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2-Deoxy-2-[18F]fluoro-d-glucose positron emission tomography (FDG-PET) is widely used to study cerebral glucose metabolism. Here, we investigated whether the FDG-PET signal is directly influenced by microglial glucose uptake in mouse models and patients with neurodegenerative diseases. Using a recently developed approach for cell sorting after FDG injection, we found that, at cellular resolution, microglia displayed higher glucose uptake than neurons and astrocytes. Alterations in microglial glucose uptake were responsible for both the FDG-PET signal decrease in Trem2-deficient mice and the FDG-PET signal increase in mouse models for amyloidosis. Thus, opposite microglial activation states determine the differential FDG uptake. Consistently, 12 patients with Alzheimer’s disease and 21 patients with four-repeat tauopathies also exhibited a positive association between glucose uptake and microglial activity as determined by 18F-GE-180 18-kDa translocator protein PET (TSPO-PET) in preserved brain regions, indicating that the cerebral glucose uptake in humans is also strongly influenced by microglial activity. Our findings suggest that microglia activation states are responsible for FDG-PET signal alterations in patients with neurodegenerative diseases and mouse models for amyloidosis. Microglial activation states should therefore be considered when performing FDG-PET.

The ignition technology is the key of in-situ combustion, which determines the start of in-situ combustion. This paper proposes a droppable solid fuel igniter for in-situ combustion based on the principle of traditional igniter, which aims to design a droppable solid fuel igniter and demonstrate the feasibility of the igniter. The droppable solid fuel igniter can not only guarantee ignition efficiency, but also avoid the pressure fluctuation caused by lifting artificial igniter in recovery process. Firstly, the structure and fuel of the igniter are designed. Industrial solid fuel with hexamethylenetetramine and multipurpose solid fuel with gangue can both meet the ignition requirements of heat and structure. Then, the feasibility of the igniter is studied by oxidation kinetics and thermodynamics formulas. Finally, the applicable conditions of the igniter are obtained by sensitivity analysis. The results show that the reservoir thickness is the key factor if the igniter length is no more than 20 m. This igniter has strong feasibility if the reservoir thickness is less than 12.8 m, but ignition temperature and initial layer temperature should be considered if reservoir thickness is larger than 12.8 m. In theory, the droppable solid fuel igniter can be used in artificial ignition under certain conditions.

This article examines the problems of capitalist relations in the Russian economy, the influence of capital on state structures, and the development of capitalism in Russia at the beginning of the 20th century. The problem of the development of capitalism in Russia is viewed from the standpoint of the concept of a revolutionary period. Concrete revolutions should be viewed as a manifestation of the processes of stagnation of the Russian economy.Despite the noticeable development of certain heavy industries and the intensive construction of railways, Russia was inferior to some Western countries in terms of qualitative indicators of economic growth. In Russia, capitalism did not exist in the form of a system, but as a structure that did not have the potential for development. This must be taken into account when assessing the current state of the "capitalist" system in Russia and the prospects for its further development.

GRN haploinsufficiency causes frontotemporal lobar degeneration and results in microglial hyperactivation, lysosomal dysfunction and TDP-43 deposition. To understand the contribution of microglial hyperactivation to pathology we evaluated genetic and pharmacological approaches suppressing TREM2 dependent transition of microglia from a homeostatic to a disease associated state. Trem2 deficiency in Grn KO mice led to a reduction of microglia activation. To explore antibody-mediated pharmacological modulation of TREM2-dependent microglial states, we identified antagonistic TREM2 antibodies. Treatment of macrophages from GRN-FTLD patients with these antibodies allowed a complete rescue of elevated levels of TREM2 together with increased shedding and reduction of TREM2 signaling. Furthermore, antibody-treated PGRN deficient hiMGL showed dampened microglial hyperactivation, reduced TREM2 signaling and phagocytic activity, however, lack of rescue of lysosomal dysfunction. Similarly, lysosomal dysfunction, lipid dysregulation and glucose hypometabolism of Grn KO mice were not rescued by TREM2 ablation. Furthermore, NfL, a biomarker for neurodegeneration, was elevated in the Grn/Trem2 KO. These findings suggest that microglia hyperactivation is not necessarily contributing to neurotoxicity, and instead demonstrates that TREM2 exhibits neuroprotective potential in this model.

Parallax error is a common issue in high-resolution preclinical positron emission tomography (PET) scanners as well as in clinical scanners that have a long axial field of view (FOV), which increases estimation uncertainty of the annihilation position and therefore degrades the spatial resolution. A way to address this issue is depth-of-interaction (DOI) estimation. In this work we propose two machine learning-based algorithms, a dense and a convolutional neural network (NN), as well as a multiple linear regression (MLR)-based method to estimate DOI in depolished PET detector arrays with single-sided readout. The algorithms were tested on an 8× 8 array of 1.53× 1.53× 15 mm3 crystals and a 4× 4 array of 3.1× 3.1× 15 mm3 crystals, both made of Ce:LYSO scintillators and coupled to a 4× 4 array of 3× 3 mm3 silicon photomultipliers (SiPMs). Using the conventional linear DOI estimation method resulted in an average DOI resolution of 3.76 mm and 3.51 mm FWHM for the 8× 8 and the 4× 4 arrays, respectively. Application of MLR outperformed the conventional method with average DOI resolutions of 3.25 mm and 3.33 mm FWHM, respectively. Using the machine learning approaches further improved the DOI resolution, to an average DOI resolution of 2.99 mm and 3.14 mm FWHM, respectively, and additionally improved the uniformity of the DOI resolution in both arrays. Lastly, preliminary results obtained by using only a section of the crystal array for training showed that the NN-based methods could be used to reduce the number of calibration steps required for each detector array.

This article examines the problems of capitalist relations in the Russian economy, the influence of capital on state structures, and the development of capitalism in Russia at the beginning of the 20th century. The problem of the development of capitalism in Russia is viewed from the standpoint of the concept of a revolutionary period. Concrete revolutions should be viewed as a manifestation of the processes of stagnation of the Russian economy.Despite the noticeable development of certain heavy industries and the intensive construction of railways, Russia was inferior to some Western countries in terms of qualitative indicators of economic growth. In Russia, capitalism did not exist in the form of a system, but as a structure that did not have the potential for development. This must be taken into account when assessing the current state of the "capitalist" system in Russia and the prospects for its further development.

Alpha-fetoprotein (AFP) is a biological drug candidate of high medicinal potential in the treatment of autoimmune diseases, cancer, and regenerative medicine. Large-scale production of recombinant human alpha-fetoprotein (rhAFP) is desirable for structural and functional studies and applied research. In this study we cloned and expressed in the secreted form wild-type glycosylated human rhAFP and non-glycosylated mutant rhAFP(0) (N233S) in the yeast strain Saccharomyces cerevisiae with multiple chromosome-integrated synthetic human AFP genes. RhAFP and rhAFP(0) were successfully produced and purified from the culture liquids active naturally folded proteins. Elimination of the glycosylation by mutation reduced rhAFP(0) secretion about threefold as compared to the wild-type protein showing critical role of the N-linked glycan for heterologous protein folding and secretion. Structural similarity of rhAFP and rhAFP(0) with natural embryonic eAFP was confirmed by circular dichroism technique. Functional tests demonstrated similar type of tumor suppressive and immunosuppressive activity for both recombinant species rhAFP and rhAFP(0) as compared to natural eAFP. It was documented that both types of biological activities attributed to rhAFP and rhAFP(0) are due to the fast induction of apoptosis in tumor cells and mitogen-activated lymphocytes. Despite the fact that rhAFP and rhAFP(0) demonstrated slightly less effective tumor suppressive activity as compared to eAFP but rhAFP(0) had produced statistically notable increase in its ability to induce inhibition of in vitro lymphocyte proliferation as compared to the glycosylated rhAFP and eAFP. We conclude that N-linked glycosylation of rhAFP is required for efficient folding and secretion. However the presence of N-linked sugar moiety was shown to be unimportant for tumor suppressive activity but was critically important for its immunoregulative activity which demonstrates that different molecular mechanisms are involved in these two types of biological functional activities attributed to AFP.

Problems of the diffraction of electromagnetic waves on conducting screens of finite sizes are reduced, as a rule, to the Fredholm integral equations for the current density at both the perfect and impedance surfaces. For a perfectly conducting screen it has been shown that the scattered field can be presented by a stationary functional with respect to the surface current density. It provides a method for an approximate consideration of the problem eliminating the stage of direct solution of equations. The validity of the variational approach for the case of an impedance screen is shown. The stationary expression for the diffraction field is derived.

The influence of diffraction effects on microwave emission of local objects can be of interest in the problems of remote sensing by passive methods. It is known that the theoretical analysis of similar problems reduces to finding out the diffraction characteristics on these objects. The aim of this paper is to research the diffraction characteristics of electromagnetic waves of a slit structure and to obtain expressions for antenna temperature and emissivity. In this connection a rigorous solution of the diffraction problem of cylindrical electromagnetic waves by an infinite slit in a plane impedance screen is presented. The electromagnetic field of the incident wave is formed by an electric current sheet situated in the far zone of the free half space. Integral equations of the problem are solved by the projection (Galerkin's) method.

KEDR is a general-purpose detector for experiments at the VEPP-4M e + e − -collider in the energy range 2 E =2.0– 12 GeV . All detector subsystems (except the aerogel Cherenkov counters) have been installed into the detector at VEPP-4M. Some preliminary data have been taken in the energy region of the J/Ψ meson. The tuning of the detector and the VEPP-4M collider is in progress. Preliminary results on the detector performance are presented. The future experimental program for the KEDR detector is discussed.