10 research outputs found
Damage detection in composite skin stiffener with hybrid PZT-FO SHM system
A hybrid piezoelectric (PZT)/fibre optic diagnostic system has been developed for damage detection in built up composite structures. The hybrid system uses PZT transducers to actuate the structure and fibre optic (FO) sensors to capture the propagating wave. The diagnostic system will then have the advantages of both PZT and FO sensors. The applicability of the system is then tested for detecting an artificial damage at a skin/stiffener interface of a thick composite structure. The response of the FO sensors is then compared to PZT sensors and presented
Practicalities of BVID detection on aerospace-grade CFRP materials with optical fibre sensors
Several reports have recently shown the capability of optical fibre sensors for the detection of barely visible impact damage (BVID) on CFRP laminates, based on changes in the optical signal before and after impact. Although this approach was shown to work well in lab conditions, little attention has been paid so far to its practicality when considering realistic ambient conditions or to the detection range. In this work we attempt to derive BVID detection thresholds for fibre Bragg grating-based sensors, by considering standardized temperature and vibration levels for aerospace applications. To the best of our knowledge this is the first practical threshold assessment for BVID detection on aerospace-grade CFRP for such sensors. We have put our detection thresholds to the test by analysing a total of 24 BVIDs on 12 panels made from 4 different CFRP material systems and derived commendable sizes for the detection range on the different material systems
Smart patch repair with low profile PVDF sensors
Bonded repair of composite structures still remains a major concern for the airworthiness authorities because of the uncertainty about the repair quality. This work, investigates the applicability of conventional Structural Health Monitoring (SHM) techniques for monitoring of bonded repair with ring-shaped low profile sensors. A repaired composite panel has been sensorized with two Ring-Shaped Polyvinylidene fluoride piezopolymer Sensors (RSPS) and a piezoelectric (PZT) transducer. An electromechanical impedance (EMI) and Lamb wave analysis have been carried out to check the sensitivity of these sensors to detect an artificially introduced damage simulating a disbond of the repair. The state of the repair have been successfully monitored and reported by both methods
Clinical Case of the Month. Carcinoid Syndrome Due to a Small Intestine Secreting Tumor with a Cardiopathy
peer reviewedUncommon but classically described, intestinal carcinoid tumors represent a variety of neuroendocrine tumors. Able to secrete amines and hormones, they can produce characteristic symptoms called "carcinoid syndrome". A cardiopathy is sometimes associated with the disease and carries a high risk of mortality and morbidity
Is 5Â days of oral fluoroquinolone enough for acute uncomplicated pyelonephritis? The DTP randomized trial
International audienceThe treatment duration of acute uncomplicated pyelonephritis (AUP) is still under debate. As shortening treatment duration could be a means to reduce antimicrobial resistance, we aimed to establish whether 5 days of antibiotic treatment is non-inferior to 10 days in patients with AUP. We performed an open-label prospective randomized trial comparing 5 days to 10 days of fluoroquinolone treatment for AUP. The inclusion criteria were: female patients aged ≥18 years with clinical signs of urinary tract infection, fever >38 °C, and positive urinalysis. Patients were randomized to either 5 or 10 days of fluoroquinolone treatment. Outcome was cure at day 10 and day 30 after the end of treatment. One hundred patients were randomized and 12 were excluded after randomization. The mean ± standard deviation (SD) age was 31.8 ± 11 years old and the mean ± SD temperature was 38.6 ± 0.7 °C. The main bacterium involved was Escherichia coli (n = 86; 97.7%) and 3 (3.4%) patients had a positive blood culture. In the post-hoc analysis, clinical cure 10 days after the end of the treatment was 28/30 (93.3%) in the 5-day arm and 36/38 (94.7%) in the 10-day arm (p = 1.00). At day 30, the clinical cure rate was 23/23 (100%) in the 5-day arm and 20/20 (100%) in the 10-day arm (p = 1.00). The microbiological cure rate was 20/23 (87.0%) in the 5-day arm and 16/20 (80.0%) in the 10-day arm (p = 1.00). The efficacy of 5 days of fluoroquinolone treatment does not seem different from 10 days of treatment for AUP
Applying genomic data in wildlife monitoring: Development guidelines for genotyping degraded samples with reduced single nucleotide polymorphism panels
peer reviewedThe genomic era has led to an unprecedented increase in the availability of genome-wide data for a broad range of taxa. Wildlife management strives to make use of these vast resources to enable refined genetic assessments that enhance biodiversity conservation. However, as new genomic platforms emerge, problems remain in adapting the usually complex approaches for genotyping of noninvasively collected wildlife samples. Here, we provide practical guidelines for the standardized development of reduced single nucleotide polymorphism (SNP) panels applicable for microfluidic genotyping of degraded DNA samples, such as faeces or hairs. We demonstrate how microfluidic SNP panels can be optimized to efficiently monitor European wildcat (Felis silvestris S.) populations. We show how panels can be set up in a modular fashion to accommodate informative markers for relevant population genetics questions, such as individual identification, hybridization assessment and the detection of population structure. We discuss various aspects regarding the implementation of reduced SNP panels and provide a framework that will allow both molecular ecologists and practitioners to help bridge the gap between genomics and applied wildlife conservation. © 2020 The Authors. Molecular Ecology Resources published by John Wiley & Sons Lt