Plasticity-led and mutation-led evolutions are different modes of the same developmental gene regulatory network
PeerJ » Biophysics
by Eden T.H. Ng, Akira R. Kinjo
3w ago
The standard theory of evolution proposes that mutations cause heritable variations, which are naturally selected, leading to evolution. However, this mutation-led evolution (MLE) is being questioned by an alternative theory called plasticity-led evolution (PLE). PLE suggests that an environmental change induces adaptive phenotypes, which are later genetically accommodated. According to PLE, developmental systems should be able to respond to environmental changes adaptively. However, developmental systems are known to be robust against environmental and mutational perturbations. Thus, we expec ..read more
Visit website
A Cellular Potts Model of the interplay of synchronization and aggregation
PeerJ » Biophysics
by Rose Una, Tilmann Glimm
1M ago
We investigate the behavior of systems of cells with intracellular molecular oscillators (“clocks”) where cell-cell adhesion is mediated by differences in clock phase between neighbors. This is motivated by phenomena in developmental biology and in aggregative multicellularity of unicellular organisms. In such systems, aggregation co-occurs with clock synchronization. To account for the effects of spatially extended cells, we use the Cellular Potts Model (CPM), a lattice agent-based model. We find four distinct possible phases: global synchronization, local synchronization, incoherence, and an ..read more
Visit website
Multiscale transport and 4D time-lapse imaging in precision-cut liver slices (PCLS)
PeerJ » Biophysics
by Iqra Azam, James D. Benson
1M ago
Background Monitoring cellular processes across different levels of complexity, from the cellular to the tissue scale, is important for understanding tissue structure and function. However, it is challenging to monitor and estimate these structural and dynamic interactions within three-dimensional (3D) tissue models. Objective The aim of this study was to design a method for imaging, tracking, and quantifying 3D changes in cell morphology (shape and size) within liver tissue, specifically a precision-cut liver slice (PCLS). A PCLS is a 3D model of the liver that allows the study of the structu ..read more
Visit website
Arthrological reconstructions of the pterosaur neck and their implications for the cervical position at rest
PeerJ » Biophysics
by Richard Buchmann, Taissa Rodrigues
2M ago
The lack of any pterosaur living descendants creates gaps in the knowledge of the biology of this group, including its cervical biomechanics, which makes it difficult to understand their posture and life habits. To mitigate part of this issue, we reconstructed the cervical osteology and arthrology of three pterosaurs, allowing us to make inferences about the position of the neck of these animals at rest. We used scans of three-dimensionally preserved cervical series of Anhanguera piscator, Azhdarcho lancicollis and Rhamphorhynchus muensteri for the reconstructions, thus representing different ..read more
Visit website
Nitrogen addition enhances seed yield by improving soil enzyme activity and nutrients
PeerJ » Biophysics
by Wenbo Mi, Feng Luo, Wenhui Liu, Yan Qin, Yongchao Zhang, Kaiqiang Liu, Wen Li
3M ago
Nitrogen (N) addition is a simple and effective field management approach to enhancing plant productivity. Nonetheless, the regulatory mechanisms governing nitrogen concentrations and their effect on soil enzyme activity, nutrient levels, and seed yield in the Festuca kirilowii seed field have yet to be elucidated. Therefore, this study sought to investigate the effect of N fertilizer application on soil enzyme activities, soil nutrients, and seed yield of F. kirilowii Steud cv. Huanhu, the only domesticated variety in the Festuca genus of the Poaceae family, was investigated based on two-year ..read more
Visit website
Carotenoid-dependent singlet oxygen photogeneration in light-harvesting complex 2 of Ectothiorhodospira haloalkaliphila leads to the formation of organic hydroperoxides and damage to both pigments and protein matrix
PeerJ » Biophysics
by Denis Yanykin, Mark Paskhin, Aleksandr Aleksandrovich Ashikhmin, Maxim Alexandrovich Bolshakov
3M ago
Earlier, it was suggested that carotenoids in light-harvesting complexes 2 (LH2) can generate singlet oxygen, further oxidizing bacteriochlorophyll to 3-acetyl-chlorophyll. In the present work, it was found that illumination of isolated LH2 preparations of purple sulfur bacterium Ectothiorhodospira haloalkaliphila with light in the carotenoid absorption region leads to the photoconsumption of molecular oxygen, which is accompanied by the formation of hydroperoxides of organic molecules in the complexes. Photoformation of two types of organic hydroperoxides were revealed: highly lipophilic (12 ..read more
Visit website
Osmotic response during kidney perfusion with cryoprotectant in isotonic or hypotonic vehicle solution
PeerJ » Biophysics
by Ross M. Warner, Jun Yang, Andrew Drake, Youngjoo Lee, Sarah Nemanic, David Scott, Adam Z. Higgins
5M 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
Visit website
Rational synthesis of total damage during cryoprotectant equilibration: modelling and experimental validation of osmomechanical, temperature, and cytotoxic damage in sea urchin (Paracentrotus lividus) oocytes
PeerJ » Biophysics
by Dominic J. Olver, Pablo Heres, Estefania Paredes, James D. Benson
8M 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
Visit website
Comparison of the elastic recovery and strain-in-compression of commercial and novel vinyl polysiloxane impression materials incorporating a novel crosslinking agent and a surfactant
PeerJ » Biophysics
by Shahab Ud Din, Osama Khattak, Farooq Ahmad Chaudhary, Asfia Saeed, Azhar Iqbal, Jamaluddin Syed, Alaa Ahmed Kensara, Thani Alsharari, Mohammed Mustafa, Sherif Elsayed Sultan, Mangala Patel
9M 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
Visit website
Micro-shear bond strength of different calcium silicate materials to bulk-fill composite
PeerJ » Biophysics
by Seda Falakaloğlu, Merve Yeniçeri Özata, Gianluca Plotino
1y 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
Visit website

Follow PeerJ » Biophysics on FeedSpot

Continue with Google
Continue with Apple
OR