Brief communication. Rain effect on the load of tephra deposits

Accumulation of tephra fallout produced during explosive eruptions can cause roof collapses in areas near the volcano, when the weight of the deposit exceeds some threshold value that depends on the quality of buildings. The additional loading of water that remains trapped in the tephra deposits due to rainfall can contribute to increasing the loading of the deposits on the roofs. Here we propose a simple approach to estimate an upper bound for the contribution of rain to the load of pyroclastic deposits that is useful for hazard assessment purposes. As case study we present an application of the method in the area of Naples, Italy, for a reference eruption from Vesuvius volcano.

3D probability tomography: theoretical developments and applications to high-resolution geophysical prospecting

The theory of the 3D multipole probability tomography method (3D GPT) to image source poles, dipoles, quadrupoles and octopoles, of a geophysical vector or scalar field dataset is developed. A geophysical dataset is assumed to be the response of an aggregation of poles, dipoles, quadrupoles and octopoles. These physical sources are used to reconstruct without a priori assumptions the most probable position and shape of the true geophysical buried sources, by determining the location of their centres and critical points of their boundaries, as corners, wedges and vertices. This theory, then, is adapted to the geoelectrical, gravity and self potential methods. A few synthetic examples using simple geometries and three field examples are discussed in order to demonstrate the notably enhanced resolution power of the new approach. At first, the application to a field example related to a dipole–dipole geoelectrical survey carried out in the archaeological park of Pompei is presented. The survey was finalised to recognize remains of the ancient Roman urban network including roads, squares and buildings, which were buried under the thick pyroclastic cover fallen during the 79 AD Vesuvius eruption. The revealed anomaly structures are ascribed to wellpreserved remnants of some aligned walls of Roman edifices, buried and partially destroyed by the 79 AD Vesuvius pyroclastic fall. Then, a field example related to a gravity survey carried out in the volcanic area of Mount Etna (Sicily, Italy) is presented, aimed at imaging as accurately as possible the differential mass density structure within the first few km of depth inside the volcanic apparatus. An assemblage of vertical prismatic blocks appears to be the most probable gravity model of the Etna apparatus within the first 5 km of depth below sea level. Finally, an experimental SP dataset collected in the Mt. Somma-Vesuvius volcanic district (Naples, Italy) is elaborated in order to define location and shape of the sources of two SP anomalies of opposite sign detected in the northwestern sector of the surveyed area. The modelled sources are interpreted as the polarization state induced by an intense hydrothermal convective flow mechanism within the volcanic apparatus, from the free surface down to about 3 km of depth b.s.l..

Longitudinal relationships between prospective memory, executive functions, and metacognition in young elementary school children

Prospective Memory (PM), executive functions (EF) and metacognition (MC) are relevant cognitive abilities for everyday functioning. They all seem to develop gradually in childhood and appear to be theoretically closely related; however, their empirical links remain unclear, especially in children. As a recent study revealed significant cross-sectional links between PM and EF, and a weaker but close link between PM and MC in 2nd graders (Spiess, Meier, & Roebers, submitted), this study focused on their short-term relationships and on their development. 119 children (MT1 =95 months, SDT1, = 4.8 months) completed the same tasks (one PM, three EF, one MC task) twice with a time-lag of 7 months. T-tests showed significant improvements in all tasks, except in the updating task. Different structural equation models were contrasted (AMOS); the best fitting model revealed that PMT2 was similarly predicted by PMT1 (r = .33) and EFT1 (r = .34). Additionally, EFT1 predicted MCT2 (r = .44), chi2(118, 119) = 128.91, p = .23, TLI = .968, CFI = .978, RMSEA = .028. Results show that PM, EF, and MC develop during childhood and also demonstrate that they are linked not only cross-sectionally, but longitudinally. Findings are discussed in a broader developmental framework.

Trioctahedral micas in xenolithic ejecta from recent volcanism of the Somma-Vesuvius

This study reports the first crystal chemical database resulting from a detailed structural investigation of trioctahedral micas found in xenolithic ejecta produced during the AD 1631, 1872 and 1944 eruptions, three explosive episodes of recent volcanic period of Vesuvius volcano (Southern Italy). Three xenolith types were selected: metamorphic/metasomatic skarns, pyrometamorphic/hydrothermally altered nodules and mafic cumulates. They are related to different magma chemistry and effusive styles: from sub-plinian and most evolved (AD 1631 eruption) to violent strombolian with medium evolution degree (AD 1872 eruption) to vulcanian-effusive, least evolved (AD 1944 eruption) event, respectively. Both xenoliths and micas were investigated employing multiple techniques: the xenoliths were characterized by X-ray fluorescence, inductively-coupled plasma-mass spectrometry, optical microscopy, X-ray powder diffraction, and quantitative energy-dispersive microanalysis; the micas were studied by electron probe microanalysis and single crystal X-ray diffraction. The mica-bearing xenoliths show variable texture and mineralogical assemblage, clearly related to their different origin. Based on the major oxide chemistry, only one xenolithic sample falls in the skarn compositional field from the Somma-Vesuvius literature, some fall close to the skarns and cumulate fields, others plot close to the syenite/foidolite/essexite field. A subgroup of the selected ejecta does not fall or approach any of the compositional fields. Trace and rare earth element patterns show some petrological affinity between studied xenoliths and erupted magmas with typical Eu, Ta and Nb negative anomalies. Strongly depleted patterns were detected for the 1631 metamorphic/metasomatic skarns xenoliths. Three distinct mica groups were distinguished: 1) Mg-, Al-rich, low Ti-bearing, low to moderate F-bearing varieties (1631 xenolith), 2) Al-moderate, F- and Mg-rich, Ti-, Fe-poor varieties (1872 xenolith), and 3) Al-, Ti- and Fe-rich, F-poor phases (1944 xenolith). All the analysed mica crystals are 1M polytypes with the expected space group C2/m. Micas from xenoliths of the 1631 Vesuvius eruption are phlogopites characterized by a combination of low extent of oxy-type and variable extent OH-F-substitutions, as testified by the range of F concentration (from ~ 0.20 to 0.80 apfu). Micas from xenoliths of the 1872 Vesuvius eruption exhibit structural peculiarities typical of fluorophlogopites, i.e. OH-F-substitution is predominant. Micas from the xenolith of the 1944 Vesuvius eruption display features typical of oxy-substituted micas. The variability of the crystal chemical features of the studied micas are consistent with the remarkable variation of their host rocks. Micas from 1631 nodules are related to metasomatic, skarn-type environment, deriving from the metamorphosed wall-rocks hosting the magma reservoir. The fluorophlogopites from the 1872 xenoliths testify for strongly dehydrated environmental conditions compared to those of the 1631 and 1944 hosts. Finally, magma storage condition at depth, associated to a decreasing aH2O may have promoted major oxy-type substitutions in 1944 biotites.

Surface deformation studies of Tenerife Island, Spain from joint GPS-DInSAR observations

This work presents results for the three-dimensional displacement field at Tenerife Island calculated from campaign GPS and ascending and descending ENVISAT DInSAR interferograms. The goal of this work is to provide an example of the flexibility of the technique by fusing together new varieties of geodetic data, and to observe surface deformations and study precursors of potential activity in volcanic regions. Interferometric processing of ENVISAT data was performed with GAMMA software. All possible combinations were used to create interferograms and then stacking was used to increase signal-to-noise ratio. Decorrelated areas were widely observed, particularly for interferograms with large perpendicular baseline and large time span. Tropospheric signal was also observed which significantly complicated the interpretation. Subsidence signal was observed in the NW part of the island and around Mount Teide and agreed in some regions with campaign GPS data. It is expected that the technique will provide better results when more high quality DInSAR and GPS data is available

Insignificance and Minor Architecture

The fragmented condition of our everyday brings us closer to the risks of hyper-expression. Against it two positions unfold to help us face a world that escapes our capacities: familiarity and poetic recognition. In the latter it is crucial the role of the insignificant as dynamic and relational instigator of a conscious threading of reality through the actions of the Poeta Faber and his careful look onto the world. / The production of the common as the material and symbolic fabric of the city, unstable reality in a perpetual becoming, leads us to a new and much needed reconsideration of the public/private division born from the modern state. Immersed in the confusion between public and common, we have not perceived that through the expropriation of the first we have been prepared for the willing surrendering of the second. / From insignificance to rebellion as affirmative going into action related to the idea of minor architecture as common and intensely political production, born from the inside of a society that has no more outsides.

Aircraft trajectory simulator using a three degrees of freedom aircraft point mass model

Aircraft Operators Companies (AOCs) are always willing to keep the cost of a flight as low as possible. These costs could be modelled using a function of the fuel consumption, time of flight and fixed cost (over flight cost, maintenance, etc.). These are strongly dependant on the atmospheric conditions, the presence of winds and the aircraft performance. For this reason, much research effort is being put in the development of numerical and graphical techniques for defining the optimal trajectory. This paper presents a different approach to accommodate AOCs preferences, adding value to their activities, through the development of a tool, called aircraft trajectory simulator. This tool is able to simulate the actual flight of an aircraft with the constraints imposed. The simulator is based on a point mass model of the aircraft. The aim of this paper is to evaluate 3DoF aircraft model errors with BADA data through real data from Flight Data Recorder FDR. Therefore, to validate the proposed simulation tool a comparative analysis of the state variables vector is made between an actual flight and the same flight using the simulator. Finally, an example of a cruise phase is presented, where a conventional levelled flight is compared with a continuous climb flight. The comparison results show the potential benefits of following user-preferred routes for commercial flights.

QKD in standard optical telecommunications networks

To perform Quantum Key Distribution, the mastering of the extremely weak signals carried by the quantum channel is required. Transporting these signals without disturbance is customarily done by isolating the quantum channel from any noise sources using a dedicated physical channel. However, to really profit from this technology, a full integration with conventional network technologies would be highly desirable. Trying to use single photon signals with others that carry an average power many orders of magnitude bigger while sharing as much infrastructure with a conventional network as possible brings obvious problems. The purpose of the present paper is to report our efforts in researching the limits of the integration of QKD in modern optical networks scenarios. We have built a full metropolitan area network testbed comprising a backbone and an access network. The emphasis is put in using as much as possible the same industrial grade technology that is actually used in already installed networks, in order to understand the throughput, limits and cost of deploying QKD in a real network.

On QKD industrialization

During the 25 years of existence of the first protocol for Quantum Key Distribution, much has been said and expected of what came to be termed as Quantum Cryptography. After all this time, much progress has been done but also the reality check and analysis that naturally comes with maturity is underway. A new panorama is emerging, and the way in which the challenges imposed by market requirements are tackled will determine the fate of Quantum Cryptography. The present paper attempts to frame a reasonable view on the issues of the security and market requirements that QKD should achieve to become a marketable technology.

Ellipsometric study of nematic alignment on silicon oxides for display

Vertical Alignment Nematics (VANs) displays are a form of LCDs in which the liquid crystals naturally align vertically to the glass substrates. In spite of their name, the liquid crystal (LC) director is never exactly vertical, rather it always show a small angle with the normal to the sample plane called tilt that may vary throughout the cell bulk. Its values are ultimately determined by the pretilt, defined as the tilt angle on the surfaces in the absence of voltage.

Indice istorico del gran prospetto di Roma, dedicato alla sagra maestà cattolica di Carlo III. re delle Spagne da Giuseppe Vasi ... : ovvero, Itinerario istruttivo per ritrovare con facilità tutte le antiche e moderne magnificenze di Roma : con una breve digressione sopra alcune città e castelli suburbani.

Includes index.

Discorso istorico intorno alla cappella de' signori Minutoli, sotto il titolo di S. Pietro Apostolo e di S. Anastasia Martire dentro il Duomo napoletano /

Signatures: pi²,²pi²,³pi²(-³pi2) A⁸ B-K⁴ L⁶.