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Storage Effects (storage + effects)

Distribution by Scientific Domains
Life Sciences75%

Selected Abstracts

Effects of water storage in the stele on measurements of the hydraulics of young roots of corn and barley

NEW PHYTOLOGIST, Issue 3 2009
Ankur Joshi
Summary ,,In standard techniques (root pressure probe or high-pressure flowmeter), the hydraulic conductivity of roots is calculated from transients of root pressure using responses following step changes in volume or pressure, which may be affected by a storage of water in the stele. ,,Storage effects were examined using both experimental data of root pressure relaxations and clamps and a physical capacity model. Young roots of corn and barley were treated as a three-compartment system, comprising a serial arrangement of xylem/probe, stele and outside medium/cortex. The hydraulic conductivities of the endodermis and of xylem vessels were derived from experimental data. The lower limit of the storage capacity of stelar tissue was caused by the compressibility of water. This was subsequently increased to account for realistic storage capacities of the stele. ,,When root water storage was varied over up to five orders of magnitude, the results of simulations showed that storage effects could not explain the experimental data, suggesting a major contribution of effects other than water storage. ,,It is concluded that initial water flows may be used to measure root hydraulic conductivity provided that the volumes of water used are much larger than the volumes stored. [source]

Nonvolatile Memory Concepts Based on Resistive Switching in Inorganic Materials

ADVANCED ENGINEERING MATERIALS, Issue 4 2009
Thomas Mikolajick
Abstract Solid state memories play an important role for the electronic systems used in today's information society. The classical approach of charge storage is expected to reach its physical scaling limits very soon. New storage effects are therefore receiving significant interest from industry and academia. In the paper we summarize recent results on resistive switching effects in inorganic materials obtained in the research groups of the authors. We discuss the implications of these results for the suitability of the investigated material systems as well as for the direction of further research. [source]

Sexual vs. asexual reproduction in an ecosystem engineer: the massive coral Montastraea annularis

JOURNAL OF ANIMAL ECOLOGY, Issue 2 2007
NICOLA L. FOSTER
Summary 1Long-lived sedentary organisms with a massive morphology are often assumed to utilize a storage effect whereby the persistence of a small group of adults can maintain the population when sexual recruitment fails. However, employing storage effects could prove catastrophic if, under changing climatic conditions, the time period between favourable conditions becomes so prolonged that the population cannot be sustained solely be sexual recruitment. When a species has multiple reproductive options, a rapidly changing environment may favour alternative asexual means of propagation. 2Here, we revisit the importance of asexual dispersal in a massive coral subject to severe climate-induced disturbance. Montastraea annularis is a major framework-builder of Caribbean coral reefs but its survival is threatened by the increasing cover of macroalgae that prevents settlement of coral larvae. 3To estimate levels of asexual recruitment within populations of M. annularis, samples from three sites in Honduras were genotyped using four, polymorphic microsatellite loci. 4A total of 114 unique genets were identified with 8% consisting of two or more colonies and an exceptionally large genet at the third site comprising 14 colonies. 5At least 70% of multicolony genets observed were formed by physical breakage, consistent with storm damage. 6Our results reveal that long-lived massive corals can propagate using asexual methods even though sexual strategies predominate. [source]

Effects of water storage in the stele on measurements of the hydraulics of young roots of corn and barley

NEW PHYTOLOGIST, Issue 3 2009
Ankur Joshi
Summary ,,In standard techniques (root pressure probe or high-pressure flowmeter), the hydraulic conductivity of roots is calculated from transients of root pressure using responses following step changes in volume or pressure, which may be affected by a storage of water in the stele. ,,Storage effects were examined using both experimental data of root pressure relaxations and clamps and a physical capacity model. Young roots of corn and barley were treated as a three-compartment system, comprising a serial arrangement of xylem/probe, stele and outside medium/cortex. The hydraulic conductivities of the endodermis and of xylem vessels were derived from experimental data. The lower limit of the storage capacity of stelar tissue was caused by the compressibility of water. This was subsequently increased to account for realistic storage capacities of the stele. ,,When root water storage was varied over up to five orders of magnitude, the results of simulations showed that storage effects could not explain the experimental data, suggesting a major contribution of effects other than water storage. ,,It is concluded that initial water flows may be used to measure root hydraulic conductivity provided that the volumes of water used are much larger than the volumes stored. [source]