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Biomedical subjects

B Rondeau

Publications and source records attributed to B Rondeau.

11 recordsLinked to original sources
PubMed2000

Multiresidue methods using solid-phase extraction techniques for monitoring priority pesticides, including triazines and degradation products, in ground and surface waters.

The review describes the use of solid-phase extraction (SPE) techniques for monitoring priority pesticides in ground and surface waters. The focus is on triazine herbicides and their degradation products. Data concerning the fate, occurrence, properties and extraction of triazines and their degradation products using different SPE techniques are tabulated and discussed.

Chromatography↗
PubMed2000

Oxygen isotopes and emerald trade routes since antiquity

Oxygen isotopic compositions of historical emerald artifacts from the Gallo-Roman period to the 18th century indicate that during historical times, artisans worked emeralds originating from deposits supposedly discovered in the 20th century. In antiquity, Pakistani and Egyptian emeralds were traded by way of the Silk Route. Together with Austrian stones, they were the only source of gem-quality emeralds. Immediately after the discovery of the Colombian mines by Spaniards in the 16th century, a new trade route was established, first via Spain to Europe and India and then directly via the Philippines to India. Since then, Colombian emeralds have dominated the emerald trade, and most of the high-quality emeralds cut in the 18th century in India originated from Colombia.

Journal Article↗
PubMed1998

Mercury distribution in relation to iron and manganese in the waters of the St. Lawrence river.

Waters entering the St. Lawrence River from Lake Ontario and from the Ottawa River have been sampled on a quaternary basis between March 1995 and October 1996. Mercury, iron, manganese, organic carbon and other chemical parameters have been determined in the filtered water (< 0.5 micron) and suspended particles (> 0.5 micron). Average total mercury concentrations (+/- standard deviation, number of determinations) in filtered samples were 1.3 +/- 0.9 pM (39) at the mouth of Lake Ontario and 4.0 +/- 2.3 pM (54) at the outlet of the Ottawa River. The respective average concentrations in suspended particles were 1.1 +/- 0.4 (39) and 0.6 +/- 0.2 (55) nmol g-1. Partial correlation analyses reveal that in the fraction < 0.5 micron--which seems to consist of a significant fraction of colloids--mercury was significantly linked to iron, while in the particulate phase, mercury was related to manganese. Mercury was not correlated with organic carbon. A sorption model on iron and manganese hydroxides is proposed to explain these observations.

Environmental Monitoring↗
PubMedDate not supplied

Risk management.

The purpose of this article is to provide the orthodontic practitioner with a basic understanding of the concept of "Risk Management" so that he/she might be able to minimize the possibility of being sued. There are a number of factors regarding risk management which will also help the prudent practitioner reduce the likelihood of losing a lawsuit should it occur. Many dentists have spent hundreds of hours learning new skills to enhance their service to their patients. My suggestion is that we must also try to increase our risk management skills and our understanding of legal matters if we are to survive the 1990's.

Dental Records↗
PubMedDate not supplied

Twin Block appliance. Part II.

The main purpose of the Twin Block is to advance the mandible and to correct moderate to severe overjets. When the first molars are encouraged to erupt, the Twin Block also results in a partial correction of the overbite. The Rick-A-Nator or Rick-A-Nator 2 Appliances are utilized to hold the mandible in a forward position and also to help erupt the bicuspids to complete the orthopedic correction of the overbite. It is vital that the total treatment time for the active phase with the Twin Block and the support phase with the Rick-A-Nator be a minimum of 15 to 18 months to allow for permanent muscular, skeletal and dental changes to be accomplished.

Child↗