•Combining nanomaterials and surface molecular imprinting for sensor preparation.•Taking carboxylation-modified SiO2 as the carrier to synthesize SMIPs.•Controllable morphology, thin blotting layer ...and less encapsulation of SiO2@MIP.•Using MWCNTs and AuNPs to improve electrode sensitivity and electron transport.•Simpler preparation, higher selectivity and lower cost of the SiO2@MIP sensor.
A molecularly imprinted sensor for highly sensitive and selective determination of dibutyl phthalate (DBP) was fabricated by combining multi-walled carbon nanotubes (MWCNTs) and Au nanoparticles (AuNPs) with surface molecularly imprinted polymer (SMIPs). The MWCNTs and AuNPs were designed to modify the electrode surface to accelerate the electron transfer rate and enhance the chemical stability. SMIPs were synthesized using SiO2 microspheres as carriers. By loading SMIPs capable of identifying DBP on the surface of modified electrodes of MWCNTs and AuNPs, an electrochemical sensor for detecting DBP was successfully constructed. After optimizing the experimental conditions, the modified electrode SiO2-COOH@MIP/AuNPs/MWCNTs/GCE can recognize DBP in the range of 10−7g L−1 to 10−2g L−1, and the detection limit achieved to 5.09 × 10−9 g L−1 (S/N = 3). The results demonstrate that the proposed MIP electrochemical sensor may be a promising candidate electrochemical strategy for detecting DBP in complex samples.
Surface-enhanced Raman scattering (SERS) has gained widespread use in molecule-level detection benefiting from its high sensitivity, nondestructive data acquisition, and capacity for providing ...molecular fingerprint information. However, the strong adhesion of target molecules to the substrate (known as the “memory effect”) inherently hinders the reusability of SERS substrates. Research has shown that self-cleaning SERS substrates based on versatile semiconductor materials with SERS enhancement capabilities and solar photocatalytic properties offer an effective platform for the sensitive detection and degradation of harmful molecules.
In this research, a resuable SERS-active substrate was facilely fabricated by anchoring silver nanoparticles (AgNPs) to the edges of MoS2 nanosheet decorated on ZnO nanorod arrays (NRAs). This innovative design exhibited a remarkable SERS enhancement factor (EF) of 4.6 × 107 and demonstrated significant solar photocatalytic efficiency. Such superior characteristics of ternary plasma heterojunction were ascribable to the synergistic effect of the “Schottky barrier” and “hot spots” between MoS2 and AgNPs, the inherent chemical enhancement proficiency of the MoS2/ZnO NRAs heterojunction, as well as the ultrafast electron transfer within the ternary heterojunction.
The developed ternary heterojunction substrate enabled highly sensitive SERS detection of trace amounts of organic molecules. Moreover, this SERS substrate exhibited self-cleaning and recyclability via solar-light-driven photocatalysis. This bifunctional recyclable SERS substrate proved capable of meeting various requirements for routine monitoring of environmental organic pollutants and provided a robust avenue for advancing energy utilization materials that serve as high-performance SERS sensors and catalysts.
•A novel ternary plasma heterojunction AgNPs/MoS2/ZnO NRAs was facile prepared.•The heterojunction showed superior performance on photocatalysis and SERS detection.•The synergistic effect of the EM and CM in AgNPs/MoS2/ZnO enhanced the SERS signal.•The composite exhibited optimal performance for visible-light degradation.•The recyclable SERS detection was realized through solar-driven photocatalysis.
Abnormalities in vocal expression during a depressed episode have frequently been reported in people with depression, but less is known about if these abnormalities only exist in special situations. ...In addition, the impacts of irrelevant demographic variables on voice were uncontrolled in previous studies. Therefore, this study compares the vocal differences between depressed and healthy people under various situations with irrelevant variables being regarded as covariates.
To examine whether the vocal abnormalities in people with depression only exist in special situations, this study compared the vocal differences between healthy people and patients with unipolar depression in 12 situations (speech scenarios). Positive, negative and neutral voice expressions between depressed and healthy people were compared in four tasks. Multiple analysis of covariance (MANCOVA) was used for evaluating the main effects of variable group (depressed vs. healthy) on acoustic features. The significances of acoustic features were evaluated by both statistical significance and magnitude of effect size.
The results of multivariate analysis of covariance showed that significant differences between the two groups were observed in all 12 speech scenarios. Although significant acoustic features were not the same in different scenarios, we found that three acoustic features (loudness, MFCC5 and MFCC7) were consistently different between people with and without depression with large effect magnitude.
Vocal differences between depressed and healthy people exist in 12 scenarios. Acoustic features including loudness, MFCC5 and MFCC7 have potentials to be indicators for identifying depression via voice analysis. These findings support that depressed people's voices include both situation-specific and cross-situational patterns of acoustic features.
Two-dimensional (2D) transition metal dichalcogenides (TMDCs) with layered structures provide a unique platform for exploring the effect of number of layers on their fundamental properties. However, ...the thickness scaling effect on the chemical properties of these materials remains unexplored. Here, we explored the chemically induced phase transition of 2D molybdenum disulfide (MoS2) from both experimental and theoretical aspects and observed that the critical electron injection concentration and the duration required for the phase transition of 2D MoS2 increased with decreasing number of layers. We further revealed that the observed dependence originated from the layer-dependent density of states of 2H-MoS2, which results in decreasing phase stability for 2H-MoS2 with increasing number of layers upon electron doping. Also, the much larger energy barrier for the phase transition of monolayer MoS2 induces the longer reaction time required for monolayer MoS2 as compared to multilayer MoS2. The layer-dependent phase transition of 2D MoS2 allows for the chemical construction of semiconducting-metallic heterophase junctions and, subsequently, the fabrications of rectifying diodes and all 2D field effect transistors and thus opens a new avenue for building ultrathin electronic devices. In addition, these new findings elucidate how electronic structures affect the chemical properties of 2D TMDCs and, therefore, shed new light on the controllable chemical modulations of these emerging materials.
Pemphigus is a severe autoimmune bullous dermatosis that affects the skin and/or mucosa, and it may be life-threatening without proper treatment. The guidelines and/or consensus statements for ...treatment vary widely between groups. We selected 6 guidelines and consensus statements established by different associations about the management of pemphigus vulgaris (PV) and/or pemphigus foliaceus (PF) to review, compare, and contrast the similarities and differences of these recommendations and provide optimal management suggestions to physicians. Corticosteroids remain a first-line therapy for pemphigus, but there are many differences in initial dose, tapering schedule, and management of relapse between different guidelines. Rituximab is a monoclonal antibody targeting CD20-positive B lymphocytes that is approved as a first-line therapy in moderate-to-severe pemphigus. Immunosuppressive agents, such as azathioprine (AZA) and mycophenolate mofetil (MMF), are also widely used as corticosteroid-sparing drugs, but the adjuvant applications and dosage regimens of different recommendations are not standardized. We attribute these differences to the clinical scoring adopted, the standards for disease severity evaluation, the publication year of each guideline, and local and regional healthcare differences.
Carbon quantum dots (CQDs) with stable physicochemical properties are one of the emerging carbon nanomaterials that have been studied in recent years. In addition to the excellent optical properties ...such as photoluminescence, photobleaching resistance and light stability, this material also has favorable advantages of good biocompatibility and easy functionalization, which make it an ideal raw material for constructing sensing equipment. In addition, CQDs can combined with other kinds of materials to form the nanostructured composites with unique properties, which provides new insights and ideas for the research of many fields. In the field of food analysis, emerging CQDs have been deeply studied in food composition analysis, detection and monitoring trace harmful substances and made remarkable research progress. This article introduces and compares the various methods for CQDs preparation and reviews its related sensing applications as a new material in food components analysis and food safety inspection in recent years. It is expected to provide a significant guidance for the further study of CQDs in the field of food analysis and detection.
Nitric oxide (NO) can induce plant disease resistance through signal transduction. The gamma-aminobutyric acid (GABA) shunt possesses different response modes for resisting different pathogens. ...However, the effect of the GABA shunt in NO-induced plant disease resistance is not clear. Herein, the role of the GABA shunt in the resistance of peach fruit induced by NO against Monilinia fructicola infection was investigated together with possible interaction pathways. NO treatment repressed the disease of peach fruit, increased the endogenous NO content, and enhanced the activities and gene expression of GABA shunt enzymes within 48 h, including glutamate decarboxylase (GAD), GABA transaminase (GABA-T) and succinic semialdehyde dehydrogenase (SSADH). However, the NO scavenger 2-(4-carboxyphenyl)− 4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) aggravated the disease of peach fruit, and inhibited the activities and gene expression of GABA shunt enzymes. The above results highlighted the importance of the GABA shunt in NO-induced disease resistance of peach fruit. It was noteworthy that the nitrosylated level of GAD4, GABA-T3 and SSADH was up-regulated at 6 and 12 h in NO-treated fruit compared with the control, which might be related to the enhanced GABA shunt activity. Additionally, NO treatment up-regulated the expression of glutamate receptor (PpGLR) and glutamate dehydrogenase (PpGDH), promoted Ca2+ influx, strengthened the activity of the tricarboxylic acid cycle (TCAC), and raised the ATP content and energy charge. Overall, the data indicated that NO treatment induced peach fruit disease resistance by activating the GABA shunt.
•NO treatment repressed the brown rot of peach fruit.•Activities and gene expression of GABA shunt enzymes were induced by NO treatment.•Nitrosylated level of GABA shunt enzymes was up-regulated by NO treatment.•NO treatment promoted the expression of PpGLRs and PpGDH, and Ca2+ influx.•NO treatment enhanced TCAC activity and increased ATP content and energy charge.
Advances in phototheranostics revolutionized glioma intraoperative fluorescence imaging and phototherapy. However, the lack of desired active targeting agents for crossing the blood–brain barrier ...(BBB) significantly compromises the theranostic efficacy. In this study, biomimetic proteolipid nanoparticles (NPs) with U.S. Food and Drug Administration (FDA)-approved indocyanine green (ICG) were constructed to allow fluorescence imaging, tumor margin detection, and phototherapy of orthotopic glioma in mice. By embedding glioma cell membrane proteins into NPs, the obtained biomimetic ICG-loaded liposome (BLIPO-ICG) NPs could cross BBB and actively reach glioma at the early stage thanks to their specific binding to glioma cells due to their excellent homotypic targeting and immune escaping characteristics. High accumulation in the brain tumor with a signal to background ratio of 8.4 was obtained at 12 h post-injection. At this time point, the glioma and its margin were clearly visualized by near-infrared fluorescence imaging. Under the imaging guidance, the glioma tissue could be completely removed as a proof of concept. In addition, after NIR laser irradiation (1 W/cm2, 5 min), the photothermal effect exerted by BLIPO-ICG NPs efficiently suppressed glioma cell proliferation with a 94.2% tumor growth inhibition. No photothermal damages of normal brain tissue and treatment-induced side effects were observed. These results suggest that the biomimetic proteolipid NP is a promising phototheranostic nanoplatform for brain-tumor-specific imaging and therapy.
The controlled synthesis of high‐quality multilayer (ML) MoS2 flakes with gradually shrinking basal planes by chemical vapor deposition (CVD) is demonstrated. These CVD‐grown ML MoS2 flakes exhibit ...much higher mobility and current density than mechanically exfoliated ML flakes due to the reduced contact resistance which mainly resulted from direct contact between the lower MoS2 layers and electrodes.
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