It is known that a Sleptsov net, with multiple firing of a transition at a step, runs exponentially faster than a Petri net, opening prospects for its application as a graphical language of ...concurrent programming. We provide a classification of place-transition nets based on firability rules considering general definitions and their strong and weak variants. We introduce and study a strong Sleptsov net, where a transition with the maximal firing multiplicity fires at a step, and prove that it is Turing complete. We follow the proof pattern of Peterson which he applied to prove that an inhibitor Petri net is Turing complete by simulating a Shepherdson and Sturgis register machine. The central construct of our proof is a strong Sleptsov net that checks whether a register value (place marking) equals zero.
The design of immobilized enzyme preparations is an important and relevant area of modern sciences and technologies. Immobilization of enzymes from animal sources (component I) on natural carriers ...(component II) increases the system stability by protecting the active site of the enzyme from deactivation; facilitates the separation and accelerates the recovery of the enzyme. This makes reuse possible and provides a significant reduction in operating costs. Hydrolytic enzymes (such as lipases) and polysaccharides (such as chitosan) are the most promising of such pairs of components. The main attention here is devoted to the discussion on lipase immobilization on polysaccharide (mainly - chitin and chitosan). Based on the analysis of the available literature, the most adequate method is the immobilization of lipase from porcine pancreas (LPP) on polysaccharide particles (such as chitin or chitosan) pre-treated with ultrasound (to increase the particle surface area) and glutaraldehyde (for particle activation) that shows reasonably high LPP activity and stability. In order to increase further the activity of the lipase, some authors proposed to incorporate a spacer in the form of 1,3-diaminopropane (or 1,3-diaminobutane) prior to activation of the surface of the chitosan particles. In particular cases, the use of chitin (instead of chitosan) may be an alternative solution for biotechnological applications.
Recently the idea of constructing “supramolecular enzyme systems” realized in the so-called “coimmobilized multienzymatic systems” strategy. The most fascinating example is the combined assay of a mixture of native LPP, glycerol kinase (from Cellulomonas) and glycerol-3-phosphate oxidase (from Aerococcus viridans) linked by glutaraldehyde to chitosan (as shell for inorganic nanoparticle core). This material was placed on a Pt-electrode as biosensor and was successfully applied for amperometric determination of the triglyceride level in the serum of healthy and diseased person. Thus, the whole innovative research-production sequence is described by Aggarwal V. and Pundir C.S.: from simple components to advanced material and further biomedical application.
Thus, the following approach of lipase immobilization appears the most promising for future applications: a few types of lipases or the combination of LPP with some other enzymes immobilized simultaneously on multifunctional carriers (as nanohybrids of inorganic core and polysaccharide shell).
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•Immobilization of enzymes on natural carriers is an important area of biocolloids.•Lipase immobilized on chitosan particles (ChiPs) is useful for bionanotechnology.•Lipase adsorption on ChiPs (using ultrasound) increases the activity and stability.•Lipase linked to ChiPs (by glutaraldehyde) is useful for particle activation.
Immobilization of enzymes (IoE) from animal origin on natural carriers increases the system stability; facilitates the separation and accelerates the recovery of the enzyme; makes reuse possible; ...provides a significant reduction in operating costs. There are numerous IoE methods and systems, including immobilization of various lipases on major carbohydrate biopolymers (chitin, chitosan, cellulose, etc.), discussed in this review. The key points of the most encouraging methods “for increasing the activity and stability” of such biopolymer systems are the “chitosan particle activation” by “ultra-sonication” and multiplicative “addition of glutaraldehyde” to these abovementioned systems. The design of such complex biopolymer preparations (in their various forms) is an important area of modern agrosciences, biomedicine, veterinary, zootechnology and bionanotechnology.
Glia have been implicated in Alzheimer's disease (AD) pathogenesis. Variants of the microglia receptor triggering receptor expressed on myeloid cells 2 (TREM2) increase AD risk, and activation of ...disease-associated microglia (DAM) is dependent on TREM2 in mouse models of AD. We surveyed gene-expression changes associated with AD pathology and TREM2 in 5XFAD mice and in human AD by single-nucleus RNA sequencing. We confirmed the presence of Trem2-dependent DAM and identified a previously undiscovered Serpina3n
C4b
reactive oligodendrocyte population in mice. Interestingly, remarkably different glial phenotypes were evident in human AD. Microglia signature was reminiscent of IRF8-driven reactive microglia in peripheral-nerve injury. Oligodendrocyte signatures suggested impaired axonal myelination and metabolic adaptation to neuronal degeneration. Astrocyte profiles indicated weakened metabolic coordination with neurons. Notably, the reactive phenotype of microglia was less evident in TREM2-R47H and TREM2-R62H carriers than in non-carriers, demonstrating a TREM2 requirement in both mouse and human AD, despite the marked species-specific differences.
A generalized neighborhood for d-dimensional cellular automata is introduced; it spans the range from von Neumann's to Moore's neighborhood using a parameter which represents the dimension of ...hypercubes connecting neighboring cells. Finite hypercubes and hypertoruses are studied, and the number of neighbors on their boundary and the number of connections between cells are calculated. We come to finite constructs when practically implementing computations of cellular automata. Enumerations of cells, neighbors and connections are considered and implemented in ad-hoc software which generates a canvas of hypercube and hypertorus models in the form of a Petri net. A cell model can be replaced while the underlying canvas of connections remains the same. The generalized neighborhood is extended to include a concept of radius; the number of neighbors is calculated for infinite and finite lattices. For diamond-shaped neighborhoods, a sequence is obtained whose partial sums equal Delannoy numbers.
•A generalized neighborhood for multi-dimensional cellular automata is introduced.•It spans the range from von Neumann's to Moore's neighborhood using a parameter.•The parameter equals the dimension of hypercubes connecting neighboring cells.•Neighbors are enumerated in infinite and finite hypercubes and hypertoruses.•A sequence is obtained whose partial sums equal Delannoy numbers.
Innate lymphoid cells (ILCs) are tissue-resident lymphocytes categorized on the basis of their core regulatory programs and the expression of signature cytokines. Human ILC3s that produce the ...cytokine interleukin-22 convert into ILC1-like cells that produce interferon-γ in vitro, but whether this conversion occurs in vivo remains unclear. In the present study we found that ILC3s and ILC1s in human tonsils represented the ends of a spectrum that included additional discrete subsets. RNA velocity analysis identified an intermediate ILC3-ILC1 cluster, which had strong directionality toward ILC1s. In humanized mice, the acquisition of ILC1 features by ILC3s showed tissue dependency. Chromatin studies indicated that the transcription factors Aiolos and T-bet cooperated to repress regulatory elements active in ILC3s. A transitional ILC3-ILC1 population was also detected in the human intestine. We conclude that ILC3s undergo conversion into ILC1-like cells in human tissues in vivo, and that tissue factors and Aiolos were required for this process.
Metal processing by laser radiation is shown to be a promising way to obtain surfaces with controllable wetting and evaporation characteristics. Such surfaces can be used in designing the modern ...cooling systems based on phase transitions. However, large-scale applications of metal processing by laser radiation are hampered by the lack of a theory that allows predicting the wetting and evaporation of liquid droplets on modified surfaces. In this work, we study a water droplet behavior during its wetting and evaporation on hydrophilic and hydrophobic aluminum alloy surfaces modified by single nanosecond laser pulses. To predict the wettability of the laser-processed surfaces, we proposed to use the empirical correlation of the contact angle on the surface free energy obtained in terms of dynamic contact angles. We analyzed the applicability of two well-known theoretical models to determine the evaporation rates of droplets on hydrophilic and hydrophobic laser-processed surfaces. The Spalding and diffusive evaporation models can be used for water droplet evaporating from the hydrophilic aluminum alloy surface at a temperature difference between the surface and air in the chamber of 0–6.5 K. At higher temperature difference from 6.5 K to 9 K, only the Spalding model is applicable. In the case of the hydrophobic laser-processed aluminum alloy surface, the mass loss rate of evaporating droplet at the temperature difference range of 0–9 K can be predicted by the diffusive model. In addition, this model was found to be appropriate for predicting the geometric dimensions of a droplet evaporating in a pinned contact line mode on hydrophilic surfaces without heating at any stage of its evaporation. The results of this study can be used to predict the wetting and evaporation characteristics of water droplets on aluminum alloy surfaces modified by single nanosecond laser pulses.
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•SFE was used to select laser parameters for changing the surface wetting properties.•The pinning mode of evaporation was the dominant for laser-processed surfaces.•The evaporation of a droplet was studied at low air/surface temperature difference.
•Regenerated cylindrical photocatalytic materials based on ZnO and TiO2.•The created materials most effectively oxidize cationic organic pollutant - methylene blue.•The photocatalytic performance of ...the samples was tested in a solar water treatment plant of flow-through type.
This article considers the possibility of obtaining regenerated photocatalytic materials of cylindrical shape for flow-through water purification systems. The method of cementation in a ceramic base matrix was compared to the method of laser fusion with a ceramic base of standard powder photocatalysts (ZnO, TiO2) according to the criteria of photocatalytic activity. The obtained materials were tested in a flow-through water purification unit (WPU) during the photo-oxidation of cationic - methylene blue (MB) and anionic - methyl orange (MO) model organic pollutants. The efficiency of water purification from MB at three cycles of regeneration of the obtained materials’ photocatalytic surface by layer-by-layer grinding was shown.
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