To study the rigidity of the Pacific and Farallon plates between 72 and 35 Ma, we analyzed the magnetic anomalies and fracture zones in the Pacific Ocean between longitudes 125°W–180° and latitudes 43°S–60°N. A set of consistent rotations indicates that the Pacific and Farallon plates between the Pioneer and Agassiz fracture zones were rigid plates between 72 and 35 Ma. Thus the location of a missing Tertiary boundary, within the Pacific or Antarctic plates, is restricted to be south of latitude 43°S. The Farallon plate broke into two plates at the time of the change in the Pacific‐Farallon spreading direction north of the Pioneer and Mendocino fracture zones, sometime between 59 and 49 Ma. The northern fragment, termed the Vancouver plate, was subducted beneath most of North America. We present rotations and uncertainties for the histories of motion of the Pacific and Kula plates from anomaly 32 to anomaly 25, of the Pacific and Vancouver plates from anomaly 21 to anomaly 13, and of the Pacific and Farallon plates from anomaly 32 to anomaly 13.

Three broadband stations operated from March 1997 to September 1998 in the Amazon region north of Manaus, Brazil, which, including the IRIS station PTGA (Pitinga), covered an area of roughly 60 × 200 km. Applying the receiver function technique to determine the crustal structure, there is evidence for an increase of the Moho depth from about 38 km below the Amazon Basin to approximately 48 km north of the basin. In addition, we analyzed the polarization of SKS‐waves to determine anisotropy. The observed splitting parameters in a majority of the data set can be accounted for by a layer of axial symmetric anisotropy with the fast direction oriented roughly N110E. This direction cannot be associated with the present‐day plate motion of the South American plate. However, the anisotropy may be related to a lithospheric fabric that was generated during the early tectonic history of the Amazonian Craton.

Although some pituitary adenomas may have an aggressive behavior, the vast majority are benign. There are still controversies about predictive factors regarding the biological behavior of these particular tumors. This study evaluated potential markers of invasion and proliferation compared to current classification patterns and epidemiogeographical parameters. The study included 50 patients, operated on for tumors greater than 30 mm, with a mean postoperative follow-up of 15.2 ± 4.8 years. Pituitary magnetic resonance was used to evaluate regrowth, invasion, and extension to adjacent tissue. Three tissue biomarkers were analyzed: p53, Ki-67, and c-erbB2. Tumors were classified according to a combination of histological and radiological features, ranging from noninvasive and nonproliferative (grade 1A) to invasive-proliferative (grade 2B). Tumors grades 2A and 2B represented 42% and 52%, respectively. Ki-67 (p = 0.23) and c-erbB2 (p = 0.71) had no significant relation to tumor progression status. P53 (p = 0.003), parasellar invasion (p = 0.03), and classification, grade 2B (p = 0.01), were associated with worse clinical outcome. Parasellar invasion prevails as strong predictive factor of tumor recurrence. Severe suprasellar extension should be considered as invasion parameter and could impact prognosis. No environmental factors or geographical cluster were associated with tumor behavior.

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