Solar Ultraviolet Bursts

The term “ultraviolet (UV) burst” is introduced to describe small, intense, transient brightenings in ultraviolet images of solar active regions. We inventorize their properties and provide a definition based on image sequences in transition-region lines. Coronal signatures are rare, and most bursts are associated with small-scale, canceling opposite-polarity fields in the photosphere that occur in emerging flux regions, moving magnetic features in sunspot moats, and sunspot light bridges. We also compare UV bursts with similar transition-region phenomena found previously in solar ultraviolet spectrometry and with similar phenomena at optical wavelengths, in particular Ellerman bombs. Akin to the latter, UV bursts are probably small-scale magnetic reconnection events occurring in the low atmosphere, at photospheric and/or chromospheric heights. Their intense emission in lines with optically thin formation gives unique diagnostic opportunities for studying the physics of magnetic reconnection in the low solar atmosphere. This paper is a review report from an International Space Science Institute team that met in 2016–2017

Screening for distant metastases in patients with ipsilateral breast tumor recurrence: the impact of different imaging modalities on distant recurrence-free interval

Purpose In patients with ipsilateral breast tumor recurrence (IBTR), the detection of distant disease determines whether the intention of the treatment is curative or palliative. Therefore, adequate preoperative staging is imperative for optimal treatment planning. The aim of this study is to evaluate the impact of conventional imaging techniques, including chest X-ray and/or CT thorax-(abdomen), liver ultrasonography(US), and skeletal scintigraphy, on the distant recurrence-free interval (DRFI) in patients with IBTR, and to compare conventional imaging with 18F-FDG PET-CT or no imaging at all. Methods This study was exclusively based on the information available at time of diagnoses of IBTR. To adjust for differences in baseline characteristics between the three imaging groups, a propensity score (PS) weighted method was used. Results Of the 495 patients included in the study, 229 (46.3%) were staged with conventional imaging, 89 patients (19.8%) were staged with 18F-FDG PET-CT, and in 168 of the patients (33.9%) no imaging was used (N=168). After a follow-up of approximately 5 years, 14.5% of all patients developed a distant recurrence as frst event after IBTR. After adjusting for the PS weights, the Cox regression analyses showed that the diferent staging methods had no signifcant impact on the DRFI. Conclusions This study showed a wide variation in the use of imaging modalities for staging IBTR patients in the Netherlands. After using PS weighting, no statistically signifcant impact of the diferent imaging modalities on DRFI was shown. Based on these results, it is not possible to recommend staging for distant metastases using 18F-FDG PET-CT over conventional imaging technique

Reference models for advanced e-services

Reference models (RMs) capitalize on the experience that key functions and relationships determine a system’s main design structure which has to be established before other design details can be settled. As such RMs can play an important role in designing complex (distributed) systems, in allocating design tasks to cooperating design teams and in facilitating their communication. These roles are also eminent in standardization. This paper discusses the need for precisely defined basic architectural concepts to construct RMs, building on experience with designing the OSI-RM. We apply these concepts in the design of a number of RMs for networked applications that provide advanced eservices