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Cortical bone mapping: An application to hand and foot bones in hominoids
Bone form reflects both the genetic profile and behavioural history of an individual. As cortical bone is able to remodel in response to mechanical stimuli, interspecific differences in cortical bone thickness may relate to loading during locomotion or manual behaviours during object manipulation. Here, we test the application of a novel method of cortical bone mapping to the third metacarpal (Mc3) and talus of Pan, Pongo, and Homo. This method of analysis allows measurement of cortical thickness throughout the bone, and as such is applicable to elements with complex morphology. In addition, it allows for registration of each specimen to a canonical surface, and identifies regions where cortical thickness differs significantly between groups. Cortical bone mapping has potential for application to palaeoanthropological studies; however, due to the complexity of correctly registering homologous regions across varied morphology, further methodological development would be advantageous
Core temperature responses to cold-water immersion recovery: A pooled-data analysis
© 2018 Human Kinetics, Inc. Purpose: To examine the effect of postexercise cold-water immersion (CWI) protocols, compared with control (CON), on the magnitude and time course of core temperature (Tc) responses. Methods: Pooled-data analyses were used to examine the Tc responses of 157 subjects from previous postexercise CWI trials in the authors’ laboratories. CWI protocols varied with different combinations of temperature, duration, immersion depth, and mode (continuous vs intermittent). Tc was examined as a double difference (ΔΔTc), calculated as the change in Tc in CWI condition minus the corresponding change in CON. The effect of CWI on ΔΔTc was assessed using separate linear mixed models across 2 time components (component 1, immersion; component 2, postintervention). Results: Intermittent CWI resulted in a mean decrease in ΔΔTc that was 0.25°C (0.10°C) (estimate [SE]) greater than continuous CWI during the immersion component (P = .02). There was a significant effect of CWI temperature during the immersion component (P = .05), where reductions in water temperature of 1°C resulted in decreases in ΔΔTc of 0.03°C (0.01°C). Similarly, the effect of CWI duration was significant during the immersion component (P = .01), where every 1 min of immersion resulted in a decrease in ΔΔTc of 0.02°C (0.01°C). The peak difference in Tc between the CWI and CON interventions during the postimmersion component occurred at 60 min postintervention. Conclusions: Variations in CWI mode, duration, and temperature may have a significant effect on the extent of change in Tc. Careful consideration should be given to determine the optimal amount of core cooling before deciding which combination of protocol factors to prescribe
Some remarks on PM2.5
Since 1970, the General Physics Department of «Università degli Studi di Torino» has carried out a project research, on inorganic solid particulate matter. The special issue of Annals of Geophysics, published for Professor Giorgio Fiocco’s 70th birthday, gives us the possibility to make some important remarks on this topic, focusing on PM2.5. This has been possible using all the old and new experimental data of the measures made by the authors of this paper since 1970
Dimensionality and dynamics in the behavior of C. elegans
A major challenge in analyzing animal behavior is to discover some underlying
simplicity in complex motor actions. Here we show that the space of shapes
adopted by the nematode C. elegans is surprisingly low dimensional, with just
four dimensions accounting for 95% of the shape variance, and we partially
reconstruct "equations of motion" for the dynamics in this space. These
dynamics have multiple attractors, and we find that the worm visits these in a
rapid and almost completely deterministic response to weak thermal stimuli.
Stimulus-dependent correlations among the different modes suggest that one can
generate more reliable behaviors by synchronizing stimuli to the state of the
worm in shape space. We confirm this prediction, effectively "steering" the
worm in real time.Comment: 9 pages, 6 figures, minor correction
Using interpretative phenomenological analysis to inform physiotherapy practice: An introduction with reference to the lived experience of cerebellar ataxia
The attached file is a pre-published version of the full and final paper which can be found at the link below.This article has been made available through the Brunel Open Access Publishing Fund.Qualitative research methods that focus on the lived experience of people with health conditions are relatively
underutilised in physiotherapy research. This article aims to introduce interpretative phenomenological analysis
(IPA), a research methodology oriented toward exploring and understanding the experience of a particular
phenomenon (e.g., living with spinal cord injury or chronic pain, or being the carer of someone with a particular
health condition). Researchers using IPA try to find out how people make sense of their experiences and the
meanings they attach to them. The findings from IPA research are highly nuanced and offer a fine grained
understanding that can be used to contextualise existing quantitative research, to inform understanding of novel
or underresearched topics or, in their own right, to provoke a reappraisal of what is considered known about
a specified phenomenon. We advocate IPA as a useful and accessible approach to qualitative research that
can be used in the clinical setting to inform physiotherapy practice and the development of services from the
perspective of individuals with particular health conditions.This article is available through the Brunel Open Access Publishing Fund
Single Gene Deletions of Orexin, Leptin, Neuropeptide Y, and Ghrelin Do Not Appreciably Alter Food Anticipatory Activity in Mice
Timing activity to match resource availability is a widely conserved ability in nature. Scheduled feeding of a limited amount of food induces increased activity prior to feeding time in animals as diverse as fish and rodents. Typically, food anticipatory activity (FAA) involves temporally restricting unlimited food access (RF) to several
hours in the middle of the light cycle, which is a time of day when rodents are not normally active. We compared this model to calorie restriction (CR), giving the mice 60% of their normal daily calorie intake at the same time each day. Measurement of body temperature and home cage behaviors suggests that the RF and CR models are very similar but CR has the advantage of a clearly defined food intake and more stable mean body temperature. Using the CR model, we then attempted to verify the published result that orexin deletion diminishes food anticipatory activity (FAA) but observed little to no diminution in the response to CR and, surprisingly, that orexin KO mice are refractory to body weight loss on a CR diet. Next we tested the orexigenic neuropeptide Y (NPY) and ghrelin and the anorexigenic hormone, leptin, using mouse mutants. NPY deletion did not alter the behavior or physiological response to CR. Leptin deletion impaired FAA in terms of some activity measures, such as walking and rearing, but did not substantially diminish hanging behavior preceding feeding time, suggesting that leptin knockout mice do anticipate daily meal time but do not manifest the full spectrum of activities that typify FAA. Ghrelin knockout mice do not have impaired FAA on a CR diet. Collectively, these results suggest that the individual hormones and neuropepetides tested do not regulate FAA by acting individually but this does not rule out the possibility of their concerted action in mediating FAA
Lineage Divergence and Historical Gene Flow in the Chinese Horseshoe Bat (Rhinolophus sinicus)
PMCID: PMC3581519This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Defects in muscarinic receptor-coupled signal transduction in isolated parotid gland cells after in vivo irradiation: evidence for a non-DNA target of radiation
Radiation-induced dysfunction of normal tissue, an unwanted side effect of radiotherapeutic treatment of cancer, is usually considered to be caused by impaired loss of cell renewal due to sterilisation of stem cells. This implies that the onset of normal tissue damage is usually determined by tissue turnover rate. Salivary glands are a clear exception to this rule: they have slow turnover rates (>60 days), yet develop radiation-induced dysfunction within hours to days. We showed that this could not be explained by a hypersensitivity to radiation-induced apoptosis or necrosis of the differentiated cells. In fact, salivary cells are still capable of amylase secretion shortly after irradiation while at the same time water secretion seems specifically and severely impaired. Here, we demonstrate that salivary gland cells isolated after in vivo irradiation are impaired in their ability to mobilise calcium from intracellular stores (Ca2+i), the driving force for water secretion, after exposure to muscarinic acetylcholine receptor agonists. Using radioligand-receptor-binding assays it is shown that radiation caused no changes in receptor density, receptor affinity nor in receptor-G-protein coupling. However, muscarinic acetylcholine agonist-induced activation of protein kinase C alpha (PKCα), measured as translocation to the plasma membrane, was severely affected in irradiated cells. Also, the phorbol ester PMA could no longer induce PKCα translocation in irradiated cells. Our data hence indicate that irradiation specifically interferes with PKCα association with membranes, leading to impairment of intracellular signalling. To the best of our knowledge, these data for the first time suggest that, the cells' capacity to respond to a receptor agonist is impaired after irradiation
How Landscape Heterogeneity Frames Optimal Diffusivity in Searching Processes
Theoretical and empirical investigations of search strategies typically have failed to distinguish the distinct roles played by density versus patchiness of resources. It is well known that motility and diffusivity of organisms often increase in environments with low density of resources, but thus far there has been little progress in understanding the specific role of landscape heterogeneity and disorder on random, non-oriented motility. Here we address the general question of how the landscape heterogeneity affects the efficiency of encounter interactions under global constant density of scarce resources. We unveil the key mechanism coupling the landscape structure with optimal search diffusivity. In particular, our main result leads to an empirically testable prediction: enhanced diffusivity (including superdiffusive searches), with shift in the diffusion exponent, favors the success of target encounters in heterogeneous landscapes
Food Searching Strategy of Amoeboid Cells by Starvation Induced Run Length Extension
Food searching strategies of animals are key to their success in heterogeneous environments. The optimal search strategy may include specialized random walks such as Levy walks with heavy power-law tail distributions, or persistent walks with preferred movement in a similar direction. We have investigated the movement of the soil amoebae Dictyostelium searching for food. Dictyostelium cells move by extending pseudopodia, either in the direction of the previous pseudopod (persistent step) or in a different direction (turn). The analysis of ∼4000 pseudopodia reveals that step and turn pseudopodia are drawn from a probability distribution that is determined by cGMP/PLA2 signaling pathways. Starvation activates these pathways thereby suppressing turns and inducing steps. As a consequence, starved cells make very long nearly straight runs and disperse over ∼30-fold larger areas, without extending more or larger pseudopodia than vegetative cells. This ‘win-stay/lose-shift’ strategy for food searching is called Starvation Induced Run-length Extension. The SIRE walk explains very well the observed differences in search behavior between fed and starving organisms such as bumble-bees, flower bug, hoverfly and zooplankton
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