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PS49. Shifted Circadian Phase in Manic Episode was Returned to Normal after Treatment in Bipolar Disorder
Bipolar Proof Nets for MALL
In this work we present a computation paradigm based on a concurrent and
incremental construction of proof nets (de-sequentialized or graphical proofs)
of the pure multiplicative and additive fragment of Linear Logic, a resources
conscious refinement of Classical Logic. Moreover, we set a correspon- dence
between this paradigm and those more pragmatic ones inspired to transactional
or distributed systems. In particular we show that the construction of additive
proof nets can be interpreted as a model for super-ACID (or co-operative)
transactions over distributed transactional systems (typi- cally,
multi-databases).Comment: Proceedings of the "Proof, Computation, Complexity" International
Workshop, 17-18 August 2012, University of Copenhagen, Denmar
Binary planetary nebulae nuclei towards the Galactic bulge. II. A penchant for bipolarity and low-ionisation structures
Considerable effort has been applied towards understanding the precise
shaping mechanisms responsible for the diverse range of morphologies exhibited
by planetary nebulae (PNe). A binary companion is increasingly gaining support
as a dominant shaping mechanism, however morphological studies of the few PNe
that we know for certain were shaped by binary evolution are scarce or biased.
Newly discovered binary central stars (CSPN) from the OGLE-III photometric
variability survey have significantly increased the sample of post
common-envelope (CE) nebulae available for morphological analysis. We present
Gemini South narrow-band images for most of the new sample to complement
existing data in a qualitative morphological study of 30 post-CE nebulae.
Nearly 30% of nebulae have canonical bipolar morphologies, however this rises
to 60% once inclination effects are incorporated with the aid of geometric
models. This is the strongest observational evidence yet linking CE evolution
to bipolar morphologies. A higher than average proportion of the sample shows
low-ionisation knots, filaments or jets suggestive of a binary origin. These
features are also common around emission-line nuclei which may be explained by
speculative binary formation scenarios for H-deficient CSPN.Comment: Accepted for publication in A&
Extended shells around B[e] stars - implications for B[e] star evolution
Aims. The position of B[e] stars in the upper left part of the Hertzsprung-Russell diagram creates a quandary. Are these stars young stars evolving onto the main sequence or old stars that are evolving off of it? Spectral characteristics suggest that B[e] stars can be
placed into five subclasses and are not a homogeneous set. Such sub-classification is believed to coincide with varying origins and different evolutions. However, the evolutionary connection of B[e] stars – and notably sgB[e] – to other stars is unclear, particularly to evolved massive stars. We attempt to provide insight into the evolutionary past of B[e] stars.
Methods. We performed an Hα narrow-band CCD imaging survey of B[e] stars, in the northern hemisphere. Prior to the current work, no emission-line survey of B[e] stars had yet been made, while only two B[e] stars appeared to have a shell nebula as seen in the Digital Sky Survey. Of nebulae around B[e] stars, only the ring nebula around MWC137 has been previously observed extensively.
Results. In this presentation we report the findings from our narrow-band optical imaging survey of the environments of 25 B[e] stars. Of the objects surveyed, 7 show bipolar or uni- polar structures up to 15' across; 5 show faint, large, or filamentary shells; and 2 are compact planetary nebula-type systems. The most spectacular system observed is a large bipolar structure associated with MWC314.
Conclusions. The possible links between B[e] stars and other evolved stars, implied by our observations, are investigated
Bipolarity and Ambivalence in Landscape Architecture
Our discipline of landscape architecture contains bipolarity, not only in terms of landscape and architecture but also because the idea of landscape is both aesthetic and scientific. Furthermore, within landscape architecture there is a gap between design (as implied by architecture) and planning (implying land-use plan and policy orientation) on one hand, and a similar gap between design (associated with artistic activity, concerned with aesthetics as well as science) and research (considered as scientific activity Landscape architects often retain as much ambivalence between design and planning, as they do between design and research
Space Telescope Imaging Spectrograph slitless observations of Small Magellanic Cloud Planetary Nebulae: a study on morphology, emission line intensity, and evolution
A sample of 27 Planetary Nebulae (PNs) in the Small Magellanic Clouds (SMC)
have been observed with the Hubble Space Telescope Imaging Spectrograph
(HST/STIS) to determine their morphology, size, and the spatial variation of
the ratios of bright emission lines. The morphologies of SMC PNs are similar to
those of LMC and Galactic PNs. However, only a third of the resolved SMC PNs
are asymmetric, compared to half in the LMC. The low metallicity environment of
the SMC seems to discourage the onset of bipolarity in PNs. We measured the
line intensity, average surface brightness (SB), and photometric radius of each
nebula in halpha, hbeta, [O III] lambda4959 and 5007, [NII] 6548 and 6584, [S
II] lambda6716 and 5731, He I 6678, and [OI] 6300 and 6363. We show that the
surface brightness to radius relationship is the same as in LMC PNs, indicating
its possible use as a distance scale indicator for Galactic PNs. We determine
the electron densities and the ionized masses of the nebulae where the [S II]
lines were measured accurately, and we find that the SMC PNs are denser than
the LMC PNs by a factor of 1.5. The average ionized mass of the SMC PNs is 0.3
Msun. We also found that the median [O III]/hbeta intensity ratio in the SMC is
about half than the corresponding LMC median. We use Cloudy to model the
dependence of the [O III]/hbeta ratio on the oxygen abundance. Our models
encompass very well the average observed physical quantities. We suggest that
the SMC PNs are principally cooled by the carbon lines, making it hard to study
their excitation based on the optical lines at our disposal.Comment: Accepted for publication in the Astrophysical Journal, 30 pages, 13
figures, 6 tables. For high resolution version of Figs 1 to 6, see
http://archive.stsci.edu/hst/mcpn/home.htm
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