On time of the triassic rifts system origin in West Siberia

2019 ◽  
Vol 486 (1) ◽  
pp. 88-92
Author(s):  
K. S. Ivanov ◽  
Yu. V. Erokhin

It is commonly supposed that a very substantial volume of early basalt magmatism effused synchronously on Siberia platform and West Siberia in a very short time interval at 249.4 ± 0.5 Ma (Reichow et al., 2002, etc.). This magmatism and induced climate change are considered as a main reason of the most catastrophic in the Earth history extinction at the border of Permian and Triassic time. But these conclusions were based on incomplete and unrepresentative data on West Siberia. We have obtained by analysis of pyroxenes monofraction from kainotype basalts of Guslinskaya P-430 well Ar-Ar age 268.4 ± 7.5 Ma. In Taurovskaya 503 well this age is 268.1 ± 7.5 Ma. Hence, volcanism in axial rift zones of the basement of West Siberia plate began earlier than that considered before and significantly earlier than on Siberia platform.

Were the raw material for forming planets to have the chemical composition usually assumed, considerable segregation of light and heavy elements must have occurred to an extent that varied from one planet to another. The problem of such segregation is examined in the case of a body of the raw material acted upon by its own gravitation. If the material is entirely gaseous, segregation could not occur in any acceptable time. This shows that some other phase must have played a part, and so confirms the view that the planets were formed ‘cold Dust-grains provide the phase most likely to be required, but grains of normal interstellar dust would settle too slowly; there must have been some adhesion of such grains to form at any rate a relatively small number of somewhat larger grains. After some discussion of the resistance offered by a gas to a grain moving through it, formulae are given for characteristic times associated with various cases of such motion. These are applied to a proto-planet of the sort contemplated in one particular theory of the origin of the solar system (McCrea i 960). If some adhesion of grains results from encounters between them produced by thermal agitation, then more considerable adhesion or accretion will occur when an enlarged grain falls towards the centre of such a proto-planet. It is shown that this accounts for: (a) the existence of planetesimals having diameter of order 1 m near the centre of the proto-planet, (6) the aggregation of such planetesimals into a body of planetary mass, (c) the release of energy that could account for the dispersal of the light materials. These processes could occur in an acceptably short time interval. The formulae are also applied, more briefly, to a body of material similar to a ‘primary object’ of the sort considered by Urey (1964). They indicate that there should be even less difficulty in accounting for segregation of heavy material in this case. However, if segregation could occur as suggested in the first application, it may be difficult to see how material could reach the greater density in the second case without some segregation having already taken place. If this work is correct, a solid body like the Earth can come into being only because of the prior existence of the smallest known naturally occurring bodies in the cosmos, the interstellar grains; an Earth exists because a galaxy is slightly dusty.


1998 ◽  
Vol 1644 (1) ◽  
pp. 142-149 ◽  
Author(s):  
Gang-Len Chang ◽  
Xianding Tao

An effective method for estimating time-varying turning fractions at signalized intersections is described. With the inclusion of approximate intersection delay, the proposed model can account for the impacts of signal setting on the dynamic distribution of intersection flows. To improve the estimation accuracy, the use of preestimated turning fractions from a relatively longer time interval has been proposed to serve as additional constraints for the same estimation but over a short time interval. The results of extensive simulation experiments indicated that the proposed method can yield sufficiently accurate as well as efficient estimation of dynamic turning fractions for signalized intersections.


2020 ◽  
pp. 5-13
Author(s):  
Vishal Dubey ◽  
◽  
◽  
◽  
Bhavya Takkar ◽  
...  

Micro-expression comes under nonverbal communication, and for a matter of fact, it appears for minute fractions of a second. One cannot control micro-expression as it tells about our actual state emotionally, even if we try to hide or conceal our genuine emotions. As we know that micro-expressions are very rapid due to which it becomes challenging for any human being to detect it with bare eyes. This subtle-expression is spontaneous, and involuntary gives the emotional response. It happens when a person wants to conceal the specific emotion, but the brain is reacting appropriately to what that person is feeling then. Due to which the person displays their true feelings very briefly and later tries to make a false emotional response. Human emotions tend to last about 0.5 - 4.0 seconds, whereas micro-expression can last less than 1/2 of a second. On comparing micro-expression with regular facial expressions, it is found that for micro-expression, it is complicated to hide responses of a particular situation. Micro-expressions cannot be controlled because of the short time interval, but with a high-speed camera, we can capture one's expressions and replay them at a slow speed. Over the last ten years, researchers from all over the globe are researching automatic micro-expression recognition in the fields of computer science, security, psychology, and many more. The objective of this paper is to provide insight regarding micro-expression analysis using 3D CNN. A lot of datasets of micro-expression have been released in the last decade, we have performed this experiment on SMIC micro-expression dataset and compared the results after applying two different activation functions.


2018 ◽  
Vol 21 (10) ◽  
pp. 979-984 ◽  
Author(s):  
Chiara Adami ◽  
Elena Lardone ◽  
Paolo Monticelli

Objectives The aim of this study was to compare the Electronic von Frey Anaesthesiometer (EVF) and the Small Animal ALGOmeter (SMALGO), used to measure sensory thresholds in 13 healthy cats at both the stifle and the lumbosacral joint, in terms of inter-rater and inter-device reliability. Methods Two independent observers carried out the sets of measurements in a randomised order, with a 45 min interval between them, in each cat. The inter-rater and inter-device reliability were evaluated by calculating the inter-rater correlation coefficient (ICC) for each pair of measurements. The Bland–Altman method was used as an additional tool to assess the level of agreement between the two algometers. Results The mean ± SD sensory thresholds measured with the EVF were 311 ± 116 g and 378 ± 178 g for the stifle and for the lumbosacral junction, respectively, whereas those measured with the SMALGO were 391 ±172 g and 476 ± 172 g. The inter-rater reliability was fair (ICC >0.4) for each pair of measurements except those taken at the level of the stifle with the SMALGO, for which the level of agreement between observers A and B was poor (ICC = 0.01). The inter-device reliability was good (ICC = 0.73; P = 0.001). The repetition of the measurements affected reliability, as the thresholds obtained after the 45 min break were consistently lower than those measured during the first part of the trial ( P = 0.02). Conclusions and relevance The EVF and the SMALGO may be used interchangeably in cats, especially when the area to be tested is the lumbosacral joint. However, when the thresholds are measured at the stifle, the inter-observer reliability is better with the EVF than with the SMALGO. The reliability decreases when the measurements are repeated within a short time interval, suggesting a limited clinical applicability of quantitative sensory testing with both algometers in cats.


1989 ◽  
Vol 21 (1) ◽  
pp. 1-19 ◽  
Author(s):  
H. R. Lerche ◽  
D. Siegmund

Let T be the first exit time of Brownian motion W(t) from a region ℛ in d-dimensional Euclidean space having a smooth boundary. Given points ξ0 and ξ1 in ℛ, ordinary and large-deviation approximations are given for Pr{T < ε |W(0) = ξ0, W(ε) = ξ 1} as ε → 0. Applications are given to hearing the shape of a drum and approximating the second virial coefficient.


Author(s):  
Laura Mitrea ◽  
Bernadette-Emoke Teleky ◽  
Loredana-Florina Leopold ◽  
Silvia-Amalia Nemes ◽  
Diana Plamada ◽  
...  

Author(s):  
Victor Birman ◽  
Sarp Adali

Abstract Active control of orthotropic plates subjected to an impulse loading is considered. The dynamic response is minimized using in-plane forces or bending moments induced by piezoelectric stiffeners bonded to the opposite surfaces of the plate and placed symmetrically with respect to the middle plane. The control forces and moments are activated by a piece-wise constant alternating voltage with varying switch-over time intervals. The magnitude of voltage is bounded while the switch-over time intervals are constantly adjusted to achieve an optimum control. Numerical examples presented in the paper demonstrate the effectiveness of the method and the possibility of reducing the vibrations to very small amplitudes within a short time interval which is in the order of a second.


Geosciences ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 416
Author(s):  
Angela Baldanza ◽  
Roberto Bizzarri ◽  
Francesco Posati ◽  
Manuel Ravoni

Although drillholes in modern and ancient ostracods are known, the record is relatively scarce when compared to other taxa, and mainly exist with reference to the marine environment. Moreover, less is known about perforated ostracods, and more generally, about bioerosion in freshwater environments. Traces of predation on freshwater ostracods are reported for the first time in deep-lake deposits belonging to the early Pleistocene Fosso Bianco Unit, and outcropping in the Cava Nuova section (Umbria, central Italy). Deposits are mainly clay to silty clay and sand; the fossil record is sparse, and is mainly comprised of very rare gastropods and bivalves, ostracods and plant remains (leaves, seeds and wood’s fragments). The association of ostracods consists of Candona (Neglecandona) neglecta, Caspiocypris basilicii, Caspiocypris tiberina, Caspiocypris perusia, Caspiocypris tuderis, Caspiocypris posteroacuta, and Cyprideis torosa. The Caspiocypris group, considered to be endemic to the grey clays of the Fosso Bianco Unit, present the majority of specimens affected by predation, with a prevalence of predated female valves and a comparable number of right and left predated valves, while only a few of Candona(N.) neglecta (adult and juvenile) valves are perforated. Traces of predation for nourishment, represented by microborings of different types, were abscribed to the ichnospecies Oichnus paraboloides Bromley 1981, Oichnus simplex Bromley 1981, Oichnus gradatus Nielsen and Nielsen 2001, Oichnus ovalis Bromley 1993, and Dipatulichnus rotundus Nielsen and Nielsen 2001. Microboring affected both adult and juvenile specimens, evidencing prey–predator coexistence in the same environment over a long period of time. This report makes a fundamental contribution to the knowledge of predation in this peculiar confined environment, also suggesting prey–predator relations over a relatively short time interval (80–160 ka).


1987 ◽  
Vol 63 (2) ◽  
pp. 778-784 ◽  
Author(s):  
D. A. Rickaby ◽  
C. A. Dawson ◽  
J. H. Linehan ◽  
T. A. Bronikowski

To gain insight into the changes occurring in alveolar vessels when alveolar pressure exceeds venous pressure at the downstream end of the alveolar vessels (zone 2), we compared the uptake of serotonin and the extravascular volume accessible to 3HOH (Qev) under zone 2 and 3 conditions in isolated dog lung lobes. We also examined the influence of occluding some of the small pulmonary arteries with 58- to 548-micron-diam beads on the serotonin uptake and Qev. We found that, with the bead embolization, both the serotonin uptake and the Qev were reduced, whereas the change from zone 3 to 2 reduced serotonin uptake but did not change Qev. A plausible explanation for these observations is that the beads occluded vessels that were relatively large compared with those in which significant transvascular 3HOH exchange and serotonin uptake take place. Perfusion ceased in the collection of capillaries normally served by the obstructed arteries. Thus the extravascular water and the serotonin uptake sites downstream from the obstructions were not accessible to the indicators during the short time interval of the indicator passage through the lung. On the other hand, the change from zone 3 to zone 2 resulted in the collapse of small individual capillary segments within the alveolar vessel bed. Since the serotonin does not readily diffuse from the vessels through the tissue, it could not reach the endothelial cells of the collapsed capillaries. However, since the distances for diffusion between collapsed capillaries and neighboring perfused capillaries were small, the more highly diffusible 3HOH had access to the same Qev under both zone 2 and 3 conditions.(ABSTRACT TRUNCATED AT 250 WORDS)


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