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20 pages, 822 KiB  
Article
The Relevance of Plant-Based Diets and Micronutrient Supplementation for Body Composition: Data from the VeggieNutri Cross-Sectional Study
by Cátia Pinheiro, Flávia Silva, Inês Rocha, Carina Martins, Liliana Giesteira, Bruna Dias, Ana Lucas, Ana Margarida Alexandre, Catarina Ferreira, Bruna Viegas, Isabella Bracchi, Juliana Guimarães, Joana Amaro, Teresa F. Amaral, Cláudia Camila Dias, Andreia Oliveira, Altin Ndrio, João Tiago Guimarães, João Costa Leite, Rita Negrão and Elisa Keatingadd Show full author list remove Hide full author list
Nutrients 2024, 16(19), 3322; https://doi.org/10.3390/nu16193322 (registering DOI) - 30 Sep 2024
Abstract
Objectives: This study aimed to compare the anthropometry and body composition of vegetarian and omnivorous adults living in Portugal, while exploring nutritional and health parameters underlying observed differences. Methods: 425 omnivorous (OMNI), lacto-ovo-vegetarian (LOV), or vegan (VEG) healthy adults were recruited. Anthropometry was [...] Read more.
Objectives: This study aimed to compare the anthropometry and body composition of vegetarian and omnivorous adults living in Portugal, while exploring nutritional and health parameters underlying observed differences. Methods: 425 omnivorous (OMNI), lacto-ovo-vegetarian (LOV), or vegan (VEG) healthy adults were recruited. Anthropometry was measured, and bioelectrical impedance analysis was performed. Participants answered food frequency, sociodemographic, and lifestyle questionnaires. Serum iron, ferritin, and CRP were quantified by spectrophotometry, and serum B12 vitamin and homocysteine were quantified by chemiluminescent microparticle immunoassay. Results: Total protein intake significantly decreased with increasing strictness of vegetarian habits (median (P25; P75) in g/day: 98.6 (79.5; 123.1), 90.4 (65.9; 121.0), and 87.6 (59.8; 118.5) for OMNI, LOV and VEG, respectively; p = 0.020), and carbohydrate intake was the highest in LOV (median (P25; P75) in g/day: 231.5 (178.4; 287.9), 283.9 (227.3; 342.6), and 263.0 (222.0; 348.3) for OMNI, LOV and VEG, respectively; p = 0.001). VEG were the main users of B12 vitamin (93% in VEG vs. 17% in OMNI and 59% in LOV, p = 0.001), and LOV were the main users of iron supplements (29% in LOV vs. 14% in OMNI and 13% in VEG, p = 0.042), respectively. Blood levels of B12 vitamin correlated negatively with blood homocysteine (rs = −0.386, p < 0.001) and positively with % muscle mass (rs = 0.136, p = 0.005). Participants using iron supplements presented higher C-reactive protein (CRP) (p = 0.014) and they had lower % MM (p = 0.003). Finally, when compared to being OMNI, being LOV independently associated with: (a) having +4.8% (p = 0.002) of fat mass, which could be due to higher carbohydrate intake, and (b) having −2.2% (p = 0.043) of muscle mass. Our data suggest that the association between diet and muscle mass could be attenuated in VEG due to B12 supplementation and/or aggravated in LOV due to iron supplementation-associated inflammation. Full article
(This article belongs to the Special Issue Plant-Based Diet: Benefits and Concerns)
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<p>Recruitment flowchart of the VeggieNutri project.</p>
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<p>Sample distribution among adequacy categories for blood B12 vitamin (<b>A</b>) and ferritin (<b>B</b>), according to dietary group (LOV, lacto-ovo-vegetarians; OMNI, omnivorous; VEG, vegans). Sex-specific reference levels for blood ferritin and blood B12 vitamin set by the Clinical Pathology Department of CHUSJoão, Porto, Portugal were used as cut-offs of adequacy (<a href="#app1-nutrients-16-03322" class="html-app">Supplementary Materials Table S5</a>). Data are presented as relative frequencies. <sup>a</sup> Fisher’s exact test; <sup>b</sup> Chi- square test.</p>
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22 pages, 1841 KiB  
Article
Enhanced Impedance Control of Cable-Driven Unmanned Aerial Manipulators Using Fractional-Order Nonsingular Terminal Sliding Mode Control with Disturbance Observer Integration
by Li Ding, Tian Xia, Rui Ma, Dong Liang, Mingyue Lu and Hongtao Wu
Fractal Fract. 2024, 8(10), 579; https://doi.org/10.3390/fractalfract8100579 - 30 Sep 2024
Abstract
The article presents a novel control strategy for cable-driven aerial manipulators (UAMs) aimed at enhancing impedance control during contact operations in complex environments. A fractional-order nonsingular terminal sliding mode control (FONTSMC) integrated with a disturbance observer (DOB) is proposed to improve the robustness [...] Read more.
The article presents a novel control strategy for cable-driven aerial manipulators (UAMs) aimed at enhancing impedance control during contact operations in complex environments. A fractional-order nonsingular terminal sliding mode control (FONTSMC) integrated with a disturbance observer (DOB) is proposed to improve the robustness and precision of the UAM under lumped disturbances. This developed approach utilizes the flexibility of fractional calculus, the finite-time stability of nonsingular terminal sliding mode, and the real-time disturbance estimation capabilities of the DOB to ensure smooth and compliant contact interactions. The effectiveness of the proposed control strategy is validated through comprehensive simulation studies, which demonstrate significant improvements in control performance, stability, and disturbance rejection when compared to traditional methods. The results indicate that the FONTSMC-DOB framework is highly suitable for complex aerial manipulation tasks, offering both theoretical and practical insights into the design of advanced control systems for UAMs. Full article
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<p>UAM’s scheme.</p>
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<p>Architecture of FONTSM-DOB.</p>
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<p>Workspace of the aerial manipulator using the Monte Carlo method.</p>
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<p>Curve of the lumped disturbances.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>x</mi> <mrow> <mi>e</mi> <mi>x</mi> </mrow> </msub> </semantics></math> in Case 1.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>x</mi> <mrow> <mi>e</mi> <mi>z</mi> </mrow> </msub> </semantics></math> in Case 1.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>u</mi> <mi>x</mi> </msub> </semantics></math> in Case 1.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>u</mi> <mi>z</mi> </msub> </semantics></math> in Case 1.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>F</mi> <mrow> <mi>e</mi> <mi>x</mi> </mrow> </msub> </semantics></math> in Case 1.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>F</mi> <mrow> <mi>e</mi> <mi>z</mi> </mrow> </msub> </semantics></math> in Case 1.</p>
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<p>Trajectory of the aerial manipulator’s joint angles in joint-space.</p>
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<p>Trajectory of the aerial manipulator’s end-effector in workspace.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>x</mi> <mrow> <mi>e</mi> <mi>x</mi> </mrow> </msub> </semantics></math> in Case 2.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>x</mi> <mrow> <mi>e</mi> <mi>z</mi> </mrow> </msub> </semantics></math> in Case 2.</p>
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<p>STD of the tracking trajectories in Case 2.</p>
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<p>RSME of the tracking trajectories in Case 2.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>u</mi> <mi>x</mi> </msub> </semantics></math> in Case 2.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>u</mi> <mi>z</mi> </msub> </semantics></math> in Case 2.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>F</mi> <mrow> <mi>e</mi> <mi>x</mi> </mrow> </msub> </semantics></math> in Case 2.</p>
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<p>Response of <math display="inline"><semantics> <msub> <mi>F</mi> <mrow> <mi>e</mi> <mi>z</mi> </mrow> </msub> </semantics></math> in Case 2.</p>
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12 pages, 601 KiB  
Review
Detection of Porcine Circovirus (PCV) Using CRISPR-Cas12a/13a Coupled with Isothermal Amplification
by Huijuan Wang, Gang Zhou, Huiming Liu, Ruqun Peng, Tingli Sun, Sujuan Li, Mingjie Chen, Yingsi Wang, Qingshan Shi and Xiaobao Xie
Viruses 2024, 16(10), 1548; https://doi.org/10.3390/v16101548 - 30 Sep 2024
Abstract
The impact of porcine circovirus (PCV) on the worldwide pig industry is profound, leading to notable economic losses. Early and prompt identification of PCV is essential in managing and controlling this disease effectively. A range of detection techniques for PCV have been developed [...] Read more.
The impact of porcine circovirus (PCV) on the worldwide pig industry is profound, leading to notable economic losses. Early and prompt identification of PCV is essential in managing and controlling this disease effectively. A range of detection techniques for PCV have been developed and primarily divided into two categories focusing on nucleic acid or serum antibody identification. The methodologies encompass conventional polymerase chain reaction (PCR), real-time fluorescence quantitative PCR (qPCR), fluorescence in situ hybridization (FISH), loop-mediated isothermal amplification (LAMP), immunofluorescence assay (IFA), immunohistochemistry (IHC), and enzyme-linked immunosorbent assay (ELISA). Despite their efficacy, these techniques are often impeded by the necessity for substantial investment in equipment, specialized knowledge, and intricate procedural steps, which complicate their application in real-time field detections. To surmount these challenges, a sensitive, rapid, and specific PCV detection method using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas12a/13a coupled with isothermal amplification, such as enzymatic recombinase amplification (ERA), recombinase polymerase amplification (RPA), and loop-mediated isothermal amplification (LAMP), has been developed. This novel method has undergone meticulous optimization for detecting PCV types 2, 3, and 4, boasting a remarkable sensitivity to identify a single copy per microliter. The specificity of this technique is exemplary, with no observable interaction with other porcine viruses such as PEDV, PRRSV, PRV, and CSFV. Its reliability has been validated with clinical samples, where it produced a perfect alignment with qPCR findings, showcasing a 100% coincidence rate. The elegance of merging CRISPR-Cas technology with isothermal amplification assays lies in its on-site testing without the need for expensive tools or trained personnel, rendering it exceptionally suitable for on-site applications, especially in resource-constrained swine farming environments. This review assesses and compares the process and characteristics inherent in the utilization of ERA/LAMP/RPA-CRISPR-Cas12a/Cas13a methodologies for the detection of PCV, providing critical insights into their practicality and effectiveness. Full article
(This article belongs to the Section Animal Viruses)
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<p>Schematic diagram of the workflow of PCV detection employing the ERA/LAMP/RPA-CRISPR-Cas12a/Cas13a methodology. The comprehensive process can be divided into three stages. In the first stage, the genomic DNA of PCVs was first extracted. And then, the detected targets were amplified using ERA, LAMP, or RPA. In the second stage, the Cas12a or Cas13a protein would locate the target genes with the guidance of crRNA, and then the collateral activity of Cas12a/13a would be induced to cut the probes. In the third stage, the fluorescence signal will be activated using fluorescent equipment and can be observed using the naked eye. If not, the results can be seen as distinct lines when an LFD is submerged in the reaction tubes.</p>
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21 pages, 9179 KiB  
Article
Analysis of Influence of Grid-Following and Grid-Forming Static Var Generators on High-Frequency Resonance in Doubly Fed Induction Generator-Based Wind Farms
by Yong Sun, Hongbin Wu, Xiaozhe Song, Haifeng Zhang, Yifu Zhang, Jikai Chen and Hongpeng Liu
Electronics 2024, 13(19), 3879; https://doi.org/10.3390/electronics13193879 - 30 Sep 2024
Abstract
In Doubly Fed Induction Generator (DFIG)-based wind farms with Static Var Generators (SVGs), high-frequency resonance will be more like to occur when an unloaded cable is put into operation, which will threaten the stable operation of the wind farm. To address this issue, [...] Read more.
In Doubly Fed Induction Generator (DFIG)-based wind farms with Static Var Generators (SVGs), high-frequency resonance will be more like to occur when an unloaded cable is put into operation, which will threaten the stable operation of the wind farm. To address this issue, the influence of power outer loops on the impedance of grid-connected inverters is considered. Based on harmonic linearization, theoretical models for the sequence impedances of DFIGs, Grid-following (GFL) SVGs, and Grid-forming (GFM) SVGs are established. The correctness of the three models is verified by impedance scanning using the frequency sweep method. Through a comparative analysis of these sequence impedances, it is found that unlike the GFM SVG (which exhibits inductive impedance), the GFL SVG exhibits capacitive impedance in the high-frequency band, which leads to negative damping characteristics in the high-frequency band for the wind farm system with the grid-following SVG; thereby, the risk of high-frequency resonance also increases accordingly. On the contrary, GFM control adopted by SVGs can effectively eliminate the negative damping region in the high-frequency band for wind farms to suppress high-frequency resonance. Meanwhile, for grid-forming SVGs, the parameter variations in power synchronous loops have no significant impact on the suppressing effect of high-frequency resonance for wind farms. Finally, an electromagnetic simulation model for a DFIG-based wind farm system with an SVG is established using the StarSim-HIL (hardware-in-the-loop) experiment platform, and the simulation results validate the correctness of the theoretical analysis. Full article
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<p>Topology diagram of DFIG-based wind farm.</p>
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<p>DFIG stator side equivalent circuit and RSC control structure. (<b>a</b>) DFIG stator side equivalent circuit. (<b>b</b>) RSC control structure.</p>
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<p>GSC Control Structure Diagram.</p>
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<p>DFIG theoretical impedance model validation.</p>
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<p>GFL SVG control structure diagram.</p>
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<p>Control structure diagram of GFM SVG.</p>
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<p>Theoretical impedance model validation for GFL and GFM SVG.</p>
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<p>Equivalent circuit of the wind farm system.</p>
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<p>Effect of unload cable switching on the impedance of wind farm system.</p>
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<p>Effect of SVG voltage feedforward on the impedance of wind farm.</p>
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<p>Effect of two SVG control modes on the impedance of wind farm.</p>
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<p>Effect of inertia constant on system impedance of GFM SVG.</p>
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<p>Effect of damping coefficient on system impedance of GFM SVG.</p>
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<p>Pcc voltage and grid side current ① <span class="html-italic">u<sub>g</sub></span> (Amplitude: 1 pu/div, <span class="html-italic">t</span>: 22 ms/div); ② <span class="html-italic">i<sub>g</sub></span> (Amplitude: 0.5 pu/div, <span class="html-italic">t</span>: 22 ms/div).</p>
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<p>Fourier analysis of grid-side current during resonance process.</p>
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<p>Pcc voltage and grid-side current ① <span class="html-italic">u<sub>g</sub></span> (Amplitude: 1 pu/div, <span class="html-italic">t</span>: 120 ms/div); ② <span class="html-italic">i<sub>g</sub></span> (Amplitude: 0.5 pu/div, <span class="html-italic">t</span>: 120 ms/div).</p>
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<p>Fourier analysis of grid current when resonance disappearances.</p>
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<p>Reactive power output of SVG when <span class="html-italic">J</span> changes.</p>
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<p>Reactive power output of SVG when <span class="html-italic">D</span> changes.</p>
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<p>Flow chart.</p>
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<p>StarSim-HIL real-time experiment platform.</p>
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<p>Structural diagram.</p>
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14 pages, 4573 KiB  
Article
Catechol/m-Phenylenediamine Modified Sol–Gel Coating with Enhanced Long-Lasting Anticorrosion Performance on 3003 Al Alloy
by Keqi Huang, Xin Huang, Liyan Wang, Sifan Tu, Zi Yang, Honglei Guo, Bing Lei, Zhiyuan Feng and Guozhe Meng
Molecules 2024, 29(19), 4644; https://doi.org/10.3390/molecules29194644 - 30 Sep 2024
Abstract
Aluminum alloys, characterized by their low density and high mechanical strength, are widely applied in the manufacturing sector. However, the application of aluminum alloys in extreme environments presents severe corrosion challenges. Sol–gel organic coating techniques have garnered significant attention due to their excellent [...] Read more.
Aluminum alloys, characterized by their low density and high mechanical strength, are widely applied in the manufacturing sector. However, the application of aluminum alloys in extreme environments presents severe corrosion challenges. Sol–gel organic coating techniques have garnered significant attention due to their excellent stability, barrier properties, and cost-effectiveness, as well as their simpler processing. Nevertheless, conventional sol–gel coatings are unable to withstand the corrosive effects of high-chloride and high-halide ion environments such as marine conditions, owing to their inherent structural defects. Therefore, this study proposes the utilization of a simple method to synthesize catechol (CA) and meta-phenylenediamine (MPD)-derived catecholamine compounds to modify sol–gel coatings. Surface characteristics of the modified coatings were analyzed using Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The thickness of the modified coating was approximately 6.8 μm. The CA/MPD-modified substance effectively densifies the sol–gel coating, enhancing its corrosion protection performance. A 3.5 wt% NaCl solution was used to simulate a marine environment, and electrochemical impedance spectroscopy (EIS) was conducted using an electrochemical workstation to evaluate the coating’s protective properties over a long-term period. The results indicate that the modified coating provides protection for 3003 aluminum alloy for a minimum of 30 days under corrosive conditions, outperforming unmodified sol–gel coatings in terms of corrosion resistance. Full article
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<p>The reaction path of CA and MPD.</p>
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<p>EIS results from different sol–gel coatings on the surface of the aluminum alloy. (<b>a</b>) Bare sol–gel, (<b>b</b>) CA/MPD-0.1@sol–gel, (<b>c</b>) CA/MPD-2.0@sol–gel, (<b>d</b>) CA/MPD-4.0@solgel. The results showed that the best anticorrosion performance of the coating was achieved when the concentration of CA and MPD was 2.0 mg/L.</p>
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<p>Variation of low-frequency impedance (|Z|<sub>f = 0.01Hz</sub>) over time for sol–gel and different CA/MPD-modified sol–gel coatings immersed in a 3.5 wt% NaCl solution. It can be seen that the values of |Z|<sub>0.01Hz</sub> decrease slowly with the increase of soaking time, and CA/MPD-2.0@sol–gel has the best anticorrosion performance.</p>
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<p>UV-Vis absorption spectra of CA/MPD@sol–gel coatings. The results confirmed that the sol–gel coating was successfully modified by CA/MPD.</p>
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<p>FT-IR absorption spectra of CA/MPD@sol–gel coatings. (<b>a</b>) Full-spectrum range (4000–400 cm<sup>−1</sup>); (<b>b</b>) enlarged local range. Infrared findings strongly suggest that CA/MPD, drawing inspiration from the chemistry of mussels, effectively altered the sol–gel coating. 792 cm<sup>−1</sup>: Symmetric stretching of Si-O-Si. 1096 cm⁻<sup>1</sup>: Symmetric stretching vibrations of Si-O-Si. 906 cm<sup>−1</sup>: Epoxy groups. 2870 cm<sup>−1</sup> and 2926 cm<sup>−1</sup>: Symmetric and asymmetric stretching vibrations of C-H in GPTMS. 3395 cm<sup>−1</sup>: -OH groups introduced by catechol modification. 1650 cm⁻<sup>1</sup> to 1450 cm⁻<sup>1</sup>: Characteristic bands of aromatic rings. 3204 cm<sup>−1</sup> and 3058 cm<sup>−1</sup>: Catechol groups. 1150 cm<sup>−1</sup> to 1200 cm<sup>−1</sup>: C-N groups.</p>
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<p>XPS spectra of CA/MPD@sol–gel sample showing C 1s, N 1s, O 1s, and Si 2p peaks. The characteristic Si-OH and SiO<sub>x</sub> of the sol–gel were also detected on the surface, indicating that CA/MPD catecholamine substances did not merely form a new film on the sol–gel surface but interacted with it, altering the surface structure of the sol–gel coating.</p>
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<p>SEM images of surfaces of aluminum alloy substrate, sol–gel, and CA/MPD@sol–gel coatings, and the surface morphology after 30 days of immersion in 3.5 wt% NaCl solution No obvious defects were found in CA/MPD-modified sol–gel coating.</p>
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<p>Cross-sectional SEM and EDS analysis results of CA/MPD@sol–gel coating. The results indicated a uniform distribution of nitrogen across the cross-section.</p>
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<p>Depth profiling results of elemental distribution in the cross-section of CA/MPD@sol–gel coating by glow discharge optical emission spectroscopy (GD-OES). The relative amount of nitrogen in the cross-section of the modified coating showed a notable increase, suggesting that CA/MPD effectively penetrated the sol–gel coating during immersion and modified the entire coating.</p>
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<p>Comparison of water permeability rates for different coatings. This suggested that the penetration modification of CA/MPD greatly enhanced the compactness of the coating.</p>
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14 pages, 357 KiB  
Article
The Effects of the LiiNK Intervention on Physical Activity and Obesity Rates among Children
by David Farbo, Yan Zhang, Robyn Braun-Trocchio and Deborah J. Rhea
Int. J. Environ. Res. Public Health 2024, 21(10), 1304; https://doi.org/10.3390/ijerph21101304 - 30 Sep 2024
Abstract
Background: Obesity and inactivity among children are at an all-time high and have been steadily increasing in prevalence over the last thirty years. The school environment provides the ideal setting for reaching a large number of children across diverse populations in order to [...] Read more.
Background: Obesity and inactivity among children are at an all-time high and have been steadily increasing in prevalence over the last thirty years. The school environment provides the ideal setting for reaching a large number of children across diverse populations in order to reverse these trends. However, there are many inconsistent results yielded by school-based physical activity interventions due to implementation length, time for activities, and the use of structured physical activities. The LiiNK Project® is a whole-child intervention addressing these gaps by providing children 45–60 min of recess (unstructured, outdoor play) in their schools daily, while the control children are allowed to engage in recess for 30 min daily. The purpose of this study was to compare the physical activity intensity and obesity rates of third- and fourth-grade children participating in the LiiNK intervention, which provides 60 min of recess for third graders and 45 min for fourth graders, to those in a control group allowed 30 min of daily recess. Methods: The children were 8–10 years old (M = 9.2; 52% females and 48% males). The intervention children comprised 90 third graders and 100 fourth graders, and the control children comprised 101 third graders and 92 fourth graders. Physical activity levels were monitored using accelerometers to assess sedentary, light, and moderate-to-vigorous physical activity (MVPA). Obesity rates were evaluated using bio-electrical impedance analysis (BIA), in which body fat percentage is calculated based on normative values using age and sex in the equation. Results: The third-grade intervention children engaged in 13 more MVPA minutes and took 900 more steps daily than their control counterparts, and also presented a greater proportion of overweight children transitioning to a healthy weight status from the fall to the spring semester. Conversely, the fourth-grade control children increased their activity by 500 steps and 15 more MVPA minutes daily. Despite this, the intervention children overall demonstrated a reduction in body fat percentage, while the control children demonstrated an increase in body fat percentage. Conclusions: Ultimately, 60 min of unstructured, outdoor play in schools provides children the best opportunity to engage in MVPA, which may positively impact body fat percentages, offering a potential strategy for combatting childhood obesity in school settings. Full article
(This article belongs to the Special Issue Health Behavior and Health Promotion in Children and Adolescents)
16 pages, 1760 KiB  
Article
The Value of Pretherapeutic Basal Calcitonin Cut-Offs for the Therapeutic Strategy and Prediction of Long-Term Outcome of Patients with Medullary Thyroid Cancer—A 30-Year Single-Center Experience
by Martin B. Niederle, Teresa Binter, Philipp Riss, Bruno Niederle and Christian Scheuba
Cancers 2024, 16(19), 3343; https://doi.org/10.3390/cancers16193343 - 29 Sep 2024
Abstract
Background: The clinical relevance of clearly defined pretherapeutic basal calcitonin (bCt) cut-offs for predicting lymph node metastases (LNMs) and long-term outcomes (LOs) has so far not been tested in a large cohort of patients with medullary thyroid cancer included in a Ct screening [...] Read more.
Background: The clinical relevance of clearly defined pretherapeutic basal calcitonin (bCt) cut-offs for predicting lymph node metastases (LNMs) and long-term outcomes (LOs) has so far not been tested in a large cohort of patients with medullary thyroid cancer included in a Ct screening program during the initial diagnostic workup of thyroid nodules. Material and Methods: Female (f) patients with a bCt level of ≤23 pg/mL and male (m) patients with a level of ≤43 pg/mL were assigned to Group 1 (minimal oncologic risk), patients with a bCt between 24 and 84 pg/mL (f) and 44–99 pg/mL (m) to Group 2 (low oncologic risk), and those with a bCt of ≥85 pg/mL (f) and ≥100 pg/mL (m) to Group 3 (high oncologic risk). All patients underwent surgery applying a uniform surgical protocol. The median follow-up was 100 months. Results: The study included 306 patients. In 3/115 (2.6%) patients in Group 1 and in 3/50 (6.0%) in Group 2, LNM in the central but not lateral neck and no distant metastases (DMet) were documented. In both groups, the biochemical long-term cure rate was 95.7% and the disease-specific-survival (DSS) rate was 100% at 10, 15 and 20 years. Lateral LNM and DMet were diagnosed only in Group 3. The bCt levels of N0 and N1 patients showed broadly overlapping ranges, thus impeding the differentiation between those patients through bCt. Both the cure rate and DSS were significantly worse in Group 3. The overall biochemical long-term cure rate was 78.2%. Conclusions: Within a Ct screening program, grouping patients upon pretherapeutic bCt provides a simple risk classification system for indicating surgery, predicting LN involvement, and LOs. Full article
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<p>(<b>A</b>) Long-term disease-specific survival (DSS) of sporadic and hereditary (index) patients. (<b>B</b>) Long-term disease-specific survival (DSS) of patients with (N1) and without (N0) lymph node metastases (M0 only). (<b>C</b>) Long-term disease-specific survival (DSS) of patients with (M1) and without (M0) distant metastases.</p>
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<p>(<b>A</b>) Long-term disease-specific survival (DSS) of sporadic and hereditary (index) patients. (<b>B</b>) Long-term disease-specific survival (DSS) of patients with (N1) and without (N0) lymph node metastases (M0 only). (<b>C</b>) Long-term disease-specific survival (DSS) of patients with (M1) and without (M0) distant metastases.</p>
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<p>Long-term follow-up of patients assigned to three oncologic risk groups: Group 1—minimal oncologic risk; Group 2—low oncologic risk; Group 3—high oncologic risk; f: female; m: male; hered.: hereditary, LOF: loss of follow-up; FU: follow-up; Mo: month.</p>
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<p>Group 3—oncologic high-risk; individual bCt levels (pg/mL)—presence of lymph node metastases and long-term outcome. M1 excluded; N0: no lymph node metastases where n = 69; N1: lymph node metastases where n = 53; bCt: N0: 511 (IQR: 156–1034) pg/mL, N1: 715 (IQR: 284–1400) pg/mL (<span class="html-italic">p</span> = 0.135).</p>
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<p>Long-term disease-specific survival (DSS) of patients assigned to oncologic risk Group 1, Group 2, and Group 3.</p>
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17 pages, 4106 KiB  
Article
Enhancing Azo Dye Mineralization and Bioelectricity Generation through Biocathode-Microbial Fuel Cell Integration with Aerobic Bioreactor
by Kamran Ayaz, Ewa Zabłocka-Godlewska and Chao Li
Energies 2024, 17(19), 4896; https://doi.org/10.3390/en17194896 - 29 Sep 2024
Abstract
This study explores the efficient decolorization and complete mineralization of the diazo dye Evans blue, using an integrated aerobic bioreactor system coupled with a double-chamber microbial fuel cell (DCMFC) including a bio-cathode and acetate as a cosubstrate. The research addresses the environmental challenges [...] Read more.
This study explores the efficient decolorization and complete mineralization of the diazo dye Evans blue, using an integrated aerobic bioreactor system coupled with a double-chamber microbial fuel cell (DCMFC) including a bio-cathode and acetate as a cosubstrate. The research addresses the environmental challenges posed by dye-laden industrial effluents, focusing on achieving high decolorization efficiency and understanding the microbial communities involved. The study utilized mixed strains of actinomycetes, isolated from garden compost, to treat initial dye concentrations of 100 mg/L and 200 mg/L. Decolorization efficiency and microbial community composition were evaluated using 16S rRNA sequencing, and electrochemical impedance spectroscopy (EIS) was used to assess anode and DCMFC resistance. The results demonstrated decolorization efficiencies ranging from 90 ± 2% to 98 ± 1.9% for 100 mg/L and from 79 ± 2% to 87% ± 1% for 200 mg/L. An anode resistance of 12.48 Ω indicated a well-developed biofilm and enhanced electron transfer. The microbial community analysis revealed a significant presence of Pseudomonadota (45.5% in dye-acclimated cultures and 32% in inoculum cultures), with key genera including Actinomarinicola (13.75%), Thermochromatium (4.82%), and Geobacter (4.52%). This study highlights the potential of the integrated DCMFC–aerobic system, utilizing mixed actinomycetes strains, for the effective treatment of industrial dye effluents, offering both environmental and bioenergy benefits. Full article
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<p>Voltage output-time curves of MFCs with enrichment stage and after enrichment.</p>
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<p>Impact of EB concentrations on the production of bioelectric power (500 Ω external load).</p>
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<p>Polarization curves. a–b: power density as a function of current density in DCMFC.</p>
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<p>(<b>a</b>) UV–visible absorption spectra of 100 mg and 200 mg of DCMFC effluent, pure dye (control), and aerobically treated effluent. (<b>b</b>) Decolorization of EB in DCMFC with time.</p>
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<p>(<b>a</b>) UV–visible absorption spectra of 100 mg and 200 mg of DCMFC effluent, pure dye (control), and aerobically treated effluent. (<b>b</b>) Decolorization of EB in DCMFC with time.</p>
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<p>(<b>a</b>) Zero time and EB−enriched anode cyclic voltammetry in DCMFC, and (<b>b</b>) EIS Nyquist plots and fitted circuit drawings of the bioanode and DCMFC treated with EB.</p>
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<p>(<b>A</b>) SEM Images plain carbon brush at 1000× magnification. (<b>B</b>) SEM Images of anodic biofilm in the DCMFC at 5000× magnification.</p>
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<p>Microbial relative abundance at the (<b>a</b>) phylum and (<b>b</b>) genus level. (<b>c</b>) Phylogenetic tree of 16s RNA sequences of <span class="html-italic">Streptomyces</span> spp. (In = inoculum, E anode = enriched bioanode).</p>
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<p>Schematic diagram of double—chamber microbial fuel cell.</p>
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17 pages, 15641 KiB  
Article
Sliding Mode Observer-Based Phase-Locking Strategy for Current Source Inverter in Weak Grids
by Yubin Zheng, Hui Deng, Xiong Liu and Yuanpeng Guan
Energies 2024, 17(19), 4891; https://doi.org/10.3390/en17194891 - 29 Sep 2024
Abstract
The current source inverter (CSI) has become the main grid-connected interface of distributed generation systems due to its advantages, such as boost capability, current controllability, and short-circuit protection capability. However, in weak grids, the grid-connected CSI that uses a phase-locked loop to achieve [...] Read more.
The current source inverter (CSI) has become the main grid-connected interface of distributed generation systems due to its advantages, such as boost capability, current controllability, and short-circuit protection capability. However, in weak grids, the grid-connected CSI that uses a phase-locked loop to achieve grid voltage synchronization has problems, such as instability in the fundamental positive-sequence voltage phase detection at the point of common coupling and instability in the current loop control, which seriously hamper the promotion and application of the CSI and its interconnected systems. For this reason, this paper proposes a sliding mode observer-based phase-locking strategy for the CSI. The strategy proposes a sliding mode observer for grid voltage phase detection, so that the grid current can directly follow the grid voltage, solving the problem of inconsistency or distortion between the voltage phase of the point of common coupling and the grid voltage phase in weak grids. On this basis, the grid impedance is regarded as part of the CL filter, and a robust parameter design method is proposed for the grid current closed-loop control in weak grids, which achieves robust operation of a CSI in weak grids. Finally, an experimental platform for a single-phase grid-connected CSI is built to verify the effectiveness and feasibility of the proposed scheme. Full article
(This article belongs to the Section F3: Power Electronics)
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<p>System structure of single-phase grid-connected CSI based on PLL phase locking.</p>
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<p>Block diagram of SOGI-PLL.</p>
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<p>Structure of SMO.</p>
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<p>System structure of single-phase grid-connected CSI based on SMO phase locking.</p>
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<p>Block diagram of current control based on SMO phase locking in mixed <span class="html-italic">s</span>- and <span class="html-italic">z</span>-domain. (<b>a</b>) Current outer loop and damping inner loop structure. (<b>b</b>) Current outer loop and voltage inner loop structure.</p>
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<p>Block diagram of current control based on SMO phase locking in discrete <span class="html-italic">z</span>-domain.</p>
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<p>Bode diagram for different values of <span class="html-italic">f<sub>r</sub></span> and <span class="html-italic">K</span>.</p>
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<p>Three-dimensional graph of <span class="html-italic">K<sub>max</sub></span> changing with <span class="html-italic">K</span> and <span class="html-italic">L<sub>g</sub></span> when <span class="html-italic">f<sub>r</sub></span><sub>0</sub> &lt; <span class="html-italic">f<sub>s</sub></span>/6 and 0 &lt; <span class="html-italic">K</span> &lt; <span class="html-italic">K<sub>P</sub></span>.</p>
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<p>Bode diagram of PR controller varying with <span class="html-italic">K<sub>rc</sub></span>.</p>
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<p>Experiment setup of single-phase grid-connected CSI.</p>
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<p>Experimental waveforms of two phase-locking strategies when <span class="html-italic">L<sub>g</sub></span> = 0 mH.</p>
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<p>Experimental waveforms of two phase-locking strategies when <span class="html-italic">L<sub>g</sub></span> = 10 mH.</p>
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<p>Experimental waveforms of two phase-locking strategies when <span class="html-italic">L<sub>g</sub></span> = 20 mH.</p>
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<p>Experimental waveforms of two phase-locking strategies when <span class="html-italic">L<sub>g</sub></span> = 37 mH.</p>
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<p>Experimental waveforms of SMO-based current control system with a step change of current amplitude reference when <span class="html-italic">L<sub>g</sub></span> = 10 mH.</p>
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<p>Experimental waveforms of PLL-based current control system with a step change of current amplitude reference when <span class="html-italic">L<sub>g</sub></span> = 10 mH.</p>
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<p>Experimental waveforms of SMO-based current control system with a fluctuation of grid voltage frequency when <span class="html-italic">L<sub>g</sub></span> = 10 mH.</p>
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<p>Experimental waveforms of different sliding mode gains when <span class="html-italic">L<sub>g</sub></span> = 0 mH.</p>
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<p>Experimental waveforms of different proportional gains when <span class="html-italic">L<sub>g</sub></span> = 0 mH.</p>
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<p>Experimental waveform considering impedance measurement error when <span class="html-italic">L<sub>g</sub></span> = 37 mH.</p>
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24 pages, 7984 KiB  
Article
Design and Implementation of an Ultra-Wideband Water Immersion Antenna for Underwater Ultrasonic Sensing in Microwave-Induced Thermoacoustic Tomography
by Feifei Tan and Haishi Wang
Sensors 2024, 24(19), 6311; https://doi.org/10.3390/s24196311 - 29 Sep 2024
Abstract
Microwave-induced thermoacoustic tomography (MITAT) holds significant promise in biomedical applications. It creates images using ultrasonic sensors to detect thermoacoustic signals induced by microwaves. The key to generating thermoacoustic signals that accurately reflect the fact is to achieve sufficient and uniform microwave power absorption [...] Read more.
Microwave-induced thermoacoustic tomography (MITAT) holds significant promise in biomedical applications. It creates images using ultrasonic sensors to detect thermoacoustic signals induced by microwaves. The key to generating thermoacoustic signals that accurately reflect the fact is to achieve sufficient and uniform microwave power absorption of the testing target, which is closely tied to the microwave illumination provided by the antenna. In this article, we introduce a novel design and implementation of an ultra-wideband water immersion antenna for an MITAT system. We analyze and compare the advantages of selecting water as the background medium. Simulations are conducted to analyze the ultra-wideband characteristics in impedance matching, axial ratio, and radiation pattern of the proposed antenna. The measured |S11| shows good agreement with the simulated results. We also simulate the microwave power absorption of tumor and brain tissue, and the uniform microwave power absorption and high contrast between the tumor and brain indicate the excellent performance of the proposed antenna in the MITAT system. Full article
(This article belongs to the Special Issue Advanced Microwave Sensors and Their Applications in Measurement)
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<p>Block diagram of the process of MITAT.</p>
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<p>Histograms of acoustic impedance differences and microwave power losses when the four tissues are illuminated in mineral oil and water, respectively.</p>
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<p>Schema of the decomposed structures for the proposed antenna.</p>
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<p>Front views of the proposed radiating element.</p>
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<p>F The polarized ellipse and the transient components Ex and Ey of the electric field vector E.</p>
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<p>The simulated S<sub>11</sub> versus the distance between points P1 and P2.</p>
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<p>Front and back views of the proposed balun.</p>
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<p>The simulated S<sub>11</sub> versus the width of L1.</p>
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<p>Parameters of the proposed antenna.</p>
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<p>Axial ratios of the proposed antenna.</p>
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<p>Radiation patterns of XOZ and YOZ sections of the proposed antenna.</p>
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<p>Photographs of the proposed antenna: (<b>a</b>) is the inner circuits that contain the fabricated radiation element and balun, (<b>b</b>) is the full view of the fabricated antenna, and the black object is the shelter.</p>
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<p>Diagram of the testing system.</p>
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<p>Diagrams of the microwave absorption simulation models of the phantoms, (<b>a</b>) phantom 1; (<b>b</b>) phantom 2.</p>
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<p>Microwave absorption distribution map of phantom 1.</p>
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<p>The microwave absorption distribution maps of phantom 2 with different tumor diameters. A is tumor diameter, and T is phantom height.</p>
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<p>The microwave absorption distribution maps of phantom 2 with different tumor diameters. A is tumor diameter, and T is phantom height.</p>
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<p>The microwave power absorption distribution maps of phantom 2 with different phantom heights. A is the tumor diameter, and T is the phantom height.</p>
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16 pages, 2528 KiB  
Article
Effects of Magnetostatic Interactions in FeNi-Based Multilayered Magnetoimpedance Elements
by Grigory Yu. Melnikov, Sergey V. Komogortsev, Andrey V. Svalov, Alexander A. Gorchakovskiy, Irina G. Vazhenina and Galina V. Kurlyandskaya
Sensors 2024, 24(19), 6308; https://doi.org/10.3390/s24196308 - 29 Sep 2024
Abstract
Multilayered [Cu(3 nm)/FeNi(100 nm)]5/Cu(150 nm)/FeNi(10 nm)/Cu(150 nm)/FeNi(10 nm)/Cu(150 nm)/[Cu(3 nm)/FeNi(100 nm)]5 structures were obtained by using the magnetron sputtering technique in the external in-plane magnetic field. From these, multilayer magnetoimpedance elements were fabricated in the shape of elongated stripes using [...] Read more.
Multilayered [Cu(3 nm)/FeNi(100 nm)]5/Cu(150 nm)/FeNi(10 nm)/Cu(150 nm)/FeNi(10 nm)/Cu(150 nm)/[Cu(3 nm)/FeNi(100 nm)]5 structures were obtained by using the magnetron sputtering technique in the external in-plane magnetic field. From these, multilayer magnetoimpedance elements were fabricated in the shape of elongated stripes using the lift-off lithographic process. In order to obtain maximum magnetoimpedance (MI) sensitivity with respect to the external magnetic field, the short side of the rectangular element was oriented along the direction of the technological magnetic field applied during the multilayered structure deposition. MI sensitivity was defined as the change of the total impedance or its real part per unit of the magnetic field. The design of the elements (multilayered structure, shape of the element, etc.) contributed to the dynamic and static magnetic properties. The magnetostatic properties of the MI elements, including analysis of the magnetic domain structure, indicated the crucial importance of magnetostatic interactions between FeNi magnetic layers in the analyzed [Cu(3 nm)/FeNi(100 nm)]5 multilayers. In addition, the uniformity of the magnetic parameters was defined by the advanced technique of the local measurements of the ferromagnetic resonance field. Dynamic methods allowed investigation of the elements at different thicknesses by varying the frequency of the electromagnetic excitation. The maximum sensitivity of 40%/Oe with respect to the applied field in the range of the fields of 3 Oe to 5 Oe is promising for different applications. Full article
(This article belongs to the Special Issue Challenges and Future Trends of Magnetic Sensors)
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<p>Scheme of multilayered [Cu(3 nm)/FeNi(100 nm)]<sub>5</sub>/Cu (150 nm)/[FeNi (3 nm)/Cu(150 nm)/[FeNi (3 nm)/Cu(150 nm)/[FeNi(100 nm)/Cu(3 nm) ]<sub>5</sub> element in magnetoimpedance geometry. Ht—direction of the application of technological magnetic field during multilayered structure deposition. Iac—direction of the flow of the high frequency not alternating current during magnetoimpedance applications. Note that the structures are shown in their real scale (<b>a</b>). Photograph of 1–6 lithographic MI element arrangements; l is a length of 10 mm (<b>b</b>).</p>
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<p>Scheme of FMR measurements. Here, M is the magnetization vector, H is an external constant magnetic field, and h is a microwave rf field. For definition of all angles, see also the main text.</p>
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<p>VSM (<b>a</b>) and magneto-optical Kerr (<b>b</b>) in-plane magnetic hysteresis loops measured along the long (red curves) and short (black curves) sides of MI elements. Magnetic domain images obtained from both sides of the MI element A at zero magnetic field (<b>c</b>). Here “up” is for the measurements increasing in the external field starting from the saturation in the maximum negative field and “down” is for the measurements decreasing in the external field starting from the saturation in the maximum positive external field.</p>
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<p>Kerr microscopy surface magnetic hysteresis loops measured along the short side of MI elements with the scheme of magnetization of elements: (<b>a</b>) magnetization from −100 Oe to 100 Oe and back; (<b>b</b>) magnetization from −100 Oe to 0 Oe and back; (<b>c</b>) image of magnetic domains of MI element corresponding to the external magnetic field H<sub>ext</sub> = 7 Oe. Here “up” is for the measurements increasing in the external field starting from the saturation in the maximum negative field and “down” is for the measurements decreasing in the external field starting from the saturation in the maximum positive external field. Orientation of the external magnetic field is indicated by the red arrow; orientation of the magnetization of the top layer is indicated by the black arrow; orientation of the magnetization of the bottom layer is indicated by the blue arrow.</p>
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<p>(<b>a</b>) Dependence of the skin penetration depth on the value of the magnetic field at different frequencies of the exciting electromagnetic field for the f values in the range of the experimental studies. (<b>b</b>) The angular dependence of the resonant field for MI elements A and B at a frequency of 1.3 GHz. Lines 1 and 2 are theoretical calculations of <span class="html-italic">N<sub>x</sub></span> = 0.027 and <span class="html-italic">N<sub>x</sub></span> = 0.022, respectively, points of the experiment. (<b>c</b>) Distribution of <span class="html-italic">H<sub>a</sub></span> and <span class="html-italic">M<sub>eff</sub></span> values along the long side of MI element A.</p>
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<p>Schematic representation of the geometry of local FMR measurements for MI strip element: external magnetic field is applied along the long (<b>a</b>) and short (<b>b</b>) sides of the element. See also the main text.</p>
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<p>Frequency dependence of maximum MI ratio for real part of the impedance ratio (<b>a</b>); field dependence of MI ratio for resistance: (<b>b</b>,<b>c</b>) A, (<b>d</b>) B. Numbers in the legend correspond to the value of the frequency of the exciting current.</p>
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17 pages, 8199 KiB  
Article
Curriculum Design and Sim2Real Transfer for Reinforcement Learning in Robotic Dual-Arm Assembly
by Konstantin Wrede, Sebastian Zarnack, Robert Lange, Oliver Donath, Tommy Wohlfahrt and Ute Feldmann
Machines 2024, 12(10), 682; https://doi.org/10.3390/machines12100682 (registering DOI) - 29 Sep 2024
Abstract
Robotic systems are crucial in modern manufacturing. Complex assembly tasks require the collaboration of multiple robots. Their orchestration is challenging due to tight tolerances and precision requirements. In this work, we set up two Franka Panda robots performing a peg-in-hole insertion task of [...] Read more.
Robotic systems are crucial in modern manufacturing. Complex assembly tasks require the collaboration of multiple robots. Their orchestration is challenging due to tight tolerances and precision requirements. In this work, we set up two Franka Panda robots performing a peg-in-hole insertion task of 1 mm clearance. We structure the control system hierarchically, planning the robots’ feedback-based trajectories with a central policy trained with reinforcement learning. These trajectories are executed by a low-level impedance controller on each robot. To enhance training convergence, we use reverse curriculum learning, novel for such a two-armed control task, iteratively structured with a minimum requirements and fine-tuning phase. We incorporate domain randomization, varying initial joint configurations of the task for generalization of the applicability. After training, we test the system in a simulation, discovering the impact of curriculum parameters on the emerging process time and its variance. Finally, we transfer the trained model to the real-world, resulting in a small decrease in task duration. Comparing our approach to classical path planning and control shows a decrease in process time, but higher robustness towards calibration errors. Full article
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<p>Environment consisting of two robot arms, peg and hole workpieces. (<b>a</b>) Setup in simulation. (<b>b</b>) Setup in reality.</p>
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<p>Hierachical control system architecture with a central policy in form of a NN generating setpoints for the decentral low-level impedance controllers.</p>
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<p>Quantities describing the geometric relationship between the peg and the hole.</p>
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<p>Iterative training procedure of the dual-robot peg-in-hole task as reverse curriculum. Quantities represented by positions marked red will change if DR is activated.</p>
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<p>Return per training episode. Each color highlights a new iteration of the curriculum.</p>
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<p>Comparison of process time for the proposed RL-based control system in simulation and reality.</p>
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<p>Comparison of process time for the classical and the proposed RL-based control in reality.</p>
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<p>Comparison of EE forces during insertion of a squared peg for the classical and RL control strategy.</p>
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<p>Adaptation of the peg to a circular base area. Comparison of process time for the classical and the proposed RL-based control system in reality.</p>
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<p>Distribution of process cycle times for RL control with an injected base offset of 2 mm and 3 mm.</p>
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10 pages, 1381 KiB  
Article
Effect of Oral Zinc Supplementation on Phase Angle and Bioelectrical Impedance Vector Analysis in Duchenne Muscular Dystrophy: A Non-Randomized Clinical Trial
by Karina Marques Vermeulen-Serpa, Márcia Marilia Gomes Dantas Lopes, Camila Xavier Alves, Evellyn Camara Grilo, Thais Alves Cunha, Carolinne Thaisa de Oliveira Fernandes Miranda, Breno Gustavo Porfirio Bezerra, Lucia Leite-Lais, José Brandão-Neto and Sancha Helena de Lima Vale
Nutrients 2024, 16(19), 3299; https://doi.org/10.3390/nu16193299 - 29 Sep 2024
Abstract
Zinc plays a crucial role in cell structure and functionality. Neurodegenerative Duchenne muscular dystrophy (DMD) alters muscle membrane structure, leading to a loss of muscle mass and strength. The objective of this study was to evaluate the changes in phase angle (PA) and [...] Read more.
Zinc plays a crucial role in cell structure and functionality. Neurodegenerative Duchenne muscular dystrophy (DMD) alters muscle membrane structure, leading to a loss of muscle mass and strength. The objective of this study was to evaluate the changes in phase angle (PA) and bioelectrical impedance vector analysis (BIVA) results in patients with DMD after oral zinc supplementation. This clinical trial included 33 boys aged 5.6 to 24.5 years diagnosed with DMD. They were divided into three groups according to age (G1, G2, and G3) and supplemented with oral zinc. The mean serum zinc concentration was 74 μg/dL, and 29% of patients had concentrations below the reference value. The baseline values (mean (standard deviation)) of the bioelectrical impedance parameters PA, resistance (R), and reactance (Xc) were 2.59° (0.84°), 924.36 (212.31) Ω, and 39.64 (8.41) Ω, respectively. An increase in R and a decrease in PA and lean mass proportional to age were observed, along with a negative correlation (r = −0.614; p < 0.001) between age and PA. The average cell mass in G1 was greater than that in G3 (p = 0.012). There were no significant differences in serum zinc levels or bioelectrical impedance parameters before and after zinc supplementation. We conclude that this population is at risk of zinc deficiency and the proposed dosage of zinc supplementation was not sufficient to alter serum zinc levels, PA and BIVA results. Full article
(This article belongs to the Section Micronutrients and Human Health)
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<p>CONSORT flowchart for recruitment, selection, and analysis of participants.</p>
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<p>Confidence ellipses of 95% of impedance vectors measured before (T1) intervention with different groups (G1: black ellipse; G2: green ellipse; G3: purple ellipse).</p>
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<p>Confidence ellipses of 95% of impedance vectors measured before (T1: red ellipse) and after (T2: blue ellipse) oral zinc supplementation in DMD patients. The upward or downward displacement of the main axis is associated with larger or smaller cell mass, respectively.</p>
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15 pages, 2597 KiB  
Article
Electrical Tumor Detection Probe Calibrated to Diagnose Gastrointestinal Cancer Mass in Real-Time
by Narges Yousefpour, Habibollah Mahmoodzadeh, Reihane Mahdavi, Mohammad Reza Fattahi, Amirmohsen Jalaeefar, Hossein Ataee, Fereshteh Ameli, Farzane Hajighasemi, Hadi Mokhtari Dowlatabad, Sepideh Mansouri, Omid Nabavian, Seyed Rouhollah Miri and Mohammad Abdolahad
J. Clin. Med. 2024, 13(19), 5823; https://doi.org/10.3390/jcm13195823 (registering DOI) - 29 Sep 2024
Abstract
Background: The primary objective of this research is to propose an intra-operative tumor detection probe calibrated on human models of gastrointestinal (G.I.) cancers, enabling real-time scanning of dissected masses. Methods: Electrical Gastrointestinal Cancer Detection (EGCD) measures impedimetric characteristics of G.I. masses [...] Read more.
Background: The primary objective of this research is to propose an intra-operative tumor detection probe calibrated on human models of gastrointestinal (G.I.) cancers, enabling real-time scanning of dissected masses. Methods: Electrical Gastrointestinal Cancer Detection (EGCD) measures impedimetric characteristics of G.I. masses using a handpiece probe and a needle-based head probe. Impedance Phase Slope (IPS) and impedance magnitude (Z1kHz) are extracted as the classification parameters. EGCD was tested on palpable G.I. masses and compared to histopathology results. Results: Calibration was carried out on 120 GI mass samples. Considering pathological results as the gold standard, most cancer masses showed Z1kHz between 100 Ω and 2500 Ω while their IPS was between −15 and −1. The EGCD total sensitivity and specificity of this categorization in G.I. cancer patients with palpable tumors were 86.4% and 74.4%, respectively (p-value < 0.01). Conclusion: EGCD scoring can be used for 3D scanning of palpable tumors in G.I. tumors during surgery, which can help clarify the tumors’ pathological response to neoadjuvant chemotherapy or the nature of intra-operative newly found G.I. tumors for the surgeon to manage their surgical procedure better. Full article
(This article belongs to the Special Issue Gastrointestinal Endoscopy: Recent Developments and Emerging Trends)
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<p>The EGCD’s read-out system and function. (<b>A</b>) EGCD handpiece. (<b>B</b>) An enlarged view of the head probe illustrates the needle dispersion’s associated dimension. (<b>C</b>) Structure of tumoral gastric. (<b>D</b>) EGCD applies to the tumoral gastric, where the tumor invades the outer lining.</p>
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<p>The study inclusion and exclusion in the cohort study.</p>
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<p>Simulation of normalized current density in EGCD for f = 1 KHz and configuration of longitudinal proximity of cancerous mass. (<b>A</b>) Representation of max electrical current density at electrode places. The 1-3 is top view of the electrodes configuration. It is worth mentioning that the electrodes named 1 and 2 have the same potential to increase the measurement area. The simulation showed that the tip of the needles is the most sensitive electrode of the head probe. (<b>B</b>) Simulation of electrical current penetration depth into the cancerous tumor in the different distances of the tumor from the tips of needles. (<b>C</b>) A two-dimensional diagram representing tumor distance from the tip of the needle on the <span class="html-italic">x</span>-axis and current density on the <span class="html-italic">y</span>-axis for all different distances of tumor from the tips of needles defines that the transition point of the EGCD head probe is about 0.5 mm from the needle tip.</p>
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<p>EGCD measurement, calibration, and scoring schematic at G.I. tract. (<b>A</b>) Structure of sizeable tumoral lesion in rectosigmoid junction. (<b>B</b>) The surgeon applied the EGCD probe to the dissected tumoral mass. (<b>C</b>) A magnified view of the layer structure of the mass that the EGCD encounters during measurement. (<b>D</b>) H&amp;E assay of post-surgical pathology evaluation of the tumoral tissue. (<b>E</b>) A two-dimensional scattered diagram representing Z1kHz on the <span class="html-italic">x</span>-axis and IPS on the <span class="html-italic">y</span>-axis for all tested samples defines a primary calibration cut-off set. The green area is supposed to represent the negative region with the highest probability of benignity in G.I. samples. In contrast, the patterned red rectangle represents the positive region with the highest likelihood of malignancy in GIC samples. (<b>F</b>,<b>G</b>) Receiver operating characteristic (ROC) and comparison of AUC and <span class="html-italic">p</span>-value for IPS, Z1kHz, EGCD score, radiology score (RADS), age, and sex as the classification parameters.</p>
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<p>Picture of the H&amp;E assay of G.I. mass and comparison of EGCD score, post-treatment imaging evaluation, and post-surgical pathology evaluation of each case. (<b>A</b>) The rectal mass is free of tumors. (<b>B</b>) Gastric mass involved by adenocarcinoma. (<b>C</b>) Esophagus mass involved by SCC. (<b>D</b>) Esophagus mass involved by SCC.</p>
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12 pages, 444 KiB  
Article
Progress and Challenges in Canada’s Path Toward the Elimination of Cervical Cancer
by Samara Perez
Curr. Oncol. 2024, 31(10), 5850-5861; https://doi.org/10.3390/curroncol31100435 (registering DOI) - 29 Sep 2024
Abstract
Cervical cancer is almost entirely preventable and treatable when detected early, making its elimination within reach for Canada and the world. However, cervical cancer is now the fastest-increasing cancer (+3.7% per year since 2015) in Canada as of 2023, marking the first significant [...] Read more.
Cervical cancer is almost entirely preventable and treatable when detected early, making its elimination within reach for Canada and the world. However, cervical cancer is now the fastest-increasing cancer (+3.7% per year since 2015) in Canada as of 2023, marking the first significant increase in cervical cancer incidence since 1984. The human papillomavirus (HPV) vaccine and cervical screening are key preventive measures, with targets set by the WHO and the Canadian Partnership Against Cancer (CPAC) to eliminate cervical cancer in Canada by 2030 and 2040, respectively. These targets include increasing HPV vaccination rates, implementing primary HPV screening, and improving follow-up for abnormal HPV+ results. However, Canada’s progress has been impeded by significant challenges. As of the most recent data, HPV vaccine coverage rates in Canada range from 47% to 81%, with an estimated national HPV vaccination completion rate of 64% in Canada, far below the target of 90% by 2025 set by the CPAC. With the exception of British Columbia and Prince Edward Island, the adoption of HPV DNA testing as the primary screening method has been slow across the Canadian provinces and territories despite its superior sensitivity compared with traditional cytology. This article reviews the current state of HPV vaccination and screening in Canada, emphasizing the need for coordinated efforts, transparency, and resource sharing to overcome barriers. Key recommendations include the dissemination of accessible educational materials, partnerships, and collaboration, including nationwide task forces and roundtables, and the implementation of standardized guidelines for HPV screening. Achieving cervical cancer elimination requires a united approach involving federal, provincial, and territorial health authorities, researchers, clinicians, NGOs, community groups, and patients’ voices working together to ensure consistent, effective, timely, and meaningful cervical cancer prevention strategies are used across the country. Full article
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Figure 1

Figure 1
<p>HPV vaccine completion rates by province.</p>
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