Additional value of EUS in oesophageal cancer patients staged N0 on PET/CT: validation of a prognostic model

Background Lymph node metastases are a major prognostic indicator in oesophageal cancer. Radiological staging largely influences treatment decisions and is becoming more reliant on PET and CT. However, the sensitivity of these modalities is suboptimal and is known to under-stage disease. The primary aim of this study was to validate a published prognostic model in oesophageal cancer patients staged N0 with PET/CT, which showed that EUS nodal status was an independent predictor of survival. The secondary aim was to assess the prognostic significance of pathological lymph node metastases in this cohort. Methods An independent validation cohort included 139 consecutive patients from a regional upper gastrointestinal cancer network staged N0 with PET/CT between 1st January 2013 and 31st June 2015. Replicating the original study, two Cox regression models were produced: one included EUS T-stage and EUS N-stage, and one included EUS T-stage and EUS N0 versus N+. The primary outcome of the prognostic model was overall survival (OS). Kaplan–Meier analysis assessed differences in OS between pathological node-negative (pN0) and node-positive (pN+) groups. A p value of < 0.05 was considered statistically significant. Results The mean OS of the validation cohort was 29.8 months (95% CI 27.1–35.2). EUS T-stage was significantly and independently associated with OS in both models (p = 0.011 and p = 0.012, respectively). EUS N-stage and EUS N0 versus N+ were not significantly associated with OS (p = 0.553 and p = 0.359, respectively). There was a significant difference in OS between pN0 and pN+ groups (χ2 13.315, df 1, p < 0.001). Conclusion Lymph node metastases have a significant detrimental effect on OS. This validation study did not replicate the results of the developed prognostic model but the continued benefit of EUS in patients staged N0 with PET/CT was demonstrated. EUS remains a valuable component of a multi-modality approach to oesophageal cancer staging

A systems analysis of the erythropoietic responses to weightlessness. Volume 1: Mathematical model simulations of the erythropoietic responses to weightlessness

Theoretical responses to weightlessness are summarized. The studies include development and validation of a model of erythropoiesis regulation, analysis of the behavior of erythropoiesis under a variety of conditions, simulations of bed rest and space flight, and an evaluation of ground-based animal studies which were conducted as analogs of zero-g. A review of all relevant space flight findings and a set of testable hypotheses which attempt to explain how red cell mass decreases in space flight are presented. An additional document describes details of the mathematical model used in these studies

Can snow depth be used to predict the distribution of the high Arctic aphid Acyrthosiphon svalbardicum (Hemiptera: Aphididae) on Spitsbergen?

<p>Abstract</p> <p>Background</p> <p>The Svalbard endemic aphid <it>Acyrthosiphon svalbardicum </it>(Heikinheimo, 1968) is host specific to <it>Dryas octopetala </it>L. ssp <it>octopetala </it>(Rosaceae). It has been hypothesized that the aphid is present on those areas with a thin winter snow cover and which therefore clear of snow earlier in the season. This early snow clearance results in a longer growing period and allows the aphid to experience at least the minimum number of degree days required to complete its life cycle. However, this hypothesis lacked a detailed field validation. We aimed to test the relationship between the aphid distribution and time of snow clearance at landscape scale, mapping snow depth at peak of snow accumulation for the two succeeding years 2009 and 2010 and examining site occupancy and plant phenology the following summers. Additionally, the distribution range mapped by Strathdee & Bale (1995) was revisited to address possible changes in range along the coast of the fjord.</p> <p>Results</p> <p>A linear relation between snow depth and timing of snow melt was found but with strong inter-annual and landscape variation. Both snow depth and plant phenology were found to affect patch occupancy. In August, the aphid, at the three life stages scored (viviparae, oviparae/males and eggs), was present most frequently in those <it>D. octopetala </it>patches with the most advanced plant phenology and which showed shallower snow depths in spring. However, many patches predicted to contain aphids were empty. The aphid distribution range has expanded 4.7 km towards the fjord mouth from 1995.</p> <p>Conclusions</p> <p>Snow depth alone, and hence date of snow clearance, cannot precisely define species distribution at landscape scale, as this cannot explain why are they unoccupied patches under shallow snow depths with advanced plant phenology. We nonetheless present a model Arctic system that could form the basis for long term monitoring for climate- driven species shifts.</p

Collaborative digital and wide format printing: Methods and considerations for the artist and master printer

This thesis investigates the collaborative production of fine art digital prints for artists,a process which is used by many contemporary practitioners including RichardHamilton and Damien Hirst. Digital print as a fine art process has emerged over the last twenty years, and as yet, there is no in depth evidence on the collaborative endeavour and production process which is central to the digital Master Printer’s role.The investigation first establishes the historical context and significance of the Master and Printer in traditional printmaking, and the more recent development of the digital print studio and the digital print pioneers of the 1990s. A series of seven artists’ case studies in the context of the collaborative digital print studio are then offered to demonstrate the working process. The analysis of these proposes a best practice model for Master Printers working with contemporary artists to produce high quality, fine art, wide format inkjet digital prints.The study also compares production methods at the cutting-edge digital facility of the Rijksakademie in The Netherlands, to assess the validity of the practices proposed through a facility closest to the study’s research base at the CFPR’s digital studio. The comparative study also explored the expanding digital production process and the role of the Master Printer. Evolving production processes are also considered in this study as a response to the advancement of digital print technology alongside a practical exploration of what actually constitutes a digital print in this rapidly expanding field of fine art printmaking.This study aims to reveal the inner workings of the digital collaborative process between the artist and Master Printer, and appraise the digital Master Printer’s role.It offers a set of best practice methods for the digital Master Printer developed from this research. The study also considers how the digital print, and the digital print studio may evolve in line with current and future developments in new technologies

Biotechnology

Biotechnological problems of man machine systems required for long duration space flight

Readiness for First Crewed Flight

The NASA Engineering and Safety Center (NESC) was requested to develop a generic framework for evaluating whether any given program has sufficiently complete and balanced plans in place to allow crewmembers to fly safely on a human spaceflight system for the first time (i.e., first crewed flight). The NESC assembled a small team which included experts with experience developing robotic and human spaceflight and aviation systems through first crewed test flight and into operational capability. The NESC team conducted a historical review of the steps leading up to the first crewed flights of Mercury through the Space Shuttle. Benchmarking was also conducted with the United States (U.S.) Air Force and U.S. Navy. This report contains documentation of that review