321 research outputs found
Multi-Criteria Analysis and Decision-Making Approach for the Urban Regeneration: The Application to the Rimini Canal Port (Italy)
In recent decades, urban settlements have been greatly affected by globalisation, climate change, and economic uncertainty. When designing cities, these factors should be taken into account and adapted to the different contexts involved. The redevelopment of degraded urban areas is the first step toward achieving the sustainability aims set out in the Sustainable Development Goals. In this context, evaluation methods are required in the decision-making process, considering different social, economic, and environmental aspects to define the correct policies and actions for city redevelopment. In this paper, an evaluation methodology is proposed in order to obtain a priority scale of interventions for urban regeneration. Starting from on-site inspections to better know the current scenario, a set of indicators is established to evaluate the urban quality. Criticalities and potentials emerge through SWOT analysis and, with the ANP-BOCR method, the priority scale of the identified scenarios is defined. This decision-making approach was applied to the case study of the Rimini Canal Port, in the northeast of Italy, which is a degraded area of the city. This methodology is a tool that can be used in the future by decision makers (DMs) for the redevelopment of small port areas within similar urban contexts
When and how? Freshwater mussel recolonization in Lake Orta
Thanks to a video posted on a social network, live mussels of Unio elongatulus, have been recorded from Lake Orta (Italy) over one century after the last (and only) report. With its long and well documented history of pollution, Lake Orta offers the opportunity to document the post-extirpation recovery of freshwater unionid mussels. This case evidences that recovery/recolonization is possible despite a high devastation in the past, and permits to evaluate how fast recolonization may occur, in which way, and in what conditions. The answer to the \u27how fast\u27 was sought by estimating the age of the larger and seemingly older individuals of the population. To address the \u27in which way\u27 we compared the haplotypes of Lake Orta specimens of Unio elongatulus (the only species present) with those of surrounding populations. We concluded that, since Lake Orta lacks a direct connection with the putative source populations, colonizing mussels were almost certainly transported by fish carrying glochidia that were used for lake restocking after liming. Data from the long-term monitoring of water chemistry and sediments have allowed defining what conditions proved to be suitable for survival making possible the start of mussels recovery. But not only water and sediment quality matters for mussels recovery, which was delayed by nearly ten years after the reappearance of fish. This delay reflects the need of the whole trophic chain to be reestablished to allow the survival of the suitable and healthy host-fish populations necessary for mussels reproduction
Magnetic frustration, phase competition, and the magnetoelectric effect in NdFe3(BO3)4
PACS numbers: 75.85.+t, 75.25. j, 75.30.Et, 78.70.Ck.-- et al.We present an element selective resonant magnetic x-ray scattering study of NdFe3(BO3)4 as a function of temperature and applied magnetic field. Our measurements show that the magnetic order of the Nd sublattice is induced by the Fe spin order. When a magnetic field is applied parallel to the hexagonal basal plane, the helicoidal spin order is suppressed and a collinear ordering, where the moments are forced to align in a direction perpendicular to the applied magnetic field, is stabilized. This result excludes a noncollinear spin order as the origin of the magnetically induced electric polarization in this compound. Instead our data imply that magnetic frustration results in a phase competition, which is the origin of the magnetoelectric response.This work was supported by the DFG through the Emmy Noether Programme (Grant No. GE1647/2-1) and the European Community’s Seventh Framework Program (FP7/2007-2013) under Grant No. 226716.Peer reviewe
The role of social networks and citizen science in environmental research: the unexpected revival of freshwater mussels in Lake Orta
Social networks are increasingly used for many conservation and environmental educational purposes. The usefulness for ecological studies is exemplified by the casual discovery of the recovery of freshwater mussels in Lake Orta. Mussels were extirpated by severe industrial pollution soon after 1926 and over the following decades their recovery was prevented by acidification and increase of metal concentrations. Even after the improvement of water conditions obtained by limning, the lack of mussels was taken for granted based on the legacy effects of accumulated toxins in the sediments, and on the limited potential for most extirpated species of mussels to naturally recolonize. The probability of mussel\u27s recovery in Lake Orta was considered poor also for the apparent lack of access to restocking populations, which is essential to start the natural recolonization of an area. Because of the assumption that mussels were absent and of the difficulties of locating mussels their recolonization went unnoticed for about 15 years. Only in 2014 the casual discovery of mussels in Lake Orta was made possible thanks to an amateur video posted on YouTube and delivered to one of us through Facebook: this highlights once more the potential role of social networks for conservation and environmental issues. Freshwater mussels are challenging to locate because they are often rare, spatially clustered, and difficult to detect. The recolonization of Lake Orta went unnoticed probably due to the limited extent of the colonized area, low density and, at least initially, the small size of individuals. In such cases the contribution of citizen science can be crucial to provide the reporting even of small populations present in restricted areas and/or not easily accessible. An extensive search along the lake perimeter is being performed through the volunteer collaboration of local SCUBA divers and an online survey through social networks
Pesi da telaio romani dalla Venetia fra archeologia, epigrafia e archeometria
As a part of a project conducted by the University of Padua on the wool production in the Roman Venetia, the paper focuses on a group of loom weights found in the late nineteenth century near Castagnaro (Verona). The integrated analysis (archeology, epigraphy and archaeometry) conducted on the loom weights allow to reflect on the marking of the loom weights and on the organization of the production in a Roman figlina.Nel quadro di un Progetto sulla lavorazione della lana nella Venetia romanacondotto dall’Università di Padova, il contributo presenta i risultati di un’analisi integrata fra archeologia, epigrafia e archeometria relativamente a una serie di pesi da telaio rinvenuti a fine Ottocento presso Castagnaro (Verona). I manufatti, con buona probabilità prodotti in una stessa fornace, offrono l’occasione per una riflessione sulla bollatura di tale categoria di oggetti e sull’organizzazione del lavoro nelle figlinae romane
Urban Regeneration and Soft Mobility: The Case Study of the Rimini Canal Port in Italy
The increasing need to reduce emissions and the environmental impact of urban areas to meet European decarbonisation goals motivates the selection of the Rimini Canal Port as a case study within the FRAMESPORT project, part of the European Interreg Italy–Croatia programme. A preliminary historical–documental and urban regulations analysis of the context allowed the
identification of the main criticalities and potentials through a SWOT analysis. The central role
of the stakeholders enabled the creation of a successful participatory co-design process developed
through online surveys. Critical issues that emerged during the data collection phase were prioritised through a BOCR model, a powerful multi-criteria analysis tool. The project phase then focused on the resolution of the two main critical issues that emerged: the improvement of cycle/pedestrian paths, and the raising of the flooding docks in the Canal Port area. This article intends to demonstrate the strong influence of soft mobility in urban regeneration projects, and how an improvement of the quality of cycle/pedestrian paths can increase the quality of urban spaces. The new paths create a green infrastructure that contributes to a reduction in pollutant emissions through the promotion of sustainable mobility systems and an increase in green urban spaces
On the role of intrinsic disorder in the structural phase transition of magnetoelectric EuTiO3
Up to now the crystallographic structure of the magnetoelectric perovskite
EuTiO3 was considered to remain cubic down to low temperature. Here we present
high resolution synchrotron X-ray powder diffraction data showing the existence
of a structural phase transition, from cubic Pm-3m to tetragonal I4/mcm,
involving TiO6 octahedra tilting, in analogy to the case of SrTiO3. The
temperature evolution of the tilting angle indicates a second-order phase
transition with an estimated Tc=235K. This critical temperature is well below
the recent anomaly reported by specific heat measurement at TA\sim282K. By
performing atomic pair distribution function analysis on diffraction data we
provide evidence of a mismatch between the local (short-range) and the average
crystallographic structures in this material. Below the estimated Tc, the
average model symmetry is fully compatible with the local environment
distortion but the former is characterized by a reduced value of the tilting
angle compared to the latter. At T=240K data show the presence of local
octahedra tilting identical to the low temperature one, while the average
crystallographic structure remains cubic. On this basis, we propose intrinsic
lattice disorder to be of fundamental importance in the understanding of EuTiO3
properties.Comment: 13 pages, 8 figures, 2 table
Distinct fingerprints of charge density waves and electronic standing waves in ZrTe
Experimental signatures of charge density waves (CDW) in high-temperature
superconductors have evoked much recent interest, yet an alternative
interpretation has been theoretically raised based on electronic standing waves
resulting from quasiparticles scattering off impurities or defects, also known
as Friedel oscillations (FO). Indeed the two phenomena are similar and related,
posing a challenge to their experimental differentiation. Here we report a
resonant X-ray diffraction study of ZrTe, a model CDW material. Near the
CDW transition, we observe two independent diffraction signatures that arise
concomitantly, only to become clearly separated in momentum while developing
very different correlation lengths in the well-ordered state. Anomalously slow
dynamics of mesoscopic ordered nanoregions are further found near the
transition temperature, in spite of the expected strong thermal fluctuations.
These observations reveal that a spatially-modulated CDW phase emerges out of a
uniform electronic fluid via a process that is promoted by self-amplifying FO,
and identify a viable experimental route to distinguish CDW and FO.Comment: 6 pages, 4 figures; supplementary information available upon reques
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