Orientation-dependent growth rate of crystalline plane study in electrodeposited Ni/Cu superlattice nanowires

Growing degree-days (GDD, °C·days) are an index of ambient thermal energy that relates directly to an ectotherm’s cumulative metabolism but is rarely used to describe growth and development in fish. We applied GDD to length and maturity data from 416 populations of walleye ( Sander vitreus ) from Ontario and Quebec, Canada (mean annual GDD = 1200 to 2300 °C·days). On average, males matured after they had experienced 6900 °C·days and reached 350 mm total length (L) (n = 77 populations), and females matured after 10 000 °C·days and at 450 mm L (n = 70). Across 143 populations, GDD accounted for up to 96% of the variation in the length of immature walleye but also revealed a twofold difference in growth rate that was indicative of variation in food availability. When applied to data from eight populations in which walleye abundances have changed dramatically over time, GDD revealed a 1.3-fold increase in immature growth rate when abundance was low compared with when it was high. Our results both demonstrate the explanatory power of GDD with respect to fish growth and maturity and inform the development of regional management strategies for walleye.

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Density-Dependent Growth Adaptation Kinetics in 3T 3 Cell Populations Following Sudden [Ca2+] and Temperature Changes. A Comparison with SV40-3T3 Cells

Zeitschrift für Naturforschung C ◽

10.1515/znc-1979-3-420 ◽

1979 ◽

Vol 34 (3-4) ◽

pp. 279-283 ◽

Cited By ~ 2

Author(s):

Jürgen van der Bosch ◽

Ilse Sommer ◽

Heinz Maier ◽

Willy Rahmig

Keyword(s):

Growth Rate ◽

Cell Density ◽

Cell Number ◽

Cell Populations ◽

3T3 Cells ◽

Density Dependent ◽

Cell Densities ◽

Dependent Growth ◽

Growth Adaptation ◽

Stationary Cell

Abstract Lowered extracellular [Ca2+] causes low growth rates and low stationary cell densities in 3T3 cell cultures as compared to physiological [Ca2+]. Under otherwise constant conditions the extra cellular [Ca2+] determines a stable stationary cell density, which can be readied by increase of net cell number or decrease of net cell number, depending on cell density at the time of [Ca2+] adjustment. SV40-3T3 cells do not show this [Ca2+] dependency. At 39 °C 3T3 and SV40-3T3 cell populations show an increased growth rate at low cell densities as compared to cell populations at 35 °C. Approaching the stationary density the growth rate of both cell sorts is reduced faster at 39 °C than at 35 °C, leading to lower stationary cell densities at 39 °C than at 35 °C. A temperature change from 39 °C to 35 °C or in the opposite direction can affect the stationary cell density of 3T3 cell populations only if applied before reduction of growth rate by density-dependent growth-inhibiting principles has taken place.

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Cooperative hunting in a discrete predator–prey system

International Journal of Biomathematics ◽

10.1142/s1793524520500631 ◽

2020 ◽

Vol 13 (07) ◽

pp. 2050063

Author(s):

Yunshyong Chow ◽

Sophia R.-J. Jang ◽

Hua-Ming Wang

Keyword(s):

Growth Rate ◽

Discrete Time ◽

Reproductive Number ◽

Model Parameters ◽

Predator Population ◽

Sufficient Condition ◽

Predator Prey ◽

Cooperative Hunting ◽

Prey System ◽

Dependent Growth

We propose and investigate a discrete-time predator–prey system with cooperative hunting in the predator population. The model is constructed from the classical Nicholson–Bailey host-parasitoid system with density dependent growth rate. A sufficient condition based on the model parameters for which both populations can coexist is derived, namely that the predator’s maximal reproductive number exceeds one. We study existence of interior steady states and their stability in certain parameter regimes. It is shown that the system behaves asymptotically similar to the model with no cooperative hunting if the degree of cooperation is small. Large cooperative hunting, however, may promote persistence of the predator for which the predator would otherwise go extinct if there were no cooperation.

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Comment on ACP-2017-658 “Resolving nanoparticle growth mechanisms from size- and time-dependent growth rate analysis”

10.5194/acp-2017-658-rc1 ◽

2017 ◽

Author(s):

Anonymous

Keyword(s):

Growth Rate ◽

Time Dependent ◽

Growth Mechanisms ◽

Nanoparticle Growth ◽

Rate Analysis ◽

Dependent Growth

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Positive density-dependent growth supports costs sharing hypothesis and population density sensing in a manipulative parasite

Parasitology ◽

10.1017/s0031182017001020 ◽

2017 ◽

Vol 144 (11) ◽

pp. 1511-1518 ◽

Cited By ~ 3

Author(s):

MIKHAIL GOPKO ◽

VICTOR N. MIKHEEV ◽

JOUNI TASKINEN

Keyword(s):

Growth Rate ◽

Rainbow Trout ◽

Population Density ◽

Cost Sharing ◽

Positive Density ◽

Diplostomum Pseudospathaceum ◽

Instance Theory ◽

Positive Density Dependence ◽

Study Support ◽

Dependent Growth

SUMMARYParasites manipulate their hosts’ phenotype to increase their own fitness. Like any evolutionary adaptation, parasitic manipulations should be costly. Though it is difficult to measure costs of the manipulation directly, they can be evaluated using an indirect approach. For instance, theory suggests that as the parasite infrapopulation grows, the investment of individual parasites in host manipulation decreases, because of cost sharing. Another assumption is that in environments where manipulation does not pay off for the parasite, it can decrease its investment in the manipulation to save resources. We experimentally infected rainbow trout Oncorhynchus mykiss with the immature larvae of the trematode Diplostomum pseudospathaceum, to test these assumptions. Immature D. pseudospathaceum metacercariae are known for their ability to manipulate the behaviour of their host enhancing its anti-predator defenses to avoid concomitant predation. We found that the growth rate of individual parasites in rainbow trout increased with the infrapopulation size (positive density-dependence) suggesting cost sharing. Moreover, parasites adjusted their growth to the intensity of infection within the eye lens where they were localized suggesting population density sensing. Results of this study support the hypothesis that macroparasites can adjust their growth rate and manipulation investment according to cost sharing level and infrapopulation size.

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