Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
1.
J Environ Manage ; 363: 121408, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852411

RESUMO

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.

2.
Langmuir ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804669

RESUMO

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.

3.
Angew Chem Int Ed Engl ; 63(24): e202403790, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38589294

RESUMO

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.

4.
Sci Total Environ ; 926: 172106, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38556015

RESUMO

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.

6.
Sci Rep ; 14(1): 3630, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351201

RESUMO

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.

7.
Adv Mater ; 36(19): e2310435, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38386499

RESUMO

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.

8.
Small ; 20(15): e2308560, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37994305

RESUMO

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.

9.
Langmuir ; 40(1): 744-750, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38103033

RESUMO

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.

10.
PeerJ Comput Sci ; 9: e1334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346724

RESUMO

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.

11.
Molecules ; 28(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36903478

RESUMO

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.

12.
R Soc Open Sci ; 9(3): 211391, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35316948

RESUMO

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.

14.
Front Pharmacol ; 12: 704715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675802

RESUMO

Background: Intervention of neuroinflammation in central nervous system (CNS) represents a potential therapeutic strategy for a host of brain disorders. The scorpion Buthus martensii Karsch (BmK) and its venom have long been used in the Orient to treat inflammation-related diseases such as rhumatoid arthritis and chronic pain. Scorpion venom heat-resistant peptide (SVHRP), a component from BmK venom, has been shown to reduce seizure susceptibility in a rat epileptic model and protect against cerebral ischemia-reperfusion injury. As neuroinflammation has been implicated in chronic neuronal hyperexcitability, epileptogenesis and cerebral ischemia-reperfusion injury, the present study aimed to investigate whether SVHRP has anti-inflammatory property in brain. Methods: An animal model of neuroinflammation induced by lipopolysacchride (LPS) injection was employed to investigate the effect of SVHRP (125 µg/kg, intraperitoneal injection) on inflammagen-induced expression of pro-inflammatory factors and microglia activation. The effect of SVHRP (2-20 µg/ml) on neuroinflammation was further investigated in primary brain cell cultures containing microglia as well as the immortalized BV2 microglia culture stimulated with LPS. Real-time quantitative PCR were used to measure mRNA levels of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß and IL-6 in hippocampus of animals. Protein levels of TNF-α, iNOS, P65 subunit of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) were examined by ELISA or western blot. Microglia morphology in animal hippocampus or cell cultures and cellular distribution of p65 were shown by immunostaining. Results: Morphological study demonstrated that activation of microglia, the main component that mediates the neuroinflammatory process, was inhibited by SVHRP in both LPS mouse and cellular model. Our results also showed dramatic increases in the expression of iNOS and TNF-α in hippocampus of LPS-injected mice, which was significantly attenuated by SVHRP treatment. In vitro results showed that SVHRP attenuated LPS-elicited expression of iNOS and TNF-α in different cultures without cell toxicity, which might be attributed to suppression of NF-κB and MAPK pathways by SVHRP. Conclusion: Our study demonstrates that SVHRP is able to inhibit neuroinflammation and microglia activation, which may underlie the therapeutic effects of BmK-derived materials, suggesting that BmK venom could be a potential source for CNS drug development.

15.
Water Environ Res ; 93(10): 2135-2148, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34013658

RESUMO

How environmental factors impact the release of pollutants from sediment is critical to ensure the safety of drinking water, especially when the seasons change. Here, we investigated the effect of water pH, temperature, and hydraulic disturbance on the release of heavy metals and nutrients from the sediment of drinking water reservoir. The results show that lower initial water pH promoted the Zn release, while low temperature enhanced the Mn flux after 15 days. Meanwhile, continuous disturbance caused more metals releasing from sediment than intermittent disturbance due to greater shear stress and turbulence effect. However, intermittent high-speed disturbance greatly altered the dynamic release of Zn from L-shaped curve to U-shape in water column. Moreover, lower water pH caused higher ammonium in water but lower nitrate since H+ restrained the nitrification. Yet, higher temperature inhibited the release of ammonium from sediment, which might relate to the accelerated mineralization of organic nitrogen and elevated dissolved oxygen caused by the algae growth. Notably, hydraulic disturbance with various intensity and duration greatly influenced the fluxes of various species of nitrogen and soluble phosphate in water column, because the disturbance facilitated the nitrogen and phosphorus exchanges between sediment-water and water-air interfaces. PRACTITIONER POINTS: Lower water pH induced Zn release, while low temperature gradually enhanced Mn level. More metals were released from sediment under continuous disturbance than intermittent disturbance. Lower water pH caused higher ammonium nitrogen in water but lower nitrate nitrogen. Higher temperature inhibited the release of ammonium nitrogen from sediment. Hydraulic disturbance greatly changed the release of different species of nitrogen and soluble phosphate from sediment.


Assuntos
Água Potável , Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Nutrientes , Fósforo/análise , Temperatura , Poluentes Químicos da Água/análise
16.
Dalton Trans ; 50(20): 6793-6796, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33978021

RESUMO

The synthesis and characterization of an indium-substituted quaternary heteropoly acid with a Keggin structure, H4[In(H2O)PW9Mo2O39]·11H2O (PMo9W2In), is reported. At 18 °C under 80% relative humidity, PMo9W2In displays protonic conductivity of 2.32 × 10-4 S cm-1 with an activation energy of 35.52 kJ mol-1, indicating that it is a potential solid protonic conductor following the vehicle mechanism. Its conductivity increases with temperature in the measured temperature range.

17.
Neurochem Res ; 46(7): 1830-1843, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33881662

RESUMO

Steroid receptor coactivator 1 (SRC-1) is one of the coactivators recruited by the nuclear receptors (NRs) when NRs are activated by steroid hormones, such as glucocorticoid. SRC-1 is abundant in hippocampus and hypothalamus and is also related to some major risk factors for depression, implicated by its reduced expression after stress and its effect on hypothalamus-pituitary-adrenal gland axis function. However, whether SRC-1 is involved in the formation of depression remains unclear. In this study, we firstly established chronic unpredictable stress (CUS) to induce depressive-like behaviors in mice and found that SRC-1 expression was reduced by CUS. A large number of studies have shown that neuroinflammation is associated with stress-induced depression and lipopolysaccharide (LPS) injection can lead to neuroinflammation and depressive-like behaviors in mice. Our result indicated that LPS treatment also decreased SRC-1 expression in mouse brain, implying the involvement of SRC-1 in the process of inflammation and depression. Next, we showed that the chronic unpredictable mild stress (CUMS) failed to elicit the depressive-like behaviors and dramatically promoted the expression of SRC-1 in brain of wild type mice. What's more, the SRC-1 knockout mice were more susceptible to CUMS to develop depressive-like behaviors and presented the changed expression of glucocorticoid receptor. However, SRC-1 deficiency did not affect the microglia activation induced by CUMS. Altogether, these results indicate a correlation between SRC-1 level and depressive-like behaviors, suggesting that SRC-1 might be involved in the development of depression induced by stress.


Assuntos
Depressão/metabolismo , Coativador 1 de Receptor Nuclear/deficiência , Estresse Psicológico/metabolismo , Animais , Células Cultivadas , Depressão/etiologia , Feminino , Elevação dos Membros Posteriores , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/metabolismo , Coativador 1 de Receptor Nuclear/metabolismo , Gravidez , Estresse Psicológico/complicações
18.
Br J Pharmacol ; 178(17): 3553-3569, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33886140

RESUMO

BACKGROUND AND PURPOSE: Microglia-related inflammation is associated with the pathology of Parkinson's disease. Functional voltage-gated sodium channels (VGSCs) are involved in regulating microglial function. Here, we aim to investigate the effects of scorpion venom heat-resistant synthesized peptide (SVHRSP) on 6-hydroxydopamine (6-OHDA)-induced Parkinson's disease-like mouse model and reveal its underlying mechanism. EXPERIMENTAL APPROACH: Unilateral brain injection of 6-OHDA was performed to establish Parkinson's disease mouse model. After behaviour test, brain tissues were collected for morphological analysis and protein/gene expression examination. Primary microglia culture was used to investigate the role of sodium channel Nav 1.6 in the regulation of microglia inflammation by SVHRSP. KEY RESULTS: SVHRSP treatment attenuated motor deficits, dopamine neuron degeneration, activation of glial cells and expression of pro-inflammatory cytokines induced by 6-OHDA lesion. Primary microglia activation and the production of pro-inflammatory cytokines induced by lipopolysaccharide (LPS) were also suppressed by SVHRSP treatment. In addition, SVHRSP could inhibit mitogen-activated protein kinases (MAPKs) pathway, which plays pivotal roles in the pro-inflammatory response. Notably, SVHRSP treatment suppressed the overexpression of microglial Nav 1.6 induced by 6-OHDA and LPS. Finally, it was shown that the anti-inflammatory effect of SVHRSP in microglia was Nav 1.6 dependent and was related to suppression of sodium current and probably the consequent Na+ /Ca2+ exchange. CONCLUSIONS AND IMPLICATIONS: SVHRSP might inhibit neuroinflammation and protect dopamine neurons via down-regulating microglial Nav 1.6 and subsequently suppressing intracellular Ca2+ accumulation to attenuate the activation of MAPKs signalling pathway in microglia.


Assuntos
Microglia , Venenos de Escorpião , Animais , Citocinas , Temperatura Alta , Lipopolissacarídeos/toxicidade , Camundongos , Oxidopamina , Venenos de Escorpião/toxicidade
19.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602813

RESUMO

The assembly and jamming of magnetic nanoparticles (NPs) at liquid-liquid interfaces is a versatile platform to endow structured liquid droplets with a magnetization, i.e., producing ferromagnetic liquid droplets (FMLDs). Here, we use hydrodynamics experiments to probe how the magnetization of FMLDs and their response to external stimuli can be tuned by chemical, structural, and magnetic means. The remanent magnetization stems from magnetic NPs jammed at the liquid-liquid interface and dispersed NPs magneto-statically coupled to the interface. FMLDs form even at low concentrations of magnetic NPs when mixing nonmagnetic and magnetic NPs, since the underlying magnetic dipole-driven clustering of magnetic NP-surfactants at the interface produces local magnetic properties, similar to those found with pure magnetic NP solutions. While the net magnetization is smaller, such a clustering of NPs may enable structured liquids with heterogeneous surfaces.

20.
Chemosphere ; 265: 129068, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33257050

RESUMO

Endogenous pollution from sediments is gradually becoming a critical pollution source of the drinking water reservoir. Odorants can be released from sediments into the overlying water which further deteriorate the water quality of the drinking water reservoir. In this work, we set the sediment-overlying water systems under various water pH (6.5, 8 and 9), temperature (4, 20 and 30 °C) during 30 days and intermittent or continuous hydraulic disturbances (at 100 r/min or 200 r/min) in 5 days, and investigated the dynamic release of odorants from the drinking water reservoir sediments via using headspace solid-phase microextraction (HSPME) and gas chromatography-mass spectrometry (GC-MS). The result shows that weakly alkaline environment slightly but not significantly increased the concentration of dimethyl disulfide (DMDS) in the overlying water. Furthermore, low temperature promoted the release of bis(2-chloroisopropyl) ether (BCIE) and geosmin to 108.36 and 18.98 ng/L, respectively, while high temperature facilitated the DMDS release to 20.33 ng/L. Notably, hydraulic disturbances drastically elevated the level of seven odorants released from the sediments. Specially, benzaldehyde exhibited highest concentration at 260.50 ng/L. The continuous disturbance greatly enhanced the release of benzaldehyde, DMDS, dimethyl trisulfide (DMTS), BCIE and 1,4-dichloro-benzene (1,4-DCB) from sediments with a positive disturbance speed-dependence. However, the intermittent disturbance promoted higher level of geosmin in the overlying water compared to the continuous disturbance. Only continuous hydraulic disturbance at high speed could lead to the release of ethylbenzene from sediments, which was up to 4.89 ng/L in 12 h.


Assuntos
Água Potável , Poluentes Químicos da Água , China , Água Potável/análise , Sedimentos Geológicos , Concentração de Íons de Hidrogênio , Odorantes/análise , Temperatura , Poluentes Químicos da Água/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA