Concordia University

About: Concordia University is a education organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Control theory & Population. The organization has 13565 authors who have published 31084 publications receiving 783525 citations. The organization is also known as: Sir George Williams University & Loyola College, Montreal.

Produced Water: Overview of Composition, Fates, and Effects

Abstract: Produced water (formation and injected water containing production chemicals) represents the largest volume waste stream in oil and gas production operations on most offshore platforms. In 2003, an estimated 667 million metric tons (about 800 million m3) of produced water were discharged to the ocean from offshore facilities throughout the world. There is considerable concern about the ocean disposal of produced water, because of the potential danger of chronic ecological harm. Produced water is a complex mixture of dissolved and particulate organic and inorganic chemicals in water that ranges from essentially freshwater to concentrated saline brine. The most abundant organic chemicals in most produced waters are water-soluble low molecular weight organic acids and monocyclic aromatic hydrocarbons. Concentrations of total PAH and higher molecular weight alkyl phenols, the main toxicants in produced water, typically range from about 0.040 to about 3 mg/L. The metals most frequently present in produced water at elevated concentrations, relative to those in seawater, include barium, iron, manganese, mercury, and zinc. Upon discharge to the ocean, produced water dilutes rapidly, often by 100-fold or more within 100 m of the discharge. The chemicals of greatest environmental concern in produced water, because their concentrations may be high enough to cause bioaccumulation and toxicity, include aromatic hydrocarbons, some alkylphenols, and a few metals. Marine animals near a produced water discharge may bioaccumulate metals, phenols, and hydrocarbons from the ambient water, their food, or bottom sediments. The general consensus of the International Produced Water Conference was that any effects of produced water on individual offshore production sites are likely to be minor. However, unresolved questions regarding aspects of produced water composition and its fate and potential effects on the ecosystem remain. Multidisciplinary scientific studies are needed under an ecosystem-based management (EBM) approach to provide information on the environmental fates (dispersion, precipitation, biological and abiotic transformation) and effects of chronic, low-level exposures to the different chemicals in produced water.

Defensive Behavior in Organizations: A Preliminary Model

Abstract: The literature on organizational politics has focused on the proactive promotion of self-interests but has neglected the reactive defense of self-interests. Defensive behaviors are argued to: (1) avoid action, via over-conforming, passing the buck, playing dumb, depersonalizing, smoothing and stretching, and stalling, (2) avoid blame via buffing, playing safe, justifying, scapegoating, misrepresenting, and escalating commitment, and (3) avoid change via resisting change and protecting turf. Organizational antecedents of defensiveness include bureaucratic rationality and various stressors, and individual antecedents include insecurity and anxiety, emotional exhaustion, work alienation, self-monitoring, and low self-efficacy. The effects of defensiveness on the individual, recipients, and organization are discussed, and directions for future research are presented.

Determinants of maximal oxygen uptake in severe acute hypoxia

Abstract: To unravel the mechanisms by which maximal oxygen uptake (V˙o 2 max) is reduced with severe acute hypoxia in humans, nine Danish lowlanders performed incremental cycle ergometer exercise to exhaust...