
PeerJ » Biophysics
6 FOLLOWERS
This Biophysics Overlay is a subset of the peer-reviewed articles and rapid preprints found in PeerJ and PeerJ Preprints, respectively. PeerJ has seven peer-reviewed, open access, scholarly journals: "PeerJ" which publishes articles in biology, environmental science, medicine, and health, and "PeerJ Computer Science" serving the computer science community. The mission is to..
PeerJ » Biophysics
1w ago
Organ cryopreservation would revolutionize transplantation by overcoming the shelf-life limitations of conventional organ storage. To prepare an organ for cryopreservation, it is first perfused with cryoprotectants (CPAs). These chemicals can enable vitrification during cooling, preventing ice damage. However, CPAs can also cause toxicity and osmotic damage. It is a major challenge to find the optimal balance between protecting the cells from ice and avoiding CPA-induced damage. In this study, we examined the organ perfusion process to shed light on phenomena relevant to cryopreservation proto ..read more
PeerJ » Biophysics
3M ago
Sea urchins (e.g., Paracentrotus lividus) are important for both aquaculture and as model species. Despite their importance, biobanking of urchin oocytes by cryopreservation is currently not possible. Optimized cryoprotectant loading may enable novel vitrification methods and thus successful cryopreservation of oocytes. One method for determining an optimized loading protocol uses membrane characteristics and models of damage, namely osmomechanical damage, temperature damage (e.g., chill injury) and cytotoxicity. Here we present and experimentally evaluate existing and novel models of these da ..read more
PeerJ » Biophysics
4M ago
This study aims to formulate experimental vinylpolysiloxane (VPS) impression materials and compare their elastic recovery and strain-in-compressions with three commercial VPS materials (Aquasil, Elite, and Extrude). Five experimental materials (Exp), two hydrophobic (Exp-I and II) and three hydrophilic (Exp-III, IV and V) were developed. Exp 1 contained vinyl-terminated poly-dimethyl siloxane and a conventional cross-linking agent (poly methylhydrosiloxane), while Exp- II contained a novel cross-linking agent that is tetra-functional dimethyl-silyl-ortho-silicate (TFDMSOS). Exp III–V (hydrophi ..read more
PeerJ » Biophysics
8M ago
Introduction
This study aimed to compare the micro-shear bond strength (µSBS) performances of two resin-based calcium silicate-based cement (CSC) (TheraCal PT and TheraCal LC), Biodentine, and two modified-MTA CSC materials (NeoMTA 2 and BioMTA+) to bulk-fill restorative material.
Materials and Methods
Fifty 3D printed cylindrical resin blocks with a central hole were used (2 mm in depth and 4 mm in diameter). CSCs were placed in the holes (per each group n = 10) and incubated for 24 h. Cylindrical polyethylene molds (2 mm in height and diameter) were used to place the bulk-fill restorative ma ..read more
PeerJ » Biophysics
9M ago
Background
Physical exercise is a source of stress to the human body, triggering different ventilatory responses through different regulatory mechanisms and the aquatic environment imposes several restrictions to the swimmer, particularly regarding the restricted ventilation. Thus, we aimed to assess the acute ventilatory responses and to characterize the adopted breathing patterns when swimming front crawl at increasing intensity domains.
Methods
Eighteen well-trained swimmers performed 7 × 200 m front crawl (0.05 m∙s−1 velocity increments) and a maximal 100 m (30 s rest intervals). Pulmonary ..read more
PeerJ » Biophysics
11M ago
Background
During counter movement jumps, adding weight in the eccentric phase and then suddenly releasing this weight during the concentric phase, known as accentuated eccentric loading (AEL), has been suggested to immediately improve jumping performance. The level of evidence for the positive effects of AEL remains weak, with conflicting evidence over the effectiveness in enhancing performance. Therefore, we proposed to theoretically explore the influence of implementing AEL during constrained vertical jumping using computer modelling and simulation and examined whether the proposed mechanis ..read more
PeerJ » Biophysics
11M ago
In human walking, power for propulsion is generated primarily via ankle and hip muscles. The addition of a ‘passive’ hip spring to simple bipedal models appears more efficient than using only push-off impulse, at least, when hip spring associated energetic costs are not considered. Hip flexion and retraction torques, however, are not ‘free’, as they are produced by muscles demanding metabolic energy. Studies evaluating the inclusion of hip actuation costs, especially during the swing phase, and the hip actuation’s energetic benefits are few and far between. It is also unknown whether these pos ..read more
PeerJ » Biophysics
1y ago
Protein aggregation in the form of amyloid fibrils is linked with the onset and progression of more than 30 amyloidoses, including multiple neurodegenerative disorders, such as Alzheimer’s or Parkinson’s disease. Despite countless studies and years of research, the process of such aggregate formation is still not fully understood. One peculiar aspect of amyloids is that they appear to be capable of undergoing structural rearrangements even after the fibrils have already formed. Such a phenomenon was reported to occur in the case of alpha-synuclein and amyloid beta aggregates after a long perio ..read more
PeerJ » Biophysics
1y ago
I present a Bayesian phylogenetic predictive modelling (PPM) framework that allows the prediction of muscle parameters (physiological cross-sectional area, APhys) in extinct archosaurs from skull width (WSk) and phylogeny. This approach is robust to phylogenetic uncertainty and highly versatile given its ability to base predictions on simple, readily available predictor variables. The PPM presented here has high prediction accuracy (up to 95%), with downstream biomechanical modelling yielding bite force estimates that are in line with previous estimates based on muscle parameters from reconstr ..read more
PeerJ » Biophysics
1y ago
Introduction
Aerobic exercise interventions may affect different cognitive domains such as attention, working memory, inhibition, etc. However, the neural mechanisms underlying this relationship, remains uncertain.
Objective
To perform a systematic review on exercise intervention studies that use event-related potentials (ERPs) as outcome for cognitive performance.
Methods
We identified studies through searches in four databases reporting the effects of either an acute bout or chronic exercise on any ERP associated with cognitive performance. Study population included participants >17 years ..read more