457 research outputs found

    H^s versus C^0-weighted minimizers

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    We study a class of semi-linear problems involving the fractional Laplacian under subcritical or critical growth assumptions. We prove that, for the corresponding functional, local minimizers with respect to a C^0-topology weighted with a suitable power of the distance from the boundary are actually local minimizers in the natural H^s-topology.Comment: 15 page

    On the Dynamics of solitons in the nonlinear Schroedinger equation

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    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

    A critical fractional equation with concave-convex power nonlinearities

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    none4sìIn this work we study a fractional critical problem with concave-convex nonlinearities. Our main results show the existence and multiplicity of solutions to this problem for different values of the real parameter appearing in the equation. The dependency on this parameter changes according to whether we consider the concave power case or the convex power case. These two cases will be treated separatelyopenBarrios B; Colorado E; Servadei R; Soria FBarrios, B; Colorado, E; Servadei, Raffaella; Soria, F

    Regularity for the fractional p-Laplace equation

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    Higher Sobolev and Hölder regularity is studied for local weak solutions of the fractional p-Laplace equation of order sin the case p≥2. Depending on the regime considered, i.e.

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

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    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

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

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    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

    A Multicentric European Clinical Study on Custom-Made Porous Hydroxyapatite Cranioplasty in a Pediatric Population

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    Background: Cranioplasty (CP) is a surgical intervention aiming to re-establish the integrity of skull defects. Autologous bone and different heterologous materials are used for this purpose, with various reported related complications, especially in children.This study aims to evaluate the rate of complication in a multicentric cohort of pediatric patients treated by porous hydroxyapatite (PHA) CP implantation and to assess the reliability of post-marketing clinical data collected by a manufacturing company. Methods: The authors proactively collected clinical data from 20 institutions in different European countries for patients under the age of 16 treated with a PHA implant. The data were obtained by conducting an on-site interview with physicians in charge of the patients (Post-Marketing Surveillance, PMS group). The endpoints were the incidence of adverse events and related implant removal. The clinical data were compared to the company-based register including all patients under the age of 16 who received the same implant from January 1, 2004 to December 31, 2020, and the collecting complications voluntarily reported by surgeons (Database, DB group). Results: The two groups were similar in terms of demographic characteristics and rate of complications. In the PMS group, a total of 11 (16.9%) complications were reported in the group of 65 patients that were proactively collected. Both fractures and infections were the most common complications with 4 cases each (6.2%). In the case of both infections and fractures, revision surgery was required for only one patient (1.5%). Three (4.5%) cases of displacements were reported, and in one (1.5%) case, a surgical revision was required, for a total of 3 (4.5%) cases requiring surgical revision. The average follow-up was 26.7 months. Conclusions: Different from a previous study on adult age, pediatric neurosurgeons are more prone to report even to the manufacturing company complications related to skull reconstruction in children. Therefore, these data can be compared with those of other clinical studies. The PHA CP in this series of 65 patients presents a complication rate collected on-site that is similar to other heterologous materials

    Aluminum concentration is associated with tumor mutational burden and the expression of immune response biomarkers in colorectal cancers

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    Environmental pollution poses a significant risk to public health, as demonstrated by the bioaccumulation of aluminum (Al) in colorectal cancer (CRC). This study aimed to investigate the potential mutagenic effect of Al bioaccumulation in CRC samples, linking it to the alteration of key mediators of cancer progression, including immune response biomarkers. Aluminum levels in 20 CRC biopsy samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The results indicated that Al bioaccumulation occurred in 100% of the cases. A correlation between Al levels and tumor mutation burden was observed. Furthermore, RNA sequencing revealed a significant association between Al concentration and the expression of the immune checkpoint molecule CTLA-4. Although correlations with PD-1 and PD-L1 were not statistically significant, a trend was observed. Additionally, a correlation between Al levels and both the presence of myeloid cells and IFN gamma expression was detected, linking Al exposure to inflammatory responses within the tumor microenvironment. These findings suggested that Al can play a role in CRC progression by promoting both genetic mutations and immune evasion. Given the ubiquitous presence of Al in industrial and consumer products, dietary sources, and environmental pollutants, these results underscored the need for stricter regulatory measures to control Al exposure
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