The ground vibrations induced by a passenger train at the test site of Ledsgaard, Sweden, have been analysed and numerically simulated through a spectral element discretization of the soil. To ...calculate the spatial distribution of loading due to train passage, the train is decoupled from the track, and a suitable series of static forces is applied. The track and the embankment are modeled as a beam on elastic foundation, using analytical solutions for loads moving at constant velocity. The results of both 2D and 3D modelling assumptions are thoroughly discussed, in terms of prediction of track motion and of attenuation of peak ground velocity with distance.
•Thermodynamic analysis of UHP fluid inclusion chemistry and phase equilibria.•Marbles release solute-bearing COHS fluids during UHP Alpine subduction.•Post-entrapment chemical evolution of UHP ...inclusions is reconstructed.•Electrolytic fluid models are consistent with the inferred evolution.
Subduction fluids play a crucial role in regulating long-term chemical cycles. Their characterisation is essential to understand the processes responsible for metasomatism, oxidation and melting of the mantle wedge. Both direct (fluid inclusion studies) and indirect (thermodynamic modelling) approaches to study subduction fluids have reliability issues due to the complexity of the investigated processes. Post-entrapment processes (e.g., solvent loss by diffusion or decrepitation and/or chemical reactions between host mineral and trapped fluid) are likely to modify the chemical fingerprint of ultra-high pressure (UHP) fluid inclusions, while thermodynamic modelling of solute-bearing fluids at UHP conditions is still at the beginning of its application. In this work, we apply and compare data obtained by both approaches for fluid inclusions trapped within UHP clinopyroxene from a chemically simple Ol-Cpx-Dol-Cal marble (Brossasco-Isasca Unit, Dora-Maira Massif, Western Italian Alps). Classical molecular-fluid thermodynamics is adequate to qualitatively describe the post-entrapment reactions between fluid inclusions and host clinopyroxene. However, an electrolytic fluid model is necessary to describe the chemical composition of the solute-bearing aqueous fluids at the peak metamorphic condition (H2O: 96.30 mol%/88.49 wt%; solutes: 3.61 mol%/11.34 wt%/2.08 mol/kg; other volatiles: 0.09 mol%/0.17 wt%) generated by progressive rock dissolution. Comparison of the model fluid composition with that inferred from the analysis of fluid inclusions clarifies the types and the extent of post-trapping chemical modification of the UHP fluid inclusions. Our data reveal that the fluid-host reactions carry up to 42 mol% of host clinopyroxene component in the fluid inclusion bulk composition, whereas the fluid inclusion decrepitation and the water diffusion in the host clinopyroxene (through dislocations and/or micro-fractures) cause an H2O loss ranging from 18 mol% to 99 mol%. Applying these approaches, we demonstrate that the most relevant post-entrapment process is H2O loss. We also demonstrate that some fluid inclusions did not experience post-entrapment fluid-host modification and, thus, preserve the original fluid geochemistry.
This paper presents REAL (Remotely Accessible Laboratory), a virtual laboratory accessible through the Internet. The objective of REAL is to provide remote access to a mobile robots infrastructure. ...REAL has been implemented as a new generation telecommunication service, not as a commonplace World Wide Web (WWW) application. As such, it employs a sophisticated access framework, a communication infrastructure able to support multimedia flows, and a component-based software construction. The architecture of REAL relies on open standards, such as WWW and its related technologies (HTTP, HTML, XML, Java, etc.) and a common object request broker architecture (CORBA).
This paper presents the Remotely Accessible Laboratory (REAL), a virtual laboratory accessible through the Internet. REAL allows a remote user to manipulate a mobile robot in a mode of interaction ...suitable to his or her level of expertise. A basic mode of interaction, dedicated to users with limited knowledge of robotics, supports interaction via teleoperation. In a more advanced level of interaction, expert users can plan and execute complex robotics experiments that exploit the full capabilities of the robot. In this mode of interaction, experiments in the field of autonomous navigation, environmental mapping, sensor fusion, mission planning, and robot control can be performed. Finally, a third mode of interaction allows a set of trainees to follow the interactions conducted by an instructor. The architecture of REAL departs from the commonplace World Wide Web applications, since it employs a sophisticated software architecture based on software components. This architecture presents a high degree of reusability that future developments in the field of Internet robots and virtual laboratories can take advantage of.
We conducted a randomized trial comparing expectant management versus immunotherapy with paternal leukocytes to improve obstetric outcome in women with unexplained recurrent abortion. Eligible for ...the study were women with unexplained recurrent abortion (three or more miscarriages and no live birth), negative findings of immunological screening and no inhibition of the mixed lymphocyte culture. These women were seen for the first time between October 1988 and March 1991 in a network of obstetric departments in Northern Italy. Subjects positive for HLA DR3 or with a partner positive for hepatitis virus B antigen were not eligible. A total of 44 women entered the study. Patients were randomly allocated to immunotherapy (22 women) or expectant management (22 women). Women allocated to immunotherapy were given 200 x 10(6) purified paternal lymphocytes before pregnancy. Median follow-up was 24 months (range 10-39) in the immunotherapy group and 25 months (range 11-38) in the expectant management group. Out of the 22 women randomized to immunotherapy, 16 became pregnant and the corresponding value was 14 in the expectant management group. Spontaneous abortion occurred in six out of the 16 pregnancies observed in the treated women. Among the 14 pregnancies observed in the expectant management group, two aborted and one late fetal death occurred. The cumulative proportions of women who became pregnant over 4 years were 37 and 45% in the immunotherapy and expectant management groups respectively; this difference was not significant. No adverse effect was observed in treated women.
Abstract With the rapid expansion in the nanotechnology industry, it is essential that the safety of engineered nanomaterials and the factors that influence their associated hazards are understood. A ...vital area governing regulatory health risk assessment is genotoxicology (the study of genetic aberrations following exposure to test agents), as DNA damage may initiate and promote carcinogenesis, or impact fertility. Of late, considerable attention has been given to the toxicity of engineered nanomaterials, but the importance of their genotoxic potential on human health has been largely overlooked. This comprehensive review focuses on the reported abilities of metal nanoparticles, metal-oxide nanoparticles, quantum dots, fullerenes, and fibrous nanomaterials, to damage or interact with DNA, and their ecogenotoxicity is also considered. Many of the engineered nanomaterials assessed were found to cause genotoxic responses, such as chromosomal fragmentation, DNA strand breakages, point mutations, oxidative DNA adducts and alterations in gene expression profiles. However, there are clear inconsistencies in the literature and it is difficult to draw conclusions on the physico-chemical features of nanomaterials that promote genotoxicity, largely due to study design. Hence, areas that require that further attention are highlighted and recommendations to improve our understanding of the genotoxic potential of engineered nanomaterials are addressed.
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