Notes: Abstract: The regional distribution and local incorporation of [14C]thymidine into a nonextractable tissue fraction, probably DNA, was measured in normal and neo-plastic tissues. We studied brain tumors induced by avian sarcoma virus and ethylnitrosourea, and transplanted RG-2 intracerebral and subcutaneous gliomas. An incorporation quotient, Q, was calculated for different tumor regions and brain from the methanol nonextractable radioactivity in the tissue and the plasma concentration-time integral of thymidine. The incorporation quotient represents the rate of clearance of thymidine from blood and its incorporation into macromolecules (probably I NA). The values of Q were compared with a labeling index measured in the same tissue regions with conventional autoradiography. The following observations were made: (1) the mean plasma half-life of thymidine was 6.5 min; (2) the regional incorporation quotient in tumors varied from values comparable to normal brain to more than 100 times higher; (3) RG-2 tumors had significantly higher Qs than the other tumor models; (4) Q in subcutaneous tumors varied most widely (〉500-fold range); (5) the labeling index reflected the values of Q in some tumor regions but not in others; differences between the two were most frequently related to tumor cell density and the intensity of individual tumor cell labeling. A comparison of these data with previous studies of capillary permeability and blood flow in these tumor models indicates that the incorporation of [14C]thymidine into a nonextractable tissue fraction can be limited by transcapillary transport in brain tumors and by blood flow in systemic tumors, and that thymidine disposition in these tumors is not always indicative of the rate of DNA synthesis.

Notes: Accumulation rates of terrestrial sediment have increased in the past few million years both on and adjacent to continents, although not everywhere. Apparently, erosion has increased in elevated terrain regardless of when last tectonically active or what the present-day climate. In many regions, sediment coarsened abruptly in late Pliocene time. Sparser data suggest increased sedimentation rates at ~15 Ma, approximately when oxygen isotopes in benthic foraminifera imply high-latitude cooling. If climate change effected accelerated erosion, understanding how it did so remains the challenge. Some obvious candidates, such as lowered sea level leading to erosion of continental shelves or increased glaciation, account for increased sedimentation in some, but not all, areas. Perhaps stable climates that varied slowly allowed geomorphic processes to maintain a state of equilibrium with little erosion until ~3-4 Ma, when large oscillations in climate with periods of 20,000-40,000 years developed and denied the landscape the chance to reach equilibrium.

Notes: Fault plane solutions of earthquakes within and on the margins of the Tibetan Plateau show diverse styles of faulting and deformation, with thrust faulting and crustal shortening normal to the margins of the plateau and with normal and strike-slip faulting resulting in roughly east-west crustal extension within the plateau. The direction of overthrusting of the Himalaya onto the Indian Shield is radially outward, varying from southwest in the western Himalaya to south-southeast in the east. Assuming that the Indian Shield behaves rigidly, this requires a west-northwest divergence of western Tibet from southeastern Tibet at a rate of 18 ± 9 mm yr−1, comparable with the rate of convergence at the Himalaya. Fault plane solutions of earthquakes in the southern portion of the Tibet Plateau consistently show large components of normal faulting on roughly north-striking planes and corroborate such extension. Within the high plateau, where elevations exceed 5000 m, normal and strike-slip faulting occur so that an overall east-southeast-west-northwest extension of the region (at about 10 mm yr−1) is partitioned into roughly equal parts of crustal thinning and north-northeast-south-southwest crustal shortening (about 5 mm yr−1). In general, strike-slip faulting characterizes solutions for earthquakes within eastern Tibet, where mean elevations drop below 4500–5000 m, but the orientations of the strike-slip faults vary across the region. In central Tibet, left-lateral slip occurs on planes trending roughly northeast, but for earthquakes farther east, the orientations of that plane become progressively east-west and then southeast. This variation in orientation implies a rotation of material along curved left-lateral shear zones. Thus, the eastward extrusion of Tibet appears to be facilitated not only by rapid left-lateral shear, but also by large clockwise rotations of the material in eastern Tibet. The rate of eastward extrusion of material in eastern Tibet, relative to the Tarim Basin to its north, is roughly 30–40 mm yr−1. Fault plane solutions of earthquakes in the northern and eastern margins of Tibet show large components of thrust faulting, with the P-axes, oriented radially outward from the plateau and approximately perpendicular to the regional topographic contours of the plateau. The orientation of this crustal shortening is northeast-southwest on the northeastern margin, east-west on the eastern margin, and northwest-southeast in the Longmenshan on the southeastern margin. Thus, at least some of the extrusion of eastern Tibet out of India's northward path into Asia is absorbed by crustal shortening on the margins of the plateau. The variation from normal faulting in the high Tibetan Plateau, where elevations exceed 5000 m, to dominantly strike-slip faulting farther east where elevations are lower, and then to thrust faulting on the margins of the plateau, where elevations drop below 3000 m, surely results, at least in part, from a decrease in the value of the vertical stress: the magnitude of the east-west compressive stress need not vary across the plateau.

Notes: Gravity anomalies, including terrain corrections, over the western Alps and the Molasse Basin are within 30 mgal of those calculated assuming local Airy isostatic equilibrium, but isostatic anomalies over regions NW and SE of the Alps exceed 50 mgal. Therefore, mass excesses and deficits that must be supported by the strength of the lithosphere or by dynamically induced stress in the asthenosphere appear to be greater beneath the areas surrounding the Alps than beneath the Alpine chain itself. Attempts to account for the gravity gradient over the Molasse Basin and sub-Alpine chains and the small Bouguer anomalies measured over the elevated areas of the Vosges and Black Forest by the flexure of an elastic plate require an absurd set of parameters. The high elevations of the Vosges and the Black Forest are presumably due to high temperature in the underlying uppermost mantle, but the deviations from isostatic equilibrium, as well as the high temperature, probably result from active upwelling in the asthenosphere beneath this area. The absence of large isostatic anomalies over the Alps and the failure of an elastic model to account for the gravity anomalies over the Molasse Basin suggest that the dynamic processes that flexed the European plate down to form the Molasse Basin and that built the Alpine chain have waned. The late Cenozoic uplift of the Molasse Basin and the Alps might be a consequence of a diminution or termination of downwelling of mantle material beneath the Alps.

Notes: [Auszug] Table 1 Palaeomagnetic poles from Eurasian samples Palaeomagnetic Site location (and age) pole (N, E) Palaeolatitude* Difference! (km) Tibet 30N 91.3E (early Tert. - late Cret.) 67.5 283.1 8 Spitzbergen 79N 15E (late Cret.) 75.0 235.0 18 10 (1,100) ...

Notes: [Auszug] WE apologize to Thirlaway and his colleagues for stating categorically that the shape of the surface wave spectra for discriminating between earthquakes and explosions was suggested prior to our work1 but not tested. The two figures presented by him in the SIPRI ...

Notes: [Auszug] Differences in the spectra of seismic surface waves provide important discriminants between underground explosions and ...

Notes: [Auszug] A simple analogy is made between the tectonics of Asia and deformation in a rigidly indented rigid–plastic solid. India is analogous to the indenter and the great strike-slip faults correspond to slip lines. For various indentation geometries, the sense and linearity (or curvature) of ...

Notes: [Auszug] We have previously4 reconstructed the major plates in the Atlantic and north-eastern Indian Ocean at the time of anomaly 24 (approximately 60 Myr ago according to the magnetic anomaly time scale of Heintzler et al.5). Anomaly 24 is particularly well defined in these oceans, and we estimated that ...