Evaluation of the separation characteristics of application-specific (pesticides and dioxins) open-tubular columns for gas chromatography.

The solvation parameter model is used to characterize the retention properties of four application-specific open-tubular columns (Rtx-CLPesticides, Rtx-OPPesticides, Rtx-Dioxin and Rtx-Dioxin2) at five equally spaced temperatures over the range 60-140 degrees C. Cluster analysis is used to compare the system constants to a database of forty open-tubular columns characterized according to the same method. System constants differences and retention factor correlation plots are then used to determine selectivity differences between the application-specific columns and their nearest neighbors identified by cluster analysis.

Is there life after Buckley's formocresol? Part II - Development of a protocol for the management of extensive caries in the primary molar.

Objective: To produce a working clinical protocol for pulp therapy techniques in the extensively carious primary molar.

Introduction: The International Agency for Research on Cancer has recently classified formaldehyde as carcinogenic to human beings. As such, a medicament that can be used to replace formocresol in clinical practice should be identified.

Separation characteristics of phenyl-containing stationary phases for gas chromatography based on silarylene-siloxane copolymer chemistries.

The solvation parameter model is used to characterize the retention properties of five open-tubular column stationary phases (ZB-5 ms, DB-5 ms, DB-XLB, DB-17 ms, and DB-35 ms) based on silarylene-siloxane copolymer chemistries at five equally spaced temperatures over the range 60-140 degrees C. System constant differences and regression models for varied compounds are used to establish the selectivity equivalence of the silarylene-siloxane copolymer stationary phases and to compare their separation characteristics with poly(dimethyldiphenylsiloxane) stationary phases containing a nominally similar concentration of phenyl groups. These studies demonstrate that ZB-5 ms and DB-5 ms are selectivity equivalent.

Is there life after Buckley's Formocresol? Part I -- a narrative review of alternative interventions and materials.

Objectives: (1) To present a narrative review of the currently available alternative interventions and materials to formocresol pulpotomy for the management of extensive caries in the primary molar, and (2) to produce a clinical protocol for pulp therapy techniques in the extensively carious primary molar.

Introduction: The International Agency for Research on Cancer has recently classified formaldehyde as carcinogenic to human beings. Since Buckley's Formocresol contains 19% formaldehyde in its full strength and, therefore, 1% in a 20% dilution, a safer alternative should be identified.

Revised solute descriptors for characterizing retention properties of open-tubular columns in gas chromatography and their application to a carborane-siloxane copolymer stationary phase.

An iteration procedure is used to calculate revised solute descriptors for 103 varied compounds suitable for characterizing the retention properties of stationary phases for gas chromatography using the solvation parameter model. The iteration procedure utilizes a database of retention factors obtained on up to 39 open-tubular columns and up to five temperatures in the range 60-140 degrees C for the 103 solutes. The average of the standard deviation [Sigma(logk(exp)-logk(calc))(2)/(n(c)-1)](0.