Orbital anomaly reconstruction using deep symbolic regression

This work explores the combination of Sparse and Symbolic Regression, here called Deep Symbolic Regression, for the autonomous reconstruction of orbital anomalies. Orbital anomalies are detectable deviations from the state of an object that can be predicted from the propagation of some observable initial conditions. We contemplate anomalies that can derive from unmodelled natural phenomena or from intentional and unintentional orbital manoeuvres: an accurate modelling of atmospheric density fluctuations, for example, allows informing the space weather. Leveraging the powerful modelling capacity of symbolic regression and the sparse representability of dynamical systems in orbital mechanics , the proposed approach allows one to generate a symbolic representation of orbital anomalies from state observations only. In other words, we use sparse measurements of position and velocity, in general associated with uncertainty, to derive a symbolic representation of the unmodelled part of the dynamics that can explain the deviations of the propagated states. The advantage of such an approach, compared to more traditional filtering techniques, is twofold: it provides an explicit analytical representation of the phenomenon causing the anomaly and it provides a better long term prediction of the dynamics of the object under consideration. The use of Deep Symbolic Regression outdoes more traditional Genetic Programming-based approaches in that it is less prone to overfitting and far less computationally expensive. The explicit dependence, with respect to time, of the symbolic representation, allows one to indirectly model the evolution of unobservable states, whose behaviour can be later inferred from the analysis of the estimated equation itself. The proposed approach yields solutions that are robust against measurement noise: its estimation can be integrated into the derivation of the missing part of the dynamics. The performance of the Deep Symbolic Regression will be assessed against a number of case studies, with a focus on the interpretability of the obtained solutions, demonstrating the performance of this new tracking data-based algorithm

Experimental study on the physical-mechanical durability of innovative hemp-based composites for the building industry

For reducing the environmental impact of the building sector, novel sustainable composites have recently been developed, by bonding hemp hurds with a new hybrid organic-inorganic binder. These composites, designed as substitutes for traditional insulating materials or as substitutes for formaldehyde-bonded wood particle boards, exhibit very promising thermal, physical and mechanical properties. To ensure that the panel performance is maintained during the building operation phase, durability needs to be specifically evaluated as well. Therefore, in this study three composite types with low, medium and high density (LD, MD and HD, respectively) were subjected to accelerated ageing and the alterations in their physical-mechanical properties were evaluated. Composite resistance to accelerated ageing is strongly correlated with bulk density. HD composites, the only ones actually designed to be directly exposed to rainfall, exhibited almost negligible decreases in mechanical properties and hence a substantially satisfactory behavior. MD and LD composites, designed to provide thermal insulation and hence to be sheltered by HD panels, were affected to a larger extent by accelerated ageing, which however was definitely more severe than the real exposure conditions of the composites during their service life. Further studies are currently in progress to optimize the composites formulation and physical-mechanical durability

Paleo‐thermal constraints on the origin of native diagenetic sulfur in the Messinian evaporites : The Northern Apennines foreland basin case study (Italy)

This work has benefited from the equipment and frame-work of the COMP- HUB Initiative (University of Parma), funded by the Department of Excellence programme of the Italian Ministry for Education, University and Research (MIUR, 2018- 2022). This work has benefited from University of Roma Tre MIUR funds for the Department of Excellence. This work has benefited from the University of Parma FIL2016- 2018 responsible Professor Marco Roveri, University of Parma FIL2016- 2018 responsible Professor Vinicio Manzi, MIUR PhD scholarship 2016- 2019. Platte River Associates, Inc is kindly acknowledged for providing BasinMod2D® software for research purposes. Massimo Rossi (ENI S.p.A., Milano, Italy) is kindly acknowledged for his review of the manuscriptPeer reviewedPublisher PD

Intra-Messinian truncation surface in the Levant Basin explained by subaqueous dissolution

The Messinian salinity crisis (MSC) is an extreme event in Earth history during which a salt giant (>1 × 106 km3) accumulated on the Mediterranean seafloor within ~640 k.y. Erosional unconformities extending from the continental margins into the deep basins are key features for reconstructing the MSC; however, the nature of the erosional processes and their subaerial versus subaqueous origin are highly controversial. This study focuses on the top erosion surface (TES) in the deep Levant Basin, which is notably flat, truncating a basinward-tilted Messinian evaporitic succession. Based on high-resolution seismic surveys and wireline logs, we show that (1) the TES is actually an intra-Messinian truncation surface (IMTS) located ~100 m below the Messinian-Zanclean boundary; (2) the topmost, post-truncation Messinian unit is very different from the underlying salt deposits and consists mostly of shale, sand, and anhydrite; and (3) the flat IMTS is a dissolution surface related to significant dilution and stratification of the water column during the transition from stage 2 to stage 3 of the MSC. Dissolution occurred upslope where salt rocks at the seabed were exposed to the upper diluted brine, while downslope, submerged in the deeper halite-saturated layer, the salt rocks were preserved. The model, which requires a stratified water column, is inconsistent with a complete desiccation of the eastern Mediterranean Sea

The Messinian salinity crisis: open problems and possible implications for Mediterranean petroleum systems

Abstract: A general agreement on what actually happened during the Messinian salinity crisis (MSC) has been reached in the minds of most geologists but, in the deepest settings of the Mediterranean Basin, the picture is still far from being finalized and several different scenarios for the crisis have been proposed, with different significant implications for hydrocarbon exploration. The currently accepted MSC paradigm of the ‘shallow-water deep-basin’ model, which implies high-amplitude sea-level oscillations (> 1500 m) of the Mediterranean up to its desiccation, is usually considered as fact. As a consequence, it is on this model that the implications of the MSC events on the Mediterranean petroleum systems are commonly based. In fact, an alternative, deep-water, non-desiccated scenario of the MSC is possible: it (i) implies the permanence of a large water body in the Mediterranean throughout the entire Messinian salinity crisis, but with strongly reduced Atlantic connections; and (ii) envisages a genetic link between Messinian erosion of the Mediterranean margins and deep brine development. In this work, we focus on the strong implications of an assessment of the petroleum systems of the Mediterranean and adjoining areas (e.g. the Black Sea Basin) that can be based on such a non-desiccated MSC scenario. In particular, the near-full basin model delivers a more realistic definition of Messinian source-rock generation and distribution, as well as of the magnitude of water-unloading processes and their effects on hydrocarbon accumulation

Strontium and oxygen isotopes as indicators of Longobards mobility in Italy: an investigation at Povegliano Veronese

The arrival of the Longobards in Northern Italy in 568 CE marked a period of renewed political stability in the Peninsula after the collapse of the Western Roman Empire. The trajectory of the spread of Longobards in Italy across the Alps and into the South is known from many literary sources. However, their mobility and residence patterns at a population level remain to be fully understood. Here we present a multi-isotopic analysis (87Sr/86Sr and 18O/16O) of 39 humans and 14 animals buried at the Longobard necropolis of Povegliano Veronese (VR, Italy; 6th—8th century CE), to address mode and tempo of the spread of this population in the Peninsula. The geographical location of Povegliano Veronese plays a key role: the site lies along the Via Postumia, which was one of the main ancient Roman roads of Northern Italy, representing an important route in post-classical Italy. The integration of isotopic data with the archaeological evidence allowed us to determine the presence of individuals from at least three different regions of origin, building a diachronic map of the dynamics of mobility of this group in northern Italy

The effect of marathon on mRNA expression of anti-apoptotic and pro-apoptotic proteins and sirtuins family in male recreational long-distance runners

<p>Abstract</p> <p>Background</p> <p>A large body of evidence shows that a single bout of strenuous exercise induces oxidative stress in circulating human lymphocytes leading to lipid peroxidation, DNA damage, mitochondrial perturbations, and protein oxidation.</p> <p>In our research, we investigated the effect of physical load on the extent of apoptosis in primary cells derived from blood samples of sixteen healthy amateur runners after marathon (a.m.).</p> <p>Results</p> <p>Blood samples were collected from ten healthy amateur runners peripheral blood mononuclear cells (PBMCs) were isolated from whole blood and bcl-2, bax, heat shock protein (HSP)70, Cu-Zn superoxide dismutase (SOD), Mn-SOD, inducible nitric oxide synthase (i-NOS), SIRT1, SIRT3 and SIRT4 (Sirtuins) RNA levels were determined by Northern Blot analysis. Strenuous physical load significantly increased HSP70, HSP32, Mn-SOD, Cu-Zn SOD, iNOS, GADD45, bcl-2, forkhead box O (FOXO3A) and SIRT1 expression after the marathon, while decreasing bax, SIRT3 and SIRT4 expression (P < 0.0001).</p> <p>Conclusion</p> <p>These data suggest that the physiological load imposed in amateur runners during marathon attenuates the extent of apoptosis and may interfere with sirtuin expression.</p

Strontium and oxygen isotopes as indicators of Longobards mobility in Italy. An investigation at Povegliano Veronese

The arrival of the Longobards in Northern Italy in 568 CE marked a period of renewed political stability in the peninsula after the collapse of the Western Roman empire. the trajectory of the spread of Longobards in Italy across the Alps and into the South is known from many literary sources. However, their mobility and residence patterns at a population level remain to be fully understood. Here we present a multi-isotopic analysis (87Sr/86Sr and 18o/16O) of 39 humans and 14 animals buried at the Longobard necropolis of Povegliano Veronese (VR, Italy; 6th—8th century CE), to address mode and tempo of the spread of this population in the peninsula. the geographical location of povegliano Veronese plays a key role: the site lies along the Via Postumia, which was one of the main ancient Roman roads of Northern Italy, representing an important route in post-classical Italy. The integration of isotopic data with the archaeological evidence allowed us to determine the presence of individuals from at least three different regions of origin, building a diachronic map of the dynamics of mobility of this group in northern Italy

The onset of the Messinian salinity crisis in the deep Eastern Mediterranean basin

Astronomical tuning of the Messinian pre-salt succession in the Levant Basin allows for the first time the reconstruction of a detailed chronology of the Messinian salinity crisis (MSC) events in deep setting and their correlation with marginal records that supports the CIESM (2008) 3-stage model. Our main conclusions are (1) MSC events were synchronous across marginal and deep basins, (2) MSC onset in deep basins occurred at 5.97 Ma, (3) only foraminifera-barren, evaporite-free shales accumulated in deep settings between 5.97 and 5.60 Ma, (4) deep evaporites (anhydrite and halite) deposition started later, at 5.60 Ma and (5) new and published 87Sr/86Sr data indicate that during all stages, evaporites precipitated from the same water body in all the Mediterranean sub-basins. The wide synchrony of events and 87Sr/86Sr homogeneity implies inter-sub-basin connection during the whole MSC and is not compatible with large sea-level fall and desiccation of the Mediterranean

The FXR agonist obeticholic acid inhibits the cancerogenic potential of human cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive cancer with high resistance to chemotherapeutics. CCA is enriched in cancer stem cells, which correlate with aggressiveness and prognosis. FXR, a member of the metabolic nuclear receptor family, is markedly down-regulated in human CCA. Our aim was to evaluate, in primary cultures of human intrahepatic CCA (iCCA), the effects of the FXR agonist obeticholic acid (OCA), a semisynthetic bile acid derivative, on their cancerogenic potential. Primary human iCCA cell cultures were prepared from surgical specimens of mucinous or mixed iCCA subtypes. Increasing concentrations (0–2.5 μM) of OCA were added to culture media and, after 3–10 days, effects on proliferation (MTS assay, cell population doubling time), apoptosis (annexin V-FITC/propidium iodide), cell migration and invasion (wound healing response and Matrigel invasion assay), and cancerogenic potential (spheroid formation, clonogenic assay, colony formation capacity) were evaluated. Results: FXR gene expression was downregulated (RT-qPCR) in iCCA cells vs normal human biliary tree stem cells (p < 0.05) and in mucinous iCCA vs mixed iCCA cells (p < 0.05) but was upregulated by addition of OCA. OCA significantly (p < 0.05) inhibited proliferation of both mucinous and mixed iCCA cells, starting at a concentration as low as 0.05 μM. Also, CDCA (but not UDCA) inhibited cell proliferation, although to a much lower extent than OCA, consistent with its different affinity for FXR. OCA significantly induced apoptosis of both iCCA subtypes and decreased their in vitro cancerogenic potential, as evaluated by impairment of colony and spheroid formation capacity and delayed wound healing and Matrigel invasion. In general, these effects were more evident in mixed than mucinous iCCA cells. When tested together with Gemcitabine and Cisplatin, OCA potentiated the anti-proliferative and pro-apoptotic effects of these chemotherapeutics, but mainly in mixed iCCA cells. OCA abolished the capacity of both mucinous and mixed iCCA cells to form colonies when administered together with Gemcitabine and Cisplatin. In subcutaneous xenografts of mixed iCCA cells, OCA alone or combined with Gemcitabine or Cisplatin markedly reduced the tumor size after 5 weeks of treatment by inducing necrosis of tumor mass and inhibiting cell proliferation. In conclusion, FXR is down-regulated in iCCA cells, and its activation by OCA results in anti-cancerogenic effects against mucinous and mixed iCCA cells, both in vitro and in vivo. The effects of OCA predominated in mixed iCCA cells, consistent with the lower aggressiveness and the higher FXR expression in this CCA subtype. These results, showing the FXR-mediated capacity of OCA to inhibit cholangiocarcinogenesis, represent the basis for testing OCA in clinical trials of CCA patients