8,525 research outputs found
The origin of the strings in the outer regions of Eta Carinae
The narrow optical filaments (`strings' or `spikes') emerging from the
Homunculus of Eta Carinae are modelled as resulting from the passage of
ballistic `bullets' of material through the dense circumstellar environment. In
this explanation, the string is the decelerating flow of ablated gas from the
bullet. An archive HST image and new forbidden line profiles of the most
distinct of the strings are presented and discussed in terms of this simple
model.Comment: 5 pages, 4 figure
Occupy: 'struggles for the common or an 'anti-politics of dignity? Reflections on Hardt and Negri and John Holloway
This article provides a critical examination of Michael Hardt and Antonio Negri’s and John Holloway’s theory of revolutionary subjectivity, and does so by applying their theories to the Occupy movement of 2011. Its central argument is that one should avoid collapsing ‘autonomist’ and ‘open’ Marxism, for whilst both approaches share Tronti’s (1979) insistence on the constituent role of class struggle, and also share an emphasis on a prefigurative politics which engages a non-hierarchical and highly participatory politics, there nevertheless remain some significant differences between their approaches. Ultimately, when applied to Occupy Movement whilst their theory isn’t entirely unproblematic, I will argue that Hardt and Negri’s ‘autonomist’ approach offers the stronger interpretation, due mainly to their revised historical materialism
HOW BIG IS YOUR NEIGHBORHOOD? SPATIAL IMPLICATIONS OF MARKET PARTICIPATION BY SMALLHOLDER LIVESTOCK PRODUCERS
Identifying ways to increase market participation by smallholder producers requires identifying variables that influence market access. This is usually achieved using probit estimation. An important phenomenon affecting entry decision-making is the entry decision of a 'similar' household, where similarity is measured in terms of 'location.' When neighborhood influences are significant, it is important to allow for them in discrete decision contexts, such as probit estimation. This paper, therefore, assesses the magnitude of neighborhood influences in smallholder decisions concerning market entry. The empirical model is based on a cross-section of (110) farms situated in northern Philippines, visited (twice) in the 2000-2001 production year (a panel of 220 observations). The vehicle for analysis is a Bayesian formulation of a standard probit model, but one that allows for spatial autoregression in the decision vector. Estimation requires a Metropolis-step addition to a basic Gibbs sampling algorithm and generates useful insights concerning quantities that are important for market-access policy.Livestock Production/Industries,
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'Open Marxism' against and beyond the 'Great Enclosure'? Reflections on How (Not) to Crack Capitalism
The main purpose of this article is to provide an in-depth discussion of John Holloway’s recent book, Crack Capitalism. To this end, the paper offers a detailed account of the key strengths and weaknesses of Holloway’s version of ‘open Marxism’. The analysis is divided into two parts. The first part focuses on six significant strengths of Crack Capitalism: (1) its insistence upon the importance of autonomous forms of agenda-setting for both individual and collective emancipation; (2) its emphasis on the ordinary constitution of social struggles; (3) its fine-grained interpretation of the socio-ontological conditions underlying human agency; (4) its processual conception of radical social transformation; (5) its recognition of the elastic, adaptable, and integrative power of capitalism; and (6) its proposal for an alternative critical theory, commonly known as ‘open Marxism’ or ‘autonomous Marxism’. The second part of the study examines the principal weaknesses of Crack Capitalism: (1) the counterproductive implications of the preponderance of negativity, owing to a one-sided concern with critique, cracks, and crises; (2) conceptual vagueness; (3) an overuse of poetic and metaphorical language; (4) the absence of a serious engagement with the question of normativity; (5) a lack of substantive evidence; (6) a residual economic reductionism; (7) a simplistic notion of gender; (8) the continuing presence of various problematic ‘isms’; (9) the misleading distinction between ‘doing’ and ‘labour’; (10) a reductive understanding of capitalism; (11) an unrealistic view of society; and (12) socio-ontological idealis
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REview of WOMEN, WORK AND THE LABOUR MOVEMENT IN AUSTRALIA AND AOTEAROA/NEW ZEALAND and MULTINATIONAL BANKS AND THEIR SOCIAL AND LABOUR PRACTICE
The Lore of Low Methane Livestock:Co-Producing Technology and Animals for Reduced Climate Change Impact
Methane emissions from sheep and cattle production have gained increasing profile in the context of climate change. Policy and scientific research communities have suggested a number of technological approaches to mitigate these emissions. This paper uses the concept of co-production as an analytical framework to understand farmers’ evaluation of a 'good animal’. It examines how technology and sheep and beef cattle are co-produced in the context of concerns about the climate change impact of methane. Drawing on 42 semi-structured interviews, this paper demonstrates that methane emissions are viewed as a natural and integral part of sheep and beef cattle by farmers, rather than as a pollutant. Sheep and beef cattle farmers in the UK are found to be an extremely heterogeneous group that need to be understood in their specific social, environmental and consumer contexts. Some are more amenable to appropriating methane reducing measures than others, but largely because animals are already co-constructed from the natural and the technical for reasons of increased production efficiency
IRAS04210+0400: Modeling the optical spectra from flaring large scale jets
The emission-lines in the active galaxy IRAS\,0421+0400 show a dramatic
(\,900\kms) increase in the velocity spread at the position of radio
hot-spots which are located at the beginning of extended radio lobes. We study
a simple geometric model of an opening outflow which reproduces the structure
found in the long-slit emission-line spectrum of the hot-spot regions. The
predicted bifurcations in the optical image structure of these regions is
confirmed by deep \oiii\,line-imaging. We propose that this phenomenon is the
result of a jet emerging from the galaxy through the boundary between the
interstellar and intergalactic medium. A similar model has previously been
suggested as an explanation for wide angle tail radio sources (WAT's). If our
model proves to be correct in more detailed future observations, then
IRAS\,0421+0400 provides a unique possibility to study the flaring jet
phenomenon at optical wavelengths.Comment: LaTeX (MN style-file), 10 pages, accepted by MNRAS, available online
at http://axp2.ast.man.ac.uk:8000/Preprints.htm
The Origin of X-shaped Radio Galaxies: Clues from the Z-symmetric Secondary Lobes
Existing radio images of a few X-shaped radio galaxies reveal Z-symmetric
morphologies in their weaker secondary lobes which cannot be naturally
explained by either the galactic merger or radio-lobe backflow scenarios, the
two dominant models for these X-shaped radio sources. We show that the merger
picture can explain these morphologies provided one takes into account that,
prior to the coalescence of their supermassive black holes, the smaller galaxy
releases significant amounts of gas into the ISM of the dominant active galaxy.
This rotating gas, whose angular momentum axis will typically not be aligned
with the original jets, is likely to provide sufficient ram pressure at a
distance ~10 kpc from the nucleus to bend the extant jets emerging from the
central engine, thus producing a Z-symmetry in the pair of radio lobes. Once
the two black holes have coalesced some 10^7 yr later, a rapid reorientation of
the jets along a direction close to that of the orbital angular momentum of the
swallowed galaxy relative to the primary galaxy would create the younger
primary lobes of the X-shaped radio galaxy. This picture naturally explains why
such sources typically have powers close to the FR I/II break. We suggest that
purely Z-symmetric radio sources are often en route to coalescence and the
concomitant emission of substantial gravitational radiation, while X-shaped
ones have already merged and radiated.Comment: 12 pages, 1 compressed figure; accepted for publication in ApJ
Letter
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