Tolerance of Hyas araneus zoea I larvae to elevated seawater PCO2 despite elevated metabolic costs

Running power as measured by foot-worn sensors is considered to be associated with the metabolic cost of running. In this study, we show that running economy needs to be taken into account when deriving metabolic cost from accelerometer data. We administered an experiment in which 32 experienced participants (age = 28 ± 7 years, weekly running distance = 51 ± 24 km) ran at a constant speed with modified spatiotemporal gait characteristics (stride length, ground contact time, use of arms). We recorded both their metabolic costs of transportation, as well as running power, as measured by a Stryd sensor. Purposely varying the running style impacts the running economy and leads to significant differences in the metabolic cost of running (p < 0.01). At the same time, the expected rise in running power does not follow this change, and there is a significant difference in the relation between metabolic cost and power (p < 0.001). These results stand in contrast to the previously reported link between metabolic and mechanical running characteristics estimated by foot-worn sensors. This casts doubt on the feasibility of measuring running power in the field, as well as using it as a training signal.

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Effects of Lifting in Four Restricted Work Postures

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128703100417 ◽

1987 ◽

Vol 31 (4) ◽

pp. 462-466 ◽

Cited By ~ 1

Author(s):

Sean Gallagher ◽

Richard L. Unger ◽

E. William Rossi

Keyword(s):

Muscle Function ◽

Coal Mines ◽

Trunk Muscle ◽

Trunk Muscles ◽

Coal Miners ◽

Metabolic Costs ◽

Lifting Capacity ◽

Asymmetric Lifting

The purpose of this study was to examine the lifting capacity of low-seam coal miners in four restricted work postures (roof heights of 36″, 40″, 44″, and 48″), investigate the associated metabolic costs, and to examine electromyographic (EMG) data from eight trunk muscles during the lifting procedure. Subjects were thirteen underground miners accustomed to handling materials in restricted work postures. Each subject performed two twenty-minute periods of asymmetric lifting in each of four postures during the day of testing. The frequency of lifting was 10 lifts per minute. A specially designed lifting box incorporated microswitches in one handle of the box and another in the bottom of the box, in order to examine the trunk muscle function at specific points during the lfting cycle. The data collected will be used by the Bureau of Mines to make recommendations for lifting materials in low-seam coal mines.

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Comparisons of Growth in Weight of Temperate and Tropical Marine Fish Counterparts

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f84-169 ◽

1984 ◽

Vol 41 (9) ◽

pp. 1381-1384 ◽

Cited By ~ 6

Author(s):

R. R. C. Edwards

Keyword(s):

Marine Fish ◽

Growth Rates ◽

Metabolic Costs ◽

The Tropics

For temperate and tropical marine teleosts I compared growth in mean weight with age with similar trophic positions and ecological habits. Temperate demersal forms generally grew faster than tropical counterparts whereas mesopelagic and pelagic forms were similar. I suggest that differences in growth rates may be related to higher metabolic costs in the tropics in comparison with temperate waters.

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The Distribution of Hyas Araneus (L.) and Hyas Coarctatus Leach (Crustacea: Decapoda: Brachyura) in the North Sea and the Svalbard Region

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400060902 ◽

1985 ◽

Vol 65 (1) ◽

pp. 195-201 ◽

Cited By ~ 3

Author(s):

M. F. Dyer

Keyword(s):

Relative Density ◽

North Sea ◽

Benthic Invertebrates ◽

Distribution Patterns ◽

The North ◽

The North Sea ◽

Hyas Araneus ◽

Presence And Absence ◽

Marine Benthic Invertebrates

The distribution patterns of many marine benthic invertebrates are not well known, and when records exist they are usually in the form of presence and absence data with little or no information on the relative density of populations from area to area.

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Energy cost associated with moving platforms

PeerJ ◽

10.7717/peerj.5439 ◽

2018 ◽

Vol 6 ◽

pp. e5439 ◽

Cited By ~ 1

Author(s):

Carolyn A. Duncan ◽

Scott N. MacKinnon ◽

Jacques F. Marais ◽

Fabien A. Basset

Keyword(s):

Energy Cost ◽

Postural Stability ◽

Commercial Fishing ◽

Moving Platforms ◽

Metabolic Costs ◽

Significant Performance ◽

Operator Fatigue ◽

Exact Effect ◽

Experienced Personnel ◽

Platform Motions

BackgroundPrevious research suggests motion induced fatigue contributes to significant performance degradation and is likely related to a higher incidence of accidents and injuries. However, the exact effect of continuous multidirectional platform perturbations on energy cost (EC) with experienced personnel on boats and other seafaring vessels remains unknown.ObjectiveThe objective of this experiment was to measure the metabolic ECs associated with maintaining postural stability in a motion-rich environment.MethodsTwenty volunteer participants, who were free of any musculoskeletal or balance disorders, performed three tasks while immersed in a moving environment that varied motion profiles similar to those experienced by workers on a mid-size commercial fishing vessel (static platform (baseline), low and high motions (HMs)). Cardiorespiratory parameters were collected using an indirect calorimetric system that continuously measured breath-by-breath samples. Heart rate was recoded using a wireless heart monitor.ResultsResults indicate a systematic increase in metabolic costs associated with increased platform motions. The increases were most pronounced during the standing and lifting activities and were 50% greater during the HM condition when compared to no motion. Increased heart rates were also observed.DiscussionPlatform motions have a significant impact on metabolic costs that are both task and magnitude of motion dependent. Practitioners must take into consideration the influence of motion-rich environments upon the systematic accumulation of operator fatigue.

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Overwinter thermal habitat use in lakes by anadromous Arctic char

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0420 ◽

2018 ◽

Vol 75 (12) ◽

pp. 2343-2353 ◽

Cited By ~ 10

Author(s):

Ingeborg M. Mulder ◽

Corey J. Morris ◽

J. Brian Dempson ◽

Ian A. Fleming ◽

Michael Power

Keyword(s):

Habitat Use ◽

Water Column ◽

Prey Capture ◽

Salvelinus Alpinus ◽

Late Summer ◽

Arctic Char ◽

Foraging Efficiency ◽

Thermal Habitat ◽

Metabolic Costs ◽

Seaward Migration

Anadromous Arctic char (Salvelinus alpinus) migrate back to fresh water in late summer to spawn and (or) overwinter. Upon freshwater entry, feeding is reduced or absent, and movement activity is restricted. While the physiological responses to low temperatures (e.g., growth, metabolism) are understood, specifics of the use of thermal habitat for overwintering remains poorly characterized. This study used acoustic and archival telemetry data from two lakes in southern Labrador, Canada, to study thermal habitat use during the ice-covered period. Results showed that lake-dwelling anadromous Arctic char predominantly occupied a narrow range of temperatures (0.5–2 °C) and used cooler temperatures available within the middle and upper water column. Use of the selected temperatures is likely a strategy that lowers metabolic costs and minimizes energy expenditure, preserving stored lipids for overwinter survival and the energetic costs of preparation for seaward migration. As Arctic char are visual feeders, use of the upper water column is also thought to aid foraging efficiency by increasing the likelihood of prey capture.

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