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Background The purpose of this study was to compare the effects of different distances between the end point of the osteotomy and the lateral cortex on the risk of lateral cortical fracture in the medial opening-wedge high tibial osteotomy (MOWHTO) procedure. Methods Eighteen synthetic tibia models were used. Saw cuts were performed on the test models (n=6 for all groups). Wedge gap distance and wedge opening load were evaluated using compression tests. Findings The mean maximum gap distance without a lateral cortical fracture was 19.90 mm in Group 5, 15.49 mm in Group 10, and 11.23 mm in Group 15. The differences between Group 5 and Group 10, Group 5 and Group 15, and Group 10 and Group 15 were statistically significant. The mean load just before the fracture was 13.24 N in Group 5, 18.31 N in Group 10, and 26.16 N in Group 15. The difference between Group 5 and Group 15 was statistically significant. No significant difference was observed between Group 10 and both Group 5 and Group 15. Interpretation As the end point of the osteotomy is brought gradually closer to the lateral cortex, wider gaps can be opened without a lateral cortical fracture. Thus, higher angle corrections can be achieved more safely by bringing the end point of the osteotomy closer to the lateral cortex, which should be preferred to reduce the risk of a lateral cortical hinge fracture during the MOWHTO procedure, from a clinical viewpoint. © 2022

Hardy and colleagues carried out “Renal autotransplantation” for the first time in 1963 to treat severe ureter injury and it has evolved as a method used for complex treatment of trauma, renal artery diseases or ureteral stenosis. In case of proximal ureter injury, ap-proximately 2/3 of which is iatrogenic, if the end-to-end anastomosis is not possible, renal autotransplantation, ileal ureter interposition or nephrectomy are alternative treatments. As technology advances, the use of ureterorenoscopy (URS) increases and in parallel with this iatrogenic injuries that occur during the process have increased as well. These types of injuries are generally in form of simple perforations (2–6%), but from time to time ureter avulsions are also observed (0.3%). In this article, a case is presented where renal autotransplantation is made following development of ureter avulsion during ureterorenoscopy process carried out due to right uret-eral calculi and treatment options are discussed in the light of literatures. © 2021 Turkish Association of Trauma and Emergency Surgery.

This study focuses on understanding of the sensitivities of the acoustophoretic process on uncertainties/errors in the geometric properties of the chip material and the piezoelectric actuators. The sensitivity of the acoustophoretic process is investigated both numerically and experimentally. For the numerical simulations a three dimensional finite element model is used. In the experimental analysis, a microfluidic chip with two stations is used. The first station has the accurate geometric values of the design and the second station has the introduced error in a geometric parameter so that the effect of this error can be demonstrated on the same chip and the channel., The Chemical and Biological Microsystems Society (CBMS)

Sloshing problems are highly non-linear problems and obtaining an accurate solution with numerical simulations is difficult and requires long simulation times. For this reason, sloshing experiments are important to understand the sloshing characteristics of liquid and to validate the theoretical and numerical studies in this field. In this study, an experimental setup which can input sine or random inputs to a sloshing system is designed and verified for different input amplitudes and frequencies. Then, the effect of vibration frequency and amplitude on the amplitudes of wave height and sloshing force are investigated. The effect of base motion frequency and the sloshing natural frequency on sloshing characteristics is also investigated. © JVE INTERNATIONAL LTD.

Experimental structural response of equipment mounted in store carried externally by jet type aircraft is investigated, predicted and compared with responses suggested by military standards in this study. A representative store which is similar to Mark-83 warhead with guidance units in terms of mass and geometry is used in this study. The main scope of this study is to evaluate the structural response proposed by military standards with real test conditions and also suggest a new method with an artificial neural network to predict the maximum response. Seventy-five different flight conditions are used to train the network for low and high frequency components. Also, eight flight conditions apart from the training set of flight conditions are used to test the approach. Acceleration levels are collected in real flight conditions by the data storage system. In signal processing, vibration response is expressed as power spectral density functions in the frequency domain. Procedures to predict the maximum response from measurements are determined with statistical limits in the literature. Besides the well-known limits in literature, third-order polynomial normal and logarithmic transform is used, and the performance of the different limits is compared. It is found that the military standard vibration spectrum is conservative. Distribution-free and normal tolerance limits predicted low frequency acceleration spectral density magnitudes more accurately. Their prediction performances were better than those of the other tolerance limits and that of the military standard. Third-order polynomial transform predictions are found to be reasonable with respect to normal prediction limit and envelope approach. Finally, it can be concluded that the response prediction method proposed in this article works well for Mark-83 warheads with guidance unit carried externally by jet fighter. © IMechE 2021.

In the present study, a 3D device-level numerical model is implemented via finite element method to assess the effects of design and operating parameters on the separation performance of a microscale acoustofluidic device. Elastodynamic equations together with electromechanical coupling at the piezoelectric actuators for the stress field within the solid parts, Helmholtz equation for the acoustic field within fluid, and Navier-Stokes equations for the fluid flow are coupled for the simulations. Once the zero-acoustic and flow fields are obtained, the trajectories of the particles are obtained by employing point-particle approach. The particle trajectories are simulated for many particles with different sizes released from random initial locations. Separation performances of the different cases are evaluated based on described metrics such as purity, yield, percentage of particle stuck in the channel, the force acting on the particles, residence time and separation parameter., This study is financially supported by the Turkish Scientific and Technical Research Council, under Grant No. 115M684. B.C. would like to acknowledge fundings from the Turkish Academy of Sciences through Outstanding Young Scientist Program (TuBA-GEBP) and Science Academy Distinguished Young Scientist Award (BAGEP)., Turkish Scientific and Technical Research CouncilTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [115M684]; Turkish Academy of Sciences through Outstanding Young Scientist Program (TuBA-GEBP); Turkish Academy of Sciences through Science Academy Distinguished Young Scientist Award (BAGEP)

This study focuses on understanding of the sensitivities of the acoustophoretic process on uncertainties/errors in the geometric properties of the chip material and the piezoelectric actuators. The sensitivity of the acoustophoretic process is investigated both numerically and experimentally. For the numerical simulations a three dimensional finite element model is used. In the experimental analysis, a microfluidic chip with two stations is used. The first station has the accurate geometric values of the design and the second station has the introduced error in a geometric parameter so that the effect of this error can be demonstrated on the same chip and the channel., The Chemical and Biological Microsystems Society (CBMS)

Experimental structural response of equipment mounted in store carried externally by jet type aircraft is investigated, predicted and compared with responses suggested by military standards in this study. A representative store which is similar to Mark-83 warhead with guidance units in terms of mass and geometry is used in this study. The main scope of this study is to evaluate the structural response proposed by military standards with real test conditions and also suggest a new method with an artificial neural network to predict the maximum response. Seventy-five different flight conditions are used to train the network for low and high frequency components. Also, eight flight conditions apart from the training set of flight conditions are used to test the approach. Acceleration levels are collected in real flight conditions by the data storage system. In signal processing, vibration response is expressed as power spectral density functions in the frequency domain. Procedures to predict the maximum response from measurements are determined with statistical limits in the literature. Besides the well-known limits in literature, third-order polynomial normal and logarithmic transform is used, and the performance of the different limits is compared. It is found that the military standard vibration spectrum is conservative. Distribution-free and normal tolerance limits predicted low frequency acceleration spectral density magnitudes more accurately. Their prediction performances were better than those of the other tolerance limits and that of the military standard. Third-order polynomial transform predictions are found to be reasonable with respect to normal prediction limit and envelope approach. Finally, it can be concluded that the response prediction method proposed in this article works well for Mark-83 warheads with guidance unit carried externally by jet fighter. © IMechE 2021.

In the present study, a 3D device-level numerical model is implemented via finite element method to assess the effects of design and operating parameters on the separation performance of a microscale acoustofluidic device. Elastodynamic equations together with electromechanical coupling at the piezoelectric actuators for the stress field within the solid parts, Helmholtz equation for the acoustic field within fluid, and Navier-Stokes equations for the fluid flow are coupled for the simulations. Once the zero-acoustic and flow fields are obtained, the trajectories of the particles are obtained by employing point-particle approach. The particle trajectories are simulated for many particles with different sizes released from random initial locations. Separation performances of the different cases are evaluated based on described metrics such as purity, yield, percentage of particle stuck in the channel, the force acting on the particles, residence time and separation parameter., This study is financially supported by the Turkish Scientific and Technical Research Council, under Grant No. 115M684. B.C. would like to acknowledge fundings from the Turkish Academy of Sciences through Outstanding Young Scientist Program (TuBA-GEBP) and Science Academy Distinguished Young Scientist Award (BAGEP)., Turkish Scientific and Technical Research CouncilTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [115M684]; Turkish Academy of Sciences through Outstanding Young Scientist Program (TuBA-GEBP); Turkish Academy of Sciences through Science Academy Distinguished Young Scientist Award (BAGEP)

Sloshing problems are highly non-linear problems and obtaining an accurate solution with numerical simulations is difficult and requires long simulation times. For this reason, sloshing experiments are important to understand the sloshing characteristics of liquid and to validate the theoretical and numerical studies in this field. In this study, an experimental setup which can input sine or random inputs to a sloshing system is designed and verified for different input amplitudes and frequencies. Then, the effect of vibration frequency and amplitude on the amplitudes of wave height and sloshing force are investigated. The effect of base motion frequency and the sloshing natural frequency on sloshing characteristics is also investigated. © JVE INTERNATIONAL LTD.