Poly(propylene fumarate) (PPF) has shown potential for the treatment of bone defects as it can be 3D printed into scaffolds to suit patient-specific needs with strength comparable to that of bone. However, the lack of specific cell attachment and osteogenic signaling moieties have limited their utility as it is necessary to provide these signals to aid in bone tissue formation. To address this issue and provide a platform for functionalization, Bioglass (∼1−2 μm) microparticles have been incorporated into PPF to create a 3D printable resin with concentrations ranging from 0 to 10 wt %. The zero-shear viscosity of PPF-Bioglass resins increased proportionally from 0 to 2.5 wt % Bioglass, with values of 0.22 and 0.34 Pa•s, respectively. At higher Bioglass concentrations, 5 and 10 wt %, the resin viscosity increased to 0.44 and 1.31 Pa•s, exhibiting a 2-and 6-fold increase from the 0 wt % Bioglass resin. Despite this increase in viscosity, all resins remained printable with no print failures. In addition, the surface available Bioglass can tether catechol containing molecules for postprinting functionalization. Analysis of PPF-Bioglass functionalization using a catechol dye analyte shows functionalization increases with Bioglass concentration, up to 157 nmol/ cm 2 , and demonstrates it is possible to modulate functionalization. This presents a versatile and highly translationally relevant strategy to functionalize 3D printed scaffolds post printing with a diverse array of functional species.

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Tarsipes rostratus is a 5-15 g marsupial with a natural distribution restricted to shrublands and heathlands of southwestern Australia. In the laboratory, it has metabolic rates that vary from 150-350 J (g.h)-1, and does not become torpid if artificial nectar is available. When nectar is removed, animals ultimately become torpid for intervals of several hours, during which metabolic rates are often reduced by more than 90%. The time taken by animals to become torpid is reduced, and the duration of torpor bouts increased, if body size and ambient temperature are decreased. By becoming torpid under the experimental conditions imposed, animals reduce their total daily energy expenditures by approximately 70%. It is suggested that torpor occurs when the energy reserves of animals fall below a critical level. In the field, torpor is most prevalent in animals the weight less than 7 g, and occurs predominantly during the period from March to September. Evidence relating to possible causes of torpor in the field is equivocal.