223 research outputs found
Experiences and preliminary results of geophysical methods on historical statues
In recent years, geophysical applications have been significantly grown in rock mechanics field due to their versatility and reliability as diagnostic and/or monitoring tools. Since these methodologies are mainly non-invasive, they can be used for the investigation and characterization of the internal structure of historical artworks or for the monitoring of built cultural heritage, where the non-destructive feature is an indispensable prerequisite. Commonly, the artworks material properties are unknown or strongly altered due to time and physical/chemical agents. Moreover, their nature (mineralogic and petrographic) and origin (in terms of places where the material was exploited) is uncertain and difficult to allocate. Among the available geophysical techniques, seismic methods are useful for detecting the thickness or position of weathered layers, for estimating the physical properties of different materials and for providing information about cracking and degree of fracturing. In this paper, we present some experiences and preliminary results of geophysical characterization of two Tritons statues, discovered in the garden of the Royal Palace of Venaria (Piedmont Region, Italy). The statues
were originally part of the Fountain of Hercules, destroyed in the 18th century during the redevelopment works of the Palace. Ultrasonic pulse velocity measurements were performed on each portion of the statues and 3D-imaging of the apparent P-wave velocity were carried out. The performed geophysical investigations were aimed at defining the overall material quality and detecting possible sectors with low resistance properties that might interfere with the coring
operations, necessary for the reassembly of the statues. Results of these surveys were also useful for setting up a 3D-FEM model for simulating the material behaviour through an analysis of the forces and loads involved
Effect of Light-emitting Diode (LED) Light Exposure on Vegetable Oils Oxidation as Related to Storage
Monitoring Chemical Changes of Coffee Beans During Roasting Using Real-time NIR Spectroscopy and Chemometrics
Variations occurring in coffee beans during roasting are ascribable to several chemical-physical phenomena: to quickly track the whole process and to ensure its reproducibility, a process analytical technology (PAT) approach is needed.
In this study, a method combining in-line Fourier transform near-infrared (FT-NIR) spectroscopy and chemometric modelling was investigated to get real-time and practical knowledge about the roasting effects on coffee’s chemical-physical composition. In-line spectra were acquired by inserting a NIR probe into a laboratory coffee roaster, running twenty-four roasting experiments, planned spanning different coffee species (Arabica and Robusta), four roasting temperature settings (TS1–TS4) and times (650–1580 s).
Multivariate curve resolution-alternate least squares (MCR-ALS) was used to model the chemical-physical changes occurring during the roasting process, and information about maximum rate, acceleration and deceleration of the process was obtained, also highlighting potential effects due to the different roasting temperatures and coffee varieties.
The proposed approach provides the groundwork for direct real-time implementation of rapid, non-invasive automated monitoring of the roasting process at industrial scale
NIR and Visible spectroscopies coupled with chemometrics for the evaluation of edible seed oils quality evolution during storage under different illumination conditions
Diffusion-weighted magnetic resonance imaging of thymoma: ability of the Apparent Diffusion Coefficient in predicting the World Health Organization (WHO) classification and the Masaoka-Koga staging system and its prognostic significance on disease-free survival
Age determination and authentication of ceramics: advancements in the thermoluminescence dating laboratory in Torino (Italy)
13Classified as an absolute dating method, thermoluminescence (TL) is a well-established radiation-based technique for the age determination and authentication of ceramic materials. Specifically, this method allows the determination of the time elapsed since kiln firing (or later fire events) by evaluating the luminescent emission of ceramics under heating at high temperatures. This paper provides a comprehensive presentation of the TL laboratory developed over the last decade at the Physics Department of the University of Torino. The laboratory was set up in collaboration with TecnArt S.r.l. and is also currently operating within the cultural heritage network of the National Institute of Nuclear Physics (INFN-CHNet). More than 10 years of experience in the field has resulted in improvements in procedures, with the development of customised alpha- and beta-irradiation systems and the optimisation of sampling approaches and chemical pre-treatment. Thanks to TecnArt S.r.l., the laboratory has been employed for dating and authenticating hundreds of archaeological sites and artworks, some of which are discussed in this work and compared, when possible, with radiocarbon dating.openopenGuidorzi, Laura; Fantino, Fulvio; Durisi, Elisabetta; Ferrero, Marco; Re, Alessandro; Vigorelli, Luisa; Visca, Lorenzo; Gulmini, Monica; Dughera, Giovanni; Giraudo, Giuseppe; Angelici, Debora; Panero, Elisa; Lo Giudice, AlessandroGuidorzi, Laura; Fantino, Fulvio; Durisi, Elisabetta; Ferrero, Marco; Re, Alessandro; Vigorelli, Luisa; Visca, Lorenzo; Gulmini, Monica; Dughera, Giovanni; Giraudo, Giuseppe; Angelici, Debora; Panero, Elisa; Lo Giudice, Alessandr
PO-332 Genomic landscapes, neoantigen profiles and biological impact of MLH1 inactivation in cancer cells
Introduction Alterations in DNA repair pathways are thought to fuel tumour progression. Mismatch Repair (MMR) deficient cancers show peculiar biological features such as an indolent progression and a resolute therapeutic response to checkpoint inhibitors. The genomic and biological bases of the peculiar clinical features are poorly understood. Further progress in this area is limited by the paucity of models to study the impact of MMR genes inactivation at the genomic and biological levels. To address this issue we developed a bioinformatic workflow to monitor the neoantigen repertoire induced by inactivation of the Mlh1 gene (a key player of the MMR machinery), in murine cell lines. Material and methods We inactivated Mlh1 throughout the CRISPR-Cas9 technology in CT26 (colon cancer), PDAC (pancreatic cancer) and TSA (breast cancer) murine cell lines. We performed whole exome sequencing (WES) at different time points and then we quantified the amount of mutations (SNVs and indels). We generated a pipeline that characterises the neoantigen repertoire, starting from annotated alterations and the HLA of specific murine strain. In parallel, we inoculated MMR-proficient and -deficient cells in immuno-compromised and -competent mice and monitored their growth. Results and discussions In all pre-clinical models analysed we found a massive increment in the number of non-synonymous alterations (up to 100% increase respect to basal population) after Mlh1 inactivation. Notably, analysis of MMR deficient mouse cells at different time points showed a renewal of mutational profile and consequently an accumulation of predicted neoantigens. We further characterised the SNVs and frameshifts acquired by Mlh1-knockout cells. In agreement with data in human tumours, the fraction of predicted neoantigens derived from frameshifts was higher than the SNV-derived neoantigens. When injected in immuno-compromised mice the Mlh1-knockout cells and their wild type counterpart showed comparable growth. On the contrary, MMR-deficient cells but not their control counterpart grew poorly in immuno-competent mice and responded promptly to treatment with checkpoint inhibitors. Conclusion We find that Mlh1 gene inactivation drives dynamic neoantigen profiles, which can be monitored with an ad hoc bioinformatic pipeline. These analyses provide mechanistic support to understand why MMR deficient cells engage the immune system of the host, foster immune surveillance and tumour control
Differentiation between Fresh and Thawed Cephalopods Using NIR Spectroscopy and Multivariate Data Analysis
The sale of frozen–thawed fish and fish products, labeled as fresh, is currently one of the most common and insidious commercial food frauds. For this reason, the demand of reliable tools to identify the storage conditions is increasing. The present study was performed on two species, commonly sold in large-scale distribution: Cuttlefish (Sepia officinalis) and musky octopus (Eledone spp.). Fifty fresh cephalopod specimens were analyzed at refrigeration temperature (2 ± 2°C), then frozen at −20°C for 10 days and finally thawed and analyzed again. The performance of three near-infrared (NIR) instruments in identifying storage conditions were compared: The benchtop NIR Multi Purpose Analyzer (MPA) by Bruker, the portable MicroNIR by VIAVI and the handheld NIR SCiO by Consumer Physics. All collected spectra were processed and analyzed with chemometric methods. The SCiO data were also analyzed using the analytical tools available in the online application provided by the manufacturer to evaluate its performance. NIR spectroscopy, coupled with chemometrics, allowed discriminating between fresh and thawed samples with high accuracy: Cuttlefish between 82.3–94.1%, musky octopus between 91.2–97.1%, global model between 86.8–95.6%. Results show how food frauds could be detected directly in the marketplace, through small, ultra-fast and simplified handheld devices, whereas official control laboratories could use benchtop analytical instruments, coupled with chemometric approaches, to develop accurate and validated methods, suitable for regulatory purposes
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