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A life-threatening cause of stridor, primary tracheal actinomycosis
No full textActinomycosis is a chronic, suppurative infection caused by Actinomyces israelii, an anaerobic bacterium that is part of the normal oral flora. A 47-year-old woman presented to the clinic with dyspnea and sore throat. Computed tomography(CT) revealed thickening of the proximal tracheal lumen and airway narrowing. Pathological examination of biopsy specimens obtained by rigid bronchoscopy revealed periodic acid-Schiff (PAS)(+) bacterial colonization with filamentous bacilli, consistent with Actinomyces. This report describes an uncommon presentation of tracheal actinomycosis in which tracheal dilatation was performed for both diagnostic sampling and therapeutic management of tracheal stenosis
Influence of pin-fin layout on transient saturated flow boiling in expanding micro heat sinks
No full textInteractions among liquid phase, vapor bubbles and geometrical structures along the flow path strongly affect thermo-fluidic mechanisms for flow boiling in micro-spaces. Therefore, in a micro-pin-finned system, layout of pin-fins has great potential for improvement of thermal performance in such systems. As a first investigation in literature, here, role of pin-fin layout on transient saturated flow boiling conditions being performed in expanding micro heat sinks under variable heating powers was conducted. Four different pin-finned heat sinks (PF1, PF2, PF3, PF4), one of which is the reference case (PF1, having uniform fin distribution), were tested for two mass velocities (159 and 256 kg m-2 s-1). For each experimental run, a variable heating power (147W, 252W, 195W, 290W, 147W) sequence was applied. Discussion was improved by flow images. Contribution of effective forces changes based on the pin-fin distribution, and this variation plays a critical role in flow boiling performance. Under both mass fluxes, at each heating power value, the highest values of htp (abbreviation of two-phase heat transfer coefficient) are obtained for PF4. For 147W and 159 kg s-1 m-2, the average htp of PF4 is approximately 85%, 41%, 45% higher than that calculated for PF1, PF2 and PF3, respectively. It is concluded that PF4 is the optimal choice. PF4 is distinctly superior in terms of heat transfer performance, provides the highest PEC value at low mass flux, and offers the second-highest PEC value at high mass flux, with a magnitude comparable to that of PF2
Çay yaprağının Alımı ve Nakliyesi
No full textÇay Tarımı Dersi 15. Hafta Ders Notu Konusu : Çay yaprağının Alımı ve Nakliyes
Foundations of Pattern Mining: Concepts, Techniques, and Methods
No full textData Mining 6. Hafta Ders Notu Konusu : Foundations of Pattern Mining: Concepts,
Techniques, and Method
Nonlinear group and phase velocity analysis and architectural design of functionally graded tapered plates under supersonic airflow
No full textIn this research, we study the nonlinear group of phase velocity and the architectural design of functionally graded plates with variable thickness in the presence of supersonic airflow. The plates are modeled as three-directional functionally graded materials (TD-FGMs) using a quasi-3D refined theory (Q3D-RT) to capture a full representation of the interactions between the materials' properties, geometry, and loading conditions. The nonlinearities of the system are described via Von-Karman's geometric nonlinearity, subject to the constitutive equations that are modified for viscoelastic solids, where the time derivative of strain is explicitly included. The analysis encompasses several forms of aerodynamic pressure to model the supersonic flow field, including dynamic unsteady Bernoulli-type pressure, nonlinear dynamic pressure including strain coupling, krumhaar’s modified supersonic piston theory, and the viscoelastic dynamic lag model. The neural network-nerodynamic hybrid pressure model is evaluated as the most accurate model for supersonic airflow conditions. The research utilizes Hamilton’s principle to derive the governing equations before they are solved using the harmonic balance technique, along with a numerical iterative method to achieve good accuracy of the results. As part of the examination of the accuracy of the current work, the results will also be compared with the results from finite element simulations. The results analyze the effect of different material gradation, plate thickness, and supersonic airflow conditions on the dynamic response and stability of the structure. The results add new knowledge in the design and functional performance of functionally graded plates in aerospace applications, where considerations of both material nonlinearity and complex aerodynamic interactions must be taken into account. The method also provides a practically applicable framework for both analysis and design of advanced structural components, experienced with unique multi-physics situations, subject to supersonic environments. The method has potential applications in advanced aerospace vehicle development
Translation, adaptation and identity: the role of literature in Georgia’s Europeanization process (19th-century perspective)
No full textDuring the first half of the nineteenth century, Georgia experienced a complex process of Europeanization that reshaped its cultural and literary landscape. In this period, marked by the country’s incorporation into the Russian Empire, Georgian writers engaged with French and Russian literary traditions through translation, adaptation, and rewriting. This article examines how three key figures—Aleksandre Chavchavadze, Grigol Orbeliani, and Grigol Rcheulishvili—used translation not simply as a means of linguistic transfer but also as a tool for negotiating identity and cultural autonomy under imperial pressure. Drawing on postcolonial theory, comparative literature, and contextual analysis, this study explores how translated texts were creatively reconfigured to reflect local historical consciousness and ideological priorities. The findings show that translation functioned as a form of cultural resistance and hybrid expression, enabling Georgian authors to incorporate Enlightenment ideals, Romantic esthetics, and new genres while embedding them in native literary forms. Aleksandre Chavchavadze’s engagement with French classics, Grigol Orbeliani’s national rewriting of Russian poetry, and Grigol Rcheulishvili’s localization of European prose all exemplify how foreign influences were rearticulated through a distinctly Georgian lens. The article argues that these practices contributed to the emergence of a modern literary language and national subjectivity in Georgia. Rather than passive reception, the Europeanization of Georgian literature was shaped by active strategies of adaptation and ideological reinterpretation. This study contributes to postcolonial literary scholarship by demonstrating how peripheral literary systems employed translation as a medium of cultural self-determination during periods of asymmetrical power relations
Data Warehouses and Analytical Query Processing
No full textData Mining Dersi 4. Hafta Ders Notu Konusu : Data Warehouses and Analytical Query Processin
Ni- and Co-doped TiO2nanofibers for enhanced antibacterial and antibiofilm activities, and mechanistic insights
No full textNowadays, with the growing need for alternative antibacterial materials for the treatment of bacterial infections, TiO2 with antibacterial properties has attracted attention as a potential antibacterial agent. Ni-TiO2 and Co-TiO2 nanofibers (NFs) were synthesized via an electrospinning process. The antibacterial activities of these NFs against S. aureus and E. coli were evaluated under UV-light illumination using optical density measurements. Co-TiO2 exhibited superior antibacterial activity against both S. aureus and E. coli under UV-light irradiation. The antibacterial mechanism was further investigated through a glutathione (GSH) oxidation assay and morphological analysis using scanning electron microscopy (SEM). Hydrophilicity was evaluated by contact angle measurement. The antibiofilm activities of TiO2, Ni-TiO2, and Co-TiO2 NFs were investigated with respect to E. coli and S. aureus biofilms. Ni-TiO2 and Co-TiO2 demonstrated more effective antibiofilm activities than bare TiO2. Under UV-light irradiation, the biofilm inhibition efficacy was increased for both Ni-TiO2 and Co-TiO2 NFs while Co-TiO2 NFs were found to have the greater antibiofilm performance. Additionally, in silico analysis was conducted to explore the molecular interactions of the NFs with S. aureus Immunoglobulin-Binding B Domain (PDB ID: 1BDD) and FimH lectin protein of E. coli (PDB ID: 4XO8). Co-TiO2 exhibited stronger binding to S. aureus, while TiO2 showed stronger binding to E. coli
Executive dysfunction and psychological symptoms in problematic social media use
No full textThis study aimed to investigate the relationship between problematic social media use (PSMU), executive functions, depression, anxiety, stress, and sleep quality in a healthy adult population. A total of 174 adults (62.6% female, mean age = 37.19 +/- 9.17 years) were recruited online. Participants completed a sociodemographic data form, the Bergen Social Media Addiction Scale (BSMAS), the Executive Function Index (EFI), the Depression Anxiety Stress Scale-21 (DASS-21), and the subjective sleep quality subscale of the Pittsburgh Sleep Quality Index (PSQI). Pearson correlations were conducted. Problematic social media use showed negative associations with executive functioning, particularly with organization (r = -.423, p < .001). In addition, BSMAS scores were positively correlated with depression (r = .354, p < .001), anxiety (r = .217, p < .001), and stress (r = .233, p < .001). The findings indicate that PSMU is strongly linked to executive function and psychological distress. These results highlight the need for interventions targeting cognitive regulation, emotional well-being, and healthy technology use
Resilience-oriented seismic retrofit of heritage masonry minarets using hybrid base isolation and supplemental damping
No full textHistoric masonry mosques represent a highly vulnerable class of cultural heritage structures whose seismic fragility stems from their complex geometries, heterogeneous material composition, and rigid load-transfer mechanisms. This study presents a resilience-oriented seismic performance improvement of the historic masonry minaret of the Bayburt Grand Mosque, a structure with limited lateral deformation capacity that challenges the applicability of conventional strengthening measures. To address this limitation, a hybrid retrofitting strategy is introduced, integrating lead rubber bearings (LRBs) with supplemental viscous dampers (VDs) at the foundation level. This combined system-implemented for the first time in a historic masonry minaret-aims to enhance energy dissipation and displacement control through a minimally invasive and architecturally compatible approach. Finite element analyses (FEA), coupled with MATLAB-supported optimization routines, were used to calibrate isolator stiffness and damper coefficients. Three configurations were evaluated: fixed-base, LRB-isolated, and hybrid LRB-VD systems. Nonlinear time-history analyses (NTHAs) using the 1992 Erzincan (Otlukbeli) earthquake record quantified displacements, stress-strain responses, and damage progression. Results show that while base isolation mitigates seismic demand, it remains insufficient under restricted deformation capacity. The proposed hybrid system reduces peak horizontal displacements from 22 cm to 12 cm, limits drift ratios below 0.17 %, and lowers maximum tensile stresses from 4.890 MPa to 0.490 MPa-well below the masonry tensile strength of 0.880 MPa. Two iterative analytical design methodologies are additionally introduced to derive effective isolator stiffness and viscous damping coefficients, enabling systematic integration into resilience-focused evaluation frameworks. Overall, the study advances reliability-based, conservation-compatible retrofitting practices for historic masonry minarets and supports sustainable strategies for seismic risk mitigation