Developing and Testing High-Performance SHM Sensors Mounting Low-Noise MEMS Accelerometers.

Recently, there has been increased interest in adopting novel sensing technologies for continuously monitoring structural systems. In this respect, micro-electrical mechanical system (MEMS) sensors are widely used in several applications, including structural health monitoring (SHM), in which accelerometric samples are acquired to perform modal analysis. Thanks to their significantly lower cost, ease of installation in the structure, and lower power consumption, they enable extensive, pervasive, and battery-less monitoring systems. This paper presents an innovative high-performance device for SHM applications, based on a low-noise triaxial MEMS accelerometer, providing a guideline and insightful results about the opportunities and capabilities of these devices. Sensor nodes have been designed, developed, and calibrated to meet structural vibration monitoring and modal identification requirements. These components include a protocol for reliable command dissemination through network and data collection, and improvements to software components for data pipelining, jitter control, and high-frequency sampling. Devices were tested in the lab using shaker excitation. Results demonstrate that MEMS-based accelerometers are a feasible solution to replace expensive piezo-based accelerometers. Deploying MEMS is promising to minimize sensor node energy consumption. Time and frequency domain analyses show that MEMS can correctly detect modal frequencies, which are useful parameters for damage detection. The acquired data from the test bed were used to examine the functioning of the network, data transmission, and data quality. The proposed architecture has been successfully deployed in a real case study to monitor the structural health of the Marcus Aurelius Exedra Hall within the Capitoline Museum of Rome. The performance robustness was demonstrated, and the results showed that the wired sensor network provides dense and accurate vibration data for structural continuous monitoring.

What Can 5G Do for Public Safety? Structural Health Monitoring and Earthquake Early Warning Scenarios.

The 5th generation of mobile networks has come to the market bringing the promise of disruptive performances as low latency, availability and reliability, imposing the development of the so-called "killer applications". This contribution presents a 5G use case in the context of Structural Health Monitoring which guarantees an unprecedented level of reliability when exploited for public safety purposes as Earthquake Early Warning. The interest on this topic is at first justified through a deep market analysis, and subsequently declined in terms of public safety benefits. A specific sensor board, guaranteeing real-time processing and 5G connectivity, is presented as the foundation on which the architecture of the network is designed and developed. Advantages of 5G-enabled urban safety are then discussed and proven in the experimentation results, showing that the proposed architecture guarantees lower latency delays and overcome the impairments of cloud solutions especially in terms of delays variability.

Calvarial tuberculosis as the initial presentation of AIDS.

A rare case of a young immunocompromised patient with calvarial tuberculosis as the first symptom of human immunodeficiency virus-1 positivity is presented and the pertinent literature is reviewed.

Molecular epidemiology and characteristics of Corynebacterium diphtheriae and Corynebacterium ulcerans strains isolated in Italy during the 1990s.

Five cases of diphtheria were reported in Italy between January 1990 and June 2001. Three cases were confirmed microbiologically by the isolation of toxigenic Corynebacterium diphtheriae (two cases) and Corynebacterium ulcerans (one case). Over the same period, 11 cases of non-toxigenic C. diphtheriae infection were reported to the Italian Public Health Institute, from which the causative organism was isolated from a skin infection in one case and from the throat in the other ten. Seven of the throat isolates were associated with fever, severe pharyngitis and tonsillitis and were all biotype gravis. Because there are no standardized breakpoints, the antimicrobial sensitivities of C. diphtheriae were determined in accordance with the National Committee for Clinical Laboratory Standards guidelines for Streptococcus spp. other than Streptococcus pneumoniae. MICs for penicillin ranged between 0.125 and 0.250 mg l(-1) and 7 out of 11 strains had a minimal bactericidal concentration (MBC)/MIC ratio >or= 32. All strains were sensitive to clindamycin (MIC