Acquisizione Ground Penetrating Radar monocanale e multicanale ad alta risoluzione nei contesti geoarcheologici. Il sito archeologico medievale dell'abbazia di Badia Pozzeveri

L’obiettivo del presente lavoro di tesi consiste nel constatare la capacità del Ground Penetrating Radar (Georadar, GPR) nelle prospezioni geoarcheologiche nell’identificare la presenza di possibili targets riconducibili a strutture d’interesse. Quanto detto è stato raggiunto seguendo un percorso ragionato che ha previsto, in primo luogo, la costruzione di un’efficace sequenza processing del dato, cercando di giustificare sotto un’ottica critica quanto più possibile ogni singolo step e analizzando al contempo quei passaggi spesso non convenzionali nel mondo dell’elaborazione dati GPR. Il dato elaborato è stato quindi sfruttato per la realizzazione di determinati sets di time slices da cui poter osservare la presenza, al variare della profondità temporale, di aree particolarmente riflettive da connettere a probabili strutture antropiche sepolte. Un’ultima fase lavorativa, consequenziale alle precedenti, è infine rivolta all’interpretazione dei radargrammi soggetti a processing mediante l’analisi di un numero campione di profili interessanti i targets individuati. Si è dunque cercato di fornire una probabile origine alle riflessioni maggiormente caratterizzanti i radargrammi. Nello specifico l’oggetto del presente studio ha previsto l’acquisizione, l’elaborazione e la restituzione dei dati rilevati nel corso del progetto di ricerca geoarcheologica svolta nel contesto del sito archeologico dell’abbazia medievale di Badia Pozzeveri (Altopascio – LU) la cui struttura doveva probabilmente occupare un’area più ampia rispetto a quella odierna. L’ipotesi animatrice dell’indagine non sembra essere frutto di semplici speculazioni: una maggiore estensione della struttura ecclesiastica, oggi non più visibile, sembra infatti confermata dalla letteratura in materia ed inoltre la stessa forma in pianta attuale denuncia di per se geometrie anomale nei confronti dei canoni di costruzione delle “colleghe” la cui origine è contemporanea. In particolare due sono state le prospezioni interessanti l’area immediatamente prospiciente la facciata dell’abbazia, ad un primo survey realizzato mediante strumentazione monocanale (avente frequenza nominale pari a 400 MHz) ne è seguito un secondo tramite tecnologia multicanale denominata STREAM X (7 canali, frequenza nominale 200 MHz). La motivazione che ha spinto all’esecuzione di due indagini è da ricondurre alla volontà di confermare quanto deducibile dal primo sondaggio, sfruttando le capacità del GPR multicanale il cui uso consente, in tempi di lavoro ragionevoli, una maggiore copertura della zona interessata. L’elaborazione dei dati è stata realizzata mediante GPR Slice, uno dei software più completi e diffusi per il trattamento dei dati radar. Nei riguardi della tesi in oggetto essa può essere pensata come articolata in parti quali: 1. Inquadramento dell’area indagata 2. Aspetti teorici 3. Breve analisi della strumentazione utilizzata e processing del dato 4. Restituzione del dato attraverso la costruzione e la visualizzazione di time slices 5. Interpretazioni delle principali riflessioni caratterizzanti i radargrammi soggetti ad elaborazione Ad un breve inquadramento dell’area indagata segue quindi una seconda fase che abbraccia ciò che concerne la teoria della fisica delle onde elettromagnetiche e del GPR, includendo inoltre gli aspetti base relativi alle proprietà di un’antenna. Nella terza fase l’attenzione è rivolta in primo luogo sulla strumentazione impiegata e sui parametri d’acquisizione (polarizzazione antenna, frequenza nominale, time window, campionamento spaziale, temporale e risoluzione) ed in secondo luogo al processing del dato. In particolare i dati grezzi, sia mono che multicanale, dopo essere stati sottoposti al pre-processing (detrendizzazione del dato e ricerca di un T0 comune) vengono soggetti ad elaborazione seguendo, per quanto riguarda i dati multicanale, due diversi approcci, un primo sviluppato attraverso gli steps ritenuti necessari ed un secondo caratterizzato da passaggi rientranti in ciò che spesso viene definito over processing. Ciò al fine di valutare se l’applicazione di quest’ultimi al dato possa portare reali benefici nella visualizzazione del target d’interesse. Il primo processing flow prevede dunque quei passaggi comuni nell’elaborazione dati GPR quali: filtraggio passa banda, recupero delle ampiezze e rimozione del background. Il secondo processing flow include gli steps appena citati arrichendo il tutto con: spectral whitening, deconvoluzione spiking, deconvoluzione omomorfa e filtraggio boxcar, passaggi questi spesso non applicati in ambiente georadar per la natura stessa dell’onda elettromagnetica. La fase in questione è stata chiaramente svolta con un’ottica critica per una valutazione dell’effettiva efficacia dei singoli passaggi e di come questi si riflettano nell’elaborazione e nella restituzione del dato. Dopo un’attenta comprensione dei parametri di costruzione, alle tre elaborazioni (monocanale + multicanale minima ed “avanzata”) è seguita la realizzazione di time slices, al fine di poter osservare le variazioni d’ampiezza al variare della profondità e di comprendere, se possibile, gli effettivi vantaggi e svantaggi in termini qualitativi (e di tempistica di lavoro) apportati dalle diverse sequenze d’elaborazione seguite. Un metro di paragone per le time slices è stato in particolare offerto dall’elaborazione eseguita direttamente in sito nell’immediato post acquisizione tramite software GREED. Si tratta comunque di un’elaborazione semplicistica (date anche le ridotte soluzioni offerte dal software) i cui risultati tendono ad offrire geometrie dallo stampo “ideale” il cui compito consiste esclusivamente nel fornire un punto di partenza per lo studio del volume indagato. L’ultima fase include infine l’analisi dei radargrammi, attraverso il quale si cerca di fornire una possibile origine alle riflessioni più evidenti e/o caratteristiche; un aiuto è stato qui fornito dal software il quale prevede la possibilità di effettuare incroci tra i profili e le time slices. L’esito dell’intera operazione può essere reputato più che positivo, l’indagine monocanale sembra infatti rilevare corpi riconducibili a strutture sepolte e ciò sembra essere confermato dall’indagine multicanale (capace per altro d’individuare ampiezze d’onda riflesse non riscontrate dal monocanale); malgrado l’area coinvolta da quest’ultima sia in realtà meno estesa dal settore investigato dal GPR monocanale, evidenti sono i targets comuni individuati. Tali oggetti sembrano dunque confermare l’ipotesi della modifica strutturale dell’abbazia nel corso nei secoli, la quale in passato doveva vantare un’estensione decisamente più ampia rispetto a quella oggi visibile. Inoltre l’applicazione di passaggi del processing non convenzionali al dato grezzo ha permesso di ottenere, al contrario di quanto talvolta accade (overprocessing), immagini migliori rispetto a quelle ottenute attraverso un’elaborazione base

The cold chain and the COVID-19 pandemic: an unusual increase in histamine content in fish samples collected in Southern Italy during lockdown

Objectives We analysed 900 samples of fresh (250) and processed (650) fish products collected in Sicily (Southern Italy) in 2020 during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic (hereafter: COVID-19). Materials and methods The samples were divided temporally based on five phases relating to the various restrictions imposed by the Italian government in this period. The validated method of ultra-high performance liquid chromatography (UHPLC) combined with a diode array detector (DAD) was then employed for the analysis. Results The samples collected during the Phase I lockdown period and after it had ended (Phase II) revealed significant increases in the mean histamine levels: 41.89±87.58 mg/kg -1 and 24.91±76.76 mg/kg -1, respectively. The 11 (1.3% of the total) fresh fish samples that were identified as being non-compliant with EC Reg. 2073/2005 were only found during these two periods. All the processed samples were always compliant. The histamine values decreased as the restrictions eased, achieving a mean value of 11.16±9.3 mgkg -1 (Phase III). Conclusions There was an increase in the incidence of fish samples that were non-compliant with EC Reg. 2073/2005 compared to previous surveillance data. These results provide a first report on the effect of lockdown measures on food safety and the cold chain. Our findings must cause food safety operators to intensify their controls over fresh fish products in such periods to safeguard consumer health. Further studies are required to evaluate whether the same trend would be observed with other food contaminants

Water and lysozyme: Some results from the bending and stretching vibrational modes

The dynamic or glass transition in biomolecules is important to their functioning. Also essential is the transition between the protein native state and the unfolding process. To better understand these transitions, we use Fourier transform infrared spectroscopy to study the vibrational bending and stretching modes of hydrated lysozymes across a wide temperature range. We find that these transitions are triggered by the strong hydrogen bond coupling between the protein and hydration water. More precisely, we demonstrate that in both cases the water properties dominate the evolution of the system. We find that two characteristic temperatures are relevant: in the supercooled regime of confined water, the fragile-to-strong dynamic transition occurs at T[subscript L], and in the stable liquid phase, T* ≈ 315 ± 5 K characterizes the behavior of both isothermal compressibility K[subscript T] (T,P) and the coefficient of thermal expansion a[subscript P] (T,P)

Histamine in Fish Products Randomly Collected in Southern Italy: A 6-Year Study.

In total, 4,615 fresh and processed fish samples collected from 2010 to 2015 were analyzed for histamine by ultrahigh-performance liquid chromatography with diode array detection. Histamine levels were detected in 352 (7.6%) samples, with a maximum of 4,110 mg kg-1 and mean values of 908.9 ± 1,226.79 and 344.01 ± 451.18 mg kg-1 for fresh and processed fish samples, respectively. No histamine levels were found in canned tuna and smoked fish samples in contrast to most of the data reported in the literature. A low percentage (2.79%) of noncompliant samples was found. The highest mean values were found during 2011 and 2015 for fresh and processed fish samples, respectively, showing a significant (P < 0.05) difference between the sampling years. The histamine contents found in fresh fish samples were significantly higher (P < 0.05) than those of processed samples. Most of the positive samples came from street vendors, suggesting the need to improve inspection measures in these commercial categories to ensure fish product safety

Statistical modeling of monthly rainfall variability in Soummam watershed of Algeria, between 1967 and 2018

AbstractThe monthly precipitations obtained during 51 years of measurement in 24 stations of Soummam watershed in Algeria were analyzed to describe rainfall trends and aridity state of the area using statistical modeling. The choice of distribution laws was justified by comparing fitting results of different distributions laws used in literature reviews. Hence, the p values proved that Generalized Extreme Value, Weibull (3) and Logistic the distribution law are more adequate to analyze rainfall frequencies in different part of the watershed. The diagnostic given by Q‐Q plot, P‐P plot and survival regression curve showed the period of wetness and dryness in the northeastern and the southwestern part of the watershed, respectively. Moreover, the study given by the De Martonne index explains the consequences of climate change by a new form of aridity in the watershed between 1994 and 2018.Recommendations for Resource Managers The annual rainfall of Soummam watershed has a moderate and irregular rainfall distribution between 1967 and 2018. Using distribution function on monthly rainfall in each bioclimatic floor to analyze the trend of rainfall frequency gives a spatio‐temporal description of climate in the area. Fitting by Kolmogorov‐Smirnov test allows us to choose generalized extreme value, Weibull (3) and Logistic for modeling monthly rainfall variability in each part of the watershed. The diagnostic obtained by P‐P plot, Q‐Q plot and survival regression curve proved a change of aridity in the northeastern and southwestern part of the watershed between 1994 and 2018

PCSK9 induces a pro-inflammatory response in macrophages

Intraplaque release of inflammatory cytokines from macrophages is implicated in atherogenesis by inducing the proliferation and migration of media smooth muscle cells (SMCs). PCSK9 is present and released by SMCs within the atherosclerotic plaque but its function is still unknown. In the present study, we tested the hypothesis that PCSK9 could elicit a pro-inflammatory effect on macrophages. THP-1-derived macrophages and human primary macrophages were exposed to different concentrations (0.250\u2009\uf7\u20092.5\u2009\ub5g/ml) of human recombinant PCSK9 (hPCSK9). After 24\u2009h incubation with 2.5\u2009\ub5g/ml PCSK9, a significant induction of IL-1\u3b2, IL-6, TNF-\u3b1, CXCL2, and MCP1 mRNA, were observed in both cell types. Co-culture of THP-1 macrophages with HepG2 overexpressing hPCSK9 also showed the induction of TNF-\u3b1 (2.4\u2009\ub1\u20090.5 fold) and IL-1\u3b2 (8.6\u2009\ub1\u20091.8 fold) mRNA in macrophages. The effect of hPCSK9 on TNF-\u3b1 mRNA in murine LDLR-/- bone marrow macrophages (BMM) was significantly impaired as compared to wild-type BMM (4.3\u2009\ub1\u20091.6 fold vs 31.1\u2009\ub1\u20096.1 fold for LDLR-/- and LDLR+/+, respectively). Finally, a positive correlation between PCSK9 and TNF-\u3b1 plasma levels of healthy adult subjects (males 533, females 537) was observed (B\u2009=\u20098.73, 95%CI 7.54\u2009\uf7\u20099.93, p\u2009<\u20090.001). Taken together, the present study provides evidence of a pro-inflammatory action of PCSK9 on macrophages, mainly dependent by the LDLR

Antimicrobial Activity of two Mentha Species Essential Oil and its Dependence on Different Origin and Chemical Diversity

Genus Mentha presents group of plants which are the most studied in family Lamiaceae. Aboveground parts are used for different purposes in pharmacy, food industry or confectionery. Most important is natural product extracted from leaves - essential oil (EO). The aim of presented experiment was to demonstrate different chemotype and compare antibacterial activity of two Mentha species EO. Plant samples were obtained from various environments – from Slovakia and from Italy. Dominant compounds were determined by GC/MS. The results showed high amount of menthol and menthone in tested Slovak peppermint EO. On the other hand, carvone and 1,8-cineole were determinate as dominant compounds in Italian spearmint EO. The antimicrobial activity of the EO was investigated by disc diffusion and broth micro dilution methods. EO was evaluated for their antibacterial activity against 7 microorganisms: Enterobacter cloacae, Salmonella spp., Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes. The determination results of antibacterial activity by agar disk diffusion method ranged from 7 to 14 mm of the growth inhibition zone. MIC of tested mint EO varied from 0.625 to 2.5 μg/mL. In addition, both EO showed relatively the same antibacterial activity against the selected Gram-negative bacteria. However, there is a variation in the antibacterial activity against Gram-positive bacteria

Deformation analysis of ATHENA test filters made of plastic thin films supported by a mesh under differential static pressure

Within ESA Cosmic Vision 2015-2025 Science Program, ATHENA was selected to be a Large-class high energy astrophysics space mission. The observatory will be equipped with two interchangeable focal plane detectors named X-Ray Integral Field Unit (X-IFU) and Wide Field Imager (WFI). In order to optimally exploit the detector sensitivity, X-ray transparent filters are required. Such filters need to be extremely thin to maximize the X-ray transparency, that is, no more than a few tens of nm, still they must be able to sustain the severe stresses experienced during launch. Partially representative test filters were made with a thin polypropylene film, coated with Ti, and supported by a thin highly transparent mesh either in stainless steel or niobium. Differential static pressure experiments were carried out on two filter samples. In addition, the roles of the mesh on the mechanical deformation is studied, adopting a finite element model (FEM). The numerical analysis is compared with experimental results and found in good agreement. The FEM is a promising tool that allows to characterize materials and thicknesses in order to optimize the design

Giant cystic brain metastasis from ovarian papillary serous adenocarcinoma: Case report and review of the literature

Background: Ovarian brain metastases represent a very rare occurrence and without treatment, prognosis is very poor, with a median survival of one month. We present a unique case of a patient affected by a giant cystic intracerebral metastasis (>7 cm) secondary to an ovarian papillary serous adenocarcinoma, along with a review of the literature regarding large cystic ovarian metastases and their management. Case description: A 49-years-old female patient was admitted to our institution because she presented progressive headache and altered consciousness. Brain computed tomography (CT) scan and magnetic resonance imaging (MRI) revealed the presence of a giant left frontal intracerebral cystic lesion. The patient underwent a surgical removal of an ovarian high-grade papillary serous adenocarcinoma three years before. We performed a left frontal craniotomy and microsurgical removal of the brain lesion, achieving a safe macroscopic total resection, thanks to intraoperative neurophysiological monitoring (IONM). The post-operative period was uneventful with a complete recovery. Post-operative brain MRI showed a complete removal of the lesion. Conclusions: The presence of a giant cystic metastasis with symptoms of intracranial hypertension needs a radical and safe surgical removal, along with the management of a multidisciplinary oncologic group. Keywords: Brain metastasis, Ovarian carcinoma, Cystic, Gian