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Cotton ( Gossypium hirsutum L.) contains a germin-like protein (GLP), GhGLP1, that shows tissue-specific accumulation in fiber. The fiber GLP is an oligomeric, glycosylated protein with a subunit size of approximately 25.5 kDa. Accumulation of GhGLP1 occurs during the period of fiber elongation [4?14 days post-anthesis (DPA)]. During early phases of fiber development (2?4 DPA), GhGLP1 localizes to cytoplasmic vesicles as shown by confocal immunofluorescent microscopy. In slightly older fibers (7?10 DPA), GhGLP1 localizes to the apoplast. In other plants, germins and GLPs have been reported to have enzymatic activities including oxalate oxidase (OxO), superoxide dismutase, and ADP-glucose pyrophosphatase. Cotton fiber extracts did not contain OxO activity, nor did intact fibers stain for OxO activity. A four-step purification protocol involving ammonium sulfate precipitation of a 1.0 M NaCl extract, ion-exchange chromatography on DEAE-Trisacryl M, lectin-affinity chromatography, and gel filtration chromatography resulted in electrophoretically pure GhGLP1. While 1.0 M NaCl extracts from 10?14 DPA fiber contained superoxide dismutase and phosphodiesterase activities, GhGLP1 could be separated from both enzyme activities by the purification protocol. Although a GLP accumulates in the cotton fiber apoplast during cell elongation, the function of this protein in fiber growth and development remains unknown. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine: the type of coating that minimized pipe surface roughness and how the choice of metrological instrument could influence pipe surface roughness data. The internal surface of pipe was coated with either phenolic, modified novalac, epoxy, or nylon material. Roughness of coated pipe was assessed with two linear surface profilers, a Dektak3ST and a Hommel T1000, and a Dimension 3000 atomic force microscope (AFM). Arithmetic roughness (Ra), root mean square roughness (Rq), and mean peak-to-valley height (RZD), were statistically analyzed. The ability of RZD to focus on the extremes of height and depth on the surface made it a significant parameter for detecting features that would affect fluid flow in pipes. [ABSTRACT FROM AUTHOR]