Bacteria often cope with environmental stress by inducing alternative sigma (σ) factors, which direct RNA polymerase to specific promoters, thereby inducing a set of genes called a regulon to combat the stress. To understand the conserved and organism-specific functions of each σ, it is necessary to be able to predict their promoters, so that their regulons can be followed across species. However, the variability of promoter sequences and motif spacing makes their prediction difficult. We developed and validated an accurate promoter prediction model for Escherichia coli σE, which enabled us to predict a total of 89 unique σE-controlled transcription units in E. coli K-12 and eight related genomes. σE controls the envelope stress response in E. coli K-12. The portion of the regulon conserved across genomes is functionally coherent, ensuring the synthesis, assembly, and homeostasis of lipopolysaccharide and outer membrane porins, the key constituents of the outer membrane of Gram-negative bacteria. The larger variable portion is predicted to perform pathogenesis-associated functions, suggesting that σE provides organism-specific functions necessary for optimal host interaction. The success of our promoter prediction model for σE suggests that it will be applicable for the prediction of promoter elements for many alternative σ factors.

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The purpose of this study was to evaluate speech therapy for functional misarticulations and to determine the measures which predict improvement in speech, language, and listening. The following factors appeared predictive: (a) occupational status of the fathers and word recognition; (b) mental age and improvement in word recognition, auditory discrimination, and articulation; (c) stimulability of sounds and improvement in articulation; (d) auditory skills and improvement in connected speech.

This article provides a critical assessment of evidence for the claim of experienced clinicians that proper body alignment will ameliorate the feeding problems of patients with cerebral palsy and related neuromotor disorders and reduce the risk of aspiration. While there is evidence that alignment reduces extensor tone and improves feeding, further research is needed to determine whether this population's high risk for aspiration can be reduced by alignment.