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1.
Lang Speech ; : 238309231177884, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403367

RESUMO

Phrasal prosody is often viewed as a level of linguistic representation at which the phonetic profile of an utterance varies independently of the lexical items it contains. For example, the same word, when produced at the edges of prosodic phrases, will take longer to produce than when it is produced within the edges of a phrase. Lengthening effects have also been found for words when placed in different syntactic or lexical contexts. Recent evidence suggests that lexico-syntactic information-for example, the global syntactic distributions of words-affects phonetic duration in production, irrespective of other factors. The present study asks whether these lexico-syntactic effects on duration interact with prosodic position within the phrase. Specifically, we ask whether (a) the lexico-syntactic information of a word determines its prosodic position, and (b) whether, beyond any categorical effects on positioning, lexico-syntactic factors affect duration within prosodic positions. We address these questions using the Santa Barbara Corpus of Spoken American English. We operationalize syntactic information as the diversity and the typicality of the syntactic distributions of nouns based on a dependency parse of the British National Corpus. We find that earlier positions in the prosodic phrase generally prefer words with higher syntactic diversity. In addition, diversity and typicality modulate duration more reliably in nonfinal positions. Together, our results point to an early influence of lexico-syntactic considerations on prosodic planning.

2.
Exp Physiol ; 107(12): 1426-1431, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36116111

RESUMO

NEW FINDINGS: What is the central question of this study? Is the plasma concentration of Notch1 extracellular domain altered in response to decreased and increased vascular wall shear stress in the forearm in humans? What is the main finding and its importance? Notch1 extracellular domain is increased with acute increases in antegrade shear rate but does not change with 20 min of decreased shear rate caused by distal forearm occlusion. A novel and integral endothelial mechanosensor in humans that can help explain vascular endothelial adjustments in response to increases in antegrade shear stress was characterized. ABSTRACT: Notch1 has been proposed as a novel endothelial mechanosensor that is central for signalling adjustments in response to changes in vascular wall shear stress. However, there remains no controlled in vivo study in humans. Accordingly, we sought to address the question of whether plasma concentrations of Notch1 extracellular domain (ECD) is altered in response to transient changes in vascular wall shear stress. In 10 young healthy adults (6M/4F), alterations in shear stress were induced by supra-systolic cuff inflation around the wrist. The opposite arm was treated as a time control with no wrist cuff inflation. Plasma was collected from an antecubital vein of both arms at baseline, 20 min of wrist cuff inflation (low shear), as well as 1-2 min (high shear) and 15 min following (recovery) wrist cuff release. The Notch1 ECD was quantified using a commercially available ELISA. Duplex ultrasound was used to confirm alterations in shear stress. In the experimental arm, concentrations of Notch1 ECD remained statistically similar to baseline at all time points except for immediately following cuff release where it was elevated by ∼50% (P = 0.033), coinciding with the condition of high antegrade shear rate. Concentrations of Notch1 ECD remained unchanged in the control arm through all time points. These data indicate that Notch1 is a viable biomarker for quantifying mechanotransduction in response to increased shear stress in humans, and it may underlie the vascular adaptations or mal-adaptations associated with conditions that impact antegrade shear.


Assuntos
Artéria Braquial , Mecanotransdução Celular , Adulto , Humanos , Artéria Braquial/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Estresse Mecânico , Endotélio Vascular/fisiologia , Vasodilatação/fisiologia , Receptor Notch1
3.
Behav Ecol Sociobiol ; 76(9): 122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034316

RESUMO

Abstract: Emerging data in a range of non-human animal species have highlighted a latent ability to combine certain pre-existing calls together into larger structures. Currently, however, the quantification of context-specific call combinations has received less attention. This is problematic because animal calls can co-occur with one another simply through chance alone. One common approach applied in language sciences to identify recurrent word combinations is collocation analysis. Through comparing the co-occurrence of two words with how each word combines with other words within a corpus, collocation analysis can highlight above chance, two-word combinations. Here, we demonstrate how this approach can also be applied to non-human animal signal sequences by implementing it on artificially generated data sets of call combinations. We argue collocation analysis represents a promising tool for identifying non-random, communicatively relevant call combinations and, more generally, signal sequences, in animals. Significance statement: Assessing the propensity for animals to combine calls provides important comparative insights into the complexity of animal vocal systems and the selective pressures such systems have been exposed to. Currently, however, the objective quantification of context-specific call combinations has received less attention. Here we introduce an approach commonly applied in corpus linguistics, namely collocation analysis, and show how this method can be put to use for identifying call combinations more systematically. Through implementing the same objective method, so-called call-ocations, we hope researchers will be able to make more meaningful comparisons regarding animal signal sequencing abilities both within and across systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s00265-022-03224-3.

4.
Plant Cell Rep ; 41(2): 489-492, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854968

RESUMO

KEY MESSAGE: Endogenous U6 promoters increase CRISPR/Cas9 editing efficiency in sorghum and may be useful for gene editing applications in other cereals.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Regiões Promotoras Genéticas , Sorghum/genética , Grão Comestível/genética , Plantas Geneticamente Modificadas
5.
Cognition ; 221: 104986, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34953269

RESUMO

Caretakers tend to repeat themselves when speaking to children, either to clarify their message or to redirect wandering attention. This repetition also appears to support language learning. For example, words that are heard more frequently tend to be produced earlier by young children. However, pure repetition only goes so far; some variation between utterances is necessary to support acquisition of a fully productive grammar. When individual words or morphemes are repeated, but embedded in different lexical and syntactic contexts, the child has more information about how these forms may be used and combined. Corpus analysis has shown that these partial repetitions frequently occur in clusters, which have been coined variation sets. More recent research has introduced algorithms that can extract these variation sets automatically from corpora with the goal of measuring their relative prevalence across ages and languages. Longitudinal analyses have revealed that rates of variation sets tend to decrease as children get older. We extend this research in several ways. First, we consider a maximally diverse sample of languages, both genealogically and geographically, to test the generalizability of developmental trends. Second, we compare multiple levels of repetition, both words and morphemes, to account for typological differences in how information is encoded. Third, we consider several additional measures of development to account for deficiencies in age as a measure of linguistic aptitude. Fourth, we examine whether the levels of repetition found in child-surrounding speech is greater or less than what would have been expected by chance. This analysis produced a new measure, redundancy, which captures how repetitive speech is on average given how repeititive it could have been. Fifth, we compare rates of repetition in child-surrounding and adult-directed speech to test whether variation sets are especially prevalent in child-surrounding speech. We find that (1) some languages show increases in repetition over development, (2) true estimates of variation sets are generally lower than or equal to random baselines, (3) these patterns are largely convergent across developmental indices, and (4) adult-directed speech is reliably less redundant, though in some cases more repetitive, than child-surrounding speech. These results are discussed with respect to features of the corpora, typological properties of the languages, and differential rates of change in repetition and redundancy over children's development.


Assuntos
Idioma , Fala , Adulto , Pré-Escolar , Humanos , Desenvolvimento da Linguagem , Linguística
6.
Philos Trans R Soc Lond B Biol Sci ; 376(1824): 20200198, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33745318

RESUMO

In this paper, we investigate evolutionarily recent changes in the distributions of speech sounds in the world's languages. In particular, we explore the impact of language contact in the past two millennia on today's distributions. Based on three extensive databases of phonological inventories, we analyse the discrepancies between the distribution of speech sounds of ancient and reconstructed languages, on the one hand, and those in present-day languages, on the other. Furthermore, we analyse the degree to which the diffusion of speech sounds via language contact played a role in these discrepancies. We find evidence for substantive differences between ancient and present-day distributions, as well as for the important role of language contact in shaping these distributions over time. Moreover, our findings suggest that the distributions of speech sounds across geographic macro-areas were homogenized to an observable extent in recent millennia. Our findings suggest that what we call the Implicit Uniformitarian Hypothesis, at least with respect to the composition of phonological inventories, cannot be held uncritically. Linguists who would like to draw inferences about human language based on present-day cross-linguistic distributions must consider their theories in light of even short-term language evolution. This article is part of the theme issue 'Reconstructing prehistoric languages'.


Assuntos
Evolução Cultural , Idioma , Percepção da Fala , Fala , Humanos
7.
Behav Brain Sci ; 40: e300, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29342729

RESUMO

We agree with Branigan & Pickering (B&P) that structural priming experiments should supplant grammaticality judgments for testing linguistic representation. However, B&P overlook a vast (corpus-)linguistic literature that converges with - but extends - the experimental findings. B&P conclude that syntax is functionally independent of the lexicon. We argue that a broader approach to priming reveals cracks in the façade of syntactic autonomy.


Assuntos
Linguística
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