The new IMGC-02 transportable absolute gravimeter: measurement apparatus and applications in geophysics and volcanology

The research carried out at the Istituto Nazionale di Ricerca Metrologica (formerly Istituto di Metrologia «G. Colonnetti») aiming to develop a transportable ballistic absolute gravimeter ended with a new version of the instrument, called the IMGC-02. It uses laser interferometry to measure the symmetrical free rising and falling motion of a test mass in the gravity field. Providing the same accuracy achieved with previous versions, the instrumental improvements mainly concern size, weight, data processing algorithms and operational simplicity. An uncertainty of 9 μGal (1 μGal=1×10–8 m·s−2) can be achieved within a single observation session, lasting about 12 h, while the time series of several observation sessions show a reproducibility of 4 μGal. At this level, gravity measurements provide useful information in Geophysics and Volcanology. A wide set of dynamic phenomena, i.e. seismicity and volcanic activity, can produce temporal gravity changes, often quite small, with an amplitude ranging from a few to hundreds of microgals. Therefore the IMGC absolute gravimeter has been employed since 1986 in surveying the Italian active volcanoes. A brief history of the gravimeter and the description of the new apparatus, together with the main results of ongoing applications in Geophysics and Volcanology are presented

Evidence of Hepatitis E Virus (HEV) infection in human and pigs in Sardinia, Italy

Introduction. The aim of this study was to determine the seroprevalence of anti-HEV antibodies in humans sera and to study HEV prevalence in swine from different Sardinian farms, testing viral HEV-RNA in bile samples. Methods. In the first six months of 2008, 532 subjects of whom 402 blood donors and 130 workers at zoonotic risk, were enrolled. Anti-HEV were determined with an enzyme linked immunosorbent assay (ELISA). In positive subjects, RNA was extracted and tested by RT-Nested-PCR. From July 2006 to March 2007, 95 bile samples were collected from randomly selected pigs. RNA was extracted from 250 ?l of bile and tested by RT-Nested-PCR. Results. The overall prevalence of anti-HEV antibodies was 4.3%; 5.0% among blood donors and 2.3% among workers at zoonotic risk, with no statistically significant differences between sex, age classes and occupation. The search for HEV-RNA in the subjects positive for antibodies, gave negative results. HEV genome was detected in 6 of the 95 swine bile samples tested. Sequences were clustered within the genotype 3 and are edited on GenBank under accession number: from FJ850960 to FJ850962 and from FJ883000 to FJ883002. Discussion. The overall prevalence of anti-HEV shows that the virus circulates without giving origin to cases of acute hepatitis. The low prevalence value found in workers at zoonotic risk do not apparently support the hypothesis of professional risk. In this study, HEV-RNA was isolated from pigs in Sardinia for the first time confirming the role of swine as HEV reservoir and the possibility of virus transmission to humans

The new IMGC-02 transportable absolute gravimeter: measurement apparatus and applications in geophysics and volcanology

The research carried out at the Istituto Nazionale di Ricerca Metrologica (formerly Istituto di Metrologia «G. Colonnetti») aiming to develop a transportable ballistic absolute gravimeter ended with a new version of the instrument, called the IMGC-02. It uses laser interferometry to measure the symmetrical free rising and falling motion of a test mass in the gravity field. Providing the same accuracy achieved with previous versions, the instrumental improvements mainly concern size, weight, data processing algorithms and operational simplicity. An uncertainty of 9 μGal (1 μGal=1×10–8 m·s−2) can be achieved within a single observation session, lasting about 12 h, while the time series of several observation sessions show a reproducibility of 4 μGal. At this level, gravity measurements provide useful information in Geophysics and Volcanology. A wide set of dynamic phenomena, i.e. seismicity and volcanic activity, can produce temporal gravity changes, often quite small, with an amplitude ranging from a few to hundreds of microgals. Therefore the IMGC absolute gravimeter has been employed since 1986 in surveying the Italian active volcanoes. A brief history of the gravimeter and the description of the new apparatus, together with the main results of ongoing applications in Geophysics and Volcanology are presented

Evaluation of Urban Spaces Through the Integration of Universal Design and Microsimulation: The Case Study of the Marina District in Cagliari (Italy)

Ensuring safe, functional, and integrated urban environments requires the identification and organisation of qualitative and quantitative analyses to assess the quality of urban spaces, the perceived well-being and by safety the city users, and the interactions between traffic components (e.g., pedestrians and vehicles). Many techniques based on quantitative and qualitative indicators of urban space and transport mobility are offered in literature and this paper provides a methodological approach to perform a comprehensive evaluation of urban spaces and mobility interactions by calculating an Index of Integrated Road Spaces (IIRS) composed of two indicators: the Universal Design Indicator (IUD) and the Service Level Indicator (ISL).This provides the evaluation of Perceived Road Quality (e.g. crossing; visibility; speed limit; road pavement; services), as well as the measurement of network efficiency (e.g. level of service; queue length; number of stops; delay) and environmental impact (e.g. pollutant emissions). The authors applied the merging of the two theoretical approaches of Universal Design and Transport Microsimulation by considering a real case study coinciding with the Marina district in Cagliari (Italy). Future developments of the research will be characterised by a more in-depth analysis, both in terms of spatial extension and number of indicators, useful for performing scenario analysis. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG

Accessibility and Polarities of Pedestrian Network in University Campuses. A Space Syntax Application

This paper examines the multiple interactions between pedestrian mobility systems and land use planning within the framework of Agenda 2030’s sustainability goals involving the integration of mobility networks with urban planning development (i.e., targets 11.2 and 11.3). The study focuses on suburban university campuses and science parks as significant cases. Specifically, two different campuses and science parks have been selected as case studies, i.e., Parma and Monserrato (metropolitan city of Cagliari), located in peripheral areas and built during the second half of the 20th century. The methodological approach is based on Space Syntax, to analyse the spatial configuration of the pedestrian infrastructure of each campus. First, a segment map reflecting all pedestrian routes on each campus has been created. Then, multiple measures have been calculated using the DepthmapX software, evaluating accessibility and identifying polarities. Subsequently, the strengths and weaknesses of each campus’s pedestrian infrastructure network have been identified and a comparison analysis between the two case studies has been performed to identify common and efficient space conformation characteristics according to the Space Syntax analysis. The study concludes with an analysis of the limitations of the methodology and provides suggestions for further research. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG