Advantages of Compound S-scan over Sectorial Scan or E-scan: A Case Study

Within PAUT, inspectors have the option to apply various scanning techniques for performing weld inspections according to their configurations. These include the sectorial scan (S-scan) or a fixed-angle electronic scan (E-scan), or a combination of both called a compound S-scan. Compound S-scan, introduced around 2015 (Magruder 2016), has not been much explored, as not enough data can be extracted from the available resources to determine its effectiveness for inspection. Therefore, the author has taken a specific interest in studying this technique by comparing the available PAUT scanning techniques and providing options for selecting the most appropriate scanning techniques for the intended applications. For this purpose, a 25 mm thick welder qualification test plate with natural defects (verified by RT) was studied.

Recent Methods of Neck Femur Fixation A Systematic review and meta-analysis

Background Femoral neck fractures in adults younger than age 50 years are uncommon and often the result of high energy trauma. They account for only 2-3% of all femoral neck fractures. Femoral neck fractures are associated with aging and osteoporosis and can occur after relatively trivial trauma in elderly patients. femoral neck fractures are associated with higher incidences of femoral head osteonecrosis and nonunion. Fixation options include cannulated screws, non parallel cannulated screws, medial augmentation plate, and fixed angle femoral neck fixation implants. A systematic review of literature done to evaluate which technique is better. Methods After literature search thirteen articles were found and were reviewed to evaluate final outcome of fixation of neck femur fractures by cannulated screws, non parallel cannulated screws, medial augmentation plate, and fixed angle femoral neck fixation implants. Results After evaluation of all studies the incidence of nonunion, osteonecrosis of femoral head, implant failure & revesion surgery is lower in comparing Targon plate with multiple cannulated screws while we need further studies for application of non parallel screws and medial plate. Conclusion Targon plate recorded low incidence of complications in the final outcome in comparison with multiple cannulated screw while we need further studies for application of Non parallel screws and medial plate.

Assessment and Management of Acute Volar Rim Fractures

The volar rim of the distal radius is the only bony restraint to volar carpal subluxation. Higher loads across the volar rim require stable and rigid fixation to maintain reduction and allow healing while rehabilitation begins. Volar marginal fragments are not amenable to buttressing by fixed angle volar locking plates. Appropriate management of volar marginal fragments comprises two steps—recognition of their presence and rigid anatomical repair. The best opportunity for success in the presence of a volar marginal fragment is its adequate initial treatment. The purpose of this review is to reinforce the importance of a complete preoperative and intraoperative evaluation of distal radius fractures. Volar marginal fragments can easily be overlooked even following initial reduction and fixation. Understanding the relevant anatomy and loading parameters can facilitate intraoperative decisions on approach and fixation, which are integral to achieving optimal clinical outcomes.

The Fixed Angle Scattering Problem with a First-Order Perturbation

We study the inverse scattering problem of determining a magnetic field and electric potential from scattering measurements corresponding to finitely many plane waves. The main result shows that the coefficients are uniquely determined by 2n measurements up to a natural gauge. We also show that one can recover the full first-order term for a related equation having no gauge invariance, and that it is possible to reduce the number of measurements if the coefficients have certain symmetries. This work extends the fixed angle scattering results of Rakesh and Salo (SIAM J Math Anal 52(6):5467–5499, 2020) and (Inverse Probl 36(3):035005, 2020) to Hamiltonians with first-order perturbations, and it is based on wave equation methods and Carleman estimates.

Fixed angle inverse scattering in the presence of a Riemannian metric

We consider a fixed angle inverse scattering problem in the presence of a known Riemannian metric. First, assuming a no caustics condition, we study the direct problem by utilizing the progressing wave expansion. Under a symmetry assumption on the metric, we obtain uniqueness and stability results in the inverse scattering problem for a potential with data generated by two incident waves from opposite directions. Further, similar results are given using one measurement provided the potential also satisfies a symmetry assumption. This work extends the results of [Rakesh and M. Salo, Fixed angle inverse scattering for almost symmetric or controlled perturbations, SIAM J. Math. Anal. 52 2020, 6, 5467–5499] and [Rakesh and M. Salo, The fixed angle scattering problem and wave equation inverse problems with two measurements, Inverse Problems 36 2020, 3, Article ID 035005] from the Euclidean case to certain Riemannian metrics.