SUMMARY Basal thyroid function was assessed from the serum thyroxine, triiodothyronine, and thyroid-stimulating hormone concentrations in 1 14 patients (mean age 13 * 6 years), designated group 1, with thalassaemia major. Forty of these patients were further evaluated (group 2) for serum-free thyroxine, and free and reverse triiodothyronine concentrations. The response of thyroid-stimulating hormone to thyrotrophin-releasing hormone was measured in 25 patients from this subgroup. Results were compared with those from 53 control subjects. Primary hypothyroidism, defined by a raised thyroid-stimulating hormone level above the upper range limit of 6 5 VdU/ml of the controls, was present in 17 5 % of the 114 patients. In group 2 patients, a spectrum of thyroid disease spanning uncompensated and compensated primary hypothyroidism and decreased thyroid reserve was evident. The presence of primary hypothyroidism (uncompensated and compensated) was associated with an age of at least 10 years, an increased incidence of iron toxicity-related systemic complications, and an increased transfusion iron load, but not with an increased serum ferritin level. In the total 114 patients there were 9 who had the low triiodothyronine (sick euthyroid) syndrome. Primary hypothyroidism occurs in a significant proportion of thalassaemia major patients in the absence of obvious clinical signs of hypothyroidism; the low triiodothyronine syndrome associated with non-thyroidal disease is not uncommon.

In today's technology-assisted society, social interactions may be expressed through a variety of techno-communication channels, including online social networks, email and mobile phones (calls, text messages). Consequently, a clear grasp of human behavior through the diverse communication media is considered a key factor in understanding the formation of the today's information society. So far, all previous research on user communication behavior has focused on a sole communication activity. In this paper we move forward another step on this research path by performing a multidimensional study of human sociality as an expression of the use of mobile phones. The paper focuses on user temporal communication behavior in the interplay between the two complementary communication media, text messages and phone calls, that represent the bi-dimensional scenario of analysis. Our study provides a theoretical framework for analyzing multidimensional bursts as the most general burst category, that includes one-dimensional bursts as the simplest case, and offers empirical evidence of their nature by following the combined phone call/text message communication patterns of approximately one million people over three-month period. This quantitative approach enables the design of a generative model rooted in the three most significant features of the multidimensional burst - the number of dimensions, prevalence and interleaving degree - able to reproduce the main media usage attitude. The other findings of the paper include a novel multidimensional burst detection algorithm and an insight analysis of the human media selection process.

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We introduce a technique for reachability analysis of Time-Basic (TB) Petri nets, a powerful formalism for realtime systems where time constraints are expressed as intervals, representing possible transition firing times, whose bounds are functions of marking's time description. The technique consists of building a symbolic reachability graph relying on a sort of time coverage, and overcomes the limitations of the only available analyzer for TB nets, based in turn on a time-bounded inspection of a (possibly infinite) reachability-tree. The graph construction algorithm has been automated by a tool-set, briefly described in the paper together with its main functionality and analysis capability. A running example is used throughout the paper to sketch the symbolic graph construction. A use case describing a small real system -that the running example is an excerpt from -has been employed to benchmark the technique and the tool-set. The main outcome of this test are also presented in the paper. Ongoing work, in the perspective of integrating with a model-checking engine, is shortly discussed.