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Adenylyl cyclases are generally thought to be transmembrane-, G-protein-, and forskolin-responsive proteins, but a nontransmembrane, soluble adenylyl cyclase (sAC) 2 has been identified (1). Mammalian sAC is not activated by G-proteins or forskolin (1) but by HCO 3 Ϫ /CO 2 in a pH-independent manner (2, 3) and by Ca 2ϩ , which synergizes with HCO 3 Ϫ (4). sAC expression has been described in many human tissues (5). We have shown that it is expressed in the airway epithelium, where it represents the only known adenylyl cyclase localized to cilia (6). sAC is important for flagellar beating in sperm (7-9), and we have shown its importance for regulating ciliary beating in human airway epithelia via cAMP production upon stimulation with HCO 3 Ϫ /CO 2 (6). There are different sources of luminal bicarbonate in the airways: it can be secreted from submucosal glands and ciliated cells (10) and can also be produced de novo from CO 2 and H 2 O by locally secreted carbonic anhydrase (11). Two proteins responsible for transporting HCO 3 Ϫ into cells, Slc26a9 (12, 13) and CFTR (14), have been described in the apical membrane of airway epithelial cells. Slc26a9 is mainly a chloride channel with very low bicarbonate permeability (12); thus, the major apical HCO 3 Ϫ exchange in human airways occurs likely through CFTR (14) or is dependent on it.In 1989, the CFTR gene was linked to cystic fibrosis (15). Initial attempts to localize the protein in the airways were based on mRNA in situ hybridization and pinpointed expression mainly to submucosal gland acini (16). Significant expression of CFTR was more recently also shown in the apical membrane of ciliated cells from healthy human beings, whereas CFTR was absent in the apical membrane of cells from CF patients homozygous for the ⌬F508 mutation (17). Expression of human CFTR (driven by the ciliated cell-specific promoter foxj1) in the trachea of a CF mouse model confirmed targeting of CFTR to the apical membrane of ciliated cells while restoring forskolinstimulated chloride secretion (18). Electrolyte conductance through CFTR is usually associated with chloride transport, but bidirectional conductance of bicarbonate through CFTR has also been demonstrated and is thought to be important in the airway and in pancreatic ducts (14, 19 -21). Regulation of HCO 3 Ϫ transport through CFTR has been related to sAC in Calu3 cells, an airway epithelial cell line (22), and in corneal endothelium (23), but there are no reports of the influence of diminished bicarbonate transport through CFTR on the activity of sAC in primary airway epithelial cells, especially as it * This work was supported, in whole or in part, by National Institutes of Health

Purpose The purpose of this paper is to understand young children’s knowledge of visual literacy elements as well as their ability to comprehend newly introduced visual literacy concepts. The study also examined existing support for visual literacy programs from parents and educators. Design/methodology/approach The study explored the knowledge of basic visual literacy elements of young children enrolled in two private schools in the New York City metropolitan area. The authors interviewed 17 children, aged four to six years old, about fine art paintings using a semi-structured interview format. Children’s responses were qualitatively analyzed to determine their initial level of visual literacy and their ability to learn and retain the concepts of visual literacy after receiving basic instruction. The children’s educators and parents completed online questionnaires that were quantitatively analyzed to determine their level of support for visual literacy programs. Findings The findings show that young children exhibited extensive knowledge of simple visual literacy elements (color, shape, line), and limited understanding of more abstract elements (perspective and salience). Children’s knowledge of visual elements improved after instruction. Parents and educators expressed support for incorporating visual literacy instruction in early childhood education. Research limitations/implications The study relied on a sample of children and adults drawn from two private schools. The sample’s demographics might have affected study findings. More studies are needed using a larger and more diverse sample. Practical implications The study suggests that young children are ready to receive instruction on visual literacy elements using art images. Children reacted positively to the images and were engaged in the discussions about them, supporting the use of fine art paintings as an instrument to introduce visual literacy concepts to young children. Survey of children’s parents and teachers indicated strong interest in, and support for such programs. Social implications With the increase of visual information production and consumption, it is important to introduce visual literacy early in life. The study advances research in methods for developing visual literacy instruction for young children. Originality/value There are no previously reported studies that have examined pre-kindergarten children’s knowledge of basic visual literacy elements and reactions to visual literacy instruction.

Wnt signaling is essential for the differentiation of airway epithelial cells during development. Here, we examined the role of Wnt signaling during redifferentiation of ciliated airway epithelial cells in vitro at the air liquid interface as a model of airway epithelial repair. Phases of proliferation and differentiation were defined. Markers of squamous metaplasia and epithelial ciliation were followed while enhancing β‐catenin signaling by blocking glycogen synthase kinase 3β with SB216763 and shRNA as well as inhibiting canonical WNT signaling with apical application of Dickkopf 1 (Dkk1). Our findings indicate that enhanced β‐catenin signaling decreases the number of ciliated cells and causes squamous changes in the epithelium, whereas treatment with DDk1 leads to an increased number of ciliated cells.

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