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ABSTRACT Epithelial tissues serve as critical barriers in metazoan organisms, maintaining structural integrity and facilitating essential physiological functions. Epithelial cell polarity regulates mechanical properties, signaling, and transport, ensuring tissue organization and homeostasis. However, the barrier function is challenged by cell turnover during development and maintenance. To preserve tissue integrity while removing dying or unwanted cells, epithelial tissues employ cell extrusion. This process removes both dead and live cells from the epithelial layer, typically causing detached cells to undergo apoptosis. Transformed cells, however, often resist apoptosis, leading to multilayered structures and early carcinogenesis. Malignant cells may invade neighboring tissues. Loss of cell polarity can lead to multilayer formation, cell extrusion, and invasion. Recent studies indicate that multilayer formation in epithelial cells with polarity loss involves a mixture of wild‐type and mutant cells, leading to apical or basal accumulation. The directionality of accumulation is regulated by mutations in polarity complex genes. This phenomenon, distinct from traditional apical or basal extrusion, exhibits similarities to the endophytic or exophytic growth observed in human tumors. This review explores the regulation and implications of these phenomena for tissue biology and disease pathology. [ABSTRACT FROM AUTHOR]

The efficiency of gas injection for developing terrigenous deposits within a multilayer producing object is investigated in this article. According to the results of measurements of the 3D hydrodynamic compositional model, an assessment of the oil recovery factor was made. In the studied conditions, re-injection of the associated gas was found to be the most technologically efficient working agent. The factors contributing to the inefficacy of traditional methods of stimulating oil production such as multistage hydraulic fracturing when used to develop low-permeability reservoirs have been analysed. The factors contributing to the inefficiency of traditional oil-production stimulation methods, such as multistage hydraulic fracturing, have been analysed when they are applied to low-permeability reservoirs. The use of a gas of various compositions is found to be more effective as a working agent for reservoirs with permeability less than 0.005 μm². Ultimately, the selection of an agent for injection into the reservoir should be driven by the criteria that allow assessing the applicability of the method under specific geological and physical conditions. In multilayer production objects, gas injection efficiency is influenced by a number of factors, in addition to displacement, including the ratio of gas volumes, the degree to which pressure is maintained in each reservoir, as well as how the well is operated. With the increase in production rate from 60 to 90 m³ / day during the re-injection of produced hydrocarbon gas, this study found that the oil recovery factor increased from 0.190 to 0.229. The further increase in flow rate to 150 m³ / day, however, led to a faster gas breakthrough, a decrease in the amount of oil produced, and a decrease in the oil recovery factor to 0.19 Based on the results of the research, methods for stimulating the formation of low-permeability reservoirs were ranked based on their efficacy. [ABSTRACT FROM AUTHOR]

Inflow Performance Relationships curves are used in the process of assessing the well performances. These characterize the fluid flow through reservoir, being the first step in the optimization process of operating well parameters based on nodal analysis. The IPR curves depend by a lot of factors as: the types of fluids (multiphase or single phase fluids) that flow through reservoir, water cut, bubble point pressure, formation damage, reservoir depletion, productive formation type(multilayer or single layer formation), well trajectory etc. Generally, an oil and gas reservoir is multilayered type and a well can intercept and produce from a number of these layers. In this case, the well completion is choosing to produce simultaneously and separate each layer or to produce commingled fluids from all the intercepted layers. The objective of this paper is to present a method to determine the composite IPR curves in the case of a well which produces from a multilayer formation. It is also analyzes the influence of the productivity indices, layers pressures and bottom hole pressure on these IPR curves. [ABSTRACT FROM AUTHOR]

Abstract: Langmuir films of facial T-shaped amphiphilic liquid crystals were studied at the air–water interface. The liquid crystals were composed of three incompatible segments: a central rigid rodlike p-terphenyl (TP) group, two flexible hydrophobic n-alkyl terminal chains of identical length linked through ether bonds, and one hydrophilic lateral chain of three ethylene oxide units with a carboxyl end group. In order to determine the influence of the alkyl chain length on the characteristics of condensed films three TPs having n-alkyl chains with eight (TP8/3), ten (TP10/3) or 16 (TP16/3) carbon atoms were investigated. Surface pressure – mean molecular area isotherms revealed clear differences. TP8/3 and TP10/3 exhibit an extended plateau region where a phase transition from monolayer to multilayer takes place. On the other hand, the TP16/3 isotherm showed a distinct maximum (‘spike’) corresponding to a surprising surface crystallization process which is reported for the first time for a Langmuir film of a liquid crystal. Brewster angle microscopy clearly confirmed these differences: TP8/3 and TP10/3 formed circular domains with liquid crystalline order, while TP16/3 formed well-defined two-dimensional polycrystalline spherulites which are fractured after further compression. The film thickness determined by X-ray reflectivity measurements correlated with a multilayer formation for TP10/3. The morphology of Langmuir–Blodgett (LB) films transferred onto silicon wafers and studied by atomic force microscopy also confirmed the striking different behavior (multilayer formation vs. 2D crystallization) of the TPs under investigation. [Copyright &y& Elsevier]

Abstract: Equilibrium and dynamic surface tension of non-ionic triblock copolymers, Pluronics, varying in the number of poly(ethylene oxide) and poly(propylene oxide) groups have been measured by means of drop profile tensiometry at the water–hexane interface. The experimental data have been explained on the basis of a theory previously developed for protein solutions . This model assumes the coexistence of different adsorbed states at the interface, depending on the surface coverage. It has been shown that the best fit is achieved when a polylayer adsorption is considered. Reasonable values of the adsorption layer thickness and realistic values of the diffusion coefficient are obtained which validate the model proposed. [Copyright &y& Elsevier]

Abstract: The formation of multilayered interfaces around oil droplets in oil-in-water emulsions provides food technologists with a novel means of improving the quality and stability of many food products, as well as the ability to develop novel encapsulation and delivery systems. This article reviews the basic principles of multilayer emulsion formation, discusses the factors that influence the characteristics of the interfaces formed, and highlights the relationship between interfacial properties and emulsion functionality. Finally, it highlights some potential applications of the multilayer emulsion technology in the food industry for improving the stability of emulsions to environmental stresses or for developing controlled or triggered release systems. [Copyright &y& Elsevier]

Adsorbed gelatin layers have been characterized by measuring the surface equilibrium tension and surface rheological parameters of shear, found by surface creep experiments. After the determination of these parameters the solution below the adsorption layer (gelatin + phosphate buffer) was substituted by a gelatin-free phosphate-buffer-solution. The differences of the parameters calculated before and after the substitution of the bulk phase allowed us to prove some model assumptions of the protein adsorption and to characterize the physical contents of some of the surface rheological parameters determined. The parameters calculated and measured permit the distinction of three different concentration ranges of gelatin: [ABSTRACT FROM AUTHOR]

This paper first defines a multilayer formation control problem, where the agents can receive and transmit information among the layers. A layered distributed finite-time estimator is proposed for agents in each layer to obtain their target positions and velocities based on the information of agents in their prior layers. A model-based control law is then proposed to achieve multilayer formation, where the formation configurations can be constant or time-varying. This paper also gives a clue on multilayer formation control design in the presence of practical issues, such as model uncertainties and loss of velocity measurements. Simulation results are given to show the effectiveness of the proposed approaches with a group of satellites in a time-varying formation case. [ABSTRACT FROM AUTHOR]