708 research outputs found
Energia e innovazione tra flussi globali e circuiti locali
La tematica energetica \ue8 di fortissima attualit\ue0 e rilevanza sia per questioni antiche (sicurezza nazionale, sviluppo economico) sia per questioni pi\uf9 recenti come il cambiamento climatico. Gran parte delle emissioni che provocano il surriscaldamento del pianeta provengono dalla combustione di fonti fossili. La transizione verso un uso pi\uf9 sostenibile dell\u2019energia sta per\uf2 segnando il passo. Ai buoni risultati ottenuti dall\u2019industria si sommano crescenti consumi civili, in particolare nel settore dei trasporti. I fattori di rallentamento non sono tutti legati alla contingenza economica mondiale, ma riguardano anche fenomeni sociali e istituzionali. Il libro indaga a largo spettro questi fattori, includendo tavole dei flussi energetici per settore, la distribuzione dei consumi su scala urbana e regionale, i sistemi che mirano all\u2019autosufficienza (comunit\ue0 energetiche), i conflitti sulle centrali e le modalit\ue0 giuridiche per regolarli. Ne esce un quadro con luci e ombre. Nonostante l\u2019impegno di molte agenzie e la disponibilit\ue0 di nuovi pacchetti tecnologici, vi \ue8 tuttora una insufficiente consapevolezza del cambiamento climatico, dell\u2019importanza delle nuove fonti di energia, in primis quella solare, e degli effetti re-distributivi su ricchezza e consumi. Una transizione pi\uf9 rapida avverr\ue0 quando questione energetica e coesione sociale saranno contemperate in una prassi ecologica integrata
2nd CapHaz-Net Regional Hazard Workshop: Social capacity building for Alpine hazards
The Alpine Space is a trans-national territory inhabited by 13 million people and comprising the territory of 8 countries, 83 regions and about 6,200 communities. It is characterised by a great variety in terms of natural hazard exposure. Floods, avalanches, debris flows, landslides, forest fires threaten the entire Alpine Space and are triggered by both natural and anthropogenic factors. The work described in this report focuses on this space and aims at bringing together and confronting different perspectives on the theme of social capacity building. It summarises the results of one of the work packages (WP8) of the CapHaz-Net project, which aims at identifying social capacities that contribute to making European societies more resilient to the impacts of natural hazards.
More precisely the work presented here links previous project findings (related both to central topics and specific social capacities) to the practice of alpine hazards management in Europe, underlining potentials for enhancement of resilience both in this region and in Europe as a whole.
This report is based on the preparatory work and the results of the Alpine Regional Hazard Workshop that took place in Gorizia (North Eastern Italy) on 4th and 5th April 2011. The main objectives were to provide an overview of existing institutional frames and the respective policy context at the regional scale, to better understand how social capacity building and preparedness strategies for Alpine hazards work in practice and to foster interdisciplinary and cross country dialogue between scientists and practitioners. This was done by taking into account strengths and weaknesses of existing tools and approaches and by analysing the potential for transferring best practices to different regional and hazard contexts.
To bridge the gap between research and practice both theoretical knowledge and practical experiences were taken into account. The workshop started from a description of the main characteristics of alpine hazards. Then the focus shifted on operational risk management in four different countries of the alpine arch (Austria, Switzerland, Slovenia and Italy) and finally on practices for risk mitigation in two Italian case studies (Vipiteno/Sterzing in the Trentino Alto Adige region and Malborghetto-Valbruna in the Friuli Venezia Giulia region). The SWOT methodology was used as a heuristic tool for organizing the available insights and the participants' discussion.
Natural sciences, historical perspectives as well as legal analysis have contributed to broadening and detailing the social capacity concept and more precisely to characterising and further specifying each particular capacity. Practitioners in the field of alpine hazards in different countries and residents of the two case study area also contributed by presenting and discussing their views and perspectives about prevention, mitigation, emergency management and recovery from natural disasters
Discovery of 59ms Pulsations from 1RXS J141256.0+792204 (Calvera)
We report on a multi-wavelength study of the compact object candidate 1RXS
J141256.0+792204 (Calvera). Calvera was observed in the X-rays with XMM/EPIC
twice for a total exposure time of ~50 ks. The source spectrum is thermal and
well reproduced by a two component model composed of either two hydrogen
atmosphere models, or two blackbodies (kT_1~ 55/150 eV, kT_2~ 80/250 eV,
respectively, as measured at infinity). Evidence was found for an absorption
feature at ~0.65 keV; no power-law high-energy tail is statistically required.
Using pn and MOS data we discovered pulsations in the X-ray emission at a
period P=59.2 ms. The detection is highly significant (> 11 sigma), and
unambiguously confirms the neutron star nature of Calvera. The pulse profile is
nearly sinusoidal, with a pulsed fraction of ~18%. We looked for the timing
signature of Calvera in the Fermi Large Area Telescope (LAT) database and found
a significant (~5 sigma) pulsed signal at a period coincident with the X-ray
value. The gamma-ray timing analysis yielded a tight upper limit on the period
derivative, dP/dt < 5E-18 s/s (dE_rot/dt <1E33 erg/s, B<5E10 G for magneto-
dipolar spin-down). Radio searches at 1.36 GHz with the 100-m Effelsberg radio
telescope yielded negative results, with a deep upper limit on the pulsed flux
of 0.05 mJy. Diffuse, soft (< 1 keV) X-ray emission about 13' west of the
Calvera position is present both in our pointed observations and in archive
ROSAT all-sky survey images, but is unlikely associated with the X-ray pulsar.
Its spectrum is compatible with an old supernova remnant (SNR); no evidence for
diffuse emission in the radio and optical bands was found. The most likely
interpretations are that Calvera is either a central compact object escaped
from a SNR or a mildly recycled pulsar; in both cases the source would be the
first ever member of the class detected at gamma-ray energies.Comment: 20 pages, 15 figures and 4 tables. Accepted for publication in MNRA
SGR 0418+5729: a low-magnetic-field magnetar
Soft gamma-ray repeaters and anomalous X-ray pulsars are a small (but
growing) group of X-ray sources characterized by the emission of short bursts
and by a large variability in their persistent flux. They are believed to be
magnetars, i.e. neutron stars powered by extreme magnetic fields 1E14-1E15 G).
We found evidence for a magnetar with a low magnetic field, SGR 0418+5729,
recently detected after it emitted bursts similar to those of soft gamma-ray
repeaters. New X-ray observations show that its dipolar magnetic field cannot
be greater than 8E12 G, well in the range of ordinary radio pulsars, implying
that a high surface dipolar magnetic field is not necessarily required for
magnetar-like activity. The magnetar population may thus include objects with a
wider range of magnetic-field strengths, ages and evolutionary stages than
observed so far.Comment: 4 pages, 2 figures; to appear in the Proceedings of the Pulsar
Conference 2010, Chia, Sardinia (Italy), 10-15 October 201
CleanET: enabling timing validation for complex automotive systems
Timing validation for automotive systems occurs in late integration stages when it is hard to control how the instances of software tasks overlap in time. To make things worse, in complex software systems, like those for autonomous driving, tasks schedule has a strong event-driven nature, which further complicates relating those task-overlapping scenarios (TOS) captured during the software timing budgeting and those observed during validation phases. This paper proposes CleanET, an approach to derive the dilation factor r caused due to the simultaneous execution of multiple tasks. To that end, CleanET builds on the captured TOS during testing and predicts how tasks execution time react under untested TOS (e.g. full overlap), hence acting as a mean of robust testing. CleanET also provides additional evidence for certification about the derived timing budgets for every task. We apply CleanET to a commercial autonomous driving framework, Apollo, where task measurements can only be reasonably collected under 'arbitrary' TOS. Our results show that CleanET successfully derives the dilation factor and allows assessing whether execution times for the different tasks adhere to their respective deadlines for unobserved scenarios.This work has been partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under grant TIN2015- 65316-P, the SuPerCom European Research Council (ERC) project under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 772773), and the HiPEAC Network of Excellence. MINECO partially supported Jaume Abella under Ramon y Cajal postdoctoral fellowship (RYC-2013-14717).Peer ReviewedPostprint (author's final draft
INTEGRAL observations of the Large Magellanic Cloud region
We present the preliminary results of the INTEGRAL survey of the Large
Magellanic Cloud. The observations have been carried out in January 2003 (about
10^6 s) and January 2004 (about 4x10^5 s). Here we concentrate on the bright
sources LMC X-1, LMC X-2, LMC X-3 located in our satellite galaxy, and on the
serendipitous detections of the Galactic Low Mass X-ray Binary EXO 0748-676 and
of the Seyfert 2 galaxy IRAS 04575-7537.Comment: 4 pages, 7 figures. To be published in the Proceedings of the 5th
INTEGRAL Workshop: "The INTEGRAL Universe", February 16-20, 2004, Munic
A Revisit of the Two-Pole Caustic Model for GeV Light Curves of Gamma-Ray Pulsars
The GeV light curve of a pulsar is an important probe to detect acceleration
regions in its magnetosphere. Motivated by the recent reports on the
observations of pulsars by {\it Fermi} Large Area Telescope (LAT), we restudy
the two-pole caustic model and revise it to investigate the properties of the
light curves in the GeV band. In the revised model, although acceleration gaps
can extend from the star surface to the light cylinder along near the last open
field lines, the extension of the gaps along the azimuthal direction is limited
because of photon-photon pair production process. In such gaps, high-energy
photons are emitted uniformly and tangentially to the field lines but cannot be
efficiently produced along these field lines where the distances to the null
charge surface are larger than times of the distance of the light
cylinder, and the effective azimuth extension of the gaps is about .
The model is applied to the four pulsars Vela, PSR J1028-5819, PSR J0205+6449,
and PSR J2021+3651 whose light curves obtained with {\it Fermi} have been
recently released. The model is successful in reproducing the general feature
of the light curves for the four pulsars, and the radial distances of the radio
pulse for the four pulsars are estimated.Comment: A reference is correcte
The study of neutron star magnetospheres with LOFT
This is a White Paper in support of the mission concept of the Large
Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We
discuss the potential of LOFT for the study of magnetospheres of isolated
neutron stars. For a summary, we refer to the paper.Comment: White Paper in Support of the Mission Concept of the Large
Observatory for X-ray Timin
Distribution in the brain and possible neuroprotective effects of intranasally delivered multi-walled carbon nanotubes
Carbon nanotubes (CNTs) are currently under active investigation for their use in several biomedical applications, especially in neurological diseases and nervous system injury due to their electrochemical properties. Nowadays, no CNT-based therapeutic products for internal use appear to be close to the market, due to the still limited knowledge on their fate after delivery to living organisms and, in particular, on their toxicological profile. The purpose of the present work was to address the distribution in the brain parenchyma of two intranasally delivered MWCNTs (MWCNTs 1 and a-MWCNTs 2), different from each other, the first being non electroconductive while the second results in being electroconductive. After intranasal delivery, the presence of CNTs was investigated in several brain areas, discriminating the specific cell types involved in the CNT uptake. We also aimed to verify the neuroprotective potential of the two types of CNTs, delivering them in rats affected by early diabetic encephalopathy and analysing the modulation of nerve growth factor metabolism and the effects of CNTs on the neuronal and glial phenotypes. Our findings showed that both CNT types, when intranasally delivered, reached numerous brain areas and, in particular, the limbic area that plays a crucial role in the development and progression of major neurodegenerative diseases. Furthermore, we demonstrated that electroconductive MWCNTs were able to exert neuroprotective effects through the modulation of a key neurotrophic factor and probably the improvement of neurodegeneration-related gliosis
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