Predicting individual differences in preschoolers' numeracy and geometry knowledge: The role of understanding abstract relations between objects and quantities.

Preschoolers' mathematics knowledge develops early and varies substantially. The current study focused on two ontogenetically early emerging cognitive skills that may be important predictors of later math skills (i.e.

Robot-assisted chirality-tunable acoustic vortex tweezers for contactless, multifunctional, 4-DOF object manipulation.

Robotic manipulation of small objects has shown great potential for engineering, biology, and chemistry research. However, existing robotic platforms have difficulty in achieving contactless, high-resolution, 4-degrees-of-freedom (4-DOF) manipulation of small objects, and noninvasive maneuvering of objects in regions shielded by tissue and bone barriers. Here, we present chirality-tunable acoustic vortex tweezers that can tune acoustic vortex chirality, transmit through biological barriers, trap single micro- to millimeter-sized objects, and control object rotation.

Examining Profiles of U.S. Children's Screen Time and Associations with Academic Skills.

Children's screen time (ST) increased in recent years, but investigations of the content and context (e.g., parental presence, and device type) of ST in predicting early academic skills remains understudied.

Diversity of spatial activities and parents' spatial talk complexity predict preschoolers' gains in spatial skills.

Children's spatial activities and parental spatial talk were measured to examine their associations with variability in preschoolers' spatial skills (N = 113, M = 4 years, 4 months; 51% female; 80% White, 11% Black, and 9% other). Parents who reported more diversity in daily spatial activities and used longer spatial talk utterances during a spatial activity had children with greater gains in spatial skills from ages 4 to 5 (β = .17 and β = .

Unpacking the Home Numeracy Environment: Examining Dimensions of Number Activities in Early Childhood.

A growing body of research has examined parents' practices to support their young children's number learning at home, i.e., the home numeracy environment.

Exploring the role of "in the moment" and global caregiver and child factors in caregiver questioning during shared book viewing.

Questions of high (vs. low) cognitive demand (CD), which encourage children to engage in abstract or critical thinking (e.g.

Toddler home math environment: Triangulating multi-method assessments in a U.S. Sample.

Introduction: Current research has documented the home math environment (HME) of preschoolers and kindergarteners. Very few studies, however, have explored the number and spatial activities in which parents engage with children during their toddler years.

Methods: This study examined the HME of 157 toddlers using several methodologies, including surveys, time diaries, and observations of math talk.

Time spent playing predicts early reading and math skills through associations with self-regulation.

Children's play time has declined in recent decades, which could negatively impact early self-regulation-a vital component of school readiness. To date, studies have not fully explored how the time spent playing relates to children's self-regulatory skills, and in turn, their early reading and math competencies. Using data from time diaries and direct assessments of self-regulation, prereading, and math skills, this study examined how minutes spent playing at home predict these skills in a sample of 128 children followed from age four to five.

Self-regulation in toddlers and the emergence of pre-academic disparities.

A growing body of research has examined how children's self-regulation during early and middle childhood mediates SES disparities in academic achievement. Evidence suggests that these self-regulation skills begin developing even earlier, during the toddler years, but more work is needed examining how different measures of self-regulation relate to key constructs such as socioeconomic status (SES) and toddlers' pre-academic skills. In this online study, we examine multiple approaches to measuring self-regulation using confirmatory factor analyses and assess the extent to which self-regulatory skills help explain SES differences in early math and language skills among a sample of 158 two- and three-year-old children.

Associations among socioeconomic status and preschool-aged children's, number skills, and spatial skills: The role of executive function.

Extensive literature has documented socioeconomic status (SES) disparities in young children's standardized math achievement, which primarily reflect differences in basic number and arithmetic skills. In addition, growing evidence indicates that direct assessments of executive function (EF) both predict standardized math achievement and mediate SES differences in standardized math tests. However, early spatial skills and children's approximate number system (ANS) acuity, critical components of later math competence, have been largely absent in this past research.

Acoustofluidic black holes for multifunctional in-droplet particle manipulation.

Acoustic black holes offer superior capabilities for slowing down and trapping acoustic waves for various applications such as metastructures, energy harvesting, and vibration and noise control. However, no studies have considered the linear and nonlinear effects of acoustic black holes on micro/nanoparticles in fluids. This study presents acoustofluidic black holes (AFBHs) that leverage controlled interactions between AFBH-trapped acoustic wave energy and particles in droplets to enable versatile particle manipulation functionalities, such as translation, concentration, and patterning of particles.

Harmonic acoustics for dynamic and selective particle manipulation.

Precise and selective manipulation of colloids and biological cells has long been motivated by applications in materials science, physics and the life sciences. Here we introduce our harmonic acoustics for a non-contact, dynamic, selective (HANDS) particle manipulation platform, which enables the reversible assembly of colloidal crystals or cells via the modulation of acoustic trapping positions with subwavelength resolution. We compose Fourier-synthesized harmonic waves to create soft acoustic lattices and colloidal crystals without using surface treatment or modifying their material properties.

Examining Relations Between Parental Feedback Types and Preschool-Aged Children's Academic Skills.

Prior research has shown associations between parent and teacher feedback and school-aged children's academic outcomes. Specifically, studies have demonstrated that positive feedback (i.e.

Biomimetic apposition compound eye fabricated using microfluidic-assisted 3D printing.

After half a billion years of evolution, arthropods have developed sophisticated compound eyes with extraordinary visual capabilities that have inspired the development of artificial compound eyes. However, the limited 2D nature of most traditional fabrication techniques makes it challenging to directly replicate these natural systems. Here, we present a biomimetic apposition compound eye fabricated using a microfluidic-assisted 3D-printing technique.

Measuring Emerging Number Knowledge in Toddlers.

Recent evidence suggests that infants and toddlers may recognize counting as numerically relevant long before they are able to count or understand the cardinal meaning of number words. The Give-N task, which asks children to produce sets of objects in different quantities, is commonly used to test children's cardinal number knowledge and understanding of exact number words but does not capture children's preliminary understanding of number words and is difficult to administer remotely. Here, we asked whether toddlers correctly map number words to the referred quantities in a two-alternative forced choice Point-to-X task (e.

What's in a question? Parents' question use in dyadic interactions and the relation to preschool-aged children's math abilities.

The cognitive complexity of adults' questions, particularly during shared book reading, supports children's developing language skills. Questions can be described as having low cognitive demand (CD; e.g.

Fabrication of tunable, high-molecular-weight polymeric nanoparticles ultrafast acoustofluidic micromixing.

High-molecular-weight polymeric nanoparticles are critical to increasing the loading efficacy and tuning the release profile of targeted molecules for medical diagnosis, imaging, and therapeutics. Although a number of microfluidic approaches have attained reproducible nanoparticle synthesis, it is still challenging to fabricate nanoparticles from high-molecular-weight polymers in a size and structure-controlled manner. In this work, an acoustofluidic platform is developed to synthesize size-tunable, high-molecular-weight (>45 kDa) poly(lactic-co-glycolic acid)-b-poly(ethylene glycol) (PLGA-PEG) nanoparticles without polymer aggregation by exploiting the characteristics of complete and ultrafast mixing.

Triangulating multi-method assessments of parental support for early math skills.

Past research has examined parental support for math during early childhood using parent-report surveys and observational measures of math talk. However, since most studies only present findings from one of these methods, the construct (parental support for early math) and the method are inextricably linked, and we know little about whether these methods provide similar or unique information about children's exposure to math concepts. This study directly addresses the mono-operation bias operating in past research by collecting and comparing multiple measures of support for number and spatial skills, including math talk during semi-structured observations of parent-child interactions, parent reports on a home math activities questionnaire, and time diaries.

Acoustofluidic rotational tweezing enables high-speed contactless morphological phenotyping of zebrafish larvae.

Modern biomedical research and preclinical pharmaceutical development rely heavily on the phenotyping of small vertebrate models for various diseases prior to human testing. In this article, we demonstrate an acoustofluidic rotational tweezing platform that enables contactless, high-speed, 3D multispectral imaging and digital reconstruction of zebrafish larvae for quantitative phenotypic analysis. The acoustic-induced polarized vortex streaming achieves contactless and rapid (~1 s/rotation) rotation of zebrafish larvae.

Acoustofluidics-Assisted Fluorescence-SERS Bimodal Biosensors.

Acoustofluidics, the fusion of acoustics and microfluidic techniques, has recently seen increased research attention across multiple disciplines due in part to its capabilities in contactless, biocompatible, and precise manipulation of micro-/nano-objects. Herein, a bimodal signal amplification platform which relies on acoustofluidics-induced enrichment of nanoparticles is introduced. The dual-function biosensor can perform sensitive immunofluorescent or surface-enhanced Raman spectroscopy (SERS) detection.

Deterministic droplet coding acoustofluidics.

Droplet microfluidics has become an indispensable tool for biomedical research and lab-on-a-chip applications owing to its unprecedented throughput, precision, and cost-effectiveness. Although droplets can be generated and screened in a high-throughput manner, the inability to label the inordinate amounts of droplets hinders identifying the individual droplets after generation. Herein, we demonstrate an acoustofluidic platform that enables on-demand, real-time dispensing, and deterministic coding of droplets based on their volumes.

Erratum: Acoustofluidic Synthesis of Particulate Nanomaterials.

[This corrects the article DOI: 10.1002/advs.201900913.

Generating multifunctional acoustic tweezers in Petri dishes for contactless, precise manipulation of bioparticles.

Acoustic tweezers are a promising technology for the biocompatible, precise manipulation of delicate bioparticles ranging from nanometer-sized exosomes to millimeter-sized zebrafish larva. However, their widespread usage is hindered by their low compatibility with the workflows in biological laboratories. Here, we present multifunctional acoustic tweezers that can manipulate bioparticles in a disposable Petri dish.