Ethyl­enediammonium tetra­aqua­disulfato­cadmate

The crystal structure of the title compound, [NH3(CH2)2NH3][Cd(SO4)2(H2O)4], consists of [Cd(SO4)2(H2O)4]2− anions that are built from octa­hedral Cd(H2O)4O2 and SO4 tetra­hedral units linked by corner sharing. The ethyl­ene­diamminium cations are linked to the anions via N—H⋯O hydrogen bonds. The asymmetric unit contains one-half of the compound, the other half being related to the first by an inversion centre. The crystal structure presents alternate stacking of the inorganic and organic layers along the crystallographic b axis. The structure cohesion and stability is further assured by O(water)—H⋯O hydrogen bonds

Rigorous Estimates for Effective Creep-coefficients of Microcracked Masonry Accounting for Cracks Interactions

Based on the association of finite elements homogenization method and a rigorous homogenization scheme accounting for crack interactions, this paper provides rigorous predictions for the local and effective properties of microcracked viscoelastic masonry with or without creep of bricks. For the sake of simplicity, viscoelastic brick and mortar are assumed to follow the Generalized Maxwell rheological model and to be respectively safe and microcracked. In the mortar, the distribution of microcracks orientations is assumed to be random. Two steps are followed. The first one is based on the identification at the short and long terms of an approximate analytical creep function for the mortar. This step relies on the coupling between the Griffith’s brittle fracture theory and a rigorous homogenization scheme - the Ponte Castañeda & Willis model - accounting for crack interaction instead of the dilute scheme adopted previously in Rekik et al. Two cases are considered: open and closed cracks. The first step allows to avoid recourse to 'heavy' numerical inversion of the Laplace-Carson transform. The second one provides overall creep coefficients of masonry by means of periodic homogenization carried out by finite elements method. For open cracks state, time-dependent crack density is investigated. The proposed model is validated by comparison with an analytical one available for a compressed masonry wall with "standard" viscoelastic mortar joints. Effect induced by microcracks is also highlighted by comparison with uncracked masonry. At last, results provided by the proposed model can be considered to be rigorous solution improving on dilute estimates for the creep behavior of microcracked mortar and demonstrating the interest to not neglect both cracks interactions and creep of bricks units.&nbsp

Le métier du professeur de musique

Music, taught in schools, is an important subject which contributes to the development of students and their integration into society. The teacher must therefore be aware of the programs for this subject, its general framework and its content, while becoming aware of the identity of the musician who could bring together the specificities of the teacher and those of the musician and distinguish between the function of learning and that of listening and enjoyment to achieve the objectives of teaching musical subject matter to a specific category of society such as children and students. The objectives of music education lie essentially in the awakening of musical sense in children, the development of musical skills and abilities in students, and the guarantee of continuous communication between the receiver and the musical subject. inside and outside the framework of school education, especially since this subject has a particular impact on students. We therefore carried out this research to clarify the methods and mechanisms of the discourse that must be established between the musician and the receive

Brain atrophy patterns in multiple sclerosis patients treated with natalizumab and its clinical correlates

BACKGROUND: Multiple sclerosis (MS) is defined as a demyelinating disorder of the central nervous system, witnessing over the past years a remarkable progress in the therapeutic approaches of the inflammatory process. Yet, the ongoing neurodegenerative process is still ambiguous, under‐assessed, and probably under‐treated. Atrophy and cognitive dysfunction represent the radiological and clinical correlates of such process. In this study, we evaluated the effect of one specific MS treatment, which is natalizumab (NTZ), on brain atrophy evolution in different anatomical regions and its correlation with the cognitive profile and the physical disability. METHODS: We recruited 20 patients diagnosed with relapsing‐remitting MS (RR‐MS) and treated with NTZ. We tracked brain atrophy in different anatomical structures using MRI scans processed with an automated image segmentation technique. We also assessed the progression of physical disability and the cognitive function and its link with the progression of atrophy. RESULTS: During the first 2 years of treatment, a significant volume loss was noted within the corpus callosum and the cerebellum gray matter (GM). The annual atrophy rate of the cortical GM, the cerebellum GM, the thalamus, the amygdala, the globus pallidus, and the hippocampus correlated with greater memory impairment. As for the third and fourth years of treatment, a significant atrophy revolved around the gray matter, mainly the cortical one. We also noted an increase of the thalamus volume. CONCLUSION: Atrophy in RR‐MS patients treated with NTZ is regional and targeting highly cognitive regions mainly of the subcortical gray matter and the cerebellum. The cerebellum atrophy was a marker of physical disability progression. NTZ did not accelerate the atrophy process in MS and may play a neuroprotective role by increasing the thalamus volume