1,722,051 research outputs found
An analytical model to relate the vertical root distribution to climate and soil properties
No full textWe propose an analytical model to relate the vertical distribution of plant roots in water controlled ecosystems to the local climatic and pedologic conditions. We find that the shape of the root profile is determined by the distribution of the incoming rainfall pulses, and that the rooting systems are deeper where the soils are coarse-textured and the evaporative demand slightly exceeds precipitation. Citation: Laio, F., P. D'Odorico, and L. Ridolfi (2006), An analytical model to relate the vertical root distribution to climate and soil propertie
Applications of the Functional Renormalization Group: From Statistical Models to Quantum Gravity
Full text linkThe present dissertation is essentially a collection of three investigations, in the context of the functional Renormalization Group. First, we will apply it to scalar models with internal O(N) symmetry, to study their universality classes and how the Mermin-Wagner theorem is seen in the RG framework. Next, we will use it to study Weyl-invariant systems, and in particular to obtain a nonperturbative proof that a quantization procedure respecting Weyl invariance is always possible, regardless of the field content of the theory. Finally, to investigate the corrections to the gravitational beta functions due to the anomalous dimensions of gravitons and ghosts
Cross-Sectional study of coordination between gaze and vocal behavior in prelinguistic and linguistic communication.
No full text
O(N)-Universality Classes and the Mermin-Wagner Theorem
No full textWe study how universality classes of O(N)-symmetric models depend continuously on the dimension d and the number of field components N. We observe, from a renormalization group perspective, how the implications of the Mermin-Wagner-Hohenberg theorem set in as we gradually deform theory space towards d = 2. For a fractal dimension in the range 2 = 1, a finite family of multicritical effective potentials of increasing order. Apart from the N = 1 case, these disappear in d = 2 consistently with the Mermin-Wagner-Hohenberg theorem. Finally, we study O(N = 0)-universality classes and find an infinite family of these in two dimensions. DOI: 10.1103/PhysRevLett.110.14160
Nouns and verbs in the vocabulary acquisition of Italian children
No full textThe vocabulary development of 24 Italian children aged between 1;4 and 1;6 at the beginning of the study was longitudinally monitored on a monthly basis using the Italian version of the MacArthur Communicative Development Inventory drawn up by their mothers. This study analyzes data from children for whom two sampling stages were available; the first corresponding to a vocabulary size as close as possible to 200 words (mean 217, range 167-281), the second to a vocabulary size ranging from 400 to 650 words (mean 518, range 416-648). The children's vocabulary composition was analyzed by calculating, for each sampling stage, the percentage of common nouns, verbs and closed-class words. The increase in percentage points of the various lexical items between the first and second sampling stages was also analyzed. Data confirmed the predominance of nouns over verbs and closed-class words at both sampling stages, while verbs and closed-class words showed a higher percentage increase than nouns. The results provide evidence that children who reached the first sampling point at an earlier age had a higher percentage of nouns than children who reached the same stage at an older age. However, in the passage from the first to the second sampling point no relationship emerged between a style of acquisition based on the acquisition of nouns and an increase in the rate of vocabulary growth
The transition into ambient language: A longitudinal study of babbling and first word production of Italian children
No full textThe present study investigates the appearance of certain phonetic, phonological, and prosodic aspects of Italian in the early language of native speakers; a longitudinal analysis of babbling and word production in 11 Italian children ranging in age from 0;10 to 2;0 is reported. It focuses in particular on the syllabic frequency of babbling utterances and the distribution of consonant sounds in relation to their place of articulation in babbling and first words. It analyzes also the role of phonotactic characteristics and accentual patterns of word targets in production correctness and word shape constraints. Results show that the relationships with the frequency characteristics of the Italian lexicon become increasingly evident in language production from age 0;11 on. The data also provide substantiation for the role of phonotactic characteristics and accentual patterns in influencing correct word production. Finally, a continuity between babbling and words emerged from an analysis of individual differences. The discussion focuses on the role of ambient characteristics of language versus universal articulatory constraints in early phonological development
- …
