Kinetically Tunable, Active Auxetic, and Variable Recruitment Active Textiles from Hierarchical Assemblies

2021 ◽  
pp. 2000825
Author(s):  
Rachael Granberry ◽  
Justin Barry ◽  
Brad Holschuh ◽  
Julianna Abel
Keyword(s):  
Variable Recruitment

Effects of flow heterogeneity on the measurement of capillary exchange in the lung

1995 ◽  
Vol 79 (5) ◽  
pp. 1449-1460 ◽  
Author(s):  
S. D. Caruthers ◽  
T. R. Harris ◽  
K. A. Overholser ◽  
N. A. Pou ◽  
R. E. Parker
Keyword(s):  
Effective Diffusivity ◽  
Relative Dispersion ◽  
Flow Heterogeneity ◽  
Homogeneous Flow ◽  
Capillary Recruitment ◽  
Flow Models ◽  
Capillary Exchange ◽  
Variable Recruitment ◽  
Area Product ◽  
Recruitment Model

The effects of flow heterogeneity on the measurement of transcapillary escape of small molecules for perfused in situ sheep lungs were evaluated. Lungs were studied at five flows (1.5–5.0 l/min) ranging from zone 1 to zone 3 conditions. At each flow, multiple indicator-dilution curves were collected using 14C-labeled urea (U) or butanediol (B) as the diffusing tracer, and radiolabeled 15-microns microspheres were injected. The lungs were removed, dried, sectioned, weighed, and counted for microsphere radioactivity. Flow heterogeneity expressed as relative dispersion, decreased with increasing flow, from 0.838 +/- 0.179 (mean +/- SD, n = 8) to 0.447 +/- 0.119 (n = 6). We applied homogeneous flow models of capillary exchange to compute permeability-surface area product (PS) and a related parameter, D1/2S, for diffusing tracers. (D is effective diffusivity of capillary exchange.) PS and D1/2S increased to a maximum with increasing flow, but the ratio of D1/2SU to D1/2SB remained constant. A new model incorporating flow heterogeneity and recruitment (the variable recruitment model) was used. The variable recruitment model described the effects of flow on capillary recruitment, but incorporating heterogeneity into the computation did not alter D1/2S values from those computed assuming homogeneous flow.

Variable recruitment in bundles of miniature pneumatic artificial muscles

2016 ◽  
Vol 11 (5) ◽  
pp. 056014 ◽  
Author(s):  
Sylvie A DeLaHunt ◽  
Thomas E Pillsbury ◽  
Norman M Wereley
Keyword(s):  
Artificial Muscles ◽  
Pneumatic Artificial Muscles ◽  
Variable Recruitment

Low recruitment not mortality limits growth of peripheral populations of Silene spaldingii

Botany ◽  
2014 ◽  
Vol 92 (5) ◽  
pp. 340-347 ◽  
Author(s):  
Peter Lesica
Keyword(s):  
Population Viability ◽  
Plant Population ◽  
Range Limits ◽  
Peripheral Populations ◽  
Vital Rates ◽  
Plateau Region ◽  
Columbia Plateau ◽  
Central Population ◽  
Variable Recruitment ◽  
Eastern Washington

Populations at the periphery of a species range are thought to be less viable than those in the center because they are at the limit of their ecological tolerances. Plant population viability is determined primarily by mortality and recruitment, thus knowing differences in vital rates between central and peripheral populations is key to understanding range limits. Silene spaldingii S. Watson is a long-lived iteroparous plant that occurs throughout the eastern Columbia Plateau region of eastern Washington and adjacent Idaho and Oregon and is disjunct in northwest Montana. I recorded the fate of mapped S. spaldingii plants annually for 10 years in four populations, two from eastern Washington and two from Montana. Recruitment averaged three times higher and relatively constant at two central populations in Washington compared with two peripheral sites in Montana. Mortality was three times higher at one of the central populations compared with the remaining three sites due to vole predation. Vole activity was observed at the second central population but came too late in the study to be certain that it resulted in mortality. Vole predation was not observed in the peripheral populations. My results suggest that peripheral populations of S. spaldingii may only be able to persist as long as predation or other sources of mortality remain low and that intrinsic low and variable recruitment rates coupled with predation may help define the eastern range margin of this species.

Distribution, feeding behaviour, and condition of Cape horse mackerel early life stages, Trachurus capensis, under different environmental conditions in the northern Benguela upwelling ecosystem

2014 ◽  
Vol 72 (2) ◽  
pp. 543-557 ◽  
Author(s):  
S. J. Geist ◽  
A. Kunzmann ◽  
H. M. Verheye ◽  
A. Eggert ◽  
A. Schukat ◽  
...  
Keyword(s):  
Dissolved Oxygen ◽  
Feeding Ecology ◽  
Environmental Conditions ◽  
Early Life ◽  
Early Life History ◽  
Horse Mackerel ◽  
Larval Phase ◽  
Recruitment Success ◽  
Wide Range ◽  
Variable Recruitment

Abstract Early life history (ELH) traits are key to understand variable recruitment success and hence the stock size of marine fish. One of the currently most puzzling ecosystems in this regard is the northern part of the Benguela Current upwelling system off Namibia. Here, populations of the formerly dominant pelagic species, sardine and anchovy, failed to recover during the last three decades after a dramatic decline. In contrast, Cape horse mackerel, Trachurus capensis, maintained a constant population size. Warming of the system and shoaling of hypoxic zones together with feedback loops within an altered foodweb are discussed to be responsible for this regime shift. In this study, we address the role of larval traits for the successful performance of the T. capensis population under the present environmental conditions with the focus on feeding ecology. We investigated seasonal variations of the geographical distribution, growth rate, feeding ecology, and nutritional condition of their ELH stages and examined relationships with water temperature, dissolved oxygen concentration, and micro-zooplankton composition. T. capensis' ELH stages showed a wide spatial and seasonal distribution, a preference for higher water temperatures (18–21°C) and presence over a wide range of dissolved oxygen concentrations (0.13–6.35 ml O2 l−1). Feeding success was high and mainly different groups of Copepoda were targeted, which were strongly size selected. The high dietary importance of micro-copepods during large parts of the larval phase indicates successful exploitation of this food source, which has increased in abundance during the last decade. It also explains observed best nutritional conditions at temperatures between 18 and 21°C, since these small copepods are commonly associated with warmer temperatures. Altogether, these traits enhance the species' probability to encounter suitable environments for the survival of their ELH stages, which is likely to lead to their high recruitment success in the northern Benguela ecosystem.

Biology and Management of Inland Striped Bass and Hybrid Striped Bass

2013 ◽  
Keyword(s):  
Striped Bass ◽  
Population Models ◽  
Model Parameters ◽  
Hybrid Striped Bass ◽  
Time Dynamic ◽  
Management Actions ◽  
Age Structured ◽  
Variable Recruitment ◽  
Yield Time ◽  
Yield Per Recruit

<em>Abstract</em>.—Population models are frequently used to assess stocks and inform management, but use of models for inland striped bass <em>Morone saxatilis</em> fisheries is rare in the literature. We summarize three common types of population models and describe how they could aid management of striped bass and hybrid striped bass fisheries. Yield-per-recruit models are ideal for identifying growth overfishing and optimum size at harvest to maximize yield. Time-dynamic, age-structured models are useful for evaluating effects of variable recruitment on angler catch and effects of temporary changes in model parameters (e.g., fish kills, changes in growth) on model output. Catch-at-age models can be used to measure recruitment to age 1 for inland striped bass fisheries and for quantifying fishing mortality rates. Catch-at-age models can also improve the utility of creel survey data and help evaluate the efficacy of stocking programs by estimating age-1 recruits (from model) per stocked fish (from hatchery). Population models force investigators to be explicit about their hypotheses regarding fisheries systems, identify data gaps, and allow assessment of potential impacts of management actions on the fishery. The examples shown here can be used to improve striped bass and hybrid striped bass monitoring and management.

Variable recruitment fluidic artificial muscles: modeling and experiments

2014 ◽  
Vol 23 (7) ◽  
pp. 074009 ◽  
Author(s):  
Matthew Bryant ◽  
Michael A Meller ◽  
Ephrahim Garcia
Keyword(s):  
Artificial Muscles ◽  
Modeling And Experiments ◽  
Variable Recruitment
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