A match coefficient approach for damage imaging in structural components by ultrasonic synthetic aperture focus

Ultrasonic Synthetic Aperture Focus (SAF) techniques are commonly used to image structural defects. In this paper, a variation of SAF based on ideas borrowed from Matched Field Processing (MFP) is evaluated to reduce artifacts and sidelobes of the resulting images. In particular, instead of considering the full RF ultrasonic waveforms for the SAF time backpropagation, only selected features from the waveforms are utilized to form a “data vector” and a “replica” (expected) vector of MFP. These vectors are adaptive for the pair of transmitter-receiver and the focus point. The image is created as a matched filter between these two vectors. Experimental results are shown for an isotropic and homogenous metallic plate with simulated defects, probed by six piezoelectric patches used as receivers or transmitters

Peptidergic receptors

The term neuropeptides refers to a relatively large number of biologically active molecules localized to discrete cell populations of nervous system, including autonomic ganglion neurons and their effector cells. Different combinations of transmitters and peptides are found in ganglionic cells of the autonomic system which comprise a functional “chemical code” for neurons subserving specific actions. Generally, peptidergic receptors are G-protein coupled receptors acting through multiple transduction pathways which reflect the pleiotropic actions of peptides. This section represents a current view of the most important actions of peptides and their receptors in the autonomic nervous system and in peripheral organs.L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com

Digital Therapeutics and AI-based Medical Devices: A Guidance for Safety and Compliance in Europe

L'abstract è presente nell'allegato / the abstract is in the attachmen

Microbial regulation of the L cell transcriptome.

L cells are an important class of enteroendocrine cells secreting hormones such as glucagon like peptide-1 and peptide YY that have several metabolic and physiological effects. The gut is home to trillions of bacteria affecting host physiology, but there has been limited understanding about how the microbiota affects gene expression in L cells. Thus, we rederived the reporter mouse strain, GLU-Venus expressing yellow fluorescent protein under the control of the proglucagon gene, as germ-free (GF). Lpos cells from ileum and colon of GF and conventionally raised (CONV-R) GLU-Venus mice were isolated and subjected to transcriptomic profiling. We observed that the microbiota exerted major effects on ileal L cells. Gene Ontology enrichment analysis revealed that microbiota suppressed biological processes related to vesicle localization and synaptic vesicle cycling in Lpos cells from ileum. This finding was corroborated by electron microscopy of Lpos cells showing reduced numbers of vesicles as well as by demonstrating decreased intracellular GLP-1 content in primary cultures from ileum of CONV-R compared with GF GLU-Venus mice. By analysing Lpos cells following colonization of GF mice we observed that the greatest transcriptional regulation was evident within 1 day of colonization. Thus, the microbiota has a rapid and pronounced effect on the L cell transcriptome, predominantly in the ileum

Methods for preclinical validation of software as a medical device

Software as a medical device is subject to dedicated regulatory requirements before it can be used on human beings. The certification process in Europe requires that sufficient data on clinical benefits are available before the device is CE marked. This position paper describes our proposal of a risk-based approach to technical and preclinical validation of software as medical devices. This approach ensures that all technical solutions for safety are implemented in the software and that all information for safe use is consistent before the software can be made available to patients. This approach is compliant to the main international standards ISO 13485 on quality systems and ISO 14971 on risk management and therefore ensures regulatory compliance as well as patient protection. This integrated approach allows the designers of the software to integrate regulatory and safety testing in the technical testing of the candidate release version of the device. This approach ensures patient safety and regulatory compliance at the same time as technical functionality

The role of substance P in secondary pathophysiology after traumatic brain injury

It has recently been shown that substance P (SP) plays a major role in the secondary injury process following traumatic brain injury (TBI), particularly with respect to neuroinflammation, increased blood-brain barrier (BBB) permeability, and edema formation. Edema formation is associated with the development of increased intracranial pressure (ICP) that has been widely associated with increased mortality and morbidity after neurotrauma. However, a pharmacological intervention to specifically reduce ICP is yet to be developed, with current interventions limited to osmotic therapy rather than addressing the cause of increased ICP. Given that previous publications have shown that SP, NK1 receptor antagonists reduce edema after TBI, more recent studies have examined whether these compounds might also reduce ICP and improve brain oxygenation after TBI. We discuss the results of these studies, which demonstrate that NK1 antagonists reduce posttraumatic ICP to near normal levels within 4 h of drug administration, as well as restoring brain oxygenation to near normal levels in the same time frame. The improvements in these parameters occurred in association with an improvement in BBB integrity to serum proteins, suggesting that SP-mediated increases in vascular permeability significantly contribute to the development of increased ICP after acute brain injury. NK1 antagonists may therefore provide a novel, mechanistically targeted approach to the management of increased ICP.Robert Vink, Levon Gabrielian and Emma Thornto

A Proposal For COVID-19 Applications Enabling Extensive Epidemiological Studies

During the next phase of COVID-19 outbreak, mobile applications could be the most used and proposed technical solution for monitoring and tracking, by acquiring data from subgroups of the population. A possible problem could be data fragmentation, which could lead to three harmful effects: i) data could not cover the minimum percentage of the people for monitoring efficacy, ii) it could be heavily biased due to different data collection policies, and iii) the app could not monitor subjects moving across different zones or countries. A common approach could solve these problems, defining requirements for the selection of observed data and technical specifications for the complete interoperability between different solutions. This work aims to integrate the international framework of requirements in order to mitigate the known issues and to suggest a method for clinical data collection that ensures to researchers and public health institution significant and reliable data. First, we propose to identify which data is relevant for COVID-19 monitoring through literature and guidelines review. Then we analysed how the currently available guidelines for COVID-19 monitoring applications drafted by European Union and World Health Organization face the issues listed before. Eventually we proposed the first draft of integration of current guidelines

A novel method for validating multi-classifiers. A case study for ICF-based health status classification

In this paper, we propose a novel method for the validation of a multi-classification model according to the intended use and aim of a device for health status classification and the clinical needs of the practitioners involved