University of Waterloo

About: University of Waterloo is a education organization based out in Waterloo, Ontario, Canada. It is known for research contribution in the topics: Population & Poison control. The organization has 36093 authors who have published 93906 publications receiving 2948139 citations. The organization is also known as: UW & uwaterloo.

Assessment of balance control in humans

Abstract: Balance and posture of the body is essential to most human locomotion. Because humans are bipeds with about 2/3 of their mass located 2/3 of body height from the ground the control system is critical. In the elderly balance control degenerates. Falls represent a major health problem and the fear of falls is the major deterrent to daily mobility. Many measures have evolved to assess balance, varying from crude balance tasks to sophisticated perturbations. This paper summarizes the balance control task as it relates to standing and walking and details current assessment techniques and equipment. Additional information is provided by the authors to demonstrate from an electromyographical and biomechanical perspective the mechanisms and characteristics of the postural control system in both standing and walking.

The identity function of autobiographical memory: Time is on our side

Abstract: Autobiographical memory plays an important role in the construction of personal identity. We review evidence of the bi-directional link between memory and identity. Individuals' current self-views, beliefs, and goals influence their recollections and appraisals of former selves. In turn, people's current self-views are influenced by what they remember about their personal past, as well as how they recall earlier selves and episodes. People's reconstructed evaluations of memories, their perceived distance from past experiences, and the point of view of their recollections have implications for how the past affects the present. We focus on how people's constructions of themselves through time serve the function of creating a coherent--and largely favourable--view of their present selves and circumstances.

pH-Responsive polymers: synthesis, properties and applications

Abstract: pH-Responsive polymers are systems whose solubility, volume, and chain conformation can be manipulated by changes in pH, co-solvent, and electrolytes. This review summarizes recent developments covering synthesis, physicochemical properties, and applications in various disciplines. A variety of synthetic methodologies comprising of emulsion polymerization and living radical polymerization techniques are described, and some of their salient features are highlighted. Several polymeric systems, such as homopolymers, block copolymers, microgels, hydrogels and polymer brushes at interfaces are reviewed, where important characteristics that govern their behavior in solutions are described. Potential applications of these systems in controlled drug delivery, personal and home care, industrial coatings, biological and membrane science, viscosity modifiers, colloid stabilization, and water remediation, are discussed.

An eddy cell model of mass transfer into the surface of a turbulent liquid

Abstract: Experimental gas absorption studies for bubbles transported in turbulent pipe flow of water strongly indicate that liquid phase controlled mass transfer is due to surface renewal by turbulent eddies. Predictions of transport behavior from the conditions of turbulent flow cannot be made in support of this mechanism because no satisfactory theory of turbulent transport near a gas-liquid interface is available. This work considers a model of the hydrodynamic behavior near the surface which provides a link between the observed mass transfer behavior and the state of the turbulent field. In this model, the very small scales of turbulent motion are considered to be controlling. These motions are idealized, and their flow and mass transfer behavior are solved analytically. The overall result for eddies of various sizes is related to the turbulent energy spectrum by using only the easily accessible parameter ϵ, the energy dissipation rate. This model gives quantitative agreement to within a factor of 2 for three widely different experimental situations including gas-liquid and liquid-solid interfaces. However, the predicted Reynolds number dependence is somewhat higher than the experimental result. The model attempts to clearly define the basic physical process at the interface. Therefore, it indicates the direction for further experimentation needed to clarify the basic relationship between the mass transfer rates in the liquid phase and the hydrodynamic behavior of the turbulent liquid.