94 research outputs found
Corporate Security Responsibility: Towards a Conceptual Framework for a Comparative Research Agenda
The political debate about the role of business in armed conflicts has increasingly raised expectations as to governance contributions by private corporations in the fields of conflict prevention, peace-keeping and postconflict peace-building. This political agenda seems far ahead of the research agenda, in which the negative image of business in conflicts, seen as fuelling, prolonging and taking commercial advantage of violent conflicts,still prevails. So far the scientific community has been reluctant to extend the scope of research on âcorporate social responsibilityâ to the area of security in general and to intra-state armed conflicts in particular. As a consequence, there is no basis from which systematic knowledge can be generated about the conditions and the extent to which private corporations can fulfil the role expected of them in the political discourse. The research on positive contributions of private corporations to security amounts to unconnected in-depth case studies of specific corporations in specific conflict settings. Given this state of research, we develop a framework for a comparative research agenda to address the question: Under which circumstances and to what extent can private corporations be expected to contribute to public security
Time-resolved single-crystal X-ray crystallography
In this chapter the development of time-resolved crystallography is traced from its beginnings more than 30Â years ago. The importance of being able to âwatchâ chemical processes as they occur rather than just being limited to three-dimensional pictures of the reactant and final product is emphasised, and time-resolved crystallography provides the opportunity to bring the dimension of time into the crystallographic experiment. The technique has evolved in time with developments in technology: synchrotron radiation, cryoscopic techniques, tuneable lasers, increased computing power and vastly improved X-ray detectors. The shorter the lifetime of the species being studied, the more complex is the experiment. The chapter focusses on the results of solid-state reactions that are activated by light, since this process does not require the addition of a reagent to the crystalline material and the single-crystalline nature of the solid may be preserved. Because of this photoactivation, time-resolved crystallography is often described as âphotocrystallographyâ. The initial photocrystallographic studies were carried out on molecular complexes that either underwent irreversible photoactivated processes where the conversion took hours or days. Structural snapshots were taken during the process. Materials that achieved a metastable state under photoactivation and the excited (metastable) state had a long enough lifetime for the data from the crystal to be collected and the structure solved. For systems with shorter lifetimes, the first time-resolved results were obtained for macromolecular structures, where pulsed lasers were used to pump up the short lifetime excited state species and their structures were probed by using synchronised X-ray pulses from a high-intensity source. Developments in molecular crystallography soon followed, initially with monochromatic X-ray radiation, and pump-probe techniques were used to establish the structures of photoactivated molecules with lifetimes in the micro- to millisecond range. For molecules with even shorter lifetimes in the sub-microsecond range, Laue diffraction methods (rather than using monochromatic radiation) were employed to speed up the data collections and reduce crystal damage. Future developments in time-resolved crystallography are likely to involve the use of XFELs to complete âsingle-shotâ time-resolved diffraction studies that are already proving successful in the macromolecular crystallographic field.</p
Sound Symbolism Facilitates Word Learning in 14-Month-Olds
Sound symbolism, or the nonarbitrary link between linguistic sound and meaning, has often been discussed in connection with language evolution, where the oral imitation of external events links phonetic forms with their referents (e.g., Ramachandran & Hubbard, 2001). In this research, we explore whether sound symbolism may also facilitate synchronic language learning in human infants. Sound symbolism may be a useful cue particularly at the earliest developmental stages of word learning, because it potentially provides a way of bootstrapping word meaning from perceptual information. Using an associative word learning paradigm, we demonstrated that 14-month-old infants could detect Köhler-type (1947) shape-sound symbolism, and could use this sensitivity in their effort to establish a wordreferent association
Recommended from our members
A review of operational methods of variational and ensemble-variational data assimilation
Variational and ensemble methods have been developed separately by various research and development groups and each brings its own benefits to data assimilation. In the last decade or so various ways have been developed to combine these methods, especially with the aims of improving the background error covariance matrices and of improving efficiency. The field has become confusing, even to many specialists, and so there is now a need to summarise the methods in order to show how they work, how they are related, what benefits they bring, why they have been developed, how they perform, and what improvements are pending. This paper starts with a reminder of basic variational and ensemble techniques and shows how they can be combined to give the emerging ensemble-variational (EnVar) and hybrid methods. A key part of the paper includes details of how localisation is commonly represented.
There has been a particular push to develop four-dimensional methods that are free of linearised forecast models. This paper attempts to provide derivations of the formulations of most popular schemes. These are otherwise scattered throughout the literature or absent. It builds on the nomenclature used to distinguish between methods, and discusses further possible developments to the methods, including the representation of model error
- âŠ