Operational modal analysis of a spar-type floating platform using frequency domain decomposition method

System identification of offshore floating platforms is usually performed by testing small-scale models in wave tanks, where controlled conditions, such as still water for free decay tests, regular and irregular wave loading can be represented. However, this approach may result in constraints on model dimensions, testing time, and costs of the experimental activity. For such reasons, intermediate-scale field modelling of offshore floating structures may become an interesting as well as cost-effective alternative in a near future. Clearly, since the open sea is not a controlled environment, traditional system identification may become challenging and less precise. In this paper, a new approach based on Frequency Domain Decomposition (FDD) method for Operational Modal Analysis is proposed and validated against numerical simulations in ANSYS AQWA v.16.0 on a simple spar-type structure. The results obtained match well with numerical predictions, showing that this new approach, opportunely coupled with more traditional wave tanks techniques, proves to be very promising to perform field-site identification of the model structures

Progress on the experimental set-up for the testing of a floating offshore wind turbine scaled model in a field site

This document describes design and realization of a small-scale field experiment on a 1:30 model of spar floating support structure for offshore wind turbines. The aim of the experiment is to investigate the dynamic behaviour of the floating wind turbine under extreme wave and parked rotor conditions. The experiment has been going on in the Natural Ocean Engineering Laboratory of Reggio Calabria (Italy). In this article, all the stages of the experimental activity are presented, and some results are shown in terms of motions and response amplitude operators. Finally, a comparison with corresponding results obtained using ANSYS AQWA software package is shown, and conclusions are drawn. The presented experimental set-up seems promising to test offshore floating structures for marine renewable energy at a relatively large scale in the Natural Ocean Engineering Laboratory field site

Transfer of malignant traits as opposed to migration of cells: A novel concept to explain metastatic disease

Abstract Metastatic disease is believed to develop following dissemination of cells to target organs. Inability of this theory to effectively explain certain phenomena such as patterns of metastatic spread, late metastasis formation, different gene patterns between primary cancer and metastasis have brought forward the need for alternative models. Recent discoveries have strengthened the validity of theories supporting a humoral transfer of malignant traits as opposed to migration of malignant cells to explain metastatic disease in cancer patients. In light of this new evidence, we would like to highlight a model that offers a new perspective to explain cancer metastasis. In the system that we theorize, genetic material released by cancer cells would travel, either free or packed in exosomes, through the blood. Target cells located in organs deriving from the same embryological layer might uptake this genetic material due to expression of specific receptors. Interplay with the immune system would determine the fate of these oncofactors and would regulate their ability to circulate in the blood, integrate in the genome and be transcribed. We also hypothesize that the expression of cell membrane receptors such as integrins, to which cancer exosomes ligate might be mediated by inherited or acquired oncosuppressor mutations

Fatal injection of ranitidine: a case report

ABSTRACT: INTRODUCTION: Ranitidine hydrochloride (Zantac(R)), a histamine-2-receptor antagonist, is a widely used medication with an excellent safety record. Anaphylactic reaction to ranitidine is an extremely rare event and a related death has never been described in the literature. CASE PRESENTATION: We present the clinical history, histological and toxicological data of a 51-year-old man with negative anamnesis for allergic events, who died suddenly after the intravenous administration of one phial of Zantac(R) 50 mg prescribed as a routine post-surgical prophylaxis for stress ulcer. CONCLUSION: Although the incidence of anaphylactic reactions related to ranitidine is low, caution needs to be exercised on administration of this drug. In addition, further study is needed to define strategies for the prevention of adverse drug reactions in hospitalized patients

Robot-assisted excision of urachal cyst: case report in a child

Abstract Background The urachus is an embryological structure of the urogenital sinus and allantoid that connects the allantois to the early bladder in fetal life and then remains as the median umbilical ligament connecting the umbilicus to the dome of the bladder. An early laparoscopic procedure could trigger a quiescent urachal remnant to become symptomatic, causing a lesion or infection either during carbon oxide contamination or insufflation or a periumbilical or suprapubic port placement. Case presentation A 15-year-old girl complaining of supra-pubic abdominal pain. About 2 months previously, she had undergone laparoscopic appendectomy for acute appendicitis, and early postoperative period was uneventful. She underwent a robotic-assisted excision of a urachal cyst. Conclusions It has been suggested that early laparoscopic procedures could trigger previously asymptomatic urachal remnants to become symptomatic. Robot-assisted excision of a urachal cyst is a safe, effective alternative to open surgery in children

Ostial plication: a rarely reported cause of sudden death

We report a rare case of ostial plication as a potential cause of sudden death. Very few reports and images are available in the specialized literature regarding this anomaly. Ostial plication may be a source of sudden death or cause of death when no other significant autopsy findings are present

Lentils biodiversity: the characterization of two local landraces

A multi-disciplinary approach was used to characterize two autochthonous lentil landraces from Molise region (Central Italy). Different mature seed populations for each landrace were provided by the Molise Germoplasm Bank at the University of Molise (Pesche, Italy), and analyzed at the morphological and molecular (DNA and protein) levels. Nuclear ISSR markers were used to assess genetic differences, whereas phenotypic variability was detected by biochemical (proteomics) and morphological analyses. The genetic and phenotypic diversity of the two lentil landraces were well assessed in relation to their geographical provenance, supporting further studies to identify landrace markers

Recurrent Subarachnoid Bleeding and Superficial Siderosis in a Patient with Histopathologically Proven Cerebral Amyloid Angiopathy

A 68-year-old man with a history of hypertension presented with recurrent subarachnoid bleeding. Brain MRI showed superficial siderosis, and diagnostic cerebral angiograms did not show any intracranial vascular malformation or arterial aneurism. Post mortem neuropathological examination of the brain was consistent with a diagnosis of cerebral amyloid angiopathy. Clinicians should be aware that cerebral amyloid angiopathy should be considered in patients with unexplained recurrent subarachnoid bleeding, even in cases without familial clustering or transthyretin variant