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Nitrogen (N) recycling is a key mechanism to ensure the sustainability of miscanthus production with no or small fertiliser inputs, but little is known on the subject in miscanthus species other than the most cultivated Miscanthus × giganteus. This field experiment on Miscanthus × giganteus and Miscanthus sinensis quantified plant biomass and N stock dynamics during two years. Endogenous net N fluxes, calculated from the evolution of plant N content throughout time, were higher in Miscanthus × giganteus than in Miscanthus sinensis. Indeed, 79 kg N ha−1 and 105 to 197 kg N ha−1 were remobilised during spring and autumn, respectively, for Miscanthus × giganteus, as opposed to 13 to 25 kg N ha−1 and 46 to 128 kg N ha−1 for Miscanthus sinensis. However, N recycling efficiency, defined as the ratio between N remobilisation fluxes and the maximum above-ground N content, did not differ significantly between the two species. N recycling efficiency ranged from 8 to 27% for spring remobilisation and from 63 to 74% and 24 to 38% for autumn remobilisation calculated on above-ground and below-ground N, respectively. Exogenous N, the main source of N to constitute maximum plant N content for all genotypes, was provided by fertilisation (22 to 24%) and organic matter mineralisation or other sources (43 to 59%). During winter, 42 to 56% of plant N content was lost. Only a small part of these plant N losses was due to abscised leaves (6–12% of the maximum plant N content). Our results show that Miscanthus sinensis is as efficient as Miscanthus × giganteus in N recycling and N use efficiency and as performant as other perennial species. [ABSTRACT FROM AUTHOR]

The purpose of the study was to evaluate the CT abnormalities of airways and lung parenchyma in asthmatic patients and to assess inter- and intraobserver variability for these abnormalities. The CT scans of 50 asthmatic patients and 10 healthy volunteers were assessed independently by four independent chest radiologists who were masked with respect to the clinical information. Bronchiectasis involving mostly subsegmental and distal bronchi was noted in 28.5% of the asthmatic subjects and none of the non-asthmatics. Bronchial wall thickening, small centrilobular opacities and decreased lung attenuation were observed in 82%, 21% and 31% of asthmatic patients respectively, compared with 7%, 5% and 7% of healthy subjects. The intra- and inter-observer agreements for these four CT abnormalities were measured by the kappa statistic and ranged from 0.60 to 0.79 and from 0.40 to 0.64, respectively. It is concluded that asthmatic patients may exhibit bronchial wall thickening, bronchiectasis and morphological abnormalities suggestive of distal airways disease that can be assessed on CT scans with a clinically acceptable observer variability. [ABSTRACT FROM AUTHOR]

Posttransplant lymphoproliferative disorders (PTLD), developing after immunosuppressive therapy in human organ-graft recipients, are, for the most part, Epstein-Barr virus-induced. The earlier the diagnosis is made, the greater the potential for reversibility. The chest radiographs and CT scans of 10 patients with thoracic locations of PTLD were reviewed. Mediastinal ( n = 3) and hilar adenopathy ( n = 2), pulmonary nodules ( n = 8), and pleural thickening or effusion ( n = 4) were encountered. The incidence of partial resolution with clinical remission ( n = 4) appears to be noteworthy, and in all likelihood is related to the extensive necrosis ( n = 5) that is frequently seen. Slow regression, transitory deterioration in one case, and localization only on the graft side in two cases, were observed. These morphological and evolutionary peculiarities must be known in order to optimize the diagnosis, and thus the prognosis, of these very original disorders. [ABSTRACT FROM AUTHOR]

A case of a right cervical aortic arch associated with a subaortic left brachiocephalic vein is reported. CT and MRI findings were correlated to the angiogram. The mechanism responsible for the coexistence of these two abnormalities is discussed. [ABSTRACT FROM AUTHOR]