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Mechanical properties and displacement capacity of welded-plate flexural yielding dampers
No full textReplaceable hysteretic steel dampers can be installed at the ends of diagonal braces to provide passive energy dissipation in frame-type structures. These dampers must satisfy both strength and displacement requirements. Previous studies have primarily focused on small-scale component testing, with limited investigation into the performance of large-scale dampers, particularly through sub-assemblage testing. This paper presents the findings of a combined experimental and numerical study on the mechanical properties and displacement capacity of welded-plate flexural yielding dampers. The experimental program was carried out in two phases: the first involved component testing of five specimens, while the second involved sub-assemblage testing of two specimens. Key variables included the number of yielding plates, plate length, plate thickness, and steel grade. Results from the first phase demonstrated that welded-plate flexural yielding dampers can achieve yield and ultimate resistances of 626 kN and 891 kN, respectively, with deformation capacities exceeding 40 mm. In the second phase, sub-assemblage tests showed that braces equipped with welded-plate flexural yielding dampers could accommodate story drifts of 2.63 % with single dampers and 5.5 % with dual dampers. Finite element analysis was used to simulate the behavior of the specimens and to develop a failure criterion for damper design. An expression was developed to calculate displacement capacity based on geometric variables. Both experimental and numerical results confirm the suitability of welded-plate flexural yielding dampers for seismic applications, offering a reliable and efficient energy dissipation mechanism for braced frame structures
The light detection performance of the Al/DCJTB/n-Si Schottky type photodetector for a wide-range spectrum
No full textThe 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) is a red fluorescent dye known for its high luminescence efficiency, color purity, and resistance to concentration quenching. DCJTB was applied as an interfacial layer between Si and Al via spin coating to investigate its effect on Schottky photodetector performance at various light intensities and wavelengths (UV-Vis-NIR). Structural and optical properties of the DCJTB layer were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet-visible (UV-vis) spectroscopy. Current-voltage (I-V) and current-time (I-t) measurements revealed that the Al/DCJTB/n-Si heterojunction exhibits an ideality factor (n) of 3.15 and a barrier height (Phi b) of 0.701 eV under dark conditions. With increasing illumination (20-100 mW/cm2), n varied from 3.884 to 3.077, while the barrier height increased slightly. The device achieved a responsivity (R) of 0.63 A/W and a specific detectivity of 1.63 x 1010 Jones under sunlight. The external quantum efficiency (EQE) reached 0.68 % at 550 nm, confirming high sensitivity in the green region, while performance declined beyond 700 nm. These findings demonstrate that the Al/DCJTB/n-Si heterojunction is most effective in the visible spectrum, making it promising for optoelectronic and photodetection applications
Development of hybrid gaseous detectors
No full textIn order to address the issue of future implementation of gaseous detectors due to large global warming potentials of some common detector gases, our team has developed the concept of "hybrid gaseous detectors" where part of the electron multiplication is transferred from the gas layer to a solid-state layer applied directly on the in-chamber anode surface. The concept was tested with the RPCs and was validated to relax the operating conditions considerably enabling the consideration of alternative gases and flow schemes. For the developed hybrid RPCs, Al2O3 and TiO2 were used as high secondary electron emission yield surface coatings on the anode. Afterwards, we adapted the hybrid concept to drift tubes. First tests have shown promising results. Recently, we developed hybrid RPCs with optical readout which is obtained with SiPMs directly coupled to the gas layer. Here, we report on the development of hybrid gaseous detectors and discuss future directions
Climate change-driven risks on contamination routes and timing, and phage control of Salmonella on leafy greens
No full textThis study investigated the persistence and control of S. enterica serovar Newport on garden cress under warming temperature scenarios (15°C, 17°C, 19°C, 21°C), simulating climate change-relevant conditions. Two contamination routes—seed and irrigation—were tested with irrigation applied at different plant growth stages to assess the impact of contamination timing too. In addition, the study evaluated the effectiveness of preharvest bacteriophage irrigation applied at various intervals prior to harvest. Results showed that both contamination routes supported long-term survival, with the greatest persistence at 15°C. Late-stage contamination through irrigation resulted in higher bacterial loads at harvest, posing greater food safety risks. While a washing step significantly reduced Salmonella levels, especially in later contamination scenarios, it was insufficient to fully remove strongly attached bacterial populations across all cases. Bacteriophage irrigation achieved up to 2.2 log MPN/g reduction when applied close to harvest, particularly when combined with washing. Beyond expanding the mechanistic understanding of Salmonella-plant interactions, these findings illustrate how temperature dynamics, contamination timing, and exposure routes collectively influence bacterial persistence under warming scenarios relevant to climate change, while also demonstrating the potential of a targeted preharvest intervention strategy with significant control efficacy
Exploring the genetic landscape of COVID-19 susceptibility and severity among patients in Türkiye
No full textBackground: One of the most challenging factors for clinicians in managing COVID-19 has been differences in the clinical course. To investigate the parameters associated with severe disease in detail, along with examining known risk factors such as advanced age and comorbidities, understanding personal genetic factors is necessary, as the clinical course may change due to differences in the host genome. Methods: Human genetic variants reported to be associated with severe disease were genotyped in 68 patients in COVID-19 medical wards and 52 in COVID-19 intensive care units at Hacettepe University Adult Hospital. Results: The rs17860115 variant was significantly more prevalent in our cohort than in the European (non-Finish) population, whereas the rs2298659, rs2298661, rs4290734, and rs9271609 variants were significantly less common, which may reflect genetic differentiation, selective pressures, or protective factors within this population. While no significant association was found between variants and disease severity, notably, the ACE2 rs1548474 allele frequency was 38.0% in the ICU group and 22.9% in the non-ICU group (OR = 2.06; 95% CI 1.10–3.90; p = 0.02). Conclusion: These findings emphasize the importance of examining genetic differences both within and across populations when developing new strategies for disease control and public health policies, particularly for infectious diseases such as COVID-19. They also point to the necessity for further research involving larger and more varied populations to validate these associations and to investigate the genetic factors that may drive them
Metaphysics and Aesthetics of Decoration: Ornamental Thinking
No full textIn his “Repetition of Difference in Ornament,” Jakub Mácha demonstrates how Gilles Deleuze’s notion of ornament plays a vital role in his metaphysics and semiotics. This chapter will follow upon Mácha’s work by examining the importance of ornament in Deleuze’s aesthetics. The broader claim is that when we take into account Deleuze’s explicit thinking on play, we may find it operating implicitly in other facets of his philosophy, with one possible instance being his writings on ornament. First, this chapter briefly draws upon Mácha to define ornament for Deleuze. Then, it delineates one aspect of Deleuze’s philosophy of play, namely, creative gambling. Finally, it examines how these conceptions operate in specific cases where Deleuze discusses ornament in aesthetic contexts, especially (1) in his study of repetition in Caduveo decorative motifs, (2) in his and Félix Guattari’s portrayal of birdsongs and displays as “fuzzy aggregates,” and (3) in his application of Wilhelm Worringer’s “Northern ornament” in his study of Francis Bacon’s paintings. In all, for Deleuze, ornamental play’s activity is not repeating inconsequential and homogenous supplementations but rather continually generating heterogeneities with the power to deform compositions
Understanding Squeezed States of Light Through Wigner's Phase-Space
No full textThis paper starts with the transition from classical physics to quantum mechanics which was greatly aided by the concept of phase space. The role of canonical transformations in quantum mechanics is addressed. The Wigner phase-space distribution function is then defined which arises from the formulation of the density matrix, followed by the harmonic oscillator in phase space. Coherent and one- and two-mode squeezed states of light as well as the squeezed vacuum are discussed in the phase-space picture. Attention is also drawn to the fact that squeezed states naturally generate entanglement between the two-modes. Coupled harmonic oscillators are also elucidated in connection with the Wigner phase space. Note that the phase-space picture of quantum mechanics has become an important scientific language for the rapidly expanding field of quantum optics. Here, we mainly focus on the simplest form of the Wigner function, which finds application in many branches of quantum mechanics. We make use of several symmetry groups such as Lorentz groups, the symplectic group in two and four dimensions, and the Euclidean group. The decoherence problem of an optical field is examined through a reformulation of the Poincar & eacute; sphere as a further illustration of the density matrix
The promotional effect of gallium loading on the bifunctional Cu–Ga/γ-Al2O3catalyst for CO2hydrogenation to methanol and dimethyl ether at atmospheric pressure
No full textHydrogenation of CO2 to methanol and dimethyl ether (DME) was investigated over gallium-promoted copper catalysts supported on γ-Al2O3 (Cu–Ga/γ-Al2O3) at atmospheric pressure—conditions under which Ga-promoted Cu/γ-Al2O3 catalysts have not been investigated before. Reaction parameters—including temperature, H2 : CO2 feed ratio, and gas hourly space velocity (GHSV)—were optimized prior to evaluating the effect of Ga loading. Catalysts with varying Ga loadings (5, 10, 12, and 15 wt%) were tested, with the 5 wt% Ga catalyst achieving the highest combined formation rate of methanol and DME at 246 μmolcarbon gcat−1 h−1 and a combined selectivity of 20.6% under optimal conditions (220 °C, 9 : 1 H2 : CO2, GHSV = 30 000 mL gcat−1 h−1), where the DME production rate was twofold that of the Ga-free catalyst. For comparison, a commercial Cu/ZnO/Al2O3 catalyst was synthesized and showed a significantly lower methanol selectivity (7.2%) and formation rate (60 μmol gcat−1 h−1) under identical operating conditions, with no DME production observed. The promotional effect of Ga was further explored using periodic density functional theory (DFT) calculations on a Cu4/β-Ga2O3(001) model. Theoretical results suggest that CO2 hydrogenation proceeds primarily via a carboxyl intermediate, rather than through formate or CO pathways
The role of immunohistochemical CIC expression in oligodendrogliomas for recurrence risk stratification
No full textOligodendrogliomas (ODG) account for ' 5-7% of neuroepithelial tumors. Since the 2016 World Health Organization classification, ODG have been defined by IDH mutation and 1p/19q co-deletion, a genetic profile typically linked with classic oligodendroglial morphology and better survival compared with astrocytic gliomas. Although this genotype is considered a favorable prognostic marker, a subset of ODGs shows early recurrence and aggressive behavior, highlighting the need for additional prognostic indicators. Capicua (CIC), located on chromosome 19q13.2, is a transcriptional repressor downstream of receptor tyrosine kinase signaling. Loss of CIC function increases neural stem cell proliferation, promotes oligodendrocyte progenitor specification, and activates proliferative pathways. Somatic CIC alterations have been reported in up to 70% of ODGs, nearly always in the setting of 1p/19q co-deletion. In this study, we investigated the prognostic value of CIC immunohistochemical (IHC) expression in a homogeneous cohort of IDH-mutant, 1p/19q-codeleted ODGs. Our results demonstrated that complete CIC expression loss and 19q polysomy greater than 22.5%, together with mitotic counts >= 6 per 10 highpower fields, were significantly associated with early disease recurrence. Although the absence of molecular confirmation of CIC alterations limits interpretation, the findings suggest that CIC IHC can serve as a surrogate marker to identify patients who may benefit from additional molecular analysis. Conclusion: CIC loss, 19q polysomy, and elevated mitotic activity may function as valuable prognostic indicators in ODGs. These features could improve risk stratification and guide personalized therapeutic strategies in otherwise favorable cases
TRCN100, High-Resolution Gridded Curve Numbers of Türkiye to Use in Hydrological Models
No full textAccurate estimation of runoff is essential for hydrological modeling, flood prediction, and water resource management. However, existing curve number (CN) data sets have limitations due to their relatively coarse resolution and reliance on generalized global data sets. To address these limitations, this study presents the first high-resolution TRCN100 (Türkiye Curve Number at 100 m resolution) data set, which includes detailed soil maps and land use data for Türkiye. The soil conservation service (SCS) method, developed by the United States Department of Agriculture (USDA), is widely applied to establish the rainfall-runoff relationship, with one of its key inputs being the CN. The CN can be calculated from land use/cover and soil data, and one study has already provided globally gridded CN data sets with an approximate 250-m resolution (GCN250). In this study, for the first time, both hydrologic soil group (HSG) and CN values at 100 m resolution (TRCN100) were generated for Türkiye by using detailed soil maps based on field measurements along with the Coordination of Information on the Environment (CORINE) land use/cover map under average antecedent runoff conditions (ARCII). TRCN100, derived from detailed field-based soil data, is digitally produced and available for use throughout the country, unlike previous local data sets. A comparative analysis of GCN250 and TRCN100 data sets was conducted across 25 river basins in Türkiye, revealing average differences of approximately +6% and -7% in cases with positive and negative differences, respectively. Also, runoff simulations produced using TRCN100 and GCN250 were compared with the global land data assimilation system (GLDAS), showing that TRCN100 performed better, with 21 out of 25 basins achieving higher Nash-Sutcliffe efficiency (NSE) scores. The results suggest that TRCN100, derived from higher resolution ground-based data, offers significant improvements for use in hydrological model studies for Türkiye. The development of this data set covering the whole country is crucial as it fills a significant gap in hydrological studies. The improved resolution and accuracy make it a valuable resource for flood risk assessment, watershed management, and hydrological modeling studies. Additionally, an interface was developed to retrieve TRCN100 values for the user-defined areas in Türkiye