Folding processes and solitary waves in structural geology

Evolution of localized folding patterns in layered elastic and visco-elastic materials is reviewed in the context of compressed geological systems. The thin strut or plate embedded in a visco-elastic medium is used as an archetypal example to describe localized buckles which, in contrast to those from earlier formulations, appear in the absence of triggering imperfections. Structural and material effects are surveyed and important nonlinear characteristics are identified. A brief review of possible methods of analysis is conducted.

Treadmill running protects spinal cord contusion from secondary degeneration

It is known that physical activity triggers changes in the central nervous system Adult rats, trained on treadmills for 4 weeks, and a group of sedentary rats was submitted to contuse moderate spinal cord injury A group of sedentary rats was submitted to a sham operation The trained group continued running on treadmill after lesion for 4 weeks Motor behavior evaluated by BBB score was smaller in the sedentary group compared to the trained rats by 7 days after lesion Computerized activity monitor showed clear-cut differences in spontaneous motor parameters in trained rats only before lesion After surgery, sedentary rats showed changes in motor parameters but not in later periods of analysis Animals were euthanized by 28 days after surgery, and their spinal cords were processed for Nissl staining and immunohistochemistry The number of the remaining neurons and the lesion areal and lesion volume fractions were obtained by stereological method The number of the remaining neurons did not change after training Lesion volume and lesion areal fraction per section were smaller in the trained group Lesion index was more pronounced in the sedentary group Microdensitometric image analysis demonstrated a microglial reaction, astroglial activation, and glial FGF-2 production more pronounced in the spinal cord of sedentary animals GAP-43 was higher in caudal levels of contusion in the sedentary group In conclusion, treadmill running may favor a better functional recovery in the acute period after spinal cord lesion and wound repair processes leading to neuroprotection (C) 2010 Elsevier B V All rights reserved

Arterial and interstitial remodelling processes in non-specific interstitial pneumonia: systemic sclerosis versus idiopathic

Aims: To compare septal and vascular matrix remodelling, vascular occlusion, Pulmonary function tests and survival between two groups: one with idiopathic non-specific interstitial pneumonia (NSIP) and one with NSIP associated with systemic sclerosis (SSc). Methods and results: Pulmonary biopsy specimens were examined from 40 patients, 22 with NSIP and 18 with NSIP associated with SSc. The content of septal collagen and elastic fibres, as well as the elastic fibres in the vascular interstitium, were higher in the SSc group (P = 0.01, P = 0.001 and P < 0.0001, respectively). Among pulmonary function tests. the diffusing capacity for carbon monoxide/alveolar volume was affected to a greater extent in the SSc group (59%) of the predicted value in SSc and 97% in the idiopathic group). There were no differences in collagen content of the vascular interstitium, arterial occlusion, or survival between the two groups. Conclusions: Although the fibrotic process is more intense in the SSc group. it, does not affect the prognosis of these patients. Because the elastotic process is higher in the SSc group, this might suggest that autoimmune inflammatory mechanisms affecting the elastic fibre system play a greater role in the pathogenesis and pulmonary remodelling process of SSc NSIP than in idiopathic NSIP.