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Abstract Unraveling the effects of continuous dislocation interactions with interfaces, particularly at the nanometer length scales, is key to a broader understanding of plasticity, to material design and to material certification. To this end, this work proposes a novel discrete dislocation dynamics-based model for dislocation interface interactions tracking the fate of residual dislocation on interfaces. This new approach is used to predict the impact of dislocation/interface reactions on the overall mechanical behavior of accumulative roll bonded nanometallic laminates. The framework considers the dynamic evolution of the interface concurrent with a large network of dislocations, thus, accounting for the local short and long range effects of the dislocations under the external boundary conditions. Specifically, this study focuses on two-phase Fe/Cu nanometallic laminates, and investigates the role of the underlying elastic and plastic contrast of the Fe and the Cu layers on the composite response of the material. Moreover, the role of initial microstructures, resulting from processing is also investigated. Subsequently, the model is used to examine the effect of layer thickness and interface orientation relationship on the residual stresses of the relaxed microstructure. The associated mechanical response of these laminates are compared when loaded under normal direction compression, as well as shear compression. Finally, this work predicts a dominant effect of the layer thickness, as compared to the interface orientation relationship, on the macroscopic response and on the residual stresses of these nanolaminates, while the local dislocation transmission propensity through the interface is significantly influenced by the corresponding orientation relationship.

Abstract Purpose To describe clinical and biological features and the outcomes of patients admitted for histoplasmosis in two intensive care units (ICU) in French Guyana and in the French West Indies (Guadeloupe). Methods All patients admitted to these two ICUs for culture-proven histoplasmosis between January 2014 to August 2022 were included in the study. Using univariate and multivariate analysis, we assessed risk factors at ICU admission that were associated with death. Results Forty patients were included (65% men). Median age was 56 years and simplified acute physiologic score (SAPS) II was 65. HIV was found in 58%, another immunodeficiency was identified in 28%, and no underlying immunodeficiency could be identified in 14% of patients. Within the first 24 h of ICU admission, 85% of patients had acute respiratory failure, 78% had shock, 30% had coma, and 48% had hemophagocytic lymphohistiocytosis. Mechanical ventilation was instituted in 78% of patients and renal replacement therapy in 55%. The 30-day mortality was 53%. By multivariate analysis, factors independently associated with 30-day mortality were SOFA score (odds ratio [OR] 1.5, 95% confidence interval [CI] [1.1–2.1]), time between symptom onset and treatment per day (OR 1.1, 95% CI 1.0–1.1), and hemophagocytic lymphohistiocytosis (OR 6.4, 95% CI 1.1–47.5). Conclusion Histoplasmosis requiring ICU admission is a protean disease with multiple and severe organ involvement. Immunodeficiency is found in most patients. The prognosis remains severe despite appropriate treatment and is worsened by late treatment initiation.

Abstract Background and study aims Egypt has been a pioneer in implementing a nationwide HCV screening and treatment program. Assessment of liver fibrosis after HCV eradication is important. The value of liver stiffness measurement (LSM) for this purpose is still debated. The aim of this prospective longitudinal study was to assess LSM evolution after HCV eradication. Patients and methods One-hundred and three HCV patients, treated with a standard DAA regimen (sofosbuvir/daclatasvir for 3 months), underwent LSM before and 24 weeks after the end of treatment. Patients were classified into 3 groups according to baseline LSM (Baveno VI): group 1: patients without compensated advanced chronic liver disease (cACLD) (LSM 15 kPa). Results The characteristics of patients were as follows: mean age 55 ± 10 years, males 48.5%, and BMI 26.31 ± 3.33 kg/m2. All patients were Child–Pugh score A and achieved SVR at W24. A significant LSM decrease was observed at W24 compared to baseline: all patients: 5.8 vs. 8.8 kPa, p = 0.002; group 1: 4.75 vs. 6.0 kPa, p = 0.0001; group 2 11.9 vs. 12.6 kPa, p = 0.042; and group 3: 24.2 vs. 28.3 kPa, p = 0.0001. Group 1 had the highest LSM decline (23.83%), followed by group 3 (14.3%) and group 2 (8.4%). Conclusion HCV eradication was associated with a significant LSM decrease in all groups of patients. This is likely related to improvement of fibrosis, but its relation to improvement of necro-inflammation cannot be excluded. Longer follow-up of fibrosis in these patients is needed.

Abstract Introduction Costs related to road crashes represent an important societal burden. Additionally they constitute an essential input variable to assess the cost efficiency of road safety measures. While most attention is usually spent on costs related to fatal crashes, this paper focuses on costs related to serious injuries. Method A review of these costs is presented based on different data sets and methods. Results A survey collecting crash cost estimates in European countries shows considerable variation in the costs related to serious injuries. The reported cost per serious injury varies between €28,205 and €975,074 and the total costs related to serious injuries vary between 0.04% and 2.7% of a country’s GDP. The applied methodology to estimate human costs appears to have a large influence. Other potential explanations are the applied definition for seriously injured victims, the registration procedure of crashes with serious injuries and the cost components that are included. Detailed analyses of medical costs and production loss that are based on country-specific datasets show the importance of assessing medical costs on the long term and taking into account the variation of these costs for different subgroups of traffic victims. A comparison of approaches to estimate monetary values for human costs shows that most countries use the Willingness To Pay method. While having a sound theoretical background, this method is rather limited in the specification of injuries. The use of Quality Adjusted Life Years gives the possibility to provide values for a larger diversity of injury types.

Abstract A mesoscale model is introduced to study the dynamics of material defects lying at interface junctions. The proposed framework couples the dynamics of discrete dislocation and disclination lines. Disclinations are expected to be natural defects at interface junctions; their presence serving the purpose of accommodating discontinuities in rotation fields at material interface junctions. Crystallography-based rules are proposed to describe the kinematics of disclination motion. A discrete-continuous couple-stress framework, in which discrete defect lines are introduced as plastic eigenstrains and eigencurvatures, is proposed to explicitly follow the dynamics of interfacial defects. The framework is then applied to study 101̄2 $\left (10\bar {1}2\right)$ twin transverse propagation and thickening in magnesium. Focusing first on the case of a twin domain, It is shown that a disclination based representation of twin domains allows for an appropriate mechanistic description of the kinematics of shear transformations. In what concerns twin thickening, the stability of defects at twin interfaces is further studied. To this end, a 3D crater lying on a twin interface is described as a dipole of disclination loops. Upon self-relaxation, it is found that out of plane motion of disclinations followed by the nucleation of twinning dislocations can be activated; thereby showing that conservative non-planar motion of disclinations can be thermodynamically favorable; mechanism that had been postulated some 50 years ago.