1,269 research outputs found
Deep-seated gravitational slope deformations in central Sardinia: insights into the geomorphological evolution
In this study, we analyse deep-seated gravitational slope deformations (DSGSDs) in central Sardinia. The area is characterised by plateaus with a prominent limestone scarp overlying metamorphites. A comprehensive mapping of structural, karst, fluvial, and slope morphologies in Pardu and Ulassai valleys is presented herein. The uplift linked to the Plio-Pleistocene tectonic activity leads to high-slope topography, which favours gravitational processes, such as DSGSDs and rock-avalanches. Although DSGSD is a common phenomenon in the relief of the central Mediterranean region, it has never been studied in Sardinia. We describe the kinematic models and geomorphological evolution of DSGSD in Sardinia for the first time. The application of light detection and ranging, high-resolution unmanned aerial vehicle photogrammetry, and geological, structural, and geomorphological surveys enabled a depth morphometric analysis and the development of interpretative three-dimensional models. The geo-structural setting and high relief energy associated with recent upliftment are the major controlling factors of DSGSDs
Fingerprint recognition with embedded presentation attacks detection: are we ready?
The diffusion of fingerprint verification systems for security applications makes it urgent to investigate the embedding of software-based presentation attack detection algorithms (PAD) into such systems. Companies and institutions need to know whether such integration would make the system more “secure” and whether the technology available is ready, and, if so, at what operational working conditions. Despite significant improvements, especially by adopting deep learning approaches to fingerprint PAD, current research did not state much about their effectiveness when embedded in fingerprint verification systems. We believe that the lack of works is explained by the lack of instruments to investigate the problem, that is, modeling the cause-effect relationships when two non-zero error-free systems work together. Accordingly, this paper explores the fusion of PAD into verification systems by proposing a novel investigation instrument: a performance simulator based on the probabilistic modeling of the relationships among the Receiver Operating Characteristics (ROC) of the two individual systems when PAD and verification stages are implemented sequentially. As a matter of fact, this is the most straightforward, flexible, and widespread approach. We carry out simulations on the PAD algorithms’ ROCs submitted to the most recent editions of LivDet (2017-2019), the state-of-the-art NIST Bozorth3, and the top-level Veryfinger 12 matchers. Reported experiments explore significant scenarios to get the conditions under which fingerprint matching with embedded PAD can improve, rather than degrade, the overall personal verification performance
Self-propagating reactions for environmental protection: Treatment of wastes containing asbestos
A thermochemical process based on the occurrence of self-propagating reactions that is able to convert asbestos fibers into harmless, nonfibrous species is proposed. Specifically, a mixture consisting of a waste (containing about 85 wt % of chrysotile), ferric oxide, and magnesium is able, once locally ignited by a thermal source, to generate a self-propagating reaction that travels through the mixture without requiring additional energy. The process is accompanied by a dramatic change in the material from both the chemical and microstructural points of view. In addition, front velocity and maximum combustion temperature decrease as the amount of waste in the starting mixture increases, with the self-propagating character being maintained if the waste content is equal to or below 60 wt %. It is also observed that, when nonasbestos (nontoxic) materials, i.e., sepiolite and glass fibers, are used instead of the hazardous waste, the front velocity, combustion temperature, propagation limits, and apparent activation energies are found to be very similar to those observed in the case of asbestos
Epigenetic mechanisms in oral cancer: new diagnostic and therapeutic strategies
Complexity and heterogeneity are frequently present during the development and progression of carcinogenesis and, in the last 15 years, significant progress made in clinical research underlines the role of
some epigenetic mechanisms. The most important characteristics of the epigenetic concept are that these
events are reversible, not related to modifications in the structure of DNA and may drive fundamental cell
signaling alterations1. Among these systems of communication in normal and pathological conditions,
also microbiome and staminal cells2 seem to be important. These new profiles of pathological communication develop novel diagnostic, prognostic and therapeutic tool
Mitigating Sensor and Acquisition Method-Dependence of Fingerprint Presentation Attack Detection Systems by Exploiting Data from Multiple Devices
The problem of interoperability is still open in fingerprint presentation attack detection (PAD) systems. This involves costs for designers and manufacturers who intend to change sensors of personal recognition systems or design multi-sensor systems, because they need to obtain sensor-specific spoofs and retrain the system. The solutions proposed in the state of the art to mitigate the problem still require data from the target sensor and are therefore not exempt from the problem of obtaining new data. In this paper, we provide insights for the design of PAD systems thanks to an overview of an interoperability analysis on modern systems: hand-crafted, deep-learning-based, and hybrid. We investigated realistic use cases to determine the pros and cons of training with data from multiple sensors compared to training with single sensor data, and drafted the main guidelines to follow for deciding the most convenient PAD design technique depending on the intended use of the fingerprint identification/authentication system
On The Use Of Polyurethane Matrix Carbon Fiber Composites For Strengthening Concrete Structures
Fiber-reinforced polymer (FRP) composite materials have effectively been used in numerous reinforced concrete civil infrastructure strengthening projects. Although a significant body of knowledge has been established for epoxy matrix carbon FRPs and epoxy adhesives, there is still a need to investigate other matrices and adhesive types. One such matrix/adhesive type yet to be heavily researched for infrastructure application is polyurethane. This thesis investigates use of polyurethane matrix carbon fiber composites for strengthening reinforced concrete civil infrastructure. Investigations on mirco- and macro-mechanical composite performance, strengthened member flexural performance, and bond durability under environmental conditioning will be presented. Results indicate that polyurethane carbon composites could potentially be a viable option for strengthening concrete structures
Insight into susceptibility genes associated with bipolar disorder: A systematic review
Objective: Bipolar disorder (BD) is a severe disorder, and it is associated with an increased risk of mortality. About 25% of patients with BD have attempted and 11% have died by suicide. All these characteristics suggest that the disorders within the bipolar spectrum are a crucial public health problem. With the development of molecular genetics in recent decades, it was possible to more easily detect risk genes associated with this disorder. This study aimed at summarizing the findings of systematic reviews and meta-analyses on the topic and assessing the quality of the available evidence. Materials and Methods: PubMed/Medline and Web of Science were searched to identify systematic reviews and meta-analyses published during 2013-2019. Standard methodology was applied to synthesize and assess the retrieved literature. Results: This systematic review identifies a number of potential risk genes associated with bipolar disorder whose mechanism of action has yet to be confirmed. They are divided into several groups: 1) a list of the most significant susceptibility genetic factors associated with BD; 2) the implication of the ZNF804A gene in BD; 3) the role of genes involved in calcium signaling in BD; 4) DNA methylation in BD; 5) BD and risk suicide genes; 6) susceptibility genes for early-onset BD; 7) candidate genes common to both BD and schizophrenia; 8) genes involved in cognitive status in BD cases; 9) genes involved in structural alteration in BD brain tissue; 10) genes involved in lithium response in BD. Conclusions: Future research should concentrate on molecular mechanisms by which genetic variants play a major role in BD. Supplemental research is needed to replicate the applicable results
Does living in previously exposed malaria or warm areas is associated with a lower risk of severe COVID-19 infection in Italy?
Incidence of Covid-19 positivity (21/2/2020-28/3/2020) in provinces of 4 Italian regions whose territory was described as previously exposed to Malaria was compared with those of other provinces of the same regions. The climate of such provinces was compared with the climate of the other provinces in some regions. Previously malarial areas show a lower risk than other provinces of the same regions: Mantua (Lombardy) RR=0.94 (CI95%0.89-0.99); Venice-Rovigo (Veneto) RR=0.61 (CI95%0.58-0.65); Ferrara-Ravenna (Emilia-Romagna) RR=0.37 (CI95%0.35-0.41); CagliariOristano-SouthSardinia (Sardinia) RR=0.25 (0.17-0.31). The maximum temperature in March 2020 in those provinces was higher in mean 1.5° for other provinces. The lower frequency of COVID-19 in the provinces previously exposed to Malaria of four Italian regions does not reveal a causal link. The phenomenon has emerged independently in all the regions investigated. People born between the 1920s and 1950s were those most exposed to malaria years ago and today are the most exposed to the severest forms of COVID-19. A warmer climate seems to be associated with a lower risk of COVID, in line with the evidence highlighted in equatorial states where a lower lethality of the virus has emerged, however this regardless of the presence of Malaria. This may suggest that climate and not Malaria is the real risk factor, though further studies need to determine the role of the association climate / COVID
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