scholarly journals Complexity and diversity of motion amplification and control strategies in motile carnivorous plant traps

2021 ◽  
Vol 288 (1951) ◽  
pp. 20210771
Author(s):  
Ulrike Bauer ◽  
Ulrike K. Müller ◽  
Simon Poppinga
Keyword(s):  
Prey Capture ◽  
Control Strategies ◽  
Movement Control ◽  
Carnivorous Plant ◽  
Ecological Context ◽  
Plant Groups ◽  
Power And Control ◽  
Suction Traps ◽  
And Control ◽  
Mix And Match

Similar to animals, plants have evolved mechanisms for elastic energy storage and release to power and control rapid motion, yet both groups have been largely studied in isolation. This is exacerbated by the lack of consistent terminology and conceptual frameworks describing elastically powered motion in both groups. Iconic examples of fast movements can be found in carnivorous plants, which have become important models to study biomechanics, developmental processes, evolution and ecology. Trapping structures and processes vary considerably between different carnivorous plant groups. Using snap traps, suction traps and springboard-pitfall traps as examples, we illustrate how traps mix and match various mechanisms to power, trigger and actuate motions that contribute to prey capture, retention and digestion. We highlight a fundamental trade-off between energetic investment and movement control and discuss it in a functional-ecological context.

scholarly journals Hawkmoths use wingstroke-to-wingstroke frequency modulation for aerial recovery to vortex ring perturbations

2020 ◽  
Author(s):  
Jeff Gau ◽  
Ryan Gemilere ◽  
James Lynch ◽  
Nick Gravish ◽  
Simon Sponberg ◽  
...  
Keyword(s):  
Frequency Modulation ◽  
High Speed ◽  
Insect Flight ◽  
Control Strategies ◽  
Flapping Wing ◽  
Wingbeat Frequency ◽  
Mechanical Constraints ◽  
Power And Control ◽  
Long Time ◽  
And Control

AbstractCentimeter-scale fliers that combine wings with springy elements must contend with the high power requirements and mechanical constraints of flapping wing flight. Insects utilize elastic energy exchange to reduce the inertial costs of flapping wing flight and potentially match wingbeat frequencies to a mechanical resonance. Flying at resonance may be energetically favorable under steady conditions, but it is difficult to modulate the frequency of a resonant system. Evidence suggests that insects utilize frequency modulation over long time scales to adjust aerodynamic forces, but it remains an open question the extent to which insects can modulate frequency on the wingstroke-to-wingstroke timescale. If wingbeat frequencies deviate from resonance, the musculature must work against the elastic flight system, thereby potentially increasing energetic costs. To assess how insects address the simultaneous needs for power and control, we tested the capacity for wingstroke-to-wingstroke wingbeat frequency modulation by perturbing free hovering Manduca sexta with vortex rings while recording high-speed video at 2000 fps. Because hawkmoth flight muscles are synchronous, there is at least the potential for the nervous system to modulate frequency on each wingstroke. We observed ± 16% wingbeat frequency modulation in just a few wing strokes. Via instantaneous phase analysis of wing kinematics, we found that over 85% of perturbation responses required active changes in motor input frequency. Unlike their robotic counterparts that explicitly abdicate frequency modulation in favor of energy efficiency, we find that wingstroke-to-wingstroke frequency modulation is an underappreciated control strategies that complements other strategies for maneuverability and stability in insect flight.

Effective infection prevention and control strategies in a large accredited psychiatric facility in Singapore

2020 ◽  
Author(s):  
Daniel Poremski ◽  
Sandra Henrietta Subner ◽  
Grace Lam Fong Kin ◽  
Raveen Dev Ram Dev ◽  
Mok Yee Ming ◽  
...  
Keyword(s):  
Mental Health ◽  
Prevention And Control ◽  
Infection Prevention ◽  
Control Strategies ◽  
Infection Prevention And Control ◽  
Psychiatric Facility ◽  
Essential Services ◽  
Community Transmission ◽  
And Control

The Institute of Mental Health in Singapore continues to attempt to prevent the introduction of COVID-19, despite community transmission. Essential services are maintained and quarantine measures are currently unnecessary. To help similar organizations, strategies are listed along three themes: sustaining essential services, preventing infection, and managing human and consumable resources.

Power and control: transferring energy when there is work to be done

2005 ◽  
pp. 29-30
Author(s):  
Naveen Sharma ◽  
William Stanley
Keyword(s):  
Power And Control ◽  
And Control

Optimization and Control Petroleum Refinery Wastewater Treatment Systems — Status, Trends and Needs

1989 ◽  
Vol 24 (3) ◽  
pp. 463-477
Author(s):  
Stephen G. Nutt
Keyword(s):  
Wastewater Treatment ◽  
Process Control ◽  
Petroleum Refinery ◽  
Control Strategies ◽  
Refinery Wastewater ◽  
Statistical Process ◽  
Petroleum Refinery Wastewater ◽  
Optimization And Control ◽  
And Control ◽  
Wastewater Treatment Systems

Abstract Based on discussions in workshop sessions, several recurring themes became evident with respect to the optimization and control of petroleum refinery wastewater treatment systems to achieve effective removal of toxic contaminants. It was apparent that statistical process control (SPC) techniques are finding more widespread use and have been found to be effective. However, the implementation of real-time process control strategies in petroleum refinery wastewater treatment systems is in its infancy. Considerable effort will need to be expended to demonstrate the practicality of on-line sensors, and the utility of automated process control in petroleum refinery wastewater treatment systems. This paper provides a summary of the discussions held at the workshop.

International Human Rights Law and Blockade

2018 ◽  
Author(s):  
Phillip Drew
Keyword(s):  
Human Rights ◽  
International Human Rights Law ◽  
Humanitarian Law ◽  
Human Rights Law ◽  
International Human Rights ◽  
European Court ◽  
Power And Control ◽  
International Human ◽  
Extraterritorial Jurisdiction ◽  
And Control

The years since the beginning of the twenty-first century have seen a significant incursion of international human rights law into the domain that had previously been the within the exclusive purview of international humanitarian law. The expansion of extraterritorial jurisdiction, particularly by the European Court of Human Rights, means that for many states, the exercise of physical power and control over an individual outside their territory may engage the jurisdiction of human rights obligations. Understanding the expansive tendencies of certain human rights tribunals, and the apparent disdain they have for any ambiguity respecting human rights, it is offered that the uncertain nature of the law surrounding humanitarian relief during blockades could leave blockading forces vulnerable to legal challenge under human rights legislation, particularly in cases in which starvation occurs as a result of a blockade.

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