202 research outputs found
T.O.F. LASER SCANNER FOR THE SURVEYING OF STATUES: A TEST ON A REAL CASE
Abstract. The contribution regards the surveying of two statues of famous contemporary sculptors that have been placed in the central zone of Cosenza, which has been transformed in an open air museum. To realize a 3-D representation of the museum, different methodologies have been used, based on classical surveying (total stations and GNSS), image data and range data. The increasing performances of the new models of Time Of Flight (T.O.F.) laser scanners allow to build accurate models also for medium-size objects; on the other hand, the recent techniques of 3D modeling enable the processing of large amount of data and the effective removal of noises. Thus, if an extreme accuracy is not required, one can think to use the T.O.F. laser scanner, also for the surveying of statues. For the acquisition of the surfaces of the statues, two different types of laser scanning have been used: the Leica Scan StationC10, based on Time Of Flight, and the Minolta VIVID 300 triangulation scanner. In the paper, the comparison between the results obtained by using the different techniques is described
Dynamic modal identification of telecommunication towers using ground based radar interferometry
This work presents a methodology to monitor the dynamic behaviour of tall metallic towers based on ground-based radar interferometry, and apply it to the case of telecommunication towers. Ground-based radar displacement measurements of metallic towers are acquired without installing any Corner Reflector (CR) on the structure. Each structural element of the tower is identified based on its range distance with respect to the radar. The interferometric processing of a time series of radar profiles is used to measure the vibration frequencies of each structural element and estimate the amplitude of its oscillation. A methodology is described to visualize the results and provide a useful tool for the real-time analysis of the dynamic behaviour of metallic towers
Monitoring of Land Subsidence in Ravenna Municipality Using Integrated SAR - GPS Techniques: Description and First Results
The Emilia Romagna Region (N-E Italy) and in particular the Adriatic Sea coastline of Ravenna, is affected by a noticeable subsidence that started in the 1950s, when the exploitation of on and off-shore methane reservoirs began, along with the pumping of groundwater for industrial uses. In such area the current subsidence rate, even if lower than in the past, reaches the -2 cm/y. Over the years, local Authorities have monitored this phenomenon with different techniques: spirit levelling, GPS surveys and, more recently, Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques, confirming the critical situation of land subsidence risk. In this work, we present the comparison between the results obtained with DInSAR and GPS techniques applied to the study of the land subsidence in the Ravenna territory. With regard to the DInSAR, the Small Baseline Subset (SBAS) and the Coherent Pixel Technique (CPT) techniques have been used. Different SAR datasets have been exploited: ERS-1/2, ENVISAT, TerraSAR-X and Sentinel-1. Some GPS campaigns have been also carried out in a subsidence prone area. 3D vertices have been selected very close to existing persistent scatterers in order to link the GPS measurement results to the SAR ones. GPS data were processed into the International reference system and the comparisons between the coordinates, for the first 6 months of the monitoring, provided results with the same trend of the DInSAR data, even if inside the precision of the method
Structure-based virtual screening of novel natural alkaloid derivatives as potential binders of h-telo and c-myc DNA G-quadruplex conformations
Several ligands can bind to the non-canonical G-quadruplex DNA structures thereby stabilizing them. These molecules can act as effective anticancer agents by stabilizing the telomeric regions of DNA or by regulating oncogene expression. In order to better interact with the quartets of G-quadruplex structures, G-binders are generally characterized by a large aromatic core involved in pi-pi stacking. Some natural flexible cyclic molecules from Traditional Chinese Medicine have shown high binding affinity with G-quadruplex, such as berbamine and many other alkaloids. Using the structural information available on G-quadruplex structures, we performed a high throughput in silico screening of commercially available alkaloid derivative databases by means of a structure-based approach based on docking and molecular dynamics simulations against the human telomeric sequence d[AG(3)(T(2)AG(3))(3)] and the c-myc promoter structure. We identified 69 best hits reporting an improved theoretical binding affinity with respect to the active set. Among them, a berberine derivative, already known to remarkably inhibit telomerase activity, was related to a better theoretical affinity versus c-myc
Multi-Targeting Bioactive Compounds Extracted from Essential Oils as Kinase Inhibitors
Essential oils (EOs) are popular in aromatherapy, a branch of alternative medicine that claims their curative effects. Moreover, several studies reported EOs as potential anti-cancer agents by inducing apoptosis in different cancer cell models. In this study, we have considered EOs as a potential resource of new kinase inhibitors with a polypharmacological profile. On the other hand, computational methods offer the possibility to predict the theoretical activity profile of ligands, discovering dangerous off-targets and/or synergistic effects due to the potential multi-target action. With this aim, we performed a Structure-Based Virtual Screening (SBVS) against X-ray models of several protein kinases selected from the Protein Data Bank (PDB) by using a chemoinformatics database of EOs. By evaluating theoretical binding affinity, 13 molecules were detected among EOs as new potential kinase inhibitors with a multi-target profile. The two compounds with higher percentages in the EOs were studied more in depth by means Induced Fit Docking (IFD) protocol, in order to better predict their binding modes taking into account also structural changes in the receptor. Finally, given its good binding affinity towards five different kinases, cinnamyl cinnamate was biologically tested on different cell lines with the aim to verify the antiproliferative activity. Thus, this work represents a starting point for the optimization of the most promising EOs structure as kinase inhibitors with multi-target feature
SARS-CoV-2 variants and their relevant mutational profiles: update summer 2021
: Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic caused by it, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been undergoing a genetic diversification leading to the emergence of new variants. Nevertheless, a clear definition of the genetic signatures underlying the circulating variants is still missing. Here, we provide a comprehensive insight into mutational profiles characterizing each SARS-CoV-2 variant, focusing on spike mutations known to modulate viral infectivity and/or antigenicity. We focused on variants and on specific relevant mutations reported by GISAID, Nextstrain, Outbreak.info, Pango, and Stanford database websites that were associated with any clinical/diagnostic impact, according to published manuscripts. Furthermore, 1,223,338 full-length high-quality SARS-CoV-2 genome sequences were retrieved from GISAID and used to accurately define the specific mutational patterns in each variant. Finally, mutations were mapped on the three-dimensional structure of the SARS-CoV-2 spike protein to assess their localization in the different spike domains. Overall, this review sheds light and assists in defining the genetic signatures characterizing the currently circulating variants and their clinical relevance. IMPORTANCE Since the emergence of SARS-CoV-2, several recurrent mutations, particularly in the spike protein, arose during human-to-human transmission or spillover events between humans and animals, generating distinct worrisome variants of concern (VOCs) or of interest (VOIs), designated as such due to their clinical and diagnostic impacts. Characterizing these variants and their related mutations is important in tracking SAR-CoV-2 evolution and understanding the efficacy of vaccines and therapeutics based on monoclonal antibodies, convalescent-phase sera, and direct antivirals. Our study provides a comprehensive survey of the mutational profiles characterizing the important SARS-CoV-2 variants, focusing on spike mutations and highlighting other protein mutations
Different evolution of genotypic resistance profiles to emtricitabine versus lamivudine in tenofovir-containing regimens.
BACKGROUND: To investigate genotypic resistance profiles to emtricitabine +
tenofovir (FTC + TDF) in-vivo and in-vitro, and compare them with lamivudine +
tenofovir (3TC + TDF).
METHODS: Three hundred fifty-two HIV-1 B-subtype pol sequences from 42 FTC +
TDF-treated patients, 40 3TC + TDF-treated patients, and 270 patients treated
with 3TC plus another nucleoside reverse transcriptase inhibitor (but not TDF).
All patients never received FTC, 3TC, and TDF in their previous therapeutic
regimen. 3TC/FTC ± TDF resistance was investigated using in vitro selection
experiments and docking simulations.
RESULTS: The M184V mutation is less prevalent in FTC + TDF-treated patients than
in 3TC + TDF-treated, and 3TC-treated/TDF-naive patients (14.3% versus 40.0%, P =
0.01 and 55.6%, P < 0.001). Multivariable analysis shows that factors correlated
with a lower probability of M184V emergence at failure were the use of FTC
compared with 3TC [odds ratio (OR): 0.32 (95% confidence interval (CI): 0.10 to
0.99), P = 0.04], the use of boosted protease inhibitor, and the use of TDF [OR:
0.20 (95% CI: 0.11 to 0.37), P < 0.001, and OR: 0.47 (95%CI: 0.22 to 1.01), P =
0.05, respectively]. In vitro selection experiments and docking analysis show
that other reverse transcriptase (RT) mutations, even localized in RT connection
domain, can be selected by 3TC + TDF or FTC + TDF in M184V absence and can affect
RT affinity for 3TC/FTC and/or TDF.
CONCLUSIONS: Our study shows lower rates of M184V development in FTC + TDF
regimens versus 3TC + TDF and suggests a potential role of boosted protease
inhibitors and TDF in delaying the M184V emergence. Novel RT mutational patterns,
more complex than currently known, can contribute to 3TC, FTC, and TDF
resistance
Reports on Geodesy
The Calabria region has been characterised for a lot of geodynamic phenomena and a complex Geoid. This zone is a very interesting zone for geophysical and geodetic studies. In 1993 has been effectuated a GPS survey. This work shows the quality of the results and a comparison between GPS Geoid and the Italian Gravimetric Geoid performed by Politecnico di Milano.Published1-3753.3. Geodinamica e struttura dell'interno della Terraope
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