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Search Results (3,083)

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Keywords = longevity

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13 pages, 1965 KiB  
Article
The Impact of Ten Days of Periodic Fasting on the Modulation of the Longevity Gene in Overweight and Obese Individuals: A Quasi-Experimental Study
by Nurma Yuliyanasari, Eva Nabiha Zamri, Purwo Sri Rejeki and Muhammad Miftahussurur
Nutrients 2024, 16(18), 3112; https://doi.org/10.3390/nu16183112 - 15 Sep 2024
Viewed by 397
Abstract
Background: Fasting potentially alters the aging process induced by obesity by regulating telomere integrity, which is related to longevity genes. However, the impact of periodic fasting (PF) on the expression of longevity genes, particularly Forkhead Box O Transcription Factors (FOXO3a) and the Human [...] Read more.
Background: Fasting potentially alters the aging process induced by obesity by regulating telomere integrity, which is related to longevity genes. However, the impact of periodic fasting (PF) on the expression of longevity genes, particularly Forkhead Box O Transcription Factors (FOXO3a) and the Human Telomerase Reverse Transcriptase (hTERT), is not fully understood. This study aimed to analyze the effects of PF, specifically on FOXO3a, hTERT expression, and other associated factors. Methods: A quasi-experimental 10-day study was conducted in Surabaya, East Java, Indonesia. This study consisted of an intervention group (PFG), which carried out PF for ten days using a daily 12 h time-restricted eating protocol, and a control group (CG), which had daily meals as usual. FOXO3a and hTERT expression were analyzed by quantitative real-time qPCR. A paired t-test/Wilcoxon test, independent t-test/Mann–Whitney U-test, and Spearman’s correlation test were used for statistical analysis. Result: Thirty-six young men participated in this study. During the post-test period, FOXO3a expression in the PFG increased 28.56 (±114.05) times compared to the pre-test, but the difference was not significant. hTERT expression was significantly higher in both the CG and PFG. The hTERT expression in the PFG was 10.26 (±8.46) times higher than in the CG, which was only 4.73 (±4.81) times higher. There was also a positive relationship between FOXO and hTERT in the CG. Conclusions: PF significantly increased hTERT expression in the PFG; however, no significant increase was found in FOXO3a expression. PF regimens using the 12 h time-restricted eating approach may become a potential strategy for preventing obesity-induced premature aging by regulating longevity gene expression. Full article
(This article belongs to the Section Nutrition and Obesity)
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<p>Research workflow.</p>
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<p>Effects of PF on glucose and lipid profiles after 10 days. (<b>a</b>) FBG level in the CG; (<b>b</b>) FBG level in the PFG; (<b>c</b>) TC level in the CG; (<b>d</b>) TC level in the PFG. The difference between pre-test and post-test data was analyzed using the paired <span class="html-italic">t</span>-Test or Wilcoxon test. (**) indicates a significant difference.</p>
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<p>The difference in FOXO3a expression of the participants. (<b>a</b>) dCT of FOXO3a in the CG; (<b>b</b>) FOXO3a relative expression from ΔΔCt in the CG; (<b>c</b>) dCT of FOXO3a in the PFG; (<b>d</b>) FOXO3a relative expression from ΔΔCt in the PFG. The difference between pre-test and post-test data was analyzed using the paired <span class="html-italic">t</span>-test or Wilcoxon test.</p>
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<p>The difference in hTERT expression of the participants. (<b>a</b>) dCT of hTERT in the CG; (<b>b</b>) hTERT relative expression from ΔΔCt in the CG; (<b>c</b>) dCT of hTERT in the PFG; (<b>d</b>) hTERT relative expression from ΔΔCt in the PFG. The difference between pre-test and post-test data was analyzed using the paired <span class="html-italic">t</span>-test or Wilcoxon test. (**) indicates a significant difference.</p>
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22 pages, 1397 KiB  
Article
A Bis(Acridino)-Crown Ether for Recognizing Oligoamines in Spermine Biosynthesis
by Péter Kisfaludi, Sára Spátay, Marcell Krekó, Panna Vezse, Tünde Tóth, Péter Huszthy and Ádám Golcs
Molecules 2024, 29(18), 4390; https://doi.org/10.3390/molecules29184390 - 15 Sep 2024
Viewed by 283
Abstract
Oligoamines in cellular metabolism carry extremely diverse biological functions (i.e., regulating Ca2+-influx, neuronal nitric oxide synthase, membrane potential, Na+, K+-ATPase activity in synaptosomes, etc.). Furthermore, they also act as longevity agents and have a determinative role in [...] Read more.
Oligoamines in cellular metabolism carry extremely diverse biological functions (i.e., regulating Ca2+-influx, neuronal nitric oxide synthase, membrane potential, Na+, K+-ATPase activity in synaptosomes, etc.). Furthermore, they also act as longevity agents and have a determinative role in autophagy, cell growth, proliferation, and death, while oligoamines dysregulation is a key in a variety of cancers. However, many of their mechanisms of actions have just begun to be understood. In addition to the numerous biosensing methods, only a very few simple small molecule-based tests are available for their selective but reversible tracking or fluorescent labeling. Motivated by this, we present herein a new fluorescent bis(acridino)-crown ether as a sensor molecule for biogenic oligoamines. The sensor molecule can selectively distinguish oligoamines from aliphatic mono- and diamino-analogues, while showing a reversible 1:2 (host:guest) complexation with a stepwise binding process accompanied by a turn-on fluorescence response. Both computational simulations on molecular docking and regression methods on titration experiments were carried out to reveal the oligoamine-recognition properties of the sensor molecule. The new fluorescent chemosensor molecule has a high potential for molecular-level functional studies on the oligoamine systems in cell processes (cellular uptake, transport, progression in cancers, etc.). Full article
4 pages, 177 KiB  
Editorial
Reconsidering “Aging Well” According to Multiple Definitions: A Multidimensional Approach to Clinical Psychology of Aging
by Luca Gaviano, Roberto Pili, Andrea Domenico Petretto, Roberta Berti, Gian Pietro Carrogu, Martina Pinna and Donatella R. Petretto
Geriatrics 2024, 9(5), 120; https://doi.org/10.3390/geriatrics9050120 - 15 Sep 2024
Viewed by 195
Abstract
Aging is a phase of life that, though inevitable, includes an extraordinary variety of experiences, challenges, and opportunities [...] Full article
16 pages, 315 KiB  
Review
Searching for Beauty and Health: Aging in Women, Nutrition, and the Secret in Telomeres
by Virginia Boccardi and Joanna Polom
Nutrients 2024, 16(18), 3111; https://doi.org/10.3390/nu16183111 - 15 Sep 2024
Viewed by 903
Abstract
Women typically outlive men, yet they often experience greater frailty and a higher incidence of chronic diseases as they age. By exploring the biological foundations of aging, with a particular focus on telomere dynamics, this manuscript aims to describe how dietary and lifestyle [...] Read more.
Women typically outlive men, yet they often experience greater frailty and a higher incidence of chronic diseases as they age. By exploring the biological foundations of aging, with a particular focus on telomere dynamics, this manuscript aims to describe how dietary and lifestyle choices can significantly influence the aging process. The review comprehensively examines current research, underscoring the power of nutrition to counteract age-related changes, support healthy aging, and maintain vitality and beauty in women. The exploration of telomeres—the protective caps at the ends of chromosomes—reveals how they serve as markers of cellular aging and are potential targets for interventions aimed at enhancing women’s longevity and quality of life. This study also emphasizes the importance of sex-specific approaches and precision medicine in understanding the unique health challenges women face as they age. By proposing targeted strategies, the review seeks to address these challenges, offering insights into preventive measures that can foster resilience, promote well-being, and extend healthy life expectancy in women. Ultimately, this work provides a sophisticated understanding of the aging process in women, highlighting the pivotal role of tailored interventions in preserving both health and beauty. Full article
(This article belongs to the Section Nutrition in Women)
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12 pages, 4156 KiB  
Article
Involvement of Aryl Hydrocarbon Receptor in Longevity and Healthspan: Insights from Humans, Mice, and C. elegans
by Eva Serna, David Verdú, Alicia Valls, Ángel Belenguer-Varea, Francisco José Tarazona-Santabalbina, Consuelo Borrás and José Viña
Int. J. Mol. Sci. 2024, 25(18), 9943; https://doi.org/10.3390/ijms25189943 (registering DOI) - 14 Sep 2024
Viewed by 298
Abstract
In previous studies, using transcriptomic analysis, we observed higher levels of aryl hydrocarbon receptor (AHR) gene expression in the peripheral blood cells of centenarians compared to octogenarians. This suggests the potential significance of this receptor in maintaining physiological balance and promoting healthy aging, [...] Read more.
In previous studies, using transcriptomic analysis, we observed higher levels of aryl hydrocarbon receptor (AHR) gene expression in the peripheral blood cells of centenarians compared to octogenarians. This suggests the potential significance of this receptor in maintaining physiological balance and promoting healthy aging, possibly linked to its critical role in detoxifying xenobiotics. In our current study, we confirmed that AHR expression is indeed higher in centenarians. We employed C. elegans as a model known for its suitability in longevity studies to explore whether the AHR pathway has a significant impact on lifespan and healthspan. Our survival assays revealed that two different mutants of AHR-1 exhibited lower longevity. Additionally, we used a mouse model to examine whether supplementation with pomegranate extract modulates the expression of AHR pathway genes in the liver. Furthermore, we studied a nutritional strategy based on pomegranate extract administration to investigate its potential modulation of life- and healthspan in worms. Full article
(This article belongs to the Special Issue Health Promoting Benefits of Natural Products and Functional Foods)
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Figure 1
<p>Graphical summary of AHR canonical pathway that is up-regulated in centenarians.</p>
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<p>Correlation of all genes involved in the AHR canonical pathway. Circle symbols represent the correlation between <span class="html-italic">AHR</span> and <span class="html-italic">ARNT</span>, square symbols represent the correlation between <span class="html-italic">AHR</span> and <span class="html-italic">CYP1B1,</span> and triangle symbols represent the correlation between <span class="html-italic">AHR</span> and <span class="html-italic">NFE2L2</span>.</p>
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<p>Survival curves of <span class="html-italic">C. elegans</span> mutants ahr-1 (ju145) (<b>Panel A</b>) and ahr-1 (ia3), (<b>Panel B</b>) compared with wild-type strain (N2). Data correspond to <span class="html-italic">n</span> = 200 worms/condition. <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>Effect of PE 0.05 mg/mL on lifespan in mutants <span class="html-italic">C. elegans</span> ahr-1 (ju145) (<b>Panel A</b>) and ahr-1 (ia3) (<b>Panel B</b>) in comparison with wild-type strain (N2). Data corresponded to <span class="html-italic">n</span> = 100 worms/condition. PE: pomegranate extract.</p>
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<p>The effect of PE supplementation 0.05 mg/mL on <span class="html-italic">C elegans</span> motility at different ages. The 100% value is the motility of control worms (vehicle) at 1 day of the adult stage. PE: pomegranate extract. <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Effect of PE supplementation on expression of <span class="html-italic">Ahr</span> (<b>Panel A</b>), <span class="html-italic">Arnt</span> (<b>Panel B</b>), <span class="html-italic">Cyp1b1</span> (<b>Panel C</b>), and <span class="html-italic">Nfe2l2</span> (<b>Panel D</b>) in mouse liver. Results are expressed as mean ± SEM (<span class="html-italic">n</span> = 5–6 per group). * <span class="html-italic">p</span> &lt; 0.05.</p>
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7 pages, 798 KiB  
Perspective
Meta-Research in Geriatric Surgery: Improving the Quality of Surgical Evidence for Older Persons in a Multidimensional-Scale Research Field
by Ivan David Lozada-Martinez, David A. Hernandez-Paez, Isabela Palacios Velasco, Darly Martinez Guevara and Yamil Liscano
J. Clin. Med. 2024, 13(18), 5441; https://doi.org/10.3390/jcm13185441 - 13 Sep 2024
Viewed by 290
Abstract
The world is facing a significant demographic transition, with a substantial increase in the proportion of older persons, as well as long-lived persons (especially nonagenarians and centenarians). One of the popular beliefs is that old age is synonymous with disease and disability. However, [...] Read more.
The world is facing a significant demographic transition, with a substantial increase in the proportion of older persons, as well as long-lived persons (especially nonagenarians and centenarians). One of the popular beliefs is that old age is synonymous with disease and disability. However, the successful aging hypothesis suggests that those older persons with advanced chronological age who maintain their functional capacity derive from it a delay in biological aging, enhancing the quality of organic aging and regulation. Therefore, regardless of chronological age, even in cases of extreme longevity, those older adults with a successful aging phenotype and favorable functional capacity would be expected to have satisfactory post-surgical recovery with a low risk of morbidity and mortality. Currently, there is a significant gap between the availability of high-certainty surgical evidence that allows for evidence-based interventions applicable to the long-lived population—taking into account the actual conditioning factors of the health phenotype in older persons—and, above all, predictors of satisfactory post-surgical evolution. The application of meta-research to geriatric surgery emerges as a fundamental tool to address this knowledge gap and reveals opportunities and limitations that need to be resolved in the near future to establish evidence-based surgical care for older persons. The aim of this manuscript was to present a real and globally relevant scenario related to surgical care, addressing the longevity, the availability, and the quality of surgical evidence applicable to this population, and also to present variables to consider in analysis and future perspectives in research and meta-research in geriatric surgery. Full article
(This article belongs to the Section General Surgery)
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<p>Surgical studies registered in <a href="http://clinicaltrials.gov" target="_blank">clinicaltrials.gov</a> related to long-lived persons.</p>
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<p>The relationship between the number of publications on surgical research in nonagenarians and centenarians in PubMed (data as of 21 August 2024), and the increase in the world’s long-lived population ratio over time. The long-lived population ratio was obtained by dividing the number of people in the specific age group (nonagenarians or centenarians) by the number of older persons (aged 65 or older) at the global level. Data were obtained from the UN’s World Population Prospects (2024). The chart created with power BI version 2.130.754.0.</p>
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14 pages, 350 KiB  
Review
Second Victims in Industries beyond Healthcare: A Scoping Review
by Andrea Conti, Alicia Sánchez-García, Daniele Ceriotti, Marta De Vito, Marco Farsoni, Bruno Tamburini, Sophia Russotto, Reinhard Strametz, Kris Vanhaecht, Deborah Seys, José Joaquín Mira and Massimiliano Panella
Healthcare 2024, 12(18), 1835; https://doi.org/10.3390/healthcare12181835 - 13 Sep 2024
Viewed by 209
Abstract
The second victim phenomenon (SVP) refers to workers negatively impacted by involvement in unanticipated adverse events or errors. While this phenomenon has been extensively studied in healthcare since its acknowledgment over 20 years ago, its presence and management in other high-risk industries have [...] Read more.
The second victim phenomenon (SVP) refers to workers negatively impacted by involvement in unanticipated adverse events or errors. While this phenomenon has been extensively studied in healthcare since its acknowledgment over 20 years ago, its presence and management in other high-risk industries have remained unclear. We conducted a scoping review aiming to map the SVP in non-healthcare industries, as well as to explore the available interventions or support programs addressed to help second victims (SVs). A total of 5818 unique records were identified and, after the screening process, 18 studies from eight sectors were included. All industries acknowledged the existence of the SVP, though many did not use a specific term for defining the SV. Similarities in psychological and emotional consequences were found across sectors. Support strategies varied, with the aviation sector implementing the most comprehensive programs. Self-care and peer support were the most reported interventions, while structured clinical support was not mentioned in any industry. Our review highlighted a lack of standardized terminology and industry-specific, evidence-based support interventions for the SVP outside of healthcare. Healthcare appears to be at the forefront of formally recognizing and addressing the SVP, despite traditionally learning from other high-reliability industries in safety practices. This presents opportunities for reciprocal learning and knowledge transfer between healthcare and other high-risk sectors. Full article
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Figure 1
<p>The modified version of the five-step model (adapted from Seys et al. [<a href="#B18-healthcare-12-01835" class="html-bibr">18</a>]).</p>
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<p>PRISMA flowchart.</p>
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16 pages, 5280 KiB  
Article
Simulation of Battery Thermal Management System for Large Maritime Electric Ship’s Battery Pack
by Fu Jia and Geesoo Lee
Energies 2024, 17(18), 4587; https://doi.org/10.3390/en17184587 - 12 Sep 2024
Viewed by 309
Abstract
In recent years, large power batteries have been widely used not only in automobiles and other vehicles but also in maritime vessels. The thermal uniformity of large marine battery packs significantly affects the performance, safety, and longevity of the electric ship. As a [...] Read more.
In recent years, large power batteries have been widely used not only in automobiles and other vehicles but also in maritime vessels. The thermal uniformity of large marine battery packs significantly affects the performance, safety, and longevity of the electric ship. As a result, the thermal management of large power batteries has become a crucial technical challenge with traditional battery management system (BMS) that cannot effectively solve the battery heating problem caused by electrochemical reactions and joule heating during operation. To address this gap, a battery thermal management system (BTMS) has been newly designed. This article presents the design of a large marine battery pack, which features a liquid cooling system integrated into both the bottom and side plates of each pack. The flow plate is constructed from five independent units, each connected by manifold structures at both ends. These connections ensure the formation of a stable and cohesive flow plate assembly. Although research on the BTMS is relatively advanced, there is a notable lack of studies examining the effects of liquid temperature, flow rate, and battery discharge rate on the temperature consistency and uniformity of large marine battery packs. This work seeks to design the cooling system for the battery pack and analyzes the impact of the temperature, flow rate, and battery discharge rate of the liquid fluid on the consistency and uniformity of the battery pack temperature on the overall structure of the battery pack. It was found that, in low discharge conditions, there was good temperature consistency between the battery packs and between the different batteries within the battery pack, and the temperature difference did not exceed 1 °C. However, under high discharge rates, a C-rate of 4C, there might have been a decrease in temperature consistency; the temperature rise rate even exceeded 50% compared to when the discharge rate was low. The flow rate in the liquid flow characteristics had little effect on the temperature consistency between the batteries and the temperature uniformity on the battery surface, and the temperature fluctuation was maintained within 1 °C. Conversely, the liquid flow temperature had little effect on the temperature distribution between the batteries, but it caused discrepancies in the surface temperature of the batteries. In addition, the liquid flow temperature could cause the overall temperature of the battery to increase or decrease, which also occurs under different discharge rates. Full article
(This article belongs to the Special Issue Battery Thermal Management)
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<p>Yara Birkeland, the first fully electric and autonomous container ship [<a href="#B3-energies-17-04587" class="html-bibr">3</a>].</p>
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<p>Schematic diagram of electric propulsion system.</p>
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<p>Schematic diagram of battery pack structure.</p>
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<p>Schematic diagram of the flow plate of a battery pack.</p>
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<p>Decomposition diagram of battery pack calculation domain.</p>
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<p>Computational grid system and overall temperature contour.</p>
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<p>Grid dependency test.</p>
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<p>Distribution of sampling points on the battery cell surface.</p>
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<p>Battery cell number index for module.</p>
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<p>Bar chart of surface center temperature for different groups of batteries. (<b>a</b>) Bar chart of surface center temperature for Group 1 (°C); (<b>b</b>) Bar chart of surface center temperature for Group 2 (°C); (<b>c</b>) Bar chart of surface center temperature for Group 3 (°C); (<b>d</b>) Bar chart of surface center temperature for Group 4 (°C); (<b>e</b>) Bar chart of surface center temperature for Group 5 (°C).</p>
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<p>Battery cell center temperature of different battery groups.</p>
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<p>The temperature distributions of the 3 groups.</p>
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<p>The temperatures distributions along the vertical direction on the battery surface (<b>a</b>) group 1; (<b>b</b>) group 3; (<b>c</b>) group 5.</p>
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<p>Schematic diagram of thermal conductivity process.</p>
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<p>Central temperature curve of battery group for varying flow rate.</p>
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<p>Temperature curve at the center of the battery group.</p>
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<p>Central temperature curve of battery group.</p>
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13 pages, 12554 KiB  
Article
Wettability Behaviour of Metal Surfaces after Sequential Nanosecond and Picosecond Laser Texturing
by Yin Tang, Zheng Fang, Yang Fei, Shuai Wang, Walter Perrie, Stuart Edwardson and Geoff Dearden
Micromachines 2024, 15(9), 1146; https://doi.org/10.3390/mi15091146 - 12 Sep 2024
Viewed by 369
Abstract
This study examines the wettability behaviour of 304 stainless steel (304SS) and Ti-6Al-4V (Ti64) surfaces after sequential nanosecond (ns) and picosecond (ps) laser texturing; in particular, how the multi-scale surface structures created influence the lifecycle of surface hydrophobicity. The effect of different post-process [...] Read more.
This study examines the wettability behaviour of 304 stainless steel (304SS) and Ti-6Al-4V (Ti64) surfaces after sequential nanosecond (ns) and picosecond (ps) laser texturing; in particular, how the multi-scale surface structures created influence the lifecycle of surface hydrophobicity. The effect of different post-process treatments is also examined. Surfaces were analysed using Scanning Electron Microscopy (SEM), a white light interferometer optical profiler, and Energy Dispersive X-ray (EDX) spectroscopy. Wettability was assessed through sessile drop contact angle (CA) measurements, conducted at regular intervals over periods of up to 12 months, while EDX scans monitored elemental chemical changes. The results show that sequential (ns + ps) laser processing produced multi-scale surface texture with laser-induced periodic surface structures (LIPSS). Compared to the ns laser case, the (ns + ps) laser processed surfaces transitioned more rapidly to a hydrophobic state and maintained this property for much longer, especially when the single post-process treatment was ultrasonic cleaning. Some interesting features in CA development over these extended timescales are revealed. For 304SS, hydrophobicity was reached in 1–2 days, with the CA then remaining in the range of 120 to 140° for up to 180 days; whereas the ns laser-processed surfaces took longer to reach hydrophobicity and only maintained the condition for up to 30 days. Similar results were found for the case of Ti64. The findings show that such multi-scale structured metal surfaces can offer relatively stable hydrophobic properties, the lifetime of which can be extended significantly through the appropriate selection of laser process parameters and post-process treatment. The addition of LIPSS appears to help extend the longevity of the hydrophobic property. In seeking to identify other factors influencing wettability, from our EDX results, we observed a significant and steady rate of increase in the carbon content at the surface over the study period. Full article
(This article belongs to the Special Issue Ultrafast Laser Micro- and Nanoprocessing, 2nd Edition)
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Figure 1
<p>Schematic of optical setup used for ps laser processing (Created with BioRender.com). The beam was attenuated by a λ/2 plate and a Glan-Laser Calcite Polarizer transmitting horizontal polarization. The beam passes through a diffraction-limited beam expander (Rodenstock; M = x3) and is then modulated by a reflective phase-only SLM and input to a galvo scanner after passing through a 4f optical system. An aperture allows the shaped zero-order light to pass through for laser processing.</p>
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<p>Schematic of the experimental process: laser process and surface property analysis methods (Created with BioRender.com). Four groups (1–4) of polished samples were processed with the ns laser to form the underlying micron-scale doubly periodic structure, while groups 3 and 4 were then also exposed to ps laser processing for LIPSS overlaying. For comparison, groups 1 and 3 were subjected to wettability tests twice a week, while groups 2 and 4 were measured for elemental concentration by EDX once a week. All samples were stored in ambient air during ageing.</p>
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<p>(Answer for question 2, reviewer 1). SEM images of ns laser processed 304SS and Ti64 surfaces. (<b>a</b>,<b>c</b>) are ×150 magnification, while (<b>b</b>,<b>d</b>) are ×1000 magnification.</p>
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<p>SEM image of LIPSS on 304SS and Ti64 surfaces: (<b>a</b>,<b>c</b>) ×1000 magnification and (<b>b</b>,<b>d</b>) ×5000 magnification.</p>
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<p>Surface topography 2D analyses, microscope images, and topography Fourier transform analyses of laser-textured functional surfaces before and after adding ps laser-generated LIPSS.</p>
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<p>Long-term wettability behaviour of ns laser ablated 304SS surfaces, for different post-process treatments: CA measured during the period up to 257 days after exposure.</p>
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<p>Wettability behaviour of ns laser processed Ti64 surfaces over a period of 141 days.</p>
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<p>Wettability behaviour of ns + ps laser processed 304SS and Ti64 surfaces over a period of 141 days.</p>
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<p>Comparison of time-dependent variation in carbon composition at the surface of samples processed by ns and (ns + ps) lasers, followed by ultrasonic cleaning: (<b>a</b>) 304SS and (<b>b</b>) Ti64.</p>
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<p>Comparison of time-dependent variation in oxygen composition at the surface of samples processed by ns and (ns + ps) lasers, followed by ultrasonic cleaning: (<b>a</b>) 304SS and (<b>b</b>) Ti64.</p>
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<p>EDX element-layered distribution map on ns (<b>a</b>) 304SS and (<b>d</b>) Ti64 and ns + ps (<b>b</b>) 304SS and (<b>e</b>) Ti64 laser processed surface structure ×500 magnification and (<b>c</b>) 304SS and (<b>f</b>) Ti64 ×1000 magnification Ns laser processed structure has obvious wider and stronger carbon absorption and oxidises around the peak of the structure compared to the ns + ps laser processed structure.</p>
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<p>SEM images of 304SS on (<b>a</b>) day 2 and (<b>b</b>) day 142. ns (<b>a-1</b>,<b>b-1</b>) and ns + ps (<b>a-2</b>,<b>b-2</b>) laser processed surface structure ×1000 magnification and (<b>a-3</b>,<b>b-3</b>) ×5000 magnification.</p>
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<p>SEM images of Ti64 on (<b>a</b>) day 2 and (<b>b</b>) day 142. ns (<b>a-1</b>,<b>b-1</b>) and ns + ps (<b>a-2</b>,<b>b-2</b>) laser-processed surface structure ×1000 magnification and (<b>a-3</b>,<b>b-3</b>) ×5000 magnification.</p>
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13 pages, 4217 KiB  
Article
Effect of Fatty Acids on Vegetable-Oil-Derived Sustainable Polyurethane Coatings for Controlled-Release Fertilizer
by Minhui Pang, Zirui Liu, Hongyan Li, Lina Liang and Lixia Li
Coatings 2024, 14(9), 1183; https://doi.org/10.3390/coatings14091183 - 12 Sep 2024
Viewed by 410
Abstract
Vegetable-oil-based polyurethane has become a promising sustainable candidate for controlled-release fertilizer based on green chemistry. The purpose of this study was to prepare a series of coatings from selective feedstocks including five vegetable oils with a high saturation degree, mono-unsaturation degree, or poly-unsaturation [...] Read more.
Vegetable-oil-based polyurethane has become a promising sustainable candidate for controlled-release fertilizer based on green chemistry. The purpose of this study was to prepare a series of coatings from selective feedstocks including five vegetable oils with a high saturation degree, mono-unsaturation degree, or poly-unsaturation degree, considering that vegetable oil fatty acids played a key role in the synthesis of polyol and polyurethane. The effect of the type and proportion of fatty acids on the physicochemical properties, microstructure, and macro-properties of vegetable-oil-derived polyols and their resulting coatings was characterized and discussed. The position and number of the hydroxy groups were determined by the type and proportion of fatty acid, and polyol from linseed oil with a high poly-unsaturation degree and three carbon–carbon double bonds had a high hydroxyl value and functionality, whereas polyol from palm oil with a high saturation degree possessed the lowest hydroxyl value and functionality. The resultant coating from linseed-oil-based polyol had a good cross-linking density, and the nitrogen release longevity of coated urea was 56 days at a coating percentage of 3%, and its nitrogen use efficiency was increased by 27.15% compared with conventional urea. Although the palm-oil-based coating had good hydrophobicity, its coated urea was not ideal. Overall, this study has enriched theories of bio-based polyurethane coatings for controlled-release fertilizers; using vegetable oil with a poly-unsaturation degree, it is easy to obtain an excellent coating for controlled-release fertilizer, and this will help provide economic and environmental benefits. Full article
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<p>Reaction diagram of the VOPs and their coatings.</p>
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<p>ATR-FTIR (<b>a</b>,<b>b</b>) and <sup>1</sup>H NMR (<b>c</b>,<b>d</b>) spectra of VOs and their polyols, respectively.</p>
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<p>ATR-FTIR (<b>a</b>) and XPS (<b>b</b>) spectra of coatings; XPS C1s (<b>c</b>–<b>e</b>) and O1s (<b>f</b>–<b>h</b>) fitting curves of PPU, RPU, and LPU, respectively.</p>
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<p>SEM and AFM images of PPU, RPU, and LPU coatings and films. SEM surface (<b>A1</b>–<b>A3</b>) and cross sections (<b>B1</b>–<b>B3</b>); AFM (<b>C1</b>,<b>D1</b>), (<b>C2</b>,<b>D2</b>), and (<b>C3</b>,<b>D3</b>), respectively.</p>
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<p>TG (<b>a</b>)/DTG (<b>b</b>) and WCAs (<b>c</b>) of coatings, and nitrogen release behaviors (<b>d</b>) of their coated urea.</p>
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<p>The results of the pot experiment. Picture of Chinese cabbage after growth for 45 days (<b>a</b>); effect of different treatments on fresh weight and dry weight (<b>b</b>), plant height (<b>c</b>), and nitrogen use efficiency (<b>d</b>) of Chinese cabbage. Various lowercase letters (a and b) demonstrate notable differences between the treatments (<span class="html-italic">p</span> &lt; 0.05).</p>
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16 pages, 338 KiB  
Review
Multifactorial Contributors to the Longevity of Dental Restorations: An Integrated Review of Related Factors
by Maria Jacinta Moraes Coelho Santos, Elham Zare, Peter McDermott and Gildo Coelho Santos Junior
Dent. J. 2024, 12(9), 291; https://doi.org/10.3390/dj12090291 - 12 Sep 2024
Viewed by 663
Abstract
Purpose: This integrated review aims to identify and analyze the multifactorial contributors to the longevity of direct restorations, focusing on tooth-, patient-, and dentist-related factors. Materials and Methods: A search of the literature was performed using an electronic database, PubMed/Medline, Web of Science, [...] Read more.
Purpose: This integrated review aims to identify and analyze the multifactorial contributors to the longevity of direct restorations, focusing on tooth-, patient-, and dentist-related factors. Materials and Methods: A search of the literature was performed using an electronic database, PubMed/Medline, Web of Science, and Scopus, on papers published between 1980 and 2024. The titles and abstracts of papers that evaluated aspects categorized into tooth-related, patient-related, and dentist-related factors influencing restoration failure were selected and screened. Full-text assessments were conducted, and the extracted data were compiled, summarized, and synthesized. The reference lists of the collected papers were also screened, and relevant citations were included in this review. Data were gathered from clinical and laboratorial studies, systematic reviews, and meta-analyses to provide a comprehensive understanding of restoration longevity. Results: Among the tooth-related factors, multiple-surface restorations, deep margins, tooth location, and tooth vitality significantly impact restoration survival. Patient-related factors such as medical conditions, risk predictors of caries, age, sex, parafunctional habits, smoking, periodontal health, number of restorations, and socioeconomic status all play crucial roles. Regarding dentist-related factors, the decision-making process, age, experience, and dentist manual dexterity are vital aspects. Furthermore, the technique used, including isolation methods for moisture control, as well as the type of dental practice (large group vs. small practice), notably influenced the restoration survival. Conclusions: The longevity of dental restorations is influenced by a complex interplay of tooth-related, patient-related, and dentist-related factors. Strategies to improve restoration outcomes should consider all these multifactorial contributors. Continuing professional education, diligent patient guidance on the factors that influence restoration survival, careful material selection and restorative technique, and tailored individual treatment are crucial factors to reduce failure rates and improve the lifespan of restorations. Full article
(This article belongs to the Special Issue Feature Review Papers in Dentistry)
14 pages, 7761 KiB  
Article
Lethal and Sub-Lethal Effects of Spirotetramat on Red Spider Mite, Tetranychus macfarlanei Baker and Pritchard (Acari: Tetranychidae)
by Farhana Afrose Swarna, Tasfia Hayder, Shreema Mandal Barsa, Powlomee Mondal, Tetsuo Gotoh and Mohammad Shaef Ullah
Arthropoda 2024, 2(3), 212-225; https://doi.org/10.3390/arthropoda2030016 - 12 Sep 2024
Viewed by 442
Abstract
The red spider mite, Tetranychus macfarlanei, is a serious pest of many cultivated crops in Bangladesh and other East-Asian and South-East Asian countries, in the Afrotropical, Oriental, and Palearctic regions. Sublethal concentration of pesticides, such as LC15 and LC30 (the [...] Read more.
The red spider mite, Tetranychus macfarlanei, is a serious pest of many cultivated crops in Bangladesh and other East-Asian and South-East Asian countries, in the Afrotropical, Oriental, and Palearctic regions. Sublethal concentration of pesticides, such as LC15 and LC30 (the concentrations that result in 15 and 30 percent lethality, respectively) impact reproduction, behavior, development, and physiology. This study assessed the effects of different concentrations of spirotetramat, an insecticide that disrupts lipid production, on the biological traits of T. macfarlanei. The LC15, LC30, LC50, and LC90 values were 2.16, 6.57, 20.54, and 332.81 mg·L−1, respectively. Sublethal concentrations (LC15 and LC30) slightly reduced female fecundity but did not significantly affect development duration, pre-oviposition, oviposition period, or longevity compared to the untreated control group. Life table parameters differed between the treated and control groups, with significant reductions in the intrinsic rate of increase (r), the net reproductive rate (R0), and the finite rate of increase (λ) for LC15 and LC30. LC15 and LC30 had negative effects on the intrinsic rate of increase for females. This study demonstrated that lower lethal concentrations of spirotetramat compromised survivability and negatively impacted the life-table parameters of subsequent generations of T. macfarlanei. These findings highlight the importance of sublethal effects in pest control, offering valuable insights for developing more effective and sustainable integrated pest management strategies. Full article
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<p>Age-stage specific survival rates (<span class="html-italic">s</span><sub>xj</sub>) of <span class="html-italic">Tetranychus macfarlanei</span> on different treatments of spirotetramat reared on bean plants at 25 °C under a 16L:8D photoperiod. The <span class="html-italic">s<sub>xj</sub></span> curves at different spirotetramat dosages indicate the probability of newly emerged <span class="html-italic">T. macfarlanei</span> surviving to age <span class="html-italic">x</span> and stage <span class="html-italic">j</span>. L denotes larva, PN denotes protonymph, and DN denotes deutonymph.</p>
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<p>Age-specific survivability (<span class="html-italic">l<sub>x</sub></span>), age-stage specific fecundity (<span class="html-italic">f<sub>x5</sub></span>), age-specific fecundity (<span class="html-italic">m<sub>x</sub></span>) and age-specific maternity (<span class="html-italic">l<sub>x</sub>m<sub>x</sub></span>) of <span class="html-italic">Tetranychus macfarlanei</span> on different treatments of spirotetramat reared on bean plants at 25 °C under a 16L:8D photoperiod.</p>
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<p>Age-stage life expectancy (<span class="html-italic">e<sub>xj</sub></span>) of <span class="html-italic">Tetranychus macfarlanei</span> on different treatments of spirotetramat reared on bean plants at 25 °C under a 16L:8D photoperiod. L denotes larva, PN denotes protonymph, and DN denotes deutonymph.</p>
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<p>Age-stage fecundity (<span class="html-italic">v<sub>xj</sub></span>) of <span class="html-italic">Tetranychus macfarlanei</span> on different treatments of spirotetramat reared on bean plants at 25 °C under a 16L:8D photoperiod. L denotes larva, PN denotes protonymph, and DN denotes deutonymph.</p>
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10 pages, 651 KiB  
Article
Phylo-Epigenetics in Phylogeny Analyses and Evolution
by Simeon Santourlidis
Genes 2024, 15(9), 1198; https://doi.org/10.3390/genes15091198 - 12 Sep 2024
Viewed by 280
Abstract
Long-standing, continuous blurring and controversies in the field of phylogenetic interspecies relations, associated with insufficient explanations for dynamics and variability of speeds of evolution in mammals, hint at a crucial missing link. It has been suggested that transgenerational epigenetic inheritance and the concealed [...] Read more.
Long-standing, continuous blurring and controversies in the field of phylogenetic interspecies relations, associated with insufficient explanations for dynamics and variability of speeds of evolution in mammals, hint at a crucial missing link. It has been suggested that transgenerational epigenetic inheritance and the concealed mechanisms behind play a distinct role in mammalian evolution. Here, a comprehensive sequence alignment approach in hominid species, i.e., Homo sapiens, Homo neanderthalensis, Denisovan human, Pan troglodytes, Pan paniscus, Gorilla gorilla, and Pongo pygmaeus, comprising conserved CpG islands of housekeeping genes, uncover evidence for a distinct variability of CpG dinucleotides. Applying solely these evolutionary consistent and inconsistent CpG sites in a classic phylogenetic analysis, calibrated by the divergence time point of the common chimpanzee (P. troglodytes) and the bonobo or pygmy chimpanzee (P. paniscus), a “phylo-epigenetic” tree has been generated, which precisely recapitulates branch points and branch lengths, i.e., divergence events and relations, as they have been broadly suggested in the current literature, based on comprehensive molecular phylogenomics and fossil records of many decades. It is suggested here that CpG dinucleotide changes at CpG islands are of superior importance for evolutionary developments. These changes are successfully inherited through the germ line, determining emerging methylation profiles, and they are a central component of transgenerational epigenetic inheritance. It is hidden in the DNA, what will happen on it later. Full article
(This article belongs to the Section Epigenomics)
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<p>(<b>A</b>) Representative excerpt of the alignment of assembled 24 5′ CpG-rich sequences (CpG islands) of conserved housekeeping genes in hominids. All single-nucleotide polymorphisms (SNPs) outside CpGs present in at least one of the seven species are highlighted in purple (approx. 4.8% of all possible, lined-up dinucleotide positions). All CpG dinucleotides largely preserved but affected by at least one nucleotide alteration in at least one of the species are highlighted in green (that is approx. 3.2% of all possible, lined up dinucleotide positions and 17% of all CpG positions). All CpG dinucleotides consistently preserved in all species are highlighted in light blue. CpGs are highlighted in red. (<b>B</b>) Representative excerpt of the corresponding A/T alignment in which only the CpG positions are depicted; i.e., all CpGs, including those consistent in all seven species were replaced by “A”, and those altered in at least in one of the species were replaced by a “T”. *: conserved nucleotide: change of purine by purine or pyrimidine by pyrimidine.</p>
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<p>Phylogenetic (<b>A</b>) and “phylo-epigenetic” (<b>B</b>) relations between 7 primate species based on genetic and epigenetic, respectively, differences in CpG islands of 24 conserved housekeeping genes. The phylogram of the left panel displays the phylogenetic relation of these primate species, based on single nucleotide changes including CpG sites, small deletions, and nucleotides gains. The phylogram of the right panel displays the “phylo-epigenetic” relation of these species, based on all consistently occurring CpG dinucleotides and all CpG dinucleotide differences in these CpG islands of conserved housekeeping genes.</p>
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13 pages, 1612 KiB  
Article
In Vivo Antioxidant Activity of Common Dietary Flavonoids: Insights from the Yeast Model Saccharomyces cerevisiae
by Graziana Assalve, Paola Lunetti, Vincenzo Zara and Alessandra Ferramosca
Antioxidants 2024, 13(9), 1103; https://doi.org/10.3390/antiox13091103 - 12 Sep 2024
Viewed by 430
Abstract
Background: Oxidative stress, associated with diseases and aging, underscores the therapeutic potential of natural antioxidants. Flavonoids, known for scavenging free radicals and modulating cell signaling, offer significant health benefits and contribute to longevity. To explore their in vivo effects, we investigated the antioxidant [...] Read more.
Background: Oxidative stress, associated with diseases and aging, underscores the therapeutic potential of natural antioxidants. Flavonoids, known for scavenging free radicals and modulating cell signaling, offer significant health benefits and contribute to longevity. To explore their in vivo effects, we investigated the antioxidant activity of quercetin, apigenin, luteolin, naringenin, and genistein, using Saccharomyces cerevisiae as a model organism. Methods: We performed viability assays to evaluate the effects of these compounds on cell growth, both in the presence and absence of H2O2. Additional assays, including spot assays, drug drop tests, and colony-forming unit assays, were also conducted. Results: Viability assays indicated that the tested compounds are non-toxic. H2O2 reduced yeast viability, but flavonoid-treated cells showed increased resistance, confirming their protective effect. Polyphenols scavenged intracellular reactive oxygen species (ROS) and protected cells from oxidative damage. Investigations into defense systems revealed that H2O2 induced catalase activity and oxidized glutathione accumulation, both of which were reduced by polyphenol treatment. Conclusions: The tested natural compounds enhance cell viability and reduce oxidative damage by scavenging ROS and modulating antioxidant defenses. These results suggest their potential as supplements and pave the way for further research. Full article
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<p>Sensitivity of <span class="html-italic">S. cerevisiae</span> cells to selected flavonoids. (<b>a</b>) Cells were grown in synthetic complete (SC) medium supplemented with glucose 2% in the presence of different concentrations of bioactive compounds, and the optical cell density (OD<sub>600</sub>) was obtained at 24 h. The relative growth (%) was expressed as normalized to untreated cells grown in the presence of 10 mM DMSO. (<b>b</b>) To perform the CFU assay, exponentially grown cells were spread onto glucose-supplemented SC plates containing 10 μM of each compound, the concentration at which cells showed the maximum percentage growth compared to the untreated control. Images were taken 24 h after cell seeding and were representative of three independent experiments. (<b>c</b>) The CFU assay data were expressed as a relative percentage of viability, setting the total number of cells in the DMSO control as 100%. Data are mean ± S.D. of three independent experiments.</p>
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<p>Effect of selected flavonoid treatment on <span class="html-italic">S. cerevisiae</span> cell growth. (<b>a</b>) Cells were grown with or without tested compounds (10 μM) in liquid glucose-supplemented SC medium containing 2 mM H<sub>2</sub>O<sub>2</sub>. Untreated cells grown in the absence of H<sub>2</sub>O<sub>2</sub> (DMSO) were used as a control. The optical density values at 600 nm refer to cell cultures after the indicated growth time. Growth curves data are expressed as the mean ± S.D. of three independent experiments. (<b>b</b>) Growth rates of yeast cells grown in the glucose-supplemented SC medium with H<sub>2</sub>O<sub>2</sub> in the presence or absence of the tested compounds were compared to growth rate of yeast cells grown without H<sub>2</sub>O<sub>2</sub>, which was set to 100%. (<b>c</b>) The doubling times of yeast cells grown in glucose-supplemented SC medium with H<sub>2</sub>O<sub>2</sub> in the presence or absence of the tested compounds were compared to the doubling time of yeast cells grown without H<sub>2</sub>O<sub>2</sub>, which was set to 100%. Growth rate data are the mean ± S.D. of three independent experiments, each performed in triplicate. * <span class="html-italic">p</span> &lt; 0.005.</p>
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<p>Antioxidant effect of selected flavonoids in <span class="html-italic">S. cerevisiae</span>. (<b>a</b>) Yeast cells were grown until the exponential phase in the presence of each tested compound (10 μM) or DMSO (10 mM). Then, cells were serially diluted, and spotted onto glucose-supplemented SC control plates, and (<b>b</b>) glucose-supplemented SC plates containing 2 mM H<sub>2</sub>O<sub>2</sub>. Plate images were taken at 48 h and are representative of three different experiments. (<b>c</b>) 1.5 × 10<sup>6</sup> cells were spread on a 120 × 120 mm square plate containing solid SC medium supplemented with glucose 2%. Sterile filters were added on the agar surface. Each filter was loaded with 5 μL of one of the tested compounds at the concentration of 10 μM and 5 μL of 2 mM H<sub>2</sub>O<sub>2</sub>. One filter was loaded with the same amount of DMSO without H<sub>2</sub>O<sub>2</sub>. Cell growth was evaluated after 48 h incubation at 30 °C by the halo around the filters. (<b>d</b>) Yeast cells were grown with 10 μM of each compound or DMSO for 24 h. Then, an appropriate dilution of the cells was spread onto glucose-supplemented SC plates containing 2 mM H<sub>2</sub>O<sub>2</sub> to perform CFU assays. Images were representative of three independent experiments. (<b>e</b>) CFU assay data were expressed as a relative percentage of viability, setting the total number of cells in DMSO control as 100%. Data are mean ± SD of three independent experiments. * <span class="html-italic">p</span> &lt; 0.005.</p>
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<p>Measurement of oxidative stress markers. (<b>a</b>) Quantification of intracellular ROS accumulated during treatment with H<sub>2</sub>O<sub>2</sub> in yeast cells pretreated with tested polyphenols. At least three independent experiments were performed in triplicate with <sup>#</sup> <span class="html-italic">p</span> value &lt; 0.001 when compared to DMSO control cells, * <span class="html-italic">p</span> value &lt; 0.001 when compared to H<sub>2</sub>O<sub>2</sub>-treated cells in the absence of bioactive compounds. (<b>b</b>) Quantification of protein carbonyl content accumulated during treatment with H<sub>2</sub>O<sub>2</sub> in yeast cells pretreated with tested polyphenols. Densitometry was used for quantitative analysis, with protein carbonyl content in DMSO control cells set to 100%. Data were taken from the same membrane. (<b>c</b>) Protein carbonyl content immunodetection with the corresponding control loading (α-tubulin).</p>
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<p>Measurement of antioxidant enzymatic and non-enzymatic defense systems. (<b>a</b>) Catalase activity in yeast cells pretreated with different polyphenols (10 µM) for 1 h, followed by incubation with 2 mM H<sub>2</sub>O<sub>2</sub> for another 1 h. (<b>b</b>) GSSG levels in yeast cells pretreated with different polyphenols (10 µM) for 1 h, followed by incubation with 2 mM H<sub>2</sub>O<sub>2</sub> for another 1 h. The data represent the mean of three independent experiments. <sup>#</sup> <span class="html-italic">p</span> value &lt; 0.001 when compared to DMSO control cells, * <span class="html-italic">p</span> value &lt; 0.001 when compared to H<sub>2</sub>O<sub>2</sub>-treated cells in absence of bioactive compounds.</p>
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12 pages, 7370 KiB  
Article
Impact of Surface Pretreatment on the Corrosion Resistance and Adhesion of Thin Film Coating on SS316L Bipolar Plates for Proton-Exchange Membrane Fuel Cell Applications
by Yasin Mehdizadeh Chellehbari, Abhay Gupta, Xianguo Li and Samaneh Shahgaldi
Molecules 2024, 29(18), 4319; https://doi.org/10.3390/molecules29184319 - 12 Sep 2024
Viewed by 374
Abstract
Coated SS316L is a potential alternative to the graphite bipolar plates (BPPs) used in proton-exchange membrane fuel cells (PEMFCs) owing to their low manufacturing cost and machinability. Due to their susceptibility to corrosion and passivation, which increases PEMFC ohmic resistance, protective and conductive [...] Read more.
Coated SS316L is a potential alternative to the graphite bipolar plates (BPPs) used in proton-exchange membrane fuel cells (PEMFCs) owing to their low manufacturing cost and machinability. Due to their susceptibility to corrosion and passivation, which increases PEMFC ohmic resistance, protective and conductive coatings on SS316L have been developed. However, coating adhesion is one of the challenges in the harsh acidic environment of PEMFCs, affecting the performance and durability of BPPs. This study compares mechanical polishing and the frequently adopted chemical etchants for SS316L: Adler’s, V2A, and Carpenter’s etchant with different etching durations and their impact on the wettability, adhesion, and corrosion resistance of a Nb-coated SS316L substrate. Contact angle measurements and laser microscopy revealed that all etching treatments increased the hydrophobicity and surface roughness of SS316L substrates. Ex situ potentiodynamic and potentiostatic polarization tests and interfacial contact resistance analysis revealed high corrosion resistance, interfacial conductivity, and adhesion of the Nb-coated SS316L substrate pretreated with V2A (7 min) and Adler’s (3 min) etchant. Increased hydrophobicity (contact angle = 101°) and surface roughness (Ra = 74 nm) achieved using V2A etchant led to the lowest corrosion rate (3.3 µA.cm−2) and interfacial resistance (15.4 mΩ.cm2). This study established pretreatment with V2A etchant (a solution of HNO3, HCl, and DI water (1:9:23 mole ratio)) as a promising approach for improving the longevity, electrochemical stability, and efficiency of the coated SS316L BPPs for PEMFC application. Full article
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<p>Comparison of the arithmetic mean roughness (Ra) and arithmetic mean height (Sa), line roughness profile, and morphology of the SS316L surfaces with different pretreatments.</p>
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<p>Comparison of surface morphology, mean surface roughness (Ra) and mean surface height (Sa), contact angle, and adhesion impact of the SS316L surfaces with different pretreatments.</p>
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<p>(<b>a</b>) Comparison of surface morphology for all coated samples. (<b>b</b>) X-ray diffractograms of uncoated and niobium (Nb)-coated SS316L samples.</p>
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<p>Tafel plots recorded before potentiostatic polarization in a 0.5 M H<sub>2</sub>SO<sub>4</sub> solution at 70 °C for all samples.</p>
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<p>The figure shows 6 h potentiostatic polarization at +0.8 V vs. reversible hydrogen electrode (RHE) in 0.5 M H<sub>2</sub>SO<sub>4</sub>, maintained at 70 °C for all samples.</p>
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<p>Interfacial contact resistance (ICR) plots (<b>a</b>) before corrosion analysis, (<b>b</b>) after corrosion analysis, and (<b>c</b>) at the compaction force of 1.5 MPa.</p>
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