20 research outputs found
Governing access to gold in Ghana: In-depth geopolitics on mining concessions
Global Challenges (FSW
Atmospheric Heating and Wind Acceleration: Results for Cool Evolved Stars based on Proposed Processes
A chromosphere is a universal attribute of stars of spectral type later than
~F5. Evolved (K and M) giants and supergiants (including the zeta Aurigae
binaries) show extended and highly turbulent chromospheres, which develop into
slow massive winds. The associated continuous mass loss has a significant
impact on stellar evolution, and thence on the chemical evolution of galaxies.
Yet despite the fundamental importance of those winds in astrophysics, the
question of their origin(s) remains unsolved. What sources heat a chromosphere?
What is the role of the chromosphere in the formation of stellar winds? This
chapter provides a review of the observational requirements and theoretical
approaches for modeling chromospheric heating and the acceleration of winds in
single cool, evolved stars and in eclipsing binary stars, including physical
models that have recently been proposed. It describes the successes that have
been achieved so far by invoking acoustic and MHD waves to provide a physical
description of plasma heating and wind acceleration, and discusses the
challenges that still remain.Comment: 46 pages, 9 figures, 1 table; modified and unedited manuscript;
accepted version to appear in: Giants of Eclipse, eds. E. Griffin and T. Ake
(Berlin: Springer
Phenomenology of the Lense-Thirring effect in the Solar System
Recent years have seen increasing efforts to directly measure some aspects of
the general relativistic gravitomagnetic interaction in several astronomical
scenarios in the solar system. After briefly overviewing the concept of
gravitomagnetism from a theoretical point of view, we review the performed or
proposed attempts to detect the Lense-Thirring effect affecting the orbital
motions of natural and artificial bodies in the gravitational fields of the
Sun, Earth, Mars and Jupiter. In particular, we will focus on the evaluation of
the impact of several sources of systematic uncertainties of dynamical origin
to realistically elucidate the present and future perspectives in directly
measuring such an elusive relativistic effect.Comment: LaTex, 51 pages, 14 figures, 22 tables. Invited review, to appear in
Astrophysics and Space Science (ApSS). Some uncited references in the text
now correctly quoted. One reference added. A footnote adde
Transforming matters: sustaining gold lifeways in artisanal and small-scale mining
Growth strategies in mining regions promote gold extraction basedonindustrial mining, associating Artisanal and Small-scale Gold Mining (ASGM) with persistent informality. Against this background, we consider how to approach transformations to sustainability in ASGM. Acknowledging how problematic this topic is for sustainability debates,given howASGM is associated with a host of environmental and social problems,we argue that a justice lens demands we confront such challenges within the global politics of sustainability. This leads us to review advances inthe study of ASGM, linked to debates on extractivism, resource materialities, and informality. We use the notion of gold lifeways to capture how the matter of mining shapes different worlds of extraction. We argue that consideration of the potential for transformations to sustainability needs to be grounded within the realities of ASGM. This necessitates giving value to minersâ knowledge(s), perspectives and interests, while recognising the plurality of mining futures. Nevertheless, we conclude that between the immediacy of precarious work and the structural barriers to change in ASGM, the challenges for transformation cannot be underestimated.NWOGlobal Challenges (FSW
ReïŹning and regaining skills in ïŹxation/diversiïŹcation stage performers: The Five-A Model
Technical change is one of many factors underpinning success in elite, fixation/diversification stage performers. Surprisingly, however, there is a dearth of research pertaining to this process or the most efficacious methods used to bring about such a change. In this paper we highlight the emergent processes, yet also the lack in mechanistic comprehension surrounding technical change, addressing issues within the motor control, sport psychology, coaching and choking literature. More importantly, we seek an understanding of how these changes can be made more secure to competitive pressure, and how this can be embedded within the process of technical change. Following this review, we propose The Five-A Model based on successful coaching techniques, psychosocial concomitants, the avoidance of choking and principles of effective behaviour change. Specific mechanisms for each stage are discussed, with a focus on the use of holistic rhythm-based cues as a possible way of internalising changes. Finally, we suggest the need for further research to examine these five stages, to aid a more comprehensive construction of the content and delivery of such a programme within the applied setting
'We have so many challengesâ: smallâscale mining, Covidâ19 and constant interruptions in West Africa
Currently, the impacts of Covid-19 are receiving significant global attention. This also applies to the extractive industries, where this global crisis is directing the gaze of policymakers, donors and academics alike. Covid-19 is seen as having far-reaching and disruptive consequences, especially in the case of artisanal and small-scale mining. While the authors consider this attention important, their work on artisanal and small-scale mining in Ghana â and West Africa more broadly â reveals that for many miners, Covid-19 is âjustâ another interruption to their lives and lifeworlds which are chronically affected by interruptions of different scales, magnitudes and temporalities. As anthropologists have shown, foregrounding this structural condition â which is emblematic for the lives of many people, especially in the Global South â is key to questioning, understanding and contextualizing the current moment of âglobalâ crisis and must be an element of any policy and research emerging from it.Global Challenges (FSW
Mining âwasteâ: repurposing residues in artisanal and small-scale gold mining
NWOGlobal Challenges (FSW