15 research outputs found

    A multi-parameter field monitoring system to investigate the dynamics of large earth slides–earth flows in the Northern Apennines, Italy

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    Large earth slides and rocks lides evolving into earth flows are quite widespread in the Northern Italian Apennines. Despite being simply referred to as landslides, many of them are, in fact, large complexes of landslides. They evolved through multiple and/or successive movements, undergoing partial and/or total reactivations. The reactivation of pre-existing landslide bodies is the prevalent mechanism for the known landslide events, as the historical records and the technical reports indicate. Landslide reactivation is, indeed, a relevant topic from the perspective of risk assessment and mitigation. A multi-parameter monitoring system was installed on a large complex of landslides that underwent partial or total reactivations after heavy rainfall events, causing damages to buildings and infrastructures. Two clusters of automatic piezometers—each coupled with an inclinometer—and a time-lapse resistivity deployment were the core of the monitoring system. A weather station, collecting data from subsurface thermometers, and a water content probe completed the system. After the construction of a new geological model of the slope, this study aimed at understanding the possible mechanisms leading to the reactivation of the landslide. This goal was achieved by gaining insights into the process of rainfall infiltration into the landslide deposits, by determining the groundwater flow and evaluating the landslide displacements. The monitoring system captured the processes that took place in the landslide bodies and the bedrock in response to a rainfall event in early February 2017, which followed a dry period of eight months. The recorded data provided indications on the variation of the hydraulic head in the groundwater within the landslide and the bedrock, particularly at the sliding surfaces. The electrical conductivity of the groundwater and the resistivity of the terrain varied across the failure surfaces. In particular, a sudden increase in the electrical conductivity was related to the locations of the main sliding surfaces. The joint analysis of time-lapse resistivity, hydraulic heads, and groundwater electrical conductivity helped identify the locations of weaker levels within the landslide masses, which were confirmed by data from inclinometers. This study improved the knowledge of the hydrogeological behaviour of a complex of landslides in heterogeneous low-permeability media. Moreover, the obtained results contributed to the understanding of the role played by different portions of the landslide complex in the evolution of the movement

    Molecular impact of launch related dynamic vibrations and static hypergravity in planarians

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    Although many examples of simulated and real microgravity demonstrating their profound effect on biological systems are described in literature, few reports deal with hypergravity and vibration effects, the levels of which are severely increased during the launch preceding the desired microgravity period. Here, we used planarians, flatworms that can regenerate any body part in a few days. Planarians are an ideal model to study the impact of launch-related hypergravity and vibration during a regenerative process in a “whole animal” context. Therefore, planarians were subjected to 8.5 minutes of 4 g hypergravity (i.e. a human-rated launch level) in the Large Diameter Centrifuge (LDC) and/or to vibrations (20–2000 Hz, 11.3 Grms) simulating the conditions of a standard rocket launch. The transcriptional levels of genes (erg-1, runt-1, fos, jnk, and yki) related with the early stress response were quantified through qPCR. The results show that early response genes are severely deregulated after static and dynamic loads but more so after a combined exposure of dynamic (vibration) and static (hypergravity) loads, more closely simulating real launch exposure profiles. Importantly, at least four days after the exposure, the transcriptional levels of those genes are still deregulated. Our results highlight the deep impact that short exposures to hypergravity and vibration have in organisms, and thus the implications that space flight launch could have. These phenomena should be taken into account when planning for well-controlled microgravity studies

    Experimental and Numerical Analysis of Linear Plug Nozzles

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    Plug nozzles have received renewed attention in the frame of future launcher developments. Their use appears particularly convenient for Single Stage to Orbit vehicles, because of the overall improvement in performance and also of their possible good integration with the vehicle shape. Nevertheless, a better understanding of the phenomena that take place is necessary, in order to evaluate accurately their behavior. The numerical and experimental analysis of two linear plug nozzle models, performed for different truncation lengths, has allowed to emphasize the critical points of the design. Moreover, the comparisons of numerical and experimental data indicate limitations and expectations for either approach to be used for analyzing their behavior

    A combined targeted/phenotypic approach for the identification of new antiangiogenics agents active on a zebrafish model: From in silico screening to cyclodextrin formulation.

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    A combined targeted/phenotypic approach for the rapid identification of novel antiangiogenics with in vivo efficacy is herein reported. Considering the important role played by the tyrosine kinase c-Src in the regulation of tumour angiogenesis, we submitted our in-house library of c-Src inhibitors to a sequential screening approach: in silico screening on VEGFR2, in vitro screening on HUVEC cells, ADME profiling, formulation and in vivo testing on a zebrafish model. A promising antiangiogenic candidate able to interfere with the vascular growth of a zebrafish model at low micromolar concentration was thus identified

    Viscous and Inviscid Vortex Generation During Startup of Rocket Nozzles

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    A combined targeted/phenotypic approach for the identification of new antiangiogenics agents active on a zebrafish model:from in silico screening to cyclodextrin formulation

    No full text
    A combined targeted/phenotypic approach for the rapid identification of novel antiangiogenics with in vivo efficacy is herein reported. Considering the important role played by the tyrosine kinase c-Src in the regulation of tumour angiogenesis, we submitted our in-house library of c-Src inhibitors to a sequential screening approach: in silico screening on VEGFR2, in vitro screening on HUVEC cells, ADME profiling, formulation and in vivo testing on a zebrafish model. A promising antiangiogenic candidate able to interfere with the vascular growth of a zebrafish model at low micromolar concentration was thus identified
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