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The thermal phase of solar X-ray flares has been described as heating-triggered evolution of plasma confined in coronal loops. This paper describes how the modeling of the thermal phase of spatially resolved solar X-ray flares has been extended to investigate spatially unresolved stellar X-ray flares with different scopes, aims and perspectives. Hydrodynamic models are able to describe the evolution of global flare features, such as the X-ray light curves, and to put constraints on heating location. Based on the solar analogy, either detailed hydrodynamic models or approximate analytical descriptions of the decay of flaring coronal loops or loop systems have been extensively applied to infer the size of stellar flaring regions. Approximate approaches tend to overestimate the size of the flaring regions, in particular in the presence of significant heating during the decay. Such heating is consistently diagnosed and included in a model based on extensive hydrodynamic modeling of decaying loops. Applications to recent data from Chandra and XMM-Newton missions, and present and future perspectives are discussed. [Copyright &y& Elsevier]

Highlights: [•] The steady state behavior of a MGT at two different load conditions is studied. [•] Jet-A1 kerosene and blends with sunflower and rapeseed oils are tested. [•] Small percentage of SVO added to Jet-A1 slightly affects MGT emissions. [•] PM levels are independent of oil concentration in fuel blends but depend on SVO quality. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To describe morphologic and functional modifications of the ulnar nerve at the wrist in carpal tunnel syndrome (CTS) after carpal tunnel release (CTR). Methods: Ultrasonography was used to study the cross sectional area (CSA) of the ulnar nerve at Guyon’s canal, before and 1 and 6months after CTR, in 18 CTS patients. A parallel electrophysiological and clinical analysis was also conducted. Results: CSA of the ulnar nerve significantly increased 6months after CTR. Ten (55%) cases showed abnormal CSA values compared to a control group before surgery and five (28%) at 6month follow-up. In addition, there were improvements in the motor and sensory ulnar axon recruitment properties and the conduction values in sensory ulnar fibres. Patients with extra-median distribution of paresthesia (4 subjects) were free from symptoms. Conclusions: CTR has a significant effect not only on the anatomical geometry of Guyon’s canal, but also on the morphology and function of the ulnar nerve. Significance: In CTS, high pressure in the carpal tunnel may result in anatomical changes of ulnar nerve, thus causing functional impairment to the ulnar fibres. CTR appears to reverse some of this damage. [Copyright &y& Elsevier]

The Sun is the late-type star we can study with the highest level of detail. In the interpretation of stellar data, therefore, it is often assumed that the physical processes of the coronae of late-type stars are similar to those of the solar corona, i.e. the “solar-stellar analogy”. In order to investigate the validity of this assumption, we have started a program to study systematically the Sun as an X-ray star. Our program aims to explore how far the solar model can be applied to other stars. In this paper we review the results obtained from these studies and, in particular, we discuss the variability of a star identical to the Sun during its cycle, the contribution of different coronal regions to the whole corona X-ray spectrum, and the role of flares. We find that the non-flaring Sun during its cycle fits well in the stellar scenario as a low-activity star. Our results suggest that the coronae of stars from low to intermediate activity may be explained as the effect of structures similar to those present on the Sun, changing the relative weight of the different kinds of non-flaring coronal regions; the coronae of very active stars may be explained if a continuous flaring activity characterizes these stars. Possible implications in stellar data interpretation are discussed. [Copyright &y& Elsevier]

Abstract: XMM-Newton spatial/spectral resolution and high effective area allow to deepen our knowledge about the shocks in Supernova Remnants and their interaction with the interstellar medium. We present the analysis of an EPIC observation of the northern rim of the Vela SNR and we compare the X-ray and optical morphology of the emission. We derive a description of the internal structure of the shocked interstellar clouds, arguing that the transmitted shock model is compatible with our data. We also suggest that thermal conduction between clouds and inter-cloud medium is very efficient and produces the evaporation of the clouds in the interstellar medium. [Copyright &y& Elsevier]