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Integrating Agriculture in Greenways: a Methodology for Planning Connected Urban and Peri-Urban Farmlands in a Mediterranean City
Cities are often threatened by a loss of environmental quality due the rapid increase of urbanized areas that fragment natural landscapes. This is particularly true at the cities’ fringe where uncontrolled urbanization is often characterized by discontinuous patterns and consequent fragmentation of farmlands. These phenomena are particularly relevant in Mediterranean cities, where the high degree of land-use transitions, a consequence of urban growth with poor environmental regulations produce urban landscapes characterized by a lack of green areas and high levels of ecological fragmentation (EEA, 2006).
Greenways are one of the most powerful and widespread tools used at urban, metropolitan and regional scales. Their aim is to counteract ecological fragmentation and to integrate urban development, nature conservation and public health promotion (Ahern, 1995; Fabos & Ryan, 2006). They facilitate linkages between rural and urban spaces along the rural-urban interface through linear systems (Walmsley, 2006). As networks of linear elements they are planned, designed and managed for multiple purposes, including the provision of ecosystem services such as purification of air and water, mitigation of floods, climate regulation, generation and renewal of soil fertility, accessibility to open spaces and intellectual stimulation. Urban contexts present particular challenges for greenways development due to the complex arrangement of urban landscape features. The large number and diversity of land-cover types often produce high degrees of fragmentation of open spaces and heterogeneity of their roles and functions. For this reason a number of different types of patches of Non Urbanized Areas (NUAs) are present in urban contexts: this calls for a characterization of these spaces in order to highlight their physical features and their ecological and social functions. Particularly, they could represent a big opportunity for planning policies oriented to support new forms of urban agriculture (La Greca et al., 2011a).
When formulating planning approaches to greenways in urban contexts, new forms of agriculture have been the focus of very few studies and applications but they can significantly contribute to cities’ sustainability (Zasada, 2011). Proposing an agricultural greenway that integrates different NUAs into a network of farmlands and other green spaces (parks, playgrounds and so on) could significantly improve the overall accessibility of these areas, redefining the rural-urban interface and enhancing the provision of urban ecosystem services
Evaluating The Potential Energy Savings Of An Urban Green Infrastructure Through Environmental Simulation
Green infrastructure is a very important aspect to be considered in designing and preparing cities to adapt and mitigate climate change impacts on the built environment. Green based solutions have a strong impact on many aspects, such as controlling storm-water, reducing urban heat island effect, stabilizing soils, facing earthquakes, etcetera. In this paper an environmental analysis is performed by simulation with TRNSYS Studio tool. The cooling potential that can be obtained by trees in residential compounds is assessed, considering shadowing effect, changes in air movement, sky view factor reduction and other simulation-parameter changes. Results show that a reduction of 30 to 50% in cooling demand can be obtained by using a raw of trees on South, East and especially West façades. Two types of trees are tested, showing different cooling performances depending on the height and form of the trees
Low temperature deactivation of Ge heavily n-type doped by ion implantation and laser thermal annealing
International audienceHeavy doping of Ge is crucial for several advanced micro-and optoelectronic applications, but, at the same time, it still remains extremely challenging. Ge heavily n-type doped at a concentration of 1 X 10(20) cm(-3) by As ion implantation and melting laser thermal annealing (LTA) is shown here to be highly metastable. Upon post-LTA conventional thermal annealing As electrically deactivates already at 350 degrees C reaching an active concentration of similar to 4 x 10(19) cm(-3). No significant As diffusion is detected up to 450 degrees C, where the As activation decreases further to similar to 3 x 10(19) cm(-3). The reason for the observed detrimental deactivation was investigated by Atom Probe Tomography and in situ High Resolution X-Ray Diffraction measurements. In general, the thermal stability of heavily doped Ge layers needs to be carefully evaluated because, as shown here, deactivation might occur at very low temperatures, close to those required for low resistivity Ohmic contacting of n-type Ge
Green Infrastructure to reduce cooling loads and heat stress in Mediterranean Climates
Climate change impact on cities and urban warming due to anthropogenic effects are urgent problems to be solved. Among the most beneficious strategies to reduce those impacts we can account the development of green infrastructures in cities, a kind of intervention that assure both mitigation of global warming by reducing greenhouse gases emissions, and adaptation to warmer urban environments. This work presents a building simulation and machine learning methodology to estimate the energy and comfort-related benefits that can be obtained by using a green infrastructure to shadow buildings' façades and roofs. We used previously developed simulation models to test the energy savings provided by different types of trees planted to produce shadows on buildings. Then, we tested different algorithms to predict using a machine learning approach the saving that can be obtained in different buildings-trees contexts for the cities of Catania, Rome, Santiago de Chile and Viña del
Mar. Results show that the saving obtained is in the range 5-60%, mainly depending on the number of façade shadowed and on the specie of trees; and the prediction accuracy of machine learning process is over 90% for a binary classification (energy saving > 15% or <15%
Vacancy generation in liquid phase epitaxy of Si
Concerted experiments and theoretical analysis are applied to conclusively demonstrate the vacancy generation during fast melting and regrowth of Si by laser irradiation. Experiments, based on the positron annihilation spectroscopy and designed to test the theoretical predictions, evidence a vacancy supersaturation after the laser process depending on the irradiation conditions. Stochastic atomistic simulations of the molten Si recrystallization show trapping of vacancies in the recrystallized region. Finally, continuum phase-field simulations of the full process, calibrated using the Monte Carlo results, show a defect evolution in close agreement with the experiments.Peer reviewe
Perspectives and advantages of the use of excimer laser annealing for MOS technology
The integration of excimer laser annealing (ELA) into the MOS device technology has been studied and evaluated within the frame of the IST project FLASH (Fundamentals and applications of laser processing for highly innovative MOS technology), funded by the European Commission. The final aim of the project was to demonstrate that ELA can be applied as a reliable, effective and advantageous process in the context of semiconductor device fabrication. Some of the results of this activity are summarised, relative to the experimental characterization and theoretical modelling. The electrical characterization of the transistor fabricated by ELA is also presented, showing a device yield of 90% on wafer
Use of hormones in doping and cancer risk
Hormones with anabolic properties such as growth hormone (GH) and insulin-like growth factor-1 (IGF-1) are commonly abused among professional and recreational athletes to enhance physical ability. Despite their adverse effects are well-documented, the use of GH and IGF-1 has recently grown. This article highlights the anabolic activity related to mechanisms of cancer development and progression. GH/IGF-1 axis is able to activate cellular mechanisms that modulate every key stage of cancer formation and progression, such as inhibition of apoptosis, resistance to treatments, and induction of angiogenesis, metastatic process and cell proliferation. Results from pre-clinical studies and epidemiological observations in patients with an excess of GH and IGF-1 production or treated with these hormones showed a positive association with the risk to develop several types of cancer. In conclusion, athletes should be made aware that long-term treatment with doping agents might increase the risk of developing cancer, especially if associated with other licit or illicit drugs and/or high-protein diet
CATANA protontherapy facility: The state of art of clinical and dosimetric experience
After nine years of activity, about 220 patients have been treated at the CATANA Eye Protontherapy facility. A 62MeV proton beam produced by a Superconducting Cyclotron is dedicated to radiotherapy of eye lesions, as uveal melanomas. Research and development work has been done to test different dosimetry devices to be used for reference and relative dosimetry, in order to achieve dose delivering accuracy. The follow-up results demonstrated the efficacy of proton beams and encouraged us in our activity in the fight against cancer
Insulator-metal transition in biased finite polyyne systems
A method for the study of the electronic transport in strongly coupled
electron-phonon systems is formalized and applied to a model of polyyne chains
biased through metallic Au leads. We derive a stationary non equilibrium
polaronic theory in the general framework of a variational formulation. The
numerical procedure we propose can be readily applied if the electron-phonon
interaction in the device hamiltonian can be approximated as an effective
single particle electron hamiltonian. Using this approach, we predict that
finite polyyne chains should manifest an insulator-metal transition driven by
the non-equilibrium charging which inhibits the Peierls instability
characterizing the equilibrium state.Comment: to appear at EPJ
A double Seismic Array Experiment on Mt. Etna
On September 1999 two seismic antennas (array) and a profile of 3-D stations
equipped with short period seismometers were installed on Mt. Etna; Aims of the experiment
were to investigate the structure and the polarisation parameters of the volcanic tremor
wavefield radiated in eruptive conditions, and to measure the seismic velocities and
attenuation in the shallow structure beneath the arrays. The first array was installed close to
Pizzi Deneri Volcanological Observatory, East of the crater area; the second array was located
close to Torre del Filosofo site, south of the crater area. The profile was set up close to the
Pizzi Deneri array. It had a length of 600 meters and consisted of 16 short period 3-
component stations. In addition, a circular array of 8 short period seismometers was set up
around the main crater area (Fig. 1). Several tremor samples and explosions quakes were
recorded in 10 days of operation .
Spectrograms show predominant energy into 1-4 Hz frequency band. Slowness spectra
indicate a predominant source of the tremor located at surface and coincident with the crater
area. Polarisation analysis show that the direction of predominant motion is transverse with
respect to the direction pointing to the active craters.INGV - Osservatorio VesuvianoUnpublishedope
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