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Tool fingerprinting: Characterising management tools
Academics have long been interested in understanding the nature of management tools such as roadmapping or scenario planning and to derive guidance on how they should be used. A typical approach to this challenge has been proposing rules and classifications to select and configure management tools. However, none of those proposed so far has been universally recognised. This paper argues that the characterisation of instances of tools implementation (tools-in-action) according to five key dimensions allows an easier and more robust approach to theoretically understand tools and to help practitioners with the configuration of toolkits. In order to highlight the advantages and the potential limitations of this characterization approach, a toolkit is examined.This is the author's accepted manuscript. The final version has been published by IEEE in Proceedings of PICMET '14: Infrastructure and Service Integration at http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=692132
Atomistic Molecular Dynamics Simulations of Shock Compressed Quartz
Atomistic non-equilibrium molecular dynamics (NEMD) simulations of shock wave
compression of quartz have been performed using the so-called BKS
semi-empirical potential of van Beest, Kramer and van Santen to construct the
Hugoniot of quartz. Our scheme mimics the real world experimental set up by
using a flyer-plate impactor to initiate the shock wave and is the first shock
wave simulation that uses a geom- etry optimised system of a polar slab in a
3-dimensional system employing periodic boundary conditions. Our scheme also
includes the relaxation of the surface dipole in the polar quartz slab which is
an essential pre-requisite to a stable simulation. The original BKS potential
is unsuited to shock wave calculations and so we propose a simple modification.
With this modification, we find that our calculated Hugoniot is in good
agreement with experimental shock wave data up to 25 GPa, but significantly
diverges beyond this point. We conclude that our modified BKS potential is
suitable for quartz under representative pressure conditions of the Earth core,
but unsuitable for high-pressure shock wave simulations. We also find that the
BKS potential incorrectly prefers the {\beta}-quartz phase over the
{\alpha}-quartz phase at zero-temperature, and that there is a {\beta}
\rightarrow {\alpha} phase-transition at 6 GPa.Comment: 19 pages, 13 figures, Accepted for publication in Journal of Chemical
Physic
Inflammation and oxidative stress in multiple sclerosis:Consequences for therapy development
CNS inflammation is a major driver of MS pathology. Differential immune responses, including the adaptive and the innate immune system, are observed at various stages of MS and drive disease development and progression. Next to these immune-mediated mechanisms, other mediators contribute to MS pathology. These include immune-independent cell death of oligodendrocytes and neurons as well as oxidative stress-induced tissue damage. In particular, the complex influence of oxidative stress on inflammation and vice versa makes therapeutic interference complex. All approved MS therapeutics work by modulating the autoimmune response. However, despite substantial developments in the treatment of the relapsing-remitting form of MS, approved therapies for the progressive forms of MS as well as for MS-associated concomitants are limited and much needed. Here, we summarize the contribution of inflammation and oxidative stress to MS pathology and discuss consequences for MS therapy development
First-Order Melting and Dynamics of Flux Lines in a Model for YBaCuO
We have studied the statics and dynamics of flux lines in a model for YBCO,
using both Monte Carlo simulations and Langevin dynamics. For a clean system,
both approaches yield the same melting curve, which is found to be weakly first
order with a heat of fusion of about per vortex pancake at a
field of The time averaged magnetic field distribution
experienced by a fixed spin is found to undergo a qualitative change at
freezing, in agreement with NMR and experiments. Melting in the
clean system is accompanied by a proliferation of free disclinations which show
a clear B-dependent 3D-2D crossover from long disclination lines parallel to
the c-axis at low fields, to 2D ``pancake'' disclinations at higher fields.
Strong point pins produce a logarithmical relaxation which results from
slow annealing out of disclinations in disordered samples.Comment: 31 pages, latex, revtex, 12 figures available upon request, No major
changes to the original text, but some errors in the axes scale for Figures 6
and 7 were corrected(new figures available upon request), to be published in
Physical Review B, July 199
Role of modelling in improving nutrient efficiency in cropping systems
The applicability of models in addressing resource management issues in agriculture has been widely promoted by the research community, yet examples of real impacts of such modelling efforts on current farming practices are rare. Nevertheless, simulation models can compliment traditional field experimentation in researching alternative management options. The first objective of this paper is, therefore, to provide four case study examples of where models were used to help research issues relating to improved nutrient efficiency in low-input cropping systems. The first two cases addressed strategies of augmenting traditional farming practices with small applications of chemical fertilizer (N and P). The latter two cases explicitly addressed the question of what plant genetic traits can be beneficial in low-nutrient farming systems. In each of these case studies, the APSIM (Agricultural Production Systems Simulator) systems model was used to simulate the impacts of alternative crop management systems. The question of whether simulation models can assist the research community in contributing to purposeful change in farming practice is also addressed. Recent experiences in Australia are reported where simulation models have contributed to practice change by farmers. Finally, current initiatives aimed at testing whether models can also contribute to improving the nutrient efficiency of smallholder farmers in the SAT are discussed
Anthropogenic modifications to fire regimes in the wider SerengetiâMara ecosystem
Fire is a key driver in savannah systems and widely used as a land management tool. Intensifying human land uses are leading to rapid changes in the fire regimes, with consequences for ecosystem functioning and composition. We undertake a novel analysis describing spatial patterns in the fire regime of the SerengetiâMara ecosystem, document multidecadal temporal changes and investigate the factors underlying these patterns. We used MODIS active fire and burned area products from 2001 to 2014 to identify individual fires; summarizing four characteristics for each detected fire: size, ignition date, time since last fire and radiative power. Using satellite imagery, we estimated the rate of change in the density of livestock bomas as a proxy for livestock density. We used these metrics to model drivers of variation in the four fire characteristics, as well as total number of fires and total area burned. Fires in the SerengetiâMara show high spatial variabilityâwith number of fires and ignition date mirroring mean annual precipitation. The shortâterm effect of rainfall decreases fire size and intensity but cumulative rainfall over several years leads to increased standing grass biomass and fuel loads, and, therefore, in larger and hotter fires. Our study reveals dramatic changes over time, with a reduction in total number of fires and total area burned, to the point where some areas now experience virtually no fire. We suggest that increasing livestock numbers are driving this decline, presumably by inhibiting fire spread. These temporal patterns are part of a global decline in total area burned, especially in savannahs, and we caution that ecosystem functioning may have been compromised. Land managers and policy formulators need to factor in rapid fire regime modifications to achieve management objectives and maintain the ecological function of savannah ecosystems
Fertility, Living Arrangements, Care and Mobility
There are four main interconnecting themes around which the contributions in this book are based. This introductory chapter aims to establish the broad context for the chapters that follow by discussing each of the themes. It does so by setting these themes within the overarching demographic challenge of the twenty-first century â demographic ageing. Each chapter is introduced in the context of the specific theme to which it primarily relates and there is a summary of the data sets used by the contributors to illustrate the wide range of cross-sectional and longitudinal data analysed
Farmers, advisers and researchers learning together better management of crops and croplands
Summary. Farmers in the northeastern sub-tropics of Australia must cope with very high climatic variability in order to succeed in crop production. Their capacity for innovation was tapped by means of an on-farm research project that brought farmers, advisers and researchers together on the Darling Downs and in central Queensland. The researchers added value to the farmers' own experiments on fertility and water use efficiency by soil and weather monitoring at specific sites and then using a simulation model of cropping systems to extend findings to a wider context of climate and soil. The advisers extended knowledge aquired from this experience via local farmer networks and have undertaken training in the use of simulation to support farmers' management decisions. The experience described opens up possibilities for developing new, cost-effective ways for devising and testing improved farm management
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