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1.
Front Bioeng Biotechnol ; 12: 1346404, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737539

RESUMO

Objective: Titanium implants are widely used in surgeries for their biocompatibility and mechanical properties. However, excessive titanium particle release can cause implant failure. This study explores Atomic Layer Deposition (ALD) to coat commercially pure titanium (Cp-Ti) with TiO2, aiming to improve its frictional and corrosion resistance while reducing particle release. By comparing TiO2 films with varying ALD cycle numbers, we assess surface properties, particle release, friction, and corrosion performance, providing insights into mitigating particle release from implants. Methods: Cp-Ti surfaces were prepared and coated with TiO2 films of 100, 300, and 500 ALD cycles. Surface characterization involved SEM, EDX, and XRD. Friction was tested using SEM, nanoindentation, and ICP-MS. Corrosion resistance was evaluated through immersion tests and electrochemical analysis. Cytotoxicity was assessed using BMSCs. Results: Surface characterization revealed smoother surfaces with increased ALD cycles, confirming successful TiO2 deposition. Friction testing showed reduced friction coefficients with higher ALD cycles, supported by nanoindentation results. Corrosion resistance improved with increasing ALD cycles, as evidenced by electrochemical tests and reduced titanium release. Cytotoxicity studies showed no significant cytotoxic effects. Conclusion: ALD-coated TiO2 films significantly enhance frictional and corrosion resistance of titanium implants while reducing particle release. The study underscores the importance of ALD cycle numbers in optimizing film performance, offering insights for designing implants with improved properties.

2.
Talanta ; 275: 126180, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703480

RESUMO

Organic Electrochemical Transistors (OECTs) are integral in detecting human bioelectric signals, attributing their significance to distinct electrochemical properties, the utilization of soft materials, compact dimensions, and pronounced biocompatibility. This review traverses the technological evolution of OECT, highlighting its profound impact on non-invasive detection methodologies within the biomedicalfield. Four sensor types rooted in OECT technology were introduced: Electrocardiogram (ECG), Electroencephalogram (EEG), Electromyography (EMG), and Electrooculography (EOG), which hold promise for integration into wearable detection systems. The fundamental detection principles, material compositions, and functional attributes of these sensors are examined. Additionally, the performance metrics and delineates viable optimization strategies for assorted physiological electrical detection sensors are discussed. The overarching goal of this review is to foster deeper insights into the generation, propagation, and modulation of electrophysiological signals, thereby advancing the application and development of OECT in medical sciences.


Assuntos
Transistores Eletrônicos , Humanos , Eletromiografia/métodos , Eletrocardiografia/métodos , Técnicas Eletroquímicas/métodos , Eletroculografia/métodos , Eletroencefalografia
3.
J Environ Manage ; 358: 120888, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615399

RESUMO

Oil dispersion, a crucial process in oil transport, involves the detachment of oil droplets from slicks and their introduction into the water column, influencing subsequent oil migration and transformation. This study examines oil dispersion, considering characteristics, stability, and mechanisms, while evaluating the impact of dispersants and salinity. Results show the significant role of surfactant type in dispersants on oil dispersion characteristics, with anionic surfactants exhibiting higher sensitivity to salinity changes compared to nonionic surfactants. The dispersion efficiency varies with salinity, with anionic surfactants performing better in low salinity (<20‰) and nonionic surfactants showing superior performance at 30-35‰ salinities. Rheological analysis illustrates the breakup and coalescence of oil droplets within the shear rates of breaking waves. An increase in interfacial film rigidity impedes the coalescence of oil droplets, contributing to the dynamic stability of the oil-water hybrid system. The use of GM-2, a nonionic dispersant, results in the formation of a solid-like interface, characterized by increased elastic modulus, notably at 20‰ salinity. However, stable droplet size distribution (DSD) at 35‰ salinity for 60 h suggests droplets can remain dispersed in seawater. The enhancement of stability of oil dispersion is interpreted as the result of two mechanisms: stabilizing DSD and developing the strength of viscoelastic interfacial film. These findings offer insights into oil dispersion dynamics, highlighting the importance of surfactant selection and salinity in governing dispersion behavior, and elucidating mechanisms underlying dispersion stability.


Assuntos
Tensoativos , Tensoativos/química , Poluição por Petróleo , Salinidade , Reologia , Petróleo , Água do Mar/química
4.
BMC Med Imaging ; 24(1): 45, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360550

RESUMO

BACKGROUND: Tumor mutational burden (TMB) is one of the most significant predictive biomarkers of immunotherapy efficacy in non-small cell lung cancer (NSCLC). Radiomics allows high-throughput extraction and analysis of advanced and quantitative medical imaging features. This study develops and validates a radiomic model for predicting TMB level and the response to immunotherapy based on CT features in NSCLC. METHOD: Pre-operative chest CT images of 127 patients with NSCLC were retrospectively studied. The 3D-Slicer software was used to outline the region of interest and extract features from the CT images. Radiomics prediction model was constructed by LASSO and multiple logistic regression in a training dataset. The model was validated by receiver operating characteristic (ROC) curves and calibration curves using external datasets. Decision curve analysis was used to assess the value of the model for clinical application. RESULTS: A total of 1037 radiomic features were extracted from the CT images of NSCLC patients from TCGA. LASSO regression selected three radiomics features (Flatness, Autocorrelation and Minimum), which were associated with TMB level in NSCLC. A TMB prediction model consisting of 3 radiomic features was constructed by multiple logistic regression. The area under the curve (AUC) value in the TCGA training dataset was 0.816 (95% CI: 0.7109-0.9203) for predicting TMB level in NSCLC. The AUC value in external validation dataset I was 0.775 (95% CI: 0.5528-0.9972) for predicting TMB level in NSCLC, and the AUC value in external validation dataset II was 0.762 (95% CI: 0.5669-0.9569) for predicting the efficacy of immunotherapy in NSCLC. CONCLUSION: The model based on CT radiomic features helps to achieve cost effective improvement in TMB classification and precise immunotherapy treatment of NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Radiômica , Tomografia Computadorizada por Raios X/métodos , Biomarcadores Tumorais , Imunoterapia
5.
J Affect Disord ; 352: 321-332, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302068

RESUMO

BACKGROUND: Burnout has received considerable attention in recent years because of the adverse consequences for people. Theoretical perspectives propose that problematic internet use is a significant potential risk for burnout. Despite a plethora of studies showing a positive association between problematic internet use and burnout, there remains a contentious debate regarding the extent and direction of this association. METHODS: This study aims to perform a three-level meta-analysis to evaluate the strength of the relationship between problematic internet use and burnout through a quantitative synthesis of eligible studies published until April 2023. RESULTS: A total of 42 studies with 54,121 participants and 103 effect sizes were identified. The results indicated a positive, moderate, and significant association between problematic internet use and burnout. Furthermore, the subgroup analysis found that this association was moderated by population, dimension of burnout, and the measure of burnout, however, some study features (i.e., region, type of problematic internet use, gender, and publication year) could not explain the heterogeneity across individual studies. LIMITATIONS: Studies included in the current meta-analysis mainly used cross-sectional designs, which limited the potential to make inferences on the causal relationship between problematic internet use and burnout. CONCLUSIONS: Individuals with problematic internet use have exhibited higher levels of burnout. Overall, these findings develop a deeper understanding of this association between problematic internet use and burnout and have implications for the direction of future research and interventions.


Assuntos
Esgotamento Profissional , Uso da Internet , Humanos , Estudos Transversais , Esgotamento Psicológico , Esgotamento Profissional/epidemiologia , Inquéritos e Questionários , Internet
6.
Dev Psychol ; 60(1): 170-186, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37971829

RESUMO

It is theoretically plausible that social anxiety (SA) and social relationships (SR) can influence each other. However, the available empirical evidence is inconsistent, leading to substantial uncertainty regarding the cross-lagged relations between SA and SR. This meta-analysis systematically integrates data from 107 longitudinal studies, comprising 110 independent samples and involving a total of 115,133 participants from childhood to adulthood. Four types of SR were assessed: family-related, school-related, romantic, and general relationships. One-stage meta-analytic structural equation modeling was applied to fit four cross-lagged panel models and to test potential moderators. No significant publication bias was detected. Effect size analyses revealed that prior SA significantly and negatively predicted quality of all types of SR. Family-related and general relationships each predicted prospective SA symptoms, but school-related and romantic relationships did not. No moderators were identified in analyses of family-related and romantic relationships. However, the publication year, sample age, gender, reporter, and time lag played a moderating role in analyses of school-related and general relationships. These findings suggest that SA is a crucial factor undermining SR and that dysfunctional family and general relationships also contribute to the exacerbation of SA symptoms. The strengths, limitations, and future directions of this study are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Medo , Relações Interpessoais , Humanos , Criança , Adolescente , Adulto Jovem , Estudos Prospectivos , Ansiedade , Estudos Longitudinais
7.
J Hazard Mater ; 465: 133187, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38104519

RESUMO

A quantitative understanding of spilled oil transport in a nearshore environment is challenging due to the complex physicochemical processes in aqueous conditions. The physicochemical processes involved in oil sinking mainly include oil dispersion, sediment settling, and oil-sediment interaction. For the first time, this work attempts to address the sinking mechanism in petroleum contaminant transport using structural causal models based on observed data. The effects of nearshore salinity distribution from the estuary to the ocean on those three processes are examined. The causal inference reveals sediment settling is the crucial process for oil sinking. Salinity indirectly affects oil sinking by promoting sediment settling rather than directly affecting oil-sediment interaction. The increase of salinity from 0‰ to 35‰ provides a natural enhancement for sediment settling. Notably, unbiased causal effect estimates demonstrate the strongest positive causal effect on the settling efficiency of sediments is posed by increasing oil dispersion effectiveness, with a normalized value of 1.023. The highest strength of the causal relationship between oil dispersion and sediment settling highlights the importance of the dispersing characteristics of spilled oil to sediment-facilitated oil transport. The employed logic, a data-driven method, will shed light on adopting advanced causal inference tools to unravel the complicated contaminants' transport.

8.
Am J Transl Res ; 15(8): 5331-5338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692940

RESUMO

PURPOSE: To clarify the association of serum alpha-fetoprotein (AFP) with inflammatory markers interleukin (IL)-6 and tumor necrosis factor (TNF)-α in patients with chronic hepatitis B (CHB) during the immune-clearance phase in Eastern China. METHODS: This research selected 60 CHB patients during the immune clearance phase who tested positive for AFP, including 32 cases treated by non-antiviral therapy (experimental group) and 28 cases treated by antiviral therapy (positive control group). Another 30 cases tested negative for AFP were set as a negative control group. The correlations of serum AFP with IL-6 and TNF-α in patients were analyzed. RESULTS: HBV DNA clearance in patients receiving antiviral therapy, in both the positive or negative control groups, was not significantly related to other clinical data. In the experimental group, a positive correlation of HBV DNA clearance with serum AFP level (r=0.5126, P=0.0027), alanine aminotransferase (r=0.3924, P=0.0263), and total bilirubin (r=0.5126, P=0.0027) was found. The experimental and positive control groups exhibited elevated serum IL-6 and TNF-α contents versus the negative control group (P<0.05). A positive association of AFP with IL-6 and TNF-α was also identified. CONCLUSION: Serum AFP level is positively related to IL-6 and TNF-α levels in CHB patients during the immune-clearance phase.

9.
Medicine (Baltimore) ; 102(39): e35305, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773825

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that poses a significant threat to a patient's quality of life. Commonly used drugs include glucocorticoids, nonsteroidal anti-inflammatory drugs, disease-modifying antirheumatic drugs, and biological agents; however, there are associated side effects. Complementary and alternative medicines can play positive roles. Bibliometric analysis of herbal medicines for RA has been conducted, but current research trends in nonpharmaceutical traditional Chinese medicine (TCM) therapies for the treatment of RA have not been studied. Here, we conducted a bibliometric analysis of the application of nonpharmaceutical TCM therapies for RA over the last 20 years. METHODS: We retrieved relevant literature from the Web of Science Core Collection database and used VOSviewer and CiteSpace software for analysis. Visualized maps were then generated to display the relationships between the author, country, institution, and keywords. RESULTS: A total of 567 articles were included in the final analysis. The number of annual publications on nonpharmaceutical TCM interventions for RA increased over the study period. The journal with the highest number of publications on this topic was Evidence-based Complementary and Alternative Medicine; however, Cochrane Database of Systematic Reviews had the most citations. Collaborations were observed among worldwide institutions, with the People's Republic of China playing a dominant role in the research on treatment of RA using nonpharmaceutical TCM therapies. Ernst E was the most productive author, with 11 articles, whereas Green S had the highest number of citations (287) at the time of retrieval. Specific improvements in the efficacy and selection of nonpharmaceutical therapies were the main research hotspots based on citation burst analysis. CONCLUSION: This study characterizes the trends in the literature for nonpharmaceutical TCM therapy for RA over the past 20 years; showcasing the current research status for relevant researchers and their teams and providing a reference for future research directions.


Assuntos
Artrite Reumatoide , Medicina Tradicional Chinesa , Humanos , Qualidade de Vida , Revisões Sistemáticas como Assunto , Bibliometria , Artrite Reumatoide/tratamento farmacológico
10.
Anal Chim Acta ; 1278: 341760, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37709422

RESUMO

In this work, a sandwich-type electrochemiluminescence (ECL) system was constructed for the detection of CA15-3. Gold-silver bimetallic nanoclusters (Au-Ag BNCs) with zein as a protective ligand were synthesized, and the excellent ECL performance of this material was demonstrated for the first time. Zein carrying a variety of groups that ligated with Au-Ag BNCs, forming a protective shell of zein, effectively prevented clusters from aggregating or growing into larger nanoparticles. The synergistic effect of the bimetal promotes the ECL emission, making this nanoscale material an ideal ECL probe. GO-PANI, which effectively promoting the production of sulfate radicals of the co-reactant and significantly increasing the ECL strength, was a good sensing platform for antibody immobilization. Consequently, we constructed an ECL sensor with GO-PANI as the sensing platform and Au-Ag BNCs@zein as the ECL probe, with a detection range of 0.001-100 U mL-1 and a detection limit of 0.0003 U mL-1, provided a strong support for the sensor for future CA15-3 detection applications.


Assuntos
Nanopartículas , Zeína , Anticorpos , Ouro , Mucina-1
11.
Nat Commun ; 14(1): 5568, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689758

RESUMO

Van der Waals dielectrics are fundamental materials for condensed matter physics and advanced electronic applications. Most dielectrics host isotropic structures in crystalline or amorphous forms, and only a few studies have considered the role of anisotropic crystal symmetry in dielectrics as a delicate way to tune electronic properties of channel materials. Here, we demonstrate a layered anisotropic dielectric, SiP2, with non-symmorphic twofold-rotational C2 symmetry as a gate medium which can break the original threefold-rotational C3 symmetry of MoS2 to achieve unexpected linearly-polarized photoluminescence and anisotropic second harmonic generation at SiP2/MoS2 interfaces. In contrast to the isotropic behavior of pristine MoS2, a large conductance anisotropy with an anisotropy index up to 1000 can be achieved and modulated in SiP2-gated MoS2 transistors. Theoretical calculations reveal that the anisotropic moiré potential at such interfaces is responsible for the giant anisotropic conductance and optical response. Our results provide a strategy for generating exotic functionalities at dielectric/semiconductor interfaces via symmetry engineering.

12.
Behav Sci (Basel) ; 13(8)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37622819

RESUMO

In today's information society, with the growing integration of the Internet into individuals' lives, problematic Internet use (PIU) among adolescents has become more prevalent. Therefore, we conducted this study to investigate the correlation between active parental mediation and PIU in adolescents, as well as the potential mediating roles of parent-child relationship and adolescents' hiding online behavior. A total of 539 middle school students (mean age = 13.384) were recruited for this study and participated by completing a series of paper-and-pencil questionnaires. The findings indicated a significant negative relationship between active parental mediation and PIU. Furthermore, both the mediating role of the parent-child relationship and the role of hiding online behavior were found to be significant. Specifically, the mediating role is comprised of two paths: the independent mediating role of the parent-child relationship, and the sequential mediating role involving both the parent-child relationship and hiding online behavior. The study contributes an innovative theoretical perspective to deepen the understanding of the formation mechanism of PIU. Moreover, it offers practical empirical insights for the prevention and intervention of PIU among adolescents.

13.
Biosensors (Basel) ; 13(8)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37622891

RESUMO

In lower-limb rehabilitation, human action recognition (HAR) technology can be introduced to analyze the surface electromyography (sEMG) signal generated by movements, which can provide an objective and accurate evaluation of the patient's action. To balance the long cycle required for rehabilitation and the inconvenient factors brought by wearing sEMG devices, a portable sEMG signal acquisition device was developed that can be used under daily scenarios. Additionally, a mobile application was developed to meet the demand for real-time monitoring and analysis of sEMG signals. This application can monitor data in real time and has functions such as plotting, filtering, storage, and action capture and recognition. To build the dataset required for the recognition model, six lower-limb motions were developed for rehabilitation (kick, toe off, heel off, toe off and heel up, step back and kick, and full gait). The sEMG segment and action label were combined for training a convolutional neural network (CNN) to achieve high-precision recognition performance for human lower-limb actions (with a maximum accuracy of 97.96% and recognition accuracy for all actions reaching over 97%). The results show that the smartphone-based sEMG analysis system proposed in this paper can provide reliable information for the clinical evaluation of lower-limb rehabilitation.


Assuntos
Aplicativos Móveis , Smartphone , Humanos , Eletromiografia , Reconhecimento Automatizado de Padrão , Terapia por Exercício
14.
Chemosphere ; 340: 139803, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37579821

RESUMO

Rapid and efficient recovery of oil spill is the key link for oil spill remediation, and also a great challenge. Here, the organogelator-polymerized porous matrix composed of adsorbents and organogelators can provide a new strategy for solving this problem. The gelling mechanism of aluminum 12-hydroxystearate (Al HSA) to form spherical nano micelles in solvents was investigated via UV-vis, FT-IR, and XRD. A creative method for aluminum soap-lignin gelator (OTS-AL/Al HSA) syntheses was put forward through the saponification of 12-hydroxystearic acid (HSA) and lignin via epichlorohydrin (ECH) crosslinking. By adjusting the ECH content, the growth of Al HSA nanoparticles (15-40 nm) on lignin can be realized, and the accordingly increased roughness endowed gelator with better hydrophobicity (WCA of 134.6°) before octadecyltrichlorosilane (OTS) modification. Thanks to the porous structures, the gelator powder exhibited a high sorption capacity in the range of 3.5-5.2 g g-1 for oils and organic solvents. Rheological studies demonstrated high mechanical strength of gels (>1.6 × 105 pa) and the gelator still retained 70% sorption capacity after 6 gelation-distillation cycles. The gelation characteristics of OTS-AL/Al HSA were attributed to the rapid sorption of oils by lignin and the self-assembly of Al HSA nano micelles on lignin to form an aggregated network structure trapping oils, thus realizing the synergistic effect of oil sorption-gelation.


Assuntos
Lignina , Água , Água/química , Pós , Alumínio , Sabões , Espectroscopia de Infravermelho com Transformada de Fourier , Óleos/química , Solventes/química , Géis/química
15.
Environ Sci Pollut Res Int ; 30(40): 92107-92122, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37480536

RESUMO

Population aging, economic globalization, and economic growth simultaneously cause changes in environmental quality, but so far no studies have integrated these key factors into the same environmental policy framework. Thus, this study uses the more robust Westerlund cointegration test and the augmented mean group (AMG) estimator (robust to cross-sectional dependence (CD), heterogeneity, and endogeneity) to estimate the long-term relationship between population aging, economic globalization, economic growth, and per capita carbon emissions in East Asian countries during the period 1975-2018. The analysis results reflect that population aging significantly reduces the long-term per capita carbon emissions of specific East Asian countries. However, energy generation and economic globalization make significant contributions to long-run per capita carbon emissions. Moreover, the impact of economic growth on long-term per capita carbon emissions is significantly positive, while the impact of square of economic growth on long-run per capita carbon emissions is significantly negative, thus validating the inverted U-shaped environmental Kuznets curve (EKC) hypothesis for specific East Asian countries. The results of the causality test indicated a two-way causality between energy generation and per capita carbon dioxide emission, supporting the feedback hypothesis. There is also a two-way causal relationship between aging population and per capita carbon dioxide emission. Policy recommendations are discussed in response to the empirical findings of this study.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Idoso , Humanos , Envelhecimento , Estudos Transversais , População do Leste Asiático , Internacionalidade
16.
Medicine (Baltimore) ; 102(23): e34019, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37335631

RESUMO

Lung cancer in never smokers (LCNS) has been considered as a separate disease and the 7th cause of cancer-related death worldwide. However, limited research has focused on "female" cohorts, which have presented a higher incidence rate. In this study, the microarray data of lung cancer tissues derived from 54 female lung cancer patients, consisting of 43 nonsmokers and 11 smokers, were selected from GSE2109 dataset. A total of 249 differentially expressed genes (DEGs) including 102 up- and 147 down-regulated genes were identified and further analyzed for gene ontology (GO) terms and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment. By constructing protein-protein interaction (PPI) network and calculating key modules, 10 hub genes were screened out. The module analysis of the PPI network presented that the progression of female LCNS was significantly associated with immune response as chemokine activity and lipopolysaccharide response, and these biological processes (BP) might be mediated by chemokine signaling pathway and cytokine-cytokine receptor interaction. Then, survival analysis by Kaplan-Meier (K-M) Plotter online platform presented down-regulated gene colony stimulating factor 2 receptor beta common subunit (CSF2RB) of female LCNS might be involved in poor clinical outcome. Female LCNS with high expression of CSF2RB might be relevant with relative risk reduction of mortality, longer median survival time and higher 5-year survival rate, while female LCNS with low expression of CSF2RB might be implicated in a poor clinical outcome. In short, our results support CSF2RB to be a candidate survival predictor for female LCNS.


Assuntos
Neoplasias Pulmonares , Fumantes , Humanos , Mapas de Interação de Proteínas/genética , Biologia Computacional/métodos , Neoplasias Pulmonares/genética , Regulação Neoplásica da Expressão Gênica , Quimiocinas/genética , Perfilação da Expressão Gênica/métodos
17.
Mar Pollut Bull ; 193: 115209, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37364339

RESUMO

The coast of Laizhou Bay is plagued by a number of environmental issues, such as eutrophication, which are likely to worsen over the next few decades as a result of trends toward industrialization and urbanization. High nutrient levels in the Xiaoqing River are believed to be the main cause of Laizhou Bay becoming eutrophicated. Therefore, we conducted two cruises from the Xiaoqing River estuary to Laizhou Bay in August 2022 and December 2022, respectively, in the wet and dry periods to assess the potential impact of status of eutrophication due to human activities. The results showed that the concentration of DIN was higher than the quality standard for water (fi > 1) in both the wet season (August 2022) and the dry season (December 2022). DIN has major environmental impacts in Laizhou Bay. The eutrophication level index and organic pollution index have obvious spatial and temporal characteristics. In terms of time, the dry season is higher than the wet season. In space, Xiaoqing estuary is higher than Laizhou Bay. In the two surveys, DIN and DIP concentrations were significantly positively correlated, indicating that N and P pollution in the region had a common source and destination, and the spatial distribution was also similar. In addition, the current environmental conditions in the region are not ideal, reaching moderate and severe eutrophication levels, which proves that the ecosystem has the risk of aggravating degradation. As the Xiaoqing River is about to resume full navigation, human-related nutrient input (especially DIN) will continue to increase, and it is expected that the eutrophication risk in this area will increase in the next few years due to the increase in nutrient load.


Assuntos
Ecossistema , Rios , Humanos , Estuários , Baías , Monitoramento Ambiental/métodos , Eutrofização , China , Nitrogênio/análise
18.
Small ; 19(44): e2303757, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37381640

RESUMO

Covalent organic frameworks (COFs) are porous crystalline polymeric materials formed by the covalent bonding of organic units. The abundant organic units library gives the COFs species diversity, easily tuned pore channels, and pore sizes. In addition, the periodic arrangement of organic units endows COFs regular and highly connected pore channels, which has led to the rapid development of COFs in membrane separations. Continuous defect-free and high crystallinity of COF membranes is the key to their application in separations, which is the most important issue to be addressed in the research. This review article describes the linkage types of covalent bonds, synthesis methods, and pore size regulation strategies of COFs materials. Further, the preparation strategies of continuous COFs membranes are highlighted, including layer-by-layer (LBL) stacking, in situ growth, interfacial polymerization (IP), and solvent casting. The applications in separation fields of continuous COFs membranes are also discussed, including gas separation, water treatment, organic solvent nanofiltration, ion conduction, and energy battery membranes. Finally, the research results are summarized and the future prospect for the development of COFs membranes are outlined. More attention may be paid to the large-scale preparation of COFs membranes and the development of conductive COFs membranes in future research.

19.
J Texture Stud ; 54(4): 456-469, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37224845

RESUMO

To reproduce the tactile perception of multiple contacts on the human tongue surface, it is necessary to use a pressure measurement device with high spatial resolution. However, reducing the size of the array sensing unit and optimizing the lead arrangement still pose challenges. This article describes a deconvolution neural network (DNN) for improving the resolution of tongue surface tactile imaging, which alleviates this tradeoff between tactile sensing performance and hardware simplicity. The model can work without high-resolution tactile imaging data of tongue surface: First, in the compression test using artificial tongues, the tactile image matrix (7 × 7) with low resolution can be acquired by sensor array with a sparse electrode arrangement. Then, through finite element analysis modeling, combined with the distribution rule of additional stress on the two-dimensional plane, the pressure data around the existing detection points are calculated, further expanding the tactile image matrix data amount. Finally, the DNN, based on its efficient nonlinear reconstruction attributes, uses the low-resolution and high-resolution tactile imaging matrix generated by compression test and finite element simulation, respectively, to train, and outputs high-resolution tactile imaging information (13 × 13) closer to the tactile perception of the tongue surface. The results show that the overall accuracy of the tactile image matrix calculated by this model is above 88%. Then, we deduced the spatial difference graph of the resilience index of the three kinds of ham sausages through the high-resolution tactile imaging matrix.


Assuntos
Redes Neurais de Computação , Percepção do Tato , Humanos , Tato , Simulação por Computador , Língua
20.
Materials (Basel) ; 16(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37048975

RESUMO

In order to prepare nano-TbF3 coating with high quality on the surface of Nd-Fe-B magnets by electrophoretic deposition (EPD) more efficiently, Mg2+ and Cu2+ charging agents are introduced into the electrophoretic suspension and the influence on the electrophoretic deposition is systematically investigated. The results show that the addition of Mg2+ and Cu2+ charging agents can improve the electrophoretic deposition efficiency and coating adhesion of nano-TbF3 powders on sintered Nd-Fe-B magnets. The EPD efficiency increases by 116% with a relative content of Mg2+ as 3%, while it increases by 109% with a relative content of Cu2+ as 5%. Combining the Hamaker equation and diffusion electric double layer theory, the addition of Mg2+ and Cu2+ can change the zeta potential of charged particles, resulting in the improvement of EPD efficiency. The relative content of Mg2+ below 3% and Cu2+ below 5% can increase the thickness of the diffusion electric double layer, the excessive addition of a charging agent will compress the diffusion electric double layer, and thicker diffusion layer represents higher zeta potential. Furthermore, the addition of Mg2+ and Cu2+ charging agents greatly improves the coating adhesion, and the critical load for the cracking of the coating increases to 146.4 mN and 40.2 mN from 17.9 mN, respectively.

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