Electrical Conductivity of Additively Manufactured Copper and Silver for Electrical Winding Applications.

Efficient and power-dense electrical machines are critical in driving the next generation of green energy technologies for many industries including automotive, aerospace and energy. However, one of the primary requirements to enable this is the fabrication of compact custom windings with optimised materials and geometries. Electrical machine windings rely on highly electrically conductive materials, and therefore, the Additive Manufacturing (AM) of custom copper (Cu) and silver (Ag) windings offers opportunities to simultaneously improve efficiency through optimised materials, custom geometries and topology and thermal management through integrated cooling strategies. Laser Powder Bed Fusion (L-PBF) is the most mature AM technology for metals, however, laser processing highly reflective and conductive metals such as Cu and Ag is highly challenging due to insufficient energy absorption. In this regard, this study details the 400 W L-PBF processing of high-purity Cu, Ag and Cu-Ag alloys and the resultant electrical conductivity performance. Six Cu and Ag material variants are investigated in four comparative studies characterising the influence of material composition, powder recoating, laser exposure and electropolishing. The highest density and electrical conductivity achieved was 88% and 73% IACS, respectively. To aid in the application of electrical insulation coatings, electropolishing parameters are established to improve surface roughness. Finally, proof-of-concept electrical machine coils are fabricated, highlighting the potential for 400 W L-PBF processing of Cu and Ag, extending the current state of the art.

Adult diphtheria in Malaysia: A case report.

In November 2016, a 28-year-old Malay man presented to the emergency department in respiratory distress, with a history of fever and sore throat. A clinical diagnosis of acute diphtheria was made and the patient was isolated and ventilated in the intensive care unit, and received diphtheria antitoxin and intravenous antibiotics. Initial laboratory findings failed to confirm diphtheria, leading to discontinuation of antibiotics and quarantine. Public health measures were reinstated after a reference laboratory cultured Corynebacterium diphtheriae. Although there was no contact with ill persons, investigation revealed incomplete immunisation history, and injection of high dose steroids prior to onset of symptoms.

Fell off of a horse--journey from Emergency Department to Stroke clinic.

The authors present a case of a young woman who presented with transient episodes of left-sided weakness after she fell off a horse. She attended Emergency Department twice before being referred to the Stroke clinic, where she was diagnosed with carotid artery dissection.