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Inositol 1,4,5-trisphosphate receptors in Caenorhabditis elegans are encoded by a single gene, itr-1. This provides a powerful system in which to dissect the mechanisms that control the tissue-specific expression of molecules that determine the specificity of calcium signalling. We first identified the Caenorhabditis briggsae orthologue of itr-1, Cbitr-1. Comparison of the two itr-1 genes revealed that the chromosomal organisation, gene structure and predicted cDNA and protein sequences were all conserved. The conserved gene structure supports the hypothesis that the itr-1 gene has three promoters, each of which gives rise to an alternative mRNA and hence unique protein. To test this and to identify the roles of the three putative promoters (pA, pB and pC) in regulating itr-1 expression we fused each promoter to the green fluorescent protein gene and identified their expression patterns. Introduction of these transgenes into C. elegans identified unique and defined patterns of green fluorescent protein expression directed by each promoter: pA directs expression in the pharyngeal terminal bulb, the rectal epithelial cells and vulva; pB directs expression in the motor neurone PDA, the amphid socket cells and the spermatheca; pC directs expression in the spermathecal valve, uterine sheath cells, pharyngeal isthmus and intestine. Thus tissue-specific expression of itr-1 variants is directed by three promoters and this results in adjacent cells in the same tissue containing different inositol trisphosphate receptor isoforms. Within pA, four short regions (pA-A to pA-D) of sequence conservation between C. elegans and C. briggsae were identified. Deletion analysis demonstrated that the region containing pA-C is required for expression in the terminal bulb and rectal epithelial cells and the region containing pA-D is required for expression in the vulva. pA-C includes sequences similar to the binding sites for transcription factors that have been demonstrated to be important in pharyngeal development and gene expression.

This paper describes a method for real-time quantitation of the solvents evaporating from a dryer. The vapor stream in the vacuum line of a dryer was monitored in real time using a fiber optic-coupled acousto-optic tunable filter near-infrared (AOTF-NIR) spectrometer. A balance was placed in the dryer, and mass readings were recorded for every scan of the AOTF-NIR. A partial least-squares (PLS) calibration was subsequently built based on change in mass over change in time for solvents typically used in a chemical manufacturing plant. Controlling software for the AOTF-NIR was developed. The software collects spectra, builds the PLS calibration model, and continuously fits subsequently collected spectra to the calibration, allowing the operator to follow the mass loss of solvent from the dryer. The results indicate that solvent loss can be monitored and quantitated in real time using NIR for the optimization of drying times. These time-based mass loss values have also been used to calculate "dynamic" vapor density values for the solvents. The values calculated are in agreement with values determined from the ideal gas law and could prove valuable as tools to measure temperature or pressure indirectly.

Objective: to evaluate the effectiveness of a reduced-frequency prenatal visit schedule by comparing perinatal outcomes, anxiety and maternal satisfaction with prenatal care., Methods: pregnancy outcomes of infant and maternal morbidity and mortality, anxiety and satisfaction for 81 women receiving prenatal care at a free-standing birthing center according to either an alternative prenatal care visit schedule (APCVS) (n = 43) or the traditional prenatal care visit schedule (TPCVS) (n = 38) were examined in this prospective randomized study. Upon entry into prenatal care, all women were of low obstetrical risk status., Results: major findings revealed no significant differences in selected perinatal outcomes between the two study groups. Women in the APCVS group reported significantly higher levels of satisfaction than women in the TPCVS group on both the satisfaction with provider subscale (F = 5.74, P = .02) and the satisfaction with the prenatal care system subscale (F = 2.01, P = .04). There were no statistically significant differences found in anxiety scores between women in the two study groups., Conclusions: low-risk women who followed the reduced-frequency visit schedule experienced no difference in perinatal outcomes or anxiety. Women in the reduced-frequency (APCVS) group reported an increased level of satisfaction with both provider and the prenatal care system.