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A highly sensitive fluorescence sensor for monitoring low concentrations of hydrogen peroxide was designed. The sensor employs the commercially available palladium or platinum metal on activated charcoal as catalysts to decompose hydrogen peroxide into water and molecular oxygen. The produced oxygen concentration can be measured in real time using an oxygen-sensitive layer doped with photostable oxygen probes. The sensor exhibits high sensitivity that is able to measure hydrogen peroxide concentration down to 20 ppb and can measure hydrogen peroxide concentration in the range of 0.1–100 ppm and 0.02–100 ppm, respectively. The response is fully reversible and the typical response time is less than one minute, which makes it suitable to continuously measure hydrogen peroxide over a long duration. Due to the excellent batch-to-batch consistency of palladium or platinum metal on activated charcoal, the sensor can be massively produced with good reproducibility and affordable price, which holds great potential for constructing sensors for industrial and practical applications. [ABSTRACT FROM AUTHOR]

Biocatalysis is an attractive approach for the synthesis of chiral pharmaceuticals and fine chemicals, but assessing and/or improving the enantioselectivity of biocatalyst towards target substrates is often time and resource intensive. Although machine learning has been used to reveal the underlying relationship between protein sequences and biocatalytic enantioselectivity, the establishment of substrate fitness space is usually disregarded by chemists and is still a challenge. Using 240 datasets collected in our previous works, we adopt chemistry and geometry descriptors and build random forest classification models for predicting the enantioselectivity of amidase towards new substrates. We further propose a heuristic strategy based on these models, by which the rational protein engineering can be efficiently performed to synthesize chiral compounds with higher ee values, and the optimized variant results in a 53-fold higher E-value comparing to the wild-type amidase. This data-driven methodology is expected to broaden the application of machine learning in biocatalysis research. Machine learning has been used to reveal the relationship between protein sequences and biocatalytic enantioselectivity, but the establishment of substrate fitness space is challenging. Herein, the authors build random forest classification models for predicting the enantioselectivity of amidase toward different substrates, adopting chemistry and geometry descriptors. [ABSTRACT FROM AUTHOR]

It has long been an aspirational goal to create artificial channel structures that replicate the feat achieved by ion channel proteins. Biological ion channels occasionally demonstrate multiple conductance states (known as subconductance), remaining a challenging property to achieve in artificial channel molecules. We report a funnel‐shaped single‐molecule channel constructed by an electron‐deficient macrocycle and two electron‐deficient aromatic imide arms. Planar lipid bilayer measurements reveal distinct current recordings, including a closed state, two conducting states, and spontaneous transitions between the three states, resembling the events seen in biological ion channels. The transitions result from conformational changes induced by chloride transport in the channel molecule. Both opening states show a non‐linear and rectifying I–V relationship, indicating voltage‐dependent transport due to the asymmetrical channel structure. This work could enhance our understanding of ion permeation and channel opening mechanism. [ABSTRACT FROM AUTHOR]

It has long been an aspirational goal to create artificial channel structures that replicate the feat achieved by ion channel proteins. Biological ion channels occasionally demonstrate multiple conductance states (known as subconductance), remaining a challenging property to achieve in artificial channel molecules. We report a funnel‐shaped single‐molecule channel constructed by an electron‐deficient macrocycle and two electron‐deficient aromatic imide arms. Planar lipid bilayer measurements reveal distinct current recordings, including a closed state, two conducting states, and spontaneous transitions between the three states, resembling the events seen in biological ion channels. The transitions result from conformational changes induced by chloride transport in the channel molecule. Both opening states show a non‐linear and rectifying I–V relationship, indicating voltage‐dependent transport due to the asymmetrical channel structure. This work could enhance our understanding of ion permeation and channel opening mechanism. [ABSTRACT FROM AUTHOR]

This study investigated chemical compositions and biocidal activities from the aerial parts of Rhododendron thymifolium against Tribolium castaneum, Lasioderma serricorne, and Ditylenchus destructor. In total, 13 components were isolated from the aerial parts of R. thymifolium by chromatographic separation techniques. Based on the results of MS, 1H NMR, and 13C NMR spectrometry, their structures were determined as ent-kaurane-16β-ol (1), pentacosane (2), undecanoic acid, ethyl ester (3), 1-Tridecanethiol (4), 1-Dodecanol (5), 4-Methyl-7-hydroxycoumarin (6), tertradecan-1-ol (7), apocynin (8), 3-Methoxy-4-methylbenzaldehyde (9), scopoletin (10), hyperin (11), quercetin (12), acetophenone (13). In addition, ent-kaurane-16β-ol (1) was isolated from R. thymifolium for the first time. Then, the insecticidal toxicities against T. castaneum, L. serricorne, and D. destructor. of compounds 1–13 were evaluated, and the results showed that apocynin (8) and acetophenone (13) exhibited obvious contact activity against the storage pests with LD50 values of 6.46 and 8.72 μg/adult respectively. Acetophenone (13) showed excellent contact activity against D. destructor with LC50 values of 0.08 mg/mL. The study clearly showed the active fractions from R. thymifolium have might potential to be developed into potential compounds on storage insect prevention. [ABSTRACT FROM AUTHOR]

Photoactive black‐phase formamidinium lead triiodide (α‐FAPbI3) perovskite has dominated the prevailing high‐performance perovskite solar cells (PSCs), normally for those spin‐coated, conventional n‐i‐p structured devices. Unfortunately, α‐FAPbI3 has not been made full use of its advantages in inverted p‐i‐n structured PSCs fabricated via blade‐coating techniques owing to uncontrollable crystallization kinetics and complicated phase evolution of FAPbI3 perovskites during film formation. Herein, a customized crystal surface energy regulation strategy has been innovatively developed by incorporating 0.5 mol % of N‐aminoethylpiperazine hydroiodide (NAPI) additive into α‐FAPbI3 crystal‐derived perovskite ink, which enabled the formation of highly‐oriented α‐FAPbI3 films. We deciphered the phase transformation mechanisms and crystallization kinetics of blade‐coated α‐FAPbI3 perovskite films via combining a series of in‐situ characterizations and theoretical calculations. Interestingly, the strong chemical interactions between the NAPI and inorganic Pb−I framework help to reduce the surface energy of (100) crystal plane by 42 %, retard the crystallization rate and lower the formation energy of α‐FAPbI3. Benefited from multifaceted advantages of promoted charge extraction and suppressed non‐radiative recombination, the resultant blade‐coated inverted PSCs based on (100)‐oriented α‐FAPbI3 perovskite films realized promising efficiencies up to 24.16 % (~26.5 % higher than that of the randomly‐oriented counterparts), accompanied by improved operational stability. This result represented one of the best performances reported to date for FAPbI3‐based inverted PSCs fabricated via scalable deposition methods. [ABSTRACT FROM AUTHOR]

Photoactive black‐phase formamidinium lead triiodide (α‐FAPbI3) perovskite has dominated the prevailing high‐performance perovskite solar cells (PSCs), normally for those spin‐coated, conventional n‐i‐p structured devices. Unfortunately, α‐FAPbI3 has not been made full use of its advantages in inverted p‐i‐n structured PSCs fabricated via blade‐coating techniques owing to uncontrollable crystallization kinetics and complicated phase evolution of FAPbI3 perovskites during film formation. Herein, a customized crystal surface energy regulation strategy has been innovatively developed by incorporating 0.5 mol % of N‐aminoethylpiperazine hydroiodide (NAPI) additive into α‐FAPbI3 crystal‐derived perovskite ink, which enabled the formation of highly‐oriented α‐FAPbI3 films. We deciphered the phase transformation mechanisms and crystallization kinetics of blade‐coated α‐FAPbI3 perovskite films via combining a series of in‐situ characterizations and theoretical calculations. Interestingly, the strong chemical interactions between the NAPI and inorganic Pb−I framework help to reduce the surface energy of (100) crystal plane by 42 %, retard the crystallization rate and lower the formation energy of α‐FAPbI3. Benefited from multifaceted advantages of promoted charge extraction and suppressed non‐radiative recombination, the resultant blade‐coated inverted PSCs based on (100)‐oriented α‐FAPbI3 perovskite films realized promising efficiencies up to 24.16 % (~26.5 % higher than that of the randomly‐oriented counterparts), accompanied by improved operational stability. This result represented one of the best performances reported to date for FAPbI3‐based inverted PSCs fabricated via scalable deposition methods. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinase 2 (CDK2) has been recognized as one of the crucial factors in cell cycle regulation and has been proposed as a potential target for cancer therapies, particularly for colorectal cancer (CRC). Due to the increased incidence rate of CRC and challenges associated with existing treatment options, there is a need for efficient and selective anti-cancer compounds. The current work aims to explore the ability of novel kaempferol derivatives as CDK2 inhibitors by performing conceptual pharmacophore modeling, molecular docking, and molecular dynamic analysis. Kaempferol and its derivatives were obtained from PubChem, and the optimized 3D structures of the compounds were generated using Maestro Ligprep. Subsequently, a pharmacophore model was developed to identify compounds with high fitness values, resulting in the selection of several kaempferol derivatives for further study. We evaluated the ADMET properties of these compounds to assess their therapeutic potential. Molecular docking was conducted using Maestro and BIOVIA Discovery Studio version 4.0 to predict the binding affinities of the compounds to CDK2. The top candidates were subjected to MM-GBSA analysis to predict their binding free energies. Molecular dynamics simulations using GROMACS were performed to assess the thermodynamic stability of the ligand-protein complexes. The results revealed several kaempferol derivatives with high predicted binding affinities to CDK2 and favorable ADMET properties. Specifically, compounds 5281642, 5318980, and 14427423 demonstrated binding free energies of-30.26, -38.66, and -34.2 kcal/mol, respectively. Molecular dynamics simulations indicated that these ligand-protein complexes remained stable throughout the simulation period, with RMSD values remaining below 2 Ä. In conclusion, the identified kaempferol derivatives show potential as CDK2 inhibitors based on computational predictions and demonstrate stability in molecular dynamics simulations, suggesting their future application in CRC treatment by targeting CDK2. These computational findings encourage further experimental validation and development of kaempferol derivatives as anti-cancer agents. [ABSTRACT FROM AUTHOR]

Breakout is the most destructive accident that interrupts the smooth production process of continuous casting, which needs to take effective and accurate measures to predict. In light of the "Y" form tear trace left at slab surface when sticking breakout happens, computer vision techniques are used in this paper to convert the one-dimensional temperature signal measured in time sequence by thermocouples into two-dimensional temperature rate thermography of mold copper plate, forecasting breakout by capturing the "Y" shape sticking region characteristic in thermography. In an effort to process big quantity of thermography data in a precise and stable way and differentiate between sticking breakout sample and normal condition sample, deep convolutional neural network model is constructed for recognizing between these two, and we develop a mold breakout prediction model based on identifying abnormal visual sticking region through CNN (convolutional neural network). The test result indicates that model is able to detect sticking breakout samples out of different temperature patterns and exclude normal condition samples at the same time. With achieving a 100 pct prediction accuracy for true sticking breakout, fine-grained classification model obtains a lower false positive rate compared to transfer learning model and a better generalization performance, offering a new train of thought into establishing data-driven abnormality detection methods during continuous casting process. [ABSTRACT FROM AUTHOR]

In this study, we developed a numerical model of a slab continuous casting mold coupled with multi-phase and multi-physical fields, known as MPF-Mold, and explored the effect of Fc-Mold on fluid flow, heat transfer, and solidification in the mold. Firstly, the simulation results were carefully verified from five perspectives. Next, the fast Fourier transform (FFT) is introduced to discuss the difference between MPF-Mold and the model considering only the fluid flow in the simulation results of level fluctuation. Typically, mold oscillation can be disregarded when analyzing the degree of level fluctuation through numerical simulation. However, neglecting multi-phase heat transfer and solidification may lead to overestimations of the severity of level fluctuation, especially in the region near the narrow meniscus. When coupling MPF-Mold with Fc-Mold, the upper backflow in the mold becomes stable, increasing symmetry and reducing level fluctuation severity and abnormalities. The shell uniformity index on the wide face meniscus and the lower part of the narrow face in the mold is significantly improved. This suggests that the upper and lower magnetic poles of Fc-Mold are beneficial to the shell uniform growth of the wide face meniscus and lower part of the narrow face, respectively. However, a new 'concave' appears in the shell near the corner of the mold, as a result of the horizontal vortex caused by deviations in the jet flow. Therefore, the magnetic field needs to be optimized to stabilize the flow field. MPF-Mold demonstrates advantages in achieving a reasonable match of steel grade, equipment, and process, and contributing to the digital transformation of continuous casting. [ABSTRACT FROM AUTHOR]

Diagnostic markers are desperately needed for the early detection of pancreatic ductal adenocarcinoma (PDA). We describe sets of markers expressed in temporal order in mouse models during pancreatitis, PDA initiation and progression. Cell type specificity and the differential expression of PDA markers were identified by screening single cell (sc) RNAseq from tumor samples of a mouse model for PDA (KIC) at early and late stages of PDA progression compared to that of a normal pancreas. Candidate genes were identified from three sources: (1) an unsupervised screening of the genes preferentially expressed in mouse PDA tumors; (2) signaling pathways that drive PDA, including the Ras pathway, calcium signaling, and known cancer genes, or genes encoding proteins that were identified by differential mass spectrometry (MS) of mouse tumors and conditioned media from human cancer cell lines; and (3) genes whose expression is associated with poor or better prognoses (PAAD, oncolnc.org). The developmental progression of PDA was detected in the temporal order of gene expression in the cancer cells of the KIC mice. The earliest diagnostic markers were expressed in epithelial cancer cells in early-stage, but not late-stage, PDA tumors. Other early markers were expressed in the epithelium of both early- and late-state PDA tumors. Markers that were expressed somewhat later were first elevated in the epithelial cancer cells of the late-stage tumors, then in both epithelial and mesenchymal cells, or only in mesenchymal cells. Stromal markers were differentially expressed in early- and/or late-stage PDA neoplasia in fibroblast and hematopoietic cells (lymphocytes and/or macrophages) or broadly expressed in cancer and many stromal cell types. Pancreatitis is a risk factor for PDA in humans. Mouse models of pancreatitis, including caerulein treatment and the acinar-specific homozygous deletion of differentiation transcription factors (dTFs), were screened for the early expression of all PDA markers identified in the KIC neoplasia. Prognostic markers associated with a more rapid decline were identified and showed differential and cell-type-specific expression in PDA, predominately in late-stage epithelial and/or mesenchymal cancer cells. Select markers were validated by immunohistochemistry in mouse and human samples of a normal pancreas and those with early- and late-stage PDA. In total, we present 2165 individual diagnostic and prognostic markers for disease progression to be tested in humans from pancreatitis to late-stage PDA. [ABSTRACT FROM AUTHOR]

Bi-based halide perovskites, with much lower toxicity than Pb-based perovskites, have triggered enormous interest in optoelectronic applications. However, most Bi-based perovskites have low-dimensional crystalline structures which may have potential negative effects on carrier transport. Herein, zero-dimensional (CHDA)BiI5·3H2O is transformed into two-dimensional double perovskite (CHDA)2CuBiI8·0.5H2O through Cu+ introduction engineering, which shows increased orbital overlap and improved electronic band structure dispersion compared with the former. Notably, a 104-fold enhancement in photoresponse on–off ratio is observed for the (CHDA)2CuBiI8·0.5H2O SC photodetector. This advancement not only enhances our understanding of the intricate relationship between crystal structure and charge transport behavior in Bi-based perovskites but also paves the way for highly efficient and environmentally friendly optoelectronic device development. [ABSTRACT FROM AUTHOR]

Incorporation of privileged catalytic scaffolds into a macrocyclic skeleton represents an attractive strategy to furnish supramolecular catalysis systems with enzyme‐mimetic cavity and multi‐site cooperation. Herein we reported the synthesis, structure, binding properties and catalytic application of a series of chiral bis‐phosphate macrocycles toward the challenging asymmetric electrophilic fluorination. With a large, integrated chiral cavity and two cooperative phosphate sites, these macrocycles exhibited good inclusion toward 1,4‐diazabicyclo[2.2.2]octane (DABCO) dicationic ammoniums through complementary ion‐pair and C−H⋅⋅⋅O interactions, as confirmed by crystallographic and solution binding studies. In fluorocyclization of tryptamines with Selectfluor reagent which has a similar DABCO‐based dicationic structure, only 2 mol% macrocycle catalyst afforded the desired pyrroloindoline products in moderate yields and up to 91 % ee. For comparison, the acyclic mono‐phosphate analogue gave obviously lower reactivity and enantioselectivity (<20 % ee), suggesting a remarkable macrocyclic effect. The high catalytic efficiency and superior stereocontrol were ascribed to the tight ion‐pair binding and cavity‐directed noncovalent interaction cooperation. [ABSTRACT FROM AUTHOR]

Silica nanoparticles (SiNPs) with a chemically modified surface typically have a complicated chemical composition, which can significantly differ from their intended design. In this study, we systematically studied the effects of two surface modification methods on active-targeting of intracellular organelles of SiNPs: (1) the widely used step-by-step approach, which involves modifying SiNPs in two steps, i.e., the outer surface of SiNPs was firstly modified with amino groups and then these amino groups were linked with targeting groups, and (2) a newly developed one-step approach in which the ligand–silane complex is initially synthesized, followed by chemically immobilizing the complex on the surface of SiNPs. In the one-step approach, the molar ratio of reactants was precisely tuned so that there are no reactive groups left on the outer surface of SiNPs. Two essential organelles, mitochondria and the nucleus, were selected to compare the targeting performances of SiNPs synthesized via these two approaches. By characterizing physicochemical properties, including structural properties, the number of amino groups, surface charge, polydispersity, and cell colocalization, we demonstrated that SiNPs synthesized via the one-step approach with no residual linkage groups on their surface showed significantly improved mitochondria- and nucleus-targeting performances. This precise control of surface properties allows for optimized biological behavior and active-targeting efficiency of SiNPs. We anticipate that such simple and efficient synthetic strategies will enable the synthesis of effective SiNPs for active-targeting organelles in various biological applications. [ABSTRACT FROM AUTHOR]

An arm modification strategy, by replacing relatively rigid, electron-deficient side arms with flexible ether chain arms and linking them onto a tetraoxacalix[2]arene[2]triazine skeleton, was utilized to design an artificial molecular hourglass. The planar bilayer experiments confirmed the unimolecular channel mechanism and suggested reversed ion selectivity from the previously reported anion selectivity to weak cation selectivity. [ABSTRACT FROM AUTHOR]

Properly coordinating the initial solidification and heat transfer behavior of the meniscus of the mold is crucial for stabilizing and improving the surface quality of continuous casting slabs. The study comprehensively considers the geometric, contact, and motion characteristics of the meniscus under mold periodic oscillation, and develops a three-dimensional numerical model that couples the heat transfer of molten steel, shell solidification, and multiphase flow. The transient periodic heat transfer behavior of the meniscus in the mold is simulated and analyzed. The investigation begins with analyzing the distribution and variation of heat flux, and then focuses on analyzing the effects of steel level height, upper backflow, and thickness of mold flux on the formation of local high heat flux regions, periodic severe fluctuations, and sharp changes in corner heat flux. The transient variation and signal characteristics of heat flux near the meniscus are analyzed through Fast Fourier Transform (FFT) and Power Spectral Density (PSD). The analysis reveals that the high steel level with circulation is the main factor contributing to the formation of a local high heat flux zone. The flow patterns of molten steel and the uneven distribution of solid slag film can result in discontinuities in the region of sharp fluctuations. The variation of transient heat flux is affected by the relative motion between the initial solidified shell and the copper plate in the meniscus. The low-frequency heat flux is closely related to the melt flow fluctuations and the shell solidification, while the high-frequency heat flux is introduced by the mold oscillation. The signal difference of the heat flux near the meniscus is determined by its solidification rate and height. The results are beneficial for monitor the formation of initial solidification shell defects of the meniscus. [ABSTRACT FROM AUTHOR]

The first coordination‐saturated buckyball with a C60 molecule totally encased in an icosidodecahedral Cu30 in a (μ30‐(η2)30)‐fashion, namely C60@Cu30@Cl36N12, has been successfully realized by a C60‐templated assembly. The 48 outmost coordinating atoms (36Cl+12N) comprise a new simple polyhedron that is described by a ccf topology. Charge transfer from (CuI, Cl) to C60 explains the expansion of the light absorption up to 700 nm, and accounts for an ultrafast photophysical process that underpins its high photothermal conversion efficiency. This work makes a giant step forward in exohedral metallofullerene (ExMF) chemistry. [ABSTRACT FROM AUTHOR]

The first coordination‐saturated buckyball with a C60 molecule totally encased in an icosidodecahedral Cu30 in a (μ30‐(η2)30)‐fashion, namely C60@Cu30@Cl36N12, has been successfully realized by a C60‐templated assembly. The 48 outmost coordinating atoms (36Cl+12N) comprise a new simple polyhedron that is described by a ccf topology. Charge transfer from (CuI, Cl) to C60 explains the expansion of the light absorption up to 700 nm, and accounts for an ultrafast photophysical process that underpins its high photothermal conversion efficiency. This work makes a giant step forward in exohedral metallofullerene (ExMF) chemistry. [ABSTRACT FROM AUTHOR]

Background: Intellectual disability (ID) is characterized by an IQ < 70, which implies below-average intellectual function and a lack of skills necessary for daily living. ID may occur due to multiple causes, such as metabolic, infectious, and chromosomal causes. ID affects approximately 1–3% of the population; however, the cause can be identified in only 25% of clinical patients. Methods: To find the cause of genetic ID in a family, we performed whole-exome sequencing and Sanger sequencing to confirm the presence of a SETBP1 variant and real-time quantitative polymerase chain reaction to detect SETBP1 expression in the proband and normal controls. Results: A novel variant, c.942_943insGT (p. Asp316TrpfsTer28), was found in SETBP1. Furthermore, we observed that SETBP1 expression in patients was only 20% that of normal controls (P < 0.05). Conclusion: A heterozygous variant in SETBP1 associated with ID was found. This report provides further evidence for its genetic basis and support for clinical genetic diagnosis. [ABSTRACT FROM AUTHOR]

The n→π* interactions describing attractive force between lone pairs (lps) of nucleophile and carbonyl or polarized unsaturated bonds have recently attracted growing attentions in various disciplines. So far, such non‐covalent driving force are mainly concentrated to intramolecular systems. Intermolecular n→π* interactions in principle could produce fascinated supramolecular systems or facilitate organic reactions, however, they remain largely underexplored due to the very weak energy of individual interaction. This review attempts to give an overview of the challenging intermolecular n→π* interactions, much efforts emphasize the supramolecular systems, catalytic processes and spectroscopic measurements. [ABSTRACT FROM AUTHOR]

Chalcogenide phase-change materials (PCMs) are widely applied in electronic and photonic applications, such as non-volatile memory and neuro-inspired computing. Doped Sb2Te alloys are now gaining increasing attention for on-chip photonic applications, due to their growth-driven crystallization features. However, it remains unknown whether Sb2Te also forms a metastable crystalline phase upon nanoseconds crystallization in devices, similar to the case of nucleation-driven Ge-Sb-Te alloys. Here, we carry out ab initio simulations to understand the changes in optical properties of amorphous Sb2Te upon crystallization and post annealing. During the continuous transformation process, changes in the dielectric function are highly wavelength-dependent from the visible-light range towards the telecommunication band. Our finite-difference time-domain simulations based on the ab initio input reveal key differences in device output for color display and photonic memory applications upon tellurium ordering. Our work serves as an example of how multiscale simulations of materials can guide practical photonic phase-change applications. [ABSTRACT FROM AUTHOR]

Colloidal silicon nanocrystals (SiNCs) have garnered significant interest in optoelectronics and biomedical applications. Direct arylation provides pathways to enhance the solution processability of particles and manipulate the photophysical and electronic properties of SiNCs. Unfortunately, existing methods employed to prepare aryl‐functionalized SiNCs are based on organometallic coupling or transition‐metal‐catalyzed strategies, which require metal‐based reagents for preactivation or the precursors and complicated post‐treatment processes for product purification. Herein, we demonstrate a metal‐free method that directly functionalizes SiNCs with aryl‐based ligands. We design a series of benzyne derivatives formed from the thermal cyclization of predesigned alkynes, allowing efficient arylation on hydride‐terminated silicon surfaces under mild conditions. These aryl‐functionalized SiNCs exhibit strong blue emissions with nanosecond‐scaled decay, suggesting the formation of a new radiative recombination channel on SiNC surfaces. [ABSTRACT FROM AUTHOR]

Colloidal silicon nanocrystals (SiNCs) have garnered significant interest in optoelectronics and biomedical applications. Direct arylation provides pathways to enhance the solution processability of particles and manipulate the photophysical and electronic properties of SiNCs. Unfortunately, existing methods employed to prepare aryl‐functionalized SiNCs are based on organometallic coupling or transition‐metal‐catalyzed strategies, which require metal‐based reagents for preactivation or the precursors and complicated post‐treatment processes for product purification. Herein, we demonstrate a metal‐free method that directly functionalizes SiNCs with aryl‐based ligands. We design a series of benzyne derivatives formed from the thermal cyclization of predesigned alkynes, allowing efficient arylation on hydride‐terminated silicon surfaces under mild conditions. These aryl‐functionalized SiNCs exhibit strong blue emissions with nanosecond‐scaled decay, suggesting the formation of a new radiative recombination channel on SiNC surfaces. [ABSTRACT FROM AUTHOR]

Inspired by the unique structure and function of the natural chloride channel (ClC) selectivity filter, we present herein the design of a ClC‐type single channel molecule. This channel displays high ion transport activity with half‐maximal effective concentration, EC50, of 0.10 μM, or 0.075 mol % (channel molecule to lipid ratio), as determined by fluorescent analysis using lucigenin‐encapsulated vesicles. Planar bilayer lipid membrane conductance measurements indicated an excellent Cl−/K+ selectivity with a permeability ratio PCl- ${{_{{\rm Cl}{^{- }}}}}$ /PK+ ${{_{{\rm K}{^{+}}}}}$ up to 12.31, which is comparable with the chloride selectivity of natural ClC proteins. Moreover, high anion/anion selectivity (PCl- ${{_{{\rm Cl}{^{- }}}}}$ /PBr- ${{_{{\rm Br}{^{- }}}}}$ =66.21) and pH‐dependent conductance and ion selectivity of the channel molecule were revealed. The ClC‐like transport behavior is contributed by the cooperation of hydrogen bonding and anion–π interactions in the central macrocyclic skeleton, and by the existence of pH‐responsive terminal phenylalanine residues. [ABSTRACT FROM AUTHOR]

Inspired by the unique structure and function of the natural chloride channel (ClC) selectivity filter, we present herein the design of a ClC‐type single channel molecule. This channel displays high ion transport activity with half‐maximal effective concentration, EC50, of 0.10 μM, or 0.075 mol % (channel molecule to lipid ratio), as determined by fluorescent analysis using lucigenin‐encapsulated vesicles. Planar bilayer lipid membrane conductance measurements indicated an excellent Cl−/K+ selectivity with a permeability ratio PCl- ${{_{{\rm Cl}{^{- }}}}}$ /PK+ ${{_{{\rm K}{^{+}}}}}$ up to 12.31, which is comparable with the chloride selectivity of natural ClC proteins. Moreover, high anion/anion selectivity (PCl- ${{_{{\rm Cl}{^{- }}}}}$ /PBr- ${{_{{\rm Br}{^{- }}}}}$ =66.21) and pH‐dependent conductance and ion selectivity of the channel molecule were revealed. The ClC‐like transport behavior is contributed by the cooperation of hydrogen bonding and anion–π interactions in the central macrocyclic skeleton, and by the existence of pH‐responsive terminal phenylalanine residues. [ABSTRACT FROM AUTHOR]

Towards unexplored intermolecular n→π* interactions, presented herein are the synthesis, structure, self‐assembly and function of a multicarbonyl‐containing macrocycle calix[2]arene[2]barbiturate 1. X‐ray single crystal diffraction reveals the presence of Cl⋅⋅⋅C=O interactions in CH2Cl2⊂1 host‐guest complex and multiple intermolecular C=O⋅⋅⋅C=O interactions between molecules 1 in crystalline state. The intermolecular C=O⋅⋅⋅C=O interactions as attractive driving force led to unprecedented self‐assembly of nanotube with diameter around 1.4 nm and inner surface engineered by aromatic rings. SEM and TEM images of the self‐assembly of 1 demonstrated temperature‐dependent morphologies which allows the observation of spheres at 25 °C and rods at 0 °C, respectively. XRD analysis indicated consistent hexagonal patterns in the self‐assembly and single crystal lattice, indicating the nanotubes driven by C=O⋅⋅⋅C=O interactions constitute the basic structural architectures of both aggregates. The nanoscopic tubes (pores) formed in the rodlike single crystal engendering the separation of moving dyes were preliminarily investigated by a single‐crystal chromatography and crystal‐packed column chromatography. [ABSTRACT FROM AUTHOR]

While metals can be readily processed and reshaped by cold rolling, most bulk inorganic semiconductors are brittle materials that tend to fracture when plastically deformed. Manufacturing thin sheets and foils of inorganic semiconductors is therefore a bottleneck problem, severely restricting their use in flexible electronic applications. It is recently reported that a few single‐crystalline 2D van der Waals (vdW) semiconductors, such as InSe, are deformable under compressive stress. Here it is demonstrated that intralayer fracture toughness can be tailored via compositional design to make inorganic semiconductors processable by cold rolling. Systematic ab initio calculations covering a range of van der Waals semiconductors homologous to InSe are reported, leading to material‐property maps that forecast trends in both the susceptibility to interlayer slip and the intralayer fracture toughness against cracking. GaSe is predicted, and experimentally confirmed, to be practically amenable to being rolled to large (three quarters) thickness reduction and length extension by a factor of three. The fracture toughness and cleavage energy are predicted to be 0.25 MPa m0.5 and 15 meV Å−2, respectively. The findings open a new realm of possibility for alloy selection and design toward processing‐friendly group‐III chalcogenides for practical applications. [ABSTRACT FROM AUTHOR]

Tin‐based perovskite solar cells (Sn‐PSCs) have emerged as promising environmentally viable photovoltaic technologies, but still suffer from severe non‐radiative recombination loss due to the presence of abundant deep‐level defects in the perovskite film and under‐optimized carrier dynamics throughout the device. Herein, we healed the structural imperfections of Sn perovskites in an "inside‐out" manner by incorporating a new class of biocompatible chelating agent with multidentate claws, namely, 2‐Guanidinoacetic acid (GAA), which passivated a variety of deep‐level Sn‐related and I‐related defects, cooperatively reinforced the passivation efficacy, released the lattice strain, improved the structural toughness, and promoted the carrier transport of Sn perovskites. Encouragingly, an efficiency of 13.7 % with a small voltage deficit of ≈0.47 V has been achieved for the GAA‐modified Sn‐PSCs. GAA modification also extended the lifespan of Sn‐PSCs over 1200 hours. [ABSTRACT FROM AUTHOR]

Tin‐based perovskite solar cells (Sn‐PSCs) have emerged as promising environmentally viable photovoltaic technologies, but still suffer from severe non‐radiative recombination loss due to the presence of abundant deep‐level defects in the perovskite film and under‐optimized carrier dynamics throughout the device. Herein, we healed the structural imperfections of Sn perovskites in an "inside‐out" manner by incorporating a new class of biocompatible chelating agent with multidentate claws, namely, 2‐Guanidinoacetic acid (GAA), which passivated a variety of deep‐level Sn‐related and I‐related defects, cooperatively reinforced the passivation efficacy, released the lattice strain, improved the structural toughness, and promoted the carrier transport of Sn perovskites. Encouragingly, an efficiency of 13.7 % with a small voltage deficit of ≈0.47 V has been achieved for the GAA‐modified Sn‐PSCs. GAA modification also extended the lifespan of Sn‐PSCs over 1200 hours. [ABSTRACT FROM AUTHOR]

In order to find and develop new botanical pesticides against storage pests, components of the essential oil (EO) from Zanthoxylum bungeanum were identified by GC-MS and their insecticidal activity against the stored product pests were studied. The EO was obtained by steam distillation. Results showed that EO was rich in limonene (23.67), linalool (21.76) and linalyl anthranilate (10.87). In contact assays, linalool exhibited strongest toxicity to red flour beetle adult (LD50 = 17.06 μg/adult) and larvae (LD50 = 16.42 μg/larvae), and linalool was the most active one against the Lasioderma serricorne (LD50 = 15.36 μg/larvae). Then limonene and linalool showed different levels of fumigant activities against the two insect species. Synergism effect existed in the proportion of contact assays against Tribolium castaneum adults, and additive was observed in the proportion of 7:1 against T. castaneum larvae. This work provides important information for the development and utilization of Z. bungeanum and suggests that the EO of Z. bungeanum has the potential to serve as bio-insecticides for controlling pest damage in stored products. [ABSTRACT FROM AUTHOR]

Determination of pH values has a vital influence in many chemical and biological processes. To accurately determine pH values, we fabricated a highly photostable ratiometric fluorescent pH−sensitive nanosensor by staining the core of mesoporous silica nanoparticle with a rhodol dye and chemically labelling its outer shell with a rhodamine derivative dye. The two dyes possess opposite pH−responding directions, which increases the band of the signal change. There is a nine−fold change in fluorescence intensity ratios when the solution pH changes from 3.0 and 9.0. Meanwhile, the nanosensors displayed yellowish emission in low pH value, orange emission in mid pH value, and reddish emission in high pH value, which can be readily inspected by bare eyes. Last but not least, excellent photostability and reversibility features make the nanosensors useful for the continuous measuring of pH with high accuracy. [ABSTRACT FROM AUTHOR]

Ge–Sb–Te (GST) alloys are an important family of phase‐change materials employed in non‐volatile memories and neuromorphic devices. Conventional memory cells based on GST rely on the switching between an amorphous state and a metastable, disordered rocksalt‐like phase. Recently, however, it has been proposed that a special type of defect in layer‐structured GST—the so called "swapped bilayer" defect—is responsible for a novel phase‐change mechanism observed in GST‐based superlattices. Thus, disorder appears to play an important role in both types of switching mechanisms. Here, the observation of a new in‐plane twinning defect in hexagonal GeSb2Te4 by direct atomic‐scale imaging experiments is reported, which serves as the key ingredient to account for the abundance of inverted stacking faults in hexagonal GST and superlattices. Ab initio simulations reveal a low energy cost for these extended defects, and indicate that such defects can affect the electrical properties by inducing electron localization. This work provides additional insight into the nature and effects of structural disorder in GST phase‐change materials. [ABSTRACT FROM AUTHOR]

Due to the large distance or weak electronic conjugation between adjacent Bi‐I octahedrons, the charge transport in the low‐dimensional bismuth‐based hybrid perovskites is impeded and thus hinders their future developments. In this work, A‐site cation engineering by monoamine BZA (benzylamine) and diamine 3‐AMP (3‐(aminomethyl)pyridine) has been demonstrated as an efficient strategy to regulate the corresponding activation energy of ionic migration and carrier transport capacity. Given the higher polarity of 3‐AMP than BZA, producing a more efficient dielectric screening effect, it gives rise to obtaining the small exciton binding energy (50 meV) and low defect states (3.53×109 cm−3). The reduced distance of adjacent Bi‐I octahedrons by the bilateral anchoring of the 3‐AMP2+ diamine cation enhances both electronic conjugation and charge transport performance. Therefore, the photodetector for (3‐AMP)BiI5 SC shows a 243‐fold increase in on/off ratio compared with the (BZA)3BiI6 SC. [ABSTRACT FROM AUTHOR]

Due to the large distance or weak electronic conjugation between adjacent Bi‐I octahedrons, the charge transport in the low‐dimensional bismuth‐based hybrid perovskites is impeded and thus hinders their future developments. In this work, A‐site cation engineering by monoamine BZA (benzylamine) and diamine 3‐AMP (3‐(aminomethyl)pyridine) has been demonstrated as an efficient strategy to regulate the corresponding activation energy of ionic migration and carrier transport capacity. Given the higher polarity of 3‐AMP than BZA, producing a more efficient dielectric screening effect, it gives rise to obtaining the small exciton binding energy (50 meV) and low defect states (3.53×109 cm−3). The reduced distance of adjacent Bi‐I octahedrons by the bilateral anchoring of the 3‐AMP2+ diamine cation enhances both electronic conjugation and charge transport performance. Therefore, the photodetector for (3‐AMP)BiI5 SC shows a 243‐fold increase in on/off ratio compared with the (BZA)3BiI6 SC. [ABSTRACT FROM AUTHOR]

Hydrocarbon source rocks, as a main geologic factor of petroliferous systems in a sedimentary basin, play a key role in the accumulation of oil and gas and the formation of hydrocarbon accumulations. This study, which focuses on difficulties in prediction of hydrocarbon source rocks in basins or sags with low exploration degree and insufficient hydrocarbon source rock indicators, taking the Wenchang Formation of northern Zhu I Depression, Pearl River Mouth Basin as an example, proposed a hypothesis of "finding lakes and hydrocarbon source rocks". Detailed steps include, first , determination of the lacustrine basin boundary according to analysis of seismic foreset facies, determination of the depositional area based on the compilation of strata residual thickness maps, determination of the lacustrine basin shape according to deciphering slope break belt system, determination of the fluctuation of paleo-water depth according to biogeochemical indicators of mature exploration areas, determination of the lacustrine basin scale based on analyses of tectonics intensity and accommodation space, which prove the existence of the lacustrine basin and identify the range of semi deep-deep lake; second , further analyses of tectonopalaeogeomorphology, paleo-provenance, palaeoclimate and paleo-water depth to reconstruct the geologic background of the original basin and semi-deep-deep lacustrine facies, to determine the distribution of semi-deep/deep lacustrine sediments in combination with studies of logging facies, core facies, seismic facies and sedimentary facies, and to rank the sags' potential of developing hydrocarbon source rocks from controlling factors of source-to-sink system development; third , on the basis of regional sedimentary facies analysis, through identification and assessment of seismic facies types of semi-deep/deep lacustrine basins in mature areas, establishing "hydrocarbon source rock facies" in mature areas to instruct the identification and depicting of hydrocarbon source rocks in semi-deep/deep lacustrine basins with low exploration degree; fourth , through systematical summary of hydrocarbon-rich geological factors and lower limit index of hydrocarbon formation of the sags already revealed by drilling wells (e.g., sag area, tectonic subsidence amount, accommodation space, provenance characteristic, mudstone thickness, water body environment, sedimentary facies types of hydrocarbon source rocks), in correlation with corresponding indexes of sags with low exploration degree, then the evaluation and sorting of high-quality source rocks in areas with sparsely distributed or no drilling wells can be conducted with multi-factors and multiple dimensions. It is concluded that LF22 sag, HZ10 sag and HZ8 sag are II-order hydrocarbon rich sags; whereas HZS, HZ11 and HZ24 are the III-order hydrocarbon-generating sags. [ABSTRACT FROM AUTHOR]

The evolutionarily conserved serine/threonine kinase mTORC1 is a central regulator of cell growth and proliferation. mTORC1 is activated on the lysosome surface. However, once mTORC1 is activated, it is unclear whether mTORC1 phosphorylates local lysosomal proteins to regulate specific aspects of lysosomal biology. Through cross-reference analyses of the lysosome proteome with the mTORC1-regulated phosphoproteome, we identify STK11IP as a lysosome-specific substrate of mTORC1. mTORC1 phosphorylates STK11IP at Ser404. Knockout of STK11IP leads to a robust increase of autophagy flux. Dephosphorylation of STK11IP at Ser404 represses the role of STK11IP as an autophagy inhibitor. Mechanistically, STK11IP binds to V-ATPase, and regulates the activity of V-ATPase. Knockout of STK11IP protects mice from fasting or Methionine/Choline-Deficient Diet (MCD)-induced fatty liver. Thus, our study demonstrates that STK11IP phosphorylation represents a mechanism for mTORC1 to regulate lysosomal acidification and autophagy, and points to STK11IP as a promising therapeutic target for the amelioration of diseases with aberrant autophagy signaling. mTORC1, central regulator of cell growth and autophagy suppressor, is activated on the lysosome surface, but its local role in lysosomal biology remains unclear. Here the authors show STK11IP is a substrate of mTORC1 that regulates lysosomal acidification through V-ATPase and represses autophagy. [ABSTRACT FROM AUTHOR]

Phase‐change material (PCM) devices are one of the most mature nonvolatile memories. However, their high power consumption remains a bottleneck problem limiting the data storage density. One may drastically reduce the programming power by patterning the PCM volume down to nanometer scale, but that route incurs a stiff penalty from the tremendous cost associated with the complex nanofabrication protocols required. Instead, here a materials solution to resolve this dilemma is offered. The authors work with memory cells of conventional dimensions, but design/exploit a PCM alloy that decomposes into a heterogeneous network of nanoscale crystalline domains intermixed with amorphous ones. The idea is to confine the subsequent phase‐change switching in the interface region of the crystalline nanodomain with its amorphous surrounding, forming/breaking "nano‐bridges" that link up the crystalline domains into a conductive path. This conductive‐bridge switching mechanism thus only involves nanometer‐scale volume in programming, despite of the large areas in contact with the electrodes. The pore‐like devices based on spontaneously phase‐separated Ge13Sb71O16 alloy enable a record‐low programming energy, down to a few tens of femtojoule. The new PCM/fabrication is fully compatible with the current 3D integration technology, adding no expenses or difficulty in processing. [ABSTRACT FROM AUTHOR]

In utilizing glycerol to produce 1,3‐propanediol by microbial fermentation, the problems of low utilization rate and poor production performance need to be addressed. Based on the analysis of a mathematical model for 1,3‐propanediol production from glycerol by Klebsiella pneumoniae, this study theoretically investigated the effects of the dilution rate and the initial glycerol concentration in a two‐stage fermentation process and the feasibility of applying the feedback control methods. First, the optimal operation conditions of initial glycerol concentration and dilution rate were obtained. Through the use of feedback control theory, a control strategy for dilution rate was designed and optimized to shorten the settling time (time required for fermentation to reach stability) from 60.92 to 36.68 h for the first reactor, and from 53.66 to 22.68 h for the second reactor. In addition, the yield of 1,3‐propanediol in both two reactors reached up to 0.5 g·g−1. The simulation results indicated that the feedback control strategy for dilution rate increased the product concentration, reduced the residual glycerol in the fermentation broth, and greatly improved the performance of the fermentation. A feeding strategy of automatic control for dilution rate has been established and will be applied as an effective guiding scheme in automatic continuous fermentations for production of 1,3‐propanediol. [ABSTRACT FROM AUTHOR]

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Clavulanic acid (CA) is usually used together with other β‐lactam antibiotics as combination drugs to inhibit bacterial β‐lactamases, which is mainly produced from the fermentation of microorganism such as Streptomyces clavuligerus. Recently, it is still a challenge for downstream processing of low concentration and unstable CA from fermentation broth with high solid content, high viscosity, and small cell size. In this study, an integrated process was developed for simultaneous solid–liquid separation and primary purification of CA from real fermentation broth of S. clavuligerus using salting‐out extraction system (SOES). First, different SOESs were investigated, and a suitable SOES composed of ethanol/phosphate was chosen and further optimized using the pretreated fermentation broth. Then, the optimal system composed of 20% ethanol/15% K2HPO4 and 10% KH2PO4 w/w was used to direct separation of CA from untreated fermentation broth. The result showed that the partition coefficient (K) and recovery yield (Y) of CA from untreated fermentation broth were 29.13 and 96.8%, respectively. Simultaneously, the removal rates of the cells and proteins were 99.8% and 63.3%, respectively. Compared with the traditional method of membrane filtration or liquid–liquid extraction system, this developed SOES showed the advantages of simple operation, shorter operation time, lower process cost and higher recovery yield of CA. These results demonstrated that the developed SOES could be used as an attractive alternative for the downstream processing of CA from real fermentation broth. [ABSTRACT FROM AUTHOR]