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In recent years, black phosphorus, a new two-dimensional nanomaterial, has been widely used in sensors and analytical instrumentation due to its tunable band gap, high electron mobility and large specific surface area. This article introduces the structure and properties of black phosphorus and its preparation methods, and reviews recent progress in the application of electrochemical sensors based on black phosphorus for the detection of nutrients and harmful substances in foods, harmful substances in food packaging materials. Finally, we summarize the problems in the application of black phosphorus-based electrochemical sensors and provides some suggestions to solve these problems.

Enhanced pitch perception has been identified in autistic individuals, but it remains understudied whether such enhancement can be observed in the lexical tone perception of language-delayed autistic children. This study examined the categorical perception of Mandarin lexical tones in 23 language-delayed autistic children and two groups of non-autistic children, with one matched on chronological age (n = 23) and the other on developmental age in language ability (n = 23). The participants were required to identify and discriminate lexical tones. A wider identification boundary width and a lower between-category discrimination accuracy were found in autistic children than their chronological-age-matched non-autistic peers, but the autistic group exhibited seemingly comparable performance to the group of developmental-age-matched non-autistic children. While both non-autistic groups displayed a typical categorical perception pattern with enhanced sensitivity to between-category tone pairs relative to within-category ones, such a categorical perception pattern was not observed in the autistic group. These findings suggest among language-delayed autistic children with a developmental age around 4, categorical perception is still developing. Finally, we found categorical perception performance correlated with language ability, indicating autistic children's language disability might be predictive of their poor categorical perception of speech sounds.

Abstract Carbon fibre-reinforced polymer (CFRP) plates can efficiently repair or enhance the mechanical properties of the square hollow section. However, the loading end of such a CFRP-strengthened member is prone to local bearing failure under compressive load. Given this limitation, an innovative CFRP-plate-strengthened square hollow section composite member (CFRP-SHSCM) was raised, and the thick-walled section was welded on both ends of the thin-walled steel column. The mechanical properties of CFRP-SHSCMs were investigated through parameter finite element (FE) analysis, focusing on the influence of the amount of CFRP layers (n c ), the slenderness ratio (λ), the initial geometric imperfections (v 0 ), the CFRP layouts (2S and 4S) and the length of the exposed steel column (L e ). The load–displacement curves, the bearing force, and typical failure modes were also acquired. Results indicated that with increasing n c and v 0 , and decreasing λ, the conventional CFRP-SHSCMs were prone to local bearing failure with poor ductility, leading to the insufficient use of the CFRP plate, in contrast, the improved CFRP-SHSCMs primarily underwent overall buckling failure and exhibited better bearing force and ductility. Finally, the modified Perry-Robertson formula was put forward to predict the ultimate load of the CFRP-SHSCMs. The coefficients of variation between the FE simulation and the theoretical results were 0.00436 and 0.0292, respectively.

This study reports on a self-paced reading experiment exploring whether the figurativeness of collocations affects L2 processing of collocations. The participants were 40 English native speakers and 44 Chinese-speaking English foreign language learners (including doctoral, postgraduate, and undergraduate students). To ensure that the effect emerged from the figurativeness of collocations rather than other item-related confounds, this study added a literal-literal comparison (e.g., choose a career vs. choose a house) as a control to the experimental figurative-literal comparison (e.g., build a career vs. build a house). Results showed that L2 speakers processed figurative collocations more slowly than literal collocation controls but native speakers did not. Importantly, this processing cost for figurative collocations in L2 speakers varied by L2 proficiency but not phrase familiarity. We discuss the results in terms of the dual-route model of formulaic and novel language processing and also incorporate them into the literal salience model of bilingual figurative processing.

Background: Teaching Mandarin as a second language (L2) has become an important profession and an important research area. The acquisition of unaspirated and aspirated consonants in Mandarin has been reported to be rather challenging for L2 learners. Objectives: In the current study, a 3-D airflow model was integrated into the virtual talking head for audiovisual pronunciation training in these Mandarin consonants. Methods: Using the eye-tracking technique, Experiment 1 investigated L2 learners' general acceptance and gauged attention distribution online while learning with the system. To further compare training efficacy, learning outcomes were evaluated by randomly dividing Japanese learners of Mandarin into different training groups using the 3-D tutor with and without an airflow model, respectively, in Experiment 2. Results and Conclusions: Eye-tracking results showed that the talking head was well accepted, and was successful in directing L2 learners' attention to the visual modality of the airflow model marking the contrast in aspiration. Furthermore, the additional visual cue of the airflow model helped enhance their production of the aspirated Mandarin stops. Moreover, this computer-assisted training approach was shown to be robust as the advantage of training with an airflow model can be generalized to novel syllables with a change of tones or rimes.

Although children develop categorical speech perception at a very young age, the maturation process remains unclear. A cross-sectional study in Mandarin-speaking 4-, 6-, and 10-year-old children, 14-year-old adolescents, and adults (n = 104, 56 males, all Asians from mainland China) was conducted to investigate the development of categorical perception of four Mandarin phonemic contrasts: lexical tone contrast Tone 1-2, vowel contrast /u/-/i/, consonant aspiration contrast /p/-/p[superscript h]/, and consonant formant transition contrast /p/-/t/. The results indicated that different types of phonemic contrasts, and even the identification and discrimination of the same phonemic contrast, matured asynchronously. The observation that tone and vowel perception are achieved earlier than consonant perception supports the phonological saliency hypothesis.

Background: White pitaya, a popular tropical fruit, is known for its high nutritional value. It is commercially cultivated worldwide for its potential use in the food and pharmaceutical industries. This study aims to assess the nutritional and phytochemical contents and biological potential of the South Chinese White Pitaya (SCWP) peel, flesh, and seed extracts. Methods: Extract fractions with increasing polarity (ethyl acetate

Purpose: Cochlear implants (CIs) provide significant benefits for profoundly deaf children in their language and cognitive development. However, it remains unclear whether Mandarin-speaking young children with early implantation can develop age-equivalent phonological awareness (PA) skill and working memory (WM) capacity as their normal hearing (NH) peers. The aim of this study was to investigate PA and WM in preschool-aged children with or without hearing loss and to examine the relationship between the two basic skills. Method: The data were collected from 16 Mandarin-speaking preschoolers with CIs and 16 age-matched children with NH. All preschool participants were instructed to complete four phonological detection tasks and four digit span tasks. Linear mixed-effects modeling was performed to evaluate PA and WM performances between two groups across different tasks. Results: CI preschoolers showed comparable performances on par with NH controls in phonological detections and visual digit spans. In addition, Pearson correlation analysis revealed a positive relationship between phonological detections and auditory digit spans in preschool-aged children with CIs. Conclusion: With early implantation, the congenitally deaf children were capable of developing age-appropriate PA skill and WM capacity, which have practical implications for aural rehabilitation in this special pediatric population.

Purpose: This study investigated the categorical perception of Mandarin tones and consonant aspiration contrasts in babble noise among adults and adolescents aged 12-14 years, and explored the association between working memory and categorical perception. Method: Twenty-four adults and 20 adolescents with Mandarin as their native language were recruited. Their performances of phonemic identification and discrimination in babble noise and quiet conditions, digit span tasks, and nonword repetition were assessed. Results: Results indicated that, firstly, in the noise condition, both adults and adolescents showed wider boundary widths and lower between-category accuracies when perceiving aspiration of consonants than in the quiet condition, and the categorical boundary of tone perception in adolescents showed a transitional tendency toward Tone 1. Secondly, discrimination of consonant aspiration in adolescents needed to be further developed. Lastly, the accuracy of nonword repetition in adolescents was lower than that in adults, and adults with better auditory verbal working memory had better performance on tone perception. Conclusions: Our results provided evidence that tone perception is acquired easier than consonant aspiration perception, and tone perception is more robust and less susceptible to noise interference. Categorical perception performance relates to the capacity and utilization of auditory verbal working memory in some ways.