An optimum estimator of body size to relate to behavioural and physiological parameters in field studies

2005 ◽  
Vol 38 (3) ◽  
pp. 159-168 ◽  
Author(s):  
Rogelio Macias-Ordonez ◽  
Matt Draud
Keyword(s):  
Body Size ◽  
Field Studies ◽  
Physiological Parameters ◽  
Optimum Estimator

Field studies of ammonia excretion in Aphanius iberus (Pisces; Cyprinodontidae): body size and habitat effects

2007 ◽  
Vol 23 (1) ◽  
pp. 93-98 ◽  
Author(s):  
F. J. Oliva-Paterna ◽  
J. García-Alonso ◽  
V. Cardozo ◽  
M. Torralva
Keyword(s):  
Body Size ◽  
Ammonia Excretion ◽  
Field Studies

scholarly journals Fresh-Water Mollusks as Biomonitors for Ecotoxicity of Nanomaterials

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 944
Author(s):  
Natalia Abramenko ◽  
Petr Mashkin ◽  
Sergey Volkov ◽  
Vladimir Olshanskiy ◽  
Leonid Kustov
Keyword(s):  
Fresh Water ◽  
Aquatic Environment ◽  
Field Studies ◽  
Physiological Parameters ◽  
Toxic Effects ◽  
Neural Systems ◽  
Unio Tumidus

The use of different nanoparticles (NPs) is growing every year since discoveries of their unique properties. The wide use of nanomaterials has raised concerns about their safety and possible accumulation in the aquatic environment. Mussels are being considered as one of the most suitable organisms for bioaccumulation monitoring. Within our study, we focused on developing the method that can be applied in field studies of ecotoxicity and can be nondestructive and informative at early times of exposure, while at the same time being based on changes of physiological parameters of fresh water mussels. The changes in the cardiovascular and neural systems of mollusks (Anodonta anatina and Unio tumidus) were measured as biomarkers of toxic effects. Different monometallic and bimetallic NPs, silicon NPs with various ligands were applied as test substances. Changes in cardiovascular and neural functions were in good correlation with accumulation tests for all tested NPs.

scholarly journals Effect of Spatial Disorientation in a Virtual Environment on Gait and Vital Features in Patients with Dementia: Pilot Single-Blind Randomized Control Trial

10.2196/18455 ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. e18455
Author(s):  
Chimezie O Amaefule ◽  
Stefan Lüdtke ◽  
Thomas Kirste ◽  
Stefan J Teipel
Keyword(s):  
Older People ◽  
Real World ◽  
Perceived Control ◽  
Field Studies ◽  
Physiological Parameters ◽  
Large Variability ◽  
Spatial Disorientation ◽  
People With Dementia ◽  
Physiological Markers ◽  
Task Systems

Background Orientation deficits are among the most devastating consequences of early dementia. Digital navigation devices could overcome these deficits if adaptable to the user’s needs (ie, provide situation-aware, proactive navigation assistance). To fulfill this task, systems need to automatically detect spatial disorientation from sensors in real time. Ideally, this would require field studies consisting of real-world navigation. However, such field studies can be challenging and are not guaranteed to cover sufficient instances of disorientation due to the large variability of real-world settings and a lack of control over the environment. Objective Extending a foregoing field study, we aim to evaluate the feasibility of using a sophisticated virtual reality (VR) setup, which allows a more controlled observation of disorientation states and accompanying behavioral and physiological parameters in cognitively healthy older people and people with dementia. Methods In this feasibility study, we described the experimental design and pilot outcomes of an ongoing study aimed at investigating the effect of disorientation on gait and selected physiological features in a virtual laboratory. We transferred a real-world navigation task to a treadmill-based virtual system for gait analysis. Disorientation was induced by deliberately manipulating landmarks in the VR projection. Associated responses in motion behavior and physiological parameters were recorded by sensors. Primary outcomes were variations in motion and physiological parameters, frequency of disorientation, and questionnaire-derived usability estimates (immersion and perceived control of the gait system) for our population of interest. At this time, the included participants were 9 cognitively healthy older participants [5/9 women, 4/9 men; mean age 70 years, SD 4.40; Mini–Mental State Examination (MMSE) mean 29, SD 0.70) and 4 participants with dementia (2/4 women, 2/4 men; mean age 78 years, SD 2.30 years; MMSE mean 20.50, SD 7.54). Recruitment is ongoing, with the aim of including 30 cognitively healthy older participants and 20 participants with dementia. Results All 13 participants completed the experiment. Patients’ route was adapted by shortening it relative to the original route. Average instances of disorientation were 21.40, 36.50, and 37.50 for the cognitively healthy older control, cognitively healthy older experimental participants, and participants with dementia, respectively. Questionnaire outcomes indicated that participants experienced adequate usability and immersion; 4.30 for presence, 3.73 for involvement, and 3.85 for realism of 7 possible points, indicating a good overall ability to cope with the experiment. Variations were also observed in motion and physiological parameters during instances of disorientation. Conclusions This study presents the first feasibility outcomes of a study investigating the viability of using a sophisticated VR setup, based on an earlier real-world navigation study, to study spatial disorientation among cognitively healthy older people and people with dementia. Preliminary outcomes give confidence to the notion that our setup can be used to assess motion and physiological markers of disorientation, even in people with cognitive decline. Trial Registration ClinicalTrials.gov; https://clinicaltrials.gov/ct2/show/NCT04134806

scholarly journals Effect of Spatial Disorientation in a Virtual Environment on Gait and Vital Features in Patients with Dementia: Pilot Single-Blind Randomized Control Trial (Preprint)

2020 ◽  
Author(s):  
Chimezie O Amaefule ◽  
Stefan Lüdtke ◽  
Thomas Kirste ◽  
Stefan J Teipel
Keyword(s):  
Older People ◽  
Real World ◽  
Perceived Control ◽  
Field Studies ◽  
Physiological Parameters ◽  
Large Variability ◽  
Spatial Disorientation ◽  
People With Dementia ◽  
Physiological Markers ◽  
Task Systems

BACKGROUND Orientation deficits are among the most devastating consequences of early dementia. Digital navigation devices could overcome these deficits if adaptable to the user’s needs (ie, provide situation-aware, proactive navigation assistance). To fulfill this task, systems need to automatically detect spatial disorientation from sensors in real time. Ideally, this would require field studies consisting of real-world navigation. However, such field studies can be challenging and are not guaranteed to cover sufficient instances of disorientation due to the large variability of real-world settings and a lack of control over the environment. OBJECTIVE Extending a foregoing field study, we aim to evaluate the feasibility of using a sophisticated virtual reality (VR) setup, which allows a more controlled observation of disorientation states and accompanying behavioral and physiological parameters in cognitively healthy older people and people with dementia. METHODS In this feasibility study, we described the experimental design and pilot outcomes of an ongoing study aimed at investigating the effect of disorientation on gait and selected physiological features in a virtual laboratory. We transferred a real-world navigation task to a treadmill-based virtual system for gait analysis. Disorientation was induced by deliberately manipulating landmarks in the VR projection. Associated responses in motion behavior and physiological parameters were recorded by sensors. Primary outcomes were variations in motion and physiological parameters, frequency of disorientation, and questionnaire-derived usability estimates (immersion and perceived control of the gait system) for our population of interest. At this time, the included participants were 9 cognitively healthy older participants [5/9 women, 4/9 men; mean age 70 years, SD 4.40; Mini–Mental State Examination (MMSE) mean 29, SD 0.70) and 4 participants with dementia (2/4 women, 2/4 men; mean age 78 years, SD 2.30 years; MMSE mean 20.50, SD 7.54). Recruitment is ongoing, with the aim of including 30 cognitively healthy older participants and 20 participants with dementia. RESULTS All 13 participants completed the experiment. Patients’ route was adapted by shortening it relative to the original route. Average instances of disorientation were 21.40, 36.50, and 37.50 for the cognitively healthy older control, cognitively healthy older experimental participants, and participants with dementia, respectively. Questionnaire outcomes indicated that participants experienced adequate usability and immersion; 4.30 for presence, 3.73 for involvement, and 3.85 for realism of 7 possible points, indicating a good overall ability to cope with the experiment. Variations were also observed in motion and physiological parameters during instances of disorientation. CONCLUSIONS This study presents the first feasibility outcomes of a study investigating the viability of using a sophisticated VR setup, based on an earlier real-world navigation study, to study spatial disorientation among cognitively healthy older people and people with dementia. Preliminary outcomes give confidence to the notion that our setup can be used to assess motion and physiological markers of disorientation, even in people with cognitive decline. CLINICALTRIAL ClinicalTrials.gov; https://clinicaltrials.gov/ct2/show/NCT04134806

scholarly journals Energetic underpinnings of yellow dung fly mating success in the field

2021 ◽  
Vol 5 ◽  
pp. 61-67
Author(s):  
Wolf U. Blanckenhorn
Keyword(s):  
Body Size ◽  
Mating Success ◽  
Time Budget ◽  
Field Studies ◽  
Cow Dung ◽  
Time Budgets ◽  
Animal Reproduction ◽  
Scathophaga Stercoraria ◽  
Foraging Time ◽  
Small Insect

Foraging provides the basis for animal reproduction, but requires energy and time to be sustained, entailing a trade-off. Whereas females should maximize their time foraging for resources, males should minimize their foraging time by optimizing time budgets to maximize their access to mating partners. Mark-resight field studies are difficult and hence uncommon for small insects. Yellow dung flies (Scathophaga stercoraria L.) abound on pastures in cold-temperate regions across the northern hemisphere. Adult flies lick nectar from flowers for energy, but require small insect prey to produce eggs and sperm. Males wait for females around fresh cow dung, but at one point also need to replenish their energy and/or sperm reserves in the surrounding vegetation. Their foraging time budgets should depend on their body size, nutritional energy reserves, availability of sperm, competitor and female density. Marked male dung flies whose nutritional status was experimentally manipulated – water only (null control); water + sugar (energy replenishment); or water, sugar + Drosophila prey (energy and sperm replenishment) – were repeatedly observed on an experimental pasture for an entire day. Both nutrient types were expected to increase the mating success of especially large males. The total number of resighted males seen copulating was lowest for water-treated flies. Mating success was positively related to body size. The distance travelled between dung pats was greater for males fed sugar or prey and also increased with body size, while pat residence times decreased with size. No differences were found between the sugar- and prey-fed groups. Crucially however, there was no evidence in the field for a time budget or mating advantage of small males when nutrients were limited.

Body size - realized fecundity relationship of whitemarked tussock moth

2003 ◽  
Vol 135 (4) ◽  
pp. 583-586 ◽  
Author(s):  
Graham S. Thurston ◽  
James D. MacGregor
Keyword(s):  
Body Size ◽  
Egg Production ◽  
Laboratory Experiments ◽  
Field Studies ◽  
Main Body ◽  
Extrinsic Factors ◽  
Potential Fecundity ◽  
Abiotic Conditions ◽  
Relationship Of ◽  
Whitemarked Tussock Moth

Insect body size and fecundity are frequently reported to be correlated (e.g., Miller 1957; Dempster 1971; Beckwith 1976; Hough and Pimental 1978; Gilbert 1984; Carroll and Quiring 1993; Honek 1993; Spurgeon et al. 1995; Tammaru et al. 1996, 2002; Nylin and Gotthard 1998). The main body of evidence for this relationship stems from laboratory experiments where potential fecundity (or total egg production) is most often measured (Tammaru et al. 1996); very little evidence is available from field studies (Sopow and Quiring 1998). Realized fecundity (or total eggs laid) is affected by many extrinsic factors (e.g., Leather 1988; Carroll and Quiring 1993; Tammaru et al. 1996), suggesting that fecundity measures derived from laboratory experimentation may not be useful in nature where abiotic conditions may be highly variable (Carroll and Quiring 1993; Nylin and Gotthard 1998; Sopow and Quiring 1998).

First-Person Experiments in Thinking

2018 ◽  
Vol 23 (3) ◽  
pp. 189-205 ◽  
Author(s):  
Renatus Ziegler ◽  
Ulrich Weger
Keyword(s):  
Physiological Parameters ◽  
The Self ◽  
First Person ◽  
Psychological Phenomena ◽  
Third Person ◽  
Current Article ◽  
Thinking Process ◽  
Mental Contents

Abstract. In psychology, thinking is typically studied in terms of a range of behavioral or physiological parameters, focusing, for instance, on the mental contents or the neuronal correlates of the thinking process proper. In the current article, by contrast, we seek to complement this approach with an exploration into the experiential or inner dimensions of thinking. These are subtle and elusive and hence easily escape a mode of inquiry that focuses on externally measurable outcomes. We illustrate how a sufficiently trained introspective approach can become a radar for facets of thinking that have found hardly any recognition in the literature so far. We consider this an important complement to third-person research because these introspective observations not only allow for new insights into the nature of thinking proper but also cast other psychological phenomena in a new light, for instance, attention and the self. We outline and discuss our findings and also present a roadmap for the reader interested in studying these phenomena in detail.

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