Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) procedure for colorectal liver metastasis

Since first described, Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) has garnered boisterous praise and fervent criticism. Its rapid adoption and employment for a variety of indications resulted in high perioperative morbidity and mortality. However recent risk stratification, refinement of technique to reduce the impact of stage I and progression along the learning curve have resulted in improved outcomes. The first randomized trial comparing ALPPS to two stage hepatectomy (TSH) for colorectal liver metastases (CRLM) was recently published demonstrating comparable perioperative morbidity and mortality with improved resectability and survival following ALPPS. In this review, as ALPPS enters the thirteenth year since conception, the current status of this contentious two stage technique is presented and best practices for deployment in the treatment of CRLM is codified

Dynamics of the Earth's particle radiation environment

The physical processes affecting the dynamics of the Earth's particle radiation environment are reviewed along with scientific and engineering models developed for its description. The emphasis is on models that are either operational engineering models or models presently under development for this purpose. Three components of the radiation environment, i.e., galactic cosmic rays (GCRs), solar energetic particles (SEPs) and trapped radiation, are considered separately. In the case of SEP models, we make a distinction between statistical flux/fluence models and those aimed at forecasting events. Models of the effects of particle radiation on the atmosphere are also reviewed. Further, we summarize the main features of the models and discuss the main outstanding issues concerning the models and their possible use in operational space weather forecasting. We emphasize the need for continuing the development of physics-based models of the Earth's particle radiation environment, and their validation with observational data, until the models are ready to be used for nowcasting and/or forecasting the dynamics of the environment

Acceleration and Propagation of Solar Energetic Particles

Solar Energetic Particles (SEPs) are an important component of Space Weather, including radiation hazard to humans and electronic equipment, and the ionisation of the Earth’s atmosphere. We review the key observations of SEPs, our current understanding of their acceleration and transport, and discuss how this knowledge is incorporated within Space Weather forecasting tools. Mechanisms for acceleration during solar flares and at shocks driven by Coronal Mass Ejections (CMEs) are discussed, as well as the timing relationships between signatures of solar eruptive events and the detection of SEPs in interplanetary space. Evidence on how the parameters of SEP events are related to those of the parent solar activity is reviewed and transport effects influencing SEP propagation to near-Earth locations are examined. Finally, the approaches to forecasting Space Weather SEP effects are discussed. We conclude that both flare and CME shock acceleration contribute to Space Weather relevant SEP populations and need to be considered within forecasting tools