593 research outputs found

    Beyond the realm of noun and verb: the cognitive lexicon of the young child

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    Most studies of early lexical development are focused on the acquisition of the noun or verb categories. Only studies targeting the very beginning of word production describe the rich pattern of reference and expressive words produced by very young children. Still, during their second year, children’s production in tokens contains as many words that are not nouns and verbs than words that are. The importance of categories such as communicators, adverbs, pointers and adjectives never decreases, neither in English nor in French children between the age of 1;6 to 2;6. A cross-linguistic comparison shows that the same type of words is the most frequent in English and French children, while a comparison with adult production shows that, in neither language, do the words produced by children match exactly the words they hear most frequently. The difference in the syntactic structure of English and French argues strongly for a cognitive origin to this close match of the children’s words. These words other than nouns and verbs are more complex than they appear, because they cover a whole range of reference principles – direct reference, indirect reference, shared reference, generic reference, multiple reference, ambiguity, similarity, repetition, absence of –, as well as a wide range of expressive meanings. This type of words appears and grows throughout the children’s second year and provides the basic stones for further lexicon and syntax development

    Chemical composition of the unexplored volatile fraction of betula glandulosa, a prevalent shrub in Nunavik, Québec

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    The volatile fraction of the leaves of Betula glandulosa Michx. has been investigated for its secondary metabolite composition by GC/MS and GC/FID. The rapid expansion of this shrub species in subarctic landscapes, like the ones found in Nunavik (Northern Québec, Canada), highly impacts ecosystem dynamics. Yet, despite its abundance, few phytochemical investigations have yet been conducted on this species. In this study, we present the first phytochemical investigation of the volatile metabolites of B. glandulosa leaves. Although no essential oil was isolated, volatile compounds were extracted from the hydrosol by steam distillation. The main metabolites observed were linalool (14.6–19.0 %), C6 oxylipins (known as green leaf volatiles, GLV; total of 18.2–40.2 %), eugenol (1.6–8.6 %) and α-terpineol (3.3–4.8 %). Dwarf birch is an important food source for insects and herbivores, so knowledge of its metabolite composition could help understand parts of its functional role in subarctic ecosystems. The composition of the volatile fraction could serve as marker for differentiating B. glandulosa from other dwarf birch species like Betula nana L

    Deciphering mango tree asynchronisms using Markov tree and probabilistic graphical models

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    ISBN 978-951-651-408-9International audienceTree development is often characterised by complex dependencies between daughter growth units (GUs) deriving from a given mother GU, the so-called sister GUs. These dependencies directly affect the reproductive and vegetative phenological patterns that are at the origin of asynchronisms between adjacent GUs, eventually leading to within-canopy patchiness. These phenomena are rather common on tropical fruit-trees. We introduce new parsimonious statistical models to identify such dependencies. The proposed approach is illustrated on mango tree, a tropical species with a particularly complex timing of development. We focus especially on differences on fates and dates of burst between the daughter GUs issued from a same mother GU

    Source X par agrégats : contrôle et optimisation des paramètres gouvernant línteraction laser de puissance - agrégats de gaz rare

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    National audienceLes expériences que nous avons réalisées sur le Laser Ultra Court Accordable du CEA Saclay permettent dóbserver l\'émission de photons X dans la gamme 1-5 keV lors de lírradiation dágrégats de gaz rare (Ar, Kr et Xe comprenant entre 10^3 et 10^6 atomes par agrégat) avec un laser femtoseconde de puissance (Ipic jusqu\'à 10^17 W/cm²). En plus de la distribution des états de charge des ions responsables de l\'émission X, la technique de spectroscopie X que nous utilisons permet de mesurer les taux absolus de photons émis dans 4π par impulsion laser en fonction des paramètres gouvernant línteraction dans des conditions contrôlées. Nous avons déterminé la sensibilité des paramètres physiques régissant la production du rayonnement X pendant línteraction, ce qui permet dáccéder à lóptimisation de cette source. Cet article est plus particulièrement dédié aux résultas relatifs à l\'évolution du taux d\'X avec l\'éclairement laser, dúne part, et avec la durée de límpulsion laser, dáutre part

    Émission X(L) du xénon par interaction laser -agrégats

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    National audienceNous avons étudié le rayonnement X provenant d'ions fortement multichargés (" 24+) présentant des lacunes en couche L produits lors de l'irradiation d'agrégats de xénon par des impulsions lumineuses issues d'un laser femtoseconde de puissance. Les résultats obtenus lors de la toute dernière campagne d'expériences réalisée auprès du serveur LUCA du SPAM/DRECAM au CEA/Saclay mettent en cause certains travaux antérieurs. Des divergences marquées apparaissent tant au niveau de l'interprétation des spectres X que sur la variation du taux d'émission en fonction de l'éclairement et de la longueur d'onde

    Trans regulation in the Ultrabithorax gene of Drosophila: alterations in the promoter enhance transvection

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    PMCID: PMC556824We report a genetic and molecular study of UbxMX6 and Ubx195rx1, two mutations in the Ultrabithorax (Ubx) locus which appear to have a strong effect on the activity of the homologous Ubx gene. These mutations show the characteristic embryonic and adult phenotypes of Ubx null alleles, and also fail to produce any detectable Ubx product. Yet, genetic and phenotypic analyses involving a large number of trans heterozygous combinations of UbxMX6 and Ubx195rx1 with different classes of Ubx mutations, indicate that they hyperactivate the homologous gene. This effect is induced on wildtype or mutant forms of Ubx, provided that the pairing in the bithorax region is normal, i.e. these mutations have a strong positive effect on transvection. We also show that, unlike all the other known cases of transvection in Ubx, this is not zeste-dependent. Southern analyses indicate that UbxMX6 is a 3.4 kb deletion, and Ubx195rx1 is an approximately 11 kb insertion of foreign DNA, both in the promoter region. We speculate that the region altered in the mutations may have a wildtype function to ensure cis-autonomy of the regulation of Ubx transcription.This work was supported by grants from the DGICYT and the FundaciĂłn RamĂłn Areces.Peer reviewe

    Dynamique sub-picoseconde de l'interaction laser de puissance – agrégats de gaz rare : émission intense de rayons X et production d'ions multichargés.

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    National audienceLors de campagnes d'expériences réalisées sur le Laser Ultra Court Accordable du CEA/Saclay, nous avons étudié le rayonnement X, tant qualitativement (spectroscopie et énergie moyenne des photons) que quantitativement (taux absolus et lois d'évolution), émis lors de l'interaction d'un jet effusif d'agrégats de gaz rare (Ar, Kr, Xe comprenant entre 10^4 et 10^6 atomes/agrégat) avec un laser femtoseconde de puissance (éclairement jusqu'à quelques 10^17 W/cm2). Les résultats présentés dans ce manuscrit sont uniquement dédiés aux agrégats d'Ar pour lesquels nous avons observé un rayonnement X issu d'ions fortement multichargés (jusqu'à l'Ar16+) présentant des lacunes en couches K. La technique de spectroscopie X utilisée a permis de déterminer pour la première fois des taux absolus ainsi que les lois d'évolution de l'émission X en fonction de l'ensemble des paramètres gouvernant l'interaction (intensité, polarisation, longueur d'onde et durée du pulse laser aussi bien que taille, densité et numéro atomique des agrégats)

    Replenish and relax: explaining logarithmic annealing in disordered materials

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    Fatigue and aging of materials are, in large part, determined by the evolution of the atomic-scale structure in response to strains and perturbations. This coupling between microscopic structure and long time scales remains one of the main challenges in materials study. Focusing on a model system, ion-damaged crystalline silicon, we combine nanocalorimetric experiments with an off-lattice kinetic Monte Carlo simulation to identify the atomistic mechanisms responsible for the structural relaxation over long time scales. We relate the logarithmic relaxation, observed in a number of systems, with heat-release measurements. The microscopic mechanism associated with logarithmic relaxation can be described as a two-step replenish and relax process. As the system relaxes, it reaches deeper energy states with logarithmically growing barriers that need to be unlocked to replenish the heat-releasing events leading to lower energy configurations

    Gęste mapowanie regionu VNTR genu insuliny w zespole policystycznych jajników w populacji kobiet z Europy Środkowej

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    Introduction: Insulin gene VNTR was associated with polycystic ovary syndrome (PCOS) in some studies but not in others. This couldb be due to the heterogeneity of the definition of PCOS and/or the use of inappropriate gene mapping strategies.Material and methods: In this investigation, the association of VNTR with PCOS was explored in a population of women from Central Europe (377 cases and 105 controls) in whom PCOS was diagnosed according to Rotterdam criteria. Seven SNPs: rs3842756 (G/A), rs3842755 (G/T), rs3842754 (C/T), rs3842753 (A/C), rs3842752 (C/T), rs3842748 (G/C), and rs689 (T/A) were genotyped in a portion of the population (160 cases and 95 controls) by sequencing or by SSO-PCR. Analysis of linkage disequilibrium (LD) pattern allowed selecting three tagSNPs (rs3842754, rs3842748, and rs689), which were genotyped in the rest of the population by KASPar.Results: Six haplotypes were reconstructed, among which three (h1, h2 and h6) were more frequent. Statistical analysis allowed observation of the association of the SNP rs3842748, through its GC genotype, with obesity in PCOS (P = 0.049; OR CI95% 1,59 [1.00–2.51]) and in classical PCOS (YPCOS) (P = 0.010), as well as the correlation of the SNP rs689 and the pair of haplotypes h1/h1 with higher levels of testosteronaemia in the PCOS group, although this was at the limit of significance (P = 0.054)Conclusion: These results are in accordance with some studies in literature and highlight the role of insulin gene VNTR in complex metabolic disorders. (Endokrynol Pol 2015; 66 (3): 198–206)Wstęp: W niektórych badaniach, zmienna liczba powtórzeń tandemowych (VNTR) genu insuliny była związana z zespołem policystycznych jajników (PCOS), lecz w innych taki związek nie występował. Mogło tak być z powodu heterogeniczności definicji PCOS i/lub stosowania nieprawidłowych strategii mapowania genów.Materiał i metody: W niniejszym badaniu, związek VNTR z PCOS zbadano w populacji kobiet pochodzących z Europy Środkowej (377 przypadków chorobowych oraz 105 osób kontrolnych), u których zdiagnozowano PCOS według kryteriów rotterdamskich. Siedem polimorfizmów pojedynczego nukleotydu (SNP): rs3842756 (G/A), rs3842755 (G/T), rs3842754 (C/T), rs3842753 (A/C), rs3842752 (C/T), rs3842748 (G/C), oraz rs689 (T/A) wytypowano w części populacji (160 przypadków chorobowych i 95 osób kontrolnych) poprzez sekwencjonowanie lub SSO-PCR. Analiza wzoru niezrównoważenia sprzężeń (LD) pozwoliła na selekcję trzech SNP znacznikowych (tagSNP) (rs3842754, rs3842748 i rs689), które wyselekcjonowano w pozostałej części populacji metodą KASPar.Wyniki: Sześć haplotypów odtworzono, z których 3 (h1, h2 i h6) występowały częściej. Analiza statystyczna pozwoliła na obserwację związku SNP rs3842748, poprzez genotyp GC, z otyłością w PCOS (P = 0,049; OR CI 95% 1,59 [1,00–2,51]) i klasycznym PCOS (YPCOS) (P = 0,010), jak również korelacji SNP rs689 i pary haplotypów h1/h1 z wyższym stężeniem testosteronemii w grupie PCOS, chociaż wynik ten znajdował się na granicy istotności (P = 0,054).Wnioski: Powyższe wyniki są zgodne z niektórymi badaniami w piśmiennictwie i podkreślają role VNTR genu insuliny w złożonych zaburzeniach metabolicznych. (Endokrynol Pol 2015; 66 (3): 198–206

    Early-onset catatonia associated with SHANK3 mutations: looking at the autism spectrum through the prism of psychomotor phenomena

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    BackgroundIndividuals with Phelan-McDermid syndrome (PMS) present with a wide range of diagnoses: autism spectrum disorder, intellectual disability, or schizophrenia. Differences in the genetic background could explain these different neurodevelopmental trajectories. However, a more parsimonious hypothesis is to consider that they may be the same phenotypic entity. Catatonic disturbances occasionally reported from adolescence onwards in PMS prompts exploration of the hypothesis that this clinical entity may be an early-onset form of catatonia. The largest cohort of children with childhood catatonia was studied by the Wernicke-Kleist-Leonhard school (WKL school), which regards catatonia as a collection of qualitative abnormalities of psychomotricity that predominantly affecting involuntary motricity (reactive and expressive). The aim of this study was to investigate the presence of psychomotor signs in three young adults carrying a mutation or intragenic deletion of the SHANK3 gene through the prism of the WKL school conception of catatonia.MethodsThis study was designed as an exploratory case study. Current and childhood psychomotor phenomena were investigated through semi-structured interviews with the parents, direct interaction with the participants, and the study of documents reporting observations of the participants at school or by other healthcare professionals.ResultsThe findings show catatonic manifestations from childhood that evolved into a chronic form, with possible phases of sub-acute exacerbations starting from adolescence.ConclusionThe presence of catatonic symptoms from childhood associated with autistic traits leads us to consider that this singular entity fundamentally related to SHANK3 mutations could be a form of early-onset catatonia. Further case studies are needed to confirm our observations
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