1,998 research outputs found
When The Bells Of Love Are Ringing
https://digitalcommons.library.umaine.edu/mmb-vp/5065/thumbnail.jp
Tracking the associative boost in infancy.
Do words that are both associatively and taxonomically related prime each other in the infant mental lexicon? We explore the impact of these semantic relations in the emerging lexicon. Using the head-turn preference procedure, we show that 18-month-old infants have begun to construct a semantic network of associatively and taxonomically related words, such as dog-cat or apple-cheese. We demonstrate that priming between words is longer-lasting when the relationship is both taxonomic and associative, as opposed to purely taxonomic, reflecting the associative boost reported in the adult priming literature. Our results demonstrate that 18-month-old infants are able to construct a lexical-semantic network based on associative and taxonomic relations between words in the network, and that lexical-semantic links are more robust when they are both associative and taxonomic in character. Furthermore, the manner in which activation is propagated through the emerging lexical-semantic network appears to depend upon the type of semantic relation between words. We argue that 18-month-old infants have a mental lexicon that shares important structural and processing properties with that of the adult system
A Search for Ultra-High Energy Counterparts to Gamma-Ray Bursts
A small air shower array operating over many years has been used to search
for ultra-high energy (UHE) gamma radiation ( TeV) associated with
gamma-ray bursts (GRBs) detected by the BATSE instrument on the Compton
Gamma-Ray Observatory (CGRO). Upper limits for a one minute interval after each
burst are presented for seven GRBs located with zenith angles . A excess over background was observed between 10 and
20 minutes following the onset of a GRB on 11 May 1991. The confidence level
that this is due to a real effect and not a background fluctuation is 99.8\%.
If this effect is real then cosmological models are excluded for this burst
because of absorption of UHE gamma rays by the intergalactic radiation fields.Comment: 4 pages LaTeX with one postscript figure. This version does not use
kluwer.sty and will allow automatic postscript generatio
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
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
Impact of prematurity on long-stay paediatric intensive care unit admissions in England 2008-2018
BACKGROUND: Survival following extreme preterm birth has improved, potentially increasing the number of children with ongoing morbidity requiring intensive care in childhood. Previous single-centre studies have suggested that long-stay admissions in paediatric intensive care units (PICUs) are increasing. We aimed to examine trends in long-stay admissions (≥28 days) to PICUs in England, outcomes for this group (including mortality and PICU readmission), and to determine the contribution of preterm-born children to the long-stay population, in children aged <2 years. METHODS: Data was obtained from the Paediatric Intensive Care Audit Network (PICANet) for all children <2 years admitted to National Health Service PICUs from 1/1/2008 to 31/12/2018 in England. We performed descriptive analysis of child characteristics and PICU outcomes. RESULTS: There were 99,057 admissions from 67,615 children. 2,693 children (4.0%) had 3,127 long-stays. Between 2008 and 2018 the annual number of long-stay admissions increased from 225 (2.7%) to 355 (4.0%), and the proportion of bed days in PICUs occupied by long-stay admissions increased from 24.2% to 33.2%. Of children with long-stays, 33.5% were born preterm, 53.5% were born at term, and 13.1% had missing data for gestational age. A considerable proportion of long-stay children required PICU readmission before two years of age (76.3% for preterm-born children). Observed mortality during any admission was also disproportionately greater for long-stay children (26.5% for term-born, 24.8% for preterm-born) than the overall rate (6.3%). CONCLUSIONS: Long-stays accounted for an increasing proportion of PICU activity in England between 2008 and 2018. Children born preterm were over-represented in the long-stay population compared to the national preterm birth rate (8%). These results have significant implications for future research into paediatric morbidity, and for planning future PICU service provision
Global magnetohydrodynamic simulation of the 15 March 2013 coronal mass ejection event-Interpretation of the 30-80 MeV proton flux
The coronal mass ejection (CME) event on 15 March 2013 is one of the few solar events in Cycle 24 that produced a large solar energetic particle (SEP) event and severe geomagnetic activity. Observations of SEP from the ACE spacecraft show a complex time-intensity SEP profile that is not easily understood with current empirical SEP models. In this study, we employ a global three-dimensional (3-D) magnetohydrodynamic (MHD) simulation to help interpret the observations. The simulation is based on the H3DMHD code and incorporates extrapolations of photospheric magnetic field as the inner boundary condition at a solar radial distance (r) of 2.5 solar radii. A Gaussian-shaped velocity pulse is imposed at the inner boundary as a proxy for the complex physical conditions that initiated the CME. It is found that the time-intensity profile of the high-energy (>10 MeV) SEPs can be explained by the evolution of the CME-driven shock and its interaction with the heliospheric current sheet and the nonuniform solar wind. We also demonstrate in more detail that the simulated fast-mode shock Mach number at the magnetically connected shock location is well correlated (r_(cc) ≥ 0.7) with the concurrent 30–80 MeV proton flux. A better correlation occurs when the 30–80 MeV proton flux is scaled by r^(−1.4)(r_(cc) = 0.87). When scaled by r^(−2.8), the correlation for 10–30 MeV proton flux improves significantly from r_(cc) = 0.12 to r_(cc) = 0.73, with 1 h delay. The present study suggests that (1) sector boundary can act as an obstacle to the propagation of SEPs; (2) the background solar wind is an important factor in the variation of IP shock strength and thus plays an important role in manipulation of SEP flux; (3) at least 50% of the variance in SEP flux can be explained by the fast-mode shock Mach number. This study demonstrates that global MHD simulation, despite the limitation implied by its physics-based ideal fluid continuum assumption, can be a viable tool for SEP data analysis
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