This study described a preparation procedure for BSA NPs with controllable particle size, and such polymer-coated BSA NPs are promising delivery agents for local and systemic administration of BMP-2 in bone regeneration.

Cyclic shear loading with intermittent impulse loads can reliably create fracture in the pars interarticularis in ex vivo porcine spine segments. Subsequent cyclic anterior motion of the superior vertebra results in clinically-relevant spondylolysis and spondylolisthesis.

The standard evaluation methods for MFL-A inspections are based on simple calibration approaches that lead to stable results as long as the corrosion tends to be isolated and shallow. This paper presents a method suitable for complex and deep corrosion that utilizes FEM simulations on ultra-high resolution MFL-A data. It follows two main aspects: The first aspect is to learn from dig verifications by using laser scans of corrosion anomalies as a finite-element model to simulate the corresponding magnetic flux to confirm the magnetic flux measurement of the ILI tool. This way the simulation model is validated. The other aspect is to apply the achieved insights as a new depth sizing concept: the complete corrosion geometry as indicated by the ILI measurement is put into the validated FEM model to simulate the magnetic flux that should correspond to the one measured by the ILI tool. In this new sizing method the influence of complex corrosion is considered, as all surrounding features are part of the model. Several models are calculated in order to minimize the impact of ambiguity of depth results. This increases the accuracy and, ultimately, stabilize pipeline operators’ integrity assessments. In the big picture, novel approaches to MFL-A data interpretation, such as FEM, empower operators to make more informed decisions specific to their asset integrity management programs while reducing the costs, uncertainty and conservatism associated with these decisions.

Oil and gas pipelines, which transport large quantities of oil products and natural gas, are subject to pipeline failures caused by corrosion. Magnetic flux leakage (MFL) is one of the most popular non-destructive testing (NDT) techniques for the detection of pipeline corrosion. Since individual MFL is insensitive to the corrosion components that are parallel with its magnetic field, two types of MFL tools with perpendicular magnetic fields are usually employed in one inspection to detect all corrosion defects. This study applies probability of detection (POD) to quantitatively assess the detection capabilities of two individual MFL tools and their combination. Due to the characteristics of MFL inspection, this study proposes the construction of the POD model as a function of two geometric features, namely the volume and the orientation, which have a significant influence on the MFL signal response. Detection results from two MFL tools are integrated using logical OR operation to study the POD of their combination. With the proposed POD model, the minimum criteria that ensure a corrosion defect will be reliably detected by MFL tools are studied in this paper. The validity of the proposed POD model is justified on the data collected from an in-service pipeline.

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