Quality management and contractual incompleteness: grape procurement for high-end wines in Argentina

International audienceSourcing grapes from independent growers for use in top quality wines sold on the international market is a major organisational challenge for corporate wineries. Our paper adds to the small existing literature addressing these coordination issues in the New World wine sector, by going deeper into the specifics of the contracts, as well as the "transaction cost economising" argument. Based on a case-study carried out in the Argentine province of Mendoza, this article presents an in-depth analysis of the technical process, in order to identify the contractual hazards posed by asset specificity, measurement costs, and non-contractible actions. Drawing on contract completion and dual sourcing literature, it analyses the contractual and non contractual mechanisms (price incentives, grower monitoring, allocation of decision rights to the winery, role of backward integration into production) used to govern such grape transactions. Through our analysis, we were able to arrive at four main conclusions. Firstly, most agreements are still verbal, with the exception of occasional written contracts, limited to a few legal provisions. It became clear to us that this approach to forging agreements is not always adequate in managing the inherently complex interactions between grape varieties, soil, farming practices and wine-making processes in high-end wine production. Secondly, extensive decision rights are allocated to wineries, to deal with incompleteness. These are key decisions to be taken during the cropping and harvesting process. Thirdly, pricing is generally kept flexible, with grape prices negotiated ex-post. This means that trade imbalances tend to be resolved in the long term. Winegrowers also benefit from financial rewards to compensate for allocations. Finally, any potential opportunistic behaviour by wineries with regards to asset specificity (in particular yield limitation) and allocation of rights is kept at bay by mechanisms such as winery reputations and credit third-party guaranty. This type of behaviour by growers is similarly deterred through monitoring and vineyard ownership on the part of the wineries

Non-universality of artificial frustrated spin systems

Magnetic frustration effects in artificial kagome arrays of nanomagnets with out-of-plane magnetization are investigated using Magnetic Force Microscopy and Monte Carlo simulations. Experimental and theoretical results are compared to those found for the artificial kagome spin ice, in which the nanomagnets have in-plane magnetization. In contrast with what has been recently reported, we demonstrate that long range (i.e. beyond nearest-neighbors) dipolar interactions between the nanomagnets cannot be neglected when describing the magnetic configurations observed after demagnetizing the arrays using a field protocol. As a consequence, there are clear limits to any universality in the behavior of these two artificial frustrated spin systems. We provide arguments to explain why these two systems show striking similarities at first sight in the development of pairwise spin correlations.Comment: 7 pages, 6 figure

Torque magnetometry of perpendicular anisotropy exchange-spring heterostructures

International audienceThe field-induced magnetic configurations in a [Co/Pd]15 /TbFeCo exchange-spring system with perpendicular magnetic anisotropy are studied using torque magnetometry. The experimental results are compared to a 1D micromagnetic simulation. The good agreement between experiments and simulations allows us to deduce the evolution of the in-depth magnetic configuration as a function of the applied field orientation and amplitude. The chirality transition of the interfacial domain wall developing in the structure can also be determined with this technique

Spectroscopic studies of GTA welding plasmas. Temperature calculation and dilution measurement

International audienc

Indigenous Australians and the National Disability Insurance Scheme

The National Disability Insurance Scheme (NDIS) is one of the major policy innovations of the early 21st century in Australia, representing a new way of delivering services to people with a disability and those who care for them

Extensive degeneracy, Coulomb phase and magnetic monopoles in an artificial realization of the square ice model

Artificial spin ice systems have been introduced as a possible mean to investigate frustration effects in a well-controlled manner by fabricating lithographically-patterned two-dimensional arrangements of interacting magnetic nanostructures. This approach offers the opportunity to visualize unconventional states of matter, directly in real space, and triggered a wealth of studies at the frontier between nanomagnetism, statistical thermodynamics and condensed matter physics. Despite the strong efforts made these last ten years to provide an artificial realization of the celebrated square ice model, no simple geometry based on arrays of nanomagnets succeeded to capture the macroscopically degenerate ground state manifold of the corresponding model. Instead, in all works reported so far, square lattices of nanomagnets are characterized by a magnetically ordered ground state consisting of local flux-closure configurations with alternating chirality. Here, we show experimentally and theoretically, that all the characteristics of the square ice model can be observed if the artificial square lattice is properly designed. The spin configurations we image after demagnetizing our arrays reveal unambiguous signatures of an algebraic spin liquid state characterized by the presence of pinch points in the associated magnetic structure factor. Local excitations, i.e. classical analogues of magnetic monopoles, are found to be free to evolve in a massively degenerated, divergence-free vacuum. We thus provide the first lab-on-chip platform allowing the investigation of collective phenomena, including Coulomb phases and ice-like physics.Comment: 26 pages, 10 figure

Expanding Transformative Experience

We develop a broader, more fine-grained taxonomy of forms of transformative experience, inspired by the work of L. A. Paul. Our vulnerability to such experiences arises, we argue, due to the vulnerability, dependence, and affliction intrinsic to the human condition. We use this trio to distinguish a variety of positively, negatively, and ambivalently valenced forms of epistemically and/or personally transformative experiences. Moreover, we argue that many transformative experiences can arise gradually and cumulatively, unfolding over the course of longer periods of time