Search Results (1,485,236)

This study evaluates the impact of the addition of nanoparticles of anodic manganese dioxide (NAMD) on the mechanical properties and resistance to chemical attack of concrete. The research focused on nine concrete mixtures with water/cement ratios of 0.40, 0.45, and 0.50 and NAMD contents of 0, 5, and 10%. The properties of NAMD were analyzed, and fresh concrete properties such as temperature, unit weight, and consistency were measured. The compressive strength was determined at different ages (7, 14, 28, 56, and 90 days). The tensile and flexural strength were evaluated at 28 days, and the longitudinal change generated by the SO₄Mg attack was monitored until 90 days. In addition, an accelerated carbonation test was performed on concrete samples with 28 days of curing exposed to an atmosphere of 6% CO₂ for one week. The addition of NAMD did not significantly affect the temperature or unit weight of the fresh concrete, but it did influence the consistency. An increase in compressive, tensile, and flexural strength was observed, especially at early ages and for low w/c ratios. The addition of NAMD reduced the expansion of concrete exposed to magnesium sulfate, with 5% being the most effective dose, and reduced the carbonation rate of concrete by up to 40% in mixes with w/c ratios of 0.40 and 0.50. It was shown that the addition of 5% as an effective dose of NAMD improves the mechanical and durability properties of concrete, especially in mixtures with a low water/cement ratio, contributing to the improvement of the quality and strength of concrete. Full article

Fluoride treatment of ZSM-5 zeolite can effectively adjust surface acidity and generate a secondary pore structure. In this study, a series of modified nano-HZSM-5 zeolites were prepared by NH₄F-HF mixed solution treatment and applied to the selective conversion of bioethanol to propylene at 500 °C, atmospheric pressure, and a WHSV of 10 h⁻¹. The results showed that NH₄F-HF modification weakened the surface acidity of nano-HZSM-5 zeolites, thus inhibiting coke formation. Additionally, the mesopores in the nano-HZSM-5 zeolites increased after NH₄F-HF treatment, thereby enhancing the mass transfer rate and improving the coke-resistance ability. The NH₄F-HF mixed solution modification significantly improved the stability of nano-HZSM-5 zeolites in catalyzing bioethanol to propylene and greatly extended the working life of nano-HZSM-5 zeolites. It can be seen from the characterization of the deactivated catalysts that coke deposition and weakening of acidity may be the key factors for catalyst deactivation. Full article

Background/Objectives: Uvulopalatopharyngoplasty (UPPP), palatal plus nasal surgery (PNS), and continuous positive airway pressure (CPAP) are widely implemented treatments for obstructive sleep apnea (OSA). This study aims to explore the long-term effects on objective sleep parameters and patient-reported outcomes (PROs) following different therapeutic interventions for OSA. Methods: Data from patients with moderate-to-severe OSA were retrospectively collected from a medical center and a regional hospital, spanning from December 2011 to August 2018. Objective evaluations included the Apnea–Hypopnea Index (AHI), minimum O₂ saturation, and sleep efficiency. The PROs consisted of the Snore Outcomes Survey and Epworth Sleepiness Scale. Using mixed-effects models, we evaluated longitudinal changes in sleep parameters and PROs, accounting for repeated measures and variations within individuals over time. Results: Among 448 patients with moderate-to-severe OSA, follow-up data were collected for 42 patients undergoing UPPP surgery, 171 undergoing PNS, 127 using CPAP, and 108 in the non-treated group. The mean follow-up was 16.7 months (SD = 11.9, range: 1.6–77.3). Significant improvements were observed in AHI, minimum O₂ saturation, and hypersomnia immediately following interventions with UPPP, PNS, and CPAP therapy (p < 0.05). Moreover, the analysis revealed no significant rate of change in these parameters over time, suggesting that the benefits of these treatments were sustained in the long term. Furthermore, all interventions exhibited a significant short-term effect on self-reported snoring when compared to the control group, with a p-value of less than 0.001. However, the magnitude of this improvement gradually decreased over time. The snore scores seemed to return to pre-treatment levels among the UPPP, PNS, and CPAP groups after averages of 46.4, 63.5, and 74.4 months, respectively (all p < 0.05). Conclusions: Surgical interventions and CPAP therapy showed potential long-term effectiveness in managing OSA. Snoring symptoms reappeared about 3.9–5.3 years after surgical treatments, which seemed earlier than the average of 6.2 years in patients receiving CPAP and should be considered in patient-participatory decision-making processes. Full article

Background: The definition of alcohol hangovers refers to a combination of mental and physical side effects that occur after drinking. One of the ways that hangovers can be ameliorated is by promoting the rapid and effective elimination of acetaldehyde to alleviate the discomfort it causes. This study aimed to investigate the effects of GSH (yeast extract containing 50 mg of glutathione) on the hangover-relieving effect. Methods: A randomized double-blind placebo-controlled crossover clinical trial was conducted with 40 participants who reported experiencing hangover symptoms. Participants consumed alcohol at a rate of 0.78 g per kg body weight with 40% whiskey, adjusted according to their weight. Alcohol and acetaldehyde concentrations in serum were analyzed at 0, 0.25, 1, 2, 4, 6, and 15 h after alcohol consumption. Results: In the GSH group, the serum alcohol concentration decreased, although this change was not statistically significant. The serum acetaldehyde concentration was significantly lower in the GSH group in comparison to the placebo group (at 0.25, 1, 4, and 6 h (p < 0.01) and at 0.5, 2, and 15 h (p < 0.001) after alcohol consumption). However, there was no significant difference between the two groups on questionnaires such as the Acute Hangover Scale and the Alcohol Hangover Severity Scale. Conclusions: Overall, we consider the discovery that GSH lowered acetaldehyde concentration, a crucial factor in alcohol metabolism, to be more considerable. Therefore, GSH administration effectively reduces acetaldehyde levels in serum. This result suggests that this effect may contribute to the relief of hangover symptoms. Full article

Studying rotor-bearing systems involving fluid film bearings is essential for designing and assessing the dynamic responses and performance of rotating machinery. They are involved in many applications such as pumps, turbines, and engines. Water-lubricated bearings are often used in many applications where the use of oil-based lubricants is not desirable, such as in environmentally sensitive areas such as water desalination. In this study, dynamic analysis is performed to identify the stability regions that prevent the application of water-lubricated journal bearings. This is achieved by solving the system equations of motion and then using an infinitesimal perturbation method to evaluate the second-order bearing coefficients of a journal bearing. In this paper, a steel shaft supported by two symmetrical journal bearings was used to investigate the system stability analysis. A test rig is designed and manufactured to examine the rotor’s dynamic behavior and verify the theoretical outcomes of the FE model, utilizing the bearing coefficients based on second-order analysis. Furthermore, this study compares the two fluids, both theoretically and experimentally, investigating their impact on the rotor-bearing system at different rotational speeds. The theoretical findings indicate that the threshold speed for journal bearings is significantly higher when using water as the lubricant fluid film compared to using oil as the lubricant fluid. Additionally, because of the low viscosity of water, water-lubricated bearings are susceptible to significant wear and noise in operating conditions. Our experiments show that an oil lubricant provides less response than a water lubricant for unbalanced rotors within the tested speed range. Full article

Small berries are rich sources of bioactive compounds, acknowledged for a wide variety of biological activities. The health benefits of these berries are primarily attributed to phenolic compounds, such as phenolic acids, flavonoids, and tannins, owing to their good antioxidant capacity, anti-inflammatory, anticancer, and neuro- and cardioprotective properties. In order to compensate for the lack of fresh fruit availability throughout the year, berries are usually processed to obtain various final products. Depending on the processing condition, the nutritional and functional profile of the berries might be affected. The present review focuses on the bioactive compounds with antioxidant activity that contribute to the health-related properties of berries and on the effects of the conventional and alternative thermal and non-thermal techniques employed for processing berries into final products. The literature suggests that, regardless of the processing method, incorporating berries into the daily diet offers protective and preventive benefits against various diseases. Full article

A visual workload model was constructed to determine and evaluate drivers’ visual workload characteristics in high-density interchange-merging areas. Five interchanges were selected, and a real-vehicle driving test was conducted with 47 participants. To address the differences in drivers’ visual characteristics in the interchange cluster merging areas, the Criteria Importance Through Intercriteria Correlation (CRITIC) objective weighting method was employed. Six visual parameters were selected to establish a comprehensive evaluation model for the visual workload in high-density interchange-merging areas. The results show that the average scanning frequency and average pupil area change rate are most strongly correlated with the visual workload, whereas the average duration of a single gaze has the lowest weight in the visual workload assessment system. Different driver visual workloads were observed depending on the environment of the interchange-merging areas, and based on these, recommendations are proposed to decrease drivers’ workload, thereby increasing road safety. Full article

Microbes have inhabited the earth for hundreds of millions of years longer than humans. The microbiota–gut–brain axis (MGBA) represents a bidirectional communication pathway. These communications occur between the central nervous system (CNS), the enteric nervous system (ENS), and the emotional and cognitive centres of the brain. The field of research on the gut–brain axis has grown significantly during the past two decades. Signalling occurs between the gut microbiota and the brain through the neural, endocrine, immune, and humoral pathways. A substantial body of evidence indicates that the MGBA plays a pivotal role in various neurological diseases. These include Alzheimer’s disease (AD), autism spectrum disorder (ASD), Rett syndrome, attention deficit hyperactivity disorder (ADHD), non-Alzheimer’s neurodegeneration and dementias, fronto-temporal lobe dementia (FTLD), Wilson–Konovalov disease (WD), multisystem atrophy (MSA), Huntington’s chorea (HC), Parkinson’s disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), temporal lobe epilepsy (TLE), depression, and schizophrenia (SCZ). Furthermore, the bidirectional correlation between therapeutics and the gut–brain axis will be discussed. Conversely, the mood of delivery, exercise, psychotropic agents, stress, and neurologic drugs can influence the MGBA. By understanding the MGBA, it may be possible to facilitate research into microbial-based interventions and therapeutic strategies for neurological diseases. Full article

This study presents a comprehensive analysis on the variations in the tropical cyclone (TC) frequencies during 1980–2021, including the linear trends, periodicities, and their variabilities on both global and basin-wise scales. An increasing trend in the annual number of global TCs is identified, with a significant rising trend in the numbers of tropical storms (maximum sustained wind ) and intense typhoons () and a deceasing trend for weak typhoons (). There is no statistically significant trend shown in the global Accumulated Cyclone Energy (ACE). On a regional scale, the Western North Pacific (WNP) and Eastern North Pacific (ENP) are the regions of the first- and second-largest numbers of TCs, respectively, while the increased TC activity in the North Atlantic (NA) contributes the most to the global increase in TCs. It is revealed in the wavelet transformation for periodicity analysis that the variations in the annual number of TCs with different intensities mostly show an inter-annual period of 3–7 years and an inter-decadal one of 10–13 years. The inter-annual and inter-decadal periods are consistent with those in the ENSO-related ocean drivers (via the Niño 3.4 index), Southern Oscillation Index (SOI), and Inter-decadal Pacific Oscillation (IPO) index. The inter-decadal variation in 10–13 years is also observed in the North Atlantic Oscillation (NAO) index. The Tropical North Atlantic (TNA) index and Atlantic Multi-decadal Oscillation (AMO) index, on the other hand, present the same inter-annual period of 7–10 years as that in the frequencies of all the named TCs in the NA. Further, the correlations between TC frequencies and ocean drivers are also quantified using the Pearson correlation coefficient. These findings contribute to an enhanced understanding of TC activity, thereby facilitating efforts to predict particular TC activity and mitigate the inflicted damage. Full article

Background/Objectives: Routine postoperative ICU admission following brain tumor surgery may not benefit selected patients. The objective of this study was to develop a risk prediction instrument for early (within 24 h) postoperative adverse events using machine learning techniques. Methods: Retrospective cohort of 1000 consecutive adult patients undergoing elective brain tumor resection. Nine events/interventions (CPR, reintubation, return to OR, mechanical ventilation, vasopressors, impaired consciousness, intracranial hypertension, swallowing disorders, and death) were chosen as target variables. Potential prognostic features (n = 27) from five categories were chosen and a gradient boosting algorithm (XGBoost) was trained and cross-validated in a 5 × 5 fashion. Prognostic performance, potential clinical impact, and relative feature importance were analyzed. Results: Adverse events requiring ICU intervention occurred in 9.2% of cases. Other events not requiring ICU treatment were more frequent (35% of cases). The boosted decision trees yielded a cross-validated ROC-AUC of 0.81 ± 0.02 (mean ± CI95) when using pre- and post-op data. Using only pre-op data (scheduling decisions), ROC-AUC was 0.76 ± 0.02. PR-AUC was 0.38 ± 0.04 and 0.27 ± 0.03 for pre- and post-op data, respectively, compared to a baseline value (random classifier) of 0.092. Targeting a NPV of at least 95% would require ICU admission in just 15% (pre- and post-op data) or 30% (only pre-op data) of cases when using the prediction algorithm. Conclusions: Adoption of a risk prediction instrument based on boosted trees can support decision-makers to optimize ICU resource utilization while maintaining adequate patient safety. This may lead to a relevant reduction in ICU admissions for surveillance purposes. Full article

Bladder cancer (BC) is one of the most common malignant neoplasms of the genitourinary system. Traditional BC therapies include chemotherapy, targeted therapy, and immunotherapy. However, limitations such as lack of specificity, cytotoxicity, and multidrug resistance pose serious challenges to the benefits of BC therapies. Consequently, current studies focus on the search for new therapeutic solutions. In recent years, there has been a growing interest in using nanotechnology in the treatment of both non-invasive (NMIBC) and invasive bladder cancer (MIBC). Nanotechnology is based on the use of both organic molecules (chitosan, liposomes) and inorganic molecules (superparamagnetic iron oxide nanoparticles) as carriers of active substances. The main aim of such molecules is the targeted transport and prolonged retention of the drug in the target tissue, which increases the therapeutic efficacy of the active substance. This review discusses the numerous types of nanoparticles (including chitosan, polymeric nanoparticles, liposomes, and protein nanoparticles), targeting mechanisms, and approved nanotherapeutics with oncological implications in cancer treatment. We also present nanoformulation applications in phototherapy, gene therapy, and immunotherapy. Moreover, we summarise the current perspectives, advantages, and challenges in clinical translation. Full article

Objectives: To review the evidence on the clinical value of magnetic source imaging (MSI) in patients with refractory focal epilepsy without evidence for an epileptogenic lesion on magnetic resonance imaging (“MRI-negative” or “non-lesional MRI”). Methods: We conducted a systematic literature search on PUBMED, which was extended by researchrabbit.ai using predefined criteria to identify studies that applied MSI in MRI-negative patients with epilepsy. We extracted data on patient characteristics, MSI methods, localization results, surgical outcomes, and correlation with other modalities. Results: We included 23 studies with a total of 512 non-lesional epilepsy patients who underwent MSI. Most studies used equivalent current dipole (ECD) models to estimate the sources of interictal epileptic discharges (IEDs). MEG detected IEDs in 32–100% of patients. MSI results were concordant with other modalities, such as EEG, PET, and SPECT, in 3892% of cases. If MSI concordant surgery was performed, 52–89% of patients achieved seizure freedom. MSI contributed to the decision-making process in 28–75% of cases and altered the surgical plan in 5–33% of cases. Conclusions: MSI is a valuable diagnostic tool for MRI-negative patients with epilepsy, as it can detect and localize IEDs with high accuracy and sensitivity, and provides useful information for surgical planning and predicts outcomes. MSI can also complement and refine the results of other modalities, such as EEG and PET, and optimize the use of invasive recordings. MSI should be considered as part of the presurgical evaluation, especially in patients with non-lesional refractory epilepsy. Full article

Making cities resilient and secure remains a central goal in urban policy strategies, where established methods, technologies, and best experiences are applied or replicated when the knowledge of a threat is already well established. The scientific community and specialized bodies are invited to comprehend and evaluate disastrous events that are still not well explored to broaden the concept of resilient cities. Among these, terrorism in the European-built environment remains an underexplored topic, despite various studies assessing its economic, social, and political dimensions, exploring the radicalist matrix, or examining the post-effects of high-impact disastrous events. Within this framework, this work presents an algorithm for the risk assessment of historic urban open areas (uOAs) in Europe, combining theories of the terrorism phenomenon, the normative experiences, and the phenomenological results of violent acts in uOAs. Specifically, the algorithm is determined by studying physical qualities/properties and elements that usually feature the uOAs, using a limited set of descriptors. The descriptors and their formulation are set starting from their qualification, in compliance with the risk determinant (Hazard, Vulnerability, and Exposure), and discussed starting from participatory methods (Delphi and AHP). The algorithm is finally applied to Italian historic squares, testing the mathematical approach, verifying theories of the phenomenon, and setting up a comprehensive three-dimensional risk matrix for both soft and hard targets. This latest constitutes an operative tool to assess the investigated built environment exposed to terrorist threats aimed at developing more detailed mitigative strategies. Full article

Through a three-factor, two-level orthogonal experiment, the effects of varying electrical parameters (voltage, frequency, and duty cycle) on the thickness, pressure resistance, corrosion resistance, morphology, and phase composition of the micro-arc oxidized film of aluminum foil in constant voltage mode were investigated. The aluminum foil was oxidized by micro-arc oxidation for 50 min. Eddy-current thickness gauges were used to measure the oxide film’s thickness, TV characterization testers were used to test the film’s resistance to pressure, kinetic potential polarization curves were used to examine the oxide film’s resistance to electrochemical corrosion, and SEM and XRD composition were used to examine the microstructures and phase compositions of the oxide films that were produced. The oxide film’s thickness was increased from 7 μm to 22 μm and the voltage was increased from 350 V to 450 V. The oxide film’s ramp-up time at a frequency and duty cycle of 2000 Hz and 15% could reach 3 s, and the resistance value could reach 98% of the micro-arc oxidation voltage. The oxide film’s i_corr decreased by an order of magnitude at high voltage compared to low voltage and the R_p value increased by an order of magnitude, which improved the corrosion resistance. The oxide film’s thickness increased as the voltage increased. Meanwhile, SEM was used to enhance the corrosion resistance. The oxide film thickens as the voltage increases. At the same voltage, the oxide film with a high frequency and low duty cycle has the best voltage resistance. The oxide film generated under high-voltage conditions has regular and dense surface holes, the oxide film’s α-Al₂O₃ phase increases, and the corrosion resistance in the NaCl medium is enhanced. Full article

Skin shrinkage begins immediately after surgical incision and is an artefact associated with the excision and fixation of a specimen. Skin shrinkage results in important changes in histologic tissue dimensions and can affect the correct quantification of the histologic tumour-free margin (HTFM). Bilateral and symmetrical circular skin samples with a diameter of 60 mm were taken from the lateral thoracic, flank and femoral regions of dog cadavers, with the samples from one side belonging to the study group and the samples from the same animal from the other side belonging to the control group. The radius and diameter of the specimen were measured immediately after the excision and 10 min later for each sample. The measurements of the study group were taken again after manual re-extension and fixation on a cork plate before formalin fixation and 48 h after formalin fixation. A total of 66 (33 study and 33 control group) samples were collected from 11 canine cadavers. The mean diameter shrinkage after formalin fixation was 18.24% for the control group and 0.64% for the study group. A statistically significant difference between the study and the control group was found (p < 0.001). This method of specimen fixation in the study group avoided skin shrinkage and deformation of the specimen in formalin, which we believe improves the diagnostic accuracy of surgical margins and, thus, reduces the number of false-positive or false-negative HTFM. Full article