There is an urgent need for expanding the number of brain banks serving psychiatric research. We describe here the Psychiatric Disorders arm of the Brain Bank of the Brazilian Aging Brain Study Group (Psy-BBBABSG), which is focused in bipolar disorder (BD) and obsessive compulsive disorder (OCD). Our protocol was designed to minimize limitations faced by previous initiatives, and to enable design-based neurostereological analyses. The Psy-BBBABSG first milestone is the collection of 10 brains each of BD and OCD patients, and matched controls. The brains are sourced from a population-based autopsy service. The clinical and psychiatric assessments were done by an expert team including psychiatrists, through an informant. One hemisphere was perfused-fixed to render an optimal fixation for conducting neurostereological studies. The other hemisphere was comprehensively dissected and frozen for molecular studies. In 20 months, we collected 36 brains. A final report was completed for 14 cases: 3 BDs, 4 major depressive disorders, 1 substance use disorder, 1 mood disorder NOS, 3 obsessive compulsive spectrum symptoms, 1 OCD and 1 schizophrenia. The majority were male (64%), and the average age at death was 67.2 ± 9.0 years. The average postmortem interval was 16 h. Three matched controls were collected. The pilot stage confirmed that the protocols are well fitted to reach our goals. Our unique autopsy source makes possible to collect a fairly number of high quality cases in a short time. Such a collection offers an additional to the international research community to advance the understanding on neuropsychiatric diseases.

The rhombohedral twinning in hematite has an important role in the accommodation of the deformation of hematite single crystals and hematite aggregates. It is a contact twinning and occurs as lamellae parallel to the planes of hematite as a result of twin gliding on such planes. On account of the recent applications of electron backscatter diffraction (EBSD) techniques in a wide range of microstructural studies, the determination of symmetry operations that relate crystals in a deformed crystalline aggregate is crucial for the full textural characterization. This study presents an EBSD‐based crystallographic analysis of the rhombohedral twinning on hematite crystals of a naturally deformed banded iron formation. Manipulations of theoretical pole figures depicting the symmetry relation of the rhombohedral twinning and misorientation and crystallographic data obtained by EBSD are used to establish the rotational relationship between twin and parent crystals. A method for determining pairs of axes and angles of rotation was developed which can be extended to any other twin laws or misorientation patterns in any other crystal system. It was found that the hematite rhombohedral twins are related to the parent crystal by an approximately 85° rotation about the 〈〉 directions. Hence it could be determined that this consists of a macroscopic twinning element which is an alternative to the conventional ones used to describe the symmetry of the twin. It also matches microscopic twinning elements for the rhomb twinning law. Additionally, this method allows the determination of the crystallographic orientation of the twin lamellae and which particular 〈〉 axis satisfies the 85°〈〉 pair of rotation. The use of an unambiguous angle–axis pair of rotation allows the identification of twin boundaries in complex and finely grained aggregates and the distinction of twinning laws in a particular crystal.

Shear zones typically interact to form connected systems or networks to accommodate crustal deformation, but our knowledge of how this happens is fragmentary. Understanding branching and interacting shear zones requires knowledge of timing, deformation kinematics, and rheology. The Senador Pompeu, Tauá, and Cococi strike‐slip shear zones of the Borborema Province (NE Brazil) have a central role and location in the Neoproterozoic assembly of Gondwana and provide a means to understand shear zone interaction. We apply (i) U‐Pb in situ SHRIMP analysis of zircons from syntectonic plutons and dykes to constrain the timing of shearing and (ii) vorticity and strain analysis on pluton's megacrystic facies deformed in the magmatic state and during final stages of crystallization. Obtained ages show that the shear zone pair was active under high temperature at 583.5±4.6 Ma, while felsic dykes were emplaced in the brittle regime in the wall rocks. Average vorticity estimates of 0.70 indicate a strong component of pure shear in the shear zones. Despite the transpressional character, the dispersion in estimates of thinning and thickening for the Senador Pompeu shear zone highlights variations of offset rate for the interacting branches that leads to localized transtension. We conclude that the kinematic framework of the Senador Pompeu and Tauá conjugate pair involves the formation of a dextrally closing zipper structure involving the trailing Cococi shear zone to the southwest, which in turn caused the northeastward extrusion of the enclosed crustal wedge and possibly activation of the nappe system of the Ceará Central domain.

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