Hydrodynamic model application to create a reverse oil cone in water-oil zones

For the conditions of the development of bottom water-drive reservoirs in terrigenous deposits with low permeability of oil-saturated rocks in the dome of the formation, we propose a technology of reverse oil cone creating for effective residual oil reserves development. To visualize the oil recovery process, we created a hydrodynamic model, which makes it possible to increase the efficiency of the proposed technology, as well as to regulate the technology parameters. We considered the issues of the following models creating: the water cone formation during the near-roof part of the formation perforation; the a cone of oil formation in the process of water withdrawing from reservoirs with cutoff water saturation; erosion of the oil cone during its production from the interlayers with the highest oil saturation. The parameters influencing the efficiency of proposed reverse cone technology application are determined.

Cdk5 and GSK3β inhibit fast endophilin-mediated endocytosis

Endocytosis mediates the cellular uptake of micronutrients and cell surface proteins. Fast Endophilin-mediated endocytosis, FEME, is not constitutively active but triggered upon receptor activation. High levels of growth factors induce spontaneous FEME, which can be suppressed upon serum starvation. This suggested a role for protein kinases in this growth factor receptor-mediated regulation. Using chemical and genetic inhibition, we find that Cdk5 and GSK3β are negative regulators of FEME. They antagonize the binding of Endophilin to Dynamin-1 and to CRMP4, a Plexin A1 adaptor. This control is required for proper axon elongation, branching and growth cone formation in hippocampal neurons. The kinases also block the recruitment of Dynein onto FEME carriers by Bin1. As GSK3β binds to Endophilin, it imposes a local regulation of FEME. Thus, Cdk5 and GSK3β are key regulators of FEME, licensing cells for rapid uptake by the pathway only when their activity is low.

The mechanisms of formation of some small cones in Chryse Planitia on Mars

<p><strong>Introduction: </strong>Small cones are common on Mars. Many cones form subparallel chains several kilometers in length. Their origin is discussed in many papers, however, the mechanism of their formation is not explained [1].</p><p>In the present paper, we deal with a small region in Chryse Planitia ( ~38<sup>o</sup>13′ N and ~319<sup>o</sup>25’ E). The region is covered by lacustrine deposits.</p><p>    On Mars, chains of small cones occupy vast areas. Therefore, we try to explain the existence of the chains by specific conditions on Mars. We focus on the hypothesis connecting the formation of cones with the loss of water from the regolith due its instability. See e.g. [1], [2], [4], [5].</p><p><strong> </strong></p><p><strong>Mechanism of cones formation: </strong>We consider 3 mechanisms of cone formation: (i) a grains’ ejection, (ii) from mud or fluidized sand and (iii) explosive formation. The (iii) and (ii) are possible with additional heat sources only.</p><p>    Assuming that only heat of melting was used for vaporization, then only ~13% of liquid water will be vaporized, If the outgassing effect is to be regolith without water, then there must be also other heat sources. Therefore we consider two coexisting factors required for cones formation: (1) the presence of water in the regolith and (2) some additional heating, e.g. magma intrusion.</p><p>    The formation of a chain of cones is possible in two situations:</p><p>(a) above a linear structure containing water and areal heating. Outcrops of aquifers could serve as linear sources of volatiles.</p><p>(b) above a linear source of magmatic heat and the areal aquifer. A dike could serve as linear source of heat.</p><p><strong> </strong></p><p><strong>Conclusions and future plans;</strong></p><p>1) Considered cones could be a result of outgassing of regolith due to pressure drop.</p><p>2) Subparallel chains of cones were formed along the outcrops of volatile-rich sediments.</p><p>3) Numerical modeling indicates that small magma intrusions may not be enough for completely degassing some aquifers.</p><p><strong> </strong></p><p><strong>Acknowledgments:</strong> This study was supported by statutory project of Institute of Geophysics of University of Warsaw. We are also grateful to prof. W. Kofman and dr. J. Ciążela for their remarks.</p><p><strong> </strong></p><p><strong>References</strong></p><p>[1] Fagents, S., Thordarson, T., (2007) The Geology of Mars: Evidence from Earth-Based Analogs, ed. Mary Chapman. Cambridge Univ. Press. [2] Brož,, et al. (2019) JGR: Planets. 124, 703–720. [3] Rotto, S., Tanaka, K. L. (1995) Geologic/ geomorphologic map of the Chryse Planitia: region of Mars. USGS. [4] Barlow, N.G. (2010) GSA Bulletin (2010) 122 (5-6): 644–657. [5] Brož, P., et al. (2020) Nature Geoscience. 13, 403–407.</p>

System for preventing the water cone formation in gas deposits with low gas thickness

The article describes the problem of water cone formation in gas deposits of small gas-saturated thickness. The process of pulling the water cone into the production well is analyzed. The most popular and effective methods of solving this problem are presented. A method of using an electric screw pump to prevent water accumulation in the bottomhole zone is proposed. The method of calculating the optimal pump flow rate, which allows operating the well without its overheating, is considered.

Introducing platform surface interior angle (PSIA) and its role in flake formation, size and shape

Four ways archaeologists have tried to gain insights into how flintknapping creates lithic variability are fracture mechanics, controlled experimentation, replication and attribute studies of lithic assemblages. Fracture mechanics has the advantage of drawing more directly on first principles derived from physics and material sciences, but its relevance to controlled experimentation, replication and lithic studies more generally has been limited. Controlled experiments have the advantage of being able to isolate and quantify the contribution of individual variables to knapping outcomes, and the results of these experiments have provided models of flake formation that when applied to the archaeological record of flintknapping have provided insights into past behavior. Here we develop a linkage between fracture mechanics and the results of previous controlled experiments to increase their combined explanatory and predictive power. We do this by documenting the influence of Herztian cone formation, a constant in fracture mechanics, on flake platforms. We find that the platform width is a function of the Hertzian cone constant angle and the geometry of the platform edge. This finding strengthens the foundation of one of the more influential models emerging from the controlled experiments. With additional work, this should make it possible to merge more of the experimental results into a more comprehensive model of flake formation.

Secondary Breakup Characteristics and Mechanism of Single Electrified Al/N-Decane Nanofluid Fuel Droplet in Electrostatic Field

The combustion characteristics of nanofluid fuels have been widely investigated, but rare studies on the atomization were reported. Atomization is an imperative and crucial step to improve the combustion performance of nanofluid fuels, and the secondary breakup of droplets is an important segment for atomization to produce uniform fine droplets and distribute nanoparticles in each droplet. This paper firstly presents the secondary breakup characteristics of single electrified Al/n-decane nanofluid fuel droplets and revealed the mechanism of the secondary breakup. The results demonstrated that fine droplets could be produced in the electrostatic field and Al nanoparticles were distributed in each droplet. Before the breakup, the single electrified droplets experienced surface charge transportation, deformation, and Taylor cone formation. A gradient of the electric field deformed the droplet to produce the Taylor cone. As the Taylor cones were stabilized, the fluid was extruded from the tips of stable Taylor cones to produce jet filament parallel to the electric field direction and correspondingly broke up into fine sub droplets. At the nanoparticle concentration range of 1.0~10 mg/mL, the minimum average diameter of breakup sub droplets could achieve ~55.4 μm at 6.0 mg/mL. The Al nanoparticle concentration had a significant effect on the breakup performance by influencing the physical properties and charging. The order of the Charge-to-Mass ratio magnitude was 10−7~10−5 C/kg. Furthermore, the secondary breakup mechanism of single electrified nanofluid fuel droplets in the uniform electrostatic field was revealed by analyzing the droplet surface charge, deformation, Taylor cone formation, and nanoparticle concentration effect.

Dynamics of Flexoelectric Materials: Subsonic, Intersonic, and Supersonic Ruptures and Mach Cone Formation

Motivated by recent, unexpected, experimental observations of “intersonic” rupture growth in which both shear and dilatational Mach fronts were observed at the tips of dynamic frictional ruptures propagating at rupture speeds below the dilatational wave speed of the surrounding solid, and we formulate the general dynamic flexoelectric problem and we investigate its plane strain/plane polarization specialization. The coupling of the mechanical problem is analogous to a problem of Toupin–Mindlin gradient elasticity, where two micromechanical characteristic lengths and two microinertial lengths emerge as a combination of the mechanical, dielectric, and flexoelectric constants. The solution of the rupture growth problem allows us to provide an explanation of the experimental results. This becomes possible since flexoelectricity predicts a new aspect that was not observed in the classical analysis: subsonic super shear and supersonic crack tip (or rupture) motions are not related exclusively with the problem being elliptic or hyperbolic, respectively. This is due to the influence of the microinertial lengths, which, in addition to the ratios of the rupture to the wave speeds, also affect the slopes of the Mach cones. Moreover, we are able to explain the experimental paradox of the observation of double Mach cone pairs at the tips of supershear, but subsonic, frictional, ruptures in poly-methyl-methacrtylate (PMMA) by demonstrating that both dilatational and shear Mach cones could appear in flexoelectric solids at rupture speeds below the material dilatation wave speed, something that is impossible from the classical elasticity analysis and is due to the dispersive nature of the present problem. Our analysis is of relevance to the dynamic deformation and fracture of both synthetic and naturally occurring flexoelectric materials and systems, with implications to both engineering and earthquake source mechanics.

Growth-Promoting Treatment Screening for Corticospinal Neurons in Mouse and Man

Neurons of the central nervous system (CNS) that project long axons into the spinal cord have a poor axon regenerative capacity compared to neurons of the peripheral nervous system. The corticospinal tract (CST) is particularly notorious for its poor regeneration. Because of this, traumatic spinal cord injury (SCI) is a devastating condition that remains as yet uncured. Based on our recent observations that direct neuronal interleukin-4 (IL-4) signaling leads to repair of axonal swellings and beneficial effects in neuroinflammation, we hypothesized that IL-4 acts directly on the CST. Here, we developed a tissue culture model for CST regeneration and found that IL-4 promoted new growth cone formation after axon transection. Most importantly, IL-4 directly increased the regenerative capacity of both murine and human CST axons, which corroborates its regenerative effects in CNS damage. Overall, these findings serve as proof-of-concept that our CST regeneration model is suitable for fast screening of new treatments for SCI.