Towards an Efficient Finite Element Method for the Integral Fractional Laplacian on Polygonal Domains

We explore the connection between fractional order partial differential equations in two or more spatial dimensions with boundary integral operators to develop techniques that enable one to efficiently tackle the integral fractional Laplacian. In particular, we develop techniques for the treatment of the dense stiffness matrix including the computation of the entries, the efficient assembly and storage of a sparse approximation and the efficient solution of the resulting equations. The main idea consists of generalising proven techniques for the treatment of boundary integral equations to general fractional orders. Importantly, the approximation does not make any strong assumptions on the shape of the underlying domain and does not rely on any special structure of the matrix that could be exploited by fast transforms. We demonstrate the flexibility and performance of this approach in a couple of two-dimensional numerical examples

On the Dynamics of solitons in the nonlinear Schroedinger equation

We study the behavior of the soliton solutions of the equation i((\partial{\psi})/(\partialt))=-(1/(2m)){\Delta}{\psi}+(1/2)W_{{\epsilon}}'({\psi})+V(x){\psi} where W_{{\epsilon}}' is a suitable nonlinear term which is singular for {\epsilon}=0. We use the "strong" nonlinearity to obtain results on existence, shape, stability and dynamics of the soliton. The main result of this paper (Theorem 1) shows that for {\epsilon}\to0 the orbit of our soliton approaches the orbit of a classical particle in a potential V(x).Comment: 29 page

Development of UHTCMCs via water based ZrB2 powder slurry infiltration and polymer infiltration and pyrolysis

Cf/ZrB2-SiC ultra-high temperature composites were manufactured via aqueous slurry impregnation coupled with polymer infiltration and pyrolysis, using a allylhydrido polycarbosilane precursor. For the first time we used ultra-high modulus pitch-based carbon fibres for the PIP process, investigating three different architectures, 0/0°, 0/90°, and 2D. Microstructure, mechanical properties and oxidation resistance in air at 1650 °C were investigated. As expected, the mechanical properties showed the tendency to decrease with increase of the preforms complexity, due to the higher amount of flaws and residual stresses. For instance, the flexural strength was approaching 500 MPa for 0/0°, 370 MPa for 0/90° and 190 MPa for 2D. The materials showed an optimal resistance to oxidation at 1650 °C thanks to formation of a viscous borosilicate glass that guaranteed a self-healing functionality

Diagnosing milk aspiration as a cause of death in sudden unexpected infant death: forensic insights from post-mortem analysis impacting criminal investigations

Sudden unexpected infant death (SUID) encompasses both explained and unexplained infant fatalities. When a comprehensive investigation yields inconclusive results, the case is classified as sudden infant death syndrome (SIDS). On the other hand, the most frequent non-SIDS diagnoses may be attributed to specific causes of death including a heterogeneous spectrum of conditions and disorders (e.g., trauma, asphyxia, suffocation, infection and metabolic diseases). Although rare, milk aspiration is a recognized cause of SUID that can lead to acute respiratory failure. This case report describes the death of a three-month-old infant found unresponsive in a traditional African baby carrier. Gross examination revealed no significant anomalies other than increased lung weight and the presence of milk-like material in the airways, alveoli, and stomach. Histological and ultrastructural analyses identified granular brownish material with birefringent globules in the lungs, consistent with aspirated milk. Immunohistochemical staining was positive for beta-lactoglobulin, confirming formula milk aspiration. This evidence was crucial in excluding maternal negligence as a cause of death, instead supporting an ante-mortem aspiration event resulting from regurgitation. This case highlights the diagnostic challenges associated with fatal milk aspiration and emphasizes the critical importance of a multidisciplinary approach. The integration of clinical history, autopsy findings, and advanced histopathological techniques is essential for accurately determining the cause of death and ensuring a sound legal assessment within the Courtroom setting

Understanding practice: the factors that influence management of mild traumatic brain injury in the emergency department-a qualitative study using the Theoretical Domains Framework

Background: Mild traumatic brain injury is a frequent cause of presentation to emergency departments. Despite the availability of clinical practice guidelines in this area, there is variation in practice. One of the aims of the Neurotrauma Evidence Translation program is to develop and evaluate a targeted, theory- and evidence-informed intervention to improve the management of mild traumatic brain injury in Australian emergency departments. This study is the first step in the intervention development process and uses the Theoretical Domains Framework to explore the factors perceived to influence the uptake of four key evidence-based recommended practices for managing mild traumatic brain injury. Methods: Semi-structured interviews were conducted with emergency staff in the Australian state of Victoria. The interview guide was developed using the Theoretical Domains Framework to explore current practice and to identify the factors perceived to influence practice. Two researchers coded the interview transcripts using thematic content analysis. Results: A total of 42 participants (9 Directors, 20 doctors and 13 nurses) were interviewed over a seven-month period. The results suggested that (i) the prospective assessment of post-traumatic amnesia was influenced by: knowledge; beliefs about consequences; environmental context and resources; skills; social/professional role and identity; and beliefs about capabilities; (ii) the use of guideline-developed criteria or decision rules to inform the appropriate use of a CT scan was influenced by: knowledge; beliefs about consequences; environmental context and resources; memory, attention and decision processes; beliefs about capabilities; social influences; skills and behavioral regulation; (iii) providing verbal and written patient information on discharge was influenced by: beliefs about consequences; environmental context and resources; memory, attention and decision processes; social/professional role and identity; and knowledge; (iv) the practice of providing brief, routine follow-up on discharge was influenced by: environmental context and resources; social/professional role and identity; knowledge; beliefs about consequences; and motivation and goals. Conclusions: Using the Theoretical Domains Framework, factors thought to influence the management of mild traumatic brain injury in the emergency department were identified. These factors present theoretically based targets for a future intervention

Traumatic brain injury – global collaboration for a global challenge

Even though, low- and middle-income countries (LMICs) are facing a far greater traumatic brain injury (TBI) burden compared to high-income countries (HICs), agency funding and multi-centre research efforts have had a disproportionately greater focus on HICs.1 Initiatives, such as InTBIR,2 are advancing TBI care in HICs but the participation of LMICs has been very limited. Additionally, multicentre trials in TBI, with very few exceptions, have predominantly focused on HIC populations.NIHR Global Heath Researc

Elevated temperature tensile and bending strength of ultra-high temperature ceramic matrix composites obtained by different processes

Publisher Copyright: © 2023 Elsevier LtdThis paper presents a comparison of microstructures and mechanical properties of different ZrB2-based CMCs, which were manufactured in the frame of the Horizon 2020 European C3HARME research project through different processes: slurry infiltration and sintering (SIS), polymer infiltration and pyrolysis (PIP) and radio frequency chemical vapour infiltration (RF-CVI). Tensile testing with a novel optimized shape of the specimens was performed and compared with the results of flexural tests to assess the structural properties. For the first time, tensile tests up to 1600 °C were carried out on UHTCMCs. Despite the different microstructural features, all the ZrB2-based CMCs demonstrated excellent structural properties even at elevated temperature. The characterization shows how the different amount of porosity and fibre properties, such as its stiffness, strength and elongation, affected the mechanical behaviour of the C3HARME's composites. Finally, the role of the high level of residual thermal stresses is discussed.This work has received funding from the European Union’s Horizon 2020 “Research and innovation programme” under grant agreement No 685594 (C3HARME). The authors greatly acknowledge Airbus Defence and Space GmbH for the collaboration and supplying materials. This work has received funding from the European Union's Horizon 2020 “Research and innovation programme” under grant agreement No 685594 (C3HARME). The authors greatly acknowledge Airbus Defence and Space GmbH for the collaboration and supplying materials.Peer reviewe

Predicting intracranial lesions by antiplatelet agents in subjects with mild head injury

International audienceBackground: The effect of pre-injury antiplatelet treatment in the risk of intracranial lesions in subjects after mild head injury (Glasgow Coma Scale 14-15) is uncertain. Methods: We aimed to determine the potential risk, considering its increasing use in guidelines on cardiovascular disease prevention and aging of the trauma population in Europe. Patients: We analyzed the interaction of antiplatelet therapy with the prediction variables of main decision aids in 14,288 consecutive adolescent and adult subjects with mild head injury. Measurements: Any intracranial lesion at CT scan was selected as outcome measure in a multivariable logistic regression analysis. Findings: Intracranial lesions were demonstrated in 880 cases (6.2%), with an unfavorable outcome at 6 months in 86 (0.6%). Antiplatelet drugs were recorded in 10% of the entire cohort (24.7% in the group over 65 years). They increased the risk of intracranial lesions at univaried analysis (odds ratio - OR, 2.6; 95% confidence interval - 95% CI 2.2¨C3.1), interacting with age at multivariate analysis (antiplatelet: OR, 2.7 (1.9¨C3.7); age ¡Ý 75 years, 1.4 (1.0¨C1.9)). The inclusion of these two variables to those included in previous decision aids for CT scanning (GCS, neurodeficit, post-traumatic seizures, suspected skull fracture, vomiting, loss of consciousness, coagulopathy) predicted intracranial lesions with a sensitivity of 99.7% (95% CI 98.9¨C99.8) and a specificity of 54.0% (95%CI 53.1¨C54.8), with a CT ordering-rate of 49.3% (undetermined events, 0.2:1000). Interpretation: Antiplatelet drugs need to be considered in future prediction models on mild head injury, considering their increasing use and progressive aging of the trauma populatio

Aluminium bioaccumulation in colon cancer, impinging on epithelial-mesenchymal-transition and cell death

We investigated the presence of aluminium (Al) in human colon cancer samples and its potential association with biological processes involved in cancer progression, such as epithelial to mesenchymal transition (EMT) and cell death. 25 consecutive colon samples were collected from patients undergoing colonic resection. Both neoplastic and normal mucosa were collected from each patient and subjected to histological, ultrastructural and immu-nohistochemical analyses. Moreover, colon samples from two Al-positive patients underwent multi-omic ana-lyses, including whole genome sequencing and RNA sequencing (RNAseq). Morin staining, used to identify in situ aluminium bioaccumulation, showed the presence of Al in tumor areas of 24 % of patients. Transmission electron microscopy and energy-dispersive X-ray microanalysis confirmed the presence of Al specifically in intra-cytoplasmic electrondense nanodeposits adjacent to mitochondria of colon cancer cells. Immunohistochemical analyses for vimentin and nuclear beta-catenin were performed to highlight the occurrence of the EMT phenomenon in association to Al bioaccumulation. Al-positive samples showed a significant increase in both the number of vimentin-positive and nuclear beta-catenin-positive cancer cells compared to Al-negative samples. Moreover, Al -positive samples exhibited a significant decrease in the number of apoptotic cells, as well as the expression of the anti-apoptotic molecule BCL-2. Multi-omic analyses revealed a higher tumor mutational burden (TMB) in Al -positive colon cancers (n = 2) compared to a control cohort (n = 100). Additionally, somatic mutations in genes associated with EMT (GATA3) and apoptosis (TP53) were observed in Al-positive colon cancers. In conclusion, this study provides the first evidence of Al bioaccumulation in colon cancer and its potential role in modulating molecular pathways involved in cancer progression, such as EMT and apoptosis. Understanding the molecular mechanisms underlying Al toxicity might contribute to improve strategies for prevention, early detection, and targeted therapies for the management of colon cancer patients