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We present a genome assembly from an individual male Sciurus carolinensis (the eastern grey squirrel; Vertebrata; Mammalia; Eutheria; Rodentia; Sciuridae). The genome sequence is 2.82 gigabases in span. The majority of the assembly (92.3%) is scaffolded into 21 chromosomal-level scaffolds, with both X and Y sex chromosomes assembled.

We present a genome assembly from an individual male Sciurus vulgaris (the Eurasian red squirrel; Vertebrata; Mammalia; Eutheria; Rodentia; Sciuridae). The genome sequence is 2.88 gigabases in span. The majority of the assembly is scaffolded into 21 chromosomal-level scaffolds, with both X and Y sex chromosomes assembled.

An end-user response survey and assessments of inter-rater reliability before and after training.

An end-user response survey and assessments of inter-rater reliability before and after training.

In this study, the low velocity impact properties of rotationally moulded skin-foam-skin sandwich structures were investigated experimentally since there is a need for a greater understanding of the impact behaviour of these composites in service to extend the range of their applications. Polyethylene rotationally moulded sandwich structures were manufactured at various skin and core layer thickness combinations and tested using an instrumented low velocity drop weight impact testing machine at 20J to 100J impact energy levels, at room temperature. This allowed the identification of the impact response, failure mode, the effects of the skin and core layer thickness on impact resistance. Force-deflection curves, maximum force, contact time, maximum deflection versus impact energy curves were analysed. Samples were seen to fail due to the indentation dart piercing the upper and lower skins, with crushing and consolidation seen in the core foamed layer. Delamination at the core/skin interface was not observed. It was found that fracture initiates from the lower skin and then continues to grow to the upper skin via the foamed core layer. The impact resistance was noted to increase with increasing skin and core layer thickness, though an increase in skin layer thickness had a greater contribution than an increase in the core layer thickness. Keywords: Rotational moulding, skin-foam-skin, sandwich, low velocity impact, PE.

In this work, the fracture toughness of rotationally moulded Polyethylene (PE) and Polypropylene (PP) was measured using J integral methods at static loading rates and at room temperature. Two different commercially available rotational moulding grades PE and PP were tested in this study which have been used in various rotationally moulded products such as small leisure craft, water storage tanks etc. Scanning Electron Microscope (SEM), Optical Microscope, Differential Scanning Calorimetry (DSC), Solid-state Nuclear Magnetic Resonance (solid-state NMR) and X-ray scattering were used to investigate the microstructure, fracture surfaces and compare toughness properties of these materials. In PE, higher molecular weight and broader molecular weight distribution, larger amorphous and crystal region thicknesses are found to be related to higher toughness values. High molecular weight favours higher number of entanglements that improve fracture energy and broader distribution increases long chain branching of higher molecular weight fractions which creates higher entanglements at the branch sites. Larger amorphous regions promote micro-voiding more easily compared to thinner amorphous regions, leading to greater plastic deformation and energy absorption. Higher crystal thickness also contributes to micro-voiding in the amorphous region. For PP, greater plastic deformation observed in the fracture surfaces is related to higher fracture toughness values.