Design principles of a conditional futile cycle exploited for regulation

Bees require suitably close foraging and nesting sites to minimize travel time and energy expenditure for brood provisioning. Knowing foraging distances in persistent (‘healthy’) populations is therefore crucial for assessing harmful levels of habitat fragmentation. For small bees, such distances are poorly known because of the difficulty of individual tagging and problems with mark-recapture approaches. Using apiarist’s number tags and colour codes, we marked 2689 males and females of four oligolectic and two polylectic species of Osmiini bees (Megachilidae, genera Chelostoma, Heriades, Hoplitis, Osmia) with body lengths of 6 to 15 mm. The work was carried out in 21 ha-large urban garden that harbours at least 106 species of wild bees. Based on 450 re-sightings, mean female flight distances ranged from 73 to 121 m and male distances from 59 to 100 m. These foraging distances suggest that as a rule of thumb, flower strips and nesting sites for supporting small solitary bees should be no further than 150 m apart.

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Modeling Multi-Site Computation Offloading in Unreliable Cloud Environments

10.32920/ryerson.14660922.v1 ◽

2021 ◽

Author(s):

Marzieh Ranjbar Pirbasti

Keyword(s):

Energy Consumption ◽

Response Time ◽

Mobile Device ◽

Fault Injection ◽

Computation Offloading ◽

Failure Rates ◽

Recovery Mechanisms ◽

Efficient Allocations ◽

Cloud Servers ◽

Time And Energy

Offloading heavy computations from a mobile device to cloud servers can reduce the power consumption of the mobile device and improve the response time of mobile applications. However, the gains of offloading can be significantly affected by failures of cloud servers and network links. In this thesis, we propose a fault-aware, multi-site computation offloading model capable of finding efficient allocations of tasks to resources. Our model reduces both response time and energy consumption by incorporating the effect of failures and recovery mechanisms for various offloading allocations. In addition, we create a fault-injection framework to evaluate an allocation under various failure rates and recovery mechanisms. The experiments carried out with our fault-injection framework demonstrate that our fault-aware model can determine an allocation—based on the type of failures, failure rates, and the employed recovery mechanisms—that improves both response time and lower energy consumption compared to model without failures.

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Local design principles at hippocampal synapses revealed by an energy-information trade-off

10.1101/748400 ◽

2019 ◽

Cited By ~ 1

Author(s):

Gaurang Mahajan ◽

Suhita Nadkarni

Keyword(s):

Information Transfer ◽

Design Principles ◽

Short Term ◽

Vesicle Release ◽

Efficient Manner ◽

Heterogeneous Distribution ◽

Trade Off ◽

Release Probability ◽

Wide Range ◽

Hippocampal Synapses

AbstractSynapses across different brain regions display distinct structure-function relationships. We investigate the interplay of fundamental design principles that shape the transmission properties of the excitatory CA3-CA1 pyramidal cell connection, a prototypic synapse for studying the mechanisms of learning in the hippocampus. This small synapse is characterized by probabilistic release of transmitter, which is markedly facilitated in response to naturally occurring trains of action potentials. Based on a physiologically realistic computational model of the CA3 presynaptic terminal, we show how unreliability and short-term dynamics of vesicle release work together to regulate the trade-off of information transfer versus energy use. We propose that individual CA3-CA1 synapses are designed to operate at close to maximum possible capacity of information transfer in an efficient manner. Experimental measurements reveal a wide range of vesicle release probabilities at hippocampal synapses, which may be a necessary consequence of long-term plasticity and homeostatic mechanisms that manifest as presynaptic modifications of release probability. We show that the timescales and magnitude of short-term plasticity render synaptic information transfer nearly independent of differences in release probability. Thus, individual synapses transmit optimally while maintaining a heterogeneous distribution of presynaptic strengths indicative of synaptically-encoded memory representations. Our results support the view that organizing principles that are evident on higher scales of neural organization percolate down to the design of an individual synapse.

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Not afraid to trust you: Trustworthiness moderates gaze cueing but not in highly anxious participants

10.31219/osf.io/hde55 ◽

2016 ◽

Author(s):

Felix Suessenbach ◽

Felix D. Schönbrodt

Keyword(s):

Response Time ◽

Trait Anxiety ◽

Significant Interaction ◽

Exploratory Analysis ◽

Human Interaction ◽

Trade Off ◽

Gaze Cueing ◽

Cueing Effect ◽

Negative Target ◽

Gaze Cues

Gaze Cueing (i.e.,the shifting of person B’s attention by following person A’s gaze) is closely linked with human interaction and learning. To make the most of this connection, researchers need to investigate possible moderators enhancing or reducing the extent of this attentional shifting. In this study we used a gaze cueing paradigm to demonstrate that the perceived trustworthiness of a cueing person constitutes such a moderator for female participants. Our results show a significant interaction between perceived trustworthiness and the response time trade-off between valid and invalid gaze cues (gaze cueing effect), as manifested in greater following of a person’s gaze if this person was trustworthy as opposed to the following of an untrustworthy person’s gaze. An additional exploratory analysis showed potentially moderating influences of trait-anxiety on this interaction (p= .057). The affective background of the experiment (i.e., using positive or negative target stimuli) had no influence.

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Quantitative Systems Biology to decipher design principles of a dynamic cell cycle network: the “Maximum Allowable mammalian Trade–Off–Weight” (MAmTOW)

npj Systems Biology and Applications ◽

10.1038/s41540-017-0028-x ◽

2017 ◽

Vol 3 (1) ◽

Cited By ~ 5

Author(s):

Matteo Barberis ◽

Paul Verbruggen

Keyword(s):

Cell Cycle ◽

Systems Biology ◽

Design Principles ◽

Trade Off ◽

Dynamic Cell

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Energy Invested in Reproduction by Thick-Billed Murres (Uria lomvia)

The Auk ◽

10.1093/auk/102.3.447 ◽

1985 ◽

Vol 102 (3) ◽

pp. 447-458 ◽

Cited By ~ 28

Author(s):

A. J. Gaston

Keyword(s):

Energy Expenditure ◽

Total Energy ◽

Reproductive Activity ◽

Total Energy Expenditure ◽

Energy Budgets ◽

Uria Lomvia ◽

Energy Investment ◽

Cepphus Grylle ◽

The Difference ◽

Time And Energy

Abstract Pelagic seabirds that lay single-egg clutches have been thought to invest less energy in reproduction than inshore-feeding species that rear more than one young. To examine this idea I calculated time and energy budgets for Thick-billed Murres (Uria lomvia) breeding at two large arctic colonies and compared their energy expenditure with that of a hypothetical group (shirkers) that was capable of feeding at the same rate but did not attempt any reproductive activity. The difference in energy investment between breeders and shirkers was strongly dependent on the average foraging range. I also compared my results with similar estimates for inshore-feeding Black Guillemots (Cepphus grylle). For the two Thick-billed Murre colonies, energy allocated to reproduction represented 30% and 24% of total energy expenditure during the breeding season. These values exceed the estimates for Black Guillemots. The amount of energy invested by Thick-billed Murres at the colonies considered probably is similar to that invested by other seabirds laying larger clutches and rearing heavier young.

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