When does an ostrich become a bird? The role of typicality in early word comprehension

Which objects and animals are are children willing to accept as referents for words they know? To answer this question, the authors assessed early word comprehension using the preferential looking task. Children were shown 2 stimuli side by side (a target and a distractory) and heard the target stimulus named. The target stimulus was either a typical or an atypical exemplar of the named category. It was predicted that children first connect typical examples with the target name and broaden the extension of the name as they get older to include less typical examples. Experiment 1 shows that when targets are named, 12-month-olds display an increase in target looking for typical but not atypical targets whereas 24-month-olds display an increase for both. Experiment 2 shows that 18-month-old display a pattern similar to that of 24-month-olds. Implications for the early development of word comprehension are discussed

Fe I and Fe II Abundances of Solar-Type Dwarfs in the Pleiades Open Cluster

We have derived Fe abundances of 16 solar-type Pleiades dwarfs by means of an equivalent width analysis of Fe I and Fe II lines in high-resolution spectra obtained with the Hobby - Eberly Telescope and High Resolution Spectrograph. Abundances derived from Fe II lines are larger than those derived from Fe I lines (herein referred to as over-ionization) for stars with Teff < 5400 K, and the discrepancy (deltaFe = [Fe II/H] - [Fe I/H]) increases dramatically with decreasing Teff, reaching over 0.8 dex for the coolest stars of our sample. The Pleiades joins the open clusters M 34, the Hyades, IC 2602, and IC 2391, and the Ursa Major moving group, demonstrating ostensible over-ionization trends. The Pleiades deltaFe abundances are correlated with Ca II infrared triplet and Halpha chromospheric emission indicators and relative differences therein. Oxygen abundances of our Pleiades sample derived from the high-excitation O I triplet have been previously shown to increase with decreasing Teff, and a comparison with the deltaFe abundances suggests that the over-excitation (larger abundances derived from high excitation lines relative to low excitation lines) and over-ionization effects that have been observed in cool open cluster and disk field main sequence (MS) dwarfs share a common origin. Star-to-star Fe I abundances have low internal scatter, but the abundances of stars with Teff < 5400 K are systematically higher compared to the warmer stars. The cool star [Fe I/H] abundances cannot be connected directly to over-excitation effects, but similarities with the deltaFe and O I triplet trends suggest the abundances are dubious. Using the [Fe I/H] abundances of five stars with Teff > 5400 K, we derive a mean Pleiades cluster metallicity of [Fe/H] = +0.01 +/- 0.02.Comment: 32 pages, 7 figures, 7 tables; accepted by PAS

Assessing molecular outflows and turbulence in the protostellar cluster Serpens South

Molecular outflows driven by protostellar cluster members likely impact their surroundings and contribute to turbulence, affecting subsequent star formation. The very young Serpens South cluster consists of a particularly high density and fraction of protostars, yielding a relevant case study for protostellar outflows and their impact on the cluster environment. We combined CO $J=1-0$ observations of this region using the Combined Array for Research in Millimeter-wave Astronomy (CARMA) and the Institut de Radioastronomie Millim\'{e}trique (IRAM) 30 m single dish telescope. The combined map allows us to probe CO outflows within the central, most active region at size scales of 0.01 pc to 0.8 pc. We account for effects of line opacity and excitation temperature variations by incorporating $^{12}$CO and $^{13}$CO data for the $J=1-0$ and $J=3-2$ transitions (using Atacama Pathfinder Experiment and Caltech Submillimeter Observatory observations for the higher CO transitions), and we calculate mass, momentum, and energy of the molecular outflows in this region. The outflow mass loss rate, force, and luminosity, compared with diagnostics of turbulence and gravity, suggest that outflows drive a sufficient amount of energy to sustain turbulence, but not enough energy to substantially counter the gravitational potential energy and disrupt the clump. Further, we compare Serpens South with the slightly more evolved cluster NGC 1333, and we propose an empirical scenario for outflow-cluster interaction at different evolutionary stages.Comment: 26 pages, 15 figures, accepted for publication in the Astrophysical Journa

Lepidosperma prospectum (Cyperaceae), a new species from Sydney coastal heath and notes on usage of sword sedges

Lepidosperma prospectum G.T.Plunkett & R.L.Barrett (Cyperaceae tribe Schoeneae) is here described as a new species in the Sydney region of New South Wales. It is highly restricted in distribution, occurring at Manly (Sydney Harbour National Park), Kamay Botany Bay National Park and Royal National Park in dense coastal shrublands behind coastal cliffs. These locations are within the traditional lands of the Gamaragal, Gweagal and Dharawal people respectively. Joseph Banks and Daniel Solander were the first Europeans to explore the flora of New South Wales in 1770 around Botany Bay but they did not collect this species. Lepidosperma prospectum is superficially similar to L. sieberi Kunth, which occurs in adjacent habitats, but molecular data have shown that it is more closely allied to Western Australian species. A brief review of recorded indigenous and European knowledge and utilisation of the genus Lepidosperma Labill. is presented to highlight the varied uses of the genus

The Algebraic Bethe Ansatz and Tensor Networks

We describe the Algebraic Bethe Ansatz for the spin-1/2 XXX and XXZ Heisenberg chains with open and periodic boundary conditions in terms of tensor networks. These Bethe eigenstates have the structure of Matrix Product States with a conserved number of down-spins. The tensor network formulation suggestes possible extensions of the Algebraic Bethe Ansatz to two dimensions

Ownership Structure and Incentives to Invest: Dual-structured Irrigation Cooperatives in Australia

In the past decade, Australia has begun to privatize its irrigation system. Two general models have emerged: a single and a dual ownership structure. This paper examines the trade-offs, costs and benefits, and the attendant efficiencies regarding costs of ownership. In particular, we examine member capital investment incentives and resultant risk-bearing costs related to capital formation. The paper concludes that the dual ownership structure system has significant economic advantages relative to its single-structured counterpart

CARMA Large Area Star Formation Survey: Observational Analysis of Filaments in the Serpens South Molecular Cloud

We present the N2H+(J=1-0) map of the Serpens South molecular cloud obtained as part of the CARMA Large Area Star Formation Survey (CLASSy). The observations cover 250 square arcminutes and fully sample structures from 3000 AU to 3 pc with a velocity resolution of 0.16 km/s, and they can be used to constrain the origin and evolution of molecular cloud filaments. The spatial distribution of the N2H+ emission is characterized by long filaments that resemble those observed in the dust continuum emission by Herschel. However, the gas filaments are typically narrower such that, in some cases, two or three quasi-parallel N2H+ filaments comprise a single observed dust continuum filament. The difference between the dust and gas filament widths casts doubt on Herschel ability to resolve the Serpens South filaments. Some molecular filaments show velocity gradients along their major axis, and two are characterized by a steep velocity gradient in the direction perpendicular to the filament axis. The observed velocity gradient along one of these filaments was previously postulated as evidence for mass infall toward the central cluster, but these kind of gradients can be interpreted as projection of large-scale turbulence.Comment: 12 pages, 4 figures, published in ApJL (July 2014

Modeling non-stationary urban growth: The SPRAWL model and the ecological impacts of development

Urban development is a principal driver of landscape change affecting the integrity of ecological systems and the capacity of the landscape to support species. We developed an urban growth model (SPRAWL), evaluated it with hindcasting, and used it to simulate urban growth across the northeastern United States between 2010 and 2080 under four alternative scenarios. In the model, urban growth is constrained by demand for new development for each time step at the subregional scale. Demand is subsequently allocated to local application panes (5 km on a side within 15 km window) using a unique landscape context matching algorithm, such that the more historical development that occurred in the matched training windows the higher the proportion of future demand assigned to the pane. Lastly, demand in each pane is allocated among development types and then allocated to individual patches based on suitability surfaces unique to that landscape context. SPRAWL has a multi-level, multi-scale structure that captures urban growth drivers operating at multiple scales and, when combined with the unique matching and suitability algorithms, induces non-stationarity in urban growth across time and space. Our evaluation indicated that SPRAWL was highly discriminatory, well-calibrated, and highly predictive of new development, but performed weakly for redevelopment transitions. We evaluated the ecological impacts of four alternative urban growth scenarios varying in total demand for new development and “sprawliness” of new development relative to historical patterns using an ecological integrity index. The results were consistent with expectations and demonstrated the potential of SPRAWL for scenario analysis

What's the point of knowing how?

Why is it useful to talk and think about knowledge-how? Using Edward Craig’s discussion of the function of the concepts of knowledge and knowledge-how as a jumping off point, this paper argues that considering this question can offer us new angles on the debate about knowledge-how. We consider two candidate functions for the concept of knowledge-how: pooling capacities, and mutual reliance. Craig makes the case for pooling capacities, which connects knowledge-how to our need to pool practical capacities. I argue that the evidence is much more equivocal. My suggested diagnosis is that the concept of knowledge-how plays both functions, meaning that the concept of knowledge-how is inconsistent, and that the debate about knowledge-how is at least partly a metalinguistic negotiation. In closing, I suggest a way to revise the philosophical concept of knowledge how