Morphological Analysis of Topolog Basin Fluvial Terraces: A Valleys System Evolution Approach

<p>The Western Kunlun Range is a mountain range located at the northwestern boundary of the Tibetan Plateau, facing the Tarim Basin. Our previous combined structural and morphological investigations of the mountain front, nearby the city of Pishan where a Mw 6.4 earthquake occurred in 2015, revealed the existence of a duplex uplifting Cenozoic strata, in which only the most frontal blind ramp is presently active and slips at a probable rate of 2 to 2.5 mm/yr. Located ~100 km further east along the mountain front, the Hotan anticline seems to present a different structure from surface geology, as older strata from Mesozoic and Paleozoic outcrop. Additionally, some authors proposed that the deformation would be here accommodated by a large blind basement thrust sheet, in clear contrast with the duplexes documented further west.</p><p>To further document potential lateral variations in the structural style and how they may affect the kinematics of active deformation along the mountain front of the Western Kunlun, we carry out a structural and morphological analysis of the Hotan anticline. We build structural cross-sections based on seismic reflection profiles, and calculate the incremental uplift recorded by dated fluvial terraces to quantify shortening rates over the last ~300 kyr. Our analysis reveals that a duplex structure, located below the basement thrust sheet, presently accommodates active deformation at a rate of 0.5 to 2.5 mm/yr, with a preferred rate of ~1.6 to 2.3 mm/yr. In more detail, uplifted terraces reveal that all ramps of the duplex are active in the case of the Hotan anticline, while only the most frontal ramp is documented as active in the case of the Pishan anticline further west. These results indicate that the style and rate of active shortening are rather homogeneous all along the mountain front, in contrast with the first impression provided by surface geology. Moreover, the discrepancy between surface geology and active morphology reveals progressive structural changes over geological times, from a blind basement ramp to duplexes. However, in the details, active deformation still remains segmented as its partitioning on the various ramps of the duplexes is variable along strike.</p>

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Structural and Chemical Studies of Pathological Fibers in Human Neurofibrillary Degeneration

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012031x ◽

1985 ◽

Vol 43 ◽

pp. 726-729

Author(s):

K.S. Kosik ◽

L.K. Duffy ◽

S. Bakalis ◽

C. Abraham ◽

D.J. Selkoe

Keyword(s):

Monoclonal Antibodies ◽

Alzheimer Disease ◽

Human Brain ◽

Neurofibrillary Tangles ◽

Morphological Analysis ◽

High Specificity ◽

Cytoskeletal Proteins ◽

Neuritic Plaque ◽

Protein Chemistry ◽

Chemical Studies

The major structural lesions of the human brain during aging and in Alzheimer disease (AD) are the neurofibrillary tangles (NFT) and the senile (neuritic) plaque. Although these fibrous alterations have been recognized by light microscopists for almost a century, detailed biochemical and morphological analysis of the lesions has been undertaken only recently. Because the intraneuronal deposits in the NFT and the plaque neurites and the extraneuronal amyloid cores of the plaques have a filamentous ultrastructure, the neuronal cytoskeleton has played a prominent role in most pathogenetic hypotheses.The approach of our laboratory toward elucidating the origin of plaques and tangles in AD has been two-fold: the use of analytical protein chemistry to purify and then characterize the pathological fibers comprising the tangles and plaques, and the use of certain monoclonal antibodies to neuronal cytoskeletal proteins that, despite high specificity, cross-react with NFT and thus implicate epitopes of these proteins as constituents of the tangles.

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