8,685 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
Charge separation instability in an unmagnetized disk plasma around a Kerr black hole
In almost all of plasma theories for astrophysical objects, we have assumed
the charge quasi-neutrality of unmagnetized plasmas in global scales. This
assumption has been justified because if there is a charged plasma, it induces
electric field which attracts the opposite charge, and this opposite charge
reduces the charge separation. Here, we report a newly discovered instability
which causes a charge separation in a rotating plasma inside of an innermost
stable circular orbit (ISCO) around a black hole. The growth rate of the
instability is smaller than that of the disk instability even in the unstable
disk region and is forbidden in the stable disk region outside of the ISCO.
However, this growth rate becomes comparable to that of the disk instability
when the plasma density is much lower than a critical density inside of the
ISCO. In such case, the charge separation instability would become apparent and
cause the charged accretion into the black hole, thus charge the hole up.Comment: 15pages, 1 figur
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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
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
Literacy Text Selections in Secondary School Classrooms: Exploring the Practices of English Teachers as Agents of Change
The purpose of this paper is to examine how Ontario secondary school English teachers make choices about which literature to teach in their courses. This will be done in order to more deeply understand why many secondary school teachers may or may not encourage students to read contemporary, social issue texts. This paper uses a critical sociology of schooling theoretical perspective to critique the study\u27s findings. We examine the relation between policies and practice, the issue of resources and structural barriers, and how decisions are made around literary text choices. Some themes that emerged out of the interviews focus on a range of views expressed about personal agency, literary canons, gender, sexual orientation, and racism as central issues that shape text selection. We conclude by arguing for the need for policy to support individual teachers to take risks in their professional ability to select and teach contemporary social issues texts to high school students in all disciplines
Circular 109
Introduction -- Explanation of Plant Evaluation Tables -- Table 1. Weather records for the test years -- Table 2. All plant materials evaluated in 1996 -- Table 3. All plants that have been evaluated but did not survive the minimum number of test years -- Table 4. Plantings from 1996 that have not yet been evaluated for winter survival -- Table 5. Annual flowers evaluated in 1996 -- Appendix 1. Commercial Sources and Organizations -- Map of GB
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