We investigated whether learning an artificial language at 17 months was predictive of children's natural language vocabulary and grammar skills at 54 months. Children at 17 months listened to an artificial language containing non-adjacent dependencies, and were then tested on their learning to segment and to generalise the structure of the language. At 54 months, children were then tested on a range of standardised natural language tasks that assessed receptive and expressive vocabulary and grammar.
View Article and Find Full Text PDFThere is a wealth of evidence demonstrating that executive function (EF) abilities are positively associated with language development during the preschool years, such that children with good executive functions also have larger vocabularies. However, why this is the case remains to be discovered. In this study, we focused on the hypothesis that sentence processing abilities mediate the association between EF skills and receptive vocabulary knowledge, in that the speed of language acquisition is at least partially dependent on a child's processing ability, which is itself dependent on executive control.
View Article and Find Full Text PDFHow do language learners avoid the production of verb argument structure overgeneralization errors ( c.f. ), while retaining the ability to apply such generalizations productively when appropriate? This question has long been seen as one that is both particularly central to acquisition research and particularly challenging.
View Article and Find Full Text PDFAll accounts of language acquisition agree that, by around age 4, children's knowledge of grammatical constructions is abstract, rather than tied solely to individual lexical items. The aim of the present research was to investigate, focusing on the passive, whether children's and adults' performance is additionally semantically constrained, varying according to the distance between the semantics of the verb and those of the construction. In a forced-choice pointing study (Experiment 1), both 4- to 6-year olds (N = 60) and adults (N = 60) showed support for the prediction of this semantic construction prototype account of an interaction such that the observed disadvantage for passives as compared to actives (i.
View Article and Find Full Text PDFChildren with ASD and an IQ-matched control group of typically developing (TD) children completed an elicited-production task which encouraged the production of reversible passive sentences (e.g., "Bob was hit by Wendy").
View Article and Find Full Text PDFTo acquire language, infants must learn how to identify words and linguistic structure in speech. Statistical learning has been suggested to assist both of these tasks. However, infants' capacity to use statistics to discover words and structure together remains unclear.
View Article and Find Full Text PDFIt is becoming increasingly clear that the way that children acquire cognitive representations depends critically on how their processing system is developing. In particular, recent studies suggest that individual differences in language processing speed play an important role in explaining the speed with which children acquire language. Inconsistencies across studies, however, mean that it is not clear whether this relationship is causal or correlational, whether it is present right across development, or whether it extends beyond word learning to affect other aspects of language learning, like syntax acquisition.
View Article and Find Full Text PDFTo explain the phenomenon that certain English verbs resist passivization (e.g., *£5 was cost by the book), Pinker (1989) proposed a semantic constraint on the passive in the adult grammar: The greater the extent to which a verb denotes an action where a patient is affected or acted upon, the greater the extent to which it is compatible with the passive.
View Article and Find Full Text PDFParticipants aged 5;2-6;8, 9;2-10;6 and 18;1-22;2 (72 at each age) rated verb argument structure overgeneralization errors (e.g., *Daddy giggled the baby) using a five-point scale.
View Article and Find Full Text PDFWhilst some locative verbs alternate between the ground- and figure-locative constructions (e.g. Lisa sprayed the flowers with water/Lisa sprayed water onto the flowers), others are restricted to one construction or the other (e.
View Article and Find Full Text PDFWiley Interdiscip Rev Cogn Sci
January 2013
Unlabelled: This review investigates empirical evidence for different theoretical proposals regarding the retreat from overgeneralization errors in three domains: word learning (e.g., *doggie to refer to all animals), morphology [e.
View Article and Find Full Text PDFAntimicrob Agents Chemother
February 2013
GS-9669 is a highly optimized thumb site II nonnucleoside inhibitor of the hepatitis C virus (HCV) RNA polymerase, with a binding affinity of 1.35 nM for the genotype (GT) 1b protein. It is a selective inhibitor of HCV RNA replication, with a mean 50% effective concentration (EC(50)) of ≤ 11 nM in genotype 1 and 5 replicon assays, but lacks useful activity against genotypes 2 to 4.
View Article and Find Full Text PDFI am a third-year student on my last placement and due to qualify in four weeks. Colleagues from the ward have been asking me where I am going to work after I qualify. When I tell them that I am going to work on a ward for older people their reactions have varied from disbelief to horror.
View Article and Find Full Text PDFDrug Metab Dispos
July 2000
The metabolism of [2-acetyl-(14)C]oseltamivir (GS4104, Ro 64-0796), the prodrug of the novel influenza neuraminidase inhibitor GS4071 (Ro 64-0802), was examined in rats after oral dosing. Intact oseltamivir was observed only in lung and urine, accounting for 37 and 15% of the total radioactivity in these samples, respectively. GS4071 was the major metabolite in plasma, tissues, and urine, and accounted for 32 to 56% of the radioactivity present in these samples.
View Article and Find Full Text PDFJ Pharm Biomed Anal
April 1998
Cidofovir is an acyclic nucleotide analog with potent and broad-spectrum antiviral activity against adenoviruses and herpesviruses including cytomegalovirus (CMV). Cidofovir undergoes intracellular phosphorylation by host enzymes to cidofovir phosphate and cidofovir diphosphate (the active form). An unidentified metabolite has been observed previously in rat tissues and in urine of rabbits, rats and monkeys dosed with cidofovir.
View Article and Find Full Text PDFGS4071 is a novel potent inhibitor of influenza neuraminidase (Ki < 1 nM) with low (< 5%) oral bioavailability in animals. An ethyl ester prodrug of GS4071, GS4104, has exhibited good oral bioavailability in rat, mouse, and dog models and is currently being developed for the treatment of influenza A and B virus infections. Since influenza virus replicates primarily in the surface epithelial cells of the respiratory tract, the ability of the prodrug to deliver GS4071 to the bronchoalveolar lining fluid (BALF) following an oral dose of GS4104 should be an important indicator of its potential efficacy.
View Article and Find Full Text PDFThe oral bioavailability of PMEA [9-[2-(phosphonomethoxy)ethyl]adenine; adefovir) has been determined in rats from three bisester prodrugs of PMEA: bis-(pivaloyloxymethyl) PMEA (bis-POM PMEA), bis-(phenyl) PMEA, and bis-(o-ethoxyphenyl) PMEA. The prodrugs were each administered to 9 male rats as solutions in PEG 400 at a dose of 10 mg-equivalent of PMEA per kg. Plasma samples were obtained over the course of 12 hr and concentrations of PMEA were determined by fluorescence derivatization and analysis by HPLC.
View Article and Find Full Text PDFThe pharmacokinetics, distribution, and metabolism of [14C]cidofovir and its cyclic analog {[2-14C]-1-[((S)-2-hydroxy-2-oxo-1,4, 2-dioxaphosphorinan-5-yl)methyl]cytosine; [14C]cyclic HPMPC} were compared after administration to Sprague-Dawley rats. After intravenous (iv) administration of [14C]cidofovir (3 or 5 mg/kg) or [14C]cyclic HPMPC (5 mg/kg), plasma concentrations of total radioactivity declined in a multiexponential manner for both drugs with terminal half-lives of 7-11 hr. No metabolites of cidofovir were observed in plasma.
View Article and Find Full Text PDFFour hundred and four dogs from 9 pounds in Sydney were examined for circulating microfilariae and antigens of Dirofilaria immitis. One hundred of these were also examined post mortem for adult heartworms. The prevalence of infection in the 404 dogs as shown by serology was 11.
View Article and Find Full Text PDFControversy and ambiguity in the literature concerning the corneal penetration of prednisolone acetate over Prednisolone Sodium phosphate in NZW rabbits has recently prompted comparative studies using specific chromatographic assays. In vitro, corneal penetration studies were performed using the Ussing Chambers to compare the permeability and flux of both esters and prednisolone at 0.5% using a reversed phase HPLC-UV assay.
View Article and Find Full Text PDFPrednisolone, prednisolone acetate and prednisolone sodium phosphate are glucocorticoids used for ocular, anti-inflammatory therapy. A reversed-phase high-performance liquid chromatographic assay using ultraviolet detection has been developed that affords baseline resolution of the above analytes in balanced salt solutions and rabbit aqueous humor. The drugs can be quantified at 0.
View Article and Find Full Text PDFComparative corneal penetration studies in the literature with prednisolone sodium phosphate solution and prednisolone acetate suspension administered to rabbit eyes give conflicting results concerning the greater bioavailability of prednisolone acetate. A recent in vitro penetration study shows similar fluxes for both salt forms in terms of prednisolone, quantified by a specific HPLC assay. An in vivo comparison has been conducted in NZW rabbit eyes and shows similar bioavailability for both drugs.
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