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As the effect of many medical agents such as nonsteroidal anti-inflammatory drugs or antibiotics were investigated on bone fracture healing, there is no study about the anesthetic agents when compared histopathologically and biomechanically. We asked the question that if a superiority can be between them since we operate many fractures and see the delayed or nonunions. Although different anesthetic agents are used in general anesthesia, the effects of these substances on bone fracture healing are not clear. Here, we intended to research different anesthetic agents on fracture union in rats. The study was done between January 2020 and November 2021 in a university animal research laboratory. Totally 48 male Wistar-Albino rats weighing 250–300 g were seperated into 3 groups as Tiyopental Na in Group 1, Ketamin in Group 2 and Propofol in Group 3. For anesthesia; 40, 100, 100 mg/kg of single dosages were injected intraperitoneally, respectively. A shaft fracture was created bilaterally to the tibia of all rats. Kirschner (K) wire is used for the fixation of fractures. Biomechanical and histopathological examination in bones is performed at the end of the first and second months in terms of fracture healing. It has been found that the fracture union in group 1 was statistically signifigant higher than group 3 at the end of the first and second months histopathologically (P = 0.006, P = 0.002). It is also found there is a statistically significant difference between groups 1 and 3 after the second month biomechanically (P = 0.013). Although the union was higher in group 1 than group 2 histopathologically and biomechanically after the first and second months, there was no statistically significant difference (P = 0.376, 0.039; P = 0.028, 0.867). There was a general trend in the decrease of union measurements starting from group 1 to 3 at the end of the first and second month both histopathologically and biomechanically. In this study, it is found that there was a positive consistency between histopathological and biomechanical results with respect to bone union. They supported each other. Fracture healing is stronger in rats that were anesthetized by using thiopental than those using ketamine and propofol, we think that this may affect the choice of anesthetic agent and further studies are needed. [ABSTRACT FROM AUTHOR]

The investigation mentioned focuses on utilizing finite element analysis to study the impact of anisotropy parameters on the behavior of earrings during the deep drawing process. deep drawing is a manufacturing technique used to transform flat sheet metal into three-dimensional shapes, and anisotropy refers to the directional dependence of material properties. by analyzing and understanding how anisotropy parameters affect the behavior of earrings during the deep drawing process, this investigation aims to provide valuable insights for optimizing the manufacturing process and enhancing the quality and durability of earrings. In this study, an Al6061-T6 sheet material with different planar anisotropies with a single thickness of 2 mm was employed to simulate the effects of anisotropy parameters on the earring by using finite element method. The effects of anisotropy parameters on the earring were examined by using FEM. Variations force obtained in Δr2 are higher than Δr1. This is due to the anisotropy of the material. It can be said that the FEM simulations give reasonable results in view of earring for deep drawing processes. So, experimental costs can therefore be avoided using a suitable FEM model. [ABSTRACT FROM AUTHOR]

The nitriding process is a surface treatment that improves the surface properties of titanium alloys and increases wear/corrosion resistance. This study investigates the structural and mechanical property changes in titanium alloy after nitriding. Micro-hardness differences between the nitrided and non-nitrided surface and morphological changes on the surface were determined. In addition to evaluating the effect of vanadium and aluminum ions on the nonnitrided surface, the impact of nitrided and non-nitrided surfaces on biofilm layer formation was investigated. It was determined that the TiN layer formed on the nitrided surface showed superior properties to its non-nitrided surface in the biofilm tests performed for 6 h. As a result of the tensile tests, it can be said that the nitriding process increases the elasticity module of the Ti–6Al–4V alloy and provides the material to have a more rigid structure. It was also analyzed using finite element analysis (FEA) of mechanical behaviors of the test sample under the tension loads. [ABSTRACT FROM AUTHOR]

Carrying out an engineering process with the least cost and within the shortest time is the basic purpose in many fields of industry. In Computer Numerical Control (CNC) machining, performing a process by following a certain order reduces cost and time of the process. In the literature, there are research works involving varying methods that aim to minimize the length of the CNC machine tool path. In this study, the trajectory that the CNC machine tool follows while drilling holes on a plate was discussed within the Travelling Salesman Problem (TSP). Genetic Algorithms (GA), Particle Swarm Optimization (PSO), and Grey Wolf Optimizer (GWO) methods were used to solve TSP. The case that the shortest tool path was obtained was determined by changing population size parameter in GA, PSO, and GWO methods. The results were presented in tables. [ABSTRACT FROM AUTHOR]

In bone-drilling operations, undesirable temperature rises are experienced due to high-contact friction. These increases in temperature can damage bone and soft tissues from time to time. When the temperature exceeds 47∘C, osteonecrosis occurs. This article presents a new method for both the selection of optimum drilling parameters and the mathematical temperature model (T ∘C). In this study, the optimum parameter values for bone-drilling operations were found using gray relational analysis, and a mathematical model was created based on the temperature parameters using the response surface method. The accuracy of the developed analytical model has been proven by ANOVA. As a result, it has been revealed that the value of spindle speed is the most effective factor in bone-drilling operations and that the developed analytical model and experimental measurements are in harmony. [ABSTRACT FROM AUTHOR]

Several fractures that occur in the human body depend on trauma or as a result of hormonal and bone fatigue. Fracture types that take place out of the neck area of the femoral bone are named femoral shaft fractures. Femoral shaft fractures are frequent conditions in orthopedics. Conventional plating method is a method that necessitates the fixation of the contact surface by contacting the epiphyses used in the treatment of such fractures. This method is known to be efficent in speeding up the healing process by reducing the movement between the epiphyses. In this study, femur models which are plated in various forms with fractures were analyzed with computer-aided finite element software and stresses on bone surfaces and fracture surfaces were determined. It is aimed to determine the best result by examining the relationship between the inputs such as the number of screws used during plating, the fixation area and material selection and the outputs obtained by finding the stresses on the bone surface and stresses on the broken surfaces. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this study was to compare side-to-side and functional end-to-end anastomosis techniques that are commonly used in bowel surgery. Considering the dimensions of these two different anastomosis models, SolidWorks program was used for 3 D studies. Intra-intestinal flow analyzes were performed based on the finite volume method using Ansys Fluent, a computational fluid Dynamics (CFD) program. The flow velocity, pressure, turbulent knetic energy, turbulence vortex distribution, vortex viscosity and wall shear stresses for each model were calculated in results of the analysis for the side-to-side and functional end-to-end anastomosis technique. Due to the geometrical structure of the functional end - to - end anastomosis model, turbulence and hence the vortex formation is less than the side - to - side anastomosis technique. Because intersect area of bowels has wider in functional end - to - end anastomosis model, flow become easier than other. In surgical practice, functional end-to-end anastomosis is preferred over side-to-side anastomosis because of the low probability of leakage. It can be noted that the functional end - to - end anastomosis technique will be safer because of less turbulence, based on the data of fluid flow velocities, pressure, turbulent knetic energy, turbulence vortex distribution, vortex viscosity and wall shear stresses in the anastomosis. [ABSTRACT FROM AUTHOR]

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Friction drilling processes are used commonly in hot forming operations. This process is similar to drilling processes but without using chip. This process is used especially for joining thin-walled metal components. In this study, the drilling process using centerdrill is investigated both experimentally and numerically. The finite element analyses (FEA) were conducted using deform-3D software based on finite element method (FEM). In this study, an analytic model is developed, which calculate the process parameters as torque and axial power, heat transfer coefficient. A comparison was also made for temperature, torque and axial force obtained from experimental and numerical analyses. At the end of the study, while the torque and axial force values decrease with increasing of spindle speed, temperature values of centerdrill and workpiece increase with increasing of spindle speed. A good consistency between both experimental and FEA simulations was found during the centerdrill process. [ABSTRACT FROM AUTHOR]

The deflections appeared by cutting forces in ball end milling of inclined surfaces can result in defects in workpiece. Finding deflection values has a significant importance for keeping the production within the appropriate tolerances and in lessening production costs. The aim of this study was to evaluate tool deflection values experimentally, analytically, and numerically depending on cutting force in ball end milling of inclined convex and concave surfaces of DIN 1.2344 using TiN-coated cutting tool. The experiments were conducted with different cutting tools strategies and cutting parameters at related parameter levels. During machining, real time cutting tool deflections were recorded by inductive sensors for the experiments. In analytical studies, tool deflections were calculated depending on cutting force using cantilever beam method. In numerical studies, the solution was made with the finite element method. In the implementation of this method, commercial finite element software ANSYS was used. As a result, the values of tool deflections measured experimentally were found to match closely with analytical and numerical studies. The most effective parameters within the selected cutting parameters for both inclined surfaces were found step over and feed rate. At the same time, the measurement of dynamic deflection with inductive sensors was found to be beneficial for three-axis milling operations. [ABSTRACT FROM AUTHOR]

It is known that diabetes mellitus has late complications, including microvascular and macrovascular diseases. Diabetes can affect bones through biochemical markers of bone structure, density, and turnover. This study aimed to biomechanically investigate the bone-protective effects of angiotensin 1-7 (Ang 1-7), one of the active peptides in the renin-angiotensin system, in rats with diabetes. Thirty male Wistar albino rats, three months old and weighing 250-300 g, were divided into four groups: diabetes, Ang 1-7, diabetes plus Ang 1-7, and control. One month later, diabetes developed in rats; the rats were sacrificed, and their right femur was removed. Three-point bending biomechanical tests were performed on the femurs. The diabetic group had significantly higher bone fragility than the other groups (Pr >.05). Bone fragility was lower, and bone flexibility was higher in the Ang 1-7 groups (Pr>F value 0.05). As a result of our study, the effect of Ang 1-7 on the bones of rats with diabetes was investigated biomechanically. Ang 1-7 has a protective impact on the bones of rats with diabetes. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the process of friction stir welding (FSW) by using finite element method (FEM). Currently, the materials that are difficult to be joined with conventional fusion methods can now be easily joined with the method of friction stir welding. In this paper, the welding capability of many different materials with this method has been investigated by using analytical and numeric methods. In this study, a finite element (FE) model was developed for welding process with friction stir welding of AZ31 magnesium alloy. This model was performed by the software of DEFORM 3D finite element in 960, 1,964, and 2,880 rpm rotational speeds and in 10 and 20 mm min transverse speeds. The temperature values taken from experiments and the temperature values with FEM are compared, and according to these results, it can be stated that the FE model gives reasonable results with experimental results based on temperatures values. Hence, the FE model can be used to predict other parameters of FSW process in future studies. [ABSTRACT FROM AUTHOR]

Copyright of Teknoloji is the property of Engineering Science & Technology, an International Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The re-adaptation process that the brain exhibits as a response to the environmental modifications resulting from prolonged or sudden limb loss can be described as a part of brain plasticity. In some cases, due to neurons synaptic interaction with neighboring neurons, motor-sensory representation of a hand can be replaced. In this study, it is aimed to develop neurophysiologic approaches for identification and discovery of structural and functional, transient and permanent plastic changes in arm-transplant cases. Abductor Pollicis Brevis (APB) and Orbicularis Oris (O. Oris) muscle representation mapping are performed using Transcranial Magnetic Stimulation (TMS) for a double-arm transplant. A control group is established to interpret the cortex map of the transplantation case. The position, amplitude, and latency values of the motor evoked potentials, which are generated by a magnetic stimulation, are determined by the developed software. Results are embedded on the designed 3D head model and the TMS map is created. Depending on results of the mapping, hotspot of the control group is found as C1(6.89( ± 1.67) mV–20.98( ± 0.87) ms) in the 10–10 system and hotspot of the hand mapping is C3(1 mV–38.9 ms). 85.48% decreases in amplitude and 85.41% increases in latency value occur in the hand mapping with respect to the control group. As a result of the comparison of the generated maps with the normal group, brain plastic change is observed in the double-arm transplant. Although the transplantation period of 1 year is yet to be completed, the brain adaptation is still proceeding. In this case, the hand representing area has spread towards the face representation area. This study is supported by TUBITAK with 215E012 project number. [ABSTRACT FROM AUTHOR]

Facial transplantation is defined as transfer of facial tissue from a donor to a patient who has suffered facial loss as a result of total denervation. Loss of facial tissue in the patient’s transplant history is important for synaptic change. Our study aims to develop neurophysiological approaches by defining the change of motor representations in the brain. In this study, Transcranial Magnetic Stimulation (TMS) is used to create Orbicularis Oris (O.Oris) and Abductor Pollicis Brevis (APB) muscles representation maps in facial transplant cases. Control group is established to identify brain presentation changes in facial transplant cases. The position, amplitude and latency values of muscular action potentials induced by magnetic stimulation are determined by signal processing methods. The results are mapped on 3-D human model. In the first case, the hot spot is identified as FC5 (4.66 mV to 5 ms) in the face mapping. When the face mapping of the patient is compared with the control group, the hot spot amplitude value is acquired as 64.25% and the latency value is 1.01% higher. In this case, the facial responses become more lateral. In the second case, the hot spot is found as AF7 (1.41 mV to 5.40 ms), and 50.29% decreases in amplitude value and 9.09% increases in latency value occur in the face mapping. It is observed that the facial responses are enlarged anteriorly and hand responses are detected in the face area. The results which denote the existence of the brain plasticity in the face transplant patients can be evaluated in the planning of rehabilitation processes. This study is supported by TUBITAK with 215E012 project number. [ABSTRACT FROM AUTHOR]

In this paper, an experimental investigation on tool wear, cutting forces and surface roughness in machining of Austempered Ductile Iron (ADI) using cemented carbide inserts is presented. Ductile iron (DI) specimens were first austenitized in salt bath at 900 °C for 60 min. after which they were quenched in salt bath at 250°C ve 325°C for 60min. The cutting forces were measured using a three-component Kistler dynamometer. The turning tests were conducted with variable cutting speeds ranging from 75 to 250 m/min. under constant depth of cut and feed rate. The results indicate that the lower austempering temperature results in higher cutting forces and better surface roughness. The tool wear occurs mainly at the tool flank. Tool life decreases with decreasing austempering temperatures. Besides decreasing austempering temperature results in increased tool wear as well. [ABSTRACT FROM AUTHOR]