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Data-driven decision making (DDDM) helps educators identify children not responding to intervention, individualize instruction, and monitor response to intervention in multitiered systems of support (MTSS). More prevalent in K-12 special education, MTSS practices are emerging in early childhood. In previous reports, we described the Making Online Decisions (MOD) web application to guide DDDM for educators serving families with infants and toddlers in Early Head Start home-visiting programs. Findings from randomized control trials indicated that children at risk for language delay achieved significantly larger growth on the Early Communication Indicator formative language measure if their home visitors used the MOD to guide DDDM, compared to children whose home visitors were self-guided in their DDDM. Here, we describe findings from a randomized control trial indicating that these superior MOD effects extend to children's language growth on standardized, norm-referenced language outcomes administered by assessors who were blind to condition and that parents' use of language promotion strategies at home mediated these effects. Implications and limitations are discussed.

Research has shown that the context of practice tasks can have a significant impact on learning, with long-term retention and transfer improving when tasks of different types are mixed by interleaving (abcabcabc) compared with grouping together in blocks (aaabbbccc). This study examines the influence of context via interleaving from a psychometric perspective, using educational assessments designed for early childhood. An alphabet knowledge measure consisting of four types of tasks (finding, orienting, selecting, and naming letters) was administered in two forms, one with items blocked by task, and the other with items interleaved and rotating from one task to the next by item. The interleaving of tasks, and thereby the varying of item context, had a negligible impact on mean performance, but led to stronger internal consistency reliability as well as improved item discrimination. Implications for test design and student engagement in educational measurement are discussed.

Many preschool agencies nationwide continue to experience closures and/or conversions to virtual or hybrid instruction due to the ongoing coronavirus disease 2019 (COVID-19) pandemic. Despite the importance of understanding young children's learning and development during the COVID emergency, limited knowledge exists on adaptable practices for assessing young children during the pandemic. We assess the learning of 336 Head Start children across four states and three different time periods during the 2020 to 2021 school year, using adaptations of traditionally in-person assessments of early numeracy, early literacy, and executive functioning. In doing so, we distill early lessons for the field from the application of a novel, virtual assessment method with the early childhood population. This article describes the adaptations of assessment administration for virtual implementation and incorporation of feedback into continued virtual delivery of assessments. Applications and limitations in broader contexts are discussed.

Assessment is prevalent throughout all levels of education in the United States. Even though educators are familiar with the idea of assessing students, familiarity does not necessarily ensure assessment literacy, or data-based decision making (DBDM) knowledge. Assessment literacy and DBDM are critical in education, and early childhood education in particular, to identify and intervene on potential barriers to students' development. Assessment produces data and evidence educators can use to inform intervention and instructional decisions to improve student outcomes. Given this importance and educators' varying levels of assessment literacy and DBDM knowledge, researchers, and educators should be willing to meet in the middle to support these practices and improve student outcomes. We provide perspective for half of the equation--how researchers can contribute--by addressing important considerations for the design and development of assessment measures, implications of these considerations for future measures, and a case example describing the design, and development of an assessment tool created to support DBDM for educators in early childhood education.

Gram-positive bacteria assemble pili (fimbriae) on their surfaces to adhere to host tissues and to promote polymicrobial interactions. These hair-like structures, although very thin (1 to 5 nm), exhibit impressive tensile strengths because their protein components (pilins) are covalently crosslinked together via lysine-isopeptide bonds by pilus-specific sortase enzymes. While atomic structures of isolated pilins have been determined, how they are joined together by sortases and how these interpilin crosslinks stabilize pilus structure are poorly understood. Using a reconstituted pilus assembly system and hybrid structural biology methods, we elucidated the solution structure and dynamics of the crosslinked interface that is repeated to build the prototypical SpaA pilus from Corynebacterium diphtheriae We show that sortase-catalyzed introduction of a K190-T494 isopeptide bond between adjacent SpaA pilins causes them to form a rigid interface in which the LPLTG sorting signal is inserted into a large binding groove. Cellular and quantitative kinetic measurements of the crosslinking reaction shed light onto the mechanism of pilus biogenesis. We propose that the pilus-specific sortase in C. diphtheriae uses a latch mechanism to select K190 on SpaA for crosslinking in which the sorting signal is partially transferred from the enzyme to a binding groove in SpaA in order to facilitate catalysis. This process is facilitated by a conserved loop in SpaA, which after crosslinking forms a stabilizing latch that covers the K190-T494 isopeptide bond. General features of the structure and sortase-catalyzed assembly mechanism of the SpaA pilus are likely conserved in Gram-positive bacteria.

Site-specifically modified protein bioconjugates have important applications in biology, chemistry, and medicine. Functionalizing specific protein side chains with enzymes using mild reaction conditions is of significant interest, but remains challenging. Recently, the lysine-isopeptide bond forming activity of the sortase enzyme that builds surface pili in Corynebacterium diphtheriae (CdSrtA) has been reconstituted in vitro. A mutationally activated form of CdSrtA was shown to be a promising bioconjugating enzyme that can attach Leu-Pro-Leu-Thr-Gly peptide fluorophores to a specific lysine residue within the N-terminal domain of the SpaA protein (NSpaA), enabling the labeling of target proteins that are fused to NSpaA. Here we present a detailed analysis of the CdSrtA catalyzed protein labeling reaction. We show that the first step in catalysis is rate limiting, which is the formation of the CdSrtA-peptide thioacyl intermediate that subsequently reacts with a lysine ε-amine in NSpaA. This intermediate is surprisingly stable, limiting spurious proteolysis of the peptide substrate. We report the discovery of a new enzyme variant (CdSrtAΔ) that has significantly improved transpeptidation activity, because it completely lacks an inhibitory polypeptide appendage ("lid") that normally masks the active site. We show that the presence of the lid primarily impairs formation of the thioacyl intermediate and not the recognition of the NSpaA substrate. Quantitative measurements reveal that CdSrtAΔ generates its cross-linked product with a catalytic turnover number of 1.4 ± 0.004 h-1 and that it has apparent KM values of 0.16 ± 0.04 and 1.6 ± 0.3 mM for its NSpaA and peptide substrates, respectively. CdSrtAΔ is 7-fold more active than previously studied variants, labeling >90% of NSpaA with peptide within 6 h. The results of this study further improve the utility of CdSrtA as a protein labeling tool and provide insight into the enzyme catalyzed reaction that underpins protein labeling and pilus biogenesis.

Research has shown that the context of practice tasks can have a significant impact on learning, with long-term retention and transfer improving when tasks of different types are mixed by interleaving (abcabcabc) compared with grouping together in blocks (aaabbbccc). This study examines the influence of context via interleaving from a psychometric perspective, using educational assessments designed for early childhood. An alphabet knowledge measure consisting of four types of tasks (finding, orienting, selecting, and naming letters) was administered in two forms, one with items blocked by task, and the other with items interleaved and rotating from one task to the next by item. The interleaving of tasks, and thereby the varying of item context, had a negligible impact on mean performance, but led to stronger internal consistency reliability as well as improved item discrimination. Implications for test design and student engagement in educational measurement are discussed.

Parents play an important role in creating home language environments that promote language development. A nonequivalent group design was used to evaluate the effectiveness of a community-based implementation of LENA Start™, a parent-training program aimed at increasing the quantity of adult words (AWC) and conversational turns (CT). Parent-child dyads participated in LENA Start™ (n=39) or a generic parent education program (n=17). Overall, attendance and engagement in the LENA Start™ program were high: 72% of participants met criteria to graduate from the program. Within-subject gains were positive for LENA Start™ families. Comparison families declined on these measures. However, both effects were non-significant. Between-group analyses revealed small to medium-sized effects favoring LENA Start™ and these were significant for child vocalizations (CV) and CT but not AWC. These results provide preliminary evidence that programs like LENA Start™ can be embedded in community-based settings to promote quality parent-child language interactions.

This study evaluated the extent to which existing measures met standards for a continuous suite of general outcome measures (GOMs) assessing children's early literacy from preschool through early elementary school. The study assessed 316 children from age 3 years (2 years prekindergarten) through Grade 2, with 8 to 10 measures of language, alphabetic principle, phonological awareness, and beginning reading. We evaluated measures at each grade group against six standards for GOMs extracted from earlier work. We found that one measure of oral language met five or six standards at all grade levels, and several measures of phonological awareness and alphabetic principle showed promise across all five grade levels. Results are discussed in relation to ongoing research and development of a flexible and seamless system to assess children's academic progress across time for effective prevention and remediation, as well as theoretical and empirical analyses in early literacy, early reading, and GOMs.

Purpose: This study was conducted in a large Midwestern metropolitan area to examine the language environments at home and in center-based childcare for young children who are living in poverty. We compared child language use and exposure in the home and childcare settings using extended observations with automated Language Environment Analysis to gain a deeper understanding of the environmental factors that may affect change in language outcomes for young children. Method: Thirty-eight children, along with parents (n = 38) and childcare providers (n = 14) across five childcare centers, participated in this study. Each child completed a standardized language assessment and two daylong recordings with Language Environment Analysis to determine the number of adult words, conversational turns, and child vocalizations that occurred in each setting. Data were analyzed at 5-min intervals across each recording. Results: Comparisons between home recordings in this sample and a comparison group showed reliably higher rates of adult words and conversational turns in the home setting. Linear mixed-effects regression models showed significant differences in the child language environments, with the home setting providing higher levels of language input and use. These effects were still meaningful after accounting for the time of day, participant demographic characteristics, and child language ability. Conclusions: Practical implications for supporting child language development across settings are discussed, and suggestions for further research are provided.

Evidence of longitudinal relations between language and early literacy skills in early childhood and later reading (and other) achievement is growing, along with an expanding array of early education programs designed to improve later academic outcomes and prevent, reduce, or close later academic achievement gaps across groups. Assessment systems to support this intervention have been developed, but to date we have little evidence of these systems' outcomes when used at a broad scale in community-based preschool programs. For this broad purpose, two research questions were addressed: (a) How much progress do children make on language and early literacy skills over the course of one school year? and (b) What is the relationship between child characteristics, baseline performance, and growth on language and early literacy skills? Results indicated growth over time for all measures and relations between child age, gender, and free-or-reduced-price status and students' performance at the beginning of the school year, but (with one exception) no relation between these covariates and growth over time. Discussion centers on current status of language and early literacy assessment in early childhood education as well as needs and issues to be addressed in future research and program development.

Proteins that are site-specifically modified with peptides and chemicals can be used as novel therapeutics, imaging tools, diagnostic reagents and materials. However, there are few enzyme-catalyzed methods currently available to selectively conjugate peptides to internal sites within proteins. Here we show that a pilus-specific sortase enzyme from Corynebacterium diphtheriae (CdSrtA) can be used to attach a peptide to a protein via a specific lysine-isopeptide bond. Using rational mutagenesis we created CdSrtA3M, a highly activated cysteine transpeptidase that catalyzes in vitro isopeptide bond formation. CdSrtA3M mediates bioconjugation to a specific lysine residue within a fused domain derived from the corynebacterial SpaA protein. Peptide modification yields greater than >95% can be achieved. We demonstrate that CdSrtA3M can be used in concert with the Staphylococcus aureus SrtA enzyme, enabling dual, orthogonal protein labeling via lysine-isopeptide and backbone-peptide bonds.

Covalently cross-linked pilus polymers displayed on the cell surface of Gram-positive bacteria are assembled by class C sortase enzymes. These pilus-specific transpeptidases located on the bacterial membrane catalyze a two-step protein ligation reaction, first cleaving the LPXTG motif of one pilin protomer to form an acyl-enzyme intermediate and then joining the terminal Thr to the nucleophilic Lys residue residing within the pilin motif of another pilin protomer. To date, the determinants of class C enzymes that uniquely enable them to construct pili remain unknown. Here, informed by high-resolution crystal structures of corynebacterial pilus-specific sortase (SrtA) and utilizing a structural variant of the enzyme (SrtA2M), whose catalytic pocket has been unmasked by activating mutations, we successfully reconstituted in vitro polymerization of the cognate major pilin (SpaA). Mass spectrometry, electron microscopy, and biochemical experiments authenticated that SrtA2M synthesizes pilus fibers with correct Lys-Thr isopeptide bonds linking individual pilins via a thioacyl intermediate. Structural modeling of the SpaA-SrtA-SpaA polymerization intermediate depicts SrtA2M sandwiched between the N- and C-terminal domains of SpaA harboring the reactive pilin and LPXTG motifs, respectively. Remarkably, the model uncovered a conserved TP(Y/L)XIN(S/T)H signature sequence following the catalytic Cys, in which the alanine substitutions abrogated cross-linking activity but not cleavage of LPXTG. These insights and our evidence that SrtA2M can terminate pilus polymerization by joining the terminal pilin SpaB to SpaA and catalyze ligation of isolated SpaA domains in vitro provide a facile and versatile platform for protein engineering and bio-conjugation that has major implications for biotechnology.

Early comprehension is an important, but not well-understood, contribution to early literacy and language development. Specifically, research regarding the nature of skills representative of early comprehension, including how they contribute to later reading success, is needed to support best practices to adequately prepare students. This article describes the process involved in the creation and refinement of the newly developed comprehension Individual Growth and Development Indicators (IGDIs 2.0). Two theoretical models of early comprehension are discussed to highlight the inherent complexity of this domain. Results of three studies are presented: Study 1 outlines the initial piloting process, Study 2 represents a larger-scale investigation, and Study 3 describes further field testing and reveals the final IGDI 2.0 comprehension candidate: Which One Doesn't Belong (WODB). Results indicated WODB out-performed the other candidate measures across psychometric and pragmatic criteria. The utility of the WODB task within a Response to Intervention (RTI) framework is also discussed. [This article was published in "Assessment for Effective Intervention" (EJ1050548).]

Learning to read is one of the most important indicators of academic achievement. The development of early literacy skills during the preschool years is associated with improved reading outcomes in later grades. One of these skill areas,phonological awareness, shows particular importance because of its strong link to later reading success. Presented here are two studies that describe the development and revision of four measures of phonological awareness skills: Individual Growth and Development Indicators Sound Blending, Syllable Sameness, Rhyming, and Alliteration 2.0. The authors discuss the measure development process, revision, and utility within an early childhood Response to Intervention framework. [This article was published in "Journal of Learning Disabilities," (EJ1070909).]

Ongoing expansion of early education services in the United States is often rooted in these programs' contribution to development that promotes later academic and behavioral competence. Multi-tiered systems of support (MTSS, sometimes referred to as Response to Intervention) represent one increasingly common resource to promote desired outcomes for all children. MTSS requires seasonal screening of all students and progress monitoring of those selected for more intensive intervention. This study explores development and evaluation of measures for these uses, designed specifically to assess the language and early literacy development of 3-year-old children. Results from assessment of 449 children describe measure reliability, growth across three seasonal screenings, development of criterion-referenced benchmarks, and variations in growth for children at different levels of initial performance. Results are discussed in terms of normative versus criterion-referenced standards for building MTSS assessment systems as well as future directions for research, policy, and practice. [ABSTRACT FROM AUTHOR]

Language skills developed during preschool contribute strongly to later reading and academic achievement. Effective preschool assessment and intervention should focus on core components of language development, specifically oral language skills. The Early Language and Literacy Individual Growth and Development Indicators (IGDIs) are a set of measures that have demonstrated utility in language and early literacy assessment, evaluation, and intervention studies. The purpose of this article is to describe two studies conducted to build on the existing oral language IGDI, Picture Naming, to increase utility for instructional decision making, particularly within an early childhood Response to Intervention framework. Study 1 outlines the initial development and piloting of potential measures and Study 2 describes the revision and continued analysis of the most promising measures. Results of Study 1 and Study 2 indicate that Picture Naming has continued utility as a measure of oral language skill development and that one newly developed oral language IGDI, Definitional Vocabulary, has potential utility. [This paper was published in "Assessment for Effective Intervention" (EJ1033214).]

Studies have shown that item difficulty can vary significantly based on the context of an item within a test form. In particular, item position may be associated with practice and fatigue effects that influence item parameter estimation. The purpose of this research was to examine the relevance of item position specifically for assessments used in early education, an area of testing that has received relatively limited psychometric attention. In an initial study, multilevel item response models fit to data from an early literacy measure revealed statistically significant increases in difficulty for items appearing later in a 20-item form. The estimated linear change in logits for an increase of 1 in position was 0.024, resulting in a predicted change of 0.46 logits for a shift from the beginning to the end of the form. A subsequent simulation study examined impacts of item position effects on person ability estimation within computerized adaptive testing. Implications and recommendations for practice are discussed.

Two studies investigated the validity of a set of 15 general growth outcomes for young children by conducting a survey of parents of children with and without disabilities and early childhood and elementary professionals. Large proportions of both groups rated all of the outcomes as either critically or very important. (Contains references.) (CR)