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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.

Environmental factors such as diet, gut microbiota, and infections have proven to have a significant role in epigenetic modifications. It is known that epigenetic modifications may cause behavioral and neuronal changes observed in neurodevelopmental disabilities, including fragile X syndrome (FXS) and autism (ASD). Probiotics are live microorganisms that provide health benefits when consumed, and in some cases are shown to decrease the chance of developing neurological disorders. Here, we examined the epigenetic outcomes in offspring mice after feeding of a probiotic organism, Lactobacillus reuteri (L. reuteri), to pregnant mother animals. In this study, we tested a cohort of Western diet-fed descendant mice exhibiting a high frequency of behavioral features and lower FMRP protein expression similar to what is observed in FXS in humans (described in a companion manuscript in this same GENES special topic issue). By investigating 17,735 CpG sites spanning the whole mouse genome, we characterized the epigenetic profile in two cohorts of mice descended from mothers treated and non-treated with L. reuteri to determine the effect of prenatal probiotic exposure on the prevention of FXS-like symptoms. We found several genes involved in different neurological pathways being differentially methylated (p ≤ 0.05) between the cohorts. Among the key functions, synaptogenesis, neurogenesis, synaptic modulation, synaptic transmission, reelin signaling pathway, promotion of specification and maturation of neurons, and long-term potentiation were observed. The results of this study are relevant as they could lead to a better understanding of the pathways involved in these disorders, to novel therapeutics approaches, and to the identification of potential biomarkers for early detection of these conditions.

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.