Nothing Special   »   [go: up one dir, main page]

You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled.
 
 
Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (1,630)

Search Parameters:
Keywords = mHealth applications

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
12 pages, 655 KiB  
Article
High-Sensitivity Electrical Admittance Sensor with Regression Analysis for Measuring Mixed Electrolyte Concentrations
by Chun-Chi Chen, Chih-Hung Hung, Han-Xiang Zhu and Ji-Zun Chen
Sensors 2024, 24(22), 7379; https://doi.org/10.3390/s24227379 - 19 Nov 2024
Abstract
Electrolyte balance is essential for the proper functioning of the body, and imbalances can lead to various health issues, some of which may be life-threatening. Therefore, measuring electrolyte concentrations is becoming increasingly important, particularly for athletes engaged in high-intensity and prolonged physical activity. [...] Read more.
Electrolyte balance is essential for the proper functioning of the body, and imbalances can lead to various health issues, some of which may be life-threatening. Therefore, measuring electrolyte concentrations is becoming increasingly important, particularly for athletes engaged in high-intensity and prolonged physical activity. In this project, we developed a highly sensitive sensing device capable of accurately and rapidly measuring electrolyte concentrations in mixed solutions, providing precise analysis of trace electrolyte levels. The sensor device requires no complex operational procedures and can quickly complete measurements, making it well-suited for point-of-care applications. Integration of regression models further enhances the device’s ability to estimate concentrations in mixed electrolyte solutions. The test results demonstrate that the device can detect subtle concentration variations, with a precision as low as 0.5 mM. This proposed sensing device offers a cost-effective and efficient solution for real-time monitoring of electrolyte levels in healthcare. Full article
(This article belongs to the Special Issue Bioimpedance Measurements and Microelectrodes)
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>Equivalent circuit model for an electrolyte sample. (<b>a</b>) The equivalent circuit consists of the polarization impedance of the electrodes, represented by <math display="inline"><semantics> <msub> <mi>R</mi> <mi>P</mi> </msub> </semantics></math> and <math display="inline"><semantics> <msub> <mi>C</mi> <mi>P</mi> </msub> </semantics></math>, along with the sample impedance, represented by <math display="inline"><semantics> <msub> <mi>R</mi> <mi>S</mi> </msub> </semantics></math> and <math display="inline"><semantics> <msub> <mi>C</mi> <mi>S</mi> </msub> </semantics></math>. (<b>b</b>) The simplified equivalent circuit consists of the equivalent admittance <math display="inline"><semantics> <msub> <mi>Y</mi> <mi>T</mi> </msub> </semantics></math>, represented by conductance <math display="inline"><semantics> <msub> <mi>G</mi> <mi>T</mi> </msub> </semantics></math> and capacitance <math display="inline"><semantics> <msub> <mi>C</mi> <mi>T</mi> </msub> </semantics></math>.</p>
Full article ">Figure 2
<p>The electrolyte sensing system. The sinusoidal oscillator generates a sinusoidal signal to test the samples on the sensor device. The testing signal response is then amplified by a comparator-based operational amplifier (op-amp) and converted into digital signals by an analog-to-digital converter (ADC) for precise and coherent detection.</p>
Full article ">Figure 3
<p>The electrode sensing device. (<b>a</b>) The sensor device comprises coplanar copper electrodes on the PCB, utilizing a working electrode and a reference electrode array for measurements. The PCB also incorporates corner holes to ensure precise positioning. (<b>b</b>) The cross-sectional diagram of the sensing device shows the sensing electrodes embedded within the copper foil layer, covered with a thin insulation layer (PSR-2000) on the PCB.</p>
Full article ">Figure 4
<p>The comparator−based operational amplifier. (<b>a</b>) The comparator-based op-amp circuit amplifies the difference in signal response between the target admittance <math display="inline"><semantics> <mrow> <msub> <mi>Y</mi> <mn>0</mn> </msub> <mo>+</mo> <mo>Δ</mo> <mi>Y</mi> </mrow> </semantics></math> and the reference admittance <math display="inline"><semantics> <msub> <mi>Y</mi> <mn>1</mn> </msub> </semantics></math>. (<b>b</b>) The circuit of the signal generator produces two-phase driving signals with a 180° phase difference. The inverting op-amp can control the output amplitude by adjusting the variable resistor <math display="inline"><semantics> <msub> <mi>R</mi> <mn>1</mn> </msub> </semantics></math>. The Phase Shift (PS) networks can adjust the phase to synchronize the signal and minimize the phase difference by utilizing the variable resistance <math display="inline"><semantics> <msub> <mi>R</mi> <mn>2</mn> </msub> </semantics></math>.</p>
Full article ">Figure 4 Cont.
<p>The comparator−based operational amplifier. (<b>a</b>) The comparator-based op-amp circuit amplifies the difference in signal response between the target admittance <math display="inline"><semantics> <mrow> <msub> <mi>Y</mi> <mn>0</mn> </msub> <mo>+</mo> <mo>Δ</mo> <mi>Y</mi> </mrow> </semantics></math> and the reference admittance <math display="inline"><semantics> <msub> <mi>Y</mi> <mn>1</mn> </msub> </semantics></math>. (<b>b</b>) The circuit of the signal generator produces two-phase driving signals with a 180° phase difference. The inverting op-amp can control the output amplitude by adjusting the variable resistor <math display="inline"><semantics> <msub> <mi>R</mi> <mn>1</mn> </msub> </semantics></math>. The Phase Shift (PS) networks can adjust the phase to synchronize the signal and minimize the phase difference by utilizing the variable resistance <math display="inline"><semantics> <msub> <mi>R</mi> <mn>2</mn> </msub> </semantics></math>.</p>
Full article ">Figure 5
<p>The admittance responses for deionized water and diluted NaCl solutions across concentrations ranging from <math display="inline"><semantics> <mrow> <mn>0.5</mn> </mrow> </semantics></math> to <math display="inline"><semantics> <mrow> <mn>4</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> mM are presented, with the blue line measured at <math display="inline"><semantics> <mrow> <mn>5</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz and the red line measured at <math display="inline"><semantics> <mrow> <mn>10</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz. The responses are normalized using deionized water as the reference, and each error bar shows the standard deviation of the measurements.</p>
Full article ">Figure 6
<p>The admittance responses for deionized water and diluted KCl solutions across concentrations ranging from <math display="inline"><semantics> <mrow> <mn>0.5</mn> </mrow> </semantics></math> to <math display="inline"><semantics> <mrow> <mn>4</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> mM are presented, with the blue line measured at <math display="inline"><semantics> <mrow> <mn>5</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz and the red line measured at <math display="inline"><semantics> <mrow> <mn>10</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz. The responses are normalized using deionized water as the reference, and each error bar shows the standard deviation of the measurements.</p>
Full article ">Figure 7
<p>The admittance measured at <math display="inline"><semantics> <mrow> <mn>5</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz responses for deionized water and mixed NaCl and KCl solutions across concentrations ranging from <math display="inline"><semantics> <mrow> <mn>0.5</mn> </mrow> </semantics></math> to <math display="inline"><semantics> <mrow> <mn>4</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> mM. The (<b>a</b>) quadrature response and (<b>b</b>) in-phase response are normalized using deionized water as the reference solution. Each error bar indicates the standard deviation of the measurements.</p>
Full article ">Figure 7 Cont.
<p>The admittance measured at <math display="inline"><semantics> <mrow> <mn>5</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz responses for deionized water and mixed NaCl and KCl solutions across concentrations ranging from <math display="inline"><semantics> <mrow> <mn>0.5</mn> </mrow> </semantics></math> to <math display="inline"><semantics> <mrow> <mn>4</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> mM. The (<b>a</b>) quadrature response and (<b>b</b>) in-phase response are normalized using deionized water as the reference solution. Each error bar indicates the standard deviation of the measurements.</p>
Full article ">Figure 8
<p>The admittance measured at <math display="inline"><semantics> <mrow> <mn>10</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> kHz responses for deionized water and mixed NaCl and KCl solutions across concentrations ranging from <math display="inline"><semantics> <mrow> <mn>0.5</mn> </mrow> </semantics></math> to <math display="inline"><semantics> <mrow> <mn>4</mn> <mspace width="1.66656pt"/> </mrow> </semantics></math> mM. The (<b>a</b>) quadrature response and (<b>b</b>) in-phase response are normalized using deionized water as the reference solution. Each error bar indicates the standard deviation of the measurements.</p>
Full article ">
25 pages, 3157 KiB  
Article
Breaking Barriers: The Design and Development of an Assistive Technology Web App for Older Latinos with Disabilities in Daily Activities
by Elsa M. Orellano-Colón, Adriana I. Ramos-Marichal, Valeria R. González-Crespo, Bianca N. Zeballos-Hernández, Kenneth N. Ruiz-Márquez, Abiel Roche-Lima, Joan M. Adorno-Mercado, Norman A. Laborde-Torres, Joshua G. Berríos-Llopart, Angely M. Cruz-Ramos, Dana V. Montenegro, Carmen E. Lamoutte, Natasha D. Rosa-Casilla and David E. Meléndez-Berrios
Technologies 2024, 12(11), 232; https://doi.org/10.3390/technologies12110232 - 19 Nov 2024
Abstract
Latinos are among the populations who are the least likely to use assistive technology (AT) despite being a population with a high prevalence of functional disabilities (FDs). We aimed to create and test the usability of an AT web app for independent-living older [...] Read more.
Latinos are among the populations who are the least likely to use assistive technology (AT) despite being a population with a high prevalence of functional disabilities (FDs). We aimed to create and test the usability of an AT web app for independent-living older adults with FDs. In Phase I, we created the web app’s content guided by the Optimized Honeycomb Model and considered the AT needs and FDs of older Puerto Ricans found in our previous studies. In Phase II, we design the web application by adopting a Lean UX process and design heuristics for older adults. In Phase III, we conducted usability testing using focus groups and individual interviews with 14 older adults, interpreted through a directed content analysis. The Mi Guía de Asistencia Tecnológica (MGAT) was developed with ninety-four AT devices in eight areas of daily activities. The MGAT provides comprehensive information on AT, including photos and videos of older adults using AT. Participants reported that the MGAT was usable, accessible, credible, desirable, useful, and valuable in increasing their knowledge of AT. These findings are a foundation for developing efficient AT information strategies using such technology as a first step to improving AT adoption among older adults. Full article
Show Figures

Figure 1

Figure 1
<p>Content of the AT guide web app. The graphic lists the categories and subcategories of the daily activities included in the AT guide web app.</p>
Full article ">Figure 2
<p>Screens of the web app. Screenshots depicting application navigation from the introductory screen to the home page, Categories of Activities Screen, Subcategories of Activities Screen, AT Device Options Screen, and the Final AT Device Screen.</p>
Full article ">Figure 3
<p>User experience themes and subthemes. The graphic depicts the user experience mapped onto the deductive themes and inductive subthemes based on the Optimized Honeycomb Model.</p>
Full article ">Figure 4
<p>Participants experience within the ‘Use’ dimension of the Karagianni Optimized Honeycomb Model. The graphic depicts the user experience mapped onto the deductive ‘Use’ facets of ‘Findable’, ‘Accessible’, and ‘Usable’ and their corresponding inductive subthemes.</p>
Full article ">Figure 5
<p>Participants experience within the ‘Think’ dimension of Karagianni’s Optimized Honeycomb Model. The graphic depicts the user experience mapped onto the deductive ‘Think’ facets of ‘Desirable’ and ‘Credible’ and their corresponding inductive subthemes.</p>
Full article ">Figure 6
<p>Participants’ experience within the ‘Feel’ dimension of Karagianni’s Optimized Honeycomb Model. The graphic depicts the users’ experience mapped onto the deductive ‘Feel’ facets of ‘Useful’ and ‘Valuable’ and their corresponding inductive subthemes.</p>
Full article ">
21 pages, 7206 KiB  
Article
Remote Sensing Fine Estimation Model of PM2.5 Concentration Based on Improved Long Short-Term Memory Network: A Case Study on Beijing–Tianjin–Hebei Urban Agglomeration in China
by Yiye Ji, Yanjun Wang, Cheng Wang, Xuchao Tang and Mengru Song
Remote Sens. 2024, 16(22), 4306; https://doi.org/10.3390/rs16224306 - 19 Nov 2024
Viewed by 136
Abstract
The accurate prediction of PM2.5 concentration across extensive temporal and spatial scales is essential for air pollution control and safeguarding public health. To address the challenges of the uneven coverage and limited number of traditional PM2.5 ground monitoring networks, the low [...] Read more.
The accurate prediction of PM2.5 concentration across extensive temporal and spatial scales is essential for air pollution control and safeguarding public health. To address the challenges of the uneven coverage and limited number of traditional PM2.5 ground monitoring networks, the low inversion accuracy of PM2.5 concentration, and the incomplete understanding of its spatiotemporal dynamics, this study proposes a refined PM2.5 concentration estimation model, Bi-LSTM-SA, integrating multi-source remote sensing data. First, utilizing multi-source remote sensing data, such as MODIS aerosol optical depth (AOD) products, meteorological data, and PM2.5 monitoring sites, AERONET AOD was used to validate the accuracy of the MODIS AOD data. Variables including temperature (TEMP), relative humidity (RH), surface pressure (SP), wind speed (WS), and total precipitation (PRE) were selected, followed by the application of the variance inflation factor (VIF) and Pearson’s correlation coefficient (R) for variable screening. Second, to effectively capture temporal dependencies and emphasize key features, an improved Long Short-Term Memory Network (LSTM) model, Bi-LSTM-SA, was constructed by combining a bidirectional LSTM (Bi-LSTM) model with a self-adaptive attention mechanism (SA). This model was evaluated through ablation and comparative experiments using three cross-validation methods: sample-based, temporal, and spatial. The effectiveness of this method was demonstrated on Beijing–Tianjin–Hebei urban agglomeration, achieving a coefficient of determination (R2) of 0.89, root mean squared error (RMSE) of 12.76 μg/m3, and mean absolute error (MAE) of 8.27 μg/m3. Finally, this model was applied to predict PM2.5 concentration on Beijing–Tianjin–Hebei urban agglomeration in 2023, revealing the characteristics of its spatiotemporal evolution. Additionally, the results indicated that this model performs exceptionally well in hourly PM2.5 concentration forecasting and can be used for PM2.5 concentration hourly prediction tasks. This study provides technical support for the large-scale, accurate remote sensing inversion of PM2.5 concentration and offers fundamental insights for regional atmospheric environmental protection. Full article
Show Figures

Figure 1

Figure 1
<p>Research flowchart in this study.</p>
Full article ">Figure 2
<p>The distribution of PM<sub>2.5</sub> monitoring stations on Beijing–Tianjin–Hebei urban agglomeration.</p>
Full article ">Figure 3
<p>Verification results of MODIS AOD and AERONET AOD. Among them, N represents the number of matches.</p>
Full article ">Figure 4
<p>Self-adaptive attention mechanism processing flow.</p>
Full article ">Figure 5
<p>Bi-LSTM-SA network structure.</p>
Full article ">Figure 6
<p>Density scatter plot of the ablation experiment results. Among them, the units of RMSE and MAE are μg/m<sup>3</sup>. In this figure, the three rows indicate the fitting results under sample-based, spatial, and temporal cross-validation (CV), while the four columns indicate the fitting results of basic LSTM, Bi-LSTM, LSTM-SA and Bi-LSTM-SA models, respectively. The solid black line in the figure represents the fitted straight line of y = x, and the solid red line represents the best fit line of the linear regression.</p>
Full article ">Figure 7
<p>The density scatter plot of the comparative experiment results. Among them, the units of RMSE and MAE are μg/m<sup>3</sup>. In this figure, the three rows indicate the fitting results under sample-based, spatial and temporal cross-validation (CV), while the four columns indicate the fitting results of Transformer, CNN, RF and Bi-LSTM-SA models, respectively. The solid black line in the figure represents the fitted straight line of y = x, and the solid red line represents the best fit line of the linear regression.</p>
Full article ">Figure 8
<p>Fit comparison. (<b>a</b>): Fit result of Bi-LSTM-SA model predictions vs. observed values; (<b>b</b>): fit result of CHAP PM<sub>2.5</sub> data vs. observed values; N: the number of valid data samples. The units of RMSE and MAE are μg/m<sup>3</sup>. The solid black line in the figure represents the fitted straight line of y = x, and the solid red line represents the best fit line of the linear regression.</p>
Full article ">Figure 9
<p>The spatio-temporal pattern of the monthly average PM<sub>2.5</sub> concentrations in the Beijing–Tianjin–Hebei urban agglomeration for 2023.</p>
Full article ">Figure 10
<p>The comparison of the five models’ PM<sub>2.5</sub> concentration forecasting performance across different time windows within the next 72 h. The figure represents the R<sup>2</sup>, RMSE and MAE between the predicted and observed values for each station under the same test set.</p>
Full article ">Figure 11
<p>PM<sub>2.5</sub> prediction trends versus actual trends at different stations and times, (<b>a</b>–<b>d</b>) representing different stations.</p>
Full article ">
18 pages, 897 KiB  
Article
Valorization of Bioactive Compounds from Lingonberry Pomace and Grape Pomace with Antidiabetic Potential
by Elena Neagu, Gabriela Paun, Camelia Albu and Gabriel Lucian Radu
Molecules 2024, 29(22), 5443; https://doi.org/10.3390/molecules29225443 (registering DOI) - 18 Nov 2024
Viewed by 225
Abstract
In recent years, increased attention has been paid to the recovery of bioactive compounds from waste and by-products resulting from the agro-industrial sector and their valorization into new products, which can be used in the health, food, or agricultural industry, as innovative and [...] Read more.
In recent years, increased attention has been paid to the recovery of bioactive compounds from waste and by-products resulting from the agro-industrial sector and their valorization into new products, which can be used in the health, food, or agricultural industry, as innovative and sustainable approaches to waste management. In this work, two of these by-products resulting from the fruit-processing industry were used for the recovery of bioactive compounds (polyphenols), namely lingonberry pomace (Vaccinium vitis-idaea) and grape pomace (Vitis vinifera). Two green extraction techniques were employed to obtain hydroalcoholic extracts (solvent: 50% EtOH, 10% mass): ultrasound-assisted extraction (UAE) and accelerated solvent extraction (ASE). The extracts were subjected to micro- and ultrafiltration processes, and further analyzed to determine the bioactive compound content through spectrophotometric (UV-Vis) and chromatographic (HPLC-PDA) methods. Additionally, the extracts exhibited significant enzyme inhibition, particularly against α-amylase and β-glucosidase, suggesting potential anti-diabetic properties. The extracts characteristics, polyphenolic content, antioxidant capacity and enzyme inhibitory ability, were statistically compared, and significant differences were found between the two extraction methods. The grape pomace concentrated extracts showed a pronounced inhibitory activity on both analyzed enzymes compared to the lingonberry pomace concentrated extracts, closer to the standard used; e.g., IC50 α-amylase = 0.30 ± 0.01 µg/mL (IC50 acarbose = 0.3 ± 0.01 µg/mL), IC50 α-glucosidase = 0.60 ± 0.01 µg/mL (IC50 acarbose = 0.57 ± 0.02 µg/mL). These findings highlight the potential of agro-industrial residues as bioactive compound resources, with their valorization through application in food, nutraceutical, or pharmaceutical industries therefore contributing to the sustainable development and promotion of circular economy principles with the recovery of valuable inputs from plant by-products. Full article
Show Figures

Figure 1

Figure 1
<p>Chromatograms for lingonberry residue’s concentrated extract, ASE method ((<b>A</b>)—the phenolic acids and flavonoids chromatogram at 327 nm, (<b>B</b>)—the anthocyanidins and anthocyanins chromatogram at 528 nm).</p>
Full article ">Figure 2
<p>Chromatograms for grape pomace extract, ASE concentrate ((<b>A</b>)—phenolic acids and flavonoids chromatogram at 327 nm, (<b>B</b>)—anthocyanidins and anthocyanins chromatogram at 528 nm).</p>
Full article ">
18 pages, 1522 KiB  
Article
Novel Liposome–Gel Formulations Containing a Next Generation Postbiotic: Characterization, Rheological, Stability, Release Kinetic, and In Vitro Antimicrobial Activity Studies
by Halise Betül Gökçe and İsmail Aslan
Gels 2024, 10(11), 746; https://doi.org/10.3390/gels10110746 - 15 Nov 2024
Viewed by 202
Abstract
In recent years, in addition to the positive effects of probiotics and prebiotics on health, increasing research has shown that postbiotics also have significant potential in the health field. Postbiotics are bioactive components produced by probiotic bacteria during fermentation and may exhibit antimicrobial [...] Read more.
In recent years, in addition to the positive effects of probiotics and prebiotics on health, increasing research has shown that postbiotics also have significant potential in the health field. Postbiotics are bioactive components produced by probiotic bacteria during fermentation and may exhibit antimicrobial activity. This study investigated the antimicrobial effects of liposomal postbiotics formulated in gel. Various postbiotic-containing liposomal systems have been developed and optimized to prepare formulations. Optimized liposomes and liposomal postbiotic-containing gel forms were examined in terms of particle size, polydispersity index, zeta potential, structural properties, encapsulation efficiency, permeability, release profiles, and stability. Finally, the antimicrobial activities of the postbiotics and the optimum gel formulation LG1 were evaluated on Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Enterococcus hirae, and Candida albicans strains using disk diffusion and microdilution methods. The optimum liposome formulation L1 was determined to have a particle size of 185.32 ± 0.80 nm, a polydispersity index of 0.206 ± 0.012, a zeta potential of 35.0 ± 0.5 mV, and an encapsulation efficiency of 17.52%. Its permeability was determined as 51.52% at the end of 6 h. In vitro release studies showed that the drug release profile was in accordance with first-order kinetics and suitable for controlled release. The findings show that formulated postbiotics have similar antimicrobial activity to free postbiotics. These results suggest that liposomal gel formulations support the antimicrobial effects of postbiotics while providing advantages of use. In conclusion, the findings contribute to a better understanding of the antimicrobial potential of postbiotics and lipogelosomal postbiotics and optimize their use in pharmaceutical applications. Full article
15 pages, 4260 KiB  
Article
Microwave-Assisted Synthesis of N, S Co-Doped Carbon Quantum Dots for Fluorescent Sensing of Fe(III) and Hydroquinone in Water and Cell Imaging
by Zhaochuan Yu, Chao Deng, Wenhui Ma, Yuqian Liu, Chao Liu, Tingwei Zhang and Huining Xiao
Nanomaterials 2024, 14(22), 1827; https://doi.org/10.3390/nano14221827 - 14 Nov 2024
Viewed by 503
Abstract
The detection of heavy metal ions and organic pollutants from water sources remains critical challenges due to their detrimental effects on human health and the environment. Herein, a nitrogen and sulfur co-doped carbon quantum dot (NS-CQDs) fluorescent sensor was developed using a microwave-assisted [...] Read more.
The detection of heavy metal ions and organic pollutants from water sources remains critical challenges due to their detrimental effects on human health and the environment. Herein, a nitrogen and sulfur co-doped carbon quantum dot (NS-CQDs) fluorescent sensor was developed using a microwave-assisted carbonization method for the detection of Fe3+ ions and hydroquinone (HQ) in aqueous solutions. NS-CQDs exhibit excellent optical properties, enabling sensitive detection of Fe3+ and HQ, with detection limits as low as 3.40 and 0.96 μM. Notably, with the alternating introduction of Fe3+ and HQ, NS-CQDs exhibit significant fluorescence (FL) quenching and recovery properties. Based on this property, a reliable “on-off-on” detection mechanism was established, enabling continuous and reversible detection of Fe3+ and HQ. Furthermore, the low cytotoxicity of NS-CQDs was confirmed through successful imaging of HeLa cells, indicating their potential for real-time intracellular detection of Fe3+ and HQ. This work not only provides a green and rapid synthesis strategy for CQDs but also highlights their versatility as fluorescent probes for environmental monitoring and bioimaging applications. Full article
(This article belongs to the Special Issue Nanomaterials in Electrochemical Electrode and Electrochemical Sensor)
Show Figures

Figure 1

Figure 1
<p>Synthesis and characterization of NS-CQDs. (<b>a</b>) HRTEM image of NS-CQDs (the inset shows its lattice fringes). (<b>b</b>) Diameter distribution analysis, (<b>c</b>) XRD, (<b>d</b>) AFM image, (<b>e</b>) height distribution analysis, and (<b>f</b>) Raman spectroscopy of NS-CQDs.</p>
Full article ">Figure 2
<p>Chemical composition analysis of NS-CQDs. (<b>a</b>) FTIR and (<b>b</b>) XPS spectra of NS-CQDs. (<b>c</b>–<b>f</b>) High-resolution XPS of C 1s, N 1s, S 2p, and O 1s, respectively.</p>
Full article ">Figure 3
<p>Evaluation of FL properties of NS-MQDs. (<b>a</b>) UV-vis absorption spectra and FL excitation (Ex) and FL emission (Em) spectra of NS-MQDs in aqueous solution. (<b>b</b>) FL emission spectra of NS-MQDs at different excitation wavelengths (320–480 nm).</p>
Full article ">Figure 4
<p>“On-off-on” detection performance of NS-CQDs for Fe<sup>3+</sup> and HQ. (<b>a</b>) The concentration-dependent emission spectra of NS-CQDs at different concentrations of Fe<sup>3+</sup> (0–833.3 μM). (<b>b</b>) Stern-Volmer plot of F/F<sub>0</sub> versus Fe<sup>3+</sup> concentration for NS-CQDs. (<b>c</b>) FL intensity change profiles of NS-CQDs in the presence of potential competing ions (green) and Fe<sup>3+</sup> upon addition of competing anions (3-fold excess, purple) in DI water. (<b>d</b>) The concentration-dependent emission spectra of (NS-CQDs+Fe<sup>3+</sup>) for different concentrations of HQ (0–1333.3 μM). (<b>e</b>) Stern-Volmer plot of F/F<sub>0</sub> versus HQ concentration for (NS-CQDs+Fe<sup>3+</sup>). (<b>f</b>) FL intensity change profiles of NS-CQDs in the presence of potential competing ions (green) and HQ upon addition of competing anions (3-fold excess, purple) in DI water.</p>
Full article ">Figure 5
<p>Fluorescence “on-off-on” principle of NS-CQDs. (<b>a</b>) UV-vis absorption spectrum and (<b>b</b>) FL decay curves of NS-CQDs before and after the addition of Fe<sup>3+</sup>. (<b>c</b>) FL spectrum of NS-CQDs, NS-CQDs+HQ, NS-CQDs+Fe<sup>3+</sup>, NS-CQDs Fe<sup>2+</sup>, and NS-CQDs+Fe<sup>3+</sup>+HQ. (<b>d</b>) Schematic of the proposed “on-off-on” mechanism for the detection of Fe<sup>3+</sup> and HQ using NS-CQDs.</p>
Full article ">Figure 6
<p>Confocal FL images of living HeLa cells. The images after incubating NS-CQDs at 37 °C for 4 h are as follows: (<b>a</b>) bright field, (<b>d</b>) FL, and (<b>g</b>) merged image. The images of HeLa cells stained with NS-CQDs after treatment with Fe<sup>3+</sup> (300 μM) for 4 h are: (<b>b</b>) bright field, (<b>e</b>) FL, and (<b>h</b>) merged image. The images of HeLa cells stained with NS-CQDs after treatment with Fe<sup>3+</sup> (300 μM) followed by HQ (300 μM) for 4 h are: (<b>c</b>) bright field, (<b>f</b>) FL, and (<b>i</b>) merged image.</p>
Full article ">Scheme 1
<p>Schematic of the fabrication of co-doped NS-CQDs and its applications.</p>
Full article ">
30 pages, 3795 KiB  
Article
Isolation and Characterization of Infection of Four New Bacteriophages Infecting a Vibrio parahaemolyticus Strain
by João Duarte, David Trindade, Vanessa Oliveira, Newton C. M. Gomes, Ricardo Calado, Carla Pereira and Adelaide Almeida
Antibiotics 2024, 13(11), 1086; https://doi.org/10.3390/antibiotics13111086 - 14 Nov 2024
Viewed by 454
Abstract
Bacteria from genus Vibrio continue to be one of the most common threats to aquaculture sustainability. Vibrio spp. have been associated with infectious outbreaks in fish, shrimp, bivalves and even algae farms worldwide. Moreover, several Vibrio spp. are also pathogens that impact human [...] Read more.
Bacteria from genus Vibrio continue to be one of the most common threats to aquaculture sustainability. Vibrio spp. have been associated with infectious outbreaks in fish, shrimp, bivalves and even algae farms worldwide. Moreover, several Vibrio spp. are also pathogens that impact human health and are a threat to public health when transferred to consumers through contaminated seafood products. The use of bacteriophages is an evolving technology that could be applied in the treatment of Vibrio spp. either to protect aquaculture farms or to decontaminate seafood, namely bivalves during their depuration. In the present study, bacteriophages vB_VpS_LMAVpS1 (S1) vB_VpS_LMAVpVPP (VPP), vB_VpS_LMAVpSH (SH) and vB_VpS_LMAVpH (H) infecting V. parahaemolyticus were isolated and characterized. All phages presented fast adsorption rates and were able to control V. parahaemolyticus at all multiplicity of infections (MOIs) tested (MOI of 1, 10 and 100), with reductions of more than 4 log CFU/mL being recorded, but only in the presence of divalent cation calcium. The rate of emergence of phage-resistant mutants was very low (1.8 × 10−6 to 3.1 × 10−6). Bacterial phage resistance was not permanent and led to a loss of bacterial fitness. All four phages presented with lysins encoded in their genomes. The results presented provide valuable insights for future studies in the application of these bacteriophages in different scenarios to control, decontaminate or treat bacterial infections or contaminations of V. parahaemolyticus. Full article
(This article belongs to the Section Bacteriophages)
Show Figures

Figure 1

Figure 1
<p>Phage virion morphology (<b>right</b>) and plaque morphology (<b>left</b>) of the four isolated phages.</p>
Full article ">Figure 2
<p>Proksee representation of the four phages isolated in this study. The genome of the SH phage was used as the reference for comparison with phages S1, VPP and H. The final circle with arrow-headed bands represents the coding DNA sequences (CDSs) of the SH phage color coded according to the functional category of the predicted gene in the direction of the transcription. The innermost ring represents the genome GC skew (green/pink) followed by GC content (black). The labels show the predicted functions of the functional CDS, color-coded by the PHROG category. The analysis was carried out on a PROKSEE Server that uses BLAST analysis to illustrate conserved and missing genomic sequences (accessed on 6 September 2024: <a href="https://proksee.ca/projects/new" target="_blank">https://proksee.ca/projects/new</a>).</p>
Full article ">Figure 3
<p>Phage adsorption curve. Samples were collected every 2 min. Three assays were performed for each phage. The results are expressed as the mean of three independent assays.</p>
Full article ">Figure 4
<p>Phage SH concentration after 0 (left column) and 6 h (right column) of incubation in the presence of bacteria. PBS—phage inoculated in PBS without the presence of bacteria; TSB—phage inoculated in TSB in the presence of bacteria; TSB + Mg—phage inoculated in the presence of bacteria in media supplemented with magnesium; TSB + Ca—phage inoculated in the presence of bacteria in media supplemented with calcium; TSB + Mg + Ca—phage inoculated in the presence of bacteria in media supplemented with magnesium and calcium. All groups were inoculated with bacteria to a final concentration of 10<sup>5</sup> CFU/mL and phage to a final titre of 10<sup>4</sup> PFU/mL. The results are expressed as the mean of three assays.</p>
Full article ">Figure 5
<p>Bacterial inactivation curves by Phage SH in medium supplemented with different concentrations of calcium. All groups were inoculated with the same concentrations of phage and bacteria. Bacterial control (BC)—bacteria inoculated without the presence of phages; 0.5 mM Ca—phage and bacteria in media supplemented with 0.5 mM of calcium; 1 mM Ca—phage and bacteria in media supplemented with 1 mM of calcium; 10 mM Ca—phage and bacteria in media supplemented with 10 mM of calcium. The results are expressed as the mean of three independent assays.</p>
Full article ">Figure 6
<p>Bacterial inactivation curves at different MOIs. Bacterial control—bacteria incubated in the absence of phages. S1, VP, SH and H represent the bacterial inactivation curves in the presence of the respective phage at an MOI of 1 (<b>top</b>), 10 (<b>middle</b>) and 100 (<b>bottom</b>). The results are expressed as the mean of three independent assays.</p>
Full article ">Figure 7
<p>Phage virion production and phage control during incubation with bacteria. Three different MOIs were evaluated: 1 (Phages_M1 (<b>top</b>)), 10 (Phages_M10 (<b>middle</b>)) and 100 (Phages_M100 (<b>bottom</b>)). S1, VP, SH and H represent the phage groups incubated in the presence of bacteria. CS1, CVP, CSH and CH represent the phage control groups incubated in the same conditions but without any host present. The results are expressed as the mean of three independent assays.</p>
Full article ">Figure 7 Cont.
<p>Phage virion production and phage control during incubation with bacteria. Three different MOIs were evaluated: 1 (Phages_M1 (<b>top</b>)), 10 (Phages_M10 (<b>middle</b>)) and 100 (Phages_M100 (<b>bottom</b>)). S1, VP, SH and H represent the phage groups incubated in the presence of bacteria. CS1, CVP, CSH and CH represent the phage control groups incubated in the same conditions but without any host present. The results are expressed as the mean of three independent assays.</p>
Full article ">Figure 8
<p>Growth curve of phage-resistant bacterial mutants and sensitive bacteria during 24 h using optical density readings at 600 nm.</p>
Full article ">Figure A1
<p>Inactivation curves of the four phages in standard media and in media supplemented with calcium to a final concentration of 1mM. BC—Bacterial control: bacteria grown in TSB supplemented with calcium and in the absence of any phages. S1, VP, SH and H: bacteria inoculated in the presence of the specific phages in media supplemented with calcium to a final concentration of 1 mM. S1, VP, SH and H N/Ca: bacteria inoculated in the presence of the specific phages in standard media with no calcium added.</p>
Full article ">
15 pages, 812 KiB  
Article
Effectiveness of a Complementary Telehealth Education Program as a Preventive Treatment for Chronic Migraine: A Randomized Pilot Study
by Paula Cordova-Alegre, Pablo Herrero, Sonia Santos-Lasaosa, Maria Pilar Navarro-Perez, Beatriz Carpallo-Porcar, Sandra Calvo and Carolina Jimenez-Sanchez
J. Clin. Med. 2024, 13(22), 6825; https://doi.org/10.3390/jcm13226825 - 13 Nov 2024
Viewed by 681
Abstract
Background/Objectives: Chronic migraine (CM) is a neurological disorder that causes significant disability, loss of productivity, and economic burden. Preventive treatments, including pharmacological and educational interventions, are crucial for managing CM effectively. The aim of this study was to analyze whether adding a therapeutic [...] Read more.
Background/Objectives: Chronic migraine (CM) is a neurological disorder that causes significant disability, loss of productivity, and economic burden. Preventive treatments, including pharmacological and educational interventions, are crucial for managing CM effectively. The aim of this study was to analyze whether adding a therapeutic telehealth education program (TTEP) to pharmacological treatment achieved a greater reduction in the number of headache days experienced by patients with CM. Methods: A randomized, double-blind, controlled pilot study with two parallel groups was performed. Patients with a diagnosis of CM and who were being treated with Botulinum Toxin were randomly assigned to either the EG (therapeutic education program about the neuroscience of pain, migraine, pain strategies, sleep habits, exercise, nutrition, postural habits, and relaxation strategies) or CG (general health recommendations with no specific content about migraine). The intervention lasted a total of eight weeks and was delivered via a telehealth application (APP). Headache frequency, migraine frequency, pain intensity, headache impact, allodynia, fear of movement, pain catastrophizing, chronic pain self-efficacy, anxiety and depression, sleep quality, and sedentary lifestyle were measured at baseline (M0), one month after the intervention started (M1), at the end of the intervention (M2), and one month after the intervention was completed for follow-up (M3). Results: In total, 48 patients participated. There were differences between the groups in the following outcomes in favor of EG for headache frequency at the one-month follow-up (p = 0.03; d = 0.681); chronic pain self-efficacy at post-treatment (p = 0.007; d = 0.885) and at the one-month follow-up (p < 0.001; d = 0.998); and sleep quality at post-treatment (p = 0.013; d = 0.786) and at the one-month follow-up (p < 0.001; d = 1.086). No differences existed between the groups for the other outcomes examined (p < 0.05). Conclusions: The use of TTEP reduced the number of headache days, improved sleep quality, and increased self-efficacy in managing pain. This pilot study suggests that the addition of a specialized TTPE to pharmacological treatments may be more effective than a general health recommendation program for migraine. Full article
(This article belongs to the Section Clinical Neurology)
Show Figures

Figure 1

Figure 1
<p>CONSORT flow diagram.</p>
Full article ">
15 pages, 2507 KiB  
Article
Alkali Ion-Accelerated Gelation of MXene-Based Conductive Hydrogel for Flexible Sensing and Machine Learning-Assisted Recognition
by Weidan Na, Chao Xu, Lei An, Changjin Ou, Fan Gao, Guoyin Zhu and Yizhou Zhang
Gels 2024, 10(11), 720; https://doi.org/10.3390/gels10110720 - 7 Nov 2024
Viewed by 527
Abstract
Conductive hydrogels are promising active materials for wearable flexible electronics, yet it is still challenging to fabricate conductive hydrogels with good environmental stability and electrical properties. In this work, a conductive MXene/LiCl/poly(sulfobetaine methacrylate) hydrogel system was successfully prepared with an impressive conductivity of [...] Read more.
Conductive hydrogels are promising active materials for wearable flexible electronics, yet it is still challenging to fabricate conductive hydrogels with good environmental stability and electrical properties. In this work, a conductive MXene/LiCl/poly(sulfobetaine methacrylate) hydrogel system was successfully prepared with an impressive conductivity of 12.2 S/m. Interestingly, the synergistic effect of MXene and a lithium bond can significantly accelerate the polymerization process, forming the conductive hydrogel within 1 min. In addition, adding LiCl to the hydrogel not only significantly increases its water retention ability, but also enhances its conductivity, both of which are important for practical applications. The flexible strain sensors based on the as-prepared hydrogel have demonstrated excellent monitoring ability for human joint motion, pulse, and electromyographic signals. More importantly, based on machine learning image recognition technology, the handwritten letter recognition system displayed a high accuracy rate of 93.5%. This work demonstrates the excellent comprehensive performance of MXene-based hydrogels in health monitoring and image recognition and shows potential applications in human–machine interfaces and artificial intelligence. Full article
(This article belongs to the Special Issue Gels for Flexible Electronics and Energy Devices (2nd Edition))
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>(<b>a</b>) Schematic diagram of preparation conductive PSBMA-LM hydrogel. (<b>b</b>,<b>c</b>) Tensile stress–strain curves and toughness and elastic modulus of PSBMA hydrogel with different PEGDA contents. (<b>d</b>,<b>e</b>) Tensile stress–strain curves and toughness and elastic modulus of PSBMA-L hydrogel with different LiCl contents. (<b>f</b>,<b>g</b>) Tensile stress–strain curves and toughness and elastic modulus of PSBMA-LM hydrogel with different MXene contents. SEM image of freeze-dried PSBMA hydrogel (<b>h</b>), PSBMA-L hydrogel (<b>i</b>), and PSBMA-LM hydrogel (<b>j</b>).</p>
Full article ">Figure 2
<p>(<b>a</b>) <sup>1</sup>H NMR spectra of PSBMA hydrogel. (<b>b</b>) <sup>1</sup>H NMR spectra of PSBMA-L hydrogel. (<b>c</b>) XPS spectra of Ti 2p spectra of MXene. (<b>d</b>) Rheological behavior test of PSBMA, PSBMA-L, and PSBMA-LM hydrogels. (<b>e</b>,<b>f</b>) FTIR spectra of freeze-dried PSBMA-M, PSBMA-LM, PSBMA-NM, and PSBMA-KM hydrogels. (<b>g</b>) Schematic of the lithium bond in PSBMA-LM hydrogel, the colored balls represent different atoms (red: oxygen atom; grey: carbon atom; blue: nitrogen atom; white: hydrogen atom).</p>
Full article ">Figure 3
<p>(<b>a</b>,<b>b</b>) The stress–strain curves of PSBMA-L and PSBMA-LM hydrogels within seven days at 25 °C. (<b>c</b>,<b>d</b>) The stress–strain curves of PSBMA-L and PSBMA-LM hydrogels within seven days at 50 °C. (<b>e</b>) Conductivity of PSBMA, PSBMA-L, and PSBMA-LM hydrogels. (<b>f</b>) Weight ratio of PSBMA, PSBMA-L, and PSBMA-LM hydrogels at the natural environment for different periods. Inset: Images of the as-prepared hydrogels. (<b>g</b>) Images of PSBMA-LM hydrogel before and after stretching at −20 °C.</p>
Full article ">Figure 4
<p>(<b>a</b>) Relative resistance changes in PSBMA-LM hydrogel-based sensor under a strain of 3%. (<b>b</b>) Real-time monitoring of pulse based on PSBMA-LM sensors. (<b>c</b>) Photographs of PSBMA-LM hydrogel sensor attached to finger for monitoring the bending motion and the relative resistance change in the sensor with different bending angles. (<b>d</b>) The schematic diagram of monitoring of electromyographic signals during arm movement by flexible sensing system. (<b>e</b>) Characteristic amplitude changes when the human body is not attached. (<b>f</b>) Characteristic amplitude changes when connected to human muscle surface. (<b>g</b>) Characteristic amplitude changes during arm muscle centrifugal movement. (<b>h</b>) Characteristic amplitude changes during knee movement.</p>
Full article ">Figure 5
<p>(<b>a</b>) The working principle behind the handwriting letter recognition system based on a PSBMA-LM hydrogel sensor. (<b>b</b>) Schematic diagram of the machine learning image recognition process based on the ResNet18 model. (<b>c</b>) Detailed framework of the ResNet18 model. (<b>d</b>) Confusion matrix of image recognition results based on ResNet18.</p>
Full article ">
17 pages, 1405 KiB  
Article
Phytochemical Analysis and Biological Evaluation of Carob Leaf (Ceratonia siliqua L.) Crude Extracts Using NMR and Mass Spectroscopic Techniques
by Themistoklis Venianakis, Nikolaos Parisis, Atalanti Christou, Vlasios Goulas, Nikolaos Nikoloudakis, George Botsaris, Tjaša Goričan, Simona Golič Grdadolnik, Andreas G. Tzakos and Ioannis P. Gerothanassis
Molecules 2024, 29(22), 5273; https://doi.org/10.3390/molecules29225273 - 7 Nov 2024
Viewed by 496
Abstract
Carob leaves have gained attention for their bioactive properties and traditional medicinal uses, including as treatment for diabetes, digestive disorders, and microbial infections. The aim of this study was to explore the phytochemical composition of carob leaf acetone extracts using advanced spectroscopic techniques. [...] Read more.
Carob leaves have gained attention for their bioactive properties and traditional medicinal uses, including as treatment for diabetes, digestive disorders, and microbial infections. The aim of this study was to explore the phytochemical composition of carob leaf acetone extracts using advanced spectroscopic techniques. The combined use of heteronuclear nuclear magnetic resonance (NMR) experiments with 1D selective nuclear Overhauser effect spectroscopy (NOESY) offers detailed structural insights and enables the direct identification and quantification of key bioactive constituents in carob leaf extract. In particular, the NMR and mass spectrometry techniques revealed the presence of myricitrin as a predominant flavonoid, as well as a variety of glycosylated derivatives of myricetin and quercetin, in acetone extract. Furthermore, siliquapyranone and related gallotannins are essential constituents of the extract. The potent inhibitory effects of the carob leaf extract on Staphylococcus aureus (MIC = 50 μg mL−1) and a-glucosidase enzyme (IC50 = 67.5 ± 2.4 μg mL−1) were also evaluated. Finally, the antibacterial potency of carob leaf constituents were calculated in silico; digalloyl-parasorboside and gallic acid 4-O-glucoside exert a stronger bactericidal activity than the well-known myricitrin and related flavonoids. In summary, our findings provide valuable insights into the bioactive composition and health-promoting properties of carob leaves and highlight their potential for pharmaceutical and nutraceutical applications. Full article
Show Figures

Figure 1

Figure 1
<p>(<b>a</b>) 500 MHz <sup>1</sup>H NMR spectrum of the phenol-OH region of 20.14 mg carob leaf acetone extract in 500 μL DMSO-d<sub>6</sub>. (<b>b</b>) The same spectrum as in (<b>a</b>) after titration with trifluoroacetic acid solution in DMSO-d<sub>6</sub>. NMR spectra were acquired at 295 K and with 64 scans, 1.9 s acquisition time, and a relaxation delay of 4.0 s.</p>
Full article ">Figure 2
<p>800 MHz <sup>1</sup>H NMR spectrum of the expanded OH(5) region of flavonoids and their integrals relative to that of the major analyte myricetin-3-<span class="html-italic">O</span>-α- rhamnopyranoside (12.700 ppm).</p>
Full article ">Figure 3
<p>800 MHz <sup>1</sup>H-<sup>13</sup>C HMBC spectrum of the selected region of 20.14 mg carob leaf acetone extract in 500 μL DMSO-d<sub>6</sub>. Selected region of 800 MHz <sup>1</sup>H-<sup>13</sup>C HMBC spectrum of 20.14 mg carob leaf acetone extract in 500 μL DMSO-d<sub>6</sub>. The double arrows denote the connectivities of -OH(5) and -OH(7) with characteristic carbon atoms of myricetin-3-<span class="html-italic">O</span>-α-<span class="html-small-caps">l</span>-rhamnopyranoside. The spectrum was acquired at 298 K and with 56 scans and 1024 increments. The total experimental time was 14 h and 30 min.</p>
Full article ">Figure 4
<p>800 MHz HSQC-TOCSY spectrum of selected region of 20.14 mg carob leaf acetone extract in 500 μL DMSO-d<sub>6</sub>. Characteristic connectivities between the methyl carbon and all protons of the α-rhamnopyranoside ring are shown. The spectrum was acquired at 298 K and with 64 scans, 1024 increments, and a mixing time of 100 ms. The total experimental time was 1 day and 7 h.</p>
Full article ">Figure 5
<p>800 MHz 1D selective NOESY NMR spectrum of 20.14 mg carob leaf acetone extract in 500 μL DMSO-d<sub>6</sub>. The irradiated proton of myricetin-3-<span class="html-italic">O</span>-α-<span class="html-small-caps">l</span>-rhamnopyranoside is denoted with thunder and the protons showing connectivities are circled. The spectrum was acquired at 298 K and with 256 scans and a mixing time of 600 ms. The total experimental time was 30 min.</p>
Full article ">
13 pages, 3943 KiB  
Article
Towards the Mass Production of Molecularly Imprinted Polymers via Cost-Effective Photopolymerization Synthesis and Colorimetric Detection via Smartphone
by Kawtar Saidi, Dounia Elfadil and Aziz Amine
Chemosensors 2024, 12(11), 232; https://doi.org/10.3390/chemosensors12110232 - 7 Nov 2024
Viewed by 483
Abstract
The need for rapid, on-site contaminant detection is becoming increasingly vital for tackling environmental and public health challenges. This study introduces an efficient method for detecting sulfamethoxazole (SMX), a widely used antibiotic with significant environmental implications. A cost-effective, scalable approach was developed using [...] Read more.
The need for rapid, on-site contaminant detection is becoming increasingly vital for tackling environmental and public health challenges. This study introduces an efficient method for detecting sulfamethoxazole (SMX), a widely used antibiotic with significant environmental implications. A cost-effective, scalable approach was developed using lab-on-paper devices integrated with molecularly imprinted polymers (MIPs), synthesized through an in situ photopolymerization process that was completed in just 10 min. Using only 2 mL of MIP solution enabled the efficient mass production of 100 disks. Traditional template extraction, which often takes hours or days, was reduced to just 10 min using a multichannel micropipette and absorbent fabric. The MIP-PAD achieved a limit of detection (LOD) of 0.8 µg/mL and a limit of quantification (LOQ) of 2.4 µg/mL, with measurements obtained using a smartphone-based colorimetric detection system. It exhibited excellent repeatability, with a relative standard deviation (RSD) of 3.26% across seven tests, high reusability for up to eight cycles, and recovery rates for real samples ranging from 81.24% to 99.09%. This method provides notable improvements in sensitivity, reproducibility, and environmental sustainability over conventional techniques. The user-friendly platform integrating smartphone-based colorimetric detection is highly practical for real-time applications, offering broad potential for environmental monitoring, food safety, and healthcare. Full article
Show Figures

Graphical abstract

Graphical abstract
Full article ">Figure 1
<p>FT-IR spectra for PAD, MIP-PAD, and NIP-PAD.</p>
Full article ">Figure 2
<p>Template removal of SMX from MIP-PAD: monitoring green intensity changes across multiple extraction cycles.</p>
Full article ">Figure 3
<p>(<b>a</b>) Adsorption isotherms illustrating equilibrium adsorption capacity (mg/g). (<b>b</b>) Adsorption isotherms based on green intensity, evaluating the binding affinity of SMX on MIP-PAD compared to NIP-PAD.</p>
Full article ">Figure 4
<p>(<b>a</b>) Correlation analysis of red, green, and blue values with SMX concentrations ranging from 1 to 25 ppm. (<b>b</b>) Calibration curve for SMX detection using the PAD Method. (<b>c</b>) Calibration curve for SMX detection utilizing the smartphone-based MIP-PAD platform. Data are presented as means ± standard deviation (SD), with n = 3 replicates.</p>
Full article ">Figure 5
<p>Selective adsorption responses of the photopolymerized MIP-PAD for SMX, SMZ, SDZ, and SPD, each at a concentration of 25 ppm.</p>
Full article ">Figure 6
<p>Evaluation of repeatability in adsorption performance of the MIP-PAD with 25 ppm SMX concentration.</p>
Full article ">Figure 7
<p>Evaluation of the stability of MIP-PAD: a one-month assessment under various storage conditions to determine performance consistency and reliability.</p>
Full article ">Figure 8
<p>Evaluation of MIP-PAD reusability: study on performance retention and effectiveness across multiple use cycles.</p>
Full article ">Scheme 1
<p>Generalized scheme for UV-induced fabrication of SMX-photopolymerized MIP-PAD.</p>
Full article ">Scheme 2
<p>General scheme for template extraction from MIP-PAD via micropipette channel and visual monitoring for SMX removal.</p>
Full article ">
39 pages, 18258 KiB  
Article
Structural Health Monitoring and Failure Analysis of Large-Scale Hydro-Steel Structures, Based on Multi-Sensor Information Fusion
by Helin Li, Huadong Zhao, Yonghao Shen, Shufeng Zheng and Rui Zhang
Water 2024, 16(22), 3167; https://doi.org/10.3390/w16223167 - 5 Nov 2024
Viewed by 567
Abstract
Large-scale hydro-steel structures (LS-HSSs) are vital to hydraulic engineering, supporting critical functions such as water resource management, flood control, power generation, and navigation. However, due to prolonged exposure to severe environmental conditions and complex operational loads, these structures progressively degrade, posing increased risks [...] Read more.
Large-scale hydro-steel structures (LS-HSSs) are vital to hydraulic engineering, supporting critical functions such as water resource management, flood control, power generation, and navigation. However, due to prolonged exposure to severe environmental conditions and complex operational loads, these structures progressively degrade, posing increased risks over time. The absence of effective structural health monitoring (SHM) systems exacerbates these risks, as undetected damage and wear can compromise safety. This paper presents an advanced SHM framework designed to enhance the real-time monitoring and safety evaluation of LS-HSSs. The framework integrates the finite element method (FEM), multi-sensor data fusion, and Internet of Things (IoT) technologies into a closed-loop system for real-time perception, analysis, decision-making, and optimization. The system was deployed and validated at the Luhun Reservoir spillway, where it demonstrated stable and reliable performance for real-time anomaly detection and decision-making. Monitoring results over time were consistent, with stress values remaining below allowable thresholds and meeting safety standards. Specifically, stress monitoring during radial gate operations (with a current water level of 1.4 m) indicated that the dynamic stress values induced by flow vibrations at various points increased by approximately 2 MPa, with no significant impact loads. Moreover, the vibration amplitude during gate operation was below 0.03 mm, confirming the absence of critical structural damage and deformation. These results underscore the SHM system’s capacity to enhance operational safety and maintenance efficiency, highlighting its potential for broader application across water conservancy infrastructure. Full article
(This article belongs to the Special Issue Safety Monitoring of Hydraulic Structures)
Show Figures

Figure 1

Figure 1
<p>Four-level early warning method.</p>
Full article ">Figure 2
<p>Safety evaluation method.</p>
Full article ">Figure 3
<p>A conceptual framework of the structural health monitoring system.</p>
Full article ">Figure 4
<p>The architecture of an IoT-enabled structural health monitoring system.</p>
Full article ">Figure 5
<p>The overall layout of the project.</p>
Full article ">Figure 6
<p>Some existing defects of the target LS-HSS: (<b>a</b>) localized corrosion; (<b>b</b>) gate opening deviation and tilt; (<b>c</b>) water seal leakage.</p>
Full article ">Figure 7
<p>Diagrams of the spillway structure [<a href="#B48-water-16-03167" class="html-bibr">48</a>].</p>
Full article ">Figure 8
<p>The finite element model of the LS-HSS.</p>
Full article ">Figure 9
<p>Hydrostatic pressure distribution corresponding to different water levels.</p>
Full article ">Figure 10
<p>The equivalent stresses at a water depth of 6.5 m.</p>
Full article ">Figure 11
<p>Maximum equivalent stresses at water depths from 0 to 6.5 m.</p>
Full article ">Figure 12
<p>Maximum total deformation at water depths from 0 to 6.5 m.</p>
Full article ">Figure 13
<p>The flow field and load on the coupling surface in dynamic water conditions.</p>
Full article ">Figure 14
<p>Equivalent stress distribution (opening height: 1 m).</p>
Full article ">Figure 15
<p>Maximum equivalent stress at opening heights from 0 to 6.5 m.</p>
Full article ">Figure 16
<p>Maximum total deformation at opening heights from 0 to 6.5 m.</p>
Full article ">Figure 17
<p>Mode of vibration (partial).</p>
Full article ">Figure 18
<p>Arrangements of the strain-measuring points of the LS-HSS: (<b>a</b>) radial arm (left) arrangement of measuring points; (<b>b</b>) panel, beam, and girder arrangement of measuring points; (<b>c</b>) radial arm (right) arrangement of measuring points.</p>
Full article ">Figure 18 Cont.
<p>Arrangements of the strain-measuring points of the LS-HSS: (<b>a</b>) radial arm (left) arrangement of measuring points; (<b>b</b>) panel, beam, and girder arrangement of measuring points; (<b>c</b>) radial arm (right) arrangement of measuring points.</p>
Full article ">Figure 19
<p>Arrangements of vibration measuring points of LS-HSS: (<b>a</b>) radial arm (left) arrangement of measuring points; (<b>b</b>) panel, beam, and girder arrangement of measuring points; (<b>c</b>) radial arm (right) arrangement of the measuring points.</p>
Full article ">Figure 19 Cont.
<p>Arrangements of vibration measuring points of LS-HSS: (<b>a</b>) radial arm (left) arrangement of measuring points; (<b>b</b>) panel, beam, and girder arrangement of measuring points; (<b>c</b>) radial arm (right) arrangement of the measuring points.</p>
Full article ">Figure 20
<p>Arrangements of the tilt-measuring points of the LS-HSS.</p>
Full article ">Figure 21
<p>Sensors selected and installed on the LS-HSS: (<b>a</b>) dual-axis digital inclinometer; (<b>b</b>) capacitive accelerometer; (<b>c</b>) resistive strain gauges; (<b>d</b>) temperature and humidity anemometer.</p>
Full article ">Figure 22
<p>Sensors selected and installed on the hoist: (<b>a</b>) hydraulic system; (<b>b</b>) hydraulic cylinder; (<b>c</b>) automatic control system.</p>
Full article ">Figure 22 Cont.
<p>Sensors selected and installed on the hoist: (<b>a</b>) hydraulic system; (<b>b</b>) hydraulic cylinder; (<b>c</b>) automatic control system.</p>
Full article ">Figure 23
<p>The network architecture of the structural health monitoring system.</p>
Full article ">Figure 24
<p>Integrated interface for system functions.</p>
Full article ">Figure 25
<p>Data flow diagram of the integrated system functions.</p>
Full article ">Figure 26
<p>On-site testing conditions of the LS-HSS.</p>
Full article ">Figure 27
<p>The operational status of the hoist and control system.</p>
Full article ">Figure 28
<p>Analysis of online monitoring data under water-blocking conditions. (<b>a</b>) real-time monitoring data; (<b>b</b>) statistical analysis data.</p>
Full article ">Figure 29
<p>Analysis of online monitoring data under opening and closing conditions.</p>
Full article ">Figure 30
<p>Dynamic stress monitoring results.</p>
Full article ">
21 pages, 7713 KiB  
Article
Antioxidant and Protective Effects of Oleaster Oil Against Silica Nanoparticle-Induced Oxidative Stress and Organ Toxicity in Rats
by Malika Hamdiken, Amina Bouzitouna, Manel Hami, Yousra Seridi, Nedjoud Grara, Hayette Ayed, Abdelghani Boudjahem, Rabah Zebsa, Prospero Di Pierro, Andrea Balivo and Alessandro Genovese
Appl. Sci. 2024, 14(21), 10046; https://doi.org/10.3390/app142110046 - 4 Nov 2024
Viewed by 801
Abstract
Nanoparticles have found widespread application in a variety of fields, despite growing worry about their possible hazardous effects on both the environment and human health. In recent years, research efforts have focused on plants and vegetable oils, which have been identified as abundant [...] Read more.
Nanoparticles have found widespread application in a variety of fields, despite growing worry about their possible hazardous effects on both the environment and human health. In recent years, research efforts have focused on plants and vegetable oils, which have been identified as abundant sources of many bioactive compounds. Many of these substances are known to participate in antioxidant processes. As a result, the current study was designed to investigate the antioxidant and protective properties of oleaster oil against cytotoxicity and oxidative stress induced by silica nanoparticles (SiNPs) in albino Wistar rats. Forty male rats were randomly assigned to four equally sized cohorts: a control group, SiNP-treated group (at a dose of 50 mg/kg), SiNP-treated group supplemented with oleaster oil (at a dose of 2 mL/kg), and those receiving only 2 mL/kg of oleaster oil. The findings demonstrated that SiNPs initiated an oxidative stress environment, as evidenced by higher lipid peroxidation levels and changes in antioxidant defense mechanisms. Antioxidant enzymes were significantly reduced, including glutathione levels between the control and SiNP-exposure treatments (36.01%, 36.59%, 60%), glutathione-S-transferase (29.74%, 29.90%, 13.49%), catalase (24.14%, 28.19%, 30.85%), and tissue superoxide dismutase (11.90%, 37.78%, 37.79%) in the liver, kidney, and heart, respectively. Furthermore, histological investigations revealed significant liver, kidney, and heart damage, as indicated by pathological alterations such as vascular dilatation and congestion, inflammatory cellular infiltration, and hepatocellular dysfunction. Encouragingly, the administration of oleaster oil significantly ameliorated a majority of these detrimental effects. These data suggest a potential protective effect of oleaster oil against the adverse histological effects induced by SiNP injection. Full article
(This article belongs to the Section Chemical and Molecular Sciences)
Show Figures

Figure 1

Figure 1
<p>Chromatogram (TIC) of oleaster oil. Peaks: 1, ethanol; 2, hexanal; 3, isoamylacetate; 4, D-limonene; 5, 1-pentanol; 6, 2-pentylfuran; 7, β-cis-ocimene; 8, hexylacetate; 9, cis-3-hexenylacetate; 10, trans-2-heptenal; 11, nonanal; 12, acetic acid; 13, benzaldehyde; 14, trans-2-nonenal; 15, β-linalool; 16, 2-butyrolactone; 17, α-farnesene; 18, butanoic acid; 19, guaiacol; 20, 2-phenylethanol; 21, m-cresol; 22, nonanoic acid; 23, p-vinylguaiacol.</p>
Full article ">Figure 2
<p>DPPH radical scavenging activity as a function of the extract of oleaster oil.</p>
Full article ">Figure 3
<p>MDA levels with different treatments in the three organs: liver, kidney, and heart. Error bars represent the standard error. Matching letters above the bars denote no significant difference at <span class="html-italic">p</span> ≤ 0.05 following Tukey’s post hoc test (see <a href="#app1-applsci-14-10046" class="html-app">Supplementary Material</a>).</p>
Full article ">Figure 4
<p>GHS activity with different treatments in the three organs: liver, kidney, and heart. Error bars represent the standard error. Matching letters above the bars denote no significant difference at <span class="html-italic">p</span> ≤ 0.05 following Tukey’s post hoc test (see <a href="#app1-applsci-14-10046" class="html-app">Supplementary Material</a>).</p>
Full article ">Figure 5
<p>GST levels with different treatments in the three organs: liver, kidney, and heart. Error bars represent the standard error. Matching letters above the bars denote no significant difference at <span class="html-italic">p</span> ≤ 0.05 following Tukey’s post hoc test (see <a href="#app1-applsci-14-10046" class="html-app">Supplementary Material</a>).</p>
Full article ">Figure 6
<p>SOD levels in different treatments in the three organs: liver, kidney, and heart. Error bars represent the standard error. Matching letters above the bars denote no significant difference at <span class="html-italic">p</span> ≤ 0.05 following Tukey’s post hoc test (see <a href="#app1-applsci-14-10046" class="html-app">Supplementary Material</a>).</p>
Full article ">Figure 7
<p>The CAT level in different treatments in the three organs: liver, kidney, and heart. Error bars represent the standard error. Matching letters above the bars denote no significant difference at <span class="html-italic">p</span> ≤ 0.05 following Tukey’s post hoc tests (see <a href="#app1-applsci-14-10046" class="html-app">Supplementary Material</a>).</p>
Full article ">Figure 8
<p>Effect of oleaster oil on histopathologic damage in the liver after 5 weeks of treatment. Control group (C), (SiNPs) silica group. (SiNPs + Oleaster oil) Silica group treated with oleaster oil, and (O) Oleaster oil group.</p>
Full article ">Figure 9
<p>Effect of oleaster oil on histopathologic damage in the heart after 5 weeks of treatment. Control group (C), (SiNPs) silica group. (SiNPs + Oleaster oil) Silica group treated with oleaster oil, and (O) Oleaster oil group.</p>
Full article ">Figure 10
<p>Effect of oleaster oil on histopathologic damage in the kidney after 5 weeks of treatment. Control group (C), (SiNPs) silica group. (SiNPs + Oleaster oil) Silica group treated with oleaster oil, and (O) Oleaster oil group.</p>
Full article ">
17 pages, 2812 KiB  
Article
Characterization of Exopolysaccharides from Lactiplantibacillus plantarum PC715 and Their Antibiofilm Activity Against Hafnia alvei
by Xiqian Tan, Bingyu Ma, Xiaoqing Wang, Fangchao Cui, Xuepeng Li and Jianrong Li
Microorganisms 2024, 12(11), 2229; https://doi.org/10.3390/microorganisms12112229 - 3 Nov 2024
Viewed by 745
Abstract
Exopolysaccharides (EPSs) secreted by lactic acid bacteria have the potential to enhance human health by showing various biological functions. This study investigated the biological role and antibiofilm properties of EPS715, a new neutral EPS produced by pickled vegetables originating from Lactobacillus plantarum PC715. [...] Read more.
Exopolysaccharides (EPSs) secreted by lactic acid bacteria have the potential to enhance human health by showing various biological functions. This study investigated the biological role and antibiofilm properties of EPS715, a new neutral EPS produced by pickled vegetables originating from Lactobacillus plantarum PC715. The results indicate that EPS715 is primarily composed of rhamnose, glucose, and mannose. Its molecular weight (Mw) is 47.87 kDa, containing an α-glucoside linkage and an α-pyranose ring. It showed an amorphous morphology without a triple helix structure. Furthermore, EPS715 showed improved antioxidant activity. Specifically, its scavenging capacity of ABTS+ radicals, DPPH radicals, and the hydroxyl (·OH) reduction capacity at 5 mg/mL was 98.64 ± 2.70%, 97.37 ± 0.79%, and 1.64 ± 0.05%, respectively. Its maximal scavenging capacity was >40%, and the hydroxyl (·OH) radical scavenging ability was dose-dependent. Moreover, the biofilm of various pathogens including S. aureus, B. cereus, S. saprophyticus, Acinetobacter spp., and H. alvei was substantially dispersed and affected by EPS715, with a maximum inhibition rate of 78.17% for H. alvei. The possible mechanism by which EPS715 shows antibiofilm properties against the H. alvei may be attributed to its effects on the auto-aggregation, hydrophilic characteristics, and motility of Hafnia spp. Thus, EPS715 has significant antioxidant and antibiofilm characteristics that may hold substantial potential for applications in food and medicinal products. Full article
(This article belongs to the Section Food Microbiology)
Show Figures

Figure 1

Figure 1
<p>Spectral analysis of EPS715. (<b>a</b>) UV–Vis spectra; (<b>b</b>) FTIR spectra.</p>
Full article ">Figure 2
<p>The Mw and monosaccharide composition of EPS715. (<b>a</b>) GPC chromatogram of EPS715. The peak width was marked in the spectragram. (<b>b</b>) HPLC spectrum of the standard. (<b>c</b>) HPLC spectrum of the EPS hydrolates.</p>
Full article ">Figure 3
<p>Results of the Congo red experiment of EPS715.</p>
Full article ">Figure 4
<p>Microstructural and thermal characteristic analysis of EPS715. (<b>a</b>) SEM image of EPS715 at 1000×. (<b>b</b>) SEM image of EPS715 at 2000×. (<b>c</b>) XRD pattern. (<b>d</b>) DSC of EPS715.</p>
Full article ">Figure 5
<p>In vitro antioxidant activities of EPS715. (<b>a</b>) ABTS scavenging ability. (<b>b</b>) DPPH scavenging ability. (<b>c</b>) Hydroxyl radical scavenging. (<b>d</b>) Reducing power.</p>
Full article ">Figure 6
<p>The potential mechanism of EPS715 against <span class="html-italic">H. alvei</span>. (<b>a</b>) The effect of EPS715 on the growth of <span class="html-italic">H. alvei</span>. (<b>b</b>) The effects of EPS715 on the hydrophobicity of <span class="html-italic">H. alvei</span>. (<b>c</b>) The effects of EPS715 on the self-aggregation of <span class="html-italic">H. alvei</span>. (<b>d</b>) The effects of EPS715 on the swimming and swarming ability of <span class="html-italic">H. alvei.</span> ** (<span class="html-italic">p</span> &lt; 0.01), *** (<span class="html-italic">p</span> &lt; 0.001).</p>
Full article ">
16 pages, 3806 KiB  
Article
2SpamH: A Two-Stage Pre-Processing Algorithm for Passively Sensed mHealth Data
by Hongzhe Zhang, Jihui L. Diaz, Soohyun Kim, Zilong Yu, Yiyuan Wu, Emily Carter and Samprit Banerjee
Sensors 2024, 24(21), 7053; https://doi.org/10.3390/s24217053 - 31 Oct 2024
Viewed by 533
Abstract
Recent advancements in mobile health (mHealth) technology and the ubiquity of wearable devices and smartphones have expanded a market for digital health and have emerged as innovative tools for data collection on individualized behavior. Heterogeneous levels of device usage across users and across [...] Read more.
Recent advancements in mobile health (mHealth) technology and the ubiquity of wearable devices and smartphones have expanded a market for digital health and have emerged as innovative tools for data collection on individualized behavior. Heterogeneous levels of device usage across users and across days within a single user may result in different degrees of underestimation in passive sensing data, subsequently introducing biases if analyzed without addressing this issue. In this work, we propose an unsupervised 2-Stage Pre-processing Algorithm for Passively Sensed mHealth Data (2SpamH) algorithm that uses device usage variables to infer the quality of passive sensing data from mobile devices. This article provides a series of simulation studies to show the utility of the proposed algorithm compared to existing methods. Application to a real clinical dataset is also illustrated. Full article
(This article belongs to the Special Issue Wearable Sensing Technologies for Human Health Monitoring)
Show Figures

Figure 1

Figure 1
<p>A simulated example of downward bias introduced by duty-cycling algorithm. The vertical black and red lines represent the captured and uncaptured uploads of the true raw sensor data, respectively. The uncaptured uploads represent activity that is uncaptured by the sensor either because the sensor is off (due to duty-cycling) or the device is not being used or worn by the user. Each point, a daily aggregated step count, is derived as the sum of all uploads of raw sensor data from that day (black vertical lines), while the daily hypothetical upload is the sum of both the captured uploads (black vertical lines) and uncaptured uploads (red vertical lines) from that day. The upper trajectory of the dashed black line represents the trajectory of the true step count uploads while the lower trajectory of the solid line is the observed trajectory of captured step count uploads, an underestimation of the ground truth trajectory.</p>
Full article ">Figure 2
<p>Step-by-step illustration of the 2SpamH algorithm, where the size of each data point on the constructed feature space represents a daily observation of step count; (<b>a</b>) feature space construction with the first principal component of phone usage measures (<span class="html-italic">x</span>-axis), and the normalized number of step count uploads (<span class="html-italic">y</span>-axis); (<b>b</b>) prototype selection (red = “missing”, blue = “non-missing”); (<b>c</b>) k-nearest neighbors algorithm.</p>
Full article ">Figure 3
<p>Daily upload of step counts from the device of a single user over a three-week period, colored by the day of the week.</p>
Full article ">Figure 4
<p>The sensitivity and specificity performances of all three algorithms. Each block in the grids represent the algorithm performances at a specific activity level (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>L</mi> </mrow> <mrow> <mi>A</mi> </mrow> </msub> </mrow> </semantics></math>) and phone-usage level (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>L</mi> </mrow> <mrow> <mi>C</mi> </mrow> </msub> </mrow> </semantics></math>).</p>
Full article ">Figure 5
<p>Trajectory of step count data before and after applying 2SpamH and imputation. Data points are color-coded to differentiate their types: black (Point Type: Non-Missing after 2SpamH (Observed) dots represent the values of step counts of good quality observations identified by the 2SpamH algorithm; turquoise (Point Type: Missing after 2SpamH and Imputed) dots represent the values of step counts of poor-quality observations identified by the 2SpamH algorithm, which were then imputed using missForest; orange (Point Type: Missing from Technical Cause and Imputed) dots represent missing data points in the original data and then imputed using missForest; and gray (Point Type: Missing after 2SpamH (Observed)) dots represent the values of the observed step counts in the original data of poor-quality observations identified by 2SpamH. Note that each gray dot is connected to a turquoise dot by a dashed line since these are identified as missing by the 2SpamH algorithm and imputed. The blue curve shows the trend of the step counts after applying the 2SpamH algorithm and imputing missing data, while the red curve shows the trend before applying the algorithm. The figure demonstrates the effectiveness of 2SpamH in addressing the underestimation problem in passive measures.</p>
Full article ">Figure 6
<p>2SpamH algorithm for three users. Each point represents a daily observation of step count, the <span class="html-italic">x</span>-axis represents the first principal component of phone usage measures, and the <span class="html-italic">y</span>-axis represents the normalized number of uploads. The red-shaded areas in the lower left corners and blue-shaded areas in the upper right corners of each subplot represent prototypes with missing and non-missing labels, respectively. The size of the dots corresponds to the number of steps, with larger dots indicating higher step counts.</p>
Full article ">
Back to TopTop