Tail risk connectedness between US industries

We use the Least Absolute Shrinkage and Selection Operator (LASSO) quantile regression technique to construct and analyse the complete tail risk connectedness network of the whole US industry system. We also investigate the empirical relationship between input–output linkages and the tail risk spillovers among US industries. Our findings identify the tail‐risk drivers, tail‐risk receivers, and tail‐risk distributors among industries and confirm that the actual trade flow between industries is a major driver of their tail risk connectedness

Learning to read and spell english words by Chinese students

This study examined the structural relationships between (a) the latent independent constructs of orthographic and lexical knowledge and phonological sensitivity and (b) the effect of these constructs on the latent construct of literacy manifested by reading aloud and spelling regular and exception English words in 156 Cantonese-speaking Chinese students (M age = 10.8 years) who were learning English as a second language in Hong Kong. Three carefully designed and item-analyzed indicators subserved the construct of orthographic and lexical knowledge, and another three indicators subserved the construct of phonological sensitivity. Our hypothesis of greater contribution of word-specific orthographic and lexical knowledge than phonological sensitivity to learning to read and spell English words in these Chinese children was supported by results from multiple regression, principal component analyses and especially by structural equation modeling. The various goodness-of-fit indexes showed the appropriateness of the indicators in measuring the latent constructs as well as the relationships among these constructs.published_or_final_versio

Altered functional connectivity in persistent developmental stuttering

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Atypical lateralization of phonological working memory in developmental dyslexia

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Neural systems for auditory perception of lexical tones

Previous neuroimaging research on cognitive processing of speech tone has generated dramatically different patterns of findings. Even at the basic perception level, brain mapping studies of lexical tones have yielded inconsistent results. Apart from the data inconsistency problem, experimental materials in past studies of tone perception carried little or minimal lexical semantics, an important dimension that should not be dispensed with because speech tones serve to distinguish lexical meanings. The present study sought to examine the neural correlates of the perception of speech tone using lexically meaningful experimental stimuli. A simple lexical tone perception task was devised in which native Mandarin speakers were asked to judge whether or not the two syllables of an auditorily presented Chinese bisyllabic word had the same tone. We selected bisyllabic words as experimental stimuli because Chinese monosyllables often convey little or very vague meanings due to rampant homophony. We found that the left inferior frontal gyrus, the right middle temporal gyrus and bilateral superior temporal gyri are responsible for basic perception of linguistic pitches. Our interpretation of the data sees the left superior temporal gyrus as engaged in primary acoustic analysis of the auditory stimuli, while the right middle superior temporal gyrus and the left inferior frontal region are involved in both tonal and semantic processing of the language stimuli.postprin

Use of an alternative method to evaluate erythema severity in a clinical trial: difference in vehicle response with evaluation of baseline and postdose photographs for effect of oxymetazoline cream 1·0% for persistent erythema of rosacea in a phase IV study.

BackgroundOnce-daily topical oxymetazoline cream 1·0% significantly reduced persistent facial erythema of rosacea in trials requiring live, static patient assessments.ObjectivesTo evaluate critically the methodology of clinical trials that require live, static patient assessments by determining whether assessment of erythema is different when reference to the baseline photograph is allowed.MethodsIn two identically designed, randomized, phase III trials, adults with persistent facial erythema of rosacea applied oxymetazoline or vehicle once daily. This phase IV study evaluated standardized digital facial photographs from the phase III trials to record ≥ 1-grade Clinician Erythema Assessment (CEA) improvement at 1, 3, 6, 9 and 12 h postdose.ResultsAmong 835 patients (oxymetazoline n = 415, vehicle n = 420), significantly greater proportions of patients treated with oxymetazoline vs. vehicle achieved ≥ 1-grade CEA improvement. For the comparison between phase IV study results and the original phase III analysis, when reference to baseline photographs was allowed while evaluating post-treatment photographs, the results for oxymetazoline were similar to results of the phase III trials (up to 85.7%), but a significantly lower proportion of vehicle recipients achieved ≥ 1-grade CEA improvement (up to 29.7% [phase 4] vs. 52.3% [phase 3]; P<0.001). In the phase IV study, up to 80·2% of patients treated with oxymetazoline achieved at least moderate erythema improvement vs. up to 22·9% of patients treated with vehicle. The association between patients' satisfaction with facial skin redness and percentage of erythema improvement was statistically significant.ConclusionsAssessment of study photographs, with comparison to baseline, confirmed significant erythema reduction with oxymetazoline on the first day of application. Compared with the phase III trial results, significantly fewer vehicle recipients attained ≥ 1-grade CEA improvement, suggesting a mitigated vehicle effect. This methodology may improve the accuracy of clinical trials evaluating erythema severity

Brain connectivity during the processing of nouns and verbs: a dynamic Bayesian network analysis

Dynamic Bayesian network was used to study the connections among the brain regions activated during processing of nouns and verbs. Under simplifying assumptions, we arrived at a dynamic Bayesian network learning algorithm with reduced time complexity, which allowed us to test all possible connectivity models exhaustively and choose the best model based on the Bayesian information criterion (BIC) score. We found a posterior to anterior flow of processing of both nouns and verbs. The left medial frontal gyrus was found to play an important role in the network. For verb processing, strong involvements of motor cortex and cerebellum were found.published_or_final_versio

Reading in two writing systems: Accommodation and assimilation of the brain's reading network

Bilingual reading can require more than knowing two languages. Learners must acquire also the writing conventions of their second language, which can differ in its deep mapping principles (writing system) and its visual configurations (script). We review ERP (event-related potential) and fMRI studies of both Chinese-English bilingualism and Chinese second language learning that bear on the system accommodation hypothesis: the neural networks acquired for one system must be modified to accommodate the demands of a new system. ERP bilingual studies demonstrate temporal indicators of the brain's experience with L1 and L2 and with the frequency of encounters of words in L2. ERP learning studies show that early visual processing differences between L1 and L2 diminish during a second term of study. fMRI studies of learning converge in finding that learners recruit bilateral occipital-temporal and also middle frontal areas when reading Chinese, similar to the pattern of native speakers and different from alphabetic reading. The evidence suggests an asymmetry: alphabetic readers have a neural network that accommodates the demands of Chinese by recruiting neural structures less needed for alphabetic reading. Chinese readers have a neural network that partly assimilates English into the Chinese system, especially in the visual stages of word identification. © Cambridge University Press 2007.published_or_final_versio