264 research outputs found
An ERP study of effects of regularity and consistency in delayed naming and lexicality judgment in a logographic writing system
Phonological access is an important component in theories and models of word reading. However, phonological regularity and consistency effects are not clearly separable in alphabetic writing systems. We investigated these effects in Chinese, where the two variables are operationally distinct. In this orthographic system, regularity is defined as the congruence between the pronunciation of a complex character (or phonogram), and that of its phonetic radical, while phonological consistency indexes the proportion of orthographic neighbors that share the same pronunciation as the phonogram. In the current investigation, regularity and consistency were contrasted in an event-related potential (ERP) study using a lexical decision task and a delayed naming task with native Chinese readers. ERP results showed that effects of regularity occurred early after stimulus onset and were long-lasting. Regular characters elicited larger N170, smaller P200, and larger N400 compared to irregular characters. In contrast, significant effects of consistency were only seen at the P200 and consistent characters showed a greater P200 than inconsistent characters. Thus, both the time course and the direction of the effects indicated that regularity and consistency operated under different mechanisms and were distinct constructs. Additionally, both of these phonological effects were only found in the delayed naming task and absent in lexical decision, suggesting that phonological access was non-obligatory for lexical decision. The study demonstrated cross-language variability in how phonological information was accessed from print and how task demands could influence this process.published_or_final_versio
Distinctive effects of regularity and consistency in orthography-phonology mapping in a logographic writing system: an ERP study
Poster Session E - Motor Control, Speech Production, Sensorimotor Integration: no. E23In alphabetic scripts, phonological regularity and consistency of print-to-sound mapping are not clearly separable. In contrast, these variables are operationally distinct in Chinese. About 80% of Chinese characters are phonograms, containing a semantic radical that provides a clue to the meaning of the character and a phonetic radical providing a clue to the pronunciation (e.g. 趾 zi2 ‘toe’ has a semantic radical 足meaning ‘foot’ and a phonetic radical æ¢ zi2). The orthographyphonology mapping in Chinese can be characterized in terms of regularity defined as the congruence between the pronunciation of a phonogram and that of its phonetic radical, and ...postprin
Learning to read a logographic writing system as a second language: an ERP study of L2 Chinese proficient readers
Poster Session E - Language Development, Plasticity, Multilingualism: no. E33For native readers of alphabetic scripts, learning to read a logographic system such as Chinese is challenging. This is not only because Chinese characters look drastically unlike from words in alphabetic scripts, but also because mappings between orthographic and phonological units in the two systems are different. In this study, we investigated two measures of orthography-phonology mapping-- phonological regularity and consistency--in relatively proficient late-acquired second language (L2) readers of Chinese in lexical decision (LD) and delayed naming (DN) tasks. Most Chinese characters are phonograms, which have a phonetic radical that carries phonological ...postprin
Expression of a quantitative character radius incompletus, temperature effects, and localization of a mobile genetic element Dm-412 in Drosophila melanogaster
International audienc
Processing sublexical phonology in L2 Chinese character reading: An ERP study
Poster Session 2: no. ps2p7Compared to alphabetic scripts, the distinct forms of Chinese characters as orthographic units and the fundamental difference in the mappings between orthographic, phonological, and semantic units lead to specific demands in L2 Chinese processing. The current study examined the sensitivity to and time course of two measures of orthography-phonology mapping-- phonological regularity and consistency-- for relatively proficient L2 readers of Chinese. Most Chinese characters are phonograms, which have a phonetic radical that carries phonological information. Regularity in these phonograms is defined by the congruence between the pronunciation of a phonogram and that of its phonetic radical. Consistency is the extent to which the pronunciation of the phonogram is shared by other …postprin
Spin and valley quantum Hall ferromagnetism in graphene
In a graphene Landau level (LL), strong Coulomb interactions and the fourfold
spin/valley degeneracy lead to an approximate SU(4) isospin symmetry. At
partial filling, exchange interactions can spontaneously break this symmetry,
manifesting as additional integer quantum Hall plateaus outside the normal
sequence. Here we report the observation of a large number of these quantum
Hall isospin ferromagnetic (QHIFM) states, which we classify according to their
real spin structure using temperature-dependent tilted field magnetotransport.
The large measured activation gaps confirm the Coulomb origin of the broken
symmetry states, but the order is strongly dependent on LL index. In the high
energy LLs, the Zeeman effect is the dominant aligning field, leading to real
spin ferromagnets with Skyrmionic excitations at half filling, whereas in the
`relativistic' zero energy LL, lattice scale anisotropies drive the system to a
spin unpolarized state, likely a charge- or spin-density wave.Comment: Supplementary information available at http://pico.phys.columbia.ed
Epidemiology of harmful use of alcohol in Nigeria: a systematic review and meta-analysis
Background: Nigeria, the most populous country in Africa, has reported relatively high levels of alcohol misuse, yet limited resources to guide effective population-wide response. There is a need to integrate existing empirical information in order to increase the power and precision of estimating epidemiological evidence necessary for informing policies and developing prevention programs.
Objectives: We aimed to estimate nationwide and zonal prevalence of harmful use of alcohol in Nigeria to inform public health policy and planning.
Methods: Epidemiologic reports on alcohol use in Nigeria from 1990 through 2018 were systematically searched and abstracted. We employed random-effects meta-analysis and meta-regression model to determine the number of harmful alcohol users.
Results: 35 studies (n = 37,576 Nigerians) were identified. Pooled crude prevalence of harmful use of alcohol was 34.3% (95% CI: 28.6–40.1); twice as high among men (43.9%, 31.1–56.8) compared to women (23.9%, 16.4–31.4). Harmful alcohol use was higher in rural settings (40.1%, 24.2–56.1) compared to urban settings (31.2%, 22.9–39.6). The number of harmful alcohol users aged ≥15 years increased from 24 to 34 million from 1995 to 2015. However, actual age-adjusted prevalence of harmful use of alcohol in Nigeria decreased from 38.5% to 32.6% over the twenty-year period.
Conclusions: While the prevalence of the total population that drinks harmfully appears to be dropping, absolute number of individuals that would be classified as harmful drinkers is increasing. This finding highlights the complexity of identifying and advocating for substance abuse policies in rapidly changing demographic settings common in Africa, Asia, and other developing countries
Artificial graphene as a tunable Dirac material
Artificial honeycomb lattices offer a tunable platform to study massless
Dirac quasiparticles and their topological and correlated phases. Here we
review recent progress in the design and fabrication of such synthetic
structures focusing on nanopatterning of two-dimensional electron gases in
semiconductors, molecule-by-molecule assembly by scanning probe methods, and
optical trapping of ultracold atoms in crystals of light. We also discuss
photonic crystals with Dirac cone dispersion and topologically protected edge
states. We emphasize how the interplay between single-particle band structure
engineering and cooperative effects leads to spectacular manifestations in
tunneling and optical spectroscopies.Comment: Review article, 14 pages, 5 figures, 112 Reference
Properties of Graphene: A Theoretical Perspective
In this review, we provide an in-depth description of the physics of
monolayer and bilayer graphene from a theorist's perspective. We discuss the
physical properties of graphene in an external magnetic field, reflecting the
chiral nature of the quasiparticles near the Dirac point with a Landau level at
zero energy. We address the unique integer quantum Hall effects, the role of
electron correlations, and the recent observation of the fractional quantum
Hall effect in the monolayer graphene. The quantum Hall effect in bilayer
graphene is fundamentally different from that of a monolayer, reflecting the
unique band structure of this system. The theory of transport in the absence of
an external magnetic field is discussed in detail, along with the role of
disorder studied in various theoretical models. We highlight the differences
and similarities between monolayer and bilayer graphene, and focus on
thermodynamic properties such as the compressibility, the plasmon spectra, the
weak localization correction, quantum Hall effect, and optical properties.
Confinement of electrons in graphene is nontrivial due to Klein tunneling. We
review various theoretical and experimental studies of quantum confined
structures made from graphene. The band structure of graphene nanoribbons and
the role of the sublattice symmetry, edge geometry and the size of the
nanoribbon on the electronic and magnetic properties are very active areas of
research, and a detailed review of these topics is presented. Also, the effects
of substrate interactions, adsorbed atoms, lattice defects and doping on the
band structure of finite-sized graphene systems are discussed. We also include
a brief description of graphane -- gapped material obtained from graphene by
attaching hydrogen atoms to each carbon atom in the lattice.Comment: 189 pages. submitted in Advances in Physic
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