Search Results (2,314)

This research evaluates Battery Energy Storage Systems (BESS) and Compressed Air Vessels (CAV) as complementary solutions for enhancing micro-grid resilience, flexibility, and sustainability. BESS units ranging from 5 to 400 kWh were modeled using a Nonlinear Autoregressive Neural Network with Exogenous Inputs (NARX) neural network, achieving high SOC prediction accuracy with R² > 0.98 and MSE as low as 0.13 kWh². Larger batteries (400–800 kWh) effectively reduced grid purchases and redistributed surplus energy, improving system efficiency. CAVs were tested in pumped-storage mode, achieving 33.9–57.1% efficiency under 0.5–2 bar and high head conditions, offering long-duration, low-degradation storage. Waterhammer-induced CAV storage demonstrated reliable pressure capture when Reynolds number ≤ 75,000 and Volume Fraction Ratio, VFR > 11%, with a prototype reaching 6142 kW and 170 kWh at 50% air volume. CAVs proved modular, scalable, and environmentally robust, suitable for both energy and water management. Hybrid systems combining BESS and CAVs offer strategic advantages in balancing renewable intermittency. Machine learning and hydraulic modeling support intelligent control and adaptive dispatch. Together, these technologies enable future-ready micro-grids aligned with sustainability and grid stability goals. Full article

Background: Efflux-mediated macrolide resistance represents an emerging threat in Streptococcus infections globally. However, molecular epidemiological data from the Gulf region, particularly the United Arab Emirates (UAE), remain limited. This study addresses this knowledge gap by investigating efflux pump resistance mechanisms in clinical Streptococcus isolates. Methods: A cross-sectional study analyzed 100 clinical isolates (99 Streptococcus and 1 Enterococcus) from Thumbay Hospital, Ajman, UAE (October–December 2024). Antimicrobial susceptibility testing for minimum inhibitory concentration (MIC) determination was performed using the DxM 1096 MicroScan WalkAway system (Beckman Coulter Inc., Brea, CA, USA; LabProv4.42). PCR detected mef(A/E), msr(D), and tet(K) resistance genes with sequencing confirmation. Comparative genomic analysis was performed using a total of 30 publicly available Streptococcus genomes: 15 from India and 15 from Saudi Arabia. Statistical analysis employed chi-square tests, Fisher’s exact tests, and multivariate logistic regression with Bonferroni correction (α = 0.05). Results: Among the isolates, erythromycin resistance occurred in 39 isolates (39%, 95% CI: 29.4–49.2%) and clindamycin resistance in 31 isolates (31%, 95% CI: 22.1–40.9%). The mef(A/E) gene was detected in 31 isolates (31%, 95% CI: 22.1–40.9%), and msr(D) in 3 isolates (3%, 95% CI: 0.6–8.5%), with co-occurrence in 3 isolates (3%). No isolates harbored tet(K). Multivariate analysis identified mef(A/E) as the strongest predictor of macrolide resistance (OR = 18.7, 95% CI: 7.9–44.2, p < 0.001). Regional comparison revealed significant differences: mef(A/E) prevalence was 31% (UAE), 87% (India), and 0% (Saudi Arabia) (p < 0.001). Conclusions: This study provides the first molecular characterization of efflux-mediated macrolide resistance in UAE Streptococcus isolates. The predominance of mef(A/E)-mediated resistance with confirmed efflux activity highlights the clinical significance of active surveillance and targeted antimicrobial stewardship in the region. Full article

The recently adopted EU Nature Restoration law emphasises the urgent need to address the ecological impacts of river barriers, which fragment habitats and disrupt natural flows. However, efforts to remove barriers are often constrained by prohibitive costs, regulatory hurdles, and public opposition. In Ireland, barrier removal costs range between EUR 200,000 and EUR 500,000 per structure, representing a substantial financial burden given that more than 73,000 barriers are identified nationwide. Although removal would restore ecological function, it would also eliminate the potential to repurpose these structures for hydropower, thereby reducing opportunities to contribute to the national target of 80% renewable electricity generation by 2030. This study outlines the development of a river barrier modification system to serve the dual purposes of upstream and downstream fish lift over barriers and generation of electricity for local consumption using a fish-friendly pump-as-turbine unit. Under normal flows, the unit generates electricity while during low flows it operates in pumping mode to enable fish passage. A prototype was fabricated and tested at a fish farm using both artificial and live fish. An assessment of the regional potential was also extrapolated from preliminary results suggesting that the BMS offers a cost-effective alternative to full barrier removal, potentially offsetting costs by 50–85% while contributing to both EU restoration targets and national renewable energy goals. Full article

Background/Objectives: Prussian blue (PB) is the agent of choice for internal cesium (Cs) decorporation, yet its performance is critically dependent on gastrointestinal (GI) pH and formulation attributes. Hypochlorhydria, common in patients treated with proton pump inhibitors, may alter the stagewise distribution of Cs binding during GI transit. This study aimed to compare the performance of different PB formulations in sequential in vitro models simulating normogastria and hypochlorhydria: normogastric regimen (NG) and hypochlorhydric regimen (HC). Methods: A static, enzyme-free sequential model was applied using compendial simulated fluids (SGFs pH 1.2 or acetate pH 4.0, SIF pH 6.8, and phosphate buffer pH 7.2). The formulations tested included PB active pharmaceutical ingredient (API) (bulk), compression blend, PB tablets 500 mg (PB tablets), and Radiogardase^®. For each stage, cesium bound (qs, mg/g PB), fractional contributions (fs), and total capture (qtotal) were quantified. Additional analyses included sensitivity to initial Cs concentration (C₀) and desorption in mineralized water. Results: Overall performance was primarily determined by formulation (p < 0.0001), with a significant formulation × regimen interaction. The compression blend and PB tablets exhibited the highest decorporation capacity, PB-API showed intermediate performance, and Radiogardase^® was clearly lower. Under HC, capture was concentrated in the gastric stage (44–47%), whereas in NG, it shifted toward intestinal stages. Desorption in the mineralized water was statistically significant but negligible compared with total capture, supporting the stability of cesium sequestration. Conclusions: Formulation and gastric acidity regimens not only determine the total cesium capture but also redistribute it across the GI tract. PB tablets represent an effective and accessible alternative to Radiogardase^®, maintaining robust decorporation capacity under clinically relevant pH conditions. Full article

Although aging is an irreversible process, the rate of aging can be delayed by a reasonable diet. As a nutrient-dense natural product, royal jelly (RJ) has an enormous potential for applications in medicine and health promotion. However, the exact physiological activity of RJ with varying freshness and concentration has not been fully clarified, and more investigation is needed to determine their precise contributions. Here, fresh RJ (just produced recently) and RJ stored for 2 weeks at −20 °C, 4 °C or 25 °C were tested at concentrations of 100, 50, 25 and 12.5 μg/mL on Caenorhabditis elegans. Fresh RJ, with concentrations of 100 μg/mL, 50 μg/mL and 25 μg/mL, could extend the lifespan of C. elegans by 16.37%, 9.53% and 4.32%, while RJs stored at 4 °C and 25 °C were ineffective. In terms of body length, treatment with fresh RJ significantly enlarged the body size by around 48%. Although RJ stored at 4 °C and 25 °C could also promote nematode growth, its activity diminishes as storage temperature increases. RJs stored at −20 °C and 4 °C with concentrations of 100 μg/mL significantly increased the pumping rate of nematodes by 58% and 50%. But non-fresh RJ or low-concentration RJ (≤25 μg/mL) had no effects on the motility of C. elegans. In addition, fresh RJ could improve the reproductive capacity of C. elegans, with the highest increase reaching approximately 25%. Even when stored at 25 °C, RJ also significantly enhanced the reproductive capacity of C. elegans, increasing it by approximately 14.8%. Moreover, qPCR showed that RJ could significantly affect the expression of multiple genes associated with aging and vitality. Fresh RJ significantly up-regulated bec1 and hsp16.2 3.19- and 2.80-fold, while RJ stored at 25 °C significantly up-regulated sod3 and gpd1 3.80- and 3.40-fold. Our results suggested that the activity of RJ on C. elegans is related to its freshness and concentration, while RJ also contains active components that are independent of freshness. Therefore, it is necessary to explore effective methods for accurately assessing the freshness of RJ. Full article

Given the growing demand for sustainable energy solutions, this study addresses the challenge of improving the efficiency and environmental performance of residential water heating systems. This work presents the design and implementation of a controller aimed at regulating the outlet water temperature of a direct-expansion solar-assisted heat pump operating with propane. A dynamic model was experimentally identified using the AutoRegressive with eXogenous input methodology and used to design a Proportional–Integral–Derivative controller via the direct synthesis method. To regulate the outlet water temperature, the controller acts on the water flow rate. The effectiveness of the controller was evaluated through computer simulations and experimental tests. Its robustness was assessed by considering parametric variations of ±15%, during which the system maintained stability and performance. The controller demonstrated good accuracy and performance, keeping the desired temperature stable even in the presence of disturbances, both in simulations and experimental evaluations. Full article

With more hybrid heating systems available, there is a need to optimize energy use intelligently from the end-consumer perspective. This paper focuses on a multi-criteria heating system optimization to optimize cost, carbon emission, and comfort level of building occupants. A discrete Multi-Objective Model Predictive Controller (MO-MPC) algorithm is proposed to optimally utilize two heating sources connected to a building, namely district heating (DH) and a building-integrated electrical heat pump (HP). The model is tested on a real-world building case simulated with a gray box building model. The results are compared to a conventional PID controller as well as the MPC scheme, each with a single heating input, and eight different cases are constructed to make this comparison more visible. The results indicate that, using MO-MPC, a cost saving of up to 10% and emission saving of up to 13% can be reached without additional thermal discomfort, while the potential savings on cost and emission with the hybrid system can be up to 25% and 77%, respectively. Further, a sensitivity analysis on price and emission parameters is conducted to investigate the changes in the provided solution. Full article

Shaft misalignment is among the most common faults in rotating machinery, and although many diagnostic methods have been proposed, reliably detecting it under varying load conditions remains a major challenge for vibration-based techniques. To address this issue, this study proposes a new vibration-based misalignment detection framework that leverages cointegration analysis. The approach examines both the stationarity of vibration signals and the residuals derived from the cointegration process. Specifically, it combines the Augmented Dickey–Fuller (ADF) test with cointegration analysis in three stages: (1) applying the ADF test to raw vibration data before cointegration, (2) performing cointegration on the vibration time series, and (3) reapplying the ADF test to the post-cointegrated data. The method was validated using experimental measurements collected from a laboratory-scale test rig comprising a motor, gearbox, and hydraulic gear pump, tested under both healthy and misaligned states with varying degrees of severity. Vibration signals were recorded across multiple load conditions. The results demonstrate that the proposed method can successfully detect misalignment despite load variations, while also providing insights into fault severity. In addition, the residuals from the cointegration process proved to be highly sensitive to damage, highlighting their value as features for vibration-based condition monitoring. Full article

Background/Objectives: Hospital wastewater is a complex effluent containing a wide range of biological and chemical contaminants, including pharmaceuticals, pathogens, and antimicrobial resistance determinants. These discharges pose a growing threat to aquatic ecosystems and public health, particularly in regions where wastewater treatment is insufficient. This study aimed to characterize the chemical and microbiological composition of untreated effluent from a tertiary care hospital in southern Chile, focusing on contaminants of emerging concern. Methods: Wastewater samples were collected at the hospital outlet before any treatment. The presence of two commonly used pharmaceutical compounds, paracetamol and amoxicillin, was quantified using high-performance liquid chromatography (HPLC). Bacterial isolation was performed using selective media, and antibiotic susceptibility testing was conducted via the disk diffusion method following CLSI guidelines. In addition, metagenomic DNA was extracted and sequenced to assess microbial community composition and functional gene content, focusing on the identification of resistance genes and potential pathogens. Results: A total of 42 bacterial isolates were recovered, including genera with known pathogenic potential such as Aeromonas, Klebsiella, and Enterococcus. Antibiotic susceptibility tests revealed a high prevalence of multidrug-resistant strains. Metagenomic analysis identified the dominance of Bacillota and Bacteroidota, together with 56 antimicrobial-resistance gene (ARG) families and 38 virulence-factor families. Functional gene analysis indicated the presence of efflux-pump systems, β-lactamases, and mobile genetic elements, suggesting that untreated hospital effluents serve as potential sources of resistance and virulence determinants entering the environment. Paracetamol was detected in all samples, with an average concentration of 277.4 ± 10.7 µg/L; amoxicillin was not detected, likely due to its instability and rapid degradation in the wastewater matrix. Conclusions: These findings highlight the complex microbiological and chemical burden of untreated hospital wastewater and reinforce the need for continuous monitoring and improved treatment strategies to mitigate environmental dissemination of antibiotic resistance. Full article

The article is devoted to the synthesis, implementation, simulation and experimental study of a real-time Lyapunov-based two-degree-of-freedom model reference adaptive controller (MRAC) for an axial-piston pump. The controller of the developed real-time system determinates control signal values applied to the electro-hydraulic proportional valve. The proportional valve is an actuator for driving the swash plate swivel angle of the pump. The swash plate swivel angle determines the displacement volume of the flow rate of the pump. The MRAC is synthesized based on the experimentally identified mathematical model. To conduct the identification and experimental investigation of the controller, the authors have used an existing laboratory test setup. The comparison of the designed MRAC with conventional PI controller is performed. The control performance analysis is based on integral square error (ISE) in transient responses of the pump flow rate at different flow rate references and loads. Full article

The heart is the body’s core pump. Heart failure impairs the heart’s ability to pump blood, leading to circulatory disorders. The artificial heart (blood pump) is an important mechanical circulatory support device that can partially or completely substitute cardiac pumping function, potentially improving hemodynamic performance and alleviating symptoms of heart failure. A combination of computational fluid dynamics simulation and hydraulic performance testing was used to study key parameters of the impeller, including blade count, blade wrap angle, impeller flow path, and diversion cone height. The goal was to reduce hemolysis risk and enhance pumping efficiency. Increasing the blade count raised the head, with optimal efficiency achieved at seven blades. A larger blade wrap angle decreased the head but improved efficiency. Synchronizing the flow path and diversion cone height at 4.1 mm maximized the head. Under various rotational speeds, the studied hemolysis index remained well below 0.1 g/100 L. Both experimental and simulation data were validated against each other, meeting the required error tolerances. The studied blood pump meets the design specifications. At an operating condition of 5 L/min flow rate and 2800 rpm, the pump achieves the required head and hemolysis criteria with a margin of safety. Full article

To improve shutdown safety for agricultural irrigation pumping stations, this study investigates the synchronous and asynchronous shutdown processes of a pump device using numerical simulations validated by model tests. The results show that during the synchronous shutdown process, vortices appear on the inside of gate as its opening decreases, and their ranges expand accordingly. When the gate is 90% closed, negative pressure zones emerge in the outlet passage. As the gate continues to close, the strength and range of negative pressure zones keep expanding, and air is drawn into the outlet passage. After the gate is fully closed, the water flow starts reciprocating motion with strength attenuation due to inertia and water pressure. Compared with the synchronous shutdown method, the asynchronous shutdown-F1 to F4 achieved significant reductions results: the maximum reverse rotation rate decreased by 17.74%, 39.59%, 59.18%, and 83.35%, respectively, while the maximum reverse volumetric flow rate decreased by 17.32%, 38.45%, 59.20%, and 79.19%, respectively. Furthermore, in asynchronous shutdown-F4, no negative pressure occurs in the outlet passage, even if the gate closes suddenly. Therefore, the asynchronous shutdown method is a safer alternative for irrigation pumping stations. This study proposes more appropriate shutdown methods for pumping stations, which has significant practical value. Full article

This present investigative work proceeds with the statistical study of the heat transfer coefficient (CTC) in the different flow transitions that are formed in a horizontal pipe with variation in the angles of inclination in a collector/evaporator component of a heat pump of solar assisted direct expansion (DX-SAHP) by using R600a refrigerant as working fluid in Quito - Ecuador. The dimensions of the collector/evaporator are 3.8 and 1000 mm inside diameter and length, respectively. To determine the results obtained, five practical tests are carried out with inclination angles of 10, 20, 30, 40 and 45°, with speeds or mass flows that vary between 203.24 and 222.28 kg·m⁻²·s⁻¹, the heat fluxes reached values between 200.58 and 507.23 W·m⁻². The correlations proposed by Kattan, Kundu, and Mohseni, and the experimental data were considered for the analysis of the effects of heat transfer on flow patterns. The results obtained from the investigation show that the maximum CTC is 6163.83 W·m⁻²·K⁻¹ with an inclination angle of 45°. Statistical analysis was performed considering the direction of Pearson presented results that for the angle of inclination of 10° a greater inverse direction of −0.316 is obtained. Full article

High-renewables grids are planned in min but judged in milliseconds; credible studies must therefore resolve both horizons within a single model. Current adequacy tools bypass fast frequency dynamics, while detailed simulators lack multi-hour optimization, leaving investors without a unified basis for sizing storage, shifting demand, or upgrading transfers. We present a two-layer Hierarchical Model Predictive Control framework that links 15-min scheduling with 1-s corrective action and apply it to Germany’s four TSO zones under a stringent zero-exchange stress test derived from the NEP 2045 baseline. Batteries, vehicle-to-grid, pumped hydro and power-to-gas technologies are captured through aggregators; a decentralized optimizer pre-positions them, while a fast layer refines setpoints as forecasts drift; all are subject to inter-zonal transfer limits. Year-long simulations hold frequency within ±2 mHz for 99.9% of hours and below ±10 mHz during the worst multi-day renewable lull. Batteries absorb sub-second transients, electrolyzers smooth surpluses, and hydrogen turbines bridge week-long deficits—none of which violate transfer constraints. Because the algebraic core is modular, analysts can insert new asset classes or policy rules with minimal code change, enabling policy-relevant scenario studies from storage mandates to capacity-upgrade plans. The work elevates predictive control from plant-scale demonstrations to system-level planning practice. It unifies adequacy sizing and dynamic-performance evaluation in a single optimization loop, delivering an open, scalable blueprint for high-renewables assessments. The framework is readily portable to other interconnected grids, supporting analyses of storage obligations, hydrogen roll-outs and islanding strategies. Full article

This study focuses on the pin shaft failure accidents occurring during the construction of concrete pump trucks and hypothesizes that the accidents are caused by improper installation of the pin shaft mounting angle (defined as the angle between the oil passage axis and the horizontal plane). First, the actual operating conditions were simplified to design an equivalent test, through which the stress distribution of the pin shaft under the 360° rotation condition was measured and understood. Then, simulation analysis was conducted to verify the stress concentration phenomenon under different pin shaft mounting angles. The results show that the pin shaft mounting angle at the accident site falls within the high-stress zone centered on the oil cylinder axis, verifying the hypothesis. In addition, the high-stress zone of the pin shaft does not change with the rotation angle of the pin shaft; it is only related to the position of the oil cylinder axis and distributed symmetrically around the oil cylinder axis. Therefore, to prevent the pin shaft failure accidents, the mounting angle of the pin shaft can be adjusted to keep it away from the high-stress zone near the oil cylinder axis. Full article