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Chengdu, China

Cocciufa C.,CFS | Cerretti P.,Centro Nazionale per lo Studio e la Conservazione della Biodiversita Forestale Bosco della Fontana | Matteucci G.,CNR Institute for Agricultural and Forest Systems In the Mediterranean | Matteucci G.,CNR Institute of Agro-environmental and Forest Biology | Carpaneto G.M.,Third University of Rome
IForest | Year: 2011

Italy entered the International Long Term Ecological Research Network (ILTER) in 2006, contributing a group of research sites in marine, freshwater and terrestrial ecosystems to the global network. Five forest sites are included in the Italian Network. They are representative of the main forest ecosystems in Italy and integrate 15 research stations managed by different institutes. Starting from LTER rationale and basic concepts, the first part of the paper reviews the status of LTER Italy forest sites, the strengths resulting from multidisciplinary expertise and site management, current activities and available datasets. Long term data series on key environmental parameters show the high scientific value of these sites, where monitoring and/or research is still ongoing. But two main LTER issues are currently arising in the international context: (1) overall consistency of datasets; (2) harmonization of sampling methods. For this reason, the second part of the paper investigates the suitability of Italian forest sites to address recommended long term research topics and ecological issues of global concern and to investigate the shift from in-site monitoring to crosssite cooperation and inter-site research. © iForest - Biogeosciences and Forestry.

Alam M.M.,Kyushu University | Nakamura K.,Kyushu University | Hasegawa M.,Kyushu University | Tokunaga K.,Kyushu University | And 11 more authors.
Proceedings - Symposium on Fusion Engineering | Year: 2016

We investigate and calculate particle orbits and the effect of particle orbits on plasma current density for nonrelativistic resonance condition in the present RF-driven divertor plasma on QUEST. We surveyed particle orbits for different values of parallel refractive index, particle initial positions and pitch angles on fundamental and second harmonic resonance conditions. We observed that for fundamental harmonic resonance condition when particle orbits are plotted on the poloidal cross-section for positive values of parallel refractive index, these orbits are started from the resonance surface and produced their orbits around the LCFS (Large Closed Flux Surface). These orbits carry positive current. When particle orbits are plotted for negative values of parallel refractive index, these orbits are started from resonance surface, but remained at the inside of the LCFS. These orbits carry negative current that reduced the overall plasma current. For second harmonic resonance condition when particle orbits are plotted on the poloidal cross-section most of the orbits remained in inside the LCFS and carry positive current. When we consider the value of parallel refractive index-0.4 and +0.4 some particle orbits arrived at the limiter and become lost particles. On the other hand, when we consider particle initial positions 0.16 m or more vertically far from the mid plane some banana orbits are produced. These banana orbits make the current density profile maximum at low field side region. From this calculation we got a hollow current density profile with current density peak at the low field side region outside of the LCFS. From this calculation we can infer that parabolic current density profile is possible, if we set the resonance surface outside of the magnetic axis by increasing the toroidal magnetic field coil current and make the plasma position inward by increasing vertical field coil current. © 2015 IEEE.

Berdajs D.,University of Lausanne | Mosbahi S.,University of Lausanne | Forro Z.,ETH Zurich | Gerber C.,University of Zurich | And 3 more authors.
European Journal of Cardio-thoracic Surgery | Year: 2016

OBJECTIVES: The aim was to define the 3-dimensional (3D) geometrical changes of the aortic root and to determine the local shear stress profile of aortic root elements during the cardiac cycle. METHODS: Six sonomicrometric crystals (200 Hz) were implanted into the aortic root of five pigs at the commissures and at the aortic root base (AoB). 3D aortic root deformation including volume, torsion and tilt angle were determined. Geometrical data with measured local flow and pressure conditions was used for computed fluid dynamics modelling of the aortic root. RESULTS: Compared with end-diastole, the sinotubular junction and AoB have maximal expansion at peak ejection: 16.42 ± 6.36 and 7.60 ± 2.52%, and minimal at isovolaemic relaxation: 2.87 ± 1.62 and 1.85 ± 1.79%. Aortic root tilt and rotation angle were maximal at the end of diastole: 17.7 ± 8.8 and 21.2 ± 2.09°, and decreased to 15.24 ± 8.14 and 18.3 ± 0.1.94° at peak ejection. High shear stress >20 Pa was registered at peak ejection at coaptations, and during diastole at the superior two-thirds of the leaflets and intervalvular triangles (IVTs). The leaflet body, inferior one-third of the IVTs and valve nadir were exposed to moderate shear stress (8-16 Pa) during the cardiac cycle. CONCLUSIONS: Aortic root geometry demonstrates precise 3D changes of tilt and rotation angle. Reduction of angles during ejection results in a straight cylinder with low shear stress that facilitates the ejection; the increase during diastole results in a tilted frustum with elevated shear stress. Findings can be used for comparative analysis of native and synthetic structures with individual compliance. © The Author 2015.

Alam M.M.,Kyushu University | Nakamura K.,Kyushu University | Xia F.,CFS | Mitarai O.,Tokai University | And 12 more authors.
Fusion Engineering and Design | Year: 2015

In the present RF-driven divertor plasma of QUEST, it has been observed that orbit-driven current flows in the open magnetic surfaces outside of the closed magnetic surfaces. To observe this phenomenon and the characteristics of the orbit-driven current, current density profiles have been calculated on two different equilibrium conditions. We calculated current density profiles from particle guiding center orbits both for the fundamental and the second harmonic resonances for the 8.2. GHz electron cyclotron current drive. From this calculation, hollow current density profiles have been obtained with significant characteristics on both conditions. Only positive current distribution has been observed in the open magnetic surfaces outside of the closed magnetic surfaces. © 2015 Elsevier B.V.

Nakamura K.,Kyushu University | Fujita H.,Kyushu University | Liu X.L.,CFS | Xue E.B.,ECUST | And 18 more authors.
2013 IEEE 25th Symposium on Fusion Engineering, SOFE 2013 | Year: 2013

In the present RF-driven plasma with a lot of high-energy electrons, there may be anisotropic plasma pressure, which makes difficult a usual equilibrium analysis, but the CCS method can reconstruct the plasma shape precisely regardless of the anisotropy. And the plasma current effect in the open magnetic surfaces outside of the closed magnetic surfaces is considered in the RF-driven plasma. Further high-energy particle guiding center orbits are calculated aiming at estimation of the open-magnetic-surface current distribution. © 2013 IEEE.

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