Klinefelter syndrome: cardiovascular abnormalities and metabolic disorders

Klinefelter syndrome (KS) is one of the most common genetic causes of male infertility. This condition is associated with much comorbidity and with a lower life expectancy. The aim of this review is to explore more in depth cardiovascular and metabolic disorders associated to KS. KS patients have an increased risk of cerebrovascular disease (standardized mortality ratio, SMR, 2.2; 95% confidence interval, CI, 1.6–3.0), but it is not clear whether the cause of the death is of thrombotic or hemorrhagic nature. Cardiovascular congenital anomalies (SMR, 7.3; 95% CI, 2.4–17.1) and the development of thrombosis or leg ulcers (SMR, 7.9; 95% CI, 2.9–17.2) are also more frequent in these subjects. Moreover, cardiovascular abnormalities may be at least partially reversed by testosterone replacement therapy (TRT). KS patients have also an increased probability of endocrine and/or metabolic disease, especially obesity, metabolic syndrome and type 2 diabetes mellitus. The effects of TRT on these abnormalities are not entirely clear

PPM-based Orthogonal Space-Time Coding for IR-UWB MIMO channels affected by Poisson-distributed Multipaths

In this contribution we develop a single Multiple-Input Multiple-Output Impulse Radio UWB (IR-UWB) transceiver for Orthogonal (OPPM) data transmitted over (baseband) multipath faded MIMO channels. The proposed Maximum-Likelihood receiver results to be "partially coherent", because it is optimized to work without any information on the path gains, but only on the knowledge of the arrivals' times of the transmitted signals' replicas. The performance of the proposed transceiver are evaluated via three suitable versions of the Union-Chernoff Bound related to several indoor and outdoor propagation scenarios, and through such limits we introduce a novel family of unitary orthogonal Space-time Block Codes (e.g., the Space-Time OPPM (STOPPM) codes), that are able to attain the maximum of diversity and coding gains. ©2007 IEEE