Critical features in electromagnetic anomalies detected prior to the L'Aquila earthquake

Electromagnetic (EM) emissions in a wide frequency spectrum ranging from kHz to MHz are produced by opening cracks, which can be considered as the so-called precursors of general fracture. We emphasize that the MHz radiation appears earlier than the kHz in both laboratory and geophysical scale. An important challenge in this field of research is to distinguish characteristic epochs in the evolution of precursory EM activity and identify them with the equivalent last stages in the earthquake (EQ) preparation process. Recently, we proposed the following two epochs/stages model: (i) The second epoch, which includes the finally emerged strong impulsive kHz EM emission is due to the fracture of the high strength large asperities that are distributed along the activated fault sustaining the system. (ii) The first epoch, which includes the initially emerged MHz EM radiation is thought to be due to the fracture of a highly heterogeneous system that surrounds the family of asperities. A catastrophic EQ of magnitude Mw = 6.3 occurred on 06/04/2009 in central Italy. The majority of the damage occurred in the city of L'Aquila. Clear kHz - MHz EM anomalies have been detected prior to the L'Aquila EQ. Herein, we investigate the seismogenic origin of the detected MHz anomaly. The analysis in terms of intermittent dynamics of critical fluctuations reveals that the candidate EM precursor: (i) can be described in analogy with a thermal continuous phase transition; (ii) has anti-persistent behaviour. These features suggest that the emerged candidate precursor could be triggered by microfractures in the highly disordered system that surrounded the backbone of asperities of the activated fault. We introduce a criterion for an underlying strong critical behavior.Comment: 8 pages, 6 figure

Concomitant inflammatory pseudotumor of the liver and spleen

We report the case of a 53-year-old man with inflammatory pseudotumor (IPT) of the liver and spleen. This concomitant association has rarely been reported. The patient presented with a hypoechoic mass in the liver and a clinical picture of recurrent sepsis; hematochemical exams and imaging data were nonspecific. Antibiotic therapy improved the clinical course, but did not resolve it definitively. After 50 days of therapy, as the hepatic mass decreased a similar lesion appeared in the spleen. The final diagnosis was made on splenectomy and an intra-operative biopsy of the residual liver lesion. The diagnostic problems encountered in this very rare association of IPT of the liver and spleen were similar to those for isolated IPT in the respective single organ sites. After 15 months of follow-up, the patient is in good health and no recurrence of symptoms or masses has been observed