A Bayesian region of measurement equivalence (ROME) approach for establishing measurement invariance.

Measurement invariance research has focused on identifying biases in test indicators measuring a latent trait across two or more groups. However, relatively little attention has been devoted to the practical implications of noninvariance. An important question is whether noninvariance in indicators or items results in differences in observed composite scores across groups. The current study introduces the Bayesian region of measurement equivalence (ROME) as a framework for visualizing and testing the combined impact of partial invariance on the group difference in observed scores. Under the proposed framework, researchers first compute the highest posterior density intervals (HPDIs)-which contain the most plausible values-for the expected group difference in observed test scores over a range of latent trait levels. By comparing the HPDIs with a predetermined range of values that is practically equivalent to zero (i.e., region of measurement equivalence), researchers can determine whether a test instrument is practically invariant. The proposed ROME method can be used for both continuous indicators and ordinal items. We illustrated ROME using five items measuring mathematics-specific self-efficacy from a nationally representative sample of 10th graders. Whereas conventional invariance testing identifies a partial strict invariance model across gender, the statistically significant noninvariant items were found to have a negligible impact on the comparison of the observed scores. This empirical example demonstrates the utility of the ROME method for assessing practical significance when statistically significant item noninvariance is found. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Identification of the Mind Bomb1 Interaction Domain in Zebrafish DeltaD.

Ubiquitylation promotes endocytosis of the Notch ligands like Delta and Serrate and is essential for them to effectively activate Notch in a neighboring cell. The RING E3 ligase Mind bomb1 (Mib1) ubiquitylates DeltaD to facilitate Notch signaling in zebrafish. We have identified a domain in the intracellular part of the zebrafish Notch ligand DeltaD that is essential for effective interactions with Mib1. We show that elimination of the Mind bomb1 Interaction Domain (MID) or mutation of specific conserved motifs in this domain prevents effective Mib1-mediated ubiquitylation and internalization of DeltaD. Lateral inhibition mediated by Notch signaling regulates early neurogenesis in zebrafish. In this context, Notch activation suppresses neurogenesis, while loss of Notch-mediated lateral inhibition results in a neurogenic phenotype, where too many cells are allowed to become neurons. While Mib1-mediated endocytosis of DeltaD is essential for effective activation of Notch in a neighboring cell (in trans) it is not required for DeltaD to inhibit function of Notch receptors in the same cell (in cis). As a result, forms of DeltaD that have the MID can activate Notch in trans and suppress early neurogenesis when mRNA encoding it is ectopically expressed in zebrafish embryos. On the other hand, when the MID is eliminated/mutated in DeltaD, its ability to activate Notch in trans fails but ability to inhibit in cis is retained. As a result, ectopic expression of DeltaD lacking an effective MID results in a failure of Notch-mediated lateral inhibition and a neurogenic phenotype.

The prevalence of childhood traumatic grief--a comparison of violent/sudden and expected loss.

The purpose of this study was to examine the prevalence of childhood traumatic grief (CTG) and posttraumatic stress disorder (PTSD) symptoms in parentally bereaved children and compare scores between those who had lost a parent to a sudden/violent death and those who had lost a parent to an expected death. A sample of 158 parentally bereaved children ages 7-16 completed the Extended Grief Inventory (EGI); 127 of those also completed the UCLA PTSD Index. A large number of children were experiencing CTG symptoms at moderate and severe levels. There was no significant difference in EGI or UCLA PTSD Index scores between the two types of losses. Findings are discussed in relation to trauma theory, research on parentally bereaved children and implications for practice.

Kindergarten literacy assessment of English Only and English language learner students: An examination of the predictive validity of three phonemic awareness measures.

The study assessed the ability of English phonemic awareness measures to predict kindergarten reading performance and determine factors that contributed to growth trajectories on those measures for English Only (EO) and English language learner (ELL) students. Using initial sound fluency (ISF), phoneme segmentation fluency (PSF), and a combined phoneme segmentation task (CPST), students' beginning of kindergarten scores were used to predict end-of-kindergarten Nonsense Word Fluency (NWF) and reading (WRMT-R/NU). Regression analyses revealed that ISF and CPST early in kindergarten predicted variance in NWF and WRMT-R/NU. PSF did not predict reading performance over ISF or CPST. While gender was a significant factor in the growth curves across the measures, results revealed no significant difference for EO and ELL students.

Upper vs lower extremity arterial function after spinal cord injury.

BACKGROUND/OBJECTIVE: The purpose of the study was to determine whether arterial diameter, flow-mediated dilatation (FMD), and arterial range are affected by spinal cord injury (SCI). We assessed arm (radial) and leg (posterior-tibial) arteries that are comparable in size and function to determine whether (a) arterial function is reduced in individuals with SCI vs nondisabled subjects and (b) decrements to SCI arterial function are greater in the legs vs arms. PARTICIPANTS: Eighteen men with chronic (9.8 +/- 6.3 years) SCI (T2 to T11; American Spinal Injury Association A) and 13 nondisabled subjects matched for age (33.1 +/- 4.8 vs 29.8 +/- 8.2 years old, respectively), height, and weight (BMI = 25.3 +/- 5.8 vs 26.6 +/- 5.5 kg/m2, respectively). METHODS: Radial and posterior tibial artery B-mode ultrasound images were continuously captured to measure resting diameter, occluded diameter, and postischemic diameters. Hierarchical linear modeling accounted for the nested experimental design. RESULTS: Individuals with SCI have lower systemic (arm + leg) FMD than nondisabled subjects (9.3% vs 12.3%, respectively; P= 0.035), primarily because of reduced leg FMD (11.5 +/- 3.1% vs 7.0 +/- 2.8% for SCI arms vs legs, respectively; P = 0.010). Persons with SCI also had lower arterial range than nondisabled subjects (0.79 vs 1.00 mm, respectively; P = 0.043), primarily because of the legs (0.81 +/- 0.09 vs 0.56 +/- 0.11 mm for SCI arms vs legs, respectively; P = 0.030). CONCLUSION: Leg arterial function seems to deteriorate at greater rates compared to the arms for individuals with SCI. Interventions to improve cardiovascular health should include measurements taken in the legs.

Mind bomb is a ubiquitin ligase that is essential for efficient activation of Notch signaling by Delta.

Lateral inhibition, mediated by Notch signaling, leads to the selection of cells that are permitted to become neurons within domains defined by proneural gene expression. Reduced lateral inhibition in zebrafish mib mutant embryos permits too many neural progenitors to differentiate as neurons. Positional cloning of mib revealed that it is a gene in the Notch pathway that encodes a RING ubiquitin ligase. Mib interacts with the intracellular domain of Delta to promote its ubiquitylation and internalization. Cell transplantation studies suggest that mib function is essential in the signaling cell for efficient activation of Notch in neighboring cells. These observations support a model for Notch activation where the Delta-Notch interaction is followed by endocytosis of Delta and transendocytosis of the Notch extracellular domain by the signaling cell. This facilitates intramembranous cleavage of the remaining Notch receptor, release of the Notch intracellular fragment, and activation of target genes in neighboring cells.

T cell receptor transgenic mice recognizing the immunodominant epitope of the Torpedo californica acetylcholine receptor.

Myasthenia gravis (MG) is an autoimmune disease caused by T cell-dependent antibody-mediated reduction of acetylcholine receptors (AChR) at the neuromuscular junction. Immunization of animals with Torpedo californica AChR (TAChR) results in an experimental model of MG. We used the variable regions of alpha and beta T cell receptor (TCR) genes recognizing an immunodominant peptide containing amino acids 146-162 from the alpha subunit of TAChR presented in the context of I-A(b) to generate TCR-transgenic mice. We found that the transgenic TCR was strongly positively selected and that transgenic T cells proliferated robustly to the immunodominant peptide and TAChR. Unexpectedly, there was a variable paucity of B cells in the blood and spleen from transgenic mice, which averaged about 16% of peripheral blood lymphocytes, compared to 55% in wild-type B6 mice. Unselected transgenic mice immunized with TAChR exhibited weak anti-TAChR antibody responses. However, transgenic mice selected to have relatively higher B cell numbers produced anti-TAChR titers equal to B6 mice and a predominance of Th1-induced antibody isotypes were observed in certain experiments. The incidence and severity of clinical disease was variable following immunizations. These mice should be useful for studying the pathogenesis and treatment of MG.