A possible rheological model of gum candies

An appropriate rheological model can be used in production of good quality gum candy required by consumers. For this purpose Creep-Recovery Test (CRT) curves were recorded with a Stable Micro System TA.XT-2 precision texture analyser with 75 mm diameter cylinder probe on gum candies purchased from the local market. The deformation speed was 0.2 mm s−1, the creeping- and recovering time was 60 s, while the loading force was set to 1 N, 2 N, 5 N, 7 N, and 10 N. The two-element Kelvin-Voigt-model, a three-element model, and the four-element Burgers-model were fitted on the recorded creep data, and then the parameters of the models were evaluated. The best fitting from the used models was given by the Burgers model

Radical palliative surgery: new limits to pursue

This case report describes the radical subtotal palliative resection of a massive recurrent desmoid tumor encompassing the abdomen, pelvis, and groin in a child who was 13 years old at the time of initial resection. Given the extensive distribution of the tumor en bloc resection, which is the standard treatment of desmoid tumors, would have meant performing a hemipelvectomy and repair of a large abdominal wall defect, likely with skin grafts and mesh. The patient’s personal goals however were to alleviate the pain and limited mobility that would allow her to re-attend high school and appear normal to her peers. Therefore, palliative surgery was pursued and currently the patient is 5 years out from her last surgery doing well. We believe that the option of surgical palliation in this case was warranted and should be an option for similar cases in the future

Ectopic lymphoid structures in primary cutaneous melanoma.

Ectopic lymphoid structures have been described in several tumor types including metastatic lesions, but not primary tumors, of patients with melanoma. Here we present evidence of B-cell follicles in primary cutaneous melanomas, being present in 39 of 147 cases (27 %). B-cell clusters were associated with T lymphocytes, most of which belonging to CD45RO+ memory T cells. A network of CD21+ follicular dendritic cells was demonstrated in 8 of 22 cases studied (36 %). MECA-79+ HEV-like venules were observed in the neighborhood of the follicles in the majority of cases, however, their presence was not confined to tumors hosting ectopic lymphoid structures. The appearance of B-cell aggregates did not show association with the outcome of the disease, although a trend for their higher prevalence was observed in thicker tumors. Our results show that neogenesis of lymphoid structures does occur in primary melanomas, albeit with lower frequency compared to that reported in metastases

Mathematical modeling of a dip-coating process using concentrated dispersions

Industrial dip coating is a simple and easy to access technique that can be considered as a self-metered coating process. Practical applications of films obtained by this method include decorative, protective, and functional purposes. The objective of this work was to develop a 2D mathematical model of the fluid-dynamic variables of the dip-coating draining stage of a finite vertical plate, considering nonevaporative and isothermal conditions. Concentrated dispersions were considered, such as those whose rheological behavior was described by an extension of a theoretical rheological model proposed by Quemada. As a result, an analytical and simple mathematical model that relates the main fluid parameters could be obtained. The model was achieved based upon rigorous mass and momentum balances applied to the draining stage of a monophasic, isothermal, and nonevaporative system, where the highest forces are viscous and gravitational. Parameters that were estimated are the velocity profile, average velocity, flow rate, local thickness, and average thickness of the film. Finally, experimental validation was performed by using experimental data (rheological properties, densities, and average film thickness values) of several representative concentrated dispersions (emulsions and suspensions) obtained in this work and from the literature. All the information achieved in this study can be useful to control and predict the thickness and homogeneity of the film during an industrial coating process, in order to satisfy the quality requirements of the final product.Fil: Peralta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Meza, Barbara Erica del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin