Search Results (954)

Prostate cancer remains one of the most prevalent malignancies among men, and emerging evidence proposed a potential role for periprostatic adipose tissue (PPAT) in tumor progression. However, its relationship with imaging-based risk stratification systems such as PI-RADS remains uncertain. This retrospective observational study aimed to evaluate whether periprostatic and subcutaneous fat thickness are associated with PI-RADS scores or PSA levels in biopsy-naïve patients. We retrospectively reviewed 104 prostate MRI scans performed between January 2020 and January 2024. Fat thickness was measured on axial T2-weighted images, and statistical analyses were conducted using Spearman’s correlation and multiple linear regression. In addition to linear measurements, we also assessed periprostatic fat volume and posterior fat thickness derived from imaging data. No significant correlations were observed between fat thickness (either periprostatic or subcutaneous) and PI-RADS score or PSA values. Similarly, periprostatic fat volume showed only a weak, non-significant correlation with PI-RADS, while posterior fat thickness demonstrated a weak but statistically significant positive association. Additionally, subgroup comparisons between low-risk (PI-RADS < 4) and high-risk (PI-RADS ≥ 4) patients showed no meaningful differences in fat measurements. These findings suggest that simple linear fat thickness measurements may not enhance imaging-based risk assessment in prostate cancer, though regional and volumetric assessments could offer modest added value. Full article

Objectives: Nasal reconstructive surgery following skin cancer resection is challenging, with esthetic concerns impacting patients’ quality of life. Non-surgical rhinoplasty may be an alternative to repeated surgeries. This study aimed to evaluate non-surgical rhinoplasty esthetic benefits and subjective patient outcomes after skin cancer resection. Methods: We conducted a retrospective study on patients with post-operative esthetic dissatisfaction after nasal skin cancer surgery, who underwent non-surgical rhinoplasty with hyaluronic acid. Subjective benefits were evaluated with the FACE-Q Rhinoplasty self-questionnaire at three consultations: before injection (baseline), and at one and two months after. Two-dimensional and three-dimensional Vectra H2 photographs were used to assess subjective esthetic concerns and objective volumetric changes. Results: The study included six female patients with an average age of 58.3 years. They had undergone, on average, five nasal surgeries for cancer. The mean FACE-Q scores were 53.3 (±10.31), 77.5 (±4.18), and 79.7 (±6.76), respectively, at baseline, one month, and two months. Significant differences were observed between baseline and one month (p < 0.001) and between baseline and two months (p < 0.001), but not between one and two months. The was a mean volumetric gain of 1.13 mL at one month and 1.19 mL at two months. Conclusions: This preliminary study suggested that hyaluronic acid-based non-surgical rhinoplasty could improve esthetic outcomes and quality of life in patients who had undergone nasal skin cancer surgery. These findings highlight a potential role for this minimally invasive technique in selected post-reconstructive cases, although the small sample size limited the generalizability of the results and underlined the need for further prospective evaluation. Full article

Modern aircraft increasingly utilizes highly integrated electronic equipment, driving continuously increasing heat dissipation demands. Vapor compression refrigeration systems demonstrate stronger alignment with future aircraft thermal management trends, leveraging their superior volumetric cooling capacity, high energy efficiency, and independence from engine bleed air. This paper reviews global research progress on aircraft vapor compression refrigeration systems, covering performance optimization, dynamic characteristics, control strategies, fault detection, and international development histories and typical applications. Analysis identifies emerging challenges under large-temperature-range cooling requirements, with comparative assessment establishing zeotropic mixture auto-cascade vapor compression refrigeration systems as the optimal forward-looking solution. Finally, recognizing current research gaps, we propose future research directions for onboard auto-cascade vapor compression refrigeration systems: optimizing refrigerant mixtures for flight conditions, achieving efficient gas-liquid separation during variable overloads and attitude conditions, and developing model predictive control with intelligent optimization to ensure reliability. Full article

Background: Vascular risk factors (VRFs) are known to influence cerebral small vessel disease (cSVD) burden and progression. However, their specific impact on the presence and distribution of each cSVD imaging marker (white matter hyperintensity [WMH], perivascular spaces [PVSs], lacunes, and cerebral microbleeds [CMBs]) and their spatial distribution remains unclear. Methods: We conducted a retrospective analysis of 93 patients with lacunar stroke with a standardized investigational magnetic resonance imaging protocol using a 3T scanner. WMH and PVSs were segmented semi-automatically, and lacunes and CMBs were manually segmented. We assessed the univariable associations of four common VRFs (hypertension, hyperlipidemia, diabetes, and smoking) with the load of each cSVD marker. Then, we assessed the independent associations of these VRFs in multivariable regression models adjusted for age and sex. Spatial lesion patterns were explored with regional volumetric comparisons using Pearson’s coefficient analysis, which was adjusted for multiple comparisons, and by visually examining heatmap lesion distributions. Results: Hypertension was the VRF that exhibited stronger associations with the cSVD markers in the univariable analysis. In the multivariable analysis, only lacunes (p = 0.009) and PVSs in the basal ganglia (p = 0.014) and white matter (p = 0.016) were still associated with hypertension. In the regional analysis, hypertension showed a higher WMH load in deep structures and white matter, particularly in the posterior periventricular regions. In patients with hyperlipidemia, WMH was preferentially found in hippocampal regions. Conclusions: Hypertension was confirmed to be the VRF with the most impact on cSVD load, especially for lacunes and PVSs, while the lesion topography was variable for each VRF. These findings shed light on the complexity of cSVD expression in relation to factors detrimental to vascular health. Full article

Everolimus (EVE), an mTOR inhibitor, is widely used in solid organ transplantation (SOT) because of its immunosuppressive properties. Due to its narrow therapeutic window and significant pharmacokinetic variability, therapeutic drug monitoring (TDM) is essential for achieving optimal outcomes. We developed and thoroughly validated a robust LC-MS/MS method to measure EVE levels in venous whole blood (WB) and capillary blood collected using two microsampling devices: Mitra™ (volumetric absorptive microsampling, VAMS) and Capitainer^® (quantitative dried blood spot, qDBS). The validation followed EMA and IATDMCT guidelines, assessing linearity (1.27–64.80 ng/mL for WB and 0.50–60 ng/mL for VAMS/qDBS), as well as selectivity, accuracy, precision, matrix effects, recovery, stability, and incurred sample reanalysis. Clinical validation involved 66 matched samples from 33 adult SOT recipients. The method demonstrated high accuracy and precision across all matrices, with no significant carryover or matrix interference. Statistical analysis using Passing–Bablok regression and Bland–Altman plots showed excellent agreement between the microsampling methods and the venous reference. Hematocrit effects were tested both in laboratory conditions and on clinical samples and were found to be negligible. This study provides the first comprehensive analytical and clinical validation of the Mitra and Capitainer devices for EVE monitoring. The validated LC-MS/MS microsampling method supports decentralized, patient-centred TDM, offering a reliable alternative to conventional blood sampling in transplant care. Full article

Semi-natural grasslands are some of the most species-rich habitats in Europe and provide important ecosystem services such as biodiversity conservation, carbon sequestration and soil fertility maintenance. This study investigates how different intensities of grassland management affect the composition of functional groups and soil chemical properties. Five grassland management systems were analyzed: Cut3—three cuts per year; LGI—low grazing intensity; CG—combined cutting and grazing; Cut4—four cuts per year; and HGI—high grazing intensity. The functional groups assessed were grasses, legumes and forbs, while soil samples from three depths (0–10, 10–20 and 20–30 cm) were analyzed for their chemical properties (soil organic carbon—SOC; soil total nitrogen—STN; inorganic soil carbon—SIC; soil organic matter—SOM; potassium oxide—K₂O; phosphorus pentoxide—P₂O₅; C/N ratio; and pH) and physical properties (volumetric soil water content—VWC; bulk density—BD; and porosity—POR). The results showed that less intensive systems had a higher proportion of legumes, while species diversity, as measured via the Shannon index, was the highest in the Cut4 system. The CG system tended to have the highest SOC and STN at a 0–10 cm depth, with a similar trend observed for SOC_stock at a 0–30 cm depth. The Cut4, HGI and CG systems also had an increased STN_stock. Both grazing systems had the highest P₂O₅ content. A tendency towards a higher BD was observed in the top 10 cm of soil in the more intensive systems. Choosing a management strategy that is tailored to local climate and site conditions is crucial for maintaining grassland stability, enhancing carbon sequestration and promoting long-term sustainability in the context of climate change. Full article

Material wear significantly impacts the clinical success and longevity of dental ceramic restorations. This in vivo study aimed to assess the wear behavior of IPS Empress^® glass-ceramic inlays and onlays over 14 years, considering the influence of different antagonist materials. Fifty-four indirect restorations of 21 patients were available for comprehensive wear analysis, with complete follow-up data for up to 14 years. Three-dimensional measurements relied on digitized epoxy resin models produced immediately post-insertion (baseline) and subsequently at 2, 4, and 14 years. The occlusal region on the baseline model was delineated for comparative analysis. Three-dimensional superimpositions with models from subsequent time points were executed to assess wear in terms of average linear wear and volumetric loss. Statistical analyses were conducted in R (version 4.4.1), employing Mann–Whitney U tests (material comparisons) and Wilcoxon signed rank tests (time point comparisons), with a significance threshold of p ≤ 0.05. During the entire study period, an increase in wear was observed at each assessment interval, gradually stabilizing over time. Significant differences in substance loss were found between the follow-up time points, both for mean (−0.536 ± 0.249 mm after 14a) and integrated distance (−18,935 ± 11,711 mm³ after 14a). In addition, significantly higher wear was observed after 14 years with gold as antagonist compared to other materials (p ≤ 0.03). The wear behavior of IPS Empress^® ceramics demonstrates clinically acceptable long-term outcomes, with abrasion characteristics exhibiting stabilization over time. Full article

Background and Objectives: Adequate bone quality is essential for promoting initial bone ingrowth and preventing early migration during cementless total knee arthroplasty (TKA). However, gold-standard criteria for identifying suitable bone strength have yet to be established. Dual-energy computed tomography (DECT)-based volumetric bone mineral density (vBMD) is an emerging tool for assessing bone quality. This study aimed to determine whether DECT-derived vBMD can accurately predict suitable bone strength for cementless TKA. Materials and Methods: A total of 190 patients undergoing primary TKA with a standardized posterior-stabilized implant were prospectively enrolled. Prior to TKA, DECT-derived vBMD was measured in the femoral box region. Actual bone strength was evaluated using an indentation test on resected femoral box specimens. Correlation and linear regression analyses were performed to assess the relationship between DECT vBMD and actual bone strength. Receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) calculations were used to determine the optimal cut-off value and diagnostic accuracy of DECT vBMD in identifying candidates suitable for cementless TKA. Results: DECT-derived vBMD exhibited a strong correlation with actual bone strength (correlation coefficient = 0.719, p < 0.01), while linear regression analysis revealed a moderate association (R² = 0.51, p < 0.01). In addition, it demonstrated excellent diagnostic performance in predicting adequate bone quality for cementless TKA, yielding an AUC of 0.984, with a sensitivity of 91.9% and a specificity of 92.0%. Conclusions: DECT-derived vBMD is a reliable and accurate tool for assessing bone strength around the knee and predicting the suitable bone quality for cementless TKA. Full article

Objectives: To employ artificial intelligence (AI) to automatically measure bone mineral density (BMD) and intramuscular fat in computed tomography (CT) images of patients with fractures and explore the association between these parameters and fracture healing. Methods: This retrospective study included patients who underwent baseline CT scans for rib fracture diagnosis and follow-up CT scans for fracture healing assessment at our hospital between 2012 and 2023. The volumetric BMD of the entire first lumbar vertebra (L1) and the paraspinal intramuscular fat area (PIFA) at the midsection of L1 in the baseline CT were extracted using AI. The primary outcomes, including callus formation, volume increase, and poor healing, and logistic regression were used to analyze the relationships between BMD and PIFA with primary outcomes. Results: Overall, 297 fractures from 53 patients (24 males; mean age: 53.83 ± 10.86 years) were included in this study. In multivariate regression analysis, a 1 standard deviation (SD) decrease in BMD was identified as an independent prognostic factor for reduced callus formation (odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.50–0.97), diminished volume increase (OR = 0.70, 95% CI = 0.51–0.96), and elevated poor fracture healing at follow-up (OR = 2.08, 95% CI = 1.38–3.13). Similarly, a 1 SD increase in PIFA was an independent prognostic factor for reduced callus formation (OR = 0.24, 95% CI = 0.16–0.37), diminished volume increase (OR = 0.33, 95% CI = 0.23–0.49), and elevated poor fracture healing at follow-up (OR = 2.09, 95% CI = 1.50–2.93). Therefore, a model combining BMD, PIFA, and clinical characteristics significantly outperformed a model that included only clinical characteristics in predicting callus formation, volume increase, and poor fracture healing, with areas under the curve of 0.790, 0.749, and 0.701, respectively (all p < 0.001). Conclusions: BMD and PIFA can be used as early predictors of fracture healing outcomes and can help clinicians select appropriate interventions to prevent poor healing. Full article

Background: Assessment of the peritoneal cancer burden is crucial for determining the optimal treatment in advanced ovarian cancer (AOC). Effective non-invasive methods to predict tumour load remain limited. This study aimed to assess the applicability of 2-[¹⁸F]FDG PET/CT volumetric parameters, metabolic tumour volume (MTV), and total lesion glycolysis (TLG) for predicting the surgical peritoneal cancer index (PCI) in AOC before primary treatment. Methods: Patients with high-grade serous or undifferentiated AOC who underwent surgical PCI evaluation and 2-[¹⁸F]FDG PET/CT between 01/2013 and 12/2018 were included. MTV and TLG were calculated using thresholds of 40% and 50% (MTV40, MTV50, TLG40, and TLG50). Correlations between the peritoneal carcinomatosis MTV (car_MTV) and TLG (car_TLG) were analysed. The capacity of volumetric parameters to estimate PCIs above or below 14 and 20 was assessed for the whole abdominal cavity and in per-quadrant analysis, specifically for upper-abdomen areas 1, 2, and 3 (MTV40_1, 2, 3 and TLG40_1, 2, 3). Results: MTV40, MTV50, TLG40, and TLG50 significantly correlated with the PCI in the final study population (n = 45). MTV40 showed a Pearson coefficient of 0.41 (p = 0.003). MTV3_40 (AUC 0.79) and TLG3_40 (AUC 0.81) presented the highest AUCs for predicting a PCI above or below 14. The volumetric parameters allowed the prediction of a PCI greater or less than 20, with an AUC of 0.77 for MTV40_1 and 0.78 for TLG40_1. Conclusions: 2-[¹⁸F]FDG PET/CT MTV and TLG correlate significantly with the surgical PCI when assessing peritoneal carcinomatosis or quadrant-specific disease. This approach offers a reliable non-invasive method for evaluating tumour burden in AOC. Full article

This study assessed the applicability of visible–near-infrared (vis-NIR) spectroscopy to predicting the water retention characteristics of forest soils in Japan, which vary widely owing to the presence of volcanic ash. Soil samples were collected from 34 sites, and the volumetric water content was measured at eight levels of matric suction. Spectral data were processed by using the second derivative of the absorbance, and regression models were developed by using explainable boosting machine (EBM), which is an interpretable machine learning method. Although the prediction accuracy was limited owing to the small sample size and soil heterogeneity, EBM performed better under saturated conditions (R² = 0.30), which suggests that vis-NIR spectroscopy can capture water-related features, especially under wet conditions. Importance analysis consistently selected wavelengths that were associated with organic matter and hydrated clay minerals. The important wavelengths clearly shifted from free-water bands in wet soils to mineral-related absorption bands in dry soils. These findings highlight the potential of coupling vis-NIR spectroscopy with interpretable models like EBM for estimating the hydraulic properties of forest soils. Improved accuracy is expected with larger datasets and stratified models by soil type, which can facilitate more efficient soil monitoring in forests. Full article

This study explores the optimisation of nozzle design for external twin fluid, single-stage atomisation in handling high-viscosity, shear-thinning polydimethylsiloxane (PDMS). A single PDMS grade was employed and atomised using unheated sonic air and the viscosity was varied by the fluid temperature. A systematic experimental approach was used, varying nozzle geometry—specifically apex angle, gas nozzle diameter, and number of gas nozzles—to identify the optimal nozzle configuration (ONC). The spray qualities of the nozzle configurations were evaluated via high-speed imaging at 75,000 FPS. Shadowgraphy was employed for the optical characterisation of the spray, determining the optimal volumetric air-to-liquid ratio (ALR), a key parameter influencing energy efficiency and operational cost, and for assessing droplet size distributions under varying ALR and viscosity of PDMS. The ONC yielded a Sauter mean diameter $d_{32}$ of 570 × 10⁻⁶$\mathrm{m}$, at an ALR of 8532 and a zero-shear viscosity of 15.9 $\mathrm{Pa}$ $\mathrm{s}$. The results are relevant for researchers and engineers developing twin fluid atomisation systems for challenging industrial fluids with similar physical properties, such as those in wastewater treatment and coal–water slurry atomisation (CWS). This study provides design guidelines for external twin fluid atomisers to enhance atomisation efficiency under such conditions. Full article

This study examines the mechanical and physical performance of lightweight concretes incorporating acidic pumice aggregate, with a particular focus on their behavior under thermal exposure. Pumice sourced from the Bitlis-Tatvan region was used as a partial replacement for limestone aggregate at volumetric substitution levels of 50%, 60%, and 70% (designated LC50, LC60, and LC70, respectively), alongside a conventional control mix (NC). Experimental investigations included flexural and compressive strength tests, capillary water absorption measurements, and mass loss assessments at elevated temperatures (100 °C, 200 °C, and 300 °C). The results indicate that increasing pumice content leads to a significant reduction in mechanical strength, as evidenced by a strong negative correlation (e.g., −0.994 for compressive strength), and results in increased water absorption due to the higher porosity of pumice. Thermal exposure caused more pronounced weight loss in pumice-rich mixtures, primarily attributable to moisture evaporation and the formation of surface voids, particularly in LC60 and LC70 specimens. Although the incorporation of pumice effectively reduces the unit weight of concrete, it compromises both strength and durability, highlighting a critical trade-off between weight reduction and structural performance. Future studies are recommended to quantitatively assess the relationship between compressive and flexural strengths to address current limitations. Additionally, advanced microstructural analyses (e.g., SEM, XRD), fire resistance evaluations at higher temperatures, and the development of hybrid mixes incorporating supplementary cementitious materials (SCMs) should be further explored. Full article

Background: Artificial tooth wear impacts prosthesis durability and function; understanding material–antagonist interactions guides clinical choices. Aim: This in-vitro study aimed to assess the wear behavior of isosit and nanohybrid composite resin artificial teeth when opposed to various antagonist materials using 3D volumetric wear analysis. Materials and Methods: Sixty specimens (n = 10 per group) were prepared from two artificial tooth materials and assigned to six antagonist combinations: isosit–isosit, isosit–nanohybrid composite, isosit–porcelain, nanohybrid composite–isosit, nanohybrid composite–nanohybrid composite, and nanohybrid composite–porcelain. Specimens were scanned before and after 600,000 chewing cycles using a structured-light 3D scanner. Volumetric wear was calculated by superimposing pre- and post-test scans. Data were analyzed using two-way ANOVA and Tukey’s HSD test (α = 0.05). Results: Porcelain antagonists produced the highest wear values (p < 0.05). No significant difference was found between isosit and nanohybrid antagonists (p > 0.05). Identical material pairings showed less wear, though differences were not statistically significant. Conclusions: Porcelain as an antagonist increased wear risk. Using identical materials bilaterally, such as isosit–isosit or nanohybrid–nanohybrid, may help reduce artificial tooth wear in removable prostheses. Full article

Variable-speed reciprocating compressors (VSRCs) have been increasingly used in domestic refrigeration due to their ability to modulate cooling capacity and reduce energy consumption. A detailed understanding of performance-limiting factors such as volumetric and exergetic inefficiencies is essential for optimizing their operation. An experimentally validated simulation model was developed using GT-SUITE to analyze a VSRC operating with R-600a across speeds from 1800 to 6300 rpm. Volumetric inefficiencies were quantified using a stratification methodology, while an exergy-based approach was adopted to assess the main sources of thermodynamic inefficiency in the compressor. Unlike traditional energy analysis, exergy analysis reveals where and why irreversibilities occur, linking them directly to power consumption and providing a framework for optimizing design. Results reveal that neither volumetric nor exergy efficiency varies monotonically with compressor speed. At low speeds, exergetic losses are dominated by the electrical motor (up to 19% of input power) and heat transfer (up to 13.5%). Conversely, at high speeds, irreversibilities from fluid dynamics become critical, with losses from discharge valve throttling reaching 5.8% and bearing friction increasing to 6.5%. Additionally, key volumetric inefficiencies arise from piston–cylinder leakage, which causes up to a 4.5% loss at low speeds, and discharge valve backflow, causing over a 5% loss at certain resonant speeds. The results reveal complex speed-dependent interactions between dynamic and thermodynamic loss mechanisms in VSRCs. The integrated modeling approach offers a robust framework for diagnosing inefficiencies and supports the development of more energy-efficient compressor designs. Full article