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Structure, mechanical, and neutron radiation shielding characteristics of mechanically milled nanostructured (100-x)Al-xGd2O3 metal composites
No full textFARKLI OBEZİTE FENOTİPLERİNDE YÜRÜYÜŞE AİT ZAMAN-MESAFE PARAMETRELERİNİN İNCELENMESİ
No full textAmaç: Çalışmanın amacı, android ve jinoid obezlerde yürüyüşün zaman-mesafe parametrelerinin sağlıklı bireylerden farkını araştırmaktır. Yöntem: Çalışmaya 18-65 yaş aralığında toplam 103 olgu katılmıştır. Vücut kütle indeksi (VKİ); normal (18,50-24,99 kg/m2) ve obez (≥30kg/m2) olguların bel/kalça oranları (BKO) tespit edilmiştir. Obezite fenotipi bel-kalça oranına göre belirlenmiştir. Android obez 43, jinoid obez 32 ve normal kilolu 28 olgunun dinamik pedobarografik analiziyle yürüyüşün zaman mesafe parametreleri değerlendirilerek karşılaştırılmıştır. Sonuçlar: Sallanma süresinin (sağ p=0,032, sol p=0,022), deselerasyon ivmesinin (sağ p=0,003; sol p=0,008) ve adım genişliğinin (bilateral p0,016). Adım genişliğinin android obezlerde normal kilolulara göre daha fazla olduğu bulunmuştur (p0,05). Tartışma: Çalışmamız her iki obezite fenotipinde adım genişliğinin normal bireylere göre arttığını, yalnızca jinoid obezlerde sallanma süresi ve deselarasyon ivmesinin azaldığını ve total vücut yağ oranın bunu etkilediğini göstermektedir. Sonuçlarımız obezitenin yürüyüşün zaman mesafe parametrelerini etkilediğini, ancak farklı obezite fenotiplerinin bu parametreler açısından benzer özelliklere sahip olduğunu ortaya koymuştur.</jats:p
A New Approach in Part Design for Friction Stir Welding of 3D-Printed Parts with Different Infill Ratios and Colors
No full textParts produced using a 3D printer are combined with friction stir welding (FSW). In the FSW processing of parts with a low infill ratio, welding errors occur due to a lack of material. In this study, plates were created using two different-colored PLA Plus filaments with different infill ratios in the weld area (20%, 60%, and 100%). Triangular pin geometry, different feed rates (20, 40, and 60 mm/min), and different tool rotation speeds (1250, 1750, and 2250 rpm) were used as FSW process parameters. Tensile testing was performed to determine weld strength and hardness measurements, and visual inspections were performed. Color measurements were made on the test samples before and after the welding process, and the relationship between welding performance and color was evaluated. The best welding strength was obtained as 17.83 ± 0.68 MPa at a feed rate of 20 mm/min, a tool rotation speed of 1750 rpm, and a part with a 60% infill ratio in the welding zone. In the sample with the best weld strength, the temperature was measured as 198.97 °C. Color changes in the weld area of parts with 60% and 100% infill ratios were measured between 78.9–82.2 and 79.1–84.5, respectively. It was determined that the color change decreases as the weld strength increases in these parts. The results show that with the proposed new part design, the FSW method can be used at low infill ratios, and the weld strength can be evaluated based on the color changes in the weld zone.</jats:p
Mechanical properties of elevator ropes and belts exposed to corrosion and elevated temperatures
No full textAbstract Safety in elevators is extremely important phenomenon. Elevator accidents occurring today are at a level that seriously threatens the safety of life and property, and especially elevator ropes and belts have a very important place in these systems in order not to endanger human life. As with every mechanism, stress, fatigue and deformations occur in elevator parts and equipments such as ropes and belts over time causing impairment and reduce their strength. In this study, artificial defects were given to the 8 × 19 Warrington steel wire rope and polyurethane coated elevator belt to examine the effects of different type of corrosion and elevated temperature deterioration on mechanical properties and their comparisons were made. Results indicate that the percent reduction in lifting capacity of the elevator belt investigated was lower than that of the 8 × 19 Warrington rope in all degradation types examined.</jats:p
Evaluation of the Risk of Malignant Arrhythmia Through Electrocardiography Parameters in Patients with Urinary Stone Disease
No full textIntroduction: With a lifetime frequency of 10-15% and a recurrence rate of up to 50% within 10 years, urinary stone disease is a major cause of comorbidity. Recently, it has become widely recognized that urinary system stone disease is not only limited to kidney stone development but is also linked to cardiovascular disease and various other illnesses. Malignant arrhythmias (sudden cardiac death and ventricular arrhythmias) are consequences of coronary artery disease. Despite numerous studies demonstrating that urinary system stone disease is a risk factor for coronary artery disease, no electrocardiographic parameters have been evaluated in this patient group This prospective observational study aims to assess ventricular repolarization parameters using electrocardiography, which are risk indicators for malignant arrhythmias in patients with urinary stones disease. Materials and Methods The study included patients diagnosed with urinary stone disease and healthy volunteers. All patients underwent 12-lead electrocardiography. The electrocardiographys were evaluated for QTc interval, QTc dispersion, T peak-end interval, and Tp-e/QTc, and compared with the control group. Results: When comparing the QTc interval, QTc dispersion, T peak-end interval, and Tp-e/QTc parameters between the patient and control groups, no statistically significant differences were found. Conclusion: Contrary to existing knowledge, this study found that malignant arrhythmias in patients with urinary stone disease were not significantly different from the normal population.</jats:p
Investigation of the Mesiodistal Angulations of Maxillary Canines and Central Incisors for Missing Bilateral Maxillary Lateral Incisor
No full text(1) Background: A missing bilateral maxillary lateral incisor (MBMLI) causes aesthetic and functional problems and a multidisciplinary approach is required for treatment. This study aimed to compare the changes in the mesiodistal axial angulations of the maxillary canines and central incisors with orthodontic treatment of MBMLI. (2) Methods: A total of 56 patients with MBMLI were included in the study, and three groups were formed: the control group (Group 1, n = 20) with untreated ideal occlusion and the space opening (Group 2, n = 20) and space closure (Group 3, n = 16) groups as treated study groups. The mesiodistal angulations between the long axes of the maxillary right canine (tooth no 13), right central incisor (tooth no 11), left central incisor (tooth no 21) and maxillary left canine (tooth no 23), and the bicondylar plane, were measured on the panoramic radiographs taken pre (T0) and post treatment (T1). p < 0.05 was accepted for statistical significance. (3) Results: At T0, while there was no significant difference between the mesiodistal angulations of the right–left maxillary canines and central incisors in all groups (p > 0.05), the mesiodistal angulations of the canines in the Group 1 were significantly higher than the study groups (p < 0.05). With treatment, while the mesiodistal angulation of the canines increased in Group 2, it decreased in Group 3 (p < 0.05). On the other hand, the mesiodistal angulation of the central incisors decreased in Group 2 and did not change in Group 3 (p > 0.05). At T1, the mesiodistal angulation of the canines was found to be lower in Group 3 than in Groups 1 and 2, while the angulation of the central incisors was found to be lower in Group 2 compared to Group 1 (p < 0.05). (4) Conclusions: In the orthodontic treatment of MBMLIs, changes in the mesiodistal angulations of the maxillary canine and central incisors should be taken into account for satisfactory outcomes. It was concluded that there should be a tendency to select the space closure method in which normal mesiodistal angulations are obtained in maxillary central incisors for aesthetics and planned incisor position, and also at a low cost.</jats:p
Unveiling the Phenolic Compounds of Chestnut Honey-Based Propolis and in Silico Phytoestrogen Activity
No full textAn experimental and computational studies, evaluating the in vitro antidiabetic and antioxidant activity, in silico prediction ADMET properties of 5‐chloro‐1H‐benzimidazole and its newly synthesized silver(I) complex
No full textIn this research, a new Ag(I) complex, namely, [Ag(5‐chloro‐1H‐benzimidazole)2(NO3)], has been synthesized using the benzimidazole‐based ligand 5‐chloro‐1H‐benzimidazole (5ClBZ). Ag(I) complexes were characterized by elemental analysis, UV‐Vis, FT‐IR, and1H NMR spectroscopy, and DFT analysis was used. The free ligand and its Ag(I) complexes were tried for their biochemical properties, including antioxidant and antidiabetic properties. To study the molecular structures of the title compounds, in silico ADME/Tox research was performed on the newly made complex and free ligand. The empirical guidelines relating to ADME were utilized to conduct molecular docking simulations and in‐depth drug‐likeness profiling. This was carried out to validate the conclusions and identify exact binding interactions. Based on the study's findings, it has been determined that these new compounds have significant potential as powerful therapeutic agents for controlling antioxidant and antidiabetic activities.</jats:p
Radiosensitivity in a newborn with microcephaly: A case report of Nijmegen breakage syndrome
No full textAbstractAimNijmegen breakage syndrome (NBS) is an autosomal recessive DNA repair disorder which is characterized by immunodeficiency and increased risk of lymphoproliferative malignancy.CaseWe observed an increase in the rate of chromosomal rearrangements in the cultured cells following an incidental radiograph for craniosynostosis in a newborn who was followed up due to microcephaly. We identified a homozygous deletion of c.657_661delACAAA/p.Lys219fs (rs587776650) in the NBN gene through whole exome sequencing.ConclusionIt is crucial to thoroughly examine the clinical features of newborns with microcephaly and consider chromosomal instability syndromes just like Nijmegen breakage syndrome. Not overlooking radiosensitivity, which is a characteristic feature of this syndrome, is a vital condition to the patient's survival time.</jats:sec