[Physical activity and pulmonary rehabilitation]

INTRODUCTION

Physical activity in daily life (PA) in patients with chronic respiratory disease is reduced. Inactivity is associated with an increased risk of hospitalisation and mortality. Even though pulmonary rehabilitation (PR) is associated with improved quality of life (fewer symptoms, greater exercise capacity…), its benefits with regard to PA remain unclear.

STATE OF THE ART

For each patient, it is important during a respiratory rehabilitation (RR) programme to evaluate PA and its determinants. Only programs aimed at improved self-management and including educational therapy (ETP) have shown a short-term increase of PA following PR. Several studies have reported better long-term adherence when professionals help the patient to construct a personalised PA project, with regular follow-up and an array of activities (local facilities, urban walking…) chosen by the patient and adapted to the environment.

PERSPECTIVES

The ongoing SARS-CoV2 pandemic has highlighted the importance of human interaction, even at a distance using information and communication technologies, as a means of sustaining patient motivation. Future controlled and randomized studies should focus on the long-term impact on PA of innovative strategies in patients with chronic respiratory diseases. Moreover, it would be interesting to quantify the socioeconomic impact as well as the sustainable health benefits of the different strategies outlined in this review.

CONCLUSION

It is not possible to offer a single solution likely to maintain RR benefits over an extended lapse of time. However, follow-up with an ETP and/or regular and customized support during the post-training period facilitates the long-term adoption of active behavior.

Spectroscopic XPEEM of highly conductive SI-doped GaN wires

Using soft X-ray photoelectron emission microscopy (XPEEM), complemented by scanning Auger microscopy (SAM) and scanning capacitance microscopy, we have quantitatively studied the incorporation of silicon and band bending at the surface (m-facet) of an individual, highly conductive Si-doped GaN micro-wires (Tchoulfian et al., Applied Physics Letters 102 (12), 2013). Electrically active n-dopants Si atoms in Ga interstitial sites are detected as nitride bonding states in the high-resolution Si2p core level spectra, and represent only a small fraction (<10%) of the overall Si surface concentration measured by SAM. The derived carrier concentration of 2×10(21) at cm(-3) is in reasonable agreement with electrical measurements. A consistent surface band bending of ~1 eV is directly evidenced by surface photo-voltage measurements. Such an approach combining different surface-sensitive microscopies is of interest for studying other heavily doped semiconducting wires.

[Pituitary metastasis revealing a lung cancer]

INTRODUCTION

Pituitary metastases are rare and difficult to diagnose. Their optimal approach and management remains to be defined.

CASE REPORT

We report the case of a 56-year-old patient suffering from squamous cell lung carcinoma who developed pituitary metastasis with secondary hypopituitarism, the symptoms of which were initially attributed to depression.

CONCLUSION

Pituitary metastases can be difficult to diagnose, which may lead to delays in care, which can be fatal.

Direct imaging of p-n junction in core-shell GaN wires

While core-shell wire-based devices offer a promising path toward improved optoelectronic applications, their development is hampered by the present uncertainty about essential semiconductor properties along the three-dimensional (3D) buried p-n junction. Thanks to a cross-sectional approach, scanning electron beam probing techniques were employed here to obtain a nanoscale spatially resolved analysis of GaN core-shell wire p-n junctions grown by catalyst-free metal-organic vapor phase epitaxy on GaN and Si substrates. Both electron beam induced current (EBIC) and secondary electron voltage constrast (VC) were demonstrated to delineate the radial and axial junction existing in the 3D structure. The Mg dopant activation process in p-GaN shell was dynamically controlled by the ebeam exposure conditions and visualized thanks to EBIC mapping. EBIC measurements were shown to yield local minority carrier/exciton diffusion lengths on the p-side (∼57 nm) and the n-side (∼15 nm) as well as depletion width in the range 40-50 nm. Under reverse bias conditions, VC imaging provided electrostatic potential maps in the vicinity of the 3D junction from which acceptor Na and donor Nd doping levels were locally determined to be Na = 3 × 10(18) cm(-3) and Nd = 3.5 × 10(18) cm(-3) in both the axial and the radial junction. Results from EBIC and VC are in good agreement. This nanoscale approach provides essential guidance to the further development of core-shell wire devices.