The Gram-negative soil bacterium Myxococcus xanthus has a complex life cycle that involves vegetative growth and, when nutrients are limiting, formation of spore-containing fruiting bodies. The progression of the developmental cycle depends in part upon the ability of M. xanthus cells to sense and respond to their environment and to coordinate two different motility systems to achieve directed ...

Many Prolog programs are unnecessarily impure because of inadequate means to express syntactic inequality. While the frequently provided built-in dif/2 is able to correctly describe expected answers, its direct use in programs often leads to overly complex and inefficient definitions — mainly due to the lack of adequate indexing mechanisms. We propose to overcome these problems by using a new p...

The reliability and validity of the six traits comprising High Potential Trait Indicator (HPTi) were evaluated using Rasch analysis. Focus was designated to unidimensionality local independence each subscale; fit model; person separation; differential item functioning (DIF). Secondary data, obtained from intellectual property rights holder Thomas International, used for analysis with a sample 1...

Purpose To assess whether a panel of serum pemphigoid autoantibody tests could be used to confirm an immunopathologic diagnosis mucous membrane (MMP) in direct immunofluorescent negative (DIF–) MMP patients. Design Prospective cross-sectional study. Participants Seventy-six patients with multisite 45 matched control participants. Methods Enzyme-linked immunosorbent assays (ELISAs) for BP180 and...

INTRODUCTION There are several studies showing the presence of Differential Item Functioning (DIF) in some items of the Beck Depression Inventory (BDI), when comparing men and women. The presence of a large number of items with DIF in BDI is a severe threat to the validity of measurement of the intensity of depressive symptoms obtained by Item Response Theory (IRT) and to the conclusions based ...

Differential item functioning (DIF) can lead to an unfair advantage or disadvantage for certain subgroups in educational and psychological testing. Therefore, a variety of statistical methods has been suggested for detecting DIF in the Rasch model. Most of these methods are designed for the comparison of pre-specified focal and reference groups, such as males and females. Latent class approache...

This study aims to compare the Wald test and likelihood ratio (LRT) approaches with Classical Test Theory (CTT) Item Response (IRT) based differential item functioning (DIF) detection methods in context of cognitive diagnostic models (CDMs), using TIMSS 2011 dataset as a retrofitting study. CDMs, which have significant potential when determining DIF their contribution validity, can give confide...

Ensuring measurement invariance for students with disabilities is critical fair in large-scale testing. Specific learning disability constitutes the largest group among groups. In this study, it was aimed to examine of Turkish Central Exam Secondary Education according whether or not have a specific disability. 994 diagnosed formed focus group, whilst 1,000 without any constituted reference gro...

Fibreoptic tracheal intubation is a useful technique in patients whose tracheas are dif®cult to intubate. 69 However, there are two major dif®culties with this technique. The ®rst is location of the glottis and insertion of a ®brescope into the trachea. Induction of general anaesthesia (with or without neuromuscular block) causes the soft palate, tongue and epiglottis to approximate to the post...