Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

CdZnTe Radiation Detectors with HgTe/HgCdTe Superlattice Contacts for Leakage Current Reduction

CdZnTe-based heterojunctionp-i-n or M-π-n detectors using HgTe/CdTe superlattice contacts are modeled and designed to reduce leakage currents under high electric fields and thereby improve X-ray and γ-ray detector performance. The employment of an n-type HgTe/CdTe superlattice as a contact layer can theoretically result in significantly less leakage current compared to a contact layer using either bulk semiconductors or metal contacts. The benefits arise from the ability to design HgTe/CdTesuperlattices to have large carrier effective masses in the electric field direction, which results in low carrier velocities. Nevertheless the density of states is lower than that of a comparable bulk semiconductor, which results in low carrier concentrations