New insights into the biomechanics of Legg-Calvé-Perthes’ disease: The role of epiphyseal skeletal immaturity in vascular obstruction

ObjectivesLegg–Calvé–Perthes’ disease (LCP) is an idiopathic osteonecrosis of the femoral head that is most common in children between four and eight years old. The factors that lead to the onset of LCP are still unclear; however, it is believed that interruption of the blood supply to the developing epiphysis is an important factor in the development of the condition.MethodsFinite element analysis modelling of the blood supply to the juvenile epiphysis was investigated to understand under which circumstances the blood vessels supplying the femoral epiphysis could become obstructed. The identification of these conditions is likely to be important in understanding the biomechanics of LCP.ResultsThe results support the hypothesis that vascular obstruction to the epiphysis may arise when there is delayed ossification and when articular cartilage has reduced stiffness under compression.ConclusionThe findings support the theory of vascular occlusion as being important in the pathophysiology of Perthes disease

Lepton Flavor Violation and Collider Searches in a Type I + II Seesaw Model

Neutrino are massless in the Standard Model. The most popular mechanism to generate neutrino masses are the type I and type II seesaw, where right-handed neutrinos and a scalar triplet are augmented to the Standard Model, respectively. In this work, we discuss a model where a type I + II seesaw mechanism naturally arises via spontaneous symmetry breaking of an enlarged gauge group. Lepton flavor violation is a common feature in such setup and for this reason, we compute the model contribution to the $\mu \rightarrow e\gamma$ and $\mu \rightarrow 3e$ decays. Moreover, we explore the connection between the neutrino mass ordering and lepton flavor violation in perspective with the LHC, HL-LHC and HE-LHC sensitivities to the doubly charged scalar stemming from the Higgs triplet. Our results explicitly show the importance of searching for signs of lepton flavor violation in collider and muon decays. The conclusion about which probe yields stronger bounds depends strongly on the mass ordering adopted, the absolute neutrino masses and which much decay one considers. In the 1-5 TeV mass region of the doubly charged scalar, lepton flavor violation experiments and colliders offer orthogonal and complementary probes. Thus if a signal is observed in one of the two new physics searches, the other will be able to assess whether it stems from a seesaw framework.Comment: 41 pages, 1 figure, 2 table

Quality of relationships between residential staff and youth: A systematic review

Regardless of the type of residential care context, entering in care is an impactful event that involves the separation of young people from their relatives, as well as the need to adapt to a new context. This adaptation might be facilitated by the quality of relationships with professionals in these settings, which in turn may positively impact young people’s psychological adjustment. Purpose: The current systematic review aims to identify the factors that might be associated with quality relationships in residential homes (i.e., generalist care, therapeutic care, juvenile justice settings) at different ecological levels. Method: A systematic electronic search was conducted in eight databases: Academic Search Complete, APA PsycArticles, APA PsycINFO, Psychology and Behavioral Sciences Collection, ERIC, MEDLINE, Web of Science and Scopus, using a combination of words related with quality relationship, residential care, children, and adolescent. Based on the PRISMA statement, 919 manuscripts were yielded, and thirteen studies met the inclusion criteria. Results: Child (e.g., gender or age), professionals (e.g., professionals’ characteristics, behaviors, and skills), organizational (e.g., Ratios of children to professionals on staff) and cross-cutting factors (e.g., time spent together, length of relationship) were found to be associated with quality relationships between professionals and young people in care. Discussion: The residential care settings should be able to provide appropriate resources and services which address young people’s complex needs. Practical implications are discussed.info:eu-repo/semantics/publishedVersio

Thermal diffusion in solids : an overview

Thermal diffusion in liquids and gases has been the focus of a number of studies and is considered, at present, a reasonably wellknown topic. In solids though, the phenomena is far less understood namely in what regards the effects of thermal gradients upon the integrity and characteristics of materials. Furthermore it is not clear whether or not thermal diffusion can be used as a purificating method for solids. Yet, many current techniques such as the laser, used in metal working and other solids, induce strong thermal gradients being, therefore, potential cause for the occurrence of thermal diffusion. In this work, a survey and discussion of theoretical and experimental studies of thermal diffusion in solids is undertaken