RESUMEN
Intravenous lipid emulsions are biocompatible formulations used as clinical nutrition products and lipid-based delivery systems for sparingly soluble drugs. However, the particle-size distribution is associated with risks of embolism. Accordingly, the mean particle diameter (MPD) and particle-distribution tailing (characterized as the pFAT5 value) are critical quality attributes that ensure patient safety. Compliance with the limits stated in the United States Pharmacopoeia is ensured by high-pressure homogenization, the final step of the manufacturing process. The US Food and Drug Administration's Quality-by-Design approach requires a control strategy based on deep process understanding to ensure that products have a consistent and predefined quality. Here we investigated the process parameters of a jet-valve high-pressure homogenizer, specifically their effect on the MPD, pFAT5 value and droplet count (determined by microscopy) during the production of a Lipofundin MCT/LCT 20% formulation. We provide deep insight into droplet breakup and coalescence behavior when varying the process pressure, emulsion temperature and number of homogenization cycles. We found that high shear forces are not required to reduce the pFAT5 value of the particle distribution. Finally, we derived a control strategy for a rapid and cost-efficient two-cycle process that ensures patient safety over a large control space.
RESUMEN
Meckel's diverticula incarcerated in a hernia were first described anecdotally by Littré, a French surgeon, in 1700. Meckel, a German anatomist and surgeon, explained the pathophysiology of this disease 100 years later. In addition, a congenital paraduodenal mesocolic hernia, known as a Treitz hernia, is a rare cause of small bowel obstruction. These hernias are caused by an abnormal rotation of the primitive midgut, resulting in a right or left paraduodenal hernia. We treated a patient presenting with pain and diagnosed extraluminal air in the abdomen after a computed tomography examination. We performed a laparotomy and found a combination of these two seldomly occurring congenital diseases, incarceration and perforation of Meckel's diverticulum in a left paraduodenal hernia. We performed a thorough review of the literature, and this report is the first to describe a patient with a combination of these two rare conditions. We considered the case regarding the variety of terminology as well as the treatment options of these conditions.
RESUMEN
We propose a view-based approach to recognize humans from their gait. Two different image features have been considered: the width of the outer contour of the binarized silhouette of the walking person and the entire binary silhouette itself. To obtain the observation vector from the image features, we employ two different methods. In the first method, referred to as the indirect approach, the high-dimensional image feature is transformed to a lower dimensional space by generating what we call the frame to exemplar (FED) distance. The FED vector captures both structural and dynamic traits of each individual. For compact and effective gait representation and recognition, the gait information in the FED vector sequences is captured in a hidden Markov model (HMM). In the second method, referred to as the direct approach, we work with the feature vector directly (as opposed to computing the FED) and train an HMM. We estimate the HMM parameters (specifically the observation probability B) based on the distance between the exemplars and the image features. In this way, we avoid learning high-dimensional probability density functions. The statistical nature of the HMM lends overall robustness to representation and recognition. The performance of the methods is illustrated using several databases.
