377 research outputs found
Intergalactic Globular Clusters
We confirm and extend our previous detection of a population of intergalactic
globular clusters in Abell 1185, and report the first discovery of an
intergalactic globular cluster in the nearby Virgo cluster of galaxies. The
numbers, colors and luminosities of these objects can place constraints on
their origin, which in turn may yield new insights to the evolution of galaxies
in dense environments.Comment: 2 pages, no figures. Talk presented at JD6, IAU General Assembly XXV,
Sydney, Australia, July 2003, to appear in Highlights of Astronomy, Vol. 1
Discrete Multiscale Analysis: A Biatomic Lattice System
We discuss a discrete approach to the multiscale reductive perturbative
method and apply it to a biatomic chain with a nonlinear interaction between
the atoms. This system is important to describe the time evolution of localized
solitonic excitations. We require that also the reduced equation be discrete.
To do so coherently we need to discretize the time variable to be able to get
asymptotic discrete waves and carry out a discrete multiscale expansion around
them. Our resulting nonlinear equation will be a kind of discrete Nonlinear
Schr\"odinger equation. If we make its continuum limit, we obtain the standard
Nonlinear Schr\"odinger differential equation
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The cultural grammar of governance: The UK Code of Corporate Governance, reflexivity, and the limits of 'soft' regulation
We identify limits of ‘reflexive governance’ by examining the UK Code of Corporate Governance that is celebrated for its ‘reflexivity’. By placing the historical genesis of the Code within its politico-economic context, it is shown how its scope and penetration is impeded by a shallow, ‘single loop’ of reflexivity. Legitimized by agency theory, the Code is infused by a ‘cultural grammar’ that perpetuates relations of shareholder primacy as it restricts accountability to narrow forms of information disclosure directed exclusively at shareholders. Engagement of a deeper, ‘double loop’ reflexivity allows account to be taken of the historical conditions and theoretical conceptions that shape practices and outcomes of corporate governance. Only then is it possible to disclose, challenge and reform narrow conceptions, boundaries and workings of ‘reflexive governance’
The ground state of the carbon atom in strong magnetic fields
The ground and a few excited states of the carbon atom in external uniform
magnetic fields are calculated by means of our 2D mesh Hartree-Fock method for
field strengths ranging from zero up to 2.35 10^9 T. With increasing field
strength the ground state undergoes six transitions involving seven different
electronic configurations which belong to three groups with different spin
projections S_z=-1,-2,-3. For weak fields the ground state configuration arises
from the field-free 1s^2 2s^2 2p_0 2p_{-1}, S_z=-1 configuration. With
increasing field strength the ground state involves the four S_z=-2
configurations 1s^22s2p_0 2p_{-1}2p_{+1}, 1s^22s2p_0 2p_{-1}3d_{-2}, 1s^22p_0
2p_{-1}3d_{-2}4f_{-3} and 1s^22p_{-1}3d_{-2}4f_{-3}5g_{-4}, followed by the two
fully spin polarized S_z=-3 configurations 1s2p_02p_{-1}3d_{-2}4f_{-3}5g_{-4}
and 1s2p_{-1}3d_{-2}4f_{-3}5g_{-4}6h_{-5}. The last configuration forms the
ground state of the carbon atom in the high field regime \gamma>18.664. The
above series of ground state configurations is extracted from the results of
numerical calculations for more than twenty electronic configurations selected
due to some general energetical arguments.Comment: 6 figures,acc. Phys.Rev.
Sushi in the United States, 1945-1970
Sushi first achieved widespread popularity in the United States in
the mid-1960s. Many accounts of sushi’s US establishment foreground
the role of a small number of key actors, yet underplay
the role of a complex web of large-scale factors that provided the
context in which sushi was able to flourish. This article critically
reviews existing literature, arguing that sushi’s US popularity
arose from contingent, long-term, and gradual processes. It examines
US newspaper accounts of sushi during 1945–1970, which
suggest the discursive context for US acceptance of sushi was
considerably more propitious than generally acknowledged.
Using California as a case study, the analysis also explains
conducive social and material factors, and directs attention to
the interplay of supply- and demand-side forces in the favorable
positioning of this “new” food. The article argues that the US
establishment of sushi can be understood as part of broader
public acceptance of Japanese cuisine
Wnt signaling in triple-negative breast cancer
Wnt signaling regulates a variety of cellular processes, including cell fate, differentiation, proliferation and stem cell pluripotency. Aberrant Wnt signaling is a hallmark of many cancers. An aggressive subtype of breast cancer, known as triple-negative breast cancer (TNBC), demonstrates dysregulation in canonical and non-canonical Wnt signaling. In this review, we summarize regulators of canonical and non-canonical Wnt signaling, as well as Wnt signaling dysfunction that mediates the progression of TNBC. We review the complex molecular nature of TNBC and the emerging therapies that are currently under investigation for the treatment of this disease
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