Search Results (5,958)

This study presents the first investigation into the application of ultrasonic vibration-assisted electrical discharge machining (UV-EDM) using graphite electrodes for external cylindrical surface machining—an essential surface in the production of tablet punches and sheet metal-forming dies. A custom ultrasonic horn was designed and fabricated using 90CrSi material to operate effectively at a resonant frequency of 20 kHz, ensuring stable vibration transmission throughout the machining process. A Box–Behnken experimental design was employed to explore the effects of five process parameters—vibration amplitude (A), pulse-on time (Ton), pulse-off time (Toff), discharge current (Ip), and servo voltage (SV)—on two key performance indicators: material removal rate (MRR) and surface roughness (Ra). The optimization process was conducted in two stages: single-objective analysis to maximize MRR while ensuring Ra < 4 µm, followed by a hybrid multi-objective approach combining NSGA-II and the Analytic Hierarchy Process (AHP). The optimal solution achieved a high MRR of 9.28 g/h while maintaining Ra below the critical surface finish threshold, thus meeting the practical requirements for punch surface quality. The findings confirm the effectiveness of the proposed horn design and hybrid optimization strategy, offering a new direction for enhancing productivity and surface integrity in cylindrical EDM applications using graphite electrodes. Full article

Background: Preterm infants and their families face a challenging experience during their stay in the neonatal intensive care unit (NICU). Family-centered care emphasizes the importance of welcoming parents, involving them in their baby’s daily care, and supporting the development of parenting skills. NICU staff should support parents in understanding their baby’s needs and in strengthening the parent–infant bond. Although many tools outline what parents should learn, there is a limited structured framework to monitor their involvement in the infant’s care. Tracking parental participation in daily caregiving activities could support professionals in effectively guiding families, ensuring a smoother transition to discharge. Aims: The aim of this study was to evaluate the adherence to and effectiveness of a structured tool for parental involvement in the NICU. This tool serves several key purposes: to track the progression and timing of parents’ autonomy in caring for their baby, to support parents in building caregiving competencies before discharge, and to standardize the approach of NICU professionals in promoting both infant care and family engagement. Methods: A structured template form for documenting parental involvement (“together TO-CARE template”, TTCT) was integrated into the computerized chart adopted in the NICU of Modena. Nurses were asked to complete the TTCT at each shift. The template included the following assessment items: parental presence; type of contact with the baby (touch; voice; skin-to-skin); parental involvement in care activities (diaper changing; gavage feeding; bottle feeding; breast feeding); and level of autonomy in care (observer; supported by nurse; autonomous). We evaluated TTCT uploaded data for very low birth weight (VLBW) preterm infants admitted in the Modena NICU between 1 January 2023 and 31 December 2024. Staff compliance in filling out the TTCT was assessed. The timing at which parents achieved autonomy in different care tasks was also measured. Results: The TTCT was completed with an average of one entry per day, during the NICU stay. Parents reached full autonomy in diaper changing at a mean of 21.1 ± 15.3 days and in bottle feeding at a mean of 48.0 ± 22.4 days after admission. The mean length of hospitalization was 53 ± 38 days. Conclusions: The adoption of the TTCT in the NICU is feasible and should become a central component of care for preterm infants. It promotes family-centered care by addressing the needs of both the baby and the family. Encouraging early and progressive parental involvement enhances parenting skills, builds confidence, and may help reduce post-discharge complications and readmissions. Furthermore, the use of a standardized template aims to foster consistency among NICU staff, reduce disparities in care delivery, and strengthen the support provided to families of preterm infants. Full article

Background/Objective: In-hospital cardiac arrest has high incidence and poor survival rates, posing a significant healthcare challenge. It is important to intervene in the hours before the cardiac arrest to prevent poor outcomes. The modified early warning score (MEWS) is a validated tool for identifying a deteriorating patient. It is an aggregate of vital signs and level of consciousness. We retrospectively evaluated MEWS for trends that might predict patient outcomes. Methods: We performed a single-center, one-year, retrospective study. A comprehensive review was conducted for patients aged 18 years and above who experienced a cardiac arrest. Cases that occurred within an intensive care unit, emergency department, during a procedure, or outside the hospital were excluded. A total of 87 cases met our predefined inclusion criteria. We collected data at 12 h, 6 h and 1 h time periods prior to the cardiac arrest. A trend analysis using a linear model with analysis of variance with Bonferroni correction was performed. Results: Out of 87 patients included in the study, 59 (67.8%) had an immediate return of spontaneous circulation (ROSC). Among those who achieved ROSC, 41 (69.5%) died during the admission. Only 20.7% of the patients that sustained a cardiac arrest survived to discharge. A significant increase in the average MEWS was noted from the 12 h period (MEWS = 3.95 ± 2.4) to the 1 h period (MEWS = 5.98 ± 3.5) (p ≤ 0.001) and the 6 h period (4.65 ± 2.6) to the 1 h period (5.98 ± 3.5) (p = 0.023) prior to cardiac arrest. Conclusions: An increase in the MEWS may be a valuable tool in identifying at-risk patients and provides an opportunity to intervene at least 6 h before a cardiac arrest event. Further research is needed to validate the results of our study. Full article

This study presents a topology optimization approach to enhance the discharging performance of a latent heat thermal energy storage (LHTES) system using paraffin wax as the phase-change material (PCM) and a high-conductivity aluminium structure. Solidification is primarily governed by conduction, and the average heat transfer rate during this process is significantly lower than during melting; therefore, the optimization focused on the discharge phase. In a previous study, a novel LHTES device based on a Cartesian lattice was investigated experimentally and numerically. The validated numerical model from that study was adopted as the reference and used in a 2D topology optimization study based on the Solid Isotropic Material with Penalization (SIMP) method. The objective was to promote more uniform temperature distribution and reduce discharging time while maintaining the same aluminium volume fraction as in the reference device. Topology optimization produced a branched fin design, which was then extruded into a 3D model for comparison with the reference geometry. The optimized design resulted in improved temperature uniformity and a faster solidification process. Specifically, the time required to solidify 90% of the PCM was reduced by 12.3%, while the time to release 90% of the latent heat during the solidification process improved by 7.6%. Full article

Background: COVID-19-associated coagulopathy (CAC) is a complex condition, with high rates of thrombosis, high levels of inflammation markers and hypercoagulation (increased levels of fibrinogen and D-Dimer), as well as extensive microthrombosis in the lungs and other organs of the deceased. It resembles, without being identical, other coagulation disorders such as sepsis-DIC (SIC/DIC), hemophagocyte syndrome (HPS) and thrombotic microangiopathy (TMA). Platelets (PLTs), key regulators of thrombosis, inflammation and immunity, are considered an important risk mediator in COVID-19 pathogenesis. Platelet index MPV/PLT ratio is reported in the literature as more specific in the prognosis of platelet-related systemic thrombogenicity. Studies of MPV/PLT ratio with regards to the severity of COVID-19 disease are limited, and there are no references regarding this ratio to the outcome of COVID-19 disease at specific time points of hospitalization. The aim of this study is to evaluate the relationship of COVID-19 mortality with the red cell distribution width–coefficient of variation (RDW-CV), platelets and MPV/PLT ratio parameters. Methods: Values of these parameters in 511 COVID-19 hospitalized patients were recorded (a) on admission, (b) as mean values of the 1st and 2nd week of hospitalization, (c) over the total duration of hospitalization, (d) as nadir and zenith values, and (e) at discharge. Results: As for mortality (survivors vs. deceased), statistical analysis with ROC curves showed that regarding the values of the parameters on admission, only the RDW-CV baseline was of prognostic value. Platelet parameters, absolute number and MPV/PLT ratio had predictive potential for the disease outcome only as 2nd week values. On the contrary, with regards to disease severity (mild/moderate versus severe/critical), only the MPV/PLT ratio on admission can be used for prognosis, and to a moderate degree. On multivariable logistic regression analysis, only the RDW-CV mean hospitalization value (RDW-CV mean) was an independent and prognostic variable for mortality. Regarding disease severity, the MPV/PLT ratio on admission and RDW-CV mean were independent and prognostic variables. Conclusions: RDW-CV, platelets and MPV/PLT ratio hematological parameters could be of predictive value for mortality and severity in COVID-19 disease, depending on the hospitalization timeline. Full article

Background and Objectives: Acute appendicitis is a common surgical emergency, and while appendectomy typically results in good outcomes, post-operative complications, like intra-abdominal abscesses, can occur. Traditional biomarkers, such as white blood cells count and C-reactive protein, often lack the accuracy needed for early detection. Procalcitonin is emerging as a potential marker for predicting post-operative infections. This pilot study evaluates the role of kinetics of procalcitonin, measured via point-of-care testing, in predicting abscess formation in patients with non-complicated appendicitis. Materials and Methods: The study involved 33 patients undergoing appendectomy for non-complicated acute appendicitis. The levels of procalcitonin were measured at four time points: pre-operatively (T0), post-operatively (T1), on the first post-operative day (T2), and at discharge (T3). The primary outcome was the development of post-operative abscesses, confirmed by imaging or intervention. Results: Four patients (12%) developed abscesses. The levels of procalcitonin were significantly higher in the abscess group at all time points compared to the non-abscess group (p < 0.05). The levels of procalcitonin in the abscess group plateaued after an initial post-operative decline, while levels steadily decreased in the non-abscess group. Conclusions: Procalcitonin, particularly its kinetic profile, may serve as a valuable early marker for predicting post-operative abscess formation. Point-of-care testing for procalcitonin can enable timely intervention, improving outcomes. Kinetics of procalcitonin show promise as a predictor for post-operative abscesses after appendectomy, though larger studies are needed to confirm these findings. Full article

The corrosion behavior and electrochemical performance of Mg-La-Zr and Mg-La alloys were studied. Microstructural observation indicated that the trace alloying of Zr refined the grain size of Mg-La alloy, which improved the discharge activity of Mg-La alloys. At the same time, the addition of Zr led to a transformation of the second-phase distribution from intracrystalline to grain boundary central distribution. This change inhibited the self-corrosion of the alloy during discharge and improved the anode utilization efficiency. Therefore, an air battery based on a Mg-La-Zr alloy anode with a unique microstructure demonstrated a high discharge performance. In this paper, the relationship between the microstructure and anodic properties of Mg-La-Zr alloy are systematically elucidated. Full article

In our study, supercapacitor electrodes were prepared by depositing electroless Ni-B coating on copper plates, followed by nitric acid etching. The composition and the micro- and phase structure of the coatings were investigated by ICP-OES, PFIB-SEM, and XRD techniques. The original pebble-like structure of the coating consists of 0.8–10 µm particles, with an X-ray amorphous phase structure. The surface morphology and porosity of the coating can be tuned simply by changing the etching time. The supercapacitive performance of the electrodes was evaluated by means of cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy measurements. The capacitance of the coating was found to vary on the etching time according to a maximum function, allowing for the determination of an optimal duration to obtain a specific capacitance of 157 mF/cm² (at 0.5 A/g). An excellent charge storage retention of 178% was found after 5000 CV cycles at a scan rate of 50 mV/s owing to the evolved electrochemically active network on the surface of the electrode, indicating a long-term stable and reliable electrode. Full article

Selecting an appropriate model for discharge simulation remains a fundamental challenge in modeling. While artificial neural networks (ANNs) have been widely accepted due to detecting streamflow patterns, they require large datasets for efficient training. However, when short-term datasets are available, training ANNs becomes problematic. Autoregressive integrated moving average (ARIMA) models offer a promising alternative; however, severe volatility, nonlinearity, and trends in hydrological time series can still lead to significant errors. To address these challenges, this study introduces a new adaptive hybrid model, ARIMA-iGARCH, designed to account volatility, variance inconsistency, and nonlinear behavior in short-term hydrological datasets. We apply the model to four hourly discharge time series from the Schwarzbach River at the Nauheim gauge in Hesse, Germany, under the assumption of normally distributed residuals. The results demonstrate that the specialized parameter estimation method achieves lower complexity and higher accuracy. For the four events analyzed, R² values reached 0.99, 0.96, 0.99, and 0.98; RMSE values were 0.031, 0.091, 0.023, and 0.052. By delivering accurate short-term discharge predictions, the ARIMA-iGARCH model provides a basis for enhancing water resource planning and flood risk management. Overall, the model significantly improves modeling long memory, nonlinear, nonstationary shifts in short-term hydrological datasets by effectively capturing fluctuations in variance. Full article

With the increasing integration of renewable energy sources (RESs) into power systems, batteries are playing a critical role in ensuring grid reliability and flexibility. Among them, vanadium redox flow batteries (VRFBs) have emerged as a promising solution for large-scale storage due to their long cycle life, scalability, and deep discharge capability. However, achieving optimal control and system-level integration of VRFBs requires accurate, real-time modeling and parameter estimation, challenging tasks given the multi-physics nature and time-varying dynamics of such systems. This paper presents a lightweight physics-informed neural network (PINN) framework tailored for VRFBs, which directly embeds the discrete-time state-space dynamics into the network architecture. The model simultaneously predicts terminal voltage and estimates five discrete-time physical parameters associated with RC dynamics and internal resistance, while avoiding hidden layers to enhance interpretability and computational efficiency. The resulting PINN model is integrated into a modulated model predictive control (MMPC) scheme for a dual-stage DC-AC converter interfacing the VRFB with low-voltage AC grids. Simulation and hardware-in-the-loop results demonstrate that adaptive tuning of the PINN-estimated parameters enables precise tracking of battery parameter variations, thereby improving the robustness and performance of the MMPC controller under varying operating conditions. Full article

Background/Objectives: Breastmilk offers numerous benefits for the health and development of preterm infants, while prolonged hospitalization may impair neurodevelopment. At our institution, the implementation of enhanced family-centered care (FCC) has enabled earlier discharge of preterm infants. This study aimed to assess the impact of early discharge on breastfeeding and breastmilk provision. Methods: This analysis is based on data from a prospective single-center longitudinal cohort study conducted from October 2020 to November 2023, involving six consecutive cohorts (one baseline and five intervention cohorts; n = 184). FCC was progressively enhanced across cohorts. The primary outcome of the main study was postmenstrual age (PMA) at discharge. In this secondary analysis, breastfeeding and breastmilk provision were assessed at four time points: 4 weeks postnatal age, at discharge, 4 weeks post-discharge, and at 3 months PMA. Results: From baseline to intervention cohort 5, the PMA at discharge declined significantly from 37.8 ± 2.1 to 35.7 ± 0.91 weeks (p = 0.03), while the percentage of infants necessitating home nasogastric tube feeding increased from 6.3% to 66.7% (p < 0.01). The proportion of breastmilk of daily feeding volume remained unchanged at 4 weeks postnatal age (0.66 ± 0.42 vs. 0.9 ± 0.28) and at discharge (0.6 ± 0.45 vs. 0.79 ± 0.36). At 4 weeks post-discharge, 65.8% vs. 62.5% of the infants were on partial or exclusive breastmilk (p = 0.91) feeding. Similarly, the percentage of exclusively breastfed infants at 4 weeks post-discharge (23.7% vs. 19.8%) and at 3 months PMA (20% vs. 28.6%) did not differ significantly between baseline and intervention cohort 5. Conclusions: Early discharge did not reduce breastmilk supply or exclusive breastfeeding. However, the persistently low rate of exclusive breastfeeding post-discharge highlights the need for additional support strategies during and after hospitalization. Full article

Spontaneous quadriceps tendon rupture is a very rare occurrence, notably for bilateral simultaneous ruptures. Its occurrence is commonly linked to an underlying condition that may weaken the tendons leading to rupture. We report the case of a 68-year-old Caucasian male afflicted with long-term gout who presented a bilateral simultaneous quadriceps tendon rupture (BSQTR). We showcase the clinical presentation, the surgical intervention, rehabilitation program, dynamic sonographic monitoring, and home-based rehabilitation techniques of this injury, which aimed to improve activities of daily living (ADL) and quality of life (QoL). The patient was included in a 9-week post-surgical rehabilitation program and a home-based rehabilitation program with subsequent pain management and gait reacquisition. The outcome measures included right and left knee active range of motion (AROM), pain intensity measured on Visual Analogue Scale (VAS), functioning measured through ADL score, and gait assessment on Functional Ambulation Categories (FAC). All endpoints were measured at different time points, scoring significant improvement at discharge compared to baseline (e.g., AROM increased from 0 degrees to 95 degrees, while VAS decreased from 7 to 1, ADL score increased from 6 to 10, and FAC increased from 1 to 5). Moreover, some of these outcomes continued to improve after discharge, and the effects of home-based rehabilitation program and a single hip joint manipulation were assessed at 6-month follow-up. Musculoskeletal ultrasound findings showed mature tendon structure, consistent dynamic glide, and no scarring. Full article

Background: Diabetes mellitus is a chronic metabolic disorder that increases mortality and morbidity rates. Infections of the hand can easily cause long-term morbidity and dysfunction, but despite their associated high morbidity, diabetic hand infections are more neglected than diabetic foot infections. Objectives: This study was conducted over a one-year follow-up period, considering the total costs of treatment over one year post discharge for patients with diabetic hand infections that required surgery. A Monte Carlo Simulation was used in this study as a sensitivity analysis of all the cost calculations. Materials and Methods: A total of 62 out of 75 patients were diagnosed with Type 2 diabetes; 11 were female, and 64 were male. Out of all the patients, 15 visited outpatient clinics 30 times or more, and due to their recurrent visits, the outpatient treatment costs reached USD 5162.41 ± 3838.55. The total cost incurred over the period from the patients’ first hospitalization to the completion of all treatments and the end of the one-year follow-up was USD 24,602.22 ± 5257.15. Conclusions: The cost of hospitalization was the most important factor affecting the total expenses. Therefore, taking precautions before a diabetic hand infection occurs, or when one does occur, performing treatment without delay is expected to reduce the economic burden. Full article

Objective: Potassium levels (KLs) influence clinical outcomes in severe traumatic brain injury (TBI). This study investigates the relationship between KLs and clinical outcomes to improve prognosis and guide management. Method: A retrospective study was conducted at a level 1 trauma center in Queens, New York, from January 2020 to December 2023. Patients with an AIS score of 3 or higher were included. KLs were measured at the time of hospital admission, ICU admission, ICU discharge, hospital discharge, and death, if applicable. Clinical outcomes such as age, race, length of hospital stay (H LOS), ICU length of stay (ICU LOS), ventilation days (VDs), Glasgow Coma Scale (GCS), and mortality were assessed. Results: KLs were categorized into five groups: extreme hypokalemia (<2.5 mEq/L), hypokalemia (2.6–3.5 mEq/L), normokalemia (3.5–5.2 mEq/L), hyperkalemia (5.2–7.0 mEq/L), and extreme hyperkalemia (>7.0 mEq/L). Significant correlations were observed between KLs at hospital admission and age (p = 0.0113), race (p = 0.003), and H LOS (p = 0.079). ICU KLs showed positive correlations with AIS head score (p = 0.038), ISS (p = 7.84 × 10⁻⁶), and GCS (p = 2.6 × 10⁻⁶). ICU KLs were also associated with LOS in the Emergency Department (ED) (p = 6.875 × 10⁻⁶) and ICU (p = 1.34 × 10⁻²¹), as well as VDs (p = 7.19 × 10⁻⁷). ICU discharge KLs correlated with ISS (p = 2.316 × 10⁻³), GCS (p = 2.201 × 10⁻³), ED LOS (p = 3.163 × 10⁻⁴), and VDs (p = 7.44 × 10⁻⁴). KLs at discharge were linked with mortality (p < 0.0001) and H LOS (p = 0.0091). Additionally, KLs at the time of death were correlated with ISS (p = 0.01965), GCS (p = 0.01219), ED LOS (p = 0.00594), ICU LOS (p = 0.049), VDs (p = 0.00005), and mortality (p < 0.0001). Conclusions: Potassium imbalances, especially hypokalemia, significantly affect outcomes in severe TBI patients. Monitoring and managing KLs may improve prognosis. Full article

The converter transformer is subjected to AC/DC composite voltage during operation, and the sealed and time-varying internal state makes its electric field distribution and charge accumulation unable to be monitored in real-time experiments. In this paper, aiming at the influence of bubbles in the oil passage of the converter transformer on charge accumulation before discharge, a simulation model in a laminar flow environment is established, and four different calculation conditions are set to simulate the charge accumulation in 1 s. It is found that under laminar flow conditions, the trapped bubbles on the insulation paper wall play an obvious role in intensifying the charge accumulation in transformer oil, and the extreme range of charge density will increase by about 10⁴ times. Bubbles aggravate the electric field distortion, and the insulation strength of bubbles is lower, which becomes the weak link of insulation. In the laminar flow environment, the oil flow will take away part of the accumulated charge in the oil, but in the case of trapped bubbles, the charge accumulation in the insulating paper will increase from the order of 10⁻² to 10⁻¹. In the case of no bubbles, the transformer oil layer flow will increase the charge accumulation in the insulation paper by 4–5 orders of magnitude. Therefore, it can be seen that the flow of transformer oil will increase the deterioration level of insulation paper. And when the transformer oil is already in the laminar flow state, the influence of laminar flow velocity on charge accumulation is not obvious. The research results in this paper provide a time-varying simulation reference state for the charge accumulation problem that cannot be measured experimentally under normal charged operation conditions, and we obtain quantitative numerical results, which can provide a valuable reference for the study of transformer operation and insulation discharge characteristics. Full article