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Space-Frequency Based Computed Tomography Texture Analysis is more Robust than Image Domain Features for Radiomics and AI Applications
No full textPurposeAI and radiomics-based analyses tend to improve global health equity. Thus, reliability is a key factor in the sustainability of their services. Computed Tomography Texture Analysis (CTTA) provides effective results in diagnosis, treatment, and follow-up for various clinical conditions. Unfortunately, it is also shown that CTTA has low repeatability, and reproducibility, and is highly dependent on modality, acquisition, and reconstruction parameters.For instance, The Credence Cartridge Radiomics (CCR) phantom is a specially designed tool used to evaluate the robustness and variability of radiomics features in computed...Read moreMethods and materialsThe phantoms and feature extraction pipeline is illustrated in [Fig 1].Five different texture phantoms, which were 3D-printed using the Raise3D Pro3 Plus 3D printer are analyzed.[Fig 2] The printing material was PLA for all phantoms, each of which had a 4 cm × 4 cm cross-sectional area. Three phantoms were designed as line phantoms, referred to as vertical, horizontal, and diagonal phantoms. One phantom was square-shaped, and the fifth phantom was star-shaped having eight solid slices. A sixth phantom is also designed to have a...ResultsIn most of the violin plots, data distributions of the GLCM side propagate widely in terms of spatial domain analysis, whereas the DTCWT side has a more concentrated area for spatial-frequency domain analysis. For diagonal, horizontal, and square textures in the violin plots, the 1st, 2nd, and 3rd quartiles are separable, while honeycomb, sinusoidal, and star textures have close quartiles. In our experimental results, the median value of each DTCWT-based feature type across all textures is close to 1 (as the normalized value) in most...ConclusionThe repeatability, and reproducibility of SFBT CTTA are more robust to CT acquisition parameters and variations in data characteristics compared to image domain (i.e. GLCM) texture features. The SFBT and image domain texture features may have similar robustness only when the texture is rotation invariant or symmetric with respect to its origin. Since textures in real medical images mostly do not have such symmetry and rotation invariance properties, SFBT CTTA features should be preferred for radiomics analyses.</div
Red mud incorporated clay roof tiles as visible light‐active photocatalysts for building applications
No full textThe effects of COVID-19 on the input usage and revenue generation performance of the EU fishery sector
No full textThis study investigates the impact of the COVID-19 pandemic on the EU fishery sector across EU countries, with a particular emphasis on input utilization and its implications for revenue generation, using data sourced from the Scientific, Technical, and Economic Committee for Fisheries (STECF). It explores how changes in input utilization have influenced the sector's overall efficiency by non-radial DEA model with the Russell measure. Energy efficiency, vessel capacity efficiency, crew efficiency, operational cost efficiency, and technical efficiency in the EU fishery sector are measured as 0.583, 0.632, 0.487, 0.788, and 0.599, respectively. The study finds that the COVID-19 pandemic has led to changes in both input usage efficiency and revenue generation efficiency in EU countries compared to the pre-pandemic period. Input usage efficiency decreased from 0.5939 to 0.5383, while revenue generation efficiency was 1.367 in the pre-COVID-19 period and 1.822 during the COVID-19 period. Despite using 48 % more inputs during the COVID-19 period, due to the pandemic the sector suffered a loss of potential revenue that could have been %45.5 times higher. During the COVID-19 pandemic, there was a decrease in energy efficiency in the fisheries sector, while crew and operational cost efficiencies increased. Nevertheless, COVID-19 did not significantly affect fishery days and vessel capacity efficiencies. This suggests that the EU fisheries sector, during the pandemic, maintained its pre-pandemic fisheries revenue with higher energy consumption but achieved the same revenue level with fewer crew members and reduced operational costs. During the COVID-19 period, Denmark, France, and Slovenia kept their income generation performance steady. Bulgaria, however, saw the biggest drop in income generation during the pandemic
Microglia-like cells from patient monocytes demonstrate increased phagocytic activity in probable Alzheimer's disease
No full textAlzheimer's disease (AD) is a neurodegenerative disorder that is characterized by the accumulation of amyloid plaques, phosphorylated tau tangles and microglia toxicity, resulting in neuronal death and cognitive decline. Since microglia are recognized as one of the key players in the disease, it is crucial to understand how microglia operate in disease conditions and incorporate them into models. The studies on human microglia functions are thought to reflect the post-symptomatic stage of the disease. Recently developed methods involve induced microglia-like cells (iMGs) generated from patients' blood monocytes or induced pluripotent stem cells (iPSCs) as an alternative to studying the microglia cells in vitro. In this research, we aimed to investigate the phenotype and inflammatory responses of iMGs from AD patients. Monocytes derived from blood using density gradient centrifugation were differentiated into iMGs using a cytokine cocktail, including granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-34 (IL-34). After differentiation, cells were assessed by morphological analysis and a microglia surface marker, TMEM119. We used stimulants, lipopolysaccharide (LPS) and beta-amyloid, to examine iMGs' functions. Results showed that iMGs derived from AD patients exhibited increased secretion of pro-inflammatory cytokines upon LPS stimulation. Furthermore, their phagocytic ability was also heightened in stimulated and unstimulated conditions, with cells derived from patients showing increased phagocytic activity compared to healthy controls. Overall, these findings suggest that iMGs derived from patients using the direct conversion method possess characteristics of human microglia, making them an easy and promising model for studying microglia function in AD
Investigating The Influence of Micro-Spoiler Placement on The Aerodynamic Characteristics and Vibration Behavior of NACA0021 Airfoil
No full textThis study investigates the aerodynamic performance and vibration characteristics of NACA0021 airfoil under different angles of attack. Respectively, the following angles were analyzed: 0°, 5°, 10°, 15°, 20°, 25°, 30°, 40°, 50°, 60°. Three different airfoils, which are a baseline airfoil, an airfoil with a mid-chord micro spoiler, and an airfoil with quarter-chord micro spoiler were analyzed under Reynolds number of 1E6. Lift and drag coefficients were calculated for each airfoil under each of those specified angles of attack to assess the aerodynamic performance of the airfoils. A mesh independence analysis was employed to ensure the accuracy of the airfoils' aerodynamic performance.The results show that the baseline airfoil experiences stall at an angle of attack of around 15°, while airfoils with micro spoilers reach the stall at an angle of attack of around 20°. Featuring a micro spoiler on airfoils enhance aerodynamic performance by delaying stall through a reduction of flow separation. To obtain the structural response of airfoils, two-way FSI simulations were performed using the intrinsic FSI solver available in ANSYS FLUENT. This solver allows for the coupling of the fluid and structural domains. Airfoils’ tip displacement measurements from the simulations were demonstrated, and the effectiveness of micro spoilers was explored.</p
Investigating the Role of Symptom Duration and Critical Shoulder Angle in Predicting Acromiohumeral Interval Reversibility in Patients With Massive Rotator Cuff Tears
No full textBackground: Acromiohumeral interval (AHI) reversibility is used to evaluate whether superior humeral migration is fixed or flexible in patients with massive rotator cuff tears (MRCTs). AHI reversibility is measured as the difference in the AHI observed between standard and stress radiography. However, factors affecting AHI reversibility have not been studied in the existing literature. Purpose: To investigate potential factors affecting AHI reversibility in patients with MRCTs. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective analysis was conducted on 58 patients with MRCTs, who had undergone magnetic resonance imaging, computed tomography, and stress radiography of the same shoulder. Potential factors affecting AHI reversibility were evaluated by stepwise regression analysis. Results: A total of 58 patients (26 male, 32 female) were included in this study. The mean age of the patients was 66.4 ± 8.3 years. There were 33 patients classified as having a reversible AHI and 25 patients classified as having an irreversible AHI. Age, time from symptom onset, anteroposterior tear size, critical shoulder angle (CSA), acromial index, and subscapularis Goutallier grade were associated with AHI reversibility in univariate analysis. Multivariate linear regression analysis showed that a longer time from symptom onset and a bigger CSA were significantly associated with lower AHI reversibility. No significant association was found between AHI reversibility and sex; body mass index; activity level; tear retraction; biceps condition; deltoid cross-sectional area; and Goutallier grade of the supraspinatus, infraspinatus, and teres minor muscles. The cutoff values to predict AHI reversibility for time from symptom onset and CSA were found to be 5.5 years and 38°, respectively. Conclusion: Time from symptom onset (>5.5 years) and CSA (>38°) were significant independent factors of AHI reversibility. These factors should be considered for the decision-making process in patients with MRCTs
ZnO/PMMA Nanofibers for the Photocatalytic Water Remediation
No full textIn this study, a novel ZnO/PMMA nanofiber catalyst was fabricated using electrospinning, resulting in a barbed wire-like structure that enhances photocatalytic performance. The research aimed to investigate the material's effectiveness in degrading organic pollutants under UV light, providing a sustainable solution for water purification. Comprehensive characterization techniques, including XRD, XPS, SEM, EDS, and FTIR, were employed to analyze the crystal structure, micromorphology, and elemental composition of the catalyst. Photocatalytic degradation experiments showed that up to 91% degradation was achieved after 60 min of UV light irradiation at pH 11, with no significant bulk adsorption observed, confirming the dominance of the photocatalytic mechanism. The optimized pH of 11 was found to be ideal for achieving high degradation rates. This novel ZnO/PMMA nanofiber structure demonstrates significant potential for environmental applications, particularly in water purification, offering an efficient and sustainable approach to pollutant removal
Phytochemical Profiles, Antimicrobial and Antioxidant Activity of <i>Knautia integrifolia</i> (L.) Bertol. subsp. <i>integrifolia</i>
No full textThe genus Knautia (L.) (Caprifoliaceae) is widely distributed in the Mediterranean region and is represented by 11 species of flora in Turkey. This study conducted a detailed phytochemical investigation of the methanol extract of the whole plant of K. integrifolia using a combination of LC-ESI-FT-MS and NMR analyses. According to the results of this analysis, 25 compounds were identified in the methanol extract of K. integrifolia. The extract is particularly rich in phenolic secondary metabolites, including phenolic acid derivatives, flavonoid glycosides, and flavones, along with the presence of triterpenoid compounds. Additionally, the total phenolic content of the K. integrifolia methanol extract was evaluated. Considering the pharmacological activities reported for Knautia species, the antioxidant potential of the methanol extract was assessed using the DPPH radical scavenging assay, resulting in a value of 77.5% when compared to the ascorbic acid standard. In this study, antimicrobial activity tests were performed on K. integrifolia methanol extract for the first time. The results indicated that the extract demonstrated greater susceptibility to Staphylococcus epidermidis compared to the control group. At the same time, Pseudomonas aeruginosa exhibited a minimum inhibitory concentration value, indicating high sensitivity to the methanol extract
The effect of a single dose of Mk-801 use on adult brain tissue after an experimental head trauma model applied in immature rats
No full textObjective: Within the scope of this research, the long-term effects of experimental blunt head trauma on immature rats and MK-801 administered acutely after trauma on the brain tissue will be examined. In addition, the impact of trauma and MK-801 on Nestin and CD133, which are essential stem cells, will be evaluated by immunohistochemical and ELISA methods. Methods: In this study, the contusion trauma model was used. Sprague Dawley rats 30 7-day-old were divided into three groups: Group 1 (n = 10) control group, Group 2 (n = 10) trauma Group (head trauma applied), and Group 3 (n = 10) MK-801 + trauma Group. In the third group, immediately after head trauma, MK-801 (Sigma M107) dissolved in physiological saline was administered as a single dose of 1 mg/kg ip. Results: The concentration of nestin was significantly higher in the control group compared to both the trauma and trauma+drug groups (p < 0.001). CD133 was statistically significantly higher in the control group compared to the other two groups (p = 0.002). It was determined that the differences in Nestin CA1 and DG measurements resulted from the trauma and control and trauma and trauma+drug groups, and the differences in CD133 CA1 and DG measurements resulted from the trauma and control group. Conclusion: The positive effect of MK-801 on neuroprotective and neuronal proliferation was elaborated. Administration of MK-801 significantly induced nestin and CD133 concentrations in the injured tissue