Summary: Artificially elevating heart rate reduces stroke volume, leading to cardiac output ‘autoregulation’; adrenergic stimulation is needed to concurrently increase myocardial contractility to maintain stroke volume and increase cardiac output.
METHODS & TECHNIQUES
An exploratory clustering approach for extracting stride parameters from tracking collars on free-ranging wild animals
Summary: An unsupervised machine learning and phase-based steady locomotion detection method allows stride parameters to be extracted from GPS/accelerometer animal tracking collar data collected from free-ranging wild animals.
The presence and role of interstitial cells of Cajal in the proximal intestine of shorthorn sculpin (Myoxocephalus scorpius)
Summary: Gastrointestinal motility patterns in shorthorn sculpin are primarily generated by the interstitial cells of Cajal (ICC).
Reversible developmental stasis in response to nutrient availability in the Xenopus laevis central nervous system
Summary: With limited nutrients, developing Xenopus laevis tadpoles enter a week-long period of reversible stasis during which animals continue to move but growth and proliferation cease until food becomes available again.
Summary: Proteasome activity in the gills of Antarctic fish demonstrated a high degree of temperature compensation, providing evidence of cold adaptation of the protein degradation machinery.
Pre-copula acoustic behaviour of males in the malarial mosquitoes Anopheles coluzzii and Anopheles gambiae s.s. does not contribute to reproductive isolation
Highlighted Article: Anopheles gambiae s.s. and A. coluzzii male mosquitoes display similar stereotypical acoustic behaviour in response to tones within the female wing-beat frequency range; assortative mating between these species is unlikely to be based on this stereotypical pre-copula acoustic behaviour.
Thermal sensitivity and phenotypic plasticity of cardiac mitochondrial metabolism in European perch, Perca fluviatilis
Summary: Impaired myocardial energy production at high temperatures may set the thermal limit of the heart in European perch, despite the phenotypic plasticity and compensatory flexibility of its enzymatic components.
Correlations of metabolic rate and body acceleration in three species of coastal sharks under contrasting temperature regimes
Summary: Calibrations between metabolic rate, body acceleration and temperature in three coastal sharks offer a tool to estimate field metabolic rates in these species.
Summary: Only ‘smart’ juvenile snails have the capability to form long-term memory; ‘average’ juvenile snails do not possess this ability.
Life on the edge: O2 binding in Atlantic cod red blood cells near their southern distribution limit is not sensitive to temperature or haemoglobin genotype
Highlighted Article: Red blood cell oxygen binding affinity in Atlantic cod near their southern, warmer limit of distribution is largely temperature independent and not affected by functional differences between their major haemoglobin genotypes.
Summary: Ammonia excretion in a common marine burrowing polychaete occurs via dentrically branched and well-vascularized branchiae, which exhibit a high abundance of three ammonia transporters and a Rhesus-like protein.
Summary: Pigeons control their pecking movements with two distinct stop phases that are dependent on stimulus size and type.
Effects of prolonged anoxia on electrical activity of the heart in crucian carp (Carassius carassius)
Summary: Low temperature pre-conditions fish heart for prolonged anoxia by changes in activity of excitation–contraction coupling genes and thereby allows sustained bradycardia and prolongation of ventricular action potential when oxygen shortage sets in.
Blood clotting behavior is innately modulated in Ursus americanus during early and late denning relative to summer months
Summary: Features of the blood clotting cascade of black bears provide novel insights into the underlying mechanisms they evoke for embolic protection during hibernation.
Highlighted Article: European hedgehogs are declining in Britain, particularly on arable land; badger presence and habitat use impact on hedgehogs’ energy expenditure, explaining hedgehog distribution in rural areas.
Intramolecular interactions that control voltage sensitivity in the jShak1 potassium channel from Polyorchis penicillatus
Summary: The voltage sensitivity of a jellyfish potassium channel is responsive to amino acid changes in disparate parts of the protein; changes in these different parts interact in complex ways.
Increasing trunk flexion transforms human leg function into that of birds despite different leg morphology
Summary: Mimicking a bird's horizontal trunk orientation leads to a bird-like leg function in humans despite different morphology of the segmented legs.
Cold acclimation improves chill tolerance in the migratory locust through preservation of ion balance and membrane potential
Summary: Chill tolerance is linked to maintenance of ion homeostasis, suggesting a link to membrane potential; this link is demonstrated as cold acclimation improved chill tolerance through preservation of membrane polarization.
Summary: Olfactory cues, critical to the behaviour and physiology of sea lamprey (Petromyzon marinus), exhibit partial overlap among lamprey species.