The recombination site dif is the target on the Escherichia coli chromosome of the site-specific recombinases XerC and XerD. The dif/XerC-D system plays a role during the cell cycle, probably by favoring sister chromosome monomerization or separation. A phenomenon of regional control over dif activity, also analyzed in this issue, is demonstrated here by translocation of dif to a series of loci...

this study aimed at investigating differential item functioning (dif) on the special english test of the iranian national university entrance exam (inuee). the effect of gender and subject area was taken into account. the study utilized one-parameter irt model with a sample of 36000 students who sat for the inuee special english test in 2004 and/or 2005. the findings confirmed the presence of d...

The intermingled differentiation and sorting out of Dictyostelium prestalk-O and prespore cells requires the diffusible signaling molecule DIF-1, and provides an example of a spatial information-independent patterning mechanism. To further understand this patterning process, we used genetic selection to isolate mutants in the DIF-1 response pathway. The disrupted gene in one such mutant, dimA(-...

INTRODUCTION We present an ordinal logistic regression model for identification of items with differential item functioning (DIF) and apply this model to a Mini-Mental State Examination (MMSE) dataset. We employ item response theory ability estimation in our models. Three nested ordinal logistic regression models are applied to each item. Model testing begins with examination of the statistical...

This study elaborates the Rasch differential item functioning (DIF) model formulation under the marginal maximum likelihood estimation context. Also, the Rasch DIF model performance was examined and compared with the Mantel–Haenszel (MH) procedure in small sample and short test length conditions through simulations. The theoretically known relationship of the DIF estimators between the Rasch DI...

OBJECTIVES This study was developed to determine contemporary management of digoxin toxicity and clinical outcomes. BACKGROUND Although the use of digoxin in heart failure management has declined, toxicity remains a prevalent complication. METHODS The Premier Perspective Comparative Hospital Database (Premier Inc., Charlotte, North Carolina) was used to retrospectively identify patients dia...

OBJECTIVES To evaluate, by age, the performance of 2 disability measures based on needing help: one using 5 classic activities of daily living (ADL) and another using an expanded set of 14 activities including instrumental activities of daily living (IADL), walking, getting outside, and ADL (IADL/ADL). METHODS Guttman and item response theory (IRT) scaling methods are used with a large (N = 2...

BACKGROUND Pemphigus is a chronic autoimmune bullous disorder characterized by autoantibodies directed against desmoglein 3 and/or 1. Demonstration of intercellular deposition of IgG on the cell surface of keratinocytes by direct immunofluorescence (DIF) of the skin is the gold standard in the diagnosis of pemphigus. Recently, DIF of plucked hair demonstrating intercellular deposition of IgG in...