Coherent combining of mid-infrared difference frequency generators.

We report what is, to the best of our knowledge, the first experimental demonstration of coherent combining of two mid-infrared difference frequency generators by active phase control in the continuous-wave regime. Using the phase relation that is inherent to the nonlinear process, we are able to phase lock and combine the idler waves by the sole phase control of one of the pump waves. This control is done by an all-fiber electro-optic modulator.

Coherent combining of second-harmonic generators by active phase control of the fundamental waves.

Coherent beam combining by active phase control could be useful for power scaling fiber-laser-pumped optical frequency converters. However, a fast phase modulator operating at the frequency-converted wavelength, a non-standard component, would be necessary. Fortunately, nonlinear conversion processes rely on a phase-matching condition allowing for indirect phase control using standard phase modulators.

Environmental contamination with methotrexate in Canadian community pharmacies.

Objectives: To evaluate environmental contamination with methotrexate, cyclophosphamide, and ifosfamide in Quebec, Canada, community pharmacies and to describe hazardous drug handling practices in these pharmacies.

Methods: Three standardized sites were sampled in each participating community pharmacy. Samples were analyzed for the presence of cyclophosphamide, ifosfamide, and methotrexate by high-performance liquid chromatography tandem mass spectrometry.

Microsecond fiber laser pumped, single-frequency optical parametric oscillator for trace gas detection.

We report on the first microsecond doubly resonant optical parametric oscillator (OPO). It is based on a nested cavity OPO architecture allowing single longitudinal mode operation and low oscillation threshold (few microjoule). The combination with a master oscillator-power amplifier fiber pump laser provides a versatile optical source widely tunable in the 3.

Multicenter study of environmental contamination with antineoplastic drugs in 33 Canadian hospitals.

Purpose: No occupational exposure limit exists for antineoplastic drugs. The main objective of this study was to describe environmental contamination with cyclophosphamide, ifosfamide and methotrexate in pharmacy and patient care areas of Canadian hospitals in 2012. The secondary objective was to compare the 2012 environmental monitoring results with the 2008-2010 results.

Environmental contamination with hazardous drugs in quebec hospitals.

Background: Since publication of the US National Institute for Occupational Safety and Health alert on hazardous drugs in 2004, many health care organizations have reviewed their procedures for handling hazardous drugs. Occupational exposure may occur when handling, compounding, or administering a drug considered to be hazardous, at any stage from storage to waste management.

Objectives: To describe environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in pharmacy and patient care areas of Quebec hospitals.

Picosecond tunable mode locking of a Cr2+:ZnSe laser with a nonlinear mirror.

We report on a nonlinear mirror (NLM) scheme that enables, for the first time to the best of our best knowledge, tunable mode locking of a Cr2+:ZnSe laser in the picosecond regime. The NLM-used as the output coupler of the laser cavity-consists of a periodically poled lithium niobate (PPLN) crystal with a fan-out grating coupled with a dichroic mirror and a wedged dispersive YAG plate. The Cr2+:ZnSe laser, pumped by a CW thulium-doped fiber laser, delivers 85 ps pulses at a repetition rate of 220 MHz with a 300 mW average power.

Management of thermal effects in high-repetition-rate pulsed optical parametric oscillators.

We report on the investigation of thermal effects in high-repetition-rate pulsed optical parametric oscillators emitting in the mid-IR. We find that the thermal load induced by the nonresonant idler absorption plays a critical role in the emergence of thermally induced bistability. We then demonstrate a significant improvement of the conversion efficiency (more than 30%) when a proper axial temperature gradient is applied to the nonlinear crystal by use of a two-zone temperature-controlled oven.

Picosecond synchronously pumped ZnGeP2 optical parametric oscillator.

We report on the experimental operation of a picosecond, singly resonant, synchronously pumped optical parametric oscillator (SPOPO) based on a ZnGeP(2) (ZGP) crystal. The ZGP SPOPO is pumped with the idler radiation from a diffraction-grating-tuned periodically poled lithium niobate SPOPO emitting a continuous picosecond pulse train (Delta tau approximately 8 ps, f=76 MHz). The noncritically 90 degree phase-matched ZGP SPOPO is tuned in the 3.

Evaluation of the usefulness of an oxycodone immunoassay in combination with a traditional opiate immunoassay for the screening of opiates in urine.

Oxycodone is a semisynthetic opioid analgesic largely prescribed for post-operative and chronic pain management. The introduction of a slow release formulation of oxycodone has led to its frequent abuse and to an increase in emergency cases related to oxycodone overdose. Until recently, oxycodone testing has been confined to gas chromatography-mass spectrometry (GC-MS) analysis because the widely used automated opiate immunoassays poorly react to this compound.

Pilot study comparing the efficacy of two cleaning techniques in reducing environmental contamination with cyclophosphamide.

Objective: Compare the efficacy of the cleaning technique usually employed in our healthcare facility to eliminate environmental contamination with cyclophosphamide with that of the Surface Safe commercial kit.

Methods: This is a three-step evaluative and comparative study involving: (i) the voluntary contamination of the surface of a hood with a pre-established quantity of cyclophosphamide (20,000,000 ng), (ii) the cleaning of the work surface of the hood using a cleaning technique usually employed in our healthcare facility or that of the product Surface Safe, and (iii) the quantification of cyclophosphamide detected on the work surface. The usual cleaning technique involves the use of a mixture of 0.

High-energy single-longitudinal mode nearly diffraction-limited optical parametric source with 3 MHz frequency stability for CO2 DIAL.

We report on a 2.05 microm nanosecond master oscillator power amplifier optical parametric source for CO2 differential-absorption lidar. The master oscillator consists of an entangled-cavity nanosecond optical parametric oscillator based on a type II periodically poled lithium niobate crystal that provides highly stable single-longitudinal-mode radiation.

Evaluation of surface contamination in a hospital hematology--oncology pharmacy.

Objective: To describe environmental contamination with hazardous drugs in a hospital pharmacy setting before and after reorganizing a hematology- oncology satellite pharmacy.

Methods: This is a descriptive study of surface contamination with cyclophosphamide, ifosfamide, and methotrexate in two hematology-oncology satellite pharmacies. In order to measure surface contamination with hazardous drugs, samples from four distinct measurement sites within the pharmacy were taken in each of the two phases (pre-and postphases) using a sampling procedure and an analytical method modified from Larson et al.

Cyclophosphamide contamination observed on the external surfaces of drug vials and the efficacy of cleaning on vial contamination.

Objective: Evaluate contamination on the external surfaces of cyclophosphamide vials available on the Canadian market during storage in pharmacy departments and the efficacy of decontaminating the external surfaces of vials using various cleaning techniques.

Methods: The study consisted of three phases: the quantification of cyclophosphamide on the external surfaces of 10 vials of Procytox and 10 vials of Cytoxan available on the Canadian market with or without prewashing (Phases I and II) and the quantification of cyclophosphamide on the surfaces of 30 deliberately contaminated empty sterile vials cleaned using three different washing techniques (Phase III). The quantification of cyclophosphamide was conducted using ultra performance liquid chromatography with tandem mass spectrometry.

Unproven ingestion: an unrecognized bias in toxicological case series.

Background: Case series of ingestion in preschool children may include patients without significant exposure if the substance is not measured.

Methods: In order to evaluate the unproven ingestion bias, we conducted, between January 2000 and June 2004, a retrospective analysis of a poison control center-based series of children <6 years old with a history of toxic methanol or ethylene glycol ingestion.

Results: Over the 54 month period, 115 children were referred to obtain a level.

Active mode locking of continuous-wave doubly and singly resonant optical parametric oscillators.

We report on what we believe to be the first active mode locking of near-degenerate, doubly and singly resonant cw-pumped optical parametric oscillators (OPOs). We show experimentally that a steady-state regime of short pulses is reached in a few tens of microseconds under cw pumping. The oscillation buildup dynamics of both OPOs is also explored, evidencing an unusual transient behavior in the mode-locking process.

Actively mode-locked optical parametric oscillator.

We report on what we believe to be the first demonstration of active mode locking of an optical parametric oscillator. An acousto-optic modulator is inserted into a nearly degenerate (approximately 1064 nm) and doubly resonant optical parametric oscillator based on periodically poled LiNbO3 and pumped with the second harmonic of a quasi-continuous-wave single-frequency Nd:YAG laser. When the modulation frequency is matched to the free spectral range of the cavity (120 MHz), a pulsed regime is observed, with pulse durations as short as 700 ps.

Generation of mid-infrared radiation by self-difference frequency mixing in chromium-doped zinc selenide.

We report what we believe to be the first demonstration of mid-infrared generation (approximately 9 microm) by self-difference frequency generation in Fresnel birefringence quasi-phase-matched Cr:ZnSe laser slabs.

Vitamin A concentration in umbilical cord blood of infants from three separate regions of the province of Québec (Canada).

Background: Inuit women from Northern Québec have been shown to consume inadequate quantities of vitamin A. This study was conducted to evaluate the prevalence of blood vitamin A deficiency in newborns from 3 distinct populations of the province of Québec.

Methods: 594 newborns were included in this study (375 Inuit newborns from northern Québec (Nunavik), 107 Caucasian and Native newborns from the Lower Northern Shore of the Saint-Lawrence River (LNS) and 112 newborns from Southern Québec where clinical vitamin A deficiency is uncommon).