8,960 research outputs found

    Theclinae of Rondonia, Brazil: Gigantorubra and Angulopis : with descriptions of new species (Lepidoptera: Lycaenidae)

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    The species of Gigantombra and Angulopis encountered in the Caca ulandia area of central Rondonia, Brazil, are reviewed. These include ten species (all new) of Gigantombra (G. microserrata, G. dl:vergens, G. quadramacula, G. ampla, G. fuscafascia, G. silva, G. rondonia, G. obscura, G. pelplexa, G. pUlpura) and one new species of Angulo pis (A. tenuis). Thecla sangala Hewitson (1868) is recognized as having priority over Theela autoelea Hewitson (1863-1878 [1877]), new synonym. Rondonia continues to appear as a center ofthecline endemism and to provide abundant examples of sibling species diversity

    Theclinae of Rondonia, Brazil: Strymon Hübner : with descriptions of new species (Lepidoptera: Lycaenidae)

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    Twenty-two species of Strymon are known from the vicinity of Cacaulandia in Rondonia, Brazil, of which 14 are new species. These belong to 5 species groups: the "oreala" group [Strymon megarus (Godart)]; the "ziba" group [Strymon ziba (Hewitson), Strymon thulia (Hewitson), Strymon spinatus new species, Strymon latamaculus new species, Strymon pallidulus new species, Stlymon tholus new species]; "valentina" group [Strymon rotundum new species]; "crossoea" group [Strymon crossoea (Hewitson), Strymon crambusa (Hewitson), Stlymon germana new species, Strymon novasignum new species, Strymon clavus new species, Strymon implexus new species, Strymon inmirum new species, Strymon incanus new species, Strymon faunalia (Hewitson), Strymon halos new species, Strymon conspergus new species, Strymon bazochii (Godart), Strymon diagonalis new species]; and "eurytulus" group [Strymon bubastus (Stoll)]. Tentative subgroups of species are suggested for the "crossoea" group as they occur in Rondonia. A neotype is designated for Tmolus basilides and the name synonymized with Strymon megarus. The "basilides" group of Johnson et al. (1990) is renamed the "ziba" group. Based on lectotype designations and superficial and genital differences, S. ziba and S. thu.lia are elevated to specific status

    Resolving Gas Flows in the Ultraluminous Starburst IRAS23365+3604 with Keck LGSAO/OSIRIS

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    Keck OSIRIS/LGSAO observations of the ultraluminous galaxy IRAS~23365+3604 resolve a circumnuclear bar (or irregular disk) of semimajor axis 0.42" (520 pc) in Paschen-alpha emission. The line-of-sight velocity of the ionized gas increases from the northeast toward the southwest; this gradient is perpendicular to the photometric major axis of the infrared emission. Two pairs of bends in the zero-velocity line are detected. The inner bend provides evidence for gas inflow onto the circumnuclear disk/bar structure. We interpret the gas kinematics on kiloparsec scales in relation to the molecular gas disk and multiphase outflow discovered previously. In particular, the fast component of the outflow (detected previously in line wings) is not detected, adding support to the conjecture that the fast wind originates well beyond the nucleus. These data directly show the dynamics of gas inflow and outflow in the central kiloparsec of a late-stage, gas-rich merger and demonstrate the potential of integral field spectroscopy to improve our understanding of the role of gas flows during the growth phase of bulges and supermassive black holes.Comment: 14 pages with 7 figures accepted to the astrophysical journa

    A tight coupling between β\u3csub\u3e2\u3c/sub\u3eY97 and β\u3csub\u3e2\u3c/sub\u3eF200 of the GABA\u3csub\u3eA\u3c/sub\u3e receptor mediates GABA binding

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    The GABAA receptor is an oligopentameric chloride channel that is activated via conformation changes induced upon the binding of the endogenous ligand, GABA, to the extracellular inter-subunit interfaces. Although dozens of amino acid residues at the α/β interface have been implicated in ligand binding, the structural elements that mediate ligand binding and receptor activation are not yet fully described. In this study, double-mutant cycle analysis was employed to test for possible interactions between several arginines (α1R67, α1R120, α1R132, and β2R207) and two aromatic residues (β2Y97 and β2F200) that are present in the ligand-binding pocket and are known to influence GABA affinity. Our results show that neither α1R67 nor α1R120 is functionally coupled to either of the aromatics, whereas a moderate coupling exists between α1R132 and both aromatic residues. Significant functional coupling between β2R207 and both β2Y97 and β2F200 was found. Furthermore, we identified an even stronger coupling between the two aromatics, β2Y97 and β2F200, and for the first time provided direct evidence for the involvement of β2Y97 and β2F200 in GABA binding. As these residues are tightly linked, and mutation of either has similar, severe effects on GABA binding and receptor kinetics, we believe they form a single functional unit that may directly coordinate GABA

    A simple formula for pooling knowledge about a quantum system

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    When various observers obtain information in an independent fashion about a classical system, there is a simple rule which allows them to pool their knowledge, and this requires only the states-of-knowledge of the respective observers. Here we derive an equivalent quantum formula. While its realm of applicability is necessarily more limited, it does apply to a large class of measurements, and we show explicitly for a single qubit that it satisfies the intuitive notions of what it means to pool knowledge about a quantum system. This analysis also provides a physical interpretation for the trace of the product of two density matrices.Comment: 5 pages, Revtex

    To boldly go:an occam-π mission to engineer emergence

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    Future systems will be too complex to design and implement explicitly. Instead, we will have to learn to engineer complex behaviours indirectly: through the discovery and application of local rules of behaviour, applied to simple process components, from which desired behaviours predictably emerge through dynamic interactions between massive numbers of instances. This paper describes a process-oriented architecture for fine-grained concurrent systems that enables experiments with such indirect engineering. Examples are presented showing the differing complex behaviours that can arise from minor (non-linear) adjustments to low-level parameters, the difficulties in suppressing the emergence of unwanted (bad) behaviour, the unexpected relationships between apparently unrelated physical phenomena (shown up by their separate emergence from the same primordial process swamp) and the ability to explore and engineer completely new physics (such as force fields) by their emergence from low-level process interactions whose mechanisms can only be imagined, but not built, at the current time
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