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SODYUM β-ALANİNAT ÇÖZELTİSİ İLE KARIŞTIRMALI HÜCRE SİSTEMİNDE KARBON DİOKSİT ABSORPSİYONU
No full textInfluence of Cu on phase formation, hardness, and magnetism in high-entropy alloys
No full textIn this study, the effects of Cu addition on the phase evolution, microstructure, and elemental distribution of Al1.5Co4CuxFe2Mn1.5 (x = 0, 0.1, 0.5, and 1.0) high-entropy alloys were systematically investigated. In addition, nanoindentation, magnetic properties, atomic force microscope, and magnetic force microscope analysis were carried out. XRD analysis revealed that some HEAs have BCC, FCC, and Laves phases. SEM and EDS images show that the alloys solidify in different ways depending on the Cu content, with grain structures becoming finer and secondary phases forming. Furthermore, it was revealed that the mechanical properties of the alloys change as the Cu content increases. The maximum Cu content (Cu10) peaked at 12.15 GPa nano hardness and 423.9 GPa elastic modulus. Magnetic saturation decreased and coercivity increased as the Cu content increased. The Cu0 alloy was found to have a saturation of 143 emu/g and a coercivity of 1.5 Oe. According to MFM analyses, as the Cu content increased, the ratio of the phase with high ferromagnetic interaction strength in the alloys decreased
Evaluation of difficult-to-treat rheumatoid arthritis using EULAR definition: Prevalence and clinical determinants from a single-center cross-sectional study
No full textIn 2021, the European Alliance of Associations for Rheumatology (EULAR) introduced standardized criteria to define difficult-to-treat rheumatoid arthritis (D2T RA). This study aimed to examine the prevalence and clinical features of D2T RA within a real-world cohort. This study included 72 RA patients followed at Gazi University Rheumatology Clinic for a minimum of one year between May 2021 and August 2022. Data on sociodemographic parameters, disease activity, therapeutic history, and functional status were collected. All participants were assessed using validated instruments for fibromyalgia (2016 American College of Rheumatology criteria), neuropathic pain (DN4), mood symptoms (HADS), pain catastrophizing (PCS), and physical function (HAQ). The overall prevalence of D2T RA was found to be 6.9%. Compared to the non-D2T group, patients meeting D2T criteria exhibited longer disease duration, higher inflammatory activity, reduced functional capacity, and greater exposure to B-cell–targeted therapies. These findings underscore the critical role of individualized treatment strategies in managing D2T RA
Vascular calcification in Takayasu arteritis: relationship with metabolic syndrome, left ventricular mass index, and intima-media thickness.
No full textObjective: The present study aims to determine the frequency of vascular calcification in Takayasu arteritis (TA) and the risk factors for it and to evaluate its relation with atherosclerotic predictors such as metabolic syndrome (MS), left ventricular mass index (LVMI) and carotid intima-media thickness (CIMT). Methods: A cross-sectional study was conducted in patients with TA; MS was defined according to the US National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATP III) criteria. The study included 49 TA patients (22 with MS, 27 without MS) and 31 healthy controls (HCs). Non-contrast computed tomography measured calcification in coronary arteries, aorta, and branches. Results: Forty-seven patients (95.9%) were female and mean age was 33.45 ± 8.53 years. Total calcification score (mean ± SD; 5223.9 ± 18041.1 AU vs. 35.87 ± 72.70 AU (p = 0.05)), CIMT, and LVMI were found to be significantly higher in TA patients than HCs (p < 0.05). While there was no significant difference between the total calcification score of MS (+) TA patients and MS (−) TA patients, in both patient groups, the total calcification score was found to be significantly higher than HCs. MS (+) and MS (−) groups were found to have significantly higher CIMT and LVMI values than the control group, in addition, MS (+) patients were found to have significantly higher LVMI and CIMT values than MS (−) group (p < 0.05). Conclusion: Vascular calcification, CIMT, and LVMI are elevated in all TA patients, with greater impact in the presence of MS
Additive manufacturing of geopolymer composites for sustainable construction: critical factors, advancements, challenges, and future directions
No full textIncreasing pollution poses enormous pressure on the global ecosystem, with a need to limit the carbon emissions from the construction materials industry. Mitigation of this carbon is possible by converting industrial wastes into alternative cement and optimisation in the building process. Taking this into account, advancement is taking place in sustainable geopolymer composites-based additive manufacturing (AM) technology. Typical precursors for geopolymer binder are industrial waste by-products (such as slag, fly ash, and metakaolin). In another aspect, AM entails several benefits such as easy fabrication, freedom of design, the ability to generate sophisticated structural elements and reduce: expenses, time, waste generation, and labor demands. This review journal paper on geopolymer AM presents a bibliometric study followed by an overview of AM methods and influencing parameters, techniques in geopolymer AM (such as extrusion and powder bed), materials, improvements in AM process, and fresh-state and hardened-state properties. Recent developments in AM processes within the geopolymer are critically discussed while investigating the properties and applications of the same. The discussion includes an analysis pinpointing research gaps essential in developing geopolymer AM. Graphical abstract: (Figure presented.
Seismic Testing and Modeling of Full-Scale Substandard RC Columns Retrofitted with Sprayed GFRM with and without Basalt Mesh under High Axial Compression and Shear Demand
No full textThis study presents the experimental and analytical hysteretic behaviors of eight full-scale RC square and rectangular columns. The columns were designed to have different shear spans that represent: (1) a column that complies with the Turkish Government Ministry of Reconstruction and Resettlement’s ( 1975) seismic design code, Turkish Seismic Design Code (TSDC); (2) a substandard column; and (3) two sprayed glass fiber–reinforced mortar (GFRM)-retrofitted counterparts of the substandard column with and without basalt mesh. The substandard columns were designed to be subjected to relatively high shear ratios (i.e., the ratio of the shear force that corresponds to the moment capacity to shear strength of the cross section) up to 0.85 and with a high axial load-to-capacity ratio of 0.75. All columns were tested under constant axial load and reversed cyclic lateral displacement excursions. The results revealed that the columns that complied with the TSDC showed satisfactory behavior for seismic performance, and the performance of the substandard columns was extremely poor. However, the hysteretic performance of the substandard columns that were subjected to high axial stress and shear significantly improved after the proposed retrofitting. Finally, a numerical model was developed in OpenSees to reproduce the hysteresis curves of the specimens. The slip of the longitudinal bars at the column–foundation interface, strain penetration into the foundation, and buckling of the longitudinal bars in compression were accounted for in the modeling. The results are in good agreement with the experimental hysteresis curves. The performance levels of the columns are further specified, and the predictions of the current seismic codes were analyzed: (1) the European Committee for Standardization’s 2005 code, Eurocode 8: Design of structures for earthquake resistance; Parts 1–3: Strengthening and repair of buildings (EC8-3); and (2) the Turkish Government Ministry of Interior Disaster and Emergency Management Authority’s 2018 code, Turkish Building Earthquake Code (TBEC). The TBEC provided more accurate estimates of plastic rotation capacities for substandard specimens. In contrast, EC8-3 overestimated the plastic rotation capacity when shear stresses were relatively high due to lower shear span-to-depth ratios (a/d).</p
Güncel Üroloji Çalışmaları VII- İnkontinans
No full textAşırı aktif mesane (AAM), idrar yolu enfeksiyonu ya da anatomik bozukluk olmaksızın aciliyet hissi, sık idrara çıkma, noktüri ve bazen sıkışma tipi idrar kaçırma ile karakterize bir sendromdur. Kadın ve erkeklerde yaygın görülür, prevalansı yaşla artar. Patofizyolojisi nörojenik, miyojenik ve ürotelyal hipotezlerle açıklanır. Tanı, ayrıntılı anamnez, fizik muayene, laboratuvar testleri ve gerekirse ürodinami ile konur. Tedavi basamaklı şekilde ilerler: yaşam tarzı değişiklikleri ve egzersizler, antikolinerjik ilaçlar ve β3 agonistler, botulinum toksin enjeksiyonları, PTNS ve sakral nöromodülasyon ve nadiren cerrahi yöntemler uygulanır. Etkili bir yönetim için semptomlara neden olabilecek diğer durumlar dışlanmalı ve bireye özgü yaklaşım benimsenmelidir.Overactive bladder (OAB) is a syndrome characterized by urinary urgency, frequent urination, nocturia, and sometimes urgency incontinence, without the presence of urinary tract infection or structural abnormalities. It is common in both men and women, with prevalence increasing with age. Its pathophysiology is explained through three main hypotheses: neurogenic, myogenic, and urothelial. Diagnosis is made based on a thorough history, physical examination, laboratory tests, and, when necessary, urodynamic studies. Treatment follows a stepwise approach: lifestyle modifications and exercises, anticholinergic drugs and β3 agonists, botulinum toxin injections, percutaneous tibial nerve stimulation (PTNS), and sacral neuromodulation and in rare cases, surgical interventions. For effective management, other possible causes of similar symptoms must be excluded and a personalized treatment plan should be implemented.</p
