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Multi-class cancer diagnosis on histopathological images with deep ensemble learning model
No full textCancer is one of the leading causes of death worldwide. As the cause of one in six deaths, cancer causes a financial and emotional burden on individuals and a socio-economic burden on societies. Early detection of cancer significantly increases the chances of survival. In this study, we propose a computer-aided cancer diagnosis method that detects cancer on histopathologic images using current image processing and deep learning techniques and is intended to help diagnostic decision making. A stacking-based ensemble learning model using transfer learning is developed for the proposed cancer diagnosis method. In the proposed model, DenseNet 201 and EfficientNet B7 are used as base learners, and a two-layer CNN architecture is used as a meta-learner. The proposed model is trained and tested on a large dataset using lung, colon, oral and breast cancer data. When the results of the experimental studies are analyzed, the proposed model achieved 99 % accuracy on lung cancer data, 100 % accuracy on colon cancer data, 100 % accuracy on lung and colon cancer data, 85 % accuracy on breast cancer data, 86 % accuracy on oral cancer data and 90 % accuracy on a dataset containing four different cancer types with nine classes. Considering these results, the performance of the proposed model was found to be satisfactorily high. Thus, it is concluded that the proposed model can be used in computer-aided decision-making systems to assist medical professionals
Lifespan trajectory of claustrum volume in humans – effect of age, hemisphere, and sex, and association with cognitive performance
No full textONKOPLASTİK MEME CERRAHİ TEKNİKLERİNİN TEMELLERİ
No full textOncoplastic Breast Surgery (OPBS) aims to achieve oncological safety and improved aesthetic out-comes. The text discusses various OPBS techniques categorized into Level I and Level II based on the extent of breast tissue removal. Level I techniques focus on creating wide flaps around the tumor, while Level II techniques are specialized for different tumor locations within the breast quadrants. The text highlights specific OPBS methods such as Racket Mammoplasty, Batwing (Omega) Technique, Gri-sotti Mastopexy, Donut Mastopexy, Crescent Mastopexy, Central Quadrantectomy, S-Mammoplasty, V-Mammoplasty, and more, detailing their surgical procedures and implications according to locations of tumors. The comprehensive overview delves into the importance of meticulous patient selection, surgical planning, and adherence to OPBS principles rooted in patient safety and cosmetic outcomes. Moreover, the text explores the significance of achieving clear oncological margins while addressing patient preferences and tumor characteristics. Emphasis is placed on the impact of OPBS on resection margins, re-excision rates, local recurrence, oncologic outcomes, complications, and cosmetic results compared to standard breast-conserving surgery and mastectomy. The overall effectiveness of OPBS ensures the balance between oncological efficacy and aesthetic satisfaction in breast cancer patients, ultimately improving patient outcomes and reducing the need for additional surgeries.</div
Integrated geophysical assessment of engineering site and subsurface structures: A case study in Kocaeli-Yazlık region, Turkiye
No full textThis study applied three geophysical methods to delineate the lithology, velocities, elastic moduli of the shallow subsurface layers, classify the site, and assess the geophysical parameters with depth of the engineering site in the Kocaeli-Yazl & imath;k region of T & uuml;rkiye. The applied methods included 2D Seismic Refraction Tomography (SRT), 1D multichannel surface wave analysis (MASW), and electrical resistivity tomography (ERT). A nearby borehole data revealed a three-layer structure: a 15 m thick alluvial layer of clay, silt, and sand; an intermediate claystone unit (Aslanbey Formation) between 15 and 35 m; and a deeper volcanic basement (Sar & imath;su volcanics) beyond 35 m. The 2D SRT and MASW velocity models showed a strong correlation with this stratigraphy. In the upper 15 m, low P-wave (750-975 m/s) and S-wave (160-180 m/s) velocities indicated saturated, unconsolidated alluvium, consistent with the borehole. Between 15 and 35 m, both P- and S-wave velocities increased (to 1600-2100 m/s and 250-290 m/s), reflecting the transition to compacted claystone, again aligning with the borehole log. The m values of the 1D MASW ranged from 203.5 to 314.6 m/s, confirming the presence of weak, heterogeneous near-surface materials. According to NEHRP (BSSC, 2020) and TBEC (2018), the site is classified as D (medium stiff soil) and ZD (medium stiff to stiff rock), further supported by borehole correlations. The calculated elastic moduli and geotechnical parameters revealed an increasing material competence with depth, characterized by higher stiffness and bearing capacity in deeper layers, consistent with the claystone and volcanic basement observed in the borehole. The ERT results also supported this model, showing low resistivity values (1-25 Omega.m for Wenner configuration and 1-40 Omegam for Schlumberger configuration) down to similar to 30-34 m, typical of saturated alluvium and clay. These resistivity values closely align with the seismic velocities, reinforcing the presence of unconsolidated, water-rich deposits. Across all methods, the borehole data provided essential validation, confirming that the integrated geophysical approach reliably characterized the subsurface layers and their geotechnical properties
Effect of thermo-mechanical treatments on the structural properties and tribological behavior of precipitation hardenable Cu-4Ti (wt%) alloy
No full textCu-4Ti alloy was solution annealed at 900 degrees C for 1 h and water-quenched followed by direct aging (variant I) or aging after 50 % cold rolling (variant II) at 450-600 degrees C for 1-420 min. Microstructure, hardness and wear properties were studied. Variant I yielded uniform beta'-Cu4Ti precipitates, reaching 240 HV after 120 min. at 500 degrees C and narrowing wear tracks to 540 mu m2 with 4 mu m penetration depths. Variant II attained 300 HV in 15 min, yet its dislocation-rich gradient microstructure promoted over-aging, beta-Cu3Ti coarsening and partial recrystallization, expanding grooves beyond 1 mm2 despite higher hardness. ANOVA confirmed temperature as dominant wear driver. Overall, variant I offers best hardness-wear compromise, whereas variant II provides only optimized short aging
Aşı Karşıtı Olan veya Aşı Tereddüdü Yaşayan Ebeveynlerin Çocukluk Çağı Aşıları Hakkındaki Görüşleri, Kaygıları ve Deneyimlerinin İncelenmesi
No full textSystemic Inflammatory and Oxidative–Metabolic Alterations in Rosacea: A Cross-Sectional Case–Control Study
No full textBackground/Objectives: Rosacea increasingly appears to involve systemic immune and metabolic disturbances rather than isolated cutaneous inflammation. To evaluate inflammatory, platelet, and oxidative–metabolic biomarkers in rosacea and explore their interrelations. Methods: 90 patients with rosacea and 90 healthy controls were evaluated for hematologic inflammatory indices—neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune–inflammation index (SII), pan-immune–inflammation value (PIV), mean platelet volume (MPV), and C-reactive protein (CRP)—along with oxidative–metabolic regulators including sirtuin 1 (SIRT1), sirtuin 3 (SIRT3), visfatin, and irisin. Logistic regression and receiver operating characteristic (ROC) analyses were used to identify independent predictors of rosacea, while inter-marker associations were evaluated using Spearman’s rank correlation. Results: Rosacea patients showed higher NLR, PLR, SII, PIV, MPV, CRP, and LDL cholesterol (p < 0.05) and lower SIRT1, SIRT3, visfatin, and irisin (p < 0.01). MPV independently predicted rosacea (OR = 7.24; AUC = 0.827), whereas SIRT1 inversely correlated with disease risk. SIRT1, SIRT3, and visfatin showed inverse correlations with HbA1c and waist-to-height ratio, while fasting glucose and HOMA-IR remained within normal ranges. Conclusions: Rosacea exhibits dual systemic activation, an inflammatory–platelet and an oxidative–metabolic axis bridging immune dysregulation, mitochondrial stress, and vascular dysfunction. Recognition of these pathways highlights the potential of redox-targeted and metabolic interventions beyond symptomatic treatment
Experimental and Numerical Analysis of Deep Cryogenically Treated Weldox700 Steel Used Hatch Opening Crane Hooks
No full textMedium-term outcomes and prognostic factors after transcatheter paravalvular leak closure: an international prospective multicentre registry
No full textBACKGROUND: Medium- and long-term outcomes after transcatheter paravalvular leak (PVL) closure remain poorly documented, with limited prospective data on predictors of morbidity and mortality. AIMS: This study aimed to assess medium-term outcomes and identify key predictive factors of mortality or surgical reintervention at 2 years after transcatheter PVL closure. METHODS: The prospective Fermeture de Fuite ParaProthétique (FFPP) Registry included consecutive symptomatic patients undergoing transcatheter PVL closure across 24 European centres between 2017 and 2019. Predictive factors for mortality and surgical reintervention were analysed over a 2-year follow-up. RESULTS: A total of 213 symptomatic patients underwent 237 procedures. The mean age was 68±11 years, with a median European System for Cardiac Operative Risk Evaluation (EuroSCORE) II of 6 (interquartile range [IQR] 4-10). PVL involved the mitral valve in 64.6% of cases and mechanical prostheses in 53.3%. Heart failure and haemolytic anaemia were present in 89.5% and 49.8% of patients, respectively. The transapical approach was used in 6.8% of cases. Technical success was achieved in 87.3% of procedures, and clinical success at 1 month was achieved in 70.5% of patients. The median follow-up was 24.4 months (IQR 23.2-26.4). The survival rate at 2 years without the need for surgical reintervention was 66.1% (95% confidence interval [CI]: 60.1-72.7). Multivariate analysis identified mitral PVL, mechanical valves, and haemolytic anaemia as independent risk factors for adverse outcomes during follow-up. The absence of clinical success at 1 month was the strongest predictor of adverse outcomes (hazard ratio 5.00, 95% CI: 2.70-9.09; p=0.001). CONCLUSIONS: Transcatheter PVL closure offers a durable therapeutic option for high-risk patients when early clinical success is achieved. Mitral valve involvement, mechanical prostheses, and haemolytic anaemia remain key predictors of poor outcomes over a 2-year follow-up