174 research outputs found

    A study on multi-RIS for multi-user distributed MIMO systems

    Get PDF
    This paper presents a preliminary analysis on the impact of Reconfigurable Intelligent Surfaces (RISs) for the realization of multi-user Distributed multiple input multiple output (DMIMO) systems, where the distributed units are actually RISs. Assuming no direct link between the multi-antenna Access Point (AP) and the users, we design the joint transmit beamforming from the AP to the set of RISs associated to each user, performed via RIS phase shift shaping. In order to comply with the semipassive nature of RISs, the phase shifts are computed via a Genetic Algorithm (GA), where the optimization is based on the Signal-to-Leakage-and-Noise-Ratio (SLNR) precoding scheme. Numerical results confirm that this GA implementation significantly outperforms the common Maximum Ratio Beamforming (MRB) approach in terms of interference suppression and sumrate, but at the price of a significant increase in computational complexity. Our solution justify the interest of a multi-RIS system for spatial multiplexing, and opens to several further research directions

    Beware the wrong way! A report on gastrografin inhalation

    Get PDF
    An 83-year-old man was admitted to the Emergency Department of St. Anna University Hospital, Cona, Italy, after he had inhaled diatrizoate (gastrografin), a well-known hyperosmolar contrast agent, during an X-ray of the upper gastrointestinal tract. The family physician recommended the patient to take the test in order to demonstrate a possible hiatal hernia. While swallowing gastrografin he had an esophageal spasm (detected at fluoroscopy), which led to the inhalation of the contrast agent. After the episode, he was completely asymptomatic, eupnoeic, and with a good peripheral oxygen saturation. The physical examination was unremarkable. A chest X-ray of the lungs showed accumulation of the contrast agent in the distal bronchial tree (arrows in Figure 1A and B), with the right part being more involved because of the straight orientation of the right bronchus

    Dermoscopy and Reflectance Confocal Microscopy for Monitoring the Treatment of Actinic Keratosis with Ingenol Mebutate Gel: Report of Two Cases

    Get PDF
    Introduction: A relatively novel application for dermoscopy and reflectance confocal microscopy (RCM) is their use in the monitoring of topical treatment response for non-melanoma skin cancer. Actinic keratosis (AK) is the early phase of a multistep biologic continuum leading to invasive squamous cell carcinoma. A number of topical therapies are now available for the treatment of AK but their disadvantages include long treatment duration and prolonged local reactions. Ingenol mebutate is a newer therapy for AK which is only applied for 2 or 3 days. Case Report: Dermoscopy and RCM findings in two patients with AK treated with ingenol mebutate confirm that it induces rapid lesion necrosis and specific neutrophil-mediated, antibody-dependent cellular cytotoxicity. Necrosis occurs via mitochondrial membrane disruption, with subsequent eradication of residual tumor cells via transient inflammation. Local skin reactions to ingenol mebutate should be considered part of the drug’s mechanism of action rather than an adverse effect. Conclusion: Ingenol mebutate is a valuable therapy for the treatment of AK. This case report adds further evidence to the usefulness of dermoscopy and RCM in the assessment and monitoring of treatment outcome

    Dermoscopic Ulceration is a Predictor of Basal Cell Carcinoma Response to Imiquimod: A Retrospective Study

    Get PDF
    Imiquimod is considered one of the treatments of choice for low-risk superficial basal cell carcinoma (sBCC) and an alternative option for non-superficial tumours when surgery is contraindicated or not feasible (1\u20133). In addition to its well-known value in the diagnosis of BCC, dermoscopy has recently been shown to provide valid information about the histopathological subtype or the presence of clinically undetectable pigmentation (4\u20136). The aim of the present study was to investigate whether dermoscopic criteria (especially ulceration) of the primary tumour can predict a favourable response of BCC to imiquimod

    GREASE II. A phase II randomized, 12-month, parallel-group, superiority study to evaluate the efficacy of a Modified Atkins Diet in Autosomal Dominant Polycystic Kidney Disease patients

    Get PDF
    Introduction Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a condition that causes progressive renal function decline. Preclinical data suggest the presence of a profound metabolic derangement in ADPKD. Cystic cells shift their energy metabolism from oxidative phosphorylation to aerobic glycolysis, show inhibition of fatty acid oxidation and become glutamine and arginine dependent. Recent preclinical experiences have suggested beneficial effect in terms of reduction of cystic size, interstitial fibrosis and disease progression, targeting these deregulated metabolic pathways by ketosis induction. The dietetic approach to ADPKD, because of low cost and absence of toxicity, represents an interesting therapeutic strategy. Methods and analysis The protocol describes a phase II clinical trial that will evaluate the effect on Total Kidney Volume, safety and tolerability of a ketogenic diet in a selected ADPKD population. The trial will have, as secondary objective, the evaluation of the ability of the ketogenic diet to slow down the renal function decline. This will be a 12-month randomized, parallel group, two arm, superiority trial with 1:1 allocation to evaluate the efficacy of a Modified Atkins Diet protocol compared to a balanced normocaloric diet on 90 ADPKD patients. Dissemination The study results will be released to the patients and the medical community

    Cellular and Molecular Mechanism of Pulmonary Fibrosis Post-COVID-19: Focus on Galectin-1, -3, -8, -9

    Get PDF
    Pulmonary fibrosis is a consequence of the pathological accumulation of extracellular matrix (ECM), which finally leads to lung scarring. Although the pulmonary fibrogenesis is almost known, the last two years of the COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its post effects added new particularities which need to be explored. Many questions remain about how pulmonary fibrotic changes occur within the lungs of COVID-19 patients, and whether the changes will persist long term or are capable of resolving. This review brings together existing knowledge on both COVID-19 and pulmonary fibrosis, starting with the main key players in promoting pulmonary fibrosis, such as alveolar and endothelial cells, fibroblasts, lipofibroblasts, and macrophages. Further, we provide an overview of the main molecular mechanisms driving the fibrotic process in connection with Galactin-1, -3, -8, and -9, together with the currently approved and newly proposed clinical therapeutic solutions given for the treatment of fibrosis, based on their inhibition. The work underlines the particular pathways and processes that may be implicated in pulmonary fibrosis pathogenesis post-SARS-CoV-2 viral infection. The recent data suggest that galectin-1, -3, -8, and -9 could become valuable biomarkers for the diagnosis and prognosis of lung fibrosis post-COVID-19 and promising molecular targets for the development of new and original therapeutic tools to treat the disease

    Prevalence and natural history of potential coeliac disease in adult patients.

    Get PDF
    OBJECTIVE: Potential celiac disease (PCD) is a form of CD characterized by positive endomysial/tissue transglutaminase antibodies and a preserved duodenal mucosa despite a gluten-containing diet (GCD); it can evolve into flat, active CD. This evolution is, however, not certain. Our aim was to retrospectively study the prevalence and the natural history of adult patients with PCD. METHODS: The clinical notes of all 47 patients with PCD attending our clinic between September 1999 and October 2011 were retrospectively reevaluated. To study their clinical features, patients with active CD, randomly selected and matched for sex and date of birth, served as controls. Symptoms, associated diseases, familiarity, and laboratory data at diagnosis were compared. RESULTS: Prevalence of PCD among all celiac patients directly diagnosed in our center was 42/187, (1/4.4, 18.3%, 95% confidence interval (CI) 13.3-23.4%). Age at diagnosis, laboratory data, prevalence of symptoms, associated diseases, and familiarity for CD did not differ between patients with PCD and those with active CD. Some patients with PCD maintained a normal duodenal mucosa for many years and their symptoms spontaneously improved despite maintaining a GCD. CONCLUSIONS: PCD is not a rare form of CD. Having found no difference at all in age at diagnosis and clinical features between PCD and active CD could suggest that PCD is not a prodrome of CD but is a separate entity that can only subsequently evolve into active CD

    A mixed-mode cohesive-zone model accounting for finite dilation and asperity degradation

    Get PDF
    A cohesive zone model is formulated to describe the mechanics of initiation and propagation of cracks and the associated asperity degradation and nonlinear dilation along structural interfaces of quasi-brittle materials, such as concrete, rocks and masonry, subjected to monotonic or cyclic loading. Using a two-scale approach, a cohesive-law is determined at each point of a smooth macroscale interface by resolving a problem at the micro-scale for a representative interface area (RIA), where the geometry of the asperities is modelled using three differently inclined microplanes. On each microplane a cohesive-frictional cohesive law is then used. In this paper, the finite depth of the asperities is accounted for by considering the progressive reduction in contact area between each couple of interfacing microplanes for increasing opening (macro-scale) relative-displacement. Furthermore, the rupture of the asperities and associated flattening of the fracture surface is captured by a progressive reduction of the inclination angles of the microplanes in the RIA. Numerical examples are reported to assess the sensitivity of the shear-stress slip curves and of the nonlinear dilation upon the geometry of the asperities in the RIA. Numerical-experimental comparisons are then presented to illustrate the predictive capability of the model in simulating granite rock joints subjected to monotonic and cyclic shear loading and the concrete-bar interaction in a pull-out test
    • …
    corecore