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Critical structures such as hospitals, high-precision manufacturing facilities, telecommunications centers, and fire stations, especially, need to maintain their functionality even during severe earthquakes. In this sense, seismic isolation technology serves as a vital design method for preserving their functionality. Seismic isolators, also known as earthquake isolation systems, are used to reduce the effects of earthquakes on buildings by isolating them from the ground they are located on. By ensuring that less acceleration and force demand is transmitted to the superstructure, both the building and the equipment and the devices in the building are prevented from being damaged by earthquakes. This experimental study aims to conduct vibration tests on a small-scale multi-story steel-building model equipped with a specially designed rolling-type seismic base isolation system. The relationship between the test model and the prototype was achieved by frequency simulation. The tests will be performed on a shake table under six different earthquake accelerations to examine the model's dynamic behavior. The primary goal is to evaluate the isolation performance of the rolling-type seismic base isolator under seismic loads, with a focus on recording the vibrations at the top of the test building. It has been observed that the isolator placed at the base of the building significantly reduced the peak acceleration and displacement values of the floor motion. Under the most severe earthquake record applied to the shake table, the acceleration at the top of the building with the isolator was found to be reduced by approximately 50%, compared to the non-isolated case. [ABSTRACT FROM AUTHOR]

Objective: Constipation is often inadequately treated in childhood, which can lead to psychological problems. This study aimed to evaluate the adequacy of prescribed drugs, dosing, usage, and responses to these drugs in children with functional constipation. Methods: This research comprised children who had consulted a pediatric gastroenterologist for functional constipation and had previously undergone constipation therapy. The name of the drug used, duration of drug usage, method of measurement, and what they took the drug with, the dose of drug, and response to the drug were recorded. Results: Eighty-seven percent of the patients had received lactulose treatment. Only 31% of the patients received a medication dose greater than 1 mL/kg. In 58.3% of cases, the duration of drug use was shorter than one month. There was not a response in 62.9% of cases, a partial response in 23.1%, and a full response in 13.8% of cases. When the patients were compared based on response, there was a significant difference in the duration of drug usage, what they drank the drug with, the daily dose of the drug, and the daily dosage per weight of the drug. Patients who measured the drug using a milliliter scale responded better. The response to the drug increased as the drug dosage per weight increased. Response was obtained in 73% of patients who had no response or partial response after drug or dose adjustments. Conclusion: For a comprehensive response, parents must be carefully taught the dosage of the drug and how to measure it. [ABSTRACT FROM AUTHOR]

Synchrotron x-ray diffraction (SR-XRD) and X-ray absorption fine structure spectroscopy (XAFS) were used to investigate the crystal and electronic properties of boron-substituted CuFeO2 material at room temperature. Without boron substitution, the polycrystalline structures of the trigonal (rhombohedral) ' $R\bar{3}m$ R 3 ¯ m ' CuFeO2 (87.7%) and hexagonal 'P63/mmc' (12.3%), which were also present in each sample but in different proportions, were utilised to identify the base material. XRD patterns revealed that, beyond 10% boron substitution, the metal–oxygen bonds (Fe-O and Cu-O) weakened, resulting in the formation of new tetragonal 'I41/amd' CuFe2O4 crystals. Although the CuFeO2 structure was preserved, it is conceivable that the presence of other crystal structures could lead to the formation of new features. This state arose as a result of CuFe2O4 crystallization and the impact of boron activity on the surrounding oxygen structures. By measuring magnetisation at both swept temperatures (10–300 K) and applied magnetic fields (±30 kOe), the magnetic properties of the samples were investigated. In the 10–300 K temperature range, the polycrystalline samples exhibit a ferromagnetic property without a magnetic phase transition. This suggests that replacing B with Fe in CuFe1−xBxO2 does not influence the primary magnetic property of CuFeO2. The samples' saturation magnetisation (Ms) values gradually fall as the B substitution content increases with Fe. This is because there's a chance that the non-transition metal B in CuFe1−xBxO2 will boost antiferromagnetic superexchange Cu-O interactions while lowering the p-d exchange interaction. [ABSTRACT FROM AUTHOR]

In this study, the maximum isolator displacement (MID), maximum isolator force (MIF), and maximum acceleration (MA) values that occur at the isolation level in seismically isolated structures were investigated using the nonlinear response history analyses (NRHA) by considering four different scaling methods. Both horizontal components of the ground motion records scaled with different scaling methods were applied simultaneously to the isolation unit modeled with lead rubber bearing, and bi-directional analyzes were performed. In the analyses, lead rubber bearings were modeled with two different approaches as the case deterioration due to the heating effect in the lead core is considered (Temperature Included, TI) and the case it is not considered (Boundary Analysis, LB-UB). In the analyses, four different Q/W ratios (0.75, 0.90, 0.105, and 0.120) representing the isolation unit strength, and five different Tiso (2.5s, 2.75s, 3.0s, 3.25s, and 3.5s) representing the isolation period were taken into account. As a result, while the variation in the scaling methods does not create a significant change on the maximum isolator forces, it is observed that it can cause changes up to 25% in the maximum isolator displacements and maximum acceleration values. This differentiation is negligibly affected by how the seismic isolator is modeled. [ABSTRACT FROM AUTHOR]

Heat affects the mechanical properties of steel and the bearing capacity of steel structures, with joints being a crucial factor in determining their behavior. Steel can regain its mechanical properties that are lost owing to heat if the temperature remains below 600 °C, allowing for the possibility of reusing steel after cooling. In such cases, it becomes essential to assess the damage caused by heat exposure to decide whether to demolish the structure or continue using it. However, continuing its usage requires anticipating the potential negative effects of heat. To achieve this, it is necessary to determine the behavior of steel joining tools experimentally or numerically after exposure to heat. This study aims to ascertain the post-fire behavior of various end-plated beam and column connections, providing a cost-effective alternative to expensive fire experiments. Three different end-plated combination models were heated to a specified temperature, and steel frames were constructed after the elements cooled. Six three-point bending tests were conducted, and the experimental data obtained were validated using finite element models. The results indicate that the temperature causes a reduction in the bearing capacity of the joint, and the length of the end plate has a significant effect on the connection behavior. The finite element model validated by experiments is expected to facilitate numerical studies with different characteristics. [ABSTRACT FROM AUTHOR]

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On February 6, 2023, two major earthquakes (Mw 7.7 and Mw 7.6) occurred in the province of Kahramanmaraş in southern Türkiye at 9-h intervals, causing a lot of loss of life and destruction in the region where approximately 16% of the country's population lives. This study provides a comprehensive summary of common structural deficiencies that occurred in reinforced concrete (RC) buildings in earthquake-prone cities and proposes actionable measures systematically for future disasters. The evaluated data are based on the field observations of the authors. The main reasons for damages in RC buildings in the observation field can be classified into two categories: (1) the errors during the design stage (strong beam–weak column, short column, soft story, pounding effects, the existence of short and unconfined lap splices, insufficient transverse reinforcement, column–beam connection failures), and (2) the errors during the construction stage (poor concrete quality, unribbed reinforcing steel bar and corrosion, incorrect placement of reinforcement bars, incorrect end hook angle and length, weak gable walls, workmanship defects). Furthermore, a comparative nonlinear finite element analysis of the seismic impacts caused by the first earthquake on an existing RC building fully collapsed in the earthquake was conducted as a case study considering Türkiye Building Earthquake Code 2018 [TBEC 2018] "Türkiye Bina Deprem Yönetmeliği," Afet ve Acil Durum Yönetimi Başkanlığı, Ankara (in Turkish)]. The validity and accuracy of the reasons for damages, which were reached by the field observations, were also proven by numerical analysis results. The importance of complying with the regulations, conducting the performance evaluations and controls of the buildings according to the renewed earthquake regulations and, if necessary, repairing–strengthening works were emphasized. The loss of life and property after the earthquakes that we experienced on February 6, 2023, which were called the "Disaster of the Century", showed that Türkiye's current building stock, especially those built before a certain date, is insufficient against earthquakes. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to study semi-symmetric almost  α -cosymplectic three-manifolds. We present basic formulas for almost  α -cosymplectic manifolds. Using curvature properties, we obtain some necessary and sufficient conditions on semi-symmetric almost  α -cosymplectic three-manifolds. We obtain the main results under an additional condition. The paper concludes with two illustrative examples. [ABSTRACT FROM AUTHOR]