S] ( 5-S). [ABSTRACT FROM AUTHOR]

In real life, we are often motivated to plan things to be performed at specific times in the future. Some of these intended actions help other individuals, and thus involve time‐based prospective memory (TBPM) under prosocial motivational conditions. Children's social development is very rapid, and they have relatively stable prosocial motivation during school age. Few studies have paid attention to this issue. This study focuses on three aspects of this issue: (1) the impact of prosocial motivation on the TBPM of school‐age children, (2) whether there are sex differences in this effect, and, for the first time, (3) the processing mechanism by which prosocial motivation affects TBPM in school‐age children in the framework of the motivation cognitive model. A total of 112 elementary school students, aged between 8 and 12, participated in the experiment, using a 2 (group: prosocial motivation, control) × 2 (sex: boy, girl) between‐subjects design. The results showed that prosocial motivation can significantly reduce children's time difference of TBPM. However, we found no sex differences in the effect of prosocial motivation on TBPM in the above two indicators. With regard to the processing mechanism, we found that the prosocial motivation group paid more attention to external time information throughout the experiment. However, their internal attention and the effectiveness of attention did not improve. These results partially support the motivation cognitive model. Overall, this study found that prosocial motivation relies mainly on external attention to improve the TBPM performance of school‐age children. [ABSTRACT FROM AUTHOR]

Sulfur‐embedded polycyclic aromatic compounds have been used as building blocks for numerous organic semiconductors over the past few decades. While the success is based on thiophene‐containing compounds, aromatic compounds that contain thiepine, a sulfur‐containing seven‐membered‐ring arene, has been less well investigated. Here we report the synthesis and properties of π‐extended pyrrole‐fused heteropine compounds such as thiepine and oxepine. A π‐extended pyrrole‐fused thiepine exhibited a "pitched π‐stacking" structure in the crystal, and exhibited a high charge carrier mobility of up to 1.0 cm2 V−1 s−1 in single‐crystal field‐effect transistors. [ABSTRACT FROM AUTHOR]