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1.
Langmuir ; 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39498615

RESUMEN

This study employed polyoxometalate Co2Mo10 as a precursor and a two-step method to prepare carbon cloth-supported CuxS-CoS2-MoS2 materials. The morphology and structure of the materials were characterized using XRD, XPS, SEM, TEM, and other techniques. Interestingly, changes in the reducing gas during the calcination process could adjust the product morphology, thereby altering catalytic activity. Electrochemical results indicated that the CuxS-CoS2-MoS2 nanomaterials prepared under an NH3 atmosphere exhibited unique morphology and structural advantages. They demonstrated significant electrocatalytic activity for the hydrogen evolution reaction (HER) in alkaline and acidic electrolytes (overpotentials of 108 and 196 mV at a current density of 10 mA cm-2, lower than the overpotentials of 143 and 226 mV obtained under a H2-Ar atmosphere during calcination) and excellent long-term durability. These findings provide insights and methods for synthesizing multicomponent electrocatalysts with enhanced catalytic performance.

2.
Adv Mater ; : e2407244, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39363637

RESUMEN

Soft X-ray imaging is a powerful tool to explore the structure of cells, probe material with nanometer resolution, and investigate the energetic phenomena in the universe. Conventional soft X-ray image sensors are by and large Si-based charge coupled devices that suffer from low frame rates, complex fabrication processes, mechanical inflexibility, and required cooling below -60 °C. Here, a soft X-ray photodiode is reported based on low-cost metal halide perovskite with comparable performance to commercial Si-based device. Nanothrough network electrode minimized the optical loss due to the shadowing of insensitive layers, while a multidimensional perovskite heterojunction is generated to reduce the photo-generated carrier loss. This strategy promoted a record quantum efficiency of 8 × 103% without cooling, several orders of magnitude greater than the previously achieved. Flexible and curved soft X-ray imaging arrays are fabricated based on this high-performance device structure, demonstrating stable soft X-ray response and sharp imaging capabilities. This work highlights the low-cost and efficient perovskite photodiode as a strong candidate for the next-generation soft X-ray image sensors.

3.
Front Neurol ; 15: 1458066, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296955

RESUMEN

Objective: To assess the reliability and validity of the Chinese version of the Selective Control Assessment of the Lower Extremity (SCALE) in children with spastic cerebral palsy (CP). Methods: Forty-five children with spastic CP (mean age 7.29 years, SD 2.87 years, rang 4-16 years) were recruited. Internal consistency was measured using Cronbach's α, while test-retest and inter-rater reliability were evaluated using intra-class correlation coefficients (ICC). Construct validity was established through correlation and confirmatory factor analyses. Discriminative validity was assessed by comparing SCALE scores across varying GMFCS levels. Results: The Chinese version of SCALE demonstrates high internal consistency (Cronbach's α = 0.91) and good reliability with ICCs exceeding 0.76 for test-retest and inter-rater assessments. It shows significant correlations with GMFCS (r = -0.76, p < 0.001) and Fugl-Meyer scales (r = 0.79, p < 0.001), confirming its validity. Confirmatory factor analysis supports a well-fitting model (χ 2/df = 1.58, RMSEA = 0.08, SRMR <0.001, GFI = 0.98, AGFI = 0.90, CFI = 0.99, TLI = 0.98), with the latent variable's AVE at 0.59 and CR at 0.88. Discriminative validity is evident in significant differences across GMFCS levels (p < 0.001), notably between levels I and II, I and III, and I and IV (p < 0.05). Conclusion: The Chinese version of SCALE shows good reliability and validity for assessing lower limb selective movement control in children with spastic cerebral palsy in China. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=205380, identifier ChiCTR2400083880.

4.
Adv Sci (Weinh) ; 11(39): e2403647, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39146196

RESUMEN

The significant role of the cathodic binder in modulating mass transport within the catalyst layer (CL) of fuel cells is essential for optimizing cell performance. This investigation focuses on enhancing the membrane electrode assembly (MEA) through the utilization of a short-side-chain perfluoro-sulfonic acid (SSC-PFSA) ionomer as the cathode binder, referred to as SSC-MEA. This study meticulously visualizes the distinctive interpenetrating networks of ionomers and catalysts, and explicitly clarifies the triple-phase interface, unveiling the transport-friendly microstructure and transport mechanisms inherent in SSC-MEA. The SSC-MEA exhibits advantageous microstructural features, including a better-connected ionomer network and well-organized hierarchical porous structure, culminating in superior mass transfer properties. Relative to the MEA bonded by long-side-chain perfluoro-sulfonic acid (LSC-PFSA) ionomer, noted as LSC-MEA, SSC-MEA exhibits a notable peak power density (1.23 W cm-2), efficient O2 transport, and remarkable proton conductivity (65% improvement) at 65 °C and 70% relativity humidity (RH). These findings establish crucial insights into the intricate morphology-transport-performance relationship in the CL, thereby providing strategic guidance for developing highly efficient MEA.

5.
J Adv Res ; 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39079584

RESUMEN

INTRODUCTION: Nav1.6 is closely related to the pathology of Alzheimer's Disease (AD), and astrocytes have recently been identified as a significant source of ß-amyloid (Aß). However, little is known about the connection between Nav1.6 and astrocyte-derived Aß. OBJECTIVE: This study explored the crucial role of Nav1.6 in mediated astrocyte-derived Aß in AD and knockdown astrocytic Nav1.6 alleviates AD progression by promoting autophagy and lysosome-APP fusion. METHODS: A mouse model for astrocytic Nav1.6 knockdown was constructed to study the effects of astrocytic Nav1.6 on amyloidosis. The role of astrocytic Nav1.6 on autophagy and lysosome-APP(amyloid precursor protein) fusion was used by transmission electron microscope, immunostaining, western blot and patch clamp. Glial cell activation was detected using immunostaining. Neuroplasticity and neural network were assessed using patch-clamp, Golgi stain and EEG recording. Behavioral experiments were performed to evaluate cognitive defects. RESULTS: Astrocytic Nav1.6 knockdown reduces amyloidosis, alleviates glial cell activation and morphological complexity, improves neuroplasticity and abnormal neural networks, as well as promotes learning and memory abilities in APP/PS1 mice. Astrocytic Nav1.6 knockdown reduces itself-derived Aß by promoting lysosome- APP fusion, which is related to attenuating reverse Na+-Ca2+ exchange current thus reducing intracellular Ca2+ to facilitate autophagic through AKT/mTOR/ULK pathway. CONCLUSION: Our findings unveil the crucial role of astrocyte-specific Nav1.6 in reducing astrocyte-derived Aß, highlighting its potential as a cell-specific target for modulating AD progression.

6.
Environ Pollut ; 359: 124592, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39047887

RESUMEN

Cyanobacterial blooms are expanding world-wide in freshwater and marine environments, and can cause serious ecological and environmental issues, which also contribute to the spread of antibiotic resistance genes (ARGs). However, the mechanistic understanding of cyanobacteria-mediated resistance dynamics is not fully elucidated yet. We selected Microcystis aeruginosa as a model cyanobacteria to illustrate how cyanobacteria mediate the evolution and transfer processes of bacterial antibiotic resistance. The results show that the presence of cyanobacteria significantly decreased the abundance of antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARGs) by 3%-99% and 2%-18%, respectively. In addition, it clearly altered bacterial community structure, with the dominant genera evolving from Acinetobacter (27%) and Enterobacter (42%) to Porphyrobacter (59%). The abundance of ARGs positively correlated with Proteobacteria and Firmicutes, rather than Cyanobacteria, and Bacteroidetes. In the presence of cyanobacteria, the transfer events of bacterial resistance genes via conjugation were found to decrease by 10%-89% (p < 0.05). Surprisingly, we found an extradentary high transfer frequency (about 0.1) for the ARGs via plasmid conjugation from the bacteria into M. aeruginosa population. It confirmed the role of cyanobacterial population as the competent hosts to facilitate ARGs spreading. Our findings provide valuable information on the risk evaluation of ARGs caused by cyanobacterial blooms in aquatic environments, key for the protection and assessment of aquatic environmental quality.


Asunto(s)
Cianobacterias , Farmacorresistencia Bacteriana , Transferencia de Gen Horizontal , Microcystis , Farmacorresistencia Bacteriana/genética , Microcystis/genética , Cianobacterias/genética , Antibacterianos/farmacología , Conjugación Genética , Genes Bacterianos , Bacterias/genética , Bacterias/efectos de los fármacos
7.
J Colloid Interface Sci ; 672: 805-813, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875836

RESUMEN

Short-side-chain perfluorosulfonic acid (SSC-PFSA) ionomers with high ion-exchange-capacity are promising candidates for high-temperature proton exchange membranes (PEMs) and catalyst layer (CL) binders. The solution-casting method determines the importance of SSC-PFSA dispersion characteristics in shaping the morphology of PEMs and CLs. Therefore, a thorough understanding of the chain behavior of SSC-PFSA in dispersions is essential for fabricating high-quality PEMs and CLs. In this study, we have employed multiple characterization techniques, including dynamic light scatting (DLS), small-angle X-ray scattering (SAXS), and cryo-transmission electron microscope (Cryo-TEM), to fully study the chain aggregation behaviors of SSC-PFSA in water-ethanol solvents and elucidate the concentration-dependent self-assembly process. In dilute dispersions (2 mg/mL), SSC-PFSA assembles into mono-disperse rod-like aggregates, featuring a twisted fluorocarbon backbone that forms a hydrophobic stem, and the sulfonic acid side chains extending outward to suit the hydrophilic environment. As the concentration increases, the radius of rod particles increases from 1.47 to 1.81 nm, and the mono-disperse rod particles first form a "end-to-end" configuration that doubles length (10 mg/mL), and then transform into a swollen network structure in semi-dilute dispersion (20 mg/mL). This work provides a well-established structure model for SSC-PFSA dispersions, which is the key nanostructure to be inherited by PEMs.

8.
J Environ Manage ; 363: 121408, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38852411

RESUMEN

With the intensification of climate change, incorporating climate information into protected areas planning has become crucial in reducing biodiversity loss. However, the current natural reserve system in China does not take climate information into account. Therefore, we assessed the effectiveness of existing protected areas through climate refuge and connectivity rankings, and Zonation software was used to identify the ecological priority zone in China by combining climate indicators and human footprint. The results show that the current natural protected areas in China have certain limitations in dealing with climate change, and some protected areas may struggle to maintain their value in biodiversity conservation under climate change. Moreover, China still has lots of important areas that can maintain biodiversity under climate change, but most of them are not covered by protected areas. The results provide support for the planning of China's nature protected area system in response to climate change.


Asunto(s)
Biodiversidad , Cambio Climático , Conservación de los Recursos Naturales , China
9.
Langmuir ; 40(23): 12089-12096, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38804669

RESUMEN

Developing inexpensive, efficient, and stable catalysts is crucial for reducing the cost of electrolytic hydrogen production. Recently, polyoxometalates (POMs) have gained attention and widespread use due to their excellent electrocatalytic properties. This study designed and synthesized three composite materials, NF/PMonW12-n, by using phosphomolybdic-tungstic heteropolyacids as precursors to grow in situ on nickel foam via the hydrothermal process and subsequent calcination. Then, their catalytic performances are systematically investigated. This work demonstrates that the NF/PMonW12-n catalysts generate more low valent oxides under the synergistic effect of Mo and W, further enhancing activity for hydrogen evolution reaction (HER). Among these electrocatalysts, NF/PMo6W6 exhibits the perfect HER performance, η10 is only 74 mV. It also shows great stability during long-term electrolysis. The current study introduces a fresh approach for producing electrocatalysts that are both cost-effective and highly efficient.

10.
Angew Chem Int Ed Engl ; 63(24): e202403790, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38589294

RESUMEN

Assemblies of nanoparticles at liquid interfaces hold promise as dynamic "active" systems when there are convenient methods to drive the system out of equilibrium via crowding. To this end, we show that oversaturated assemblies of charged nanoparticles can be realized and held in that state with an external electric field. Upon removal of the field, strong interparticle repulsive forces cause a high in-plane electrostatic pressure that is released in an explosive emulsification. We quantify the packing of the assembly as it is driven into the oversaturated state under an applied electric field. Physiochemical conditions substantially affect the intensity of the induced explosive emulsification, underscoring the crucial role of interparticle electrostatic repulsion.

11.
Sci Total Environ ; 926: 172106, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38556015

RESUMEN

Sewage sludge land application is recognized as a strategy for recycling resource and replenishing soil nutrients. However, the subsequent greenhouse gas emissions following this practice are not yet fully understood, and the lack of quantitative research and field experiments monitoring these emissions hampers the establishment of reliable emission factors. This study investigated the greenhouse gas emission characteristics of sewage sludge land application through a field experiment that monitoring soil greenhouse gas fluxes. Seven nitrogen input treatments were implemented in a typical Bermuda grassland in China, with D and C representing the amendment of digested and composted sludge, respectively, at the nitrogen input rate of 0, 100, 200, and 300 kg N ha-1. Soil CH4, CO2, and N2O fluxes were measured throughout the entire experimental period, and soil samples from different treatments at various growth stages were analyzed. The results revealed that sewage sludge land application significantly increased soil N2O and CO2 emissions while slightly reducing soil CH4 uptake. The increased CO2 emissions were biogenic and carbon-neutral, mainly due to enhanced plant root respiration. The N2O emissions were the primary greenhouse gas emissions of sewage sludge land application, which were mainly concentrated in two 50-day periods following base and topdressing fertilization, respectively. N2O emissions following base fertilization by rotary tillage were substantially lower than those following topdressing fertilization. A logarithmic response relationship between N input rates and increased soil N2O emissions was observed, suggesting lower N2O emissions from sewage sludge land application compared to conventional N fertilizers at the same N input level. Future field experiments and meta-analysis are necessary to develop reliable greenhouse gas emission factors for sewage sludge land application.

12.
Sci Rep ; 14(1): 3630, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38351201

RESUMEN

Urban park management assessment is critical to park operation and service quality. Traditional assessment methods cannot comprehensively assess park use and environmental conditions. Besides, although social media and big data have shown significant advantages in understanding public behavior or preference and park features or values, there has been little relevant research on park management assessment. This study proposes a deep learning-based framework for assessing urban park intelligent management from macro to micro levels with comment data from social media. By taking seven parks in Wuhan City as the objects, this study quantitatively assesses their overall state and performance in facilities, safety, environment, activities, and services, and reveals their main problems in management. The results demonstrate the impacts of various factors, including park type, season, and specific events such as remodeling and refurbishment, on visitor satisfaction and the characteristics of individual parks and their management. Compared with traditional methods, this framework enables real-time intelligent assessment of park management, which can accurately reflect park use and visitor feedback, and improve park service quality and management efficiency. Overall, this study provides important reference for intelligent park management assessment based on big data and artificial intelligence, which can facilitate the future development of smart cities.

13.
Adv Mater ; 36(19): e2310435, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38386499

RESUMEN

An active droplet system, programmed to repeatedly move autonomously at a specific velocity in a well-defined direction, is demonstrated. Coulombic energy is stored in oversaturated interfacial assemblies of charged nanoparticle-surfactants by an applied DC electric field and can be released on demand. Spontaneous emulsification is suppressed by an increase in the stiffness of the oversaturated assemblies. Rapidly removing the field releases the stored energy in an explosive event that propels the droplet, where thousands of charged microdroplets are ballistically ejected from the surface of the parent droplet. The ejection is made directional by a symmetry breaking of the interfacial assembly, and the combined interaction force of the microdroplet plume on one side of the droplet propels the droplet distances tens of times its size, making the droplet active. The propulsion is autonomous, repeatable, and agnostic to the chemical composition of the nanoparticles. The symmetry-breaking in the nanoparticle assembly controls the microdroplet velocity and direction of propulsion. This mechanism of droplet propulsion will advance soft micro-robotics, establishes a new type of active matter, and introduces new vehicles for compartmentalized delivery.

15.
Small ; 20(15): e2308560, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37994305

RESUMEN

The in-plane packing of gold (Au), polystyrene (PS), and silica (SiO2) spherical nanoparticle (NP) mixtures at a water-oil interface is investigated in situ by UV-vis reflection spectroscopy. All NPs are functionalized with carboxylic acid such that they strongly interact with amine-functionalized ligands dissolved in an immiscible oil phase at the fluid interface. This interaction markedly increases the binding energy of these nanoparticle surfactants (NPSs). The separation distance between the Au NPSs and Au surface coverage are measured by the maximum plasmonic wavelength (λmax) and integrated intensities as the assemblies saturate for different concentrations of non-plasmonic (PS/SiO2) NPs. As the PS/SiO2 content increases, the time to reach intimate Au NP contact also increases, resulting from their hindered mobility. λmax changes within the first few minutes of adsorption due to weak attractive inter-NP forces. Additionally, a sharper peak in the reflection spectrum at NP saturation reveals tighter Au NP packing for assemblies with intermediate non-plasmonic NP content. Grazing incidence small angle X-ray scattering (GISAXS) and scanning electron microscopy (SEM) measurements confirm a decrease in Au NP domain size for mixtures with larger non-plasmonic NP content. The results demonstrate a simple means to probe interfacial phase separation behavior using in situ spectroscopy as interfacial structures densify into jammed, phase-separated NP films.

16.
Langmuir ; 40(1): 744-750, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38103033

RESUMEN

To explore, highly active electrocatalysts are essential for water splitting materials. Polyoxometalates (POMs) have drawn interesting attention in recent years due to their abundant structure and unique electrocatalytic properties. In this study, by using a POM-based precursor Co2Mo10, novel bimetallic sulfide (CoS2-MoS2) nanocomposites are rationally designed and synthesized under hydrothermal conditions. The incorporation of Co2+ to the host electrocatalyst could effectively increase the exposure of active sites of MoS2. Compared to pure MoS2, the CoS2-MoS2 nanocomposite exhibited a perfect hydrogen evolution reaction (HER) ability, for it merely requires overpotentials of 120 and 153 mV for 10 mA cm-2 working current density toward the HER in 1 M KOH and 0.5 M H2SO4 electrolyte systems, respectively. Additionally, the nanocomposite exhibited outstanding chemical stability and long-term durability. This study presents a novel strategy that utilizes POMs to enrich the exposed edge sites of MoS2, resulting in the preparation of efficient electrocatalysts.

17.
PeerJ Comput Sci ; 9: e1334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346724

RESUMEN

This study offers an integrated service management system for rural tourist information based on a cloud platform to address the three main issues of high platform concurrency, difficulty storing and managing data, and trouble sharing data functions. Three levels-data, process, and architecture-are considered in the analysis and design of the platform. The Hadoop data storage system makes possible the collection, storage, administration, and exchange of data functions for large amounts of heterogeneous data from many different sources by utilising Netty data transmission technology, hybrid data storage technology, and the Web Foundation. The results demonstrate that the system's response time is low, and the CPU consumption time and the average utilisation rate meet the actual needs. They resolve issues with the current rural tourism platforms application, such as the difficulty of data collection, the low rate of reuse, the low rate of sharing, the lack of timely updates, and severe island phenomena.

18.
Molecules ; 28(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36903478

RESUMEN

Chemical synthesis is state-of-the-art, and, therefore, it is generally based on chemical intuition or experience of researchers. The upgraded paradigm that incorporates automation technology and machine learning (ML) algorithms has recently been merged into almost every subdiscipline of chemical science, from material discovery to catalyst/reaction design to synthetic route planning, which often takes the form of unmanned systems. The ML algorithms and their application scenarios in unmanned systems for chemical synthesis were presented. The prospects for strengthening the connection between reaction pathway exploration and the existing automatic reaction platform and solutions for improving autonomation through information extraction, robots, computer vision, and intelligent scheduling were proposed.

19.
R Soc Open Sci ; 9(3): 211391, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35316948

RESUMEN

Iron phosphate (Fe-P) is a main phosphorus storage form, especially in phosphorus-polluted environments. The re-release of Fe-P is a problematic result during microalgal remediation. In this study, pre-incubated Chlorella vulgaris was cultured in a BG-11 culture medium with different amounts of Fe-P. The effects of Fe-P re-release on biomass, flocculation and removal of PO4 3- were investigated. The results indicated that C. vulgaris can promote the dissolution and release of Fe-P when the pH is 7, and the amount of Fe-P (ΔQ) released in 200 ml water reaches 0.055-0.45 mg d-1 under a C. vulgaris concentration of 5.6 × 105-8 × 105 cells ml-1. The growth of C. vulgaris was inhibited because of the flocculation behaviour of Fe3 + in the release stage, which is associated with a specific growth rate of 0.3-0.4 d-1 and a phosphorus removal rate below 30%. However, this process, in the long term, indicates a favourable transformation in which Fe-P becomes bioavailable under the action of C. vulgaris. Microalgae outbreaks may be triggered by persistent interactions between Fe-P and C. vulgaris. This study provides an important reference for the application of C. vulgaris in a Fe-P-rich environment.

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