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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]

Purpose: To investigate the association of prephotorefractive keratectomy Schirmer-1 test value with postphotorefractive keratectomy central corneal epithelial thickness, ocular surface disease index score, and uncorrected distance visual acuity. Methods: Patients were categorized according to preoperative Schirmer-1 value: the normal Schirmer Group (n=54; Schirmer-1 test value, >10 mm) and the low Schirmer Group (n=52; Schirmer-1 test value, between 6 and 10 mm). We analyzed ablation depth, visual acuity, result of Schirmer-1 test (with anesthesia), tear film break-up time, ocular surface disease index score, central corneal epithelial thickness, and spherical equivalent refraction. Results: We found significant differences between the groups in Schirmer-1 test value, tear film break-up time, and ocular surface disease index score, both preoperatively and postoperatively (p<0.001). The preoperative central corneal epithelial thicknesses of the two groups were similar (p>0.05). After photorefractive keratectomy, the Schirmer-1 test value and spherical equivalent refraction decreased in both groups (p<0.05), and ocular surface disease index scores and central corneal epithelial thickness values increased in the low Schirmer Group (p<0.001) but not in the normal Schirmer Group (p>0.05). The postoperative central corneal epithelial thicknesses of the low Schirmer Group were significantly higher than those of the normal Schirmer Group (p<0.001). Postoperative uncorrected distance visual acuity did not differ significantly between the two groups (p>0.05). Conclusions: In patients with low Schirmer-1 test values before photorefractive keratectomy, the corneal epithelium thickened and ocular surface complaints increased during the postoperative period. However, changes in the corneal epithelium did not affect the postoperative uncorrected distance visual acuity. To reduce postoperative problems on the ocular surface in these patients, we recommend that dry eye be treated before photorefractive keratectomy. [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]

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]

Purpose: To our knowledge, no study has so far assessed in detail the relationships between subconjunctival hemorrhage (SCH) sites and SCH causes in patients with non-traumatic SCH (NTSCH). Therefore, in this study, we aimed to investigate comprehensively these relationships. Methods: Four-hundred nineteen cases were included. SCH sites were classified as superior (n = 109), nasal (n = 114), temporal (n = 84), and inferior (n = 112) areas. Etiological factors associated with NTSCH were determined as hypertension, diabetes mellitus, coagulation system disorders, conditions causing sudden venous congestion (CCSVC), and idiopathy. Relationships between SCH sites and causes were analyzed. In addition, evaluations were made according to age (=60 and >60 years). Results: In cases aged =60 years, nasal site hemorrhage was more frequent than temporal (35.0% vs. 21.7%, P = 0.016) and inferior (35.0% vs. 15.2%, P < 0.001) site hemorrhages. In individuals aged >60 years, inferior site hemorrhage was more frequent than superior (39.1% vs. 23.8%, P = 0.012), nasal (39.1% vs. 18.8%, P < 0.001), and temporal (39.1% vs. 18.3%, P < 0.001) site hemorrhages. In cases aged =60 years, etiological factors were seen with similar frequency in superior, temporal, and inferior site involvements (P > 0.05), while hemorrhage in nasal site was most frequently associated with CCSVC (46.1%, P < 0.01). In individuals aged >60 years, etiological factors were observed with similar frequency in superior, nasal, and temporal site involvements (P > 0.05), while hemorrhage in inferior site was most frequently associated with hypertension (48.1%, P < 0.02). Conclusion: We determined that nasal NTSCH was most frequently associated with CCSVC in cases aged =60 years, while inferior NTSCH was most frequently associated with hypertension in individuals aged >60 years. [ABSTRACT FROM AUTHOR]

This article aims to study almost α -Kenmotsu pseudo-Riemannian structure. We first focus on the concept of almost α -Kenmotsu pseudo-Riemannian structure and its basic properties. Then, we shall prove some fundamental formulas and some classification results on such manifolds with CR-integrable structure. Finally, some illustrative examples of almost α -Kenmotsu pseudo-Riemannian manifold are given. [ABSTRACT FROM AUTHOR]

Background. Catatonia is a complex neuropsychiatric disorder involving stupor, waxy flexibility, and mutism lasting more than 1 hour. It has arisen mostly from mental and neurologic disorders. Organic causes are more prominent in children. Case. A 15-year-old female who had refused to eat and drink for 3 days, had not talked, and had stood in a fixed position for long periods was admitted to the inpatient clinic, and she was diagnosed with catatonia. Her maximum score on the Bush-Francis Catatonia Rating Scale (BFCRS) was 15/69 on day 2 of her stay. On neurologic examination, the patient's cooperation was limited, and she was apathetic to her surroundings and stimuli and inactive. Other neurologic examination findings were normal. To investigate catatonia etiology, her biochemical parameters, thyroid hormone panel, and toxicology screening were conducted but all parameters were normal. Cerebrospinal fluid examination and autoimmune antibodies were negative. Sleep electroencephalography showed diffuse slow background activity, and brain magnetic resonance imaging was normal. As a first-line treatment for catatonia, diazepam was started. With her poor response to diazepam, we continued to evaluate the cause and found the transglutaminase levels were 153 U/mL (normal values, <10 U/mL). The patient's duodenal biopsies showed changes consistent with Celiac disease (CD). Catatonic symptoms did not benefit from a gluten-free diet or oral diazepam for 3 weeks. Then, diazepam was replaced with amantadine. With amantadine, the patient recovered within 48 hours, and her BFCRS retreated to 8/69. Conclusions. Even without gastrointestinal manifestations, CD may present with neuropsychiatric symptoms. According to this case report, CD should be investigated in patients with unexplained catatonia, and that CD may only present with neuropsychiatric symptoms. [ABSTRACT FROM AUTHOR]

Numerical solution of the transport equation for monoenergetic neutrons scattered isotropically through the medium of a finite homogeneous slab is studied for the determination of the eigenvalues. After obtaining the discrete ordinates form of the transport equation, separated homogeneous and particular solutions are formed and then the eigenvalues are calculated using the Gauss-Legendre quadrature set. Then, the calculated eigenvalues for various values of the c0, the mean number of secondary neutrons per collision, are given in the tables.

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Aim: To determine the effects of face mask usage on ocular structures in children during the coronavirus disease-2019 (COVID-19) pandemic Materials and Methods: Forty-two children's ocular data from the pandemic period were compared with the same children's ocular data from the pre-pandemic period. Results: Their mean age was 14.6±2.1 (9-18) years initially. The tear film break-up time values of the children with a mask in the pandemic period were significantly shorter than those of the children without a mask in the pre-pandemic period (9.35±1.40 vs. 12.10±1.05 seconds, p=0.033). There was no staining in any case in the pre-pandemic period, while minimal punctate epithelial corneal staining pattern was determined in 4 (9.5%) children in the pandemic period. The Schirmer test 1 value detected in the pandemic period was similar to the value detected in the pre-pandemic period (11.14±2.07 vs. 12.03±1.01 mm, p=0.127). Additionally, there were no significant changes in visual acuities, central corneal thicknesses, anterior chamber depths, lens thicknesses, and axial lengths between the pre-pandemic and pandemic periods (p>0.05). Conclusion: To the best of our knowledge, this is the first study to date to evaluate the effects of face mask usage on ocular structures in just children. The use of face masks may cause increased tear evaporation and dry eye in pediatric cases. Educating children about the correct use of face masks can be important. Thus, possible ocular surface changes which may occur relating to masks can be prevented, and children may be more willing to use masks. Increased mask compliance may also indirectly help protect children from the virus. [ABSTRACT FROM AUTHOR]