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Summary Background In the wake of the SARS-CoV-2 pandemic and unprecedented global demand, clinicians are struggling to source adequate access to personal protective equipment. Respirators can be in short supply, though are necessary to protect workers from SARS-CoV-2 exposure. Rapid decontamination and reuse of respirators may provide relief for the strained procurement situation. Method In this study, we investigated the suitability of 70°C dry heat and microwave-generated steam (MGS) for reprocessing of FFP2/N95-type respirators, and Type-II surgical face masks. Staphylococcus aureus was used as a surrogate as it is less susceptible than enveloped viruses to chemical and physical processes. Results We observed >4 log10 reductions in the viability of dry S. aureus treated by dry heat for 90 min at 70°C and >6 log10 reductions by MGS for 90 s. After 3 reprocessing cycles, neither process was found to negatively impact the bacterial or NaCl filtration efficiency of the respirators that were tested. However, MGS was incompatible with Type-II surgical masks tested, as we confirmed that bacterial filtration capacity was completely lost following reprocessing. MGS was observed to be incompatible with some respirator types due to arcing observed around some types of metal nose clips and by loss of adhesion of clips to the mask. Conclusion Considering the advantages and disadvantages of each approach, we propose a reprocessing personal protective equipment/face mask workflow for use in medical areas.

Incidence rates of a third head of biceps brachii muscle have been shown to vary based on race, sex, and side of the body. Traditionally, males were thought to have higher incidences than females, and the right limb was thought to most frequently contain an additional head of biceps brachii. Additionally, innervation of this third head has been unclear, with musculocutaneous nerve, median nerve, or a combination of both providing nerve supply. Here we present findings of the dissection of 23 cadavers (n = 46 limbs), in which 6 limbs demonstrated a third head of biceps brachii. Of the 6 limbs with a third head, 3 were left and 3 were right limbs, with one cadaver having the extra muscle head bilaterally. Incidence rates in females in the current study were observed to be higher than expected (20.8%), while males showed a 4.5% occurrence. All 6 of the additional heads of biceps brachii observed were innervated by musculocutaneous nerve. Together these data show a higher than expected number of female cadavers with a third head of biceps brachii, equal incidence between sides of the body, and uniform innervation by musculocutaneous nerve. These findings challenge our traditional understanding of the third head of biceps brachii and suggests a need for additional study of this complex anatomical variation. Keywords: Biceps brachii, Third head, Innervation, Sex, Cadaver, Variation