ABSTRACT
WHAT IS KNOWN AND OBJECTIVE: Vaccines and other pharmaceuticals are essential medical supplies that require continuous storage at specific temperatures to maintain viability. Power outages can lead to a break in the cold chain, resulting in the degradation of essential medicines. COMMENT: After a power outage, the stability of vaccines and other medicines can be difficult to ascertain. Many public health guidelines therefore recommend discarding potentially compromised pharmaceuticals unless the cold chain can be guaranteed-a costly endeavour. There are government guidelines aimed at minimizing exposure to high temperatures in the event of a power outage; however, the usefulness of these guidelines is uncertain. WHAT IS NEW AND CONCLUSION: The actual cost of vaccine and pharmaceutical loss due to a break in the cold chain is poorly studied and requires further research. Additional recommendations regarding the stability of specific medicines would also be a valuable resource.
Subject(s)
Drug Storage/standards , Electric Power Supplies/standards , Pharmaceutical Preparations/standards , Refrigeration/standards , Temperature , Vaccines/standardsABSTRACT
This work presents an overview of a series of increasingly complex oxides synthesized from CrO 2, under high-pressure and high-temperature conditions, having Cr (4+) in octahedral coordination. Although the emphasis is on the structure and microstructure of the compounds as obtained from X-ray diffraction and transmission electron microscopy and diffraction, attention is also given to their interesting electronic and magnetic properties. The study is complemented with an electron energy loss spectroscopic analysis of the different phases. These are the cubic perovskite SrCrO 3, the orthorhombic perovskite CaCrO 3, the solid solution Sr 1-xCa xCrO 3, the Ruddlesden-Popper-type Sr 3Cr 2O 7, the family CrSr 2RECu 2O 8 (RE = rare earth), a compositionally modulated perovskite "PbCrO 3", and the misfit layer oxide SrO 2[CrO 2] 1.85.
