2,452 research outputs found
Knowledge, Food and Place: a way of producing a way of knowing
The article examines the dynamics of knowledge in the valorisation of local food, drawing on the results from the CORASON project (A cognitive approach to rural sustainable development: the dynamics of expert and lay knowledge), funded by the EU under its Framework Programme 6. It is based on the analysis of several in-depth case studies on food relocalisation carried out in 10 European countries
Compressive Properties of Trabecular Bone in the Distal Femur
Early loosening and implant migration are two problems that lead to failures in cementless (press-fit) femoral knee components of total knee replacements. To begin to address these early failures, this study determined the anterior–posterior mechanical properties from four locations in the human distal femur. Thirty-three cylindrical specimens were removed perpendicular to the press-fit surface after the surgical cuts on 10 human cadaveric femurs (age 71.5 ± 14.2 years) had been made. Compression testing was performed that utilized methods to reduce the effects of end-artifacts. The bone mineral apparent density (BMAD), apparent modulus of elasticity, yield and ultimate stress, and yield and ultimate strain were measured for 28 cylindrical specimens. The apparent modulus, yield and ultimate stress, and yield and ultimate strain each significantly differed (p\u3c0.05) in the superior and inferior locations. Linear and power law relationships between superior and inferior mechanical properties and BMAD were determined. The inferior apparent modulus and stresses were higher than those in the superior locations. These results show that the press-fit fixation characteristics of the femoral knee component differ on the anterior shield and posterior condyles. This information will be useful in the assignment of mechanical properties in finite element models for further investigations of femoral knee components. The property–density relations also have applications for implant design and preoperative assessment of bone strength using clinically available tools
Measurement of the ground-state flux diagram of three coupled qubits as a first step towards the demonstration of adiabatic quantum computation
The ground state susceptibility of a system consisting of three flux-qubits
was measured in the complete three dimensional flux space around the common
degeneracy point of the qubits. The system's Hamiltonian could be completely
reconstructed from measurements made far away from the common degeneracy point.
The subsequent measurements made around this point show complete agreement with
the theoretical predictions which follow from this Hamiltonian. The ground
state anti-crossings of the system could be read-out directly from these
measurements. This allows one to determine the ground-state flux diagram, which
provides the solution for the non-polynomial optimization problem MAXCUT
encoded in the Hamiltonian of the three-flux-qubit system. Our results show
that adiabatic quantum computation can be demonstrated with this system
provided that the energy gap and/or the speed of the read-out is increased.Comment: accepted for publication by Europhysics Letter
Molecular dynamics simulations of a fully hydrated dipalmitoyl phosphatidylcholine bilayer with different macroscopic boundary conditions and parameters
We compared molecular dynamics simulations of a bilayer of 128 fully hydrated phospholipid (DPPC) molecules, using different parameters and macroscopic boundary conditions. The same system was studied under constant pressure, constant volume, and constant surface tension boundary conditions, with two different sets of charges, the single point charge (SPC) and extended single point charge (SPC/E) water model and two different sets of Lennard-Jones parameters for the interaction between water and methyl/methylene. Some selected properties of the resulting bilayer systems are compared to each other, previous simulations, and experimental data. It is concluded that in relatively high water concentration it is possible to use ab initio derived charges with constant pressure boundary conditions. The SPC water model gives a larger area per head group and a broader interface than the SPC/E model. Increasing the repulsion between water oxygens and CH2/CH3 groups has a large effect on the width of the interface and the area per head group. There is little difference between simulations with constant pressure and constant surface tension. The use of constant volume, using a reasonable estimate for the initial box dimensions, easily introduces artefacts. (C) 1996 American Institute of Physics
The relationships between internal and external threat and right-wing attitudes: A three-wave longitudinal study
The interplay between threat and right-wing attitudes has received much research attention, but its longitudinal relationship has hardly been investigated. In this study, we investigated the longitudinal relationships between internal and external threat and right-wing attitudes using a cross-lagged design at three different time points in a large nationally representative sample (N = 800). We found evidence for bidirectional relationships. Higher levels of external threat were related to higher levels of Right-Wing Authoritarianism and to both the egalitarianism and dominance dimensions of Social Dominance Orientation at a later point in time. Conversely, higher levels of RWA were also related to increased perception of external threat later in time. Internal threat did not yield significant direct or indirect longitudinal relationships with right-wing attitudes. Theoretical and practical implications of these longitudinal effects are discussed
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