Search Results (235)

As the global energy sector and maritime industry transition toward carbon neutrality, Carnot batteries have emerged as a critical technology for flexible, long-duration energy management. Carnot batteries, which operate on a Power-to-Heat-to-Power principle, present a highly promising alternative to conventional electrochemical batteries. The present study provides a review of Carnot battery architectures, systematically evaluating their thermodynamic cycles, working fluids, Thermal Energy Storage media and key turbomachinery components. A comparative assessment of the current literature illustrates that system selection requires balancing round-trip efficiency, Energy Storage Density and Technology Readiness Level. According to the findings of the present study, high-temperature Brayton cycles offer robust baseline efficiencies of 60–80% whereas subcritical Rankine cycles benefit from commercial maturity and can achieve efficiencies exceeding 200% when integrated with cryogenic heat sinks like LNG. It should be clarified that efficiency values exceeding 100% represent “Apparent Round-Trip-Efficiencies (RTE)” resulting from the thermodynamic contribution of external exergy streams, such as LNG cryogenic cold, rather than standalone cycle efficiencies, which are strictly below 100%. In addition, volumetric energy density varies drastically based on the physical phase of the storage medium, scaling from under 1 kWh/m³ for unpressurized water to over 385 kWh/m³ for advanced thermochemical systems. Although most configurations currently remain in the prototyping phase, the technology holds transformative potential for the maritime sector. Carnot batteries can deliver a self-contained, zero-emission electrical power supply to cover the vessel’s electrical load requirements during harbor stays and transit within Emission Control Areas (ECAs) by dynamically capturing and storing shipboard waste heat during open sea transit. Full article

Staphylococcus aureus is a major food safety concern because of its ability to produce heat-stable enterotoxins, develop antimicrobial resistance, and express virulence factors associated with persistence and pathogenicity. The present study characterised S. aureus isolates recovered from ready-to-eat (RTE) foods and food handlers’ hands in university food service establishment in northern Portugal, focusing on virulence-associated genes, antimicrobial resistance profiles, and biofilm production. A total of 261 samples were analysed, including 156 RTE food samples and 105 hand swabs. Twenty-nine coagulase-positive staphylococci isolates were recovered and confirmed as S. aureus by detection of the nuc gene, corresponding to an overall prevalence of 11.11% (29/261). Of these, 20 isolates were obtained from food handlers’ hands and 9 from RTE foods. The hla and sei genes were detected in all isolates, while seg and tst were detected in 93.10%; sed was not detected. Biofilm-forming capacity was identified in 44.83% of isolates, with most strains exhibiting weak to moderate biofilm production. Resistance to at least one antimicrobial agent was observed in 31.0% of isolates, and presumptive methicillin-resistant Staphylococcus aureus represented 13.79%, all classified as multidrug-resistant. These findings support the occurrence of handling-related contamination and reinforce the need for strict hygiene practices, temperature control, and continuous monitoring in institutional food service environments. Full article

For image reconstruction in diffuse optical tomography (DOT), both accurate mathematical modeling of light propagation in biological tissue and robust inverse modeling are essential. This study evaluates the validity of the radiative transfer equation (RTE) as a forward model for DOT of the thyroid gland, which surrounds the air-filled trachea anteriorly, by comparing it with the photon diffusion equation (PDE). Distributions of photon time-of-flight (DTOFs) were obtained from numerical solutions of the RTE and the PDE in a homogeneous phantom and in a phantom containing four cylindrical holes. The refractive-index mismatch at the cylindrical hole walls (refractive index 1.511) was explicitly modeled by incorporating boundary conditions into the RTE solver, where refraction angles were determined using Snell’s law and the reflection coefficient was calculated based on Fresnel’s law. These simulated DTOFs were compared with experimental measurements acquired using a time-domain near-infrared spectroscopy (TD-NIRS) system. The results demonstrate that the RTE describes light propagation in media containing hollow regions more accurately than the PDE. Future work will apply this RTE framework to model light propagation in the human thyroid gland and improve the diagnostic accuracy of thyroid nodules. Full article

Shelf-life prediction is crucial for the industrial development and quality preservation of ready-to-eat (RTE) Tremella fuciformis cold dishes. In this study, we investigated the quality deterioration kinetics of T. fuciformis RTE dishes during storage at 5 °C, 15 °C, and 25 °C to establish an Arrhenius-based shelf-life prediction model. Throughout the storage period, the total bacterial count (TBC), viscosity, b* value, and malondialdehyde (MDA) content continuously increased, whereas firmness and sensory scores exhibited a negative correlation with storage time. The interpolated microbiological shelf-life endpoints, determined as the time required for TBC to reach 5.0 log CFU/g, were 19.01, 5.53, and 1.58 days at 5 °C, 15 °C, and 25 °C, respectively. Pearson correlation analysis identified TBC and MDA as the primary predictive indicators, with both parameters strictly conforming to zero-order reaction kinetics. Validation of the Arrhenius-based models revealed that the TBC-based model showed lower internal prediction error within the tested temperature range (average relative error of 8.92%), significantly outperforming the MDA model, which exhibited poor reliability (30.41% average relative error). These findings provide a practical reference for cold-chain management and shelf-life estimation of RTE T. fuciformis products for optimizing cold-chain management and ensuring the microbiological safety of RTE T. fuciformis products. Full article

Buffalo meat is widely consumed in Egypt; however, it may pose serious food safety risks due to microbial contamination during handling, preparation, and processing. This study investigated the prevalence and characterization of multidrug-resistant (MDR) enterotoxigenic Staphylococcus aureus in raw ground buffalo meat and ready-to-eat (RTE) kofta and liver sandwiches marketed in Mansoura, Egypt. S. aureus was detected in 62% (62/100) of raw buffalo ground meat, 41% (41/100) of RTE kofta, and 60% (60/100) of RTE liver samples, with an overall prevalence of 54.3% (163/300). All 660 isolates were confirmed as S. aureus via nuc gene detection, among which 46.8% (309/660) were mecA-positive and verified as methicillin-resistant (MRSA), and 21.8% (144/660) were vanA-positive and verified as vancomycin-resistant (VRSA). Enterotoxigenic strains were identified in 42.7% (282/660) of isolates, with the sea gene being most prevalent (67.7%; 191/282), followed by seb (58.2%; 164/282) and sec (39.7%; 112/282). The highest frequency of enterotoxigenic strains occurred in raw ground meat (47.2%), followed by kofta (45.1%) and liver (36%). Antimicrobial susceptibility testing against 15 antibiotics revealed that 7.6% (50/660) of isolates were extensively drug-resistant (XDR) with a MAR index of 0.9, while 82.9% (547/660) were MDR with MAR values between 0.3 and 0.7, indicating exposure to environments of intensive antibiotic use. The present findings highlight a high contamination level of buffalo meat products with MDR enterotoxigenic MRSA and VRSA, representing a significant public health hazard. Implementation of strict hygiene measures, wise antibiotic usage, and continuous surveillance is essential to control their dissemination through the food chain. Full article

Obesity has emerged as a significant global public health challenge, yet the clinical utility of existing anti-obesity drugs is often constrained by limited efficacy and adverse safety profiles. Rheum tanguticum Maxim. ex Balf., a traditional medicinal plant, has shown potential in modulating glucose and lipid metabolism; however, its specific anti-obesity mechanisms remain poorly characterized. In this study, the chemical profile of the 60% ethanol-eluted fraction of R. tanguticum (RTE) was characterized via UPLC-QTOF/MS, followed by network pharmacology analysis to predict regulatory targets and enriched pathways. Subsequently, a high-fat diet (HFD)-induced obese mouse model was established to evaluate the anti-obesity effects of RTE by monitoring body weight, Lee’s index, fat-to-body weight ratio, serum lipid profiles, and liver histopathological changes. A total of 14 major compounds, primarily anthraquinone glycosides, were identified. Integrated network analysis identified 10 hub targets, including TNF, EGFR, and TP53. In vivo experiments demonstrated that RTE significantly attenuated body weight gain and reduced Lee’s index, fat-to-body ratios, and serum levels of TC, TG, and LDL-C. Furthermore, RTE treatment markedly alleviated hepatic steatosis and inflammatory infiltration in obese mice. These findings suggest that RTE exerts potent anti-obesity effects through a multi-target and multi-pathway mechanism that regulates lipid metabolism and suppresses inflammation. This study improves our understanding of the pharmacological value of R. tanguticum and provides a scientific basis for its development as a functional food ingredient or therapeutic agent against obesity. Full article

Although long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs) are typically passed down to descendants as part of the genome, the Bov-B LINE was likely horizontally transferred from a snake to the ancestor of ruminants. Plant RTE-clade LINEs and their associated SINEs possess a genomic insertion signature different from that of mammalian L1 LINEs. However, the reason for the increased frequency of horizontal transfer in RTE-clade LINEs such as Bov-B relative to that in L1-clade LINEs has not yet been clarified. In this study, we identified family members of the reptilian Bov-B LINE and associated Sauria SINE across various squamate species to determine the amplification timing of the LINE. The findings revealed that the LINE may be over 180 million years old. Moreover, profiling of target site duplications showed that a characteristic genomic insertion signature of the LINE and SINE closely resembled the signature of the plant RTE-clade LINEs. We conducted phylogenetic analyses of RTE-clade LINEs with characteristic genomic insertion signatures and estimated their divergence times. The findings suggest an ancient origin (over 411 MYA) of the retrotranspositional mechanism underlying this signature; however, a complex evolutionary trajectory of LINEs across species warrants further investigation. Full article

The growing penetration of variable renewable energy sources transforms power grid dispatch into a high-dimensional, stochastic, and multi-agent decision-making problem that challenges both classical optimization and standard Reinforcement Learning (RL) methods. Traditional RL policies, typically parameterized as unimodal Gaussians, lack the expressiveness to capture the multimodal action distributions that arise when multiple feasible dispatch strategies coexist, while diffusion-based generative policies achieve expressiveness at the cost of prohibitively many iterative denoising steps during inference. We propose Multi-Agent Flow-based Q-Learning (MAFQL), a framework that addresses this expressiveness–efficiency tradeoff by integrating conditional flow matching with conservative Q-learning under a Centralized Training with Decentralized Execution (CTDE) architecture. The framework consists of a unified training pipeline that combines four learning objectives: behavior cloning, flow matching, conservative Q-learning, and distillation. This allows for expressive policy generation through only 1–5 ODE integration steps. Measured per-agent inference latencies below $8\mathrm{ms}$ (P99) are achieved on both GPU and CPU hardware, which is compatible with the response requirements of automatic generation control. We formulate the dispatch task as a Dec-POMDP over three physically grounded control zones derived from the RTE network topology and evaluate MAFQL on the IEEE 118-bus and 14-bus systems in the Grid2Op simulator. Empirical results show that MAFQL CTDE substantially outperforms all tested baseline methods on the 118-bus system under a composite multi-objective reward function and that it demonstrates initial cross-scale generalizability on the 14-bus system. The decentralized execution variant consistently outperforms centralized execution, consistent with the hypothesis that distillation facilitates effective knowledge transfer. At the end of the paper we discuss current limitations such as the absence of ablation studies, end-to-end latency measurements, and formal safety guarantees, then outline directions for addressing them. Full article

This study presents a comprehensive exergy-based thermodynamic analysis of a standalone liquid air energy storage (LAES) system integrated with internal thermal storage and an Organic Rankine Cycle (ORC) for sustainable large-scale energy storage applications. Unlike conventional studies, this work focuses on providing a scalable design framework by quantifying storage fluid requirements on a per-unit-mass-flow and per-MWh-capacity basis, enabling the results to be generalized for various power outputs and storage capacities. The proposed system configurations with two- and three-stage compression were compared in terms of liquid yield, round-trip efficiency (RTE), exergy efficiency, and storage fluid requirements. Results indicate that the optimal operating pressures are 190 bar for charging and 130 bar for discharging. At 200 bar charging pressure, the liquid yield increases from 0.51 (at 60 bar) to 0.86, while the maximum RTE reaches 62% in the base case and 68% with ORC integration. Incorporating ORC enhances the RTE by approximately 6–7% compared with conventional configurations through improved low-grade waste heat recovery and energy utilization. The two-stage compression configuration with ORC demonstrates the best thermodynamic performance, providing higher exergy efficiency, greater net power output, and lower thermal storage requirements. Furthermore, the reduction in thermal storage fluid demand contributes to improved resource utilization and lower infrastructure requirements for large-scale deployment. Additional sensitivity analyses indicate that thermal losses significantly reduce system performance, whereas ambient temperature fluctuations within ±15 K have only a minor influence on round-trip efficiency and liquid yield due to compensating effects between charging and discharging processes. The findings of this study provide scalable design insights for LAES systems and demonstrate the potential of ORC-assisted LAES technology to support renewable energy integration, sustainable grid flexibility, and low-carbon energy infrastructure development. Full article

Over the last two decades, the automotive industry has spearheaded a shift toward data-centric manufacturing, where Real-Time Ethernet (RTE) networks defined in IEC61784-2 serve as critical components for ensuring deterministic communication at the Operation Technology level. Although AI-based systems offer significant potential for predictive maintenance and cybersecurity, their effectiveness is currently limited by a lack of structured datasets from real-world industrial environments. Most existing research relies on small-scale simulations or laboratory setups that fail to capture the scale and complexity of actual production. To address this gap, this paper introduces a novel methodology for repurposing network data collected throughout a plant’s lifecycle, specifically during the commissioning and validation phases of RTE networks according to IEC61918. An additional important contribution is the creation of the first multi-plant dataset for real RTE (PROFINET) traffic in the automotive sector, aggregating 300 GB of data from 54,000+ devices across nearly 700 production lines in 17 industrial sites. The work defines standardized methodologies and replicable processes for systematic data acquisition, validation, and labeling to ensure long-term usability for training AI models. Finally, four case studies (focused on performance, maintenance, security, and machine learning) show how this dataset can be used to enhance the reliability of modern smart manufacturing. Full article

Background: Spasticity is a common and disabling symptom of multiple sclerosis (MS), yet its assessment remains challenging. Clinical scales such as the Ashworth Scale (AS) evaluate resistance to passive movement, whereas neurophysiological measures (e.g., H-reflex, F-wave) provide objective indices of α-motoneuron excitability but correlate inconsistently with clinical severity. Real-time ultrasound elastography (RTE) enables semi-quantitative, in vivo assessment of muscle stiffness, while the recently introduced Muscle Elastography Multiple Sclerosis Score (MEMSs) aims to classify muscle spasticity in MS. Objective: To evaluate the utility of RTE using MEMSs for the objective assessment of muscle status in MS patients with spasticity, and to compare elastographic findings with clinical and neurophysiological measures. Methods: In this single-center study, 26 MS patients (diagnosed according to the 2017 McDonald criteria) and age- and sex-matched healthy controls (n = 27) were enrolled. Spasticity was graded using the AS. All participants underwent bilateral RTE of the gastrocnemius muscle, with images independently scored by two blinded neurologists using the 5-point MEMSs scale. Neurophysiological assessment included the soleus H-reflex, with calculation of H/M ratios. Correlations were analyzed using Pearson’s coefficient, and inter-observer reliability was assessed. Results: No consistent or statistically robust associations were found between clinical spasticity severity (AS scores) and either neurophysiological or elastographic parameters. Several MEMSs did not correlate reliably with AS grades, and neurophysiological measures showed limited discriminatory ability between MS patients and healthy controls. Correlations between neurophysiological and elastography parameters were weak to moderate (ρ ranging from −0.49 to 0.45). Inter-observer reliability of MEMSs scoring ranged from poor to moderate across the examined muscle groups, with Cohen’s κ values ranging from −0.02 to 0.54. Conclusions: RTE using MEMSs did not demonstrate sufficient validity or reproducibility for assessing muscle spasticity in MS, showing poor agreement with both clinical and neurophysiological measures. Full article

Listeria monocytogenes remains a major foodborne pathogen associated with ready-to-eat (RTE) products, including smoked fish. This study investigated the occurrence, molecular characteristics, virulence gene profiles, and antimicrobial susceptibility of L. monocytogenes isolated from retail smoked fish in Poland. A total of 46 samples (cold- and hot-smoked products) collected from 15 producers and five retail chains were analyzed using ISO 11290-1:2017 for qualitative detection and ISO 11290-2:2017 for enumeration. Listeria spp. were detected in 5/46 samples (10.9%), including 4 isolates confirmed as L. monocytogenes (8.7%). All positive samples originated from cold-smoked salmon, with a prevalence of 4/13 (30.8%) in this product category. The quantitative analysis indicated that contamination levels in all positive samples were below 100 CFU/g. Molecular serogrouping and multiplex PCR demonstrated the presence of key virulence-associated genes, including hlyA, prfA, plcB, and actA, consistent with potentially pathogenic profiles. Pulsed-field gel electrophoresis (PFGE) revealed clustering of isolates, indicating genetic relatedness among strains obtained from different retail sources. Antimicrobial susceptibility testing using the MICRONAUT system showed that all L. monocytogenes isolates were susceptible to first-line therapeutic agents, including ampicillin and penicillin, according to EUCAST/CLSI criteria. Although contamination levels were low and isolates remained susceptible to clinically relevant antimicrobials, the detection of virulence-associated strains in RTE smoked fish highlights the need for continuous monitoring and strict hygienic control in the production and retail chain. These findings contribute to regional surveillance data on L. monocytogenes in smoked fish products in Poland. Full article

With rising incidence in recent years, Listeriosis, a severe foodborne disease in humans primarily transmitted through ready-to-eat (RTE) foods contaminated with Listeria monocytogenes, became the most severe zoonotic disease in the European Union (EU) in 2024 with the highest hospitalization and mortality rates, prompting stricter regulatory requirements under Regulation (EC) No 2073/2005 and its recent amendments. This systematic literature review aimed to evaluate the availability, validity and quality of published challenge test data on the growth potential and maximum growth rate of Listeria monocytogenes in RTE foods to identify data gaps and, if possible, to support the derivation of a classification of RTE foods into the two existing regulatory categories, a and b (not able and able to support the growth of Listeria monocytogenes). Conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the Cochrane Handbook, a comprehensive database search was done to identify eligible challenge test studies on Listeria monocytogenes growth in RTE foods, followed by structured screening and quality assessment based on the EURL Lm Technical Guidance Documents. A limited and heterogeneous body of published challenge test data on the growth potential and maximum growth rate of Listeria monocytogenes in RTE foods was identified, with substantial data gaps across multiple food groups, precluding meta-analysis and limiting regulatory applicability under the current regulations. Overall, the available literature is insufficient to reliably support regulatory classification or to enable direct extrapolation by food business operators (FBO), underscoring the need for product-specific investigations and food group-specific guidance for food safety. Full article

Listeria monocytogenes is considered a highly persistent risk for public health in food production facilities. Food business operators manufacturing ready-to-eat foods (RTE) are required to sample processing areas for L. monocytogenes as part of their environmental monitoring plans. The aim of the study was to identify suitable sampling devices, demonstrating the crucial role of the sampling technique in the method performance for L. monocytogenes monitoring. Detection of Listeria spp. and L. monocytogenes from surfaces in an RTE food production facility was evaluated by using two different sampling methods (swabs and sponges). When using swabs, 46 sampling points were negative for both targets. However, when sampling same points with sponges, 30% samples (14 out of 46) were positive for Listeria spp. with 8 samples (17%) positive for L. monocytogenes. During subsequent in vitro experiments, L. monocytogenes strains spiked onto three different surfaces (stainless steel, Teflon and epoxy) showed recoveries of between 76% and 93% when using sponges, while in swabs, recoveries where always below 50%. All L. monocytogenes strains isolated belonged to the major clonal complexes (CC) circulating in Europe in food industry (e.g., CC121 and CC9) and none of them are considered among the hypervirulent strains. Genomic analysis, including new tools for source tracking (Gene Up Typer, bioMérieux) showed differences between strains isolated from different risk hygienic zones. Full article

Ready-to-eat (RTE) fresh salads are widely consumed for their convenience and nutritional value, but they could represent a relevant food safety concern, as they do not undergo a lethal heat treatment before consumption, and furthermore, they may support the growth of Listeria monocytogenes during refrigerated storage. In this study, the growth potential of L. monocytogenes was evaluated by standardised challenge tests in five commercially available RTE salads: crispy lettuce, baby lettuce, a baby lettuce–spicy mustard mix, and two mâche products from different producers. Three different batches for each product were inoculated with a three-strain cocktail of L. monocytogenes at a target level of approximately 2–3 log CFU/g and stored under conditions simulating reasonably foreseeable refrigerated storage (7 °C for approximately two-thirds of their shelf life, followed by 10 °C for the remaining one-third), in accordance with ISO 20976-1 and EURL L. monocytogenes guidelines. The growth potential (Δ) was calculated as the difference between the highest mean L. monocytogenes concentration observed during storage and the mean of the initial concentration at time zero, both in three replicate samples; Δmax was defined as the highest Δ value among the tested batches. Crispy lettuce, baby lettuce, and the mixed salad supported the growth of L. monocytogenes, with Δmax values of 2.33, 2.60, and 3.65 log CFU/g, respectively. In contrast, both mâche products showed Δmax values ≤ 0.5 log CFU/g, indicating an inability to support pathogen growth under the tested conditions. These results demonstrate that the growth potential of L. monocytogenes in RTE salads is strongly product-specific and likely influenced by intrinsic characteristics and background microbiota, as well as by storage temperature. The findings underline the importance of strict temperature control and product-specific risk assessment to ensure compliance with microbiological criteria throughout shelf life and to mitigate the risk of listeriosis associated with RTE salads. Full article