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Search Results (263)

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13 pages, 1739 KiB  
Article
Using a Smartphone Application to Strengthen Pelvic Floor and Manage Symptomatology of Female Track and Field Athletes: A Randomized Controlled Study
by Natalia Romero-Franco, Elisa Bosch-Donate, Elena Vico-Moreno, Ángel Oliva-Pascual Vaca, Pau Martínez-Bueso, Jesús Molina-Mula and Juan Carlos Fernández-Domínguez
Appl. Sci. 2024, 14(24), 11927; https://doi.org/10.3390/app142411927 - 20 Dec 2024
Viewed by 252
Abstract
Despite the high prevalence of pelvic floor (PF) dysfunctions in female athletes, help-seeking is low due to embarrassment and disinformation. This study evaluated the effects of a 6-week exercise program guided by a specific app, with and without intravaginal biofeedback on the PF [...] Read more.
Despite the high prevalence of pelvic floor (PF) dysfunctions in female athletes, help-seeking is low due to embarrassment and disinformation. This study evaluated the effects of a 6-week exercise program guided by a specific app, with and without intravaginal biofeedback on the PF symptoms, strength, and sonographic measures of female athletes. Compliance with the program was evaluated. Thirty-nine athletes with PF symptoms used the app with different functionalities: experimental group 1 (n = 13) (EG1: exercises, PF information, and physiotherapists contact); experimental group 2 (n = 14) (EG2: exercises with biofeedback, PF information, and physiotherapists contact); and the control group (n = 12) (CG: PF information, and physiotherapists contact). Before and after the 6 weeks, PF symptoms, strength with the Oxford scale, and sonographic measures were evaluated. EG1 and EG2 improved strength (p = 0.028 and p = 0.001, respectively) and incontinence urinary symptoms (p = 0.041 and p = 0.002, respectively) over the baseline, without between-group differences (p > 0.05). No significant differences were observed in sonography (p > 0.05). Regarding compliance, 84.6 and 71.4% of athletes from EG1 and EG2 completed the program twice per week or more. A 6-week PF exercise program guided by the app improved PF symptoms and strength of female athletes and ensured high compliance with the program but was insufficient to improve sonography. Full article
(This article belongs to the Special Issue Advances in Sports Training and Biomechanics)
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<p>Flow diagram.</p>
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<p>Exercise program within the smartphone application (available for all athletes from experimental groups). PF, pelvic floor; s, seconds.</p>
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16 pages, 1075 KiB  
Review
International Nephrology Masterclass in Chronic Kidney Disease: Rationale, Summary, and Future Perspectives
by Francesco Pesce, Maria Vadalà, Edgar Almeida, Beatriz Fernandez, Denis Fouque, Jolanta Malyszko, Kai Schmidt-Ott, Peter Stenvinkel, David C. Wheeler, Samuel Seidu, Ana Cebrian, Nikolay Dimov, Marta Blanco Pardo, Ieva Ziedina, Nayaf Habashi, Joaquin Manrique, Sofia Homem De Melo Marques, Marco Antonio Vaca Gallardo, Larisa Shehaj, Milena Krasimirova Nikolova Vlahova, Luis Mendonça, Sara Ksiazek, Pierangelo Veltri, Giuseppe Pezzi, Gemma Patella, Greta Borelli, Michele Provenzano and Loreto Gesualdoadd Show full author list remove Hide full author list
Life 2024, 14(12), 1668; https://doi.org/10.3390/life14121668 - 17 Dec 2024
Viewed by 632
Abstract
Chronic kidney disease (CKD) is a progressive condition that affects more than 10% of the population worldwide, accounting for more than 843 million (M) individuals. The prevalence of CKD (844 M patients) is higher than that of diabetes mellitus (422 M patients), cancer [...] Read more.
Chronic kidney disease (CKD) is a progressive condition that affects more than 10% of the population worldwide, accounting for more than 843 million (M) individuals. The prevalence of CKD (844 M patients) is higher than that of diabetes mellitus (422 M patients), cancer (42 M patients), and HIV (37 M patients), but people are often less aware of it. Global expert groups predict reductions in the nephrology workforce in the next decade, with a declining interest in nephrology careers. Over time, KDIGO guidelines have also focused on topics related to the prevention or management of CKD patients in real-life settings. On these premises, a new educational program with international experts in the field of nephrology took place from November 2022 until March 2023 in Milan, Italy. This multinational masterclass provided an educational platform providing unbiased education on diagnosis and treatment by sharing the most recent research data on CKD and comorbidities, therefore creating a snowball effect to increase the implementation of best practices worldwide, using examples from ‘real-life’ patient outcomes. This paper provides an overview of the International Nephrology Masterclass (INM) concept, summarizing the key lectures and discussions, and giving an outline of future key developments. Full article
(This article belongs to the Special Issue Feature Papers in Medical Research: 3rd Edition)
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<p>Models to increase awareness of chronic kidney disease.</p>
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<p>Key messages of the discussed topic.</p>
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21 pages, 2734 KiB  
Article
Gut Microbiota: Association with Fiber Intake, Ultra-Processed Food Consumption, Sex, Body Mass Index, and Socioeconomic Status in Medical Students
by Laura Moreno-Altamirano, Karina Robles-Rivera, Hugo G. Castelán-Sánchez, Felipe Vaca-Paniagua, María del Carmen Iñarritu Pérez, Sandra Elvia Hernández-Valencia, Carlos Cruz-Casarrubias, Juan José García-García, Miguel Ruíz de la Cruz, Héctor Martínez-Gregorio, Clara Estela Díaz Velásquez, Guadalupe Soto-Estrada, Armando Navarro-Ocaña and Santiago Carrillo-Medina
Nutrients 2024, 16(23), 4241; https://doi.org/10.3390/nu16234241 - 9 Dec 2024
Viewed by 839
Abstract
The gut microbiota plays a vital role in various physical and physiological processes, including immune system regulation, neurotransmitter production, inflammatory response modulation, and the inhibition of pathogenic organisms. An imbalance in the microbial community, known as dysbiosis, has been associated with numerous health [...] Read more.
The gut microbiota plays a vital role in various physical and physiological processes, including immune system regulation, neurotransmitter production, inflammatory response modulation, and the inhibition of pathogenic organisms. An imbalance in the microbial community, known as dysbiosis, has been associated with numerous health issues. Biological influences, health behaviors, socioeconomic determinants, and nutritional status can disrupt this balance. Objective: To evaluate the differences in the gut microbiota composition in medical students according to fiber intake, ultra-processed food (UPF) consumption, sex, body mass index, and socioeconomic status. Methods: A cross-sectional study was conducted with 91 medical students, and 82 fecal samples were analyzed. Sociodemographic and dietary data were collected via questionnaires, UPF consumption was assessed using the NOVA classification, and trained nutritionists performed anthropometry. DNA extraction and 16S rRNA sequencing were performed for the microbial analysis. Bioinformatics and statistical tests included the Dunn and Kruskal–Wallis tests, a PCoA analysis, PERMANOVA, ANOVA, Spearman’s rank correlation, and alpha and beta diversity metrics. Results: Dietary fiber intake strongly influences gut microbiota composition. Lower fiber intake was associated with a higher prevalence of Parabacteroides and Muribaculaceae. Prevotella was more prevalent in individuals with lower UPF intake, while Phascolarctobacterium was prevalent in those with higher UPF consumption. Significant differences were associated with sex and UPF consumption but not BMI or SES. Women consumed more UPF, which correlated with distinct gut microbiota profiles. Conclusions: This study highlights the significant impact of diet, particularly fiber intake and UPF, on gut microbiota composition, emphasizing the importance of dietary habits in maintaining gut health. Full article
(This article belongs to the Section Prebiotics and Probiotics)
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<p>Composition of gut microbiota across different BMI and SES categories by sex. (<b>A</b>) Samples grouping according to sex and BMI. (<b>B</b>) Samples grouped according to SES and sex.</p>
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<p>Distribution of alpha diversity metrics (observed ASVs, Shannon, Simpson). (<b>A</b>) Sex, (<b>B</b>) BMI, (<b>C</b>) SES, (<b>D</b>) national consumption of UPF, (<b>E</b>) energy contribution of UPF by tertiles.</p>
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<p>Beta diversity (Atkinson distance). (<b>A</b>) Sex, (<b>B</b>) SES, (<b>C</b>) BMI, (<b>D</b>) national consumption of UPF, and (<b>E</b>) energy contribution of UPF by tertiles. The points on the graph represent the bacterial communities of each subject, with points closer together indicating more similar bacterial communities.</p>
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<p>Distribution of genera that were significantly enriched based on UPF consumption and fiber intake (<span class="html-italic">p</span>-values ≤ 0.01). (<b>A</b>) Genera enriched according to the national consumption of UPF. (<b>B</b>) Genera enriched according to the tertiles of UPF consumption. (<b>C</b>) Genera enriched in participants according to the meeting of the recommendation of fiber intake. (<b>D</b>) Genera enriched in participants with a fiber intake according to tertiles.</p>
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<p>Spearman correlations between bacterial genera and UPF consumption and fiber intake. Asterisks indicate <span class="html-italic">p</span>-values &lt; 0.05. A positive Spearman correlation suggests that higher UPF consumption or fiber intake values are associated with a higher relative abundance of the taxa. Negative correlations indicate that higher values of UPF consumption or fiber intake are associated with a lower relative abundance of the taxa.</p>
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31 pages, 3640 KiB  
Review
Helicobacter pylori: Routes of Infection, Antimicrobial Resistance, and Alternative Therapies as a Means to Develop Infection Control
by Ayman Elbehiry, Adil Abalkhail, Nuha Anajirih, Fahad Alkhamisi, Mohammed Aldamegh, Abdullah Alramzi, Riyad AlShaqi, Naif Alotaibi, Abdullah Aljuaid, Hilal Alzahrani, Feras Alzaben, Mohammed Rawway, Mai Ibrahem, Moustafa H. Abdelsalam, Nermin I. Rizk, Mohamed E. A. Mostafa, Moneef Rohail Alfaqir, Husam M. Edrees and Mubarak Alqahtani
Diseases 2024, 12(12), 311; https://doi.org/10.3390/diseases12120311 - 3 Dec 2024
Viewed by 1255
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative, spiral-shaped bacterium that colonizes the gastric epithelium and is associated with a range of gastrointestinal disorders, exhibiting a global prevalence of approximately 50%. Despite the availability of treatment options, H. pylori frequently reemerges and [...] Read more.
Helicobacter pylori (H. pylori) is a Gram-negative, spiral-shaped bacterium that colonizes the gastric epithelium and is associated with a range of gastrointestinal disorders, exhibiting a global prevalence of approximately 50%. Despite the availability of treatment options, H. pylori frequently reemerges and demonstrates increasing antibiotic resistance, which diminishes the efficacy of conventional therapies. Consequently, it is imperative to explore non-antibiotic treatment alternatives to mitigate the inappropriate use of antibiotics. This review examines H. pylori infection, encompassing transmission pathways, treatment modalities, antibiotic resistance, and eradication strategies. Additionally, it discusses alternative therapeutic approaches such as probiotics, anti-biofilm agents, phytotherapy, phototherapy, phage therapy, lactoferrin therapy, and vaccine development. These strategies aim to reduce antimicrobial resistance and enhance treatment outcomes for H. pylori infections. While alternative therapies can maintain low bacterial levels, they do not achieve complete eradication of H. pylori. These therapies are designed to bolster the immune response, minimize side effects, and provide gastroprotective benefits, rendering them suitable for adjunctive use alongside conventional treatments. Probiotics may serve as adjunctive therapy for H. pylori; however, their effectiveness as a monotherapy is limited. Photodynamic and phage therapies exhibit potential in targeting H. pylori infections, including those caused by drug-resistant strains, without the use of antibiotics. The development of a reliable vaccine is also critical for the eradication of H. pylori. This review identifies candidate antigens such as VacA, CagA, and HspA, along with various vaccine formulations, including vector-based and subunit vaccines. Some vaccines have demonstrated efficacy in clinical trials, while others have shown robust immune protection in preclinical studies. Nevertheless, each of the aforementioned alternative therapies requires thorough preclinical and clinical evaluation to ascertain their efficacy, side effects, cost-effectiveness, and patient compliance. Full article
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<p>Flow chart explaining the review process for manuscripts that have been screened.</p>
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<p>The pathways through which <span class="html-italic">H. pylori</span> is transmitted. Person-to-person transmission occurs among children, the elderly, healthcare workers, and individuals living in developing countries. The bacterium can spread through oral–oral, fecal–oral, or gastric–oral routes, as well as through fecal shedding that contaminates food or water sources. Oral–oral transmission may occur when sharing food utensils or between mothers and their newborns. Additionally, <span class="html-italic">H. pylori</span> can be transmitted to animals such as sheep, dogs, cats, and chickens through fecal shedding or direct fecal–oral contact. Food and water sources contaminated with <span class="html-italic">H. pylori</span> can also directly transmit the bacteria to susceptible individuals.</p>
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<p>The prevalence rates of multidrug-resistant <span class="html-italic">H. pylori</span> across various regions, including Asia (2001–2022), Africa (2007–2017), Europe (2013–2021), and America (2011–2022). The resistance rates to clarithromycin were found to be 37% in Asia, 15% in Africa, 22% in Europe, and 31.5% in America. For metronidazole, the resistance rates were 51% in Asia, 91% in Africa, 27% in Europe, and 42.1% in America. The resistance rates to levofloxacin were reported as 19% in Asia, 14% in Africa, 18% in Europe, and 37.6% in America. Lastly, amoxicillin resistance rates were recorded at 4% in Asia, 38% in Africa, 1% in Europe, and 2.6% in America.Resistance mechanisms primarily stem from mutations that alter pharmacological targets. Drug-resistant genotypes are linked to mutations affecting membrane permeability, biofilm formation, and efflux pumps [<a href="#B120-diseases-12-00311" class="html-bibr">120</a>,<a href="#B128-diseases-12-00311" class="html-bibr">128</a>]. Amoxicillin resistance mainly arises from changes in membrane permeability and mutations in the penicillin-binding protein gene [<a href="#B120-diseases-12-00311" class="html-bibr">120</a>]. <span class="html-italic">H. pylori</span> strains often resist clarithromycin due to point mutations in <span class="html-italic">23S rRNA</span>. A study at Peking University utilized next-generation sequencing to identify genetic factors enhancing resistance to levofloxacin and clarithromycin [<a href="#B129-diseases-12-00311" class="html-bibr">129</a>]. Key mutation sites for clarithromycin resistance include peptidyl transferases in the <span class="html-italic">23S rRNA</span>, with A2143G and A2142G being the most common. Mutations in the DNA gyrase (<span class="html-italic">gyrA</span>) gene (N87K, D91N, D91G) were linked to levofloxacin resistance [<a href="#B129-diseases-12-00311" class="html-bibr">129</a>]. Reduced drug influx due to structural changes in lipopolysaccharide (LPS) membranes also contributes to resistance. Mutations in the <span class="html-italic">rfaF</span> (LPS heptosyltransferase II) gene lead to deep, coarse LPS drug absorption [<a href="#B130-diseases-12-00311" class="html-bibr">130</a>] and causing slight resistance to chloramphenicol, along with cross-resistance to amoxicillin, tetracycline, and clarithromycin [<a href="#B131-diseases-12-00311" class="html-bibr">131</a>]. Increased expression of <span class="html-italic">tolC</span> homolog genes (<span class="html-italic">hefA</span>) in patients with gastrointestinal disorders in Iran [<a href="#B132-diseases-12-00311" class="html-bibr">132</a>] was linked to efflux pump induction, as shown by real-time PCR in metronidazole and clarithromycin-resistant bacteria. The multidrug-resistant phenotype was found in 9.5% of cases. A genome-wide analysis identified prevalent mutations, including A2143G in <span class="html-italic">23S rRNA</span> (63.1%) and alterations in the <span class="html-italic">rdxA</span> gene (85.5%).</p>
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<p>An overview of the biofilm formation process: (1) Attachment stage of biofilm formation involves reversible and irreversible processes. Reversible attachment occurs when planktonic cells adhere to surfaces via chemical interactions, aided by virulence factors like adhesins and pili, triggering biofilm formation and increasing microbial susceptibility to antimicrobials. (2) Growth (irreversible attachment) leads to microbial proliferation and colony establishment, enhancing adherence through transcriptional changes. This phase promotes substrate exchange, metabolic product distribution, and byproduct excretion. <span class="html-italic">H. pylori</span> secrete EPS, which lower biofilm cell susceptibility to host defenses and antimicrobials. (3) Development features an increasing extracellular matrix around microcolonies, driven by EPS production and quorum-sensing communication, both vital for resistance. Mature biofilms have high EPS content and interstitial spaces for nutrient, water, and planktonic cell movement. (4) Spreading occurs when detachment due to nutrient depletion prompts cells to seek new surfaces through erosion and sloughing.</p>
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<p>A range of alternative therapeutic approaches has been developed to combat the antimicrobial resistance exhibited by <span class="html-italic">H. pylori</span>. Probiotic therapy employs non-immune mechanisms to counteract <span class="html-italic">H. pylori</span> by competing for attachment sites, inhibiting the expression of virulence genes, and inducing cell death. Additionally, it reduces inflammatory mediators and regulates anti-inflammatory cytokines through immune mechanisms. Photodynamic therapy effectively eradicates <span class="html-italic">H. pylori</span> by generating ROS using a light source in conjunction with a photosensitizer. Phage therapy involves the production of progeny particles from bacteriophages that lyse host cells. The development of vaccines utilizing virulence antigens is crucial for reducing colonization and eradicating <span class="html-italic">H. pylori</span>. Phytotherapy can inhibit urease activity, prevent bacterial adhesion, and enhance membrane permeation against <span class="html-italic">H. pylori</span> infection. Lactoferrin therapy sequesters iron, interacts with lipopolysaccharides and lipoteichoic acids, modulates serine protease activity, and engages with peptidoglycan, ultimately leading to the collapse of the cellular wall.</p>
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15 pages, 3041 KiB  
Article
Economic Impact of the Application of the ETS to European Ports: Analysis of Different Scenarios
by Javier Vaca-Cabrero, Nicoletta González-Cancelas, Alberto Camarero-Orive, María Magdalena Esteban-Infantes Corral and Stefano Ricci
Sustainability 2024, 16(23), 10433; https://doi.org/10.3390/su162310433 - 28 Nov 2024
Viewed by 584
Abstract
The fight against climate change is one of the main global challenges of our time, and the European Union (EU) seeks to achieve climate neutrality and energy transition for the continent by 2050 through various policies. This research studies the economic implications of [...] Read more.
The fight against climate change is one of the main global challenges of our time, and the European Union (EU) seeks to achieve climate neutrality and energy transition for the continent by 2050 through various policies. This research studies the economic implications of the EU Emissions Trading System (ETS) on European ports. By analysing various maritime scenarios, the study assesses how the ETS influences shipping routes, port competitiveness, and overall economic activity. A key finding is that the ETS imposes significant additional costs on shipping companies, which could lead to adjustments in routes and a shift in cargo volumes to ports in regions with less stringent environmental regulations. This could result in job losses in European port communities and reduce the competitiveness of European ports. In addition, the potential for carbon leakage, where shipping activities are simply relocated to regions with fewer emission controls, is explored. Full article
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<p>Work flow. Source: own elaboration.</p>
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<p>Ishikawa diagram. Source: own elaboration.</p>
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<p>Impact of ETS application by dimension. Source: own elaboration.</p>
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<p>Maersk Chicago vessel GPS position. Source: own elaboration, data: SBC.</p>
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<p>Cost difference in scenario comparison 1. Source: own elaboration.</p>
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<p>Cost difference in scenario comparison 2. Source: own elaboration.</p>
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<p>Cost difference in scenario comparison 3. Source: own elaboration.</p>
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7 pages, 924 KiB  
Article
Effect of Trematode Metacercarial Infection on Walking in Larval Salamanders in the Southern Appalachian Mountains, USA
by Carlos Camp, Alexia Vaca-Nava and Addison Bowen
Parasitologia 2024, 4(4), 375-381; https://doi.org/10.3390/parasitologia4040033 - 26 Nov 2024
Viewed by 256
Abstract
According to the Host Manipulation Hypothesis, parasites modify the phenotype of their host to enhance host–host transmission and thereby increase fitness. Metacercarial infection of some amphibians changes host behavior, including locomotion, and thereby enhances predation by the definitive host. To further test this [...] Read more.
According to the Host Manipulation Hypothesis, parasites modify the phenotype of their host to enhance host–host transmission and thereby increase fitness. Metacercarial infection of some amphibians changes host behavior, including locomotion, and thereby enhances predation by the definitive host. To further test this hypothesis, it is first necessary to determine whether a parasite actually modifies a host’s phenotype. In the southern Appalachian Mountains of the US, metacercariae of the trematode Metagonimoides oregonensis (Price, 1931) encyst in the musculature of its second intermediate host, the salamander Desmognathus amphileucus Bishop, 1941. Metacercarial infections of musculature in fish negatively affect host swimming performance. Therefore, we tested the hypothesis that infection by M. oregonensis affects walking in the aquatic larvae of D. amphileucus. We compared this mode of locomotion between infected and uninfected larvae by placing them in 1 m troughs of water and allowing them to wander freely until they stopped. Non-parametric (Kaplan–Meier) survival analysis determined that infected salamanders stopped significantly sooner than uninfected ones. Because infected salamanders move less, the presence of this parasite may contribute to genetic divergence in these salamanders by slowing dispersal and concomitant gene flow. Our results suggest that macroparasites can potentially modify a host’s behavior with biological consequences beyond enhancement of parasite transmission. Full article
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<p>Ventral view of a larval <span class="html-italic">Desmognathus amphileucus</span> under magnification by a dissecting microscope, showing infection by metacercariae of <span class="html-italic">Metagonimoides oregonensis</span>.</p>
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<p>Cumulative survival (probability over time) plot generated by survival analysis comparing time spent moving by larval <span class="html-italic">Desmognathus amphileucus</span> that were infected with metacercariae of <span class="html-italic">Metagonimoides oregonensis</span> to uninfected larval <span class="html-italic">D. amphileucus</span>.</p>
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26 pages, 4366 KiB  
Article
Green Synthesis of Silver Oxide Nanoparticles from Mauritia flexuosa Fruit Extract: Characterization and Bioactivity Assessment
by Johana Zúñiga-Miranda, David Vaca-Vega, Karla Vizuete, Saskya E. Carrera-Pacheco, Rebeca Gonzalez-Pastor, Jorge Heredia-Moya, Arianna Mayorga-Ramos, Carlos Barba-Ostria, Elena Coyago-Cruz, Alexis Debut and Linda P. Guamán
Nanomaterials 2024, 14(23), 1875; https://doi.org/10.3390/nano14231875 - 22 Nov 2024
Viewed by 719
Abstract
The increasing prevalence of multidrug-resistant (MDR) pathogens, persistent biofilms, oxidative stress, and cancerous cell proliferation poses significant challenges in healthcare and environmental settings, highlighting the urgent need for innovative and sustainable therapeutic solutions. The exploration of nanotechnology, particularly the use of green-synthesized nanoparticles, [...] Read more.
The increasing prevalence of multidrug-resistant (MDR) pathogens, persistent biofilms, oxidative stress, and cancerous cell proliferation poses significant challenges in healthcare and environmental settings, highlighting the urgent need for innovative and sustainable therapeutic solutions. The exploration of nanotechnology, particularly the use of green-synthesized nanoparticles, offers a promising avenue to address these complex biological challenges due to their multifunctional properties and biocompatibility. Utilizing a green synthesis approach, Mauritia flexuosa Mf-Ag2ONPs were synthesized and characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy coupled with scanning electron microscopy (EDS-SEM), UV-Vis spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The Mf-Ag2ONPs exhibited potent antibacterial effects against both non-resistant and MDR bacterial strains, with minimum inhibitory concentrations (MICs) ranging from 11.25 to 45 µg/mL. Mf-Ag2ONPs also demonstrated significant antifungal efficacy, particularly against Candida glabrata, with an MIC of 5.63 µg/mL. Moreover, the nanoparticles showed strong biofilm inhibition capabilities and substantial antioxidant properties, underscoring their potential to combat oxidative stress. Additionally, Mf-Ag2ONPs exhibited pronounced anticancer properties against various cancer cell lines, displaying low IC50 values across various cancer cell lines while maintaining minimal hemolytic activity at therapeutic concentrations. These findings suggest that Mf-Ag2ONPs synthesized via an eco-friendly approach offer a promising alternative for biomedical applications, including antimicrobial, antifungal, antioxidant, and anticancer therapies, warranting further in vivo studies to fully exploit their therapeutic potential. Full article
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<p>(<b>a</b>) UV-Vis spectrum of the nanoparticle dispersion and (<b>b</b>) color change in the synthesis process.</p>
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<p>DLS: hydrodynamic diameter of Mf-Ag<sub>2</sub>ONPs.</p>
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<p>XRD diffractogram of Mf-Ag<sub>2</sub>ONPs.</p>
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<p>TEM image of synthesized Mf-Ag<sub>2</sub>ONPs.</p>
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<p>(<b>a</b>) EDS analysis and (<b>b</b>) SEM analysis of Mf-Ag<sub>2</sub>ONPs.</p>
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<p>FTIR spectra of (<b>a</b>) extract of <span class="html-italic">M. flexuosa</span> and (<b>b</b>) Mf-Ag<sub>2</sub>ONPs.</p>
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<p>Percentage of biofilm inhibition of (<b>a</b>) <span class="html-italic">S. aureus</span> ATCC 25923, (<b>b</b>) <span class="html-italic">P. aeruginosa</span> ATCC 9027, (<b>c</b>) <span class="html-italic">L. monocytogenes</span> ATCC 13932, and (<b>d</b>) <span class="html-italic">B. cepacia</span> ATCC 25416 after 24 h incubation with Mf-Ag<sub>2</sub>ONP at a 2.5–40—µg/mL concentration. Treatments at different concentrations were compared with a 50% theoretical inhibition control for statistical significance using a two-way ANOVA test. All the values are mean ± SD, <span class="html-italic">p</span>-value (*) &lt; 0.05, (**) &lt; 0.01, and (***) &lt; 0.001.</p>
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<p>Dose–response curves of Mf-Ag<sub>2</sub>ONPs (<b>a</b>) and Mf extract (<b>b</b>) against tumor and non-tumor cell lines after 72 h incubation.</p>
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10 pages, 2485 KiB  
Proceeding Paper
Analysis of Energy Requirements for Massive Integration of Electric Buses in Ambato City, Ecuador
by Paola Quintana, Angélica Vaca Yánez, Henry Acurio, Sebastián Villacrés and Verónica Guayanlema
Eng. Proc. 2024, 77(1), 12; https://doi.org/10.3390/engproc2024077012 - 18 Nov 2024
Viewed by 258
Abstract
Ecuador’s Energy Efficiency Law mandates that “as of 2030, all vehicles incorporated into urban public transport services must be electric”. This legal framework sets the stage for the country’s transition to electric mobility. This research examines the energy requirements for transitioning Ambato’s public [...] Read more.
Ecuador’s Energy Efficiency Law mandates that “as of 2030, all vehicles incorporated into urban public transport services must be electric”. This legal framework sets the stage for the country’s transition to electric mobility. This research examines the energy requirements for transitioning Ambato’s public bus fleet to electric vehicles, considering various technical and operational factors. The analysis evaluates the current fleet size, the expected lifespan of buses, daily operational hours, average speed, and the specific characteristics of the city’s public transport routes. Furthermore, this study delves into the technical aspects of energy consumption in electric public transport by calculating the driving force necessary to operate buses across different terrains and routes. Factors such as bus weight, passenger load, road gradient, and acceleration patterns are analyzed to assess their impact on energy consumption and vehicle range. Additionally, this study investigates the potential for regenerative braking and the necessary charging infrastructure, offering a comprehensive assessment of how these systems would function within Ambato. By forecasting future vehicle requirements and projecting growth in urban mobility, this study estimates the total energy demand for a fully electric public bus fleet. The potential for integrating renewable energy sources into the city’s grid is also explored, ensuring that the transition to electric mobility not only decreases reliance on fossil fuels but also supports cleaner energy sources. This research serves as a crucial step in understanding the infrastructure and policy changes required for the successful implementation of electric public transport in Ambato and similar Ecuadorian cities. Full article
(This article belongs to the Proceedings of The XXXII Conference on Electrical and Electronic Engineering)
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<p>Methodological diagram.</p>
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<p>Base Map of Ambato City (author’s own work).</p>
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<p>Density map of Public Transport Routes (author’s own work).</p>
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<p>Density map of Public Transport Routes.</p>
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10 pages, 1702 KiB  
Proceeding Paper
Optimal Sizing of Hybrid Generation Systems (Photovoltaic System and Energy Storage System) for Off-Grid Applications
by Jaime Guamangallo, Jefferson Porras, Carlos Quinatoa, Jimmy Vaca and Luis Chiza
Eng. Proc. 2024, 77(1), 24; https://doi.org/10.3390/engproc2024077024 - 18 Nov 2024
Viewed by 330
Abstract
This paper presents an optimal sizing strategy for a hybrid generation system combining photovoltaic (PV) and energy storage systems. To achieve this, the optimization problem is solved using the simplex method for linear programming, implemented through Python. The model considers test data on [...] Read more.
This paper presents an optimal sizing strategy for a hybrid generation system combining photovoltaic (PV) and energy storage systems. To achieve this, the optimization problem is solved using the simplex method for linear programming, implemented through Python. The model considers test data on electrical energy demand and solar irradiation, alongside battery operating conditions such as state of charge (SOC) and upper and lower charge limits as key decision variables. Conventional PV system sizing serves as a benchmark to assess the effectiveness of the optimization, with particular attention given to the computational resources required for problem solving.The results obtained from the optimization method demonstrate a substantial improvement in the utilization of energy resources, both from the photovoltaic system and the energy storage system. This approach enabled the design of an optimized system based on the proposed model, which was further refined using Matlab/Simulink. Full article
(This article belongs to the Proceedings of The XXXII Conference on Electrical and Electronic Engineering)
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<p>Typical schematic of a hybrid power generation system [<a href="#B13-engproc-77-00024" class="html-bibr">13</a>].</p>
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<p>Diagram of the proposed methodology.</p>
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<p>Load profile. Test data.</p>
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<p>Solar irradiation. Test data.</p>
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<p>Results obtained. Hybrid system optimization.</p>
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<p>Solar panel calculator. Adapted from [<a href="#B25-engproc-77-00024" class="html-bibr">25</a>].</p>
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16 pages, 4482 KiB  
Article
Dual Loading of Trans-Cinnamaldehyde and Either Paclitaxel or Curcumin in Chitosan Nanoparticles: Physicochemical Characterization and Biological Evaluation Against MDCK and HeLa Cells
by Cynthia L. Barrera-Martínez, Héctor I. Meléndez-Ortiz, Felipe Padilla-Vaca, Leonard I. Atanase, René D. Peralta-Rodríguez and Ioannis Liakos
Polymers 2024, 16(21), 3087; https://doi.org/10.3390/polym16213087 - 31 Oct 2024
Viewed by 812
Abstract
Biopolymer chitosan sub-micron particles (CSMPs) were prepared by the ionic gelation technique crosslinked with sodium tripolyphosphate co-loaded with trans-cinnamaldehyde (TCIN), and either curcumin (CUR) or paclitaxel (PTX). The size of the spherical CSMPs increased from 118 nm to 136 nm and 170 nm [...] Read more.
Biopolymer chitosan sub-micron particles (CSMPs) were prepared by the ionic gelation technique crosslinked with sodium tripolyphosphate co-loaded with trans-cinnamaldehyde (TCIN), and either curcumin (CUR) or paclitaxel (PTX). The size of the spherical CSMPs increased from 118 nm to 136 nm and 170 nm after the loading of TCIN and CUR, whereas the loading of PTX led to a slight decrease (114 nm). Polydispersity indexes of all the samples were smaller than 0.4, indicating monodisperse particles. Zeta potential values higher than +40 mV were determined, which is direct proof of the high stability of these nanoparticles. TCIN and PTX release studies in vitro, at pH 6.5 and 7.4, showed a pH dependence on the release rate with a higher value at pH 6.5. However, CUR was not released from CSMPs probably due to strong interactions with CS biopolymer chains. Cytotoxicity studies showed that the systems loaded with TCIN and PTX were more cytotoxic for HeLa cancer cells than for MDCK cells. Moreover, a synergistic effect against HeLa cells was observed for the TCIN-PTX-loaded CSMP samples. The Sensitivity Index indicated that the CSMPs loaded with TCIN have a prospective attraction to carry and release conventional or new chemotherapeutic drugs. This study demonstrates the in vitro efficiency of the obtained drug delivery system, but in vivo studies are necessary to confirm its potential for clinical applications. Full article
(This article belongs to the Section Polymer Networks)
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<p>Particle size distribution of TCIN-loaded CSMPs.</p>
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<p>Resonance structure of trans-cinnamaldehyde. Created with ChemSketch.</p>
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<p>SEM micrographs of (<b>a</b>) non-loaded, (<b>b</b>) TCIN-loaded, (<b>c</b>) TCIN-CUR-loaded, and (<b>d</b>) TCIN-PTX-loaded CSMPs.</p>
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<p>In vitro release tests at pH 6.5 (black symbols) and 7.4 (blue symbols). (<b>a</b>) TCIN-CUR-loaded and (<b>b</b>) TCIN-PTX-loaded CSMPs.</p>
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<p>Cell viability of (<b>a</b>) MDCK and (<b>b</b>) HeLa cells exposed at 24 h for CUR/DMSO, TCIN-loaded CSMPs, and TCIN-CUR-loaded CSMPs.</p>
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<p>Cell viability of (<b>a</b>) MDCK and (<b>b</b>) HeLa cell lines exposed during 24 h for the PTX/DMSO, TCIN-loaded CSMPs, and TCIN-PTX-loaded CSMPs.</p>
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<p>Light microscopy images of MDCK and HeLa cell lines exposed to CUR/DMSO and TCIN-CUR-loaded CSMPs for 24 h. Image taken with digital camera of 40× and 100× objectives.</p>
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<p>Light microscopy images of MDCK and HeLa cell lines exposed to PTX/DMSO and TCIN-PTX-loaded CSMPs for 24 h. Image taken with digital camera of 40× and 100× objectives.</p>
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<p>Viability (%) of HeLa cells exposed for 24 h to PTX, CUR, and TCIN in DMSO at concentrations from 400 to 4000 µM.</p>
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11 pages, 257 KiB  
Article
Association of Antibody Responses to Helicobacter pylori Proteins with Colorectal Adenoma and Colorectal Cancer
by Flavia Genua, Julia Butt, Harsha Ganesan, Tim Waterboer and David J. Hughes
Pathogens 2024, 13(10), 897; https://doi.org/10.3390/pathogens13100897 - 14 Oct 2024
Cited by 1 | Viewed by 982
Abstract
Helicobacter pylori (H. pylori) has been implicated in colorectal carcinogenesis. Here, the association of immune responses to bacterial exposure with advancing stages of colorectal neoplasia was assessed by multiplex serology. Immunoglobulin (Ig) A and G antibody responses to thirteen proteins of [...] Read more.
Helicobacter pylori (H. pylori) has been implicated in colorectal carcinogenesis. Here, the association of immune responses to bacterial exposure with advancing stages of colorectal neoplasia was assessed by multiplex serology. Immunoglobulin (Ig) A and G antibody responses to thirteen proteins of H. pylori were measured by a Luminex-based multiplex assay in plasma from patients with colorectal cancer (CRC, n = 25), advanced adenoma (n = 82), or small polyps (n = 85) and controls (n = 100). Multivariable logistic regression was used to assess the association of bacterial seropositivity with colorectal neoplasia. The threshold for overall seropositivity required subjects to be positive for at least 4 out of the 13 tested antigens. In a cohort subset with matched data (n = 34), H. pylori seropositivity was correlated with bacterial abundance in both neoplastic and matched normal tissue. While no association was found between H. pylori seropositivity and the presence of CRC, IgA seropositivity to CagA was associated with a decreased risk of advanced adenoma (odds ratio, OR = 0.48, 95% confidence intervals, CIs: 0.24–0.96). Regarding IgG, higher antibody responses to HpaA was associated with advanced adenoma occurrence (OR = 2.46, 95% CI: 1.00–6.01), while responses to HP0395, CagA and Catalase were associated with polyp development (OR = 2.65, 95%, CI: 1.31–5.36, OR = 1.83, 95% CI: 1.01–3.32, and OR = 2.16, CI: 1.09–4.29, respectively). Positive correlations were found between H. pylori abundance in the normal mucosa and levels of both the IgA and IgG antibody response to Catalase and VacA antigens (r = 0.48, p < 0.01; r = 0.37, p = 0.04; r = 0.51, p < 0.01; and r = 0.71, p = 0.04, respectively). Conversely, H. pylori abundance was negatively correlated with levels of IgA antibody response to HpaA and with IgG antibody response to HP0231 in the diseased tissue (r = −0.34, p = 0.04 and r = −0.41, p = 0.01, respectively). The association between levels of H. pylori antigens and colorectal neoplasia risk gradually decreased with the adenoma progression, implicating the early activation of the immune response at the polyp stage. Thus, the evaluation of antibody response to certain bacterial antigens may indicate the presence of early-stage colorectal neoplasia. Further studies are needed to clarify the role H. pylori or the immune response to its antigens may have in colorectal carcinogenesis stages. Full article
(This article belongs to the Section Bacterial Pathogens)
16 pages, 2668 KiB  
Article
Enhanced Yield of Methyl Ethyl Ketone through Levulinic Acid Decarboxylation in the AgNO3/K2S2O8 System: Mechanistic Insights and Characterization of Metallic Species
by Nydia I. Guzmán Barrera, Jérôme Peydecastaing, Jérôme Esvan, Joël Albet, Carlos Vaca-Garcia, Philippe Behra, Emeline Vedrenne and Sophie Thiébaud-Roux
Molecules 2024, 29(20), 4822; https://doi.org/10.3390/molecules29204822 - 11 Oct 2024
Viewed by 874
Abstract
Methyl ethyl ketone (MEK) is among the most extensively utilized solvents in various industrial applications. In this study, we present a highly efficient synthesis route for MEK via the decarboxylation of biomass-derived levulinic acid, using potassium persulfate (K2S2O8 [...] Read more.
Methyl ethyl ketone (MEK) is among the most extensively utilized solvents in various industrial applications. In this study, we present a highly efficient synthesis route for MEK via the decarboxylation of biomass-derived levulinic acid, using potassium persulfate (K2S2O8) and silver nitrate (AgNO3) as key reagents. The specific roles of AgNO3 and K2S2O8 were thoroughly investigated. Additional silver species, such as Ag2O and AgO, were also detected during the reaction. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses provided evidence of the evolution of solid phases throughout the reaction. Based on these findings, we propose a radical decarboxylation mechanism initiated by the generation of sulfate radicals (SO4•⁻) through the catalytic breakdown of K2S2O8 by AgNO3. This mechanistic understanding, combined with a parametric study, enabled us to achieve an unprecedented level of levulinic acid conversion (97.9%) and MEK yield (86.6%) with this system, surpassing all previously reported results in the literature. Full article
(This article belongs to the Special Issue Applied Chemistry in Europe 2024)
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<p>Decarboxylation of LA with 1 eq. of K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> in the absence of AgNO<sub>3</sub>. Experimental conditions: K<sub>2</sub>HPO<sub>4</sub>/KH<sub>2</sub>PO<sub>4</sub> (0.1/0.1 M), 100 °C.</p>
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<p>LA decarboxylation at different temperatures and reaction times (<b>a</b>) 100, (<b>b</b>) 60, and (<b>c</b>) 25 °C. Experimental conditions: AgNO<sub>3</sub>/K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> (1/1), KH<sub>2</sub>PO<sub>4</sub>/K<sub>2</sub>HPO<sub>4</sub> (0.1/0.1 M).</p>
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<p>XRD patterns for the solid phase (<b>a</b>) before and (<b>b</b>) after the reaction. Experimental conditions: AgNO<sub>3</sub>/K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> (1/1), KH<sub>2</sub>PO<sub>4</sub>/K<sub>2</sub>HPO<sub>4</sub> (0.2 M), 100 °C, 30 min.</p>
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<p>AgMNN Auger signals of the solid phase (<b>a</b>) before and (<b>b</b>) after levulinic acid decarboxylation.</p>
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<p>XRD patterns for the solid phase: (<b>a</b>) after M1 neutralization, (<b>b</b>) after the second cycle of the reaction, with the addition of K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>. Experimental conditions: AgNO<sub>3</sub>/K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> (1/1), KH<sub>2</sub>PO<sub>4</sub>/K<sub>2</sub>HPO<sub>4</sub> (0.1/0.1 M), 100 °C.</p>
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<p>AgMNN Auger signals for the solid phase: (<b>a</b>) after M1 neutralization, (<b>b</b>) after the second cycle of reaction. Experimental conditions: AgNO<sub>3</sub>/K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> (1/1), KH<sub>2</sub>PO<sub>4</sub>/K<sub>2</sub>HPO<sub>4</sub> (0.1/0.1 M), 100 °C, 30 min.</p>
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<p>Proposed mechanisms.</p>
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<p>AcOH production via MEK oxidation.</p>
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20 pages, 2054 KiB  
Review
Using Social Robotics to Identify Educational Behavior: A Survey
by Antonio J. Romero-C. de Vaca, Roberto Angel Melendez-Armenta and Hiram Ponce
Electronics 2024, 13(19), 3956; https://doi.org/10.3390/electronics13193956 - 8 Oct 2024
Viewed by 1740
Abstract
The advancement of social robots in recent years has opened a promising avenue for providing users with more accessible and personalized attention. These robots have been integrated into various aspects of human life, particularly in activities geared toward students, such as entertainment, education, [...] Read more.
The advancement of social robots in recent years has opened a promising avenue for providing users with more accessible and personalized attention. These robots have been integrated into various aspects of human life, particularly in activities geared toward students, such as entertainment, education, and companionship, with the assistance of artificial intelligence (AI). AI plays a crucial role in enhancing these experiences by enabling social and educational robots to interact and adapt intelligently to their environment. In social robotics, AI is used to develop systems capable of understanding human emotions and responding to them, thereby facilitating interaction and collaboration between humans and robots in social settings. This article aims to present a survey of the use of robots in education, highlighting the degree of integration of social robots in this field worldwide. It also explores the robotic technologies applied according to the students’ educational level. This study provides an overview of the technical literature in social robotics and behavior recognition systems applied to education at various educational levels, especially in recent years. Additionally, it reviews the range of social robots in the market involved in these activities. The objects of study, techniques, and tools used, as well as the resources and results, are described to offer a view of the current state of the reviewed areas and to contribute to future research. Full article
(This article belongs to the Special Issue New Advances in Human-Robot Collaboration)
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<p>Flowchart of the review conducted.</p>
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<p>Studies per continent.</p>
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<p>Studies per country.</p>
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<p>Documents per year included in the study.</p>
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<p>NAO was the most used social robot in this study.</p>
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16 pages, 1077 KiB  
Article
Molecular Properties of Virulence and Antibiotic Resistance of Pseudomonas aeruginosa Causing Clinically Critical Infections
by Eric Monroy-Pérez, Jennefer Paloma Herrera-Gabriel, Elizabeth Olvera-Navarro, Lorena Ugalde-Tecillo, Luis Rey García-Cortés, Moisés Moreno-Noguez, Héctor Martínez-Gregorio, Felipe Vaca-Paniagua and Gloria Luz Paniagua-Contreras
Pathogens 2024, 13(10), 868; https://doi.org/10.3390/pathogens13100868 - 3 Oct 2024
Cited by 1 | Viewed by 1167
Abstract
The increase in the number of hospital strains of hypervirulent and multidrug resistant (MDR) Pseudomonas aeruginosa is a major health problem that reduces medical treatment options and increases mortality. The molecular profiles of virulence and multidrug resistance of P. aeruginosa-associated hospital and [...] Read more.
The increase in the number of hospital strains of hypervirulent and multidrug resistant (MDR) Pseudomonas aeruginosa is a major health problem that reduces medical treatment options and increases mortality. The molecular profiles of virulence and multidrug resistance of P. aeruginosa-associated hospital and community infections in Mexico have been poorly studied. In this study, we analyzed the different molecular profiles associated with the virulence genotypes related to multidrug resistance and the genotypes of multidrug efflux pumps (mex) in P. aeruginosa causing clinically critical infections isolated from Mexican patients with community- and hospital-acquired infections. Susceptibility to 12 antibiotics was determined using the Kirby–Bauer method. The identification of P. aeruginosa and the detection of virulence and efflux pump system genes were performed using conventional PCR. All strains isolated from patients with hospital-acquired (n = 67) and community-acquired infections (n = 57) were multidrug resistant, mainly to beta-lactams (ampicillin [96.7%], carbenicillin [98.3%], cefalotin [97.5%], and cefotaxime [87%]), quinolones (norfloxacin [78.2%]), phenicols (chloramphenicol [91.9%]), nitrofurans (nitrofurantoin [70.9%]), aminoglycosides (gentamicin [75%]), and sulfonamide/trimethoprim (96.7%). Most strains (95.5%) isolated from patients with hospital- and community-acquired infections carried the adhesion (pilA) and biofilm formation (ndvB) genes. Outer membrane proteins (oprI and oprL) were present in 100% of cases, elastases (lasA and lasB) in 100% and 98.3%, respectively, alkaline protease (apr) and alginate (algD) in 99.1% and 97.5%, respectively, and chaperone (groEL) and epoxide hydrolase (cif) in 100% and 97.5%, respectively. Overall, 99.1% of the strains isolated from patients with hospital- and community-acquired infections carried the efflux pump system genes mexB and mexY, while 98.3% of the strains carried mexF and mexZ. These findings show a wide distribution of the virulome related to the genotypic and phenotypic profiles of antibiotic resistance and the origin of the strains isolated from patients with hospital- and community-acquired infections, demonstrating that these molecular mechanisms may play an important role in high-pathogenicity infections caused by P. aeruginosa. Full article
(This article belongs to the Special Issue Bacterial Infections: Surveillance, Prevention and Control)
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<p>Hierarchical clustering of <span class="html-italic">P. aeruginosa</span> strains. The heat map is segmented into five panels, upper: (1) total cladogram of virulence genotype (VG), multidrug efflux pump (MEX), and genotype and antibiotic resistance phenotype (ARP), left: (2) VG in the upper, (3) MEX in the middle, (4) ARP in the lower, and (5) diagnosis and strain origin in the bottom panel. The right panel (pink) shows the absolute detection frequency by virulence genotype, multidrug efflux pump (MEX) and antibiotic resistance phenotype. The presence of a gene is represented in red and the absence in grey. Antibiotics (AB) are shown in <a href="#sec4-pathogens-13-00868" class="html-sec">Section 4</a>. ARP (resistome). CF = Cephalothin, CB = Carbenicillin, SXT = Trimethoprim-sulfamethoxazole, AM = Ampicillin, CL = Chloramphenicol, CFX = Cefotaxime, NOF = Norfloxacin, GE = Gentamicin, NF = Nitrofurantoin, NET = Netilmicin, AK = Amikacin, and CPF = Ciprofloxacin. Antibiotic resistance is represented in yellow and susceptibility in blue.</p>
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17 pages, 887 KiB  
Article
Control Based on Nonlinear Estimators of Parametric Uncertainties Applied to an Agricultural Tractor Equipped with a Towed Implement System
by Cuauhtémoc Acosta Lúa, Claudia Verónica Vera Vaca, Joel Hinojosa-Dávalos and Claudia Carolina Vaca García
AgriEngineering 2024, 6(4), 3618-3634; https://doi.org/10.3390/agriengineering6040206 - 1 Oct 2024
Viewed by 674
Abstract
This article presents a nonlinear control strategy designed to address parametric uncertainties in an agricultural tractor system coupled to a towed implement. The controller ensures accurate tracking of lateral and yaw velocities relative to desired reference trajectories, even under the presence of parametric [...] Read more.
This article presents a nonlinear control strategy designed to address parametric uncertainties in an agricultural tractor system coupled to a towed implement. The controller ensures accurate tracking of lateral and yaw velocities relative to desired reference trajectories, even under the presence of parametric variations and external disturbances. The reference trajectories are derived from an “ideal” tractor model, excluding the effects of the towed implement. A High-Order Sliding Mode (HOSM) estimator is employed to provide an estimation of disturbances, which are subsequently mitigated by the controller to maintain system stability and precision. The effectiveness of the proposed control strategy is validated through Matlab-Simulink simulations, which include a double-step steer maneuver. This maneuver tests the system’s ability to handle abrupt steering changes, providing insight into the controller’s robustness and its capacity to ensure accurate trajectory tracking in demanding conditions. Full article
(This article belongs to the Section Agricultural Mechanization and Machinery)
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<p>Dynamic model of the Tractor-Implement system.</p>
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<p>Forces applied to Tractor-Implement system.</p>
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<p>Steering angle <math display="inline"><semantics> <msub> <mi>δ</mi> <mi>d</mi> </msub> </semantics></math>.</p>
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<p>(<b>a</b>) Tractor lateral velocity <math display="inline"><semantics> <msub> <mi>v</mi> <mrow> <mi>y</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </semantics></math> (black) and reference <math display="inline"><semantics> <msub> <mi>v</mi> <mrow> <mi>y</mi> <mo>,</mo> <mi>t</mi> <mo>,</mo> <mi>r</mi> <mi>e</mi> <mi>f</mi> </mrow> </msub> </semantics></math> (red); (<b>b</b>) Tracking error <math display="inline"><semantics> <mrow> <msub> <mi>e</mi> <mrow> <mi>v</mi> <mo>,</mo> <mi>y</mi> </mrow> </msub> <mo>=</mo> <msub> <mi>v</mi> <mrow> <mi>y</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>v</mi> <mrow> <mi>y</mi> <mo>,</mo> <mi>t</mi> <mo>,</mo> <mi>r</mi> <mi>e</mi> <mi>f</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>(<b>a</b>) Tractor Yaw rate <math display="inline"><semantics> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </semantics></math> (black) and reference <math display="inline"><semantics> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> <mo>,</mo> <mi>r</mi> <mi>e</mi> <mi>f</mi> </mrow> </msub> </semantics></math> (red); (<b>b</b>) Tracking error <math display="inline"><semantics> <mrow> <msub> <mi>e</mi> <mrow> <mi>ω</mi> <mo>,</mo> <mi>z</mi> </mrow> </msub> <mo>=</mo> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> <mo>,</mo> <mi>r</mi> <mi>e</mi> <mi>f</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>(<b>a</b>) AFS <math display="inline"><semantics> <msub> <mo>Δ</mo> <mrow> <mi>f</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </semantics></math>; (<b>b</b>) RTV <math display="inline"><semantics> <msub> <mi>M</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </semantics></math>.</p>
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<p>(<b>a</b>) Yaw rate of the implement <math display="inline"><semantics> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>i</mi> </mrow> </msub> </semantics></math>; (<b>b</b>) Difference between <math display="inline"><semantics> <mrow> <mi>θ</mi> <mo>=</mo> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>ω</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>i</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>(<b>a</b>) Tracking error <math display="inline"><semantics> <msub> <mi>e</mi> <mrow> <mi>y</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </semantics></math> (black) and estimation <math display="inline"><semantics> <msub> <mi>ξ</mi> <mrow> <mi>y</mi> <mo>,</mo> <mn>1</mn> </mrow> </msub> </semantics></math> (red); (<b>b</b>) Parameter estimation <math display="inline"><semantics> <msub> <mi>δ</mi> <mi>y</mi> </msub> </semantics></math> (black) and estimation <math display="inline"><semantics> <msub> <mi>ξ</mi> <mrow> <mi>y</mi> <mo>,</mo> <mn>2</mn> </mrow> </msub> </semantics></math> (cyan); (<b>c</b>) Error <math display="inline"><semantics> <mrow> <msub> <mi>ξ</mi> <mrow> <mi>y</mi> <mo>,</mo> <mn>1</mn> </mrow> </msub> <mo>−</mo> <msub> <mi>e</mi> <mrow> <mi>y</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>; (<b>d</b>) Error <math display="inline"><semantics> <mrow> <msub> <mi>ξ</mi> <mrow> <mi>y</mi> <mo>,</mo> <mn>2</mn> </mrow> </msub> <mo>−</mo> <msub> <mi>δ</mi> <mi>y</mi> </msub> </mrow> </semantics></math>.</p>
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<p>(<b>a</b>) Tracking error <math display="inline"><semantics> <msub> <mi>e</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </semantics></math> (black) and estimation <math display="inline"><semantics> <msub> <mi>ξ</mi> <mrow> <mi>z</mi> <mo>,</mo> <mn>1</mn> </mrow> </msub> </semantics></math> (red); (<b>b</b>) Parameter estimation <math display="inline"><semantics> <msub> <mi>δ</mi> <mi>z</mi> </msub> </semantics></math> (black) and estimation <math display="inline"><semantics> <msub> <mi>ξ</mi> <mrow> <mi>z</mi> <mo>,</mo> <mn>2</mn> </mrow> </msub> </semantics></math> (cyan); (<b>c</b>) Error <math display="inline"><semantics> <mrow> <msub> <mi>ξ</mi> <mrow> <mi>z</mi> <mo>,</mo> <mn>1</mn> </mrow> </msub> <mo>−</mo> <msub> <mi>e</mi> <mrow> <mi>z</mi> <mo>,</mo> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>; (<b>d</b>) Error <math display="inline"><semantics> <mrow> <msub> <mi>ξ</mi> <mrow> <mi>z</mi> <mo>,</mo> <mn>2</mn> </mrow> </msub> <mo>−</mo> <msub> <mi>δ</mi> <mi>z</mi> </msub> </mrow> </semantics></math>.</p>
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