Experimental test and numerical shape optimization of a point pivoted absorber for wave energy conversion

This paper presents a numerical study on an innovative system for converting energy from waves. It consists of a point pivoted body which oscillates in presence of waves. The system uses a linear electrical generator which converts floating movements of the buoyant body into electrical power. The buoyant body floats, describing an arc, by means of two hinges. A suitable Power Take-off Device (PTO) is placed between buoy support arms and the fixed structure and has the function to convert the mechanical power of the linear oscillating motion of the connecting piston into electrical power. A design assumption is made on the PTO control system: PTO reaction force is assumed to be linearly dependent on piston oscillation velocity with a given force-speed gain. This coefficient is strictly connected to electrical generator characteristics and its value has an effect on power conversion efficiency . A scaled model of this system has also been tested in the wave/towing tank facility of Department of industrial Engineering (DII) of University of Naples “Federico II”. A variety of numerical analyses, such as potential flow simulations and Unsteady Reynolds Averaged Navier-Stokes (URANS) simulations, have been performed to predict the system performances. Numerical and experimental analyses have included the performances of the baseline geometry, both in free response and under wave excitation, in order to characterize the response of the system, and results have been used to understand which parameters affect more the power production. Finally a numerical optimization procedure has been carried out to optimize the shape of the converter with the final objective of increasing the generated power, eventually imposing a constraint on the amount of immersed volume. In this way, a modified configuration has been predicted with higher power output and the same value of submerged volume, but with different shape

Effectiveness of high dose sublingual immunotherapy to induce a stepdown of seasonal asthma: a pilot study

There is ample evidence to support the efficacy of sublingual immunotherapy (SLIT) on allergic rhinitis, while there is less solid data regarding asthma. We evaluated the effects of a high dose birch SLIT on birch-induced rhinitis and asthma in a controlled study

A systematic review of the literature on the role of tracheostomy in COVID-19 patients

– The Coronavirus Disease 2019 (COVID-19) is a viral infection caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which emerged in East Asia and spread around the world from December 2019. The most severe stage of COVID-19 pathology is characterized by respiratory distress requiring intubation. In specific cases, tracheostomy is indicated to ensure the safety of the procedure. The aim of our study was to analyze the scientific literature identifying the indications for tracheostomy and safety precautions to reduce contamination. We analyzed the literature from February 2003 to April 2020, including papers on pandemics of other coronaviruses, such As Severe Acute Respiratory Syndrome Coronavirus 1 and Middle East Respiratory Syndrome Coronavirus, to obtain a variety of relevant information. We focused on indications for tracheostomy in patients affected by COVID-19 or related viruses and the measures adopted to perform a safe procedure. We included 35 papers, of which 24 (68.57%) discussed guidelines for tracheostomy indications. All 35 studies discussed the procedures for performing tracheostomy safely. Data obtained indicated that the authors generally agreed on safety measures but expressed different opinions about indications. Therefore, we provided guidelines addressing safety recommendations. After the pandemic has been resolved, we plan to conduct an international retrospective study to identify the criteria for tracheostomy indications

Diagnostic performance of inflammatory biomarkers and cytological analysis in salivary gland tumors

Background: This study aimed to evaluate the diagnostic performance of serum inflammatory biomarkers in salivary gland tumors with dubious results following cytological analysis. Methods: A retrospective analysis of 239 cases following surgery between January 2011 and June 2022 was performed. Receiver Operating Characteristic curves were drawn and areas under the curves were computed to evaluate the diagnostic performance of the inflammatory biomarkers (SII, SIRI, PLR, and NLR). Optimal cut-offs for each marker were determined by maximizing the Youden index. Results: Analysis showed that among the major biomarkers examined, SIRI performed an AUC of 0.77. The best SIRI cut-off was 0.94 with an accuracy of 79.9%. The accuracy, sensitivity, and specificity of cytological analysis were 77.8%, 59.6%, and 90.7% respectively. By combining SIRI with cytological analysis we demonstrated an increase in sensitivity to 82.8%. Conclusions: Inflammatory biomarkers could be evaluated to support the diagnosis and treatment of salivary gland tumors in difficult cases

Sutureless Valve in Repeated Aortic Valve Replacement: Results from an International Prospective Registry

Objective: To report early and midterm results registry of patients undergoing repeated aortic valve replacement (RAVR) with sutureless prostheses from an international prospective registry (SURE-AVR). Methods: Between March 2011 and June 2019, 69 patients underwent RAVR with self-expandable sutureless aortic bioprostheses at 22 international cardiac centers.Results: Overall mortality was 2.9% with a predicted logistic EuroSCORE 11 of 10.7%. Indications for RAVR were structural valve dysfunction (84.1%) and infective prosthetic endocarditis (15.9%) and were performed in patients with previously implanted bioprostheses (79.7%), mechanical valves (15.9%), and transcatheter valves (4.3%). Minimally invasive approach was performed in 15.9% of patients. Rate of stroke was 1.4% and rate of early valve-related reintervention was 1.4%. Overall survival rate at 1 and 5 years was 97% and 91%, respectively. No major paravalvular leak occurred. Rate of pacemaker implantation was 5.8% and 0.9% per patient-year early and at follow-up, respectively. The mean transvalvular gradient at 1-year and 5-year follow-up was 10.5 mmHg and 11.5 mmHg with a median effective orifice area of 1.8 cm 2 and 1.8 cm 2 , respectively. Conclusions: RAVR with sutureless valves is a safe and effective approach and provides excellent clinical and hemodynamic results up to 5 years

Longitudinal transcriptomic and genetic landscape of radiotherapy response in canine melanoma

Canine malignant melanoma (MM) is a highly aggressive tumour with a low survival rate and represents an ideal spontaneous model for the human counterpart. Considerable progress has been recently obtained, but the therapeutic success for canine melanoma is still challenging. Little is known about the mechanisms beyond pathogenesis and melanoma development, and the molecular response to radiotherapy has never been explored before. A faster and deeper understanding of cancer mutational processes and developing mechanisms are now possible through next generation sequencing technologies. In this study, we matched whole exome and transcriptome sequencing in four dogs affected by MM at diagnosis and at disease progression to identify possible genetic mechanisms associated with therapy failure. According to previous studies, a genetic similarity between canine MM and its human counterpart was observed. Several somatic mutations were functionally related to MAPK, PI3K/AKT and p53 signalling pathways, but located in genes other than BRAF, RAS and KIT. At disease progression, several mutations were related to therapy effects. Natural killer cell-mediated cytotoxicity and several immune-system-related pathways resulted activated opening a new scenario on the microenvironment in this tumour. In conclusion, this study suggests a potential role of the immune system associated to radiotherapy in canine melanoma, but a larger sample size associated with functional studies are needed