315 research outputs found

    Dynamic and seismic health monitoring of a historic masonry tower

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    The paper presents some results of the continuous dynamic/seismic monitoring program carried out on the tallest historic tower in Mantua, Italy. This project follows an extensive diagnostic investigation aimed at assessing the structural condition of the tower after the Italian earthquakes of May 2012. A simple dynamic monitoring system was installed in the tower to evaluate the dynamic response especially to the expected sequence of far-field earthquakes and to check the possible evolution of the natural frequencies; the response to ambient excitation has been continuously collected in 1-hour records since late December 2012. The paper summarizes the results of the continuous dynamic monitoring for a period of 8 months, highlighting the effect of temperature on automatically identified natural frequencies, the dynamic response to few seismic events and the key role of permanent dynamic monitoring in the diagnosis of the investigated historic building

    One-year dynamic monitoring of a historic tower: damage detection under changing environment

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    The paper summarizes the conceptual development of a vibration-based strategy suitable to the structural health monitoring of ancient masonry towers and exemplifies its application in the continuous dynamic monitoring of the tallest historic tower in Mantua, Italy. The presented approach is based on the installation of low-cost monitoring systems (consisting of few accelerometers and temperature sensors) and on the combined use of automated operational modal analysis, regression models to mitigate the environmental effects on identified natural frequencies and multivariate statistical tools to detect the occurrence of abnormal structural changes. The application of the adopted strategy to 15 months of continuously collected experimental data: (1) highlighted the effect of temperature on the automatically identified natural frequencies; (2) demonstrated the practical feasibility of damage detection methods based on natural frequency shifts; (3) provided a clear evidence of the possible key role of continuous dynamic monitoring in the preventive conservation of historic towers

    One-year dynamic monitoring of a masonry tower

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    The paper presents some results of the continuous dynamic monitoring program carried out on the tallest historic tower in Mantua, Italy. This project follows an extensive diagnostic investigation aimed at assessing the structural condition of the tower after the Italian earthquakes of May 2012. A simple dynamic monitoring system was permanently installed in the upper part of the building and automatic modal identification was performed. The results allow to evaluate the effects of changing temperature on automatically identified natural frequencies, to verify the practical feasibility of damage detection methods based on natural frequencies shifts and provide clear evidence of the possible key role of continuous dynamic monitoring in the preventive conservation of historic towers

    Pre-diagnostic prompt investigation and static monitoring of a historic bell-tower

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    An extensive research program is currently in progress to assess the structural condition of the bell-tower of the Church Santa Maria del Carrobiolo in Monza, Italy and to address the preservation of the historic building. The research program was consequent to the direct survey of the tower, carried out within a wide cataloguing activity of the main religious buildings in Monza and highlighting a weak structural layout of the bell-tower. The paper presents the main results of the investigation program performed to date and including: (a) documentary research, systematic visual inspection on site and experimental evaluation of the fundamental period of the tower, carried out using an industrially engineered microwave interferometer; (b) installation of a static monitoring system aimed at surveying the opening of the main cracks, possibly related to the recent construction of an underground car park in the close neighbourhood of the church; (c) dynamic tests in operational conditions, performed using conventional high-sensitivity accelerometers with the twofold objective of validating a FE model of the tower and implementing the installation of a continuous dynamic monitoring system

    Frequent detection of high human papillomavirus DNA loads in oral potentially malignant disorders

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    Human papillomavirus (HPV) is estimated to be the cause of 40-80% of the squamous cell carcinoma of the oropharynx but only of a small fraction of the oral cavity cancers. The prevalence of oral HPV infection has significantly increased in the last decade, raising concerns about the HPV role in progression of oral potentially malignant disorders (OPMD) toward squamous cell carcinomas. We sought to study HPV infection in patients with oral lesions, and in control individuals, using non-invasive and site-specific oral brushing and sensitive molecular methods. HPV DNA positivity and viral loads were evaluated in relation to patient data and clinical diagnosis. We enrolled 116 individuals attending Dental Clinics: 62 patients with benign oral lesions (e.g. fibromas, papillomatosis, ulcers) or OPMD (e.g. lichen, leukoplakia) and 54 controls. Oral cells were collected with Cytobrush and HPV-DNA detected with quantitative real-time PCR (qPCR) for the more common high-risk (HR) and low-risk (LR) genotypes. HPV detection rate, percentage of HR HPVs and HPV-DNA loads (namely HPV16 and in particular, HPV18) were significantly higher in patients than in controls. Lichen planus cases had the highest HPV positive rate (75.0%), hairy leukoplakia the lowest (33.3%). This study detected unexpectedly high rates of HPV infection in cells of the oral mucosa. The elevated HR HPV loads found in OPMD suggest the effectiveness of qPCR in testing oral lesions. Prospective studies are needed to establish whether elevated viral loads represent a clinically useful marker of the risk of malignant progression

    Surveying, modeling and communication techniques for the documentation of medieval wooden painted ceilings in the Mediterranean area

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    Wooden painted ceilings of the Mediterranean area in the middle age have their origin in the islamic culture and were then spread in the countries under the dominion of the Arabs; some of the surviving ceilings are now located in Sicily and Spain. In the historic centre of Palermo two well preserved medieval ceilings are still surviving; the first, built in the XII century, is located in the Palatine chapel; the second one, built in the XIV century covers the “Sala Magna” in the Steri of Palermo. The research, focused on the ceiling in the Steri, deals with the definition of a process for the integration of surveying techniques (photogrammetry, laser scanning), modelling processes and communication technologies for the documentation of such artefacts. The documentation of painted ceilings requires the strict integration of photographic and 3D metric data; the existing documentation is usually made of documents (drawings, photographs) that keep geometric and metric data separated from the photographic documentation of the paintings. The first stage in this work is therefore addressed to produce a digital document that combines metric and photographic data in a 3D textured model; in the second stage a vocal guide interacting with the 3D model has been developed; such guide, thought as a support to people visiting the Steri, uses a database with historic contents and symbolic interpretation of the painted scenes to answer specific questions and “take” the visitor close to the related paintings

    Validation of a small-size pooling approach targeting hospital surveillance of SARS-CoV-2 infection

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    Recent studies describing the detection of SARS-CoV-2 RNA in pools of 5 to 32 samples reported false negative rates up to 10% for large groups, suggesting that smaller sample pools are a good compromise to increase sample processing capacity while maintaining test reliability. Since 5-sample pools were shown to efficiently detect SARS-CoV-2 RNA in RT-PCR assays, we chose to test and validate this approach using a highthroughput RNA extraction and amplification platform

    Static and dynamic monitoring of a Cultural Heritage bell-tower in Monza, Italy

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    A recent survey carried on the historic complex of Santa Maria del Carrobiolo in Monza (Italy) highlighted that the two sides of the bell-tower are directly supported by the load-bearing walls of the apse and South aisle of the neighboring church. After the discovery of the weak structural arrangement of the building, static and dynamic monitoring systems were installed in the tower to address its preservation. After a brief description of the tower and the results of the preliminary survey, the paper presents selected results of the continuous dynamic monitoring as well as the evidences provided by the static monitoring

    QRouteMe: A Multichannel Information System to Ensure Rich User-Experience in Exhibits and Museums

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    In this article the QRouteMe system is presented. QRouteMe is a multichannel information system built to ensure rich user experiences in exhibits and museums. The system starts from basic information about a particular exhibit or museum while delivering a wide user experience based on different distribution channels. The organization of the systems’ components allow to build different solutions that can be simultaneously delivered on different media. A wide range of media from touch-screen installations to portable devices like smartphones have been used. The used devices can communicate each others to increase the usability and the user experience for the visitors. Another important feature of the system is the definition of an inexpensive auto-localization system based on fiduciary marks distributed all around the building. In this article the system is presented from an architectural and functional point of view. A case study and analysis of experimental results are also provided in a real environment where the system was deployed

    Reduced intraoperative bleeding during transurethral resection of the prostate: Evaluation of finasteride, vascular endothelial growth factor, and CD34

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    Finasteride is an antiandrogen that inhibits 5-α- reductase, an enzyme that converts testosterone to dihydrotestosterone. Finasteride significantly reduces intraoperative bleeding when 10 mg/d is administered for 60 days before transurethral resection of the prostate. Our double-blind, randomized, placebo-controlled study evaluated 200 patients with benign prostatic hyperplasia who underwent transurethral resection of the prostate. We compared a placebo group (n = 100) with a group (n = 100) administered 5 mg of finasteride twice a day for 8 weeks. We intended to demonstrate the mechanisms and effects of finasteride compared with those of vascular endothelial growth factor, and to evaluate CD34, an immunohistochemical marker of blood vessel density in the prostate. Our results indicated a lower average microvascular density and vascular endothelial growth factor index for hypertrophic prostate in the finasteride group than in the placebo group
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