In Situ Growth of Wafer-Scale Patterned Graphene and Fabrication of Optoelectronic Artificial Synaptic Device Array Based on Graphene/n-AlGaN Heterojunction for Visual Learning.

The unique optical and electrical properties of graphene-based heterojunctions make them significant for artificial synaptic devices, promoting the advancement of biomimetic vision systems. However, mass production and integration of device arrays are necessary for visual imaging, which is still challenging due to the difficulty in direct growth of wafer-scale graphene patterns. Here, a novel strategy is proposed using photosensitive polymer as a solid carbon source for in situ growth of patterned graphene on diverse substrates. The growth mechanism during high-temperature annealing is elucidated, leading to wafer-scale graphene patterns with exceptional uniformity, ideal crystalline quality, and precise control over layer number by eliminating the release of volatile from oxygen-containing resin. The growth strategy enables the fabrication of two-inch optoelectronic artificial synaptic device array based on graphene/n-AlGaN heterojunction, which emulates key functionalities of biological synapses, including short-term plasticity, long-term plasticity, and spike-rate-dependent plasticity. Moreover, the mimicry of visual learning in the human brain is attributed to the regulation of excitatory and inhibitory post-synapse currents, following a learning rule that prioritizes initial recognition before memory formation. The duration of long-term memory reaches 10 min. The in situ growth strategy for patterned graphene represents the novelty for fabricating fundamental hardware of an artificial neuromorphic system.

Electrochemical Oxidation Enables Radical Dearomative Spiroannulation to 2H-Spiro[benzofuran-3,9'-fluoren]-2-one.

Developing pragmatic strategies for accessing functional benzofuran-2-ones from 3-([1,1'-biphenyl]-2-yl)benzofuran remains an enduring challenge. Herein, we have achieved a highly discriminating electrochemical oxidative dearomative spiroannulation of 3-([1,1'-biphenyl]-2-yl)benzofuran, culminating in the synthesis of 2H-spiro[benzofuran-3,9'-fluoren]-2-one derivatives. By harnessing the electrophilic intermediates of benzofuryl radical cations supported by DFT calculations, we attain exceptional regioselectivity while eliminating the need for stoichiometric oxidants. Mechanistic investigations reveal a sequence of events involving the benzofuran radical cation, encompassing the capture of H2O, nucleophilic arene attack, and subsequent deprotonation, ultimately yielding the final benzofuran-2-ones.

Dweck's Social-Cognitive Model of Achievement Motivation in Science.

Dweck's social-cognitive model has long been used as a basis for achievement motivation research. However, few studies have examined the comprehensive model with interactions between perceived ability and achievement goals, and even fewer studies have focused on this model in a science academic context. With a sample of undergraduates (n = 1,036), the relations among mindsets, science academic self-efficacy, achievement goals, and achievement-related outcomes in science were examined. Fixed mindset related to performance goals. Growth mindset related to mastery goals and the number of courses completed. There was a significant indirect effect of growth mindset on interest value via mastery goals. Contrary to Dweck's model, the relation of performance goals to outcomes did not vary as a function of science academic self-efficacy. The findings provide empirical evidence for a more nuanced understanding of Dweck's model. They provide practical insights for how to support undergraduate students who are pursuing science-related career.

Preparation and Anti-Lung Cancer Activity Analysis of Guaiacyl-Type Dehydrogenation Polymer.

In this paper, guaiacyl dehydrogenated lignin polymer (G-DHP) was synthesized using coniferin as a substrate in the presence of ß-glucosidase and laccase. Carbon-13 nuclear magnetic resonance (13C-NMR) determination revealed that the structure of G-DHP was relatively similar to that of ginkgo milled wood lignin (MWL), with both containing ß-O-4, ß-5, ß-1, ß-ß, and 5-5 substructures. G-DHP fractions with different molecular weights were obtained by classification with different polar solvents. The bioactivity assay indicated that the ether-soluble fraction (DC2) showed the strongest inhibition of A549 lung cancer cells, with an IC50 of 181.46 ± 28.01 µg/mL. The DC2 fraction was further purified using medium-pressure liquid chromatography. Anti-cancer analysis revealed that the D4 and D5 compounds from DC2 had better anti-tumor activity, with IC50 values of 61.54 ± 17.10 µg/mL and 28.61 ± 8.52 µg/mL, respectively. Heating electrospray ionization tandem mass spectrometry (HESI-MS) results showed that both the D4 and D5 were ß-5-linked dimers of coniferyl aldehyde, and the 13C-NMR and 1H-NMR analyses confirmed the structure of the D5. Together, these results indicate that the presence of an aldehyde group on the side chain of the phenylpropane unit of G-DHP enhances its anticancer activity.

Synthesis of Well-Ordered Mesoporous Aluminosilicates with High Aluminum Contents: The Challenge and the Promise.

SBA-15 has recently emerged as a potential material for the catalytic conversion of large molecules. Usually, SBA-15 has a low content of aluminum due to the conventional acidic synthesis medium. Although a few approaches have been adopted to prepare Al-SBA-15 with a high alumina content, it is still challenging to prepare well-ordered Al-SBA-15 with a high alumina content. Here, we demonstrate a facile synthesis process in neutral mediums for the grafting of Al into the framework of SBA-15. This approach relies mainly on the dissociation of Si-O-Si bonds and the polymerization of Si-O-Si/Al bonds promoted by sodium persulfate (SPS) in neutral mediums. In this way, well-ordered Al-SBA-15 with a high aluminum content and enhanced acidity was obtained. Results of X-ray fluorescence spectroscopy (XRF) showed an n(SiO2)/n(Al2O3) ratio of 13.7, much lower than that of the conventional sample (21.7) obtained in acidic medium. The characterization results indicated the presence of a well-ordered Al-containing mesophase with high hydrothermal stability. Notably, the Al content and the acidity of Al-SBA-15 can be tuned by changing the SPS amount.

Electrooxidative double C-H/C-H coupling of phenols with 3-phenylbenzothiophenes: facile access to benzothiophene derivatives.

An efficient electrooxidative double C-H/C-H coupling of phenols with 3-phenylbenzothiophene has been developed under external oxidant- and catalyst-free conditions. This strategy could enable the highly tunable access to benzothiophene derivatives and exhibited broad substrate generality under mild conditions. The reaction is likely to proceed via the cross-coupling of the p-methoxylphenol radical and the 3-phenylbenzothiophene radical cation.

Many-particle induced band renormalization processes in few- and mono-layer MoS2.

Band renormalization effects play a significant role for two-dimensional (2D) materials in designing a device structure and customizing their optoelectronic performance. However, the intrinsic physical mechanism about the influence of these effects cannot be revealed by general steady-state studies. Here, band renormalization effects in organic superacid treated monolayer MoS2, untreated monolayer MoS2and few-layer MoS2are quantitatively analyzed by using broadband femtosecond transient absorption spectroscopy. In comparison with the untreated monolayer, organic superacid treated monolayer MoS2maintains a direct bandgap structure with two thirds of carriers populated at K valley, even when the initial exciton density is as high as 2.05 × 1014cm-2(under 400 nm excitations). While for untreated monolayer and few-layer MoS2, many-particle induced band renormalizations lead to a stronger imbalance for the carrier population between K and Q valleys inkspace, and the former experiences a direct-to-indirect bandgap transition when the initial exciton density exceeds 5.0 × 1013cm-2(under 400 nm excitations). Those many-particle induced band renormalization processes further suggest a band-structure-controlling method in practical 2D devices.

Trion dynamics and charge photogeneration in MoS2 nanosheets prepared by liquid phase exfoliation.

Since excitonic quasiparticles, including excitons, trions and charges, have a great influence on the photoelectric characteristics of two-dimensional (2D) transition metal dichalcogenides (TMDs), systematic explorations of the trion dynamics and charge photogeneration in 2D TMDs are important for their future optoelectronic applications. Here, broadband femtosecond transient absorption spectroscopic experiments are performed first to investigate the peak shifting and broadening kinetics in MoS2 nanosheets in solution prepared by liquid phase exfoliation (LPE-MoS2, ∼9 layers, 9L), which reveal that the binding energies for the A-, B-, and C-exciton states are ∼77 meV, ∼76 meV, and -70 meV (the energy difference between free charges and excitons; the negative sign for C-excitons means a spontaneous dissociation nature in band-nesting regions), respectively. Then, the trion dynamics and charge photogeneration in LPE-MoS2 nanosheets have been studied in detail, demonstrating that they are comparable to those in chemical vapor deposition grown MoS2 films (1L-, 3L- and 7L-MoS2). These experimental results suggest that LPE-TMD nanosheets also have the potential for use in charge-related optoelectronic devices based on 2D TMDs.

Elemental-Sulfur-Incorporated Cyclizations of Pyrrolidines Leading to Thienopyrroles.

We report, herein, the synthesis of thieno[3,2-b]pyrroles from the direct oxidative [4 + 1] cyclization of 2-alkynyl pyrrolidines with elemental sulfur. This transformation likely originates from electrophilic attack at the ß-position of pyrrolidine followed by an intramolecular thienannulation to deliver the desired product. Mechanistic investigation suggests that the present reaction involves the formation of dihydrothieno[3,2-b]pyrrole as an intermediate.

Lattice -Mismatch-Induced Ultrastable 1T-Phase MoS2-Pd/Au for Plasmon-Enhanced Hydrogen Evolution.

Metallic 1T-phase transition metal dichalcogenides (TMDs) are of considerable interest in enhancing catalytic applications due to their abundant active sites and good conductivity. However, the unstable nature of 1T-phase TMDs greatly impedes their practical applications. Herein, we developed a new approach for the synthesis of highly stable 1T-phase Au/Pd-MoS2 nanosheets (NSs) through a metal assembly induced ultrastable phase transition for achieving a very high electrocatalytic activity in the hydrogen evolution reaction. The phase transition was evoked by a novel mechanism of lattice-mismatch-induced strain based on density functional theory (DFT) calculations. Raman spectroscopy and transmission electron microscopy (TEM) were used to confirm the phase transition on experimental grounds. A novel heterostructured 1T MoS2-Au/Pd catalyst was designed and synthesized using this mechanism, and the catalyst exhibited a 0 mV onset potential in the hydrogen evolution reaction under light illumination. Therefore, this method can potentially be used to fabricate 1T-phase TMDs with remarkably enhanced activities for different applications.

Metal-Free Dehydrogenative Double C-H Sulfuration To Access Thieno[2,3-b]indoles Using Elemental Sulfur.

We report a base-promoted metal-free approach for the synthesis of thieno[2,3-b]indole derivatives. This method combined four C-H σ-bond cleavage reactions of two different kinds of C-H bonds and two C-S σ-bond formation processes. A series of thieno[2,3-b]indoles were obtained starting from 3-benzylindole derivatives with good yields and high regioselectivity, with the elemental sulfur serving as a cheap and readily available sulfur source. Good efficiency could be maintained even when the reaction was performed on a gram scale. A plausible mechanism was proposed on the basis of mechanistic studies.

Tailored Design of Differently Modified Mesoporous Materials To Deeply Understand the Adsorption Mechanism for Polycyclic Aromatic Hydrocarbons.

A series of SBA-15 with different modifications have been successfully prepared and applied as adsorbents to remove polycyclic aromatic hydrocarbons (PAHs) from aqueous solutions. The morphology and structural properties of the chemically modified materials are all similar to those of pure SBA-15, and thus the difference of PAHs adsorption capacity can be directly attributed to the different functional groups, which is favorable to deeply explore the adsorption mechanism. Adsorption kinetics and isotherm experiments for naphthalene (Nap), anthracene (Ant), and pyrene (Pyr) were carried out, and the results reveal that the adsorption processes follow a pseudo-second-order rate equation and the equilibrium can be achieved within 120 min for Nap and Ant, whereas only 90 min for Pyr, indicating that the more hydrophobic molecules, the easier and faster adsorption can be obtained. All of the adsorption isotherms fit well with the Freundlich model, suggesting the unevenly distributed active sites on adsorbents. The phenyl-functionalized materials possess the highest adsorption capacity, implying that the π-π interaction is the most primary interaction and plays the predominant role in the studied PAHs adsorption, superior to the acidic and hydrophobic interaction. Our research sheds light on the design and synthesis of advanced and highly efficient adsorbents to remove PAHs from aqueous solutions.

Investigation of the interaction of aurantio-obtusin with human serum albumin by spectroscopic and molecular docking methods.

The interaction between human serum albumin (HSA) and aurantio-obtusin was investigated by spectroscopic techniques combined with molecular docking. The Stern-Volmer quenching constants (KSV ) decreased from 8.56 × 105  M-1 to 5.13 × 105  M-1 with a rise in temperatures from 289 to 310 K, indicating that aurantio-obtusin produced a static quenching of the intrinsic fluorescence of HSA. Time-resolved fluorescence studies proved again that the static quenching mechanism was involved in the interaction. The sign and magnitude of the enthalpy change as well as the entropy change suggested involvement of hydrogen bonding and hydrophobic interaction in aurantio-obtusin-HSA complex formation. Aurantio-obtusin binding to HSA produced significant alterations in secondary structures of HSA, as revealed from the time-resolved fluorescence, Fourier transform infrared (FT-IR) spectroscopy, three-dimensional (3D) fluorescence and circular dichroism (CD) spectral results. Molecular docking study and site marker competitive experiment confirmed aurantio-obtusin bound to HSA at site I (subdomain IIA).

Link between community-acquired pneumonia and vitamin D levels in older patients.

PURPOSE: To investigate the correlation between the level of 25-hydroxyvitamin D [25-(OH)D] and community-acquired pneumonia (CAP) in elderly patients. METHODS: A total of 163 older patients were chosen from those hospitalized between October 2011 and October 2012. Patients were divided into pneumonia and non-pneumonia groups, and the concentrations of 25-(OH)D (nmol/L) in serum were measured. Clinical data were then compared between the two groups and pneumonia-related risk factors were analyzed using logistic regression. RESULTS: Among the 163 older hospitalized patients, 49 suffered from pneumonia. Levels of 25-(OH)D, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) were lower (P < 0.05) in the pneumonia group, while severe vitamin D (VitD) deficiency was higher in the pneumonia group (71.4 vs. 19.3%; P < 0.0001). Age and number of hospitalization days were higher in the pneumonia group (P < 0.05). Multivariate logistic regression showed that age and VitD levels were independent risk factors for pneumonia. No significant difference was observed in terms of gender, onset season, body mass index, or smoking and drinking history between the two groups (P > 0.05). CONCLUSION: The older patients with CAP had a severe VitD deficiency, indicating that low levels of VitD might play an important role in the occurrence and development of CAP.

Constructing Post-Permeation Method to Fabricate Polymer/Nanocrystals Hybrid Solar Cells with PCE Exceeding 6.

A post-permeation method is constructed for fabricating bulk-heterojunction hybrid solar cells. Porous CdTe film is prepared by annealing the mixture solution of aqueous CdTe nanocrystals and cetyltrimethyl ammonium bromide, after which the post-permeation of polymer is employed. By this method, kinds of polymers can be applied regardless of the intermiscibility with the nanoparticles. The inorganic nanocrystals and the polymer can be treated under respective optimized annealing temperatures, which can facilitate the growth of nanocrystals without damaging the polymers. A high power conversion efficiency of 6.36% in the polymer/nanocrystals hybrid solar cells is obtained via systematical optimization.

Photoluminescence quenching of inorganic cesium lead halides perovskite quantum dots (CsPbX3) by electron/hole acceptor.

Recently, all-inorganic cesium lead halide perovskites (CsPbX3) quantum dots (QDs) have attracted great attention due to their halogen composition and size tunable band gap engineering, the same physical mechanism that is responsible for excellent performance in light-emitting devices. However, little is known about the time-resolved fluorescence quenching dynamics process of these CsPbX3 QDs. In this article, we present comprehensive contrastive spectral studies on the electron and hole extraction dynamics of CsPbX3 colloidal QDs with and without quencher by time-resolved femtosecond transient absorption (TA) and time-correlated single-photon counting (TCSPC) spectroscopy methods. We have identified that the partial electrons of the conduction band and holes of the valence band of CsPbX3 QDs can be directly extracted by tetracyanoethylene (TCNE) and phenothiazine (PTZ), respectively. Moreover, compared with the CsPbBr3 QDs, the CsPbI3 QDs showed relatively slower charge extraction rates. We also found that the CsPbBr3 QDs with smaller size showed faster carrier recombination rates and photoluminescence (PL) decay lifetime due to the relatively stronger quantum confinement effects. We believe that this study may be useful for realising optimal applications in photovoltaic and light emission devices.

[Self-assembling peptide GFS-4 nanofiber scaffolds for three-dimensional cell cultures and myocardial infarction repair].

The purpose of this study is to investigate the effects of self-assembling peptide GFS-4 on three-dimen-sional myocardial cell culture and tissue repair of myocardial infarction. The circular dichroism (CD) spectrum was used to detect secondary structure of GFS-4, and atomic force microscope (AFM) was used to analyze the microstructure of self-assembly. The nanofiber scaffolds self-assembled by GFS-4 were used as the three-dimensional culture material to observe the growth effect of cardiomyocytes. The model of myocardial infarction was established and the effect of GFS-4 on myocardial infarction was studied. The results indicated that self-assembling peptide GFS-4 could form mainly ß-sheet structure that can form dense nanofiber scaffolds after 24 hours' self-assembling. The myocardial cells had a favorable growth status in GFS-4 nanofiber scaffold hydrogel when cells treated in three-dimen-sional cell culture. The experiment of repairing myocardial infarction in vitro proved that peptide GFS-4 hydrogel scaffold could alleviate tissue necrosis in a myocardial infarction area. As a new nanofiber scaffold material, self-assembling peptide GFS-4 can be used for three-dimensional cell culture and tissue repairing in myocardial infarction area.

Interaction of human serum albumin with novel imidazole derivatives studied by spectroscopy and molecular docking.

This study was a detailed characterization of the interaction of a series of imidazole derivatives with a model transport protein, human serum albumin (HSA). Fluorescence and time-resolved fluorescence results showed the existence of a static quenching mode for the HSA-imidazole derivative interaction. The binding constant at 296 K was in the order of 10(4) M(-1), showing high affinity between the imidazole derivatives and HSA. A site marker competition study combined with molecular docking revealed that the imidazole derivatives bound to subdomain IIA of HSA (Sudlow's site I). Furthermore, the results of synchronous, 3D, Fourier transform infrared, circular dichroism and UV-vis spectroscopy demonstrated that the secondary structure of HSA was altered in the presence of the imidazole derivatives. The specific binding distance, r, between the donor and acceptor was obtained according to fluorescence resonance energy transfer.

Executive compensation and corporate sustainability: Evidence from ESG ratings.

Selecting A-share listed companies in Shanghai and Shenzhen, China, during the period of 2012-2021 as research subjects, this study examines the relationship and operational mechanisms between executive compensation and corporate ESG Ratings. It is found that executive compensation incentives can significantly enhance corporate ESG Ratings. This effect is achieved through promoting green innovation efficiency, enhancing environmental information disclosure, and improving financial performance. However, this positive impact weakens with an increase in management shareholding, but strengthens with a higher proportion of independent directors. When compensation exceeds appropriate levels, overcompensation leads to a decline in ESG Ratings. The significance of this study lies in revealing potential pathways for enhancing corporate sustainability through executive compensation incentives, while also emphasizing the importance of formulating appropriate compensation strategies.

CRISPR-powered microfluidic biosensor for preamplification-free detection of ochratoxin A.

The CRISPR technology, which does not require complex instruments, expensive reagents or professional operators, has attracted a lot of attention. When utilizing the CRISPR-Cas system for detection, the pre-amplification step is often necessary to enhance sensitivity. However, this approach tends to introduce complexity and prolong the time required. To address this issue, we employed Pd@PCN-222 nanozyme to label single-stranded DNA, referred to as Pd@PCN-222 CRISPR nanozyme, which serves as the reporter of the CRISPR system. Pd@PCN-222 nanozyme possess exceptional catalytic activity for the reduction of H2O2. Compared with traditional electrochemical probe ferrocene and methylene blue without catalytic activity, there is a significant amplification of the electrochemical signal. So the need for pre-amplification was eliminated. In this study, we constructed a CRISPR-Cas system for ochratoxin A, utilizing the Pd@PCN-222 CRISPR nanozyme to amplified signal avoiding pre-amplification with outstanding detection of 1.21 pg/mL. Furthermore, we developed a microfluidic electrochemical chip for the on-site detection of ochratoxin A. This achievement holds significant promise in establishing a practical on-site detection platform for identifying food safety hazards.