Measuring children's sustained selective attention and working memory: validity of new minimally linguistic tasks.

This study introduces visual tasks using nonlinguistic stimuli that measure sustained selective attention (SSA) and working memory (WM), two constructs foundational to learning and associated with developmental disorders in children. Using an argument-based approach to validation, we examine whether each task (a) measures distinct constructs, (b) shows internal consistency, (c) captures a range of performance, and (d) relates to development as indexed by age. Participants included 71 children, ages 4-10, of whom 12 had parental concern for language/learning. The SSA task presented spatial locations within a long and uninteresting task, following the continuous performance task paradigm. The WM task presented paired location sequences of increasing length, incorporating key elements of the n-back and complex span paradigms. Controlling for age, tasks were found to be minimally associated with each other (r = .26), suggesting related but distinct constructs. Internal consistency was high, with split-half reliability of .94 (SSA) and .92 (WM); the stability of these estimates was supported by bootstrapping simulations. Task performance was evenly distributed, with minimal floor or ceiling effects within this age range. Performance was positively related to age (SSA r = .49; WM r = .53). Exploratory correlations with a measure of parental concern were significant for SSA but not WM. The results show that these new tasks can be used to measure children's SSA and WM in a visual domain with minimal linguistic influence. These tasks capture developmental changes in the early school years. Further investigation can examine their utility for classifying children with developmental disorders.

A Narrative Approach to Synthesizing Research on Vietnamese Bilingual and Monolingual Children.

PURPOSE: This review article offers a narrativized synthesis of my research over the past 15+ years with Vietnamese-speaking children based on data collected from individual bilingual and monolingual children in preschool and elementary schools. METHOD: I begin with a positionality narrative to describe who I am in relation to the research conducted. I provide an overview of the research program including tool building and how my research with bilinguals in the United States led me to international collaborations in Vietnam. RESULTS: I present main findings from this body of work in three areas: typical bilingual development, reading performance in Vietnam, and characteristics of developmental language disorder in the Vietnamese language. Implications within each area are discussed in terms of clinical application and future research directions. Practitioners and researchers alike can freely access the Vietnamese assessment tools created and validated to date from our website, https://vietslp.sdsu.edu/. CONCLUSIONS: This research overview aims to offer clinicians and researchers the sociocultural context for understanding the relevance of this body of research. It also serves as an invitation for new generations of scholars, particularly scholars of color, to see their own unique positionings and perspectives as valuable and necessary for scientific innovation and progress. PRESENTATION VIDEO: https://doi.org/10.23641/asha.23929491.

What predicts individual response to language treatment in bilingual children with developmental language disorder?

Purpose: For bilingual children with developmental language disorder (DLD), language treatment response is the degree to which an individual child progresses in both of their languages. Understanding what predicts language treatment response for an individual child can help clinicians plan treatment more effectively. Methods: This study is a retrospective analysis of data from Ebert et al. (2014). Participants included 32 school-age Spanish-English bilingual children with DLD who completed an intensive language treatment program. Gains in Spanish and English were measured using raw test scores in each language. Predictors of language gains include language, cognitive, and demographic variables. To examine which predictors were significant, we calculated partial correlations between the potential predictors and the posttreatment language test scores, controlling for the effects of pretreatment test scores. Results: In Spanish, several predictors correlated with the outcome measures. After controlling for pretreatment scores, English grammaticality, female sex, processing speed, age, and fluid reasoning were related to Spanish posttreatment scores. In English, correlations with individual predictors were minimal. After controlling for pretreatment scores, only one variable was associated with one English posttreatment score: English grammaticality. Conclusions: The original study reported limited gains in Spanish compared to robust gains in English (Ebert et al., 2014). Treatment response in Spanish is more variable given the lack of environmental support for Spanish in the US. As a result, individual factors (including nonverbal cognition, pretreatment language levels, and demographic variables) influence treatment gains in Spanish. In contrast, strong environmental support for English supports a more consistent treatment response, with a smaller role for individual factors.

Exploring the potential of ZnO-Ag@AgBr/SBA-15 Z-scheme heterostructure for efficient wastewater treatment: synthesis, characterization, and real-world applications.

This study reports on the synthesis and characterization of ZnO-Ag@AgBr/SBA-15 composites using natural halloysite clay from Yenbai Province, Vietnam, as a silica aluminum source. The synthesized materials demonstrated visible light absorption with a band gap energy range of 2.63-2.98 eV. The dual Z-scheme ZnO-Ag@AgBr/SBA-15 heterojunction exhibited superior catalytic performance compared to ZnO/SBA-15 and Ag@AgBr/SBA-15, owing to its improved electron transfer and reduced electron and hole recombination rate. In particular, the photocatalytic efficiency of ZnO-Ag@AgBr/SBA-15 was evaluated for the removal of harmful phenol red from wastewater under visible light irradiation. The photocatalytic process was optimized by varying the phenol red concentration, pH, and catalyst dosage, and showed that 98.8% of phenol red in 100 mL wastewater (pH = 5.5) can be removed using 40 mg of 20%ZnO-Ag@AgBr/SBA-15 within 120 min. Furthermore, the degradation pathway of phenol red was predicted using liquid chromatographic-mass spectrometry (LC-MS). Finally, the photocatalytic process was successfully tested using water samples collected from the four main domestic waste sources in Hanoi, including the To Lich River, the Hong River, the Hoan Kiem Lake, and the West Lake, demonstrating the high potential of the ZnO-Ag@AgBr/SBA-15 photocatalyst for phenol red degradation in real-world wastewater treatment applications.

Remote First-Language Assessment: Feasibility Study With Vietnamese Bilingual Children and Their Caregivers.

PURPOSE: There is a shortage of bilingual speech-language pathologists (SLPs) in the United States. For Vietnamese, less than 1% of SLPs speak the language compared with a Vietnamese American population of > 2.1 million. This study examines the feasibility and social validity of remote child language assessment with the help of a caregiver to address the need for first language assessments among Vietnamese-speaking children. METHOD: Twenty-one dyads of caregivers and typically developing children (aged 3-6 years) completed two assessment sessions in their first language, Vietnamese, using Zoom videoconferencing. Sessions were counterbalanced between two conditions in which either the clinician or the caregiver was the task administrator. Children's language samples were elicited using narrative tasks. Social validity was also assessed through caregiver and child questionnaires at the end of each session. RESULTS: There were no significant differences between conditions on language sample measures nor the measures of social validity. Both caregivers and their children felt positively about the sessions. The caregivers' feelings were related to their perception of children's feelings about the sessions. Children's feelings were related to their Vietnamese language proficiency, caregiver-reported language ability, and whether they were born outside of the United States. CONCLUSIONS: Findings build the evidence base for telepractice as an effective and socially valid service delivery model for bilingual children in the United States. This study supports the potential for caregivers as task administrators in a telepractice setting, making assessment in a child's first language more feasible and accessible. Future investigation is needed to extend results to bilingual populations with disorders.

Reading Attitudes in Vietnam: Initial Study of the Early School Years.

Whereas cognitive and linguistic factors for learning to read have been extensively studied, less is known about affective factors including children's attitudes toward reading. Studies primarily from English-speaking and Western countries show gradual declines in reading attitudes in elementary school (McKenna et al., 1995) and a positive association between reading attitudes and achievement (Petscher, 2010). Children from Asian and African countries are underrepresented in this literature; whether these patterns can be generalized across cultures needs further investigation. This longitudinal study examined the reading attitudes of 84 children in Vietnam from grades 1 to 2 and their relations to reading performance, as measured by translated and adapted versions of the Elementary Reading Attitude Survey and Early Grade Reading Assessment, respectively. This sample from Vietnam showed a small decline in reading attitudes over time, particularly in attitudes toward academic reading. However, children on average reported feeling happy about reading in both grades. Correlations revealed different patterns of association between reading attitudes and performance based on the reading measure employed, grade level, and type of reading in question (academic versus recreational). In grade 2, reading attitudes explained unique variance in reading comprehension even after text fluency and mother's education were considered. We present a margins plot to visualize the role of reading attitudes on reading comprehension. We discuss educational implications and future directions.

Is There a Cognate Effect in Bilingual Children With Developmental Language Disorder?

PURPOSE: Cognates, words in two languages that share form and meaning, can be used to support vocabulary development in bilingual children. Typically developing bilinguals have shown better performance on cognates versus noncognates. Of key interest is whether bilinguals with developmental language disorder (DLD) also show a cognate effect and, if so, which factors are related to their cognate performance. METHOD: Thirty-five Spanish-English bilingual children (5-11 years old) with DLD completed the Expressive and Receptive One-Word Picture Vocabulary Tests, third edition, in English (EOW, ROW) to measure cognate performance. Test items were divided by difficulty level (easy, medium, and hard) and classified as cognates or noncognates using the Cross-Linguistic Overlap Scale for Phonology. RESULTS: On average, children showed clear and robust cognate effects on EOW across difficulty levels with medium-to-large effect sizes. Results on the ROW showed minimal effects that varied by difficulty. Individually, 80% of participants (28 of 35) demonstrated a cognate effect in EOW, whereas only 31% (11 of 35) showed an effect in ROW. A cognate effect in ROW was positively correlated with age and English proficiency, whereas no factors correlated with the EOW cognate effect. CONCLUSIONS: Bilingual children with DLD show higher performance on cognates than noncognates, at least in expressive vocabulary. Participants who did show a receptive cognate effect tended to be older and have higher English proficiency. Further investigation is needed to identify factors underlying cognate performance in order to tailor intervention strategies that promote bilingual vocabulary development.

Capitalizing on cross-language similarities in intervention with bilingual children.

PURPOSE: This study examined the effects of a vocabulary intervention for bilingual children that was conducted in children's first language, Spanish, and included explicit instruction on cognates. We measured effects in terms of change from pre- to post-intervention in Spanish as well as associations with the non-target language, English. METHOD: Participants were 12 Spanish-English bilingual children, aged 6-8 years, with and without Developmental Language Disorder. Children completed the intervention in pairs (one child with DLD and a typically developing peer) for 70-minute sessions, 3 days a week, for four weeks. Intervention targeted 32 words (16 cognates, 16 non-cognates) using four storybooks (8 words/book) and interactive activities that highlighted similarities across languages. Pre- and post-intervention measures in Spanish and English included tasks of word definition and cognate facilitation. RESULTS: As a group, children showed improvement in definition quality and cognate naming in Spanish. There was a positive correlation between definition quality and cognate naming for the typically developing children, but not for the children with DLD. All children showed positive cross-language correlations on post-intervention measures. CONCLUSIONS: Bilingual children, with and without DLD, have the capacity to improve in their awareness and use of cognates. Explicit teaching of cognates can be an effective tool for building vocabulary skills. Children with DLD may need additional time and support to apply their knowledge of cognates to vocabulary learning.

Identifying Developmental Language Disorder in Vietnamese Children.

Purpose Developmental language disorder (DLD), defined by low language performance despite otherwise normal development, can negatively impact children's social and academic outcomes. This study is the 1st to examine DLD in Vietnamese. To lay the foundation, we identified cases of DLD in Vietnam and explored language-specific characteristics of the disorder. Method Teacher ratings of 1,250 kindergarteners living in Hanoi, Vietnam, were used to recruit children with and without risk for DLD. One hundred four children completed direct measures of vocabulary and language sampling, and their parents completed in-depth surveys. We examined convergence and divergence across tasks to identify measures that could serve as reliable indicators of risk. Then, we compared performance on direct language measures across ability levels. Results There were positive associations between teacher and parent report and between report and direct language measures. Three groups were identified based on convergence across measures: DLD, some risk for DLD, and no risk. The DLD group performed lowest on measures of receptive and expressive vocabulary, mean length of utterance, and grammaticality. Although children with DLD exhibited a greater number of errors, the types of errors found were similar across DLD and No Risk groups. Conclusions Similar to rates found globally, 7% of the kindergarten population in Vietnam exhibited risk for DLD. Results highlight the importance of parent and teacher report and the value of multiple measures to identify DLD. We discuss potential clinical markers for DLD in the Vietnamese language and outline future directions.

Cross-language nonword repetition by bilingual and monolingual children.

PURPOSE: Identifying children with primary or specific language impairment (LI) in languages other than English continues to present a diagnostic challenge. This study examined the utility of English and Spanish nonword repetition (NWR) to identify children known to have LI. METHOD: Participants were 4 groups of school-age children (N = 187). There were 2 typically developing groups: proficient Spanish-English sequential bilinguals and monolingual English speakers. There were 2 groups of children with LI, one Spanish-English and the other monolingual English speakers. Children participated in both English and Spanish NWR. RESULTS: Children's NWR performance was significantly correlated across languages. In English NWR, the 2 groups with LI had lower accuracy at the longest syllable length than the 2 typically developing groups. In Spanish NWR, monolingual children with LI had lower repetition accuracy than bilingual children with LI and typical monolingual children, with all 3 groups outperformed by the typical bilingual group. Likelihood ratios indicated adequate diagnostic power only for English NWR in ruling out the typical bilingual children as showing LI. CONCLUSION: The results demonstrate that NWR performance relies on the dual influences of LI and native language experience. However, it remains possible that NWR is useful in a composite marker for LI.

Mechanical and electrical properties of polycarbonate nanotube buckypaper composite sheets.

The thermogravimetric, mechanical, and electrical properties of composite sheets produced by infiltrating single-wall carbon nanotube films (also known as 'buckypapers') with polycarbonate solution were characterized. The composite sheets showed improved stiffness and toughness, while the electrical conductivity decreased, as compared to a neat buckypaper. In addition, polycarbonate/buckypaper composite sheets showed higher resistance to handling and processing damages. Experimental results suggest the viability of the infiltration process as a means to toughen buckypapers and to fabricate polymer/carbon nanotube composites having high nanotube concentration and controlled nanotube structure.