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Purpose: To determine whether synthetic grafts are a satisfactory treatment option for pathological proximal femoral fractures in children. Methods: Paediatric patients treated for pathological fractures of the proximal femur between 2013 and 2020 were evaluated retrospectively. 17 patients with a mean age of 10.7 years (range 6–16 years) were assessed. The definitive histopathological diagnoses were SBC (simple bone cyst) (12) and ABC (aneurysmal bone cyst) (5). The median duration of follow-up was 37 months (range 12–70 months). Results: All patients returned to their normal daily routine within 3–8 months following surgery. The mean post-op recovery time was 3.2 months (range 3–6 months). Graft was incorporated at approximately 12 months. No significant radiographic healing was observed in 2 patients. In the remaining 15 patients, the mean duration of healing was 14 months (range 8–24 months). Conclusion: Synthetic grafts are a satisfactory treatment option for pathological proximal femoral fractures in children. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the cluster consensus problem for inherently nonlinear cooperative networks with first and second‐order system dynamics. For a first order multi‐agent network evolving over a directed graph, not necessarily containing a spanning tree, a sufficient condition based on Lyapunov theory is derived on the single controller parameter so that the system achieves cluster consensus. These stability results are extended to second‐order nonlinear systems that utilize two parameters in the distributed control law. Furthermore, the total number of clusters and members of each cluster are explicitly computed from the primary and secondary layer subgraphs of the underlying directed graph. The results are the first in the literature to address the cluster consensus problem for inherently nonlinear cooperative networks evolving over directed graphs that do not contain a spanning tree. [ABSTRACT FROM AUTHOR]

Energy resources are decreasing in the world and the use of electrical machines is increasing. Motor design and development studies are carried out to reduce the losses and increase the efficiency of motors, which are widely used especially in industry. In this study, Line Start Synchronous Reluctance Motor (LS-SynRM) was designed by taking an induction motor, one of the most widely used motors in the industrial field, as a reference. With its rotor cage structure feature, it can be line-start without the need of a driver. The rotor has a lot of design variables due to slots and barriers. Sensitivity analysis was used to determine the effect of design variables on performance criteria such as power factor, efficiency and torque ripple. Subsequently, Multi-Objective Genetic Algorithm (MOGA) optimization was used to find the values of the design variables that bring the motor performance closer to the optimum result. The results of the reference induction motor, initial LS-SynRM, and the optimized LS-SynRM are compared. It has been taken care to preserve the synchronization feature of the LS-SynRM and the related results are given in the analyses. It is shown that the optimized motor is in IE4 efficiency class and operates with low torque ripple. [ABSTRACT FROM AUTHOR]

Axial flux induction motors (AFIM) are gaining popularity due to their higher torque density than radial flux motors. However, axial flux motors have a more complex structure than radial flux motors due to their diameters expanding from the inside out. Before manufacturing, designers have two contradictory goals in the simulation phase. These are high accuracy and short analyses time. The finite element method is a commonly utilized technique for verifying designs. However, in the early stages of AFIM design, a 2D radial flux modeling approach can yield faster results. This approach is well-suited for radial motors, where 2D analysis is widely employed to achieve accurate designs within reasonable analysis times. However, for AFIM with a non-axisymmetric flux path, the application of 2D analysis poses some difficulties. This study compares three modeling approaches, linear, inner rotor and outer rotor modeling approaches to a 3D model and examines their steady-state performance. The results show compatibility in performance data, with some deviations in the torque-speed curve for inner rotor modeling and outer rotor modeling approach methods, which can be reduced by resizing the slots. Overall, acceptable errors and consistent results were achieved between the models. [ABSTRACT FROM AUTHOR]

Aim: To determine the prevalence of developmental dysplasia of the hip (DDH), a common condition in our region, and investigate the underlying factors contributing to its occurrence. Methods: A total of 715 hips from 370 newborns were evaluated using ultrasonography. The patients' gender, alpha, and beta angles, affected hip, and Graf classification types were noted. Risk factors were compared between the groups. Patients diagnosed with DDH were treated with the Pavlik harness. Results: In the initial evaluation, 61 out of 370 patients (16%) were diagnosed with Graf type 2c, 3, or 4 hips. 48 patients were female, and 13 patients were male. Patients who were female (20.1%) had a statistically significant greater incidence of DDH than patients who were male (9.8%) (p<0.05). In terms of statistical significance, there was no difference between DDH incidence in the right hip and left hip (p>0.05). The application of swaddling was more frequent in the group with diagnosed DDH compared to the normal group (p<0,05). Pavlik treatment was applied to 41 hips. After the treatment, 30 hips converted to type 1 hips. Six hips remained as type 2b, three hips progressed to type 2c, and one hip progressed to type 3. Conclusions: DDH continues to be a widespread concern. The incidence in our region is higher compared to other areas. Enhancing screening initiatives, pinpointing key risk factors, and bolstering family education are imperative steps towards its prevention. [ABSTRACT FROM AUTHOR]