Feasibility of a Hybrid Risk-Adapted Monitoring System in Investigator-Sponsored Trials in Cancer.

Background: We assessed the feasibility of a hybrid monitoring system (minimal on-site monitoring + strategic central monitoring) used at the academic research office at Asan Medical Center (Seoul, Korea) in monitoring investigator-sponsored oncology trials.

Methods: Monitoring findings in three oncology trials conducted between 2014 and 2017 were compared. A confirmatory source data verification (SDV) was carried out in the low-risk trial and compared with the central monitoring findings.

Triggered reversible phase transformation between layered and spinel structure in manganese-based layered compounds.

Irreversible phase transformation of layered structure into spinel structure is considered detrimental for most of the layered structure cathode materials. Here we report that this presumably irreversible phase transformation can be rendered to be reversible in sodium birnessite (NaMnO·yHO) as a basic structural unit. This layered structure contains crystal water, which facilitates the formation of a metastable spinel-like phase and the unusual reversal back to layered structure.

Revisiting Solid Electrolyte Interphase on the Carbonaceous Electrodes Using Soft X-ray Absorption Spectroscopy.

It is widely accepted that solid electrolyte interphase (SEI) layer of carbonaceous material is formed by irreversible decomposition reaction of an electrolyte, and acts as a passivation layer to prevent further decomposition of the electrolyte, ensuring reliable operation of a Li-ion battery. On the other hand, recent studies have reported that some transition metal oxide anode materials undergo reversible decomposition of an organic electrolyte during cycling, which is completely different from carbonaceous anode materials. In this work, we revisit the electrochemical reaction of an electrolyte that produces SEI layer on the surface of carbonaceous anode materials using soft X-ray absorption spectroscopy.

Probing the Additional Capacity and Reaction Mechanism of the RuO2 Anode in Lithium Rechargeable Batteries.

The structural changes and electrochemical behavior of RuO2 are investigated by using in situ XRD, X-ray absorption spectroscopy, and electrochemical techniques to understand the electrochemical reaction mechanism of this metal oxide anode material. Intermediate phase-assisted transformation of RuO2 to LiRuO2 takes place at the start of discharge. Upon further lithiation, LiRuO2 formed by intercalation decomposes to nanosized Ru metal and Li2 O by a conversion reaction.

Lithium-ion transport through a tailored disordered phase on the LiNi0.5 Mn1.5 O4 surface for high-power cathode materials.

The phase control of spinel LiNi0.5 Mn1.5 O4 was achieved through surface treatment that led to an enhancement of its electrochemical properties.