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In this paper, we discuss the existence of positive solutions to a discrete third-order three-point boundary value problem. Here, the weight function a(t)a\left(t) and the Green function G(t,s)G\left(t,s) both change their sign. Despite this, we also obtain several existence results of positive solutions by using the Guo-Krasnoselskii’s fixed-point theorem in a cone.

Quantum coherence by electronic quantum interference (QI) is significant to generate macroscopic photocurrent without heterostructures in both bulk and low‐dimensional materials. However, the coherent injection photocurrent by QI in low‐dimensional materials can be veiled by other linear or nonlinear optical effects. Herein, the coherent ultrafast injection photocurrent is investigated by coherent terahertz (THz) wave generation in multilayer rhenium disulfide (ReS2) at the nanometer scale under two‐color light excitation. It is observed that the THz radiation can be controlled by adjusting the relative phase between the two‐color lights under normal incidence. The experimental results demonstrate that the THz radiation of ReS2 is ascribed to the injection photocurrent from the electronic coherence of QI effect. However, the injection photocurrent is veiled by the nonlinear polarization, shift current, and drift current under oblique incidence. A method is proposed to isolate the pure injection photocurrent from these optical responses, based on the THz amplitude dependences on the pump power, incident polarization angle, and the relative phase between the two‐color lights. This work not only provides an all‐optical non‐contact method for understanding the quantum photocurrent in ReS2 but also promotes the quantum coherent control for solid‐state quantum devices. [ABSTRACT FROM AUTHOR]

The carrier dynamics of lead-free cesium tin halide perovskites are crucial for evaluating their potential as substitutes for lead-based perovskites. Herein, we investigate the ultrafast transport of hot carriers in CsSnBr3 microplates synthesized via chemical vapor deposition. We observe a significantly prolonged hot carrier cooling process lasting ∼50 ps, due to the hot-phonon bottleneck effect and the formation of large polarons. By employing transient absorption microscopy, we detect a time-dependent diffusion coefficient of hot carriers initially reaching up to 257.8 cm2·s−1, leading to a long average travel distance of ∼600 nm. Subsequently, it reveals a remarkable equilibrium carrier diffusion coefficient ranging from 12.7 to 16.5 cm2·s−1. These findings establish a fundamental basis for designing and advancing lead-free perovskite-based optoelectronic applications involving hot carriers. [ABSTRACT FROM AUTHOR]

Exploration of efficient, inexpensive, and stable electrocatalysts for the oxygen evolution reaction (OER) is of great significance for the energy crisis and environmental problems. Transition metal oxides (TMOs) are promising electrocatalysts for boosting OER. Herein, porous yolk@shell heterojunction nanospheres (denoted Co3O4@CeO2/Co3O4) were designed by interfaces and vacancies engineering as electrocatalysts for OER. Owing to the large specific surface area of the porous yolk@shell structure, high oxygen vacancy content, and good stability provided by CeO2, rapid charge transfer of Ce3+/Ce4+, and interaction of CeO2/Co3O4 heterojunctions, Co3O4@CeO2/Co3O4 nanospheres exhibit relatively excellent oxygen evolution performance (318 mV@10 mA cm–2) and long-term stability for 45 h in a 1.0 M KOH solution. This work provides a facile way to fabricate a kind of porous yolk@shell heterojunction nanomaterials for improving the OER performance of TMOs electrocatalysis. [ABSTRACT FROM AUTHOR]

Developing efficient electrocatalysts is very important for water electrolysis technology to deal with the energy crisis. The oxygen evolution reaction (OER) in the semireaction of electrolytic water is a crucial step. Herein, we report a facial strategy to fabricate the bird nest-like Fe3O4/CoOx (BN-Fe3O4/CoOx) nanosphere heterojunctions with amorphous/crystalline (a/c) structure through cation-exchange and subsequent calcination treatment in a reducing Ar/H2 atmosphere. Owing to its unique structure and the electron state near the heterogeneous interface, the BN-Fe3O4/CoOx nanosphere exhibits a very competitive overpotential of 286 mV at the current density of 10 mA cm–2 for OER with a low Tafel slope of 55.51 mV dec–1 in 1.0 M KOH, and long-term durability for more than 20 h. This work may provide an idea and a convenient method for the preparation of a/c-heterostructure electrocatalysts. [ABSTRACT FROM AUTHOR]

Background: Neuropathic pain is a prevalent and highly debilitating condition that impacts millions of individuals globally. Neuroinflammation is considered a key factor in the development of neuropathic pain. Accumulating evidence suggests that protein tyrosine phosphatase 1B (PTP1B) plays a crucial role in regulating neuroinflammation. Nevertheless, the specific involvement of PTP1B in neuropathic pain remains largely unknown. This study aims to examine the impact of PTP1B on neuropathic pain and unravel the underlying molecular mechanisms implicated. Methods: In the current study, we evaluated the paw withdrawal threshold (PWT) of male rats following spared nerve injury (SNI) to assess the presence of neuropathic pain. To elucidate the underlying mechanisms, western blotting, immunofluorescence, and electron microscopy techniques were employed. Results: Our results showed that SNI significantly elevated PTP1B levels, which was accompanied by an increase in the expression of endoplasmic reticulum (ER) stress markers (BIP, p‐PERK, p‐IRE1α, and ATF6) and phosphorylated NF‐κB in the spinal dorsal horn. SNI‐induced mechanical allodynia was impaired by the treatment of intrathecal injection of PTP1B siRNA or PTP1B‐IN‐1, a specific inhibitor of PTP1B. Moreover, the intrathecal administration of PTP1B‐IN‐1 effectively suppressed the expression of ER stress markers (BIP, p‐PERK/p‐eIF2α, p‐IRE1α, and ATF6), leading to the inhibition of NF‐κB, microglia, and astrocytes activation, as well as a decrease in pro‐inflammatory cytokines, including TNF‐α, IL‐6, and IL‐1β. However, these effects were reversed by intrathecal administration of tunicamycin (Tm, an inducer of ER stress). Additionally, intrathecal administration of Tm in healthy rats resulted in the development of mechanical allodynia and the activation of NF‐κB‐mediated neuroinflammatory signaling. Conclusions: The upregulation of PTP1B induced by SNI facilitates the activation of NF‐κB and glial cells via ER stress in the spinal dorsal horn. This, in turn, leads to an increase in the production of pro‐inflammatory cytokines, thereby contributing to the development and maintenance of neuropathic pain. Therefore, targeting PTP1B could be a promising therapeutic strategy for the treatment of neuropathic pain. [ABSTRACT FROM AUTHOR]

As the interest in "natural" and "safe" products grows, the use of natural products instead of synthetic preservatives to combat food spoilage and poisoning caused by microorganisms during processing and storage has become a prioritized option. The present research evaluated the antibacterial activity of the Mentha longifolia L. essential oil (MLEO) against several pathogenic bacteria, and the mechanism of action against methicillin‐resistant Staphylococcus aureus (MRSA). Gas Chromatography Quadrupole Time‐of‐Flight Mass Spectrometry (GC‐Q‐TOF MS) analysis suggested that main components of MLEO were carvone (47.39%) and limonene (12.48%). The oil showed considerable antibacterial activity with MIC values of 0.394–1.576 mg/mL, and could be a promising bactericide. Non‐targeted metabolomics analysis based on GC‐Q‐TOF MS identified 66 different metabolites, and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of these metabolites revealed that MLEO achieves the effects by affecting amino acid metabolism in MRSA. [ABSTRACT FROM AUTHOR]

We have investigated the thermal conductivity and vibration properties of TiS3 nanoribbon via micro-Raman spectroscopy. Based on the Raman spectra, the calculated temperature coefficients of the four A g 1 modes of the TiS3 nanoribbon sample are −0.0140, −0.0136, −0.0179, and −0.0172 cm−1 K−1, respectively, which are higher than that of traditional nanomaterials graphene and MoS2. The Raman frequency shift of TiS3 provides a powerful non-contact method to determine its local temperature rise, which is caused by the anharmonic coupling of phonons. From temperature coefficient and power coefficient values, the in-plane thermal conductivity of the TiS3 supported by SiO2/Si substrate has been calculated to be 187.2 ± 28.9 W/mK with weak anisotropy due to the substrate and size effects. This work paves a way to understand the heat conduction characteristics of transition metal trisulfide. [ABSTRACT FROM AUTHOR]

All-optical terahertz (THz) modulators have received tremendous attention due to their significant role in developing future sixth-generation technology and all-optical networks. Herein, the THz modulation performance of the Bi2Te3/Si heterostructure is investigated via THz time-domain spectroscopy under the control of continuous wave lasers at 532 nm and 405 nm. Broadband-sensitive modulation is observed at 532 nm and 405 nm within the experimental frequency range from 0.8 to 2.4 THz. The modulation depth reaches 80% under the 532 nm laser illumination with a maximum power of 250 mW and 96% under 405 nm illumination with a high power of 550 mW. The mechanism of the largely enhanced modulation depth is attributed to the construction of a type-II Bi2Te3/Si heterostructure, which could promote photogenerated electron and hole separation and increase carrier density dramatically. This work proves that a high photon energy laser can also achieve high-efficiency modulation based on the Bi2Te3/Si heterostructure, and the UV-Visible control laser may be more suitable for designing advanced all-optical THz modulators with micro-level sizes. [ABSTRACT FROM AUTHOR]

Cobalt-based spinel oxides are considered potential candidates for the oxygen evolution reaction (OER) due to their abundant valence changes and promising electrochemical activity, but their low intrinsic activity hinders their practical applications. Herein, we synthesize a series of CoCeMOx (M = Zn, Ni, Ru, Er, Mg, Mn, Sn) derived from CoCeM coordination-driven self-assembled aggregates (CDSAAs) using a general ion exchange and subsequent calcination method. Interestingly, CoCeMOx exhibit different morphologies from porous nanospheres, particle-stacked nanospheres, to hollow nanospheres as the third metal element is altered. Markedly, CoCeZnOx porous nanospheres (PNs) exhibit the best OER performance. The XPS results reveal that the existence of CeO2 and Zn2+ ions significantly increased the Co2+/Co3+ ratio and the content of oxygen vacancies in Co3O4. Furthermore, Co2+ can be used as highly reactive sites to form CoOOH and the high content of oxygen vacancies can optimize the oxygen-containing intermediate adsorption energy, both of which can effectively improve the OER performance. Therefore, well-designed CoCeZnOx PNs demonstrate high OER activity with a lower overpotential (η = 333 mV) than that of commercial RuO2 (344 mV) in 10 mA cm−2, a Tafel slope of 98 mV dec−1, and a long-term durability of 45 h. This work may provide some inspiration for the design of trimetallic oxide nanomaterials. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) have been widely explored and utilized in sodium-ion battery (SIB) anodes owing to their unique advantages, such as high theoretical specific capacity and low cost. However, their inherent defects, such as low electronic conductivity and severe volume expansion, seriously limit the further development of TMC-based anodes. Here, a novel composite material of CoSe2 nanoparticles (NPs) encapsulated in a dual one-dimensional (1D) carbon composite structure (CoSe2@CNTs/N-CNFs) was designed deliberately. Carbon nanotubes (CNTs) were grown in situ on the surface of carbon nanofibers (CNFs) with eco-friendly ethanol as the carbon source, while electrospun polyacrylonitrile (PAN) fibers were pyrolyzed to form nitrogen-doped nanofibers. It is noted that the wrapping with the composite carbon structure greatly improved the stability of CoSe2 NPs and solved its inherent defects as an anode material. When assembled into a half-cell, the CoSe2@CNTs/N-CNFs electrode exhibited outstanding sodium storage performance with a reversible specific capacity of 442 mA h g−1 after 100 cycles at 0.1 A g−1, as well as excellent rate performance, and the discharge specific capacity still reached 265 mA h g−1 even after 2000 cycles at a high current density of 5 A g−1. This study shows a new way to build a novel carbon substrate and TMC composite sodium storage material with low cost. [ABSTRACT FROM AUTHOR]

Lavandula angustifolia (LA) is a traditional Chinese herbal medicine commonly used as a folk medicine to treat brain diseases; in previous pharmacological studies, its water extract has been reported to have neuroprotective effects with the potential to be used in the treatment of Alzheimer's disease (AD). However, the material basis and the action mechanism of the effects were not clear. Hence, we have adopted a fast, low‐cost strategy to address this problem, through the following three processes: degreased lavender flower grains are extracted stepwise, main active sites are screened by zebrafish AD model, and key compounds and major pathways are identified using network pharmacology tools. The initial results show luteolin‐7‐glucoside, Apigenin‐7‐O‐glucoside, Salvianolic acid A and Rosmarinic acid can be used as the main active ingredient for lavender treatment of Alzheimer's disease. The major biological processes involved in these compounds include regulation of defense responses, decomposition of extracellular matrix, oxidative stress response, and peptidyl tyrosine phosphorylation. The most important metabolic pathways are cancer, IL‐17 signaling and age‐rage signaling indiabetic complications. Therefore, the strategies developed in this study are helpful to address the unclear material basis and mechanism of the effect of Chinese herbal medicine as well as form a bridge between traditional Chinese herbal medicine and modern medical language. [ABSTRACT FROM AUTHOR]

The chromatographic fingerprint of 14 batches of Artemisia rupestris L. samples were established in this study. The constituents of ten components in Artemisia rupestris L. were determined using quantitative analysis of multi-components by single marker (QAMS) and the external standard method (ESM). Due to their stability and accessibility, chlorogenic acid and linarin were used as references to calculate the relative correction factors (RCFs) of apigenin-C-6,8-pentoside-hexoside, apigenin-C-6,8-di-pentoside, luteolin, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, chrysosplenetin B, and sbsinthin, based on high-performance liquid chromatography (HPLC). The value calculated by QAMS was consistent with that of the ESM, and the reproducibility of RCFs was found to be reliable. In conclusion, simultaneous determination of the ten components by the QAMS method and chromatographic fingerprint analysis were feasible and accurate in evaluating the quality of Artemisia rupestris L. and can be used as reference in traditional Chinese medicine quality control. [ABSTRACT FROM AUTHOR]

Using simple methods to obtain efficient catalysts has been a long-standing goal for researchers. In this work, the employment of a one-pot pyrolysis reaction to achieve molecular confinement, has led to the preparation of ruthenium (Ru)-based nanoclusters in a carbon matrix. A unique feature of the synthetic approach employed is that solvent and substrates were calcined together. As solvent evaporates, during calcination, the substrates form a dense solid which has the effect of limiting the aggregation of Ru centers during the carbonization process. The catalyst prepared in this simple manner showed an impressively high activity with respect to the hydrogen/oxygen evolution reaction (HER/OER). The Ru nanoclusters (Ru NCs), as the hydrogen evolution reaction (HER) catalysts, require ultralow overpotentials of 5 mV and 5.1 mV at −10 mA·cm−2 in 1.0 M KOH, and 0.5 M H2SO4, respectively. Furthermore, the catalyst prepared by the one-pot method has higher crystallinity, a higher Ru content and an ultrafine cluster size, which contributes to its exceptional electrochemical performance. Meanwhile, the RuOX nanoclusters (RuOX NCs), obtained by oxidizing the aforementioned Ru NCs, exhibited good oxygen evolution reaction (OER) performance with an overpotential of 266 mV at 10 mA·cm−2. When applied to overall water splitting, Ru/RuOX nanoclusters as the cathode and anode catalysts can reach 10 mA·cm−2 at cell voltages of only 1.49 V in 1 M KOH. [ABSTRACT FROM AUTHOR]