Skin carcinoma of the face: surgery or radiotherapy?

Surgical exeresis and radiation therapy are effective means of treatment for facial carcinomas. In some areas that are difficult to manage (nose, ears, periorbital region), the respective importance of both approaches is discussed. We report on the retrospective study of 309 patients seen after a skin carcinology consultation in which a dermatologist, a surgeon and a radiotherapist were associated. These 309 patients, with a mean age of 73 years, presented with 375 carcinomas, i.e. 246 basal-cell (BC) and 119 epidermoid (EC) carcinomas. The most frequent sites were the nose (33.8% of BC), the inner canthus (12.7% of BC), the lower lip (23.8% of EC) and the ear (15.6% of EC). Management mainly consisted of surgery (50.8%) then Curie therapy (37%). The rate of recurrence was the same (10.5%) after surgery and radiation therapy. The study of the results leads us to advocating surgery for carcinomas of the ear (due to the occurrence of radiation necrosis in every third case after radiation therapy) and Curie therapy for carcinomas of the lower lid (except the inner canthus) because of recurrence in every second case treated with surgery. We currently prefer surgery for carcinomas of the lower lip (radiodermatitis in 11.8% of cases) and Curie therapy for the nose (lower rate of recurrence than with surgery). However, in the last two cases, the proposals for treatment should be confirmed by randomized studies. Thus facial carcinomas of the skin surrounding the orifices of the face and/or those that affect patients who are difficult to treat must be seen during a skin carcinology consultation by a dermatologist, a surgeon and a radiotherapist working together.(ABSTRACT TRUNCATED AT 250 WORDS)     

Development of a mannequin lab for clinical training in a chiropractic program

ObjectiveFaced with COVID-19 safety protocols that severely limited the ability to conduct chiropractic technique instruction in the usual manner, our university invested the resources to develop a new mannequin lab for hands-on training, which would help supplement the loss of person-to-person contact.MethodsTraining mannequins could enable student learning of palpation and adjustment skills while avoiding close human–human contact. The university had developed a mannequin over the previous 4 years consisting of a full-sized human torso with individually movable and palpable vertebrae, pelvis, and thighs. In the mannequin, 64 pressure sensors are attached to particular vertebral and skeletal landmarks and provide feedback on palpation location and level of force applied. We assembled 3 teams to produce 20 copies of that mannequin for student use.ResultsMannequins were produced in 7 weeks, and space was built out for a special lab. Faculty members are developing classroom procedures to introduce the mannequin to students, phase in the skills from static and motion palpation, and practice thrust performance.ConclusionThe production run was successful, and the resulting equipment, well-received by students and faculty. In addition to helping teach manual skills, the lab serves as a platform for educational research to test the efficacy of mannequin-based training protocols. With the pressure sensors on known locations along the spine, future research may be able to test the ability of students to identify and contact specific target locations for adjustive thrusts.     

Simulation of Continuous Dynamic Recrystallization Using a Level-Set Method

Dynamic recrystallization is one of the main phenomena responsible for microstructure evolution during hot forming. Consequently, obtaining a better understanding of dynamic recrystallization mechanisms and being able to predict them is crucial. This paper proposes a full-field numerical framework to predict the evolution of subgrain structures upon grain growth, continuous dynamic recrystallization, and post-dynamic recrystallization. To be able to consider a subgrain structure, two strategies are proposed. One relies on a two-step tessellation algorithm to generate a fully substructured microstructure. The second strategy enables for the simulation of the formation of new subgrains during hot deformation. Using these tools, the grain growth of a fully substructured microstructure is modeled. The influence of microstructure topology, subgrain parameters, and some remaining stored energy due to plastic deformation is discussed. The results highlight that the selective growth of a limited number of subgrains is observed only when mobility is a sigmoidal function of disorientation. The recrystallization kinetics predicted with different criteria for discrimination of recrystallized grains are quantitatively compared. Finally, the ability of the framework to model continuous dynamic and post-dynamic recrystallization is assessed upon a case study representative of the hot extrusion of a zircaloy-4 billet (T=650 °C;ε˙=1.0s−1;εf=1.35). The influence of grain boundary properties and nucleation rules are quantified to evaluate the model sensitivity and suitability. Application of these numerical tools to other thermomechanical conditions and microstructures will be presented in an upcoming article.