Search Results (138)

Background and Objectives: This study aimed to assess the week-by-week predictive value of Acute:Chronic Workload Ratios (ACWRs) for non-contact injury risk in professional soccer players. Materials and Methods: A cohort of 40 elite players was monitored using GPS over two competitive seasons. Binomial logistic regression and ROC curve analyses were performed on ACWR metrics—including total distance, moderate-to high-speed running, sprinting, acceleration, and deceleration—during the four weeks prior to injury (W4 to W1). p-values were further adjusted for multiple comparisons using the false discovery rate (FDR) correction (q < 0.05). Results: Significant predictive models emerged mainly for ACWR metrics related to moderate-speed running (15–20 km/h), sprinting (>25 km/h), and acceleration/deceleration. The ACWR for 15–20 km/h (DSR15–20) demonstrated the highest predictive accuracy, particularly in Week 3 (AUC = 0.811, p = 0.004). Sprinting (DSR>25) was also significantly associated with injury occurrence across Weeks 1–4 (AUC = 0.709–0.755, p = 0.011–0.024). Acceleration (ACC) and deceleration (DEC) metrics showed significant associations prior to correction—ACC in Weeks 3–4 (AUC = 0.737–0.755, p = 0.020–0.026) and DEC in Weeks 3–4 (AUC = 0.720–0.741, p = 0.029–0.043)—but these associations did not retain significance following FDR adjustment (q = 0.052–0.086). In contrast, total distance (ACWR TD) and high-speed running (20–25 km/h) were weaker predictors, reaching only marginal or nonsignificant levels (e.g., Week 3, AUC = 0.675, p = 0.054). After FDR correction, only DSR15–20 and DSR>25 remained statistically significant (q < 0.05), confirming them as robust predictors of non-contact injury risk. Multivariable models adjusted for age and playing position confirmed these findings, with DSR15–20 and DSR>25 retaining their predictive value independent of confounding factors. Injury risk thresholds were established through Estimated Marginal Means (EMMs), defining the “Sweet Spot” and “Danger Zone” for each metric, whereas the “Low Load” zone was treated as exploratory. Conclusions: This weekly ACWR monitoring approach enables practical injury risk profiling, helping training staff optimize load management and minimize non-contact injury risk in elite soccer. Full article

Invasive group A streptococcal (iGAS) infections are increasingly recognized as a global public health concern, with a notable resurgence observed among pediatric populations in high-income countries following the relaxation of COVID-19-related restrictions. While the most commonly implicated emm types in invasive disease are emm1 and emm3, the global distribution of Streptococcus pyogenes strains is highly diverse, posing challenges for surveillance and vaccine development. We describe a 3-year-old boy with a femoral subperiosteal abscess, a rare clinical manifestation of iGAS, caused by an emm6.10 S. pyogenes strain. The diagnosis was confirmed by positive blood cultures and magnetic resonance imaging. Antibiotic therapy included intravenous ceftriaxone followed by oral amoxicillin, and then prolonged oral clindamycin was introduced due to the deep-seated nature of the infection. Molecular typing was performed by the national reference center as part of routine surveillance of invasive strains. This case emphasizes the importance of recognizing atypical clinical presentations of iGAS in children and the crucial role of strain typing in epidemiological monitoring. It also illustrates how the remarkable emm-type diversity of S. pyogenes remains a major obstacle to effective vaccine design, despite ongoing efforts with multivalent M-protein-based candidates and alternative strategies targeting conserved antigens. Enhanced global surveillance and inclusive vaccine design are urgently needed to address the full spectrum of circulating GAS strains. Full article

In recent years, the incidence of severe Streptococcus pyogenes (group A Streptococcus, GAS) infections has been increasing worldwide, similar to trends observed prior to the COVID-19 pandemic, alongside a rise in antibiotic resistance. In the present study, we identified the circulating 12 emm types and 8 clusters of 70 GAS isolates among inpatients, investigated their association with antibiotic susceptibility, and compared these findings with earlier research conducted in our country. The predominant emm types and clusters were emm1, emm3, and emm4, and A-C3, E4, and, A-C5, respectively. emm1 was the most common among patients with skin and soft tissue infections or pneumonia, while emm3 was detected in patients with peritonsillar abscesses. All isolates demonstrated susceptibility to penicillin and linezolid, whereas the prevalence of resistance to macrolides, lincosamides, and tetracyclines was found to be 14.3%, 14.3%, and 18.6%, respectively. A notable change in the distribution of emm-types/clusters has been observed, with emm1/A-C3 now identified as the most prevalent, differing from our previous study conducted in the pre-COVID-19 period. Additionally, we noted a decrease in resistance to macrolides attributed to a lower prevalence of emm28 clone. The current research is important for monitoring isolates responsible for severe infections, which is crucial for GAS surveillance. Full article

Background: Eosinophilic esophagitis (EoE) is a chronic, immune-mediated esophageal disorder characterized by Th2-driven inflammation. Clinically, it manifests as esophageal dysfunction, including dysphagia and food impaction, and is frequently associated with atopic comorbidities. Methods: Diagnosis is established via histologic confirmation of ≥15 eosinophils per high-power field (hpf) on esophageal biopsy. Clinical presentation varies, ranging from subtle dysphagia to severe complications necessitating urgent endoscopic intervention. Results: Disease progression is characterized by esophageal remodeling, encompassing fibrosis, angiogenesis, and muscular hypertrophy. Management strategies require individualized, long-term approaches aimed at symptom control and prevention of structural complications. Discussion: Advances in the last decade have refined diagnostic criteria, standardized endoscopic scoring systems, and introduced novel therapeutic agents, including biologics. This review synthesizes current evidence regarding epidemiology, clinical manifestations, diagnostics, and therapeutic strategies. Full article

Streptococcus pyogenes (Group A Streptococcus, GAS) is a major human pathogen capable of causing infections ranging from mild pharyngitis and impetigo to severe invasive diseases such as bacteremia, necrotizing fasciitis, and streptococcal toxic shock syndrome (STSS). Historically, the incidence of GAS infections declined during the early antibiotic era but began rising again from the early 2000s, driven partly by the emergence of hyper-virulent strains such as emm1 and emm12. From 2005 onward, significant increases in GAS infections were reported globally, accompanied by rising antibiotic resistance, particularly to macrolides and tetracyclines. During the COVID-19 pandemic, widespread public health measures led to a sharp decline in GAS infections, including invasive cases, but this trend reversed dramatically in late 2022 and 2023, with surges exceeding pre-pandemic levels, notably in children. Recent data implicate factors such as “immunity debt,” viral co-infections, and the spread of virulent clones like M1UK. Looking forward, continued surveillance of GAS epidemiology, virulence factors, and resistance patterns is critical. Moreover, the emergence of GAS isolates with reduced susceptibility to beta-lactams underscores the need for vigilance despite the absence of fully resistant strains. The development of an effective vaccine remains an urgent priority to reduce GAS disease burden and prevent severe outcomes. Future research should focus on vaccine development, molecular mechanisms of virulence, and strategies to curb antimicrobial resistance. Full article

Streptococcus pyogenes (GAS) is a leading cause of acute otitis media (AOM) and its complications. This study aimed to evaluate the antimicrobial resistance of all isolated bacterial agents recovered from children with AOM and to perform the emm typing of GAS isolates. Antibiotic susceptibility testing was evaluated according to EUCAST criteria. Phenotyping and genotyping were performed for the macrolide-resistant GAS isolates. All GAS isolates were subjected to emm typing. Among the 103 AOM cases considered, we identified GAS isolates (39.4%), Staphylococcus aureus (26.6%), Haemophilus influenzae (13.8%), Streptococcus pneumoniae (11.7%), Moraxella catarrhalis (7.4%), and Serratia marcescens (1.1%). GAS exhibited 32.4% macrolide resistance and 10.8% clindamycin resistance. The M phenotype and mefE gene (18.9%) were the most common, followed by cMLSB (10.8% with ermB), a combination of mefA and ermB (8.1%), and iMLSB (2.7% with ermA). The most prevalent emm types were emm12 (27.0%), emm1 (21.6%), and emm3 (16.2%). The most common GAS emm types identified among AOM patients in this study are found worldwide and are associated with invasive infections in various countries. This may influence the virulence and invasive potential of these strains. Full article

An increase in invasive group A streptococcal (iGAS) infections among children under 15 years of age was reported in several countries between late 2022 and early 2023. This retrospective study aims to describe the epidemiology and clinical features of iGAS infections in children in Cyprus during the same period. Medical records of patients under 16 years old admitted with iGAS infection to the Archbishop Makarios Hospital, the only tertiary paediatric referral centre in Cyprus, between 1 January 2021 and 30 June 2024, were reviewed. Twenty-two cases were identified, of which twenty were classified as confirmed and two as probable. Half of the cases occurred in children aged 0–4 years, and 59% were recorded between December 2022 and April 2023. Scarlet fever was diagnosed in six children, five of whom developed pneumonia and empyema. Streptococcal toxic shock syndrome (STSS) was observed in five patients, resulting in two deaths and one case requiring prolonged extracorporeal membrane oxygenation (ECMO). The overall case fatality rate was 9.1%. Emm 1, belonging to the M1UK clone, was the predominant strain (66.6%). The findings underscore the severity of iGAS infections, particularly in younger children, and highlight the importance of timely diagnosis, appropriate management and continued epidemiological surveillance. Full article

This work presents a comparative design of the sensing elements for the Lunar Dust GRID System (LD GRIDS), a dust analyser conceived to measure charged particles on future lunar missions. LD GRIDS replaces traditional electrodes with continuous conductive grids, i.e., the sensing elements of the instrument, which are able to collect induced charge when charged particles pass through them. The investigation focuses on evaluating the influence of various grid geometrical parameters (size, thickness, and patterns) on the sensor’s performance, either from an electrical or a mechanical perspective. All simulations were carried out using off-the-shelf numerical modelling software, where electrostatic simulation (i.e., induction performance), modal analysis, and quasi-static structural responses under a high acceleration quasi-static load were examined. The results indicate that while grids with round patterns tend to produce a higher induced charge, they also experience higher localised stresses compared to square pattern ones. Moreover, grid size does not significantly affect the instrument sensitivity, whereas increasing the grid thickness significantly reduces peak stresses, with only minor effects on electrostatic performance. Overall, the findings provided valuable insights for optimising the LD GRIDS design, aimed at balancing either electrostatic sensitivity or mechanical resistance, facing the harsh lunar environment. Full article

Electrolytic metallic manganese (EMM) is used as an alloying metal to provide resistance to abrasion and corrosion. Highly pure EMM is obtained through electrorecovery or electrowinning. Efforts are ongoing to improve the efficiency and profitability of this process, as 85 to 90% of manganese is produced by the mining industry. This study applied computer-aided engineering (CAE) to provide information on the behavior of the potential distribution at the electrodes in cells separated by membranes, which allows for the optimization of the EMM production process. The experimental results obtained galvanostatically for EMM allowed for validation of the simulation parameters. It was determined that the cell with 11 compartments is more suitable compared to cells with fewer compartments, since it has lower oxidation-normalized current density and oxidation potential, which affect the distribution of cathodic potential in the process of obtaining EMM. The simulation highlighted a better distribution of the cathodic and anodic potentials due to the increase in the number of electrodes. This saves time and resources in the design of electrochemical cells with a greater number of compartments. Full article

A comprehensive roadmap for advancing Electric Micromobility (EMM) systems addressing the fragmented and scarce information available in the field is defined as a transformative solution for urban transportation, targeting short-distance trips with compact, lightweight vehicles under 350 kg and maximum speeds of 45 km/h, such as bicycles, e-scooters, and skateboards, which offer flexible, eco-friendly alternatives to traditional transportation, easing congestion and promoting sustainable urban mobility ecosystems. This review aims to guide researchers by consolidating key technical insights and offering a foundation for future exploration in this domain. It examines critical components of EMM systems, including electric motors, batteries, power converters, and control strategies. Likewise, a comparative analysis of electric motors, such as PMSM, BLDC, SRM, and IM, highlights their unique advantages for micromobility applications. Battery technologies, including Lithium Iron Phosphate, Nickel Manganese Cobalt, Nickel-Cadmium, Sodium-Sulfur, Lithium-Ion and Sodium-Ion, are evaluated with a focus on energy density, efficiency, and environmental impact. The study delves deeply into power converters, emphasizing their critical role in optimizing energy flow and improving system performance. Furthermore, control techniques like PID, fuzzy logic, sliding mode, and model predictive control (MPC) are analyzed to enhance safety, efficiency, and adaptability in diverse EMM scenarios by using cutting-edge semiconductor devices like Silicon Carbide (SiC) and Gallium Nitride (GaN) in well-known configurations, such as buck, boost, buck–boost, and bidirectional converters to ensure great efficiency, reduce energy losses, and ensure compact and reliable designs. Ultimately, this review not only addresses existing gaps in the literature but also provides a guide for researchers, outlining future research directions to foster innovation and contribute to the development of sustainable, efficient, and environmentally friendly urban transportation systems. Full article