Modeling soil-root water transport with non-uniform water supply and heterogeneous root distribution

Because they grow away from their substratum to compete for light, plants have to withstand hydrodynamic or aerodynamic drag. Both water and land plants reconfigure in response to this drag, and this is presumed to reduce the risk of mechanical failure. However, there is little unequivocal evidence of drag reduction in large trees as a result of reconfiguration. Land plants must also transport water internally to their tissues, and many have developed xylem tracheids and vessels that help speed up this process. Recent evidence that tree height is limited by water supply suggests that water transport efficiency must be a crucial element in tree design. However, the resistance of many parts of the xylem is still unknown. More focused work is urgently required to shed light on the evolution and ecology of plants in relation to the flow of fluids.

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Enumeration and Identification of Asbestos Fibres in Water

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005264x ◽

1974 ◽

Vol 32 ◽

pp. 526-527 ◽

Cited By ~ 1

Author(s):

O. Mudroch ◽

J. R. Kramer

Keyword(s):

Water Supply ◽

Water Samples ◽

Drainage Basin ◽

Lake Superior ◽

Research Work ◽

List Type ◽

The West ◽

Asbestos Fibre ◽

Amphibole Asbestos

Approximately 60,000 tons per day of waste from taconite mining, tailing, are added to the west arm of Lake Superior at Silver Bay. Tailings contain nearly the same amount of quartz and amphibole asbestos, cummingtonite and actinolite in fibrous form. Cummingtonite fibres from 0.01μm in length have been found in the water supply for Minnesota municipalities.The purpose of the research work was to develop a method for asbestos fibre counts and identification in water and apply it for the enumeration of fibres in water samples collected(a) at various stations in Lake Superior at two depth: lm and at the bottom.(b) from various rivers in Lake Superior Drainage Basin.

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Bacterial biofilm behavior in water-supply lines of dental units

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124811 ◽

1992 ◽

Vol 50 (1) ◽

pp. 882-883

Author(s):

B.D. Tall ◽

K.S. George ◽

R. T. Gray ◽

H.N. Williams

Keyword(s):

Water Supply ◽

Medical Devices ◽

Biofilm Formation ◽

Bacterial Biofilm

Studies of bacterial behavior in many environments have shown that most organisms attach to surfaces, forming communities of microcolonies called biofilms. In contaminated medical devices, biofilms may serve both as reservoirs and as inocula for the initiation of infections. Recently, there has been much concern about the potential of dental units to transmit infections. Because the mechanisms of biofilm formation are ill-defined, we investigated the behavior and formation of a biofilm associated with tubing leading to the water syringe of a dental unit over a period of 1 month.

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