Search Results (112)

We investigate the statistical entropy of black holes within the framework of the generalized uncertainty principle (GUP) by employing effective metrics that incorporate leading-order and all-order quantum gravitational corrections. We construct three distinct effective metrics induced by the GUP, which are derived from the GUP-corrected temperature, entropy, and all-order GUP corrections, and analyze their impact on black hole entropy using ’t Hooft’s brick wall method. Our results show that, despite the differences in the effective metrics and the corresponding ultraviolet cutoffs, the statistical entropy consistently satisfies the Bekenstein–Hawking area law when expressed in terms of an invariant (coordinate-independent) distance near the horizon. Furthermore, we demonstrate that the GUP naturally regularizes the ultraviolet divergence in the density of states, eliminating the need for artificial cutoffs and yielding finite entropy even when counting quantum states only in the vicinity of the event horizon. These findings highlight the universality and robustness of the area law under GUP modifications and provide new insights into the interplay between quantum gravity effects and black hole thermodynamics. Full article

Background: Acute complicated cholecystitis (ACC) is associated with prolonged hospitalization, increased morbidity, and higher mortality. However, objective imaging-based criteria to guide early clinical decision-making remain limited. This study aimed to develop a predictive scoring system integrating clinical characteristics, laboratory biomarkers, and computed tomography (CT) findings to facilitate the early identification of ACC in the emergency department (ED). Methods: We conducted a retrospective study at an urban tertiary care center in Taiwan, screening 729 patients who presented to the ED with suspected cholecystitis between 1 January 2018 and 31 December 2020. Eligible patients included adults (≥18 years) with a confirmed diagnosis of acute cholecystitis based on the Tokyo Guidelines 2018 (TG18) and who were subsequently admitted for further management. Exclusion criteria included (a) the absence of contrast-enhanced CT imaging, (b) no hospital admission, (c) alternative final diagnosis, and (d) incomplete clinical data. A total of 390 patients met the inclusion criteria. Demographic data, laboratory results, and CT imaging features were analyzed. Logistic regression and decision tree analyses were used to construct predictive models. Results: Among the 390 included patients, 170 had mild, 170 had moderate, and 50 had severe cholecystitis. Key predictors of ACC included gangrenous changes, gallbladder wall attenuation > 80 Hounsfield units, CRP > 3 mg/dL, and WBC > 11,000/μL. A novel scoring system incorporating these variables demonstrated good diagnostic performance, with an area under the curve (AUC) of 0.775 and an optimal cutoff score of ≥2 points. Decision tree analysis similarly identified these four predictors as critical determinants in stratifying disease severity. Conclusions: This CT- and biomarker-based scoring system, alongside a decision tree model, provides a practical and robust tool for the early identification of complicated cholecystitis in the ED. Its implementation may enhance diagnostic accuracy and support timely clinical intervention. Full article

Introduction: The transforming growth factor beta (TGF-β) signaling pathway plays a critical role in cellular processes, including maintaining vascular integrity and regulating vascular remodeling. Aneurysm rupture is associated with pathological changes in the arterial wall. Aims: We aimed to investigate the gene expression of transforming growth factors (TGFB1, TGFB2, TGFB3) in peripheral blood mononuclear cells (PBMCs) isolated from the blood of patients with unruptured intracranial aneurysms (UIAs) and ruptured intracranial aneurysms (RIAs), and from a control group. Additionally, we evaluated serum levels of TGF-β1, TGF-β2, and TGF-β3 and analyzed their associations with various risk factors, including sex, age, aneurysm size, number, shape, smoking, and hypertension. Materials and Methods: The study group consisted of patients diagnosed with intracranial aneurysms (IAs) who were eligible for embolization at the Department of Neurosurgery, Clinical Hospital of the Medical University of Bialystok. The control group consisted of healthy volunteers, recruited from the employees of the Clinical Hospital of the Medical University of Bialystok. Expression levels were assessed using quantitative real-time polymerase chain reaction techniques in PBMCs. Serum concentrations of TGF-β isoforms were evaluated using a multiplexed bead-based immunoassay. Results: Among 32 patients, 24 had unruptured intracranial aneurysms (UIAs), including 18 women and 6 men, while 8 presented with ruptured intracranial aneurysms (RIAs), evenly distributed between women and men (4 each). The mean age of the patients was 53 years (range: 24–71 years). The control group consisted of 20 healthy volunteers, 14 females and 6 males, with a mean age of 51 years (range: 24–71 years). The expression of TGFB1 was significantly higher in the IA versus C group, but TGFB3 expression was significantly higher in the RIA versus C group. The serum level of TGF-β1 and TGF-β3 was significantly higher in the RIA versus UIA group. Serum TGF-β1 levels were higher in men and individuals < 60 years of age. Positive correlations were observed between serum TGF-β1, TGF-β3 and aneurysm size, with significantly higher TGF-β3 levels in patients with giant aneurysms. Conclusions: Our study highlights the distinct roles of TGFB1 and TGFB3 in aneurysm pathophysiology, identifying TGFB1 as a molecular contributor to aneurysm formation and TGFB3 with rupture. Increased serum TGF-β1 and TGF-β3 concentrations could serve as promising noninvasive parameters for assessing the risk of aneurysm rupture. Further research with larger cohorts is needed to define cut-off values and validate the method, enabling the use of blood TGF-β levels as a tool for clinical decision-making. Full article

Soil–bentonite (SB) vertical cut-off walls are widely utilized to mitigate the transport of soil contaminants in groundwater. Evaluating their long-term service performance is crucial for ensuring environmental safety and effective pollution control. The evaluation model for the long-term service performance of contaminant cut-off walls considers key processes such as convection, diffusion, dispersion, and adsorption. These processes are closely linked to the physicochemical properties of the cut-off walls, which are influenced by the surrounding complex environment, ultimately impacting their long-term performance. This study delves into the long-term service performance of SB vertical cut-off walls. It focuses on the key factors that influence this performance and the measures that can enhance it. Moreover, it offers a detailed analysis of how the performance of seepage cut-off walls in soil–bentonite materials evolves under various environmental influences. These influences include chemical exposure, freeze–thaw cycles, and dry–wet cycles. Additionally, it outlines existing service performance evaluation methods and identifies their shortcomings. By leveraging the advantages of in situ testing methods, this paper proposes the establishment of a comprehensive evaluation system for the service performance of vertical cut-off walls based on in situ test parameters. The proposed evaluation system aims to provide a scientific assessment of the long-term service performance of SB vertical cut-off walls. Full article

Slope stability analysis requires particular attention to groundwater effects, where seepage–stress coupling fundamentally alters mechanical responses. This investigation develops a field-calibrated numerical model using monitoring data from a water diversion project in Yunnan, using finite element analysis based on seepage–stress coupling theory. Comparative stability assessments through strength reduction methodology evaluate three scenarios: non-seepage conditions, seepage–stress interaction, and cutoff wall implementation. Results demonstrate the cutoff wall’s effectiveness, achieving optimal slope ratios of 1:1.41 compared to 1:2.21 under seepage–stress coupling. Parametric analyses reveal quantitative relationships between wall characteristics and stability metrics. Elastic modulus optimization within practical ranges (9362.63 MPa peak performance) enables steeper 1:1.37 slopes while maintaining safety factors. Strategic width reduction from 0.6 m to 0.4 m decreases concrete usage by 33% without compromising stability thresholds, proving cost-efficiency in large-scale applications. The methodology provides actionable guidelines for deep excavation projects facing similar hydrogeological challenges. Optimized cutoff walls enhance slope stability sustainably through ecological preservation and resource efficiency, providing actionable frameworks for eco-conscious geotechnical design aligned with global sustainability objectives. Full article

Cement–bentonite cut-off walls are widely used in geoenvironmental engineering such as landfill liners and contaminated site remediation, due to their low permeability and structural stability. However, excessive cement use reduces the swelling capacity of bentonite and increases environmental burdens. This study proposes incorporating polypropylene fibers (PPFs) into cement–bentonite cut-off walls to improve their performance under lower cement dosages. A total of 16 formulations were tested with different cement and fiber contents. Unconfined compressive strength (UCS), direct shear, and falling head permeability tests were conducted over 7, 14, and 28 days, respectively. Microstructural changes were examined using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that compared to the conventional high-cement mixture without fibers, a formulation with moderate cement content and 2% PPF achieved higher compressive strength, comparable shear strength, and significantly lower permeability. Microstructural analysis confirmed that fiber addition enhanced cement hydration and preserved bentonite, forming a compact microstructure with reduced porosity. Furthermore, cost and carbon emission analyses revealed that the above optimized formulation reduced both material cost and embodied carbon by approximately 12.5% and 22.3%. These findings provide a sustainable and cost-effective approach to improve the mechanical and hydraulic performance of cement–bentonite cut-off walls. Full article

The spatial variability of permeability coefficients in multi-component materials poses significant challenges for the seepage safety of high core rockfill dams. This study systematically investigates the influence mechanism of the spatial variability of permeability coefficients on seepage characteristics through a stochastic framework combining random field simulation, non-intrusive finite element analysis, and multi-scheme numerical experiments. Based on the measured data and statistical analysis, random fields of permeability coefficients are constructed, and eight computational schemes are designed to analyze the differential impacts of spatial variability in zones of the core wall, cut-off wall, rockfill, overburden, and curtain. The results show that the spatial variability of permeability coefficients in the rockfill, overburden, and curtain materials has a negligible effect on the seepage behavior, with the coefficient of variation of the hydraulic gradient at feature points remaining below 0.04. In contrast, the spatial variability of permeability in the core wall and cut-off walls significantly affects the seepage characteristics. Specifically, the hydraulic gradient in the core wall increases by an average of 4.8%, with a maximum increase of 34%, and the coefficient of variation of the hydraulic gradient at feature points ranges from 0.15 to 0.18. The maximum hydraulic gradient at the release point of the core wall rises from 1.67 to 1.75 when the spatial variability is considered. Additionally, the spatial variability of permeability in the core wall leads to greater discreteness in the hydraulic gradient of the cut-off walls, weakening the coordinated anti-seepage effect between the main and secondary cut-off walls. The statistical analysis reveals that the hydraulic gradient at feature points follows a normal distribution. Furthermore, when the coefficient of variation of the core wall permeability increases from 1.46 to 2.03, the maximum hydraulic gradient at key points rises from 2.0 to 2.3. These findings highlight the necessity for the strict quality control of permeability parameters in core wall and cut-off wall materials to ensure the long-term seepage safety of high core rockfill dams. Full article

Objective: To provide an overview of the technique and normal values of ultrasound studies of the bile system based on the published literature. Methods: A literature search for ultrasound studies with measurements of the bile ducts in healthy subjects was performed. Relevant data published between 1975 and end of 2024 were extracted, discussed, and complemented with the own experiences of the authors. The clinical implications are presented and discussed. Results: For the diameter of the common bile duct, reference values between 5 and 9 mm have been published. The main influencing factors are age and history of cholecystectomy, and other factors to be considered are discussed here. The cut-off for the common bile duct wall is set at 1.5 mm. The literature on measurements of intrahepatic bile ducts is scarce. A diameter of <2–3 mm can be considered normal. The method of ultrasound examination is presented here, as well as a comparison with other imaging methods and their clinical implications. Conclusions: Standardized measurement techniques and normal values in the context of influencing factors are crucial for the ultrasound examination of the bile system. Full article

Plastic Concrete is a low-strength ($f_{cm,28\mathrm{d}}$ ≤ 1.0 MPa), low-stiffness impervious concrete used for cut-off walls in earthen dams worldwide. These properties are achieved through a very high w/c ratio (w/c ≥ 3.0) and water-binding additions (e.g., bentonite). To date, the effect of mix design, especially w/c ratio, as well as bentonite content and type, on the long-term time development of the microstructural properties and corresponding compressive strength of Plastic Concrete has yet to be systematically studied. Furthermore, in the literature, mercury intrusion porosimetry (MIP) and X-ray diffractometry (XRD) have yet to be applied systematically to Plastic Concrete for this purpose. The present study closes this gap. Ten Plastic Concrete mixes with two bentonite–cement ratios, three types of sodium bentonite and two swelling times were produced. MIP and XRD measurements and compressive strength tests were performed at sample ages of 7 d, 28 d, 56 d, 91 d and four years. The results show that both MIP and XRD can be successfully used; however, meticulous sample preparation and data analysis must be considered. The porosimetry results show a bi-modal pore size distribution, with two age-dependent peaks at approximately 10,000–20,000 nm and 100–700 nm. The results also exhibit a clear pore refinement over time, with coarse porosity dropping from 26% to 15% over four years. In addition, the fine porosity peak is significantly refined over time and positively correlates with the significant increase in compressive strength. The XRD results show no unexpected crystalline phases over the same period. Overall, this study links MIP and corresponding compressive strength data specifically for Plastic Concrete for the first time, confirming the key role that the mix design of Plastic Concrete plays in defining its long-term microstructural and mechanical properties and ensuring more realistic cut-off wall design in the future. In addition, the experimental boundaries for MIP testing on Plastic Concrete are set out for the first time, enabling future research in this field. Full article

Background/Objectives: Vascular aging is associated with increased arterial stiffness and changes in the wall structure, leading to a loss of elasticity. Silicon is abundant in arteries and plays a key role in the synthesis and stabilization of elastin fibers. In animal models of accelerated cardiovascular aging, a specific nutritional supplement based on silicon-enriched spirulina (SpSi) has been shown to have beneficial effects on vascular function. The present study, designed as a randomized, double-blind, placebo-controlled trial, aimed to evaluate the effectiveness of this SpSi supplement on aging-related changes in vascular function among healthy older adults. Methods: Here, 120 healthy volunteers aged 60–75 years were enrolled and randomly assigned to either the SpSi group (n = 60) or placebo group (n = 60). Over 6 months, the participants received either 3.5 g of specific 1% silicon-enriched spirulina (SpSi group) or placebo tablets daily. The primary outcome was the assessment of arterial wall pressure waveforms, which included blood pressure (BP) readings and the determination of the aortic pulse wave velocity (aPWV). Secondary outcomes included the vasomotor endothelial function through post-ischemic vasorelaxation, measured using the reactive hyperemia index (RHI), and carotid intima–media thickness. Results: When considering the entire sample, none of the studied parameters differed between the placebo and SpSi groups. However, when focusing on individuals with high–normal blood pressure (i.e., systolic BP between 130 and 150 mmHg) and aPWV levels above cutoff values (>10 m/s), the BP decreased by 8% (p < 0.001) and aPWV decreased by 13.5% (p < 0.0001) in subjects receiving SpSi. In individuals with BP and aPWV levels below the cutoff values, no effect was observed. Conclusions: In healthy elderly individuals, SpSi supplementation improved high–normal blood pressure and aortic pulse wave velocity, suggesting an enhanced vascular function. Full article

Background: 1, 3-ß-D-Glucan (BDG) is an antigen present in the cell wall of many pathogenic fungi and is used as a marker for the early diagnosis of candidemia and discontinuation of empirical treatment. Changes in the epidemiology of Candida species might have a negative impact on the performance of serum BDG. The aim of this study was to analyze the performance of BDG in candidemia diagnosis focusing on species-specific differences in BDG sensitivity and BDG levels. Methods: The PRISMA system was used for the systematic search. The following databases were searched for articles published from January 2010 to November 2023: PubMed, Science Direct, and Scopus. Results: A total of 21 studies that met the inclusion criteria were included, reporting data from 1633 patients with candidemia; 11 reported both sensitivity and specificity, 15 reported species-specific sensitivity, and nine reported species-specific BDG levels. The pooled sensitivity of BDG in all studies was 0.73 (95% confidence interval (CI), 0.66-0.80), while the pooled sensitivity and specificity in 11 studies were 0.81 (95% CI 0.73-0.89) and 0.80 (95% CI 0.74-0.87). BDG pooled sensitivity (all assays) and BDG levels (for assays with cutoff of 80 pg/mL) were the highest in C. krusei (currently Pichia kudriavzevii) and the lowest in C. auris: 0.76 and 417 pg/mL for C. krusei, 0.73 and 345 pg/mL for C. albicans, 0.74 and 356 pg/mL for C. glabrata (currently Nakaseomyces glabrata), 0.70 and 324 pg/mL for C. tropicalis, 0.63 and 95 pg/mL for C. parapsilosis, 0.51 and 62 pg/mL for C. auris, and 0.44 and 79 pg/mL for other Candida species. These differences were statistically significant for BDG sensitivity and levels of C. albicans, C. glabrata, C. krusei, and C. tropicalis compared to C. auris, C. parapsilosis, and other Candida species. Conclusion: The sensitivity of BDG in candidemia diagnosis depends on the Candida species, with the lowest being for C. auris and C. parapsilosis. This might have a clinical impact in centers where these species are prevalent. Full article

Heavy metal-organic pollutants compound pollution at industrial legacy sites and have caused damage to the ecological environment and human health during recent decades. In view of the difficulty and high cost of post-contamination remediation, it is worth studying, and practically applying, cutoff walls to reduce the spread of pollution in advance. In this study, field-scale studies were carried out at e-waste dismantling legacy sites in Taizhou, Zhejiang Province of China, through the process of site investigation, numerical simulation, and cutoff wall practical application. Firstly, the concentrations and spatial distributions of Pb, Cd and polychlorinated biphenyls (PCBs) and poly brominated diphenyl ethers (PBDEs) were identified in both soil and groundwater. Then, potential dispersal routes of key combined contaminants (Pb and PCBs) at the soil–groundwater interface were systematically studied through numerical simulation applying Visual MODFLOW-MT3DMS. One site was chosen to predict the barrier effect of differently sized cutoff walls based on the migration path of compound pollutants. A protocol for a cutoff wall (50 m length × 2 m width × 3 m height) was finally verified and applied at the real contaminated site for the blocking of compound pollutant diffusion. Further, the groundwater quality of the contaminated site was monitored consecutively for six months to ensure the durability and stability of barrier measures. All pollutant indicators, including for Pb and PCB complex pollutants, were reduced to below the national Grade IV groundwater standard value, achieving environmental standards at these polluted sites and providing possibilities for land reuse. In summary, this field-scale test provided new ideas for designing cutoff walls to block the diffusion of complex pollutants; it also laid a basis for the practical application of cutoff walls in pollution prevention and control of complex contaminated sites and for soil–groundwater environmental protection at industrial heritage sites. Full article

Dam foundations are prone to leakage damage after being exposed to long-term water action, which seriously affects the operation safety of the dam. At present, concrete cut-off walls serve an important means of anti-seepage for dam foundations. However, due to construction challenges, the cut-off wall needs to be poured segment-by-segment during the construction process, and the joints between adjacent segments become weak parts for seepage prevention. Therefore, it is crucial to clarify the stress state of segmented discontinuous concrete cut-off walls. Based on the Lee-Fenves framework and the tension–compression constitutive relationship of fracture energy, a plastic damage calculation method was established in this paper to characterize the mechanical behavior of discontinuous cut-off walls. The method was then used to analyze the mechanical performance of discontinuous walls with segment joints containing slurry cake. The research results showed that compared to the continuous cut-off wall, the vertical settlement in the middle part of the discontinuous cut-off wall increased by 5.8%, and the displacement along the river flow direction decreased by 35.3%. As the wall segment width decreased, the joint opening and the degree of tensile damage were reduced accordingly, while the compressive damage in the middle and lower parts of the wall was intensified. As the wall depth decreased, the constraints and load on the bottom of the wall showed obvious changes, leading to a reduced stress and damage level of the wall. The findings provide reference for the design and safety control of cut-off walls. Full article

Composite geomembrane cut-off walls (CGCW) have been widely used for the remediation of polluted sites, especially where the environmental conditions are complex. Accurate predictions of the GMB hole leakage and CGCW performance are essential for engineering design and cost control. This paper establishes empirical equations to predict the leakages through the CGCWs based on the numerical models. Additionally, an analytical solution for contaminant migration through the CGCW is proposed considering the effects of GMB holes. The accuracy of the established equations and analytical solution is verified by the numerical models. The key effects of the GMB thickness (T_G), head loss (H_G), cut-off wall hydraulic conductivity (k_G), hole radius (r_G) and shape on the leakage and CGCW performance are investigated. The results show that compared with other hole shapes, the leakage through the circular hole is lowest. This is mainly because the shape factor for the circular hole is 1.15–1.3 times lower than that for other shapes of holes with the same area. Additionally, the effects of the hole geometric properties and head loss on the CGCW performance can be more significant when the cut-off wall hydraulic coefficient is small. For example, the breakthrough time differences between the cases with r_G = 0.005 m and 0.05 m are 0.8 and 5.0 years when k_G = 10⁻¹⁰ and 10⁻⁹ m/s, respectively. This is because the impermeability of the CGCW is good when k_G is small. This will weaken the impacts of the hole geometric properties on the leakage. The proposed empirical equations and analytical solution can provide effective suggestions for the design of the CGCW in different GMB hole cases. Full article

Background: Accumulating evidence from clinical trials, large registries, and meta-analyses of population studies shows that increased Blood Pressure Variability (BPV) is predictive of Cardiovascular (CV) outcomes, independently of the average Blood Pressure (BP) values. One of the mechanisms explaining the relationship between BPV and target organ damage is the inflammatory response. The Systemic Immune Inflammation Index (SII), which relies on peripheral blood cell counts, including platelets, neutrophils, and lymphocytes, has emerged as a predictor of prognosis and outcomes in various diseases. The aim of this study was to investigate the association of the SII with Ambulatory Blood Pressure Variability (ABPV) in newly diagnosed hypertensive patients. Methods: This study was designed as a cross-sectional observational study. A total of 1606 consecutive newly diagnosed Hypertension (HT) patients were included in the study. The population was evaluated across 3 different categories according to HT grades (5 groups), eligibility for antihypertensive therapy (2 groups) and ABPV levels (2 groups). Results: Significant differences were observed between ABPV groups in terms of Neutrophil to Lymphocyte ratio, Platelet to Lymphocyte ratio, glucose, SII, high-sensitive CRP, HT grade, Inter-Ventricular Septum, Posterior Wall thickness, and Left Ventricular Mass (p < 0.005). There was a significant relationship between SII and ABPV (r: 0.619, p < 0.05). At the cutoff value of 580.49, SII had 77% sensitivity and 71% specificity for ABPV > 14 (AUC: 0.788). Conclusions: SII may assist in developing an early treatment approach to minimize complications in patients with high ABPV who are at a higher risk of CV events. Full article