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Monolayer and few-layer CoPS3 have been successfully synthesized via an Au-assisted exfoliation technique, with their transport properties subsequently investigated by conductive atomic force microscopy. Rectification effects can be observed in CoPS3 nanosheets due to the Schottky junction formation at the Au/CoPS3 interface, especially in configurations comprising two or more layer flakes. The distinct transport properties between monolayer and few-layer samples demonstrate that the charge transport behavior in the vertical direction is associated with the van der Waals gap. The calculated electron affinity for CoPS3 is about 4.84 eV, as revealed by the thermionic emission model. The results obtained contribute to the knowledge base concerning the transport characteristics of ultrathin MPX3, facilitating further exploration of the transport behavior of these materials and their potential applications in novel electronic devices. [ABSTRACT FROM AUTHOR]

Short single‐wall carbon nanotubes (SWCNTs)/epoxy composites were fabricated by a procedure of cutting and functionalizing SWCNTs, dispersion and curing, with a very low weight ratio of SWCNTs from 0.03% to 0.5%. It was found that the tensile fracture strength of composites increases with increasing SWCNT content initially, then reaches a maximum at 0.05 wt% and finally decreases with further increasing the SWCNT content. The fracture strength of the composite with 0.05 wt% SWCNTs (78.46 MPa) is ~160% of that of pure epoxy sample (48.64 MPa). A model analysis based on the competition of local matrix fracture and the debonding of short SWCNT was proposed. It revealed that there is a transition from local matrix fracture to the debonding of SWCNT when the SWCNT content increases, this transition leads to the decrease in the tensile strength. Further analyses indicated that the content of carbon nanotubes (CNTs) at the transition depends on their radius and length. Considering the effect of surface cracks on the fracture strength of pure epoxy sample, the theoretical analyses are qualitatively in agreement with the experimental results. The present study partly explains why the fracture strength of CNT reinforced composites has various results for a similar CNT loading in previous works. [ABSTRACT FROM AUTHOR]

To fully understand the mechanisms for shifting of coercive field (${E}_{\text {c}}$) during the bipolar stress cycling in doped HfO2 ferroelectric (FE) material, we present a systematic study with both characterization and simulation on HfZrOx (HZO) capacitor. First, with the help of time-dependent dielectric breakdown (TDDB) results, defect redistribution is found to be localized during the bipolar stress cycling. Then, with the advanced simulation framework Ginestra®, influences of work function (WF) mismatch of the electrodes and defect distribution on the ${E}_{\text {c}}$ symmetry and breakdown property are discussed. It indicates that the shift of ${E}_{\text {c}}$ is mostly due to the redistribution of defects from FE phase to non-FE phase and grain boundaries. Furthermore, nucleation limited switching (NLS) model is adopted to investigate the switching dynamics during coercive field shift in more detail. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the mechanism of Bletilla striata oligosaccharides (BO) in the treatment of ulcerative colitis (UC). A UC mouse model was induced by 3% Dextran sodium sulfate (DSS), and BO (200 mg/kg/d) were administered for intervention. The results show that BO effectively inhibited the release of intestinal inflammatory cytokines such as IL-6, TNF-α, and IL-1β. Also, BO profoundly elevated the secretion of mucins and the expression of tight junction (TJ) proteins to attenuate dysfunction of the intestinal barrier. The 16S rDNA sequencing and liquid chromatography/gas chromatography-mass spectrometer (LC/GC-MS) analysis of mouse feces revealed that BO regulated the disturbance of gut microbiota and intestinal metabolites. By using the in vitro fermentation broth of BO and gut microbiota-depleted mice treated with antibiotics, we confirmed the protection of BO against UC. In conclusion, BO played a role in improving UC by modulating gut microbial composition and intestinal metabolites, which provided new therapeutic strategies for UC treatment. [ABSTRACT FROM AUTHOR]

SUMMARY Pustule formation is pivotal for the development of the Xanthomonas citri subsp. citri (Xcc)‐induced citrus canker disease (CCD). Although our previous study demonstrated that the exogenous application of abscisic acid (ABA) facilitated pustule formation induced by Xcc, the precise mechanism remains elusive. The 9‐cis‐epoxycarotenoid dioxygenase (NCED) is a crucial enzyme in ABA biosynthesis. This study explored the role of citrus CsNCED1‐1 in CCD resistance through overexpression and RNA interference of CsNCED1‐1 in Wanjincheng orange (Citrus sinensis). Our findings indicated that CsNCED1‐1 negatively modulated CCD resistance by fostering ABA accumulation, concomitant with an increase in jasmonic acid (JA) and a decrease in salicylic acid (SA). Plants overexpressing CsNCED1‐1 displayed shortened leaves with smaller and denser stomata along with irregular and increased palisade cells. CsLOB1 is a known susceptibility gene for CCD, and CsbZIP40 positively influences resistance to this disease. We further confirmed that CsLOB1 promoted and CsbZIP40 suppressed the transcription of CsNCED1‐1 by directly binding to the CsNCED1‐1 promoter. Notably, CsbZIP40 and CsLOB1 showed a competitive relationship in the regulation of CsNCED1‐1 expression, with CsbZIP40 exhibiting greater competitiveness. Overall, our findings highlight that CsNCED1‐1 promotes susceptibility to citrus canker by disrupting JA‐ and SA‐mediated defense mechanisms and triggering the proliferation and remodeling of palisade cells, thereby facilitating pathogen colonization and pustule formation. This study offers novel insights into the regulatory mechanisms underlying citrus canker resistance and the role of CsNCED1‐1 in citrus. [ABSTRACT FROM AUTHOR]

The synthesis of carbyne has remained an elusive goal for decades. One of the significant reasons is that high-purity and high-concentration hydrogen end-capped polyynes (C 2n H 2) as the most important model molecule and precursors for carbyne have been not widely prepared. Herein, we develop a facile and universal strategy to obtain high-purity and high-concentration C 8 - 18 H 2 molecules using solid linear carbon chains with silver atom ending-capped (Ag 2 C 8-18) as reaction precursors. The purified and concentrated C 8 - 18 H 2 solution and Ag 2 C 8-18 powder are evaluated by a combination of X-ray photoelectron spectroscopy, nuclear magnetic resonance spectroscopy, Raman spectroscopy, UV–vis–NIR spectroscopy and transmission electron microscope. These results confirm that the high-purity and high-concentration C 2n H 2 are obtained through the reaction of metal carbides solid and hydrogen chloride molecule. Our strategy for investigating unprotected linear carbon chains in solid and the successful preparation of high-concentration C 2n H 2 from solid carbides provide a new avenue for the research of linear carbon chains. [Display omitted] [ABSTRACT FROM AUTHOR]

Fundamental understanding of constructing elevated catalysts to realize fast electron transfer and rapid mass transport in oxygen reduction reaction (ORR) chemistry by interface regulation and structure design is important but still ambiguous. Herein, a novel jellyfish‐like Mott–Schottky‐type electrocatalyst is developed to realize fast electron transfer and decipher the structure–mass transport connection during ORR process. Both spectroscopy techniques and density functional theory calculation demonstrate electrons spontaneously transfer from Fe to N‐doped graphited carbon at the heterojunction interface, thus accelerating electron transfer from electrode to reactant. Dynamic analysis indicates unique structure can significantly improve mass transport of oxygen‐species due to two factors: one is electrolyte streaming effect caused by tentacle‐like carbon nanotubes; the other is effective collision probability in the semi‐closed cavity. Therefore, this Mott–Schottky‐type catalyst delievers superior ORR performance with high onset potential, positive half wave potential, and large current density. It also exhibits low overpotential when serving as an air cathode in Zn–air batteries. This work deepens understanding of the two key factors—electron transfer and mass transport—on determining the kinetic reaction of ORR process and offers a new avenue in constructing efficient Mott–Schottky electrocatalysts. [ABSTRACT FROM AUTHOR]

To simulate biological visual systems and surpass their functions and performance, it is essential to develop high‐performance optoelectronic neuromorphic electronics with broadband response, low power consumption, and fast response speed. Among these, optoelectronic synaptic transistors have emerged as promising candidates for constructing neuromorphic visual systems. In this work, flexible printed broadband (from 275 to 1050 nm) optoelectronic carbon nanotube synaptic transistors with good stability, high response speed (3.14 ms), and low‐power consumption (as low as 0.1 fJ per event with the 1050 nm pulse illumination) using PbS quantum dots (QDs) modified semiconducting single‐walled carbon nanotubes (sc‐SWCNTs) as active layers are developed. In response to optical pulses within the ultraviolet to near‐infrared wavelength range, the optoelectronic neuromorphic devices exhibit excitatory postsynaptic current, paired‐pulse facilitation, and a transition from short‐term plasticity to long‐term plasticity, and other optical synaptic behaviors. Furthermore, a simplified neural morphology visual array is developed to simulate integrated functions such as image perception, memory, and preprocessing. More importantly, it can also emulate other complicated bionic functions, such as the infrared perception of salmon eyes and the warning behavior of reindeer in different environments. This work holds immense significance in advancing the development of artificial neural visual systems. [ABSTRACT FROM AUTHOR]

Transition metal vanadates have gained significant attention as high performance anode materials for lithium ion batteries (LIBs). Herein, we successfully fabricated a novel hierarchical hybrid nanostructure of ordered mesoporous carbon (CMK-3) supported Ni3V2O8 composites (Ni3V2O8@CMK-3) through a facile hydrothermal method and a post-calcination process for the first time. Within such a hierarchical hybrid structure, short intercrossed Ni3V2O8 nanorods are firmly anchored onto the external surface of CMK-3 and ultrafine Ni3V2O8 nanoparticles are embedded in the internal channels of CMK-3. Benefitting from their robust porous structure and excellent conductive characteristic, the as-prepared hierarchical hybrid Ni3V2O8@CMK-3 composites exhibit long-term cycle stability with a high reversible capacity of 945.9 mA h g−1 after 200 cycles at a current density of 500 mA g−1 and superior high-rate capability (161.5 mA h g−1 when cycled at 20 A g−1) when used as a promising anode for LIBs. [ABSTRACT FROM AUTHOR]

Abstract: Organic–inorganic lead halide perovskites have shown great future for application in solar cells owing to their exceptional optical and electronic properties. To achieve high‐performance perovskite solar cells, a perovskite light absorbing layer with large grains is desirable in order to minimize grain boundaries and recombination during the operation of the device. Herein, a simple yet efficient approach is developed to synthesize perovskite films consisting of monolithic‐like grains with micrometer size through in situ deposition of octadecylamine functionalized single‐walled carbon nanotubes (ODA‐SWCNTs) onto the surface of the perovskite layer. The ODA‐SWCNTs form a capping layer that controls the evaporation rate of organic solvents in the perovskite film during the postthermal treatment. This favorable morphology in turn dramatically enhances the short‐circuit current density of the perovskite solar cells and almost completely eliminates the hysteresis. A maximum power conversion efficiency of 16.1% is achieved with an ODA‐SWCNT incorporated planar solar cell using (FA0.83MA0.17)0.95Cs0.05Pb(I0.83Br0.17)3 as light absorber. Furthermore, the perovskite solar cells with ODA‐SWCNT demonstrate extraordinary stability with performance retention of 80% after 45 d stability testing under high humidity (60–90%) environment. This work opens up a new avenue for morphology manipulation of perovskite films and enhances the device stability using carbon material. [ABSTRACT FROM AUTHOR]

LCN2 is involved in various cellular functions, including transport of small hydrophobic molecules, protection of MMP9 from proteolytic degradation, and regulating innate immunity. LCN2 is elevated in multiple human cancers, frequently being associated with tumor size, stage, and invasiveness. Our previous studies have shown that LCN2 expression could be induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in esophageal squamous cell carcinoma (ESCC) by the binding of five nucleoproteins (MISP, KLF10, KLF15, PPP1R18, and RXRβ) at a novel TPA-responsive element (TRE), at −152~−60 bp of the 5′ flanking region of the LCN2 promoter. However, much is unknown about whether these proteins can respond to TPA stimulation to regulate LCN2 transactivation and which cell signaling pathways mediate this process. In this study, expression plasmids encoding these five nucleoproteins were stably transfected into EC109 cells. Then, stable transfectant was characterized by a Dual-Luciferase Reporter Assay System. RT-PCR, real-time PCR, western blotting, specific kinase inhibitor treatment, and bioinformatics analyses were applied in this study. We found that MISP, KLF10, KLF15, PPP1R18, and RXRβ proteins could strongly respond to TPA stimulation and activate LCN2 transcriptional expression. MEK, ERK, JNK, and P38 kinases were involved in the LCN2 transactivation. Furthermore, the MEK-ERK signal pathway plays a major role in this biological process but does not involve PKCα signaling. [ABSTRACT FROM AUTHOR]

We report an efficient and practical iron-catalyzed hydrogen atom transfer protocol for assembling acetylenic motifs into functional alkenes. Diversities of internal alkynes could be obtained from readily available alkenes and acetylenic sulfones with excellent Markovnikov selectivity. An iron hydride hydrogen atom transfer catalytic cycle was described to clarify the mechanism of this reaction. [ABSTRACT FROM AUTHOR]

During germ cell development, epigenetic modifications undergo extensive remodeling. Abnormal epigenetic modifications usually result in germ cell loss and reproductive defect. Prmt5 (Protein arginine methyltransferase 5) encodes a protein arginine methyltransferase which has been demonstrated to play important roles in germ cell development during embryonic stages. In the present study, we found that Prmt5 was also abundantly expressed in male germ cells after birth. Inactivation of this gene by crossing with Stra8-Cre transgenic mice resulted in germ cell loss during spermatogenesis. Further study revealed that the germ cell development was grossly normal before P10. However, most of the germ cells in Prmt5Δ/f; Stra8-Cre mice were blocked at meiotic stage. The expression of meiosis associated genes was reduced in Prmt5Δ/f; Stra8-Cre testes compared to control testes at P10. γH2AX was detected in sex body of control germ cells at P12, whereas multiple foci were observed in Prmt5-deficient germ cells. Further study revealed that H4R3me2s was virtually absent in germ cells after Prmt5 inactivation. The results of this study indicate that Prmt5 also plays important roles in germ cell development during spermatogenesis. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports, for the first time, the second-order nonlinear optical (NLO) property of SbF3, a potential new NLO material in the infrared region. The compound SbF3 exhibits a powder second harmonic generation (SHG) of about 5.8 times that of potassium dihydrogen phosphate (KDP). The NLO property is phase- matchable evidenced by the study on the relationship between the powder SHG effect and the size of the powders. It also shows excellent transparency in the range of 0.29–12μm with high thermal stability. The band gap is calculated to be about 4.3eV. The origin of NLO property is discussed in terms of the crystal structure. [Copyright &y& Elsevier]