6,412 research outputs found

    Morpho-functional basis of endothelial dysfunction in diabetes mellitus

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    The diabetes mellitus (DM) inevitably progresses and leads to complications, among which the main place is occupied by micro- and macroangiopathies. The presence of endothelial damage in DM can be established even before macroscopically significant damage to the vessel. At the same time, there is no summary ED characteristic for diabetes. The aim of the study is to make a comprehensive evaluation of ED in DM -1 and DM-2 types.Materials and methods of research. 60 persons, including 53 DM type 1 and type 2, with a severe course (state of decompensation) participated in the present study. We used the method of estimating ED by the number of circulating desquamation endothelial cells (CECs) at the stages of decomposition with simultaneous determination of NO2- and NO3- metabolites of nitric oxide.Results and discussion. In patients with diabetes, the level of CECs increased in 3-5 times and ranged from 1800 to 11,200 cells / ml. The average amount of CECs in patients with diabetes was 3358.5 ± 366.3 cells / ml.Conclusions: Endothelium is involved in the pathological process at DM. This is evidenced by a significant increase in CECs in the blood plasma. The use of this method allows to detect ED before clinically considerable vascular impairment and reflects the severity of the course and duration of DM

    Endothelial dysfunction in patients after COVID-19

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    Relevance: Over the past two years, the COVID-19 infection has gained unprecedented relevance at the global level. All countries are spending significant resources in the fight against COVID-19 [1 2]. The purpose of the work is to clarify the issue of the state of the kidneys in the distant post-covid period (after 2-3 months), we conducted a study of the kidneys simultaneously with the desquamation of the endothelium, as one of the probable mechanisms of the nephrotic effect of the COVID-19 virus. Materials and methods: 29 people participated in the study. Patients with post-covid syndrome (n=10) were treated on an outpatient basis at the "KNP "Center of primary medical and sanitary (medical and sanitary) care No. 3, Odesa" of the Odesa City Council" in the period from 2020 to 2021. The control group consisted of patients without cardiovascular and endocrine disorders, comparable in terms of gender and age, who were examined in 2018 at the Odesa Regional Clinical Medical Center of the Odesa Regional Council. Endothelial dysfunction "ED" was determined by the intensity of desquamation of the endothelium according to the method of J. Hladovec as modified by M.M. Petryschev. and other. (2001).           Statistical analysis was performed using Status software [https://status-please.herokuapp.com/]. Mean values ​​(M) and its standard deviation (SD) were used to describe quantitative data, and percentages were used for qualitative data. For comparison, data were presented as M and standard error of the mean (SEM). Analysis of normality was performed using the Shapiro-Wilk test. Levene's test was used to assess homogeneity of variances. Differences between groups were determined using Student's t-test and one-way analysis of variance (ANOVA). The relationship and presence of correlation between the studied parameters was determined using the Pearson correlation coefficient (r). The correlation coefficient in the range of 0.5≤|r|<1 indicated a strong correlation relationship, 0.3≤|r|<0.5 – a relationship of medium strength, 0<|r|<0.3 – on a weak correlation. Statistical significance was established only at the level of p < 0.05. Results: 17 men and 12 women aged from 32 to 80 years who suffered from a disease of moderate severity participated in the study. The average age of the group of patients with post-covid syndrome (n=9) is 55.9±14.47 years, the average age of the control group (n=20) is 55.95±14.47 years. There were no complaints from the urinary system in the examined patients. According to blood serum tests, it was established that the creatinine level among patients with post-covid syndrome was on average 113±11.91 μmol/l, the urea level was 8.11±1.2 mmol/l, the GFR level was 55.06±12, 19 ml/min/1.73. m2. In the control group, the numbers were as follows: creatinine level was 73.2±8.5 μmol/l, mean urea level was 4.61 mmol/l, GFR was 94.78±13.76 ml/min/1.73 m2. Conclusions: 2-3 months after the transfer of COVID-19, the examined patients show signs of chronic kidney disease. After a disease with COVID-19, an increase in CEC is detected, which is a manifestation of endothelial dysfunction

    Engineering chiral spin interactions with Rydberg atoms

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    We propose to simulate the anisotropic and chiral Dzyaloshinskii-Moriya (DM) interaction with Rydberg atom arrays. The DM Hamiltonian is engineered in a one-dimensional optical lattice or trap array with effective long-range Rydberg spins, interacting indirectly via a mobile mediator Rydberg atom. A host of XXZ and DM Hamiltonians can be simulated with out-of-phase sign periodic coupling strengths; for initial states in a stationary condensate, the DM interaction vanishes. This theory allows for determination of the DM interaction (DMI) vector components from first principles. The inherent anisotropy of the Rydberg-Rydberg interactions, facilitates the DMI coupling to be tuned so as to be comparable to the XXZ interaction. Our results make plausible the formation of non-trivial topological spin textures with Rydberg atom arrays.Comment: 4 pages, 2 figure

    On Supergroups with Odd Clifford Parameters and Supersymmetry with Modified Leibniz Rule

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    We investigate supergroups with Grassmann parameters replaced by odd Clifford parameters. The connection with non-anticommutative supersymmetry is discussed. A Berezin-like calculus for odd Clifford variables is introduced. Fermionic covariant derivatives for supergroups with odd Clifford variables are derived. Applications to supersymmetric quantum mechanics are made. Deformations of the original supersymmetric theories are encountered when the fermionic covariant derivatives do not obey the graded Leibniz property. The simplest non-trivial example is given by the N=2 SQM with a real (1,2,1)(1,2,1) multiplet and a cubic potential. The action is real. Depending on the overall sign ("Euclidean" or "Lorentzian") of the deformation, a Bender-Boettcher pseudo-hermitian hamiltonian is encountered when solving the equation of motion of the auxiliary field. A possible connection of our framework with the Drinfeld twist deformation of supersymmetry is pointed out.Comment: Final version to be published in Int. J. Mod. Phys. A; 20 page

    New Insights into Dissipation in the Electron Layer During Magnetic Reconnection

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    Detailed comparisons are reported between laboratory observations of electron-scale dissipation layers near a reconnecting X-line and direct two-dimensional full-particle simulations. Many experimental features of the electron layers, such as insensitivity to the ion mass, are reproduced by the simulations; the layer thickness, however, is about 3-5 times larger than the predictions. Consequently, the leading candidate 2D mechanism based on collisionless electron nongyrotropic pressure is insufficient to explain the observed reconnection rates. These results suggest that, in addition to the residual collisions, 3D effects play an important role in electron-scale dissipation during fast reconnection.Comment: 17 pages, 4 figure

    Heavy Flavor Hadrons in Statistical Hadronization of Strangeness-rich QGP

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    We study b, c quark hadronization from QGP. We obtain the yields of charm and bottom flavored hadrons within the statistical hadronization model. The important novel feature of this study is that we take into account the high strangeness and entropy content of QGP, conserving strangeness and entropy yields at hadronization.Comment: v2 expended: 20 pages, 23 figures, 5 tables, in press EPJ-

    The sl(2n|2n)^(1) Super-Toda Lattices and the Heavenly Equations as Continuum Limit

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    The nn\to\infty continuum limit of super-Toda models associated with the affine sl(2n2n)(1)sl(2n|2n)^{(1)} (super)algebra series produces (2+1)(2+1)-dimensional integrable equations in the S1×R2{\bf S}^{1}\times {\bf R}^2 spacetimes. The equations of motion of the (super)Toda hierarchies depend not only on the chosen (super)algebras but also on the specific presentation of their Cartan matrices. Four distinct series of integrable hierarchies in relation with symmetric-versus-antisymmetric, null-versus-nonnull presentations of the corresponding Cartan matrices are investigated. In the continuum limit we derive four classes of integrable equations of heavenly type, generalizing the results previously obtained in the literature. The systems are manifestly N=1 supersymmetric and, for specific choices of the Cartan matrix preserving the complex structure, admit a hidden N=2 supersymmetry. The coset reduction of the (super)-heavenly equation to the I×R(2)=(S1/Z2)×R2{\bf I}\times{\bf R}^{(2)}=({\bf S}^{1}/{\bf Z}_2)\times {\bf R}^2 spacetime (with I{\bf I} a line segment) is illustrated. Finally, integrable N=2,4N=2,4 supersymmetrically extended models in (1+1)(1+1) dimensions are constructed through dimensional reduction of the previous systems.Comment: 12 page

    Modeling the spectrum of V4334 Sgr (Sakurai's Object)

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    Theoretical spectral energy distributions were computed for a grid of hydrogen-deficient and carbon-rich model atmospheres of T(eff) in the range of 5000-6250 K and log g = 1.0 - 0.0 by the technique of opacity sampling, taking into account continuous, molecular band and atomic line absorption. These energy distributions were compared with the spectrum of V4334 Sgr (Sakurai's object) of April, 1997 in the wavelength interval 300-1000 nm. We show that (1) the shape of the theoretical spectra depends strongly on T(eff) but only very weakly on the hydrogen abundance; (2) the comparison of the observed and computed spectra permits to estimate T(eff) approximately 5500 K for V4334 Sgr in April, 1997, and its interstellar reddening (plus a possible circumstellar contribution) E(B-V) approximately 0.70.Comment: 7 pages, 8 figures, LaTeX, accepted by Astronomy and Astrophysic

    Improved dd+4^4He potentials by inversion, the tensor force and validity of the double folding model

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    Improved potential solutions are presented for the inverse scattering problem for dd+4^4He data. The input for the inversions includes both the data of recent phase shift analyses and phase shifts from RGM coupled-channel calculations based on the NN Minnesota force. The combined calculations provide a more reliable estimate of the odd-even splitting of the potentials than previously found, suggesting a rather moderate role for this splitting in deuteron-nucleus scattering generally. The approximate parity-independence of the deuteron optical potentials is shown to arise from the nontrivial interference between antisymmetrization and channel coupling to the deuteron breakup channels. A further comparison of the empirical potentials established here and the double folding potential derived from the M3Y effective NN force (with the appropriate normalisation factor) reveals strong similarities. This result supports the application of the double folding model, combined with a small Majorana component, to the description even of such a loosely bound projectile as the deuteron. In turn, support is given for the application of iterative-perturbative inversion in combination with the double folding model to study fine details of the nucleus-nucleus potential. A dd-4^4He tensor potential is also derived to reproduce correctly the negative 6^6Li quadrupole moment and the D-state asymptotic constant.Comment: 22 pages, 12 figures, in Revte

    Symmetries of Electrostatic Interaction between DNA Molecules

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    We study a model for pair interaction UU of DNA molecules generated by the discrete dipole moments of base-pairs and the charges of phosphate groups, and find noncommutative group of eighth order S{\cal S} of symmetries that leave UU invariant. We classify the minima using group S{\cal S} and employ numerical methods for finding them. The minima may correspond to several cholesteric phases, as well as phases formed by cross-like conformations of molecules at an angle close to 90o\rm{90}^{o}, "snowflake phase". The results depend on the effective charge QQ of the phosphate group which can be modified by the polycations or the ions of metals. The snowflake phase could exist for QQ above the threshold QCQ_C. Below QCQ_C there could be several cholesteric phases. Close to QCQ_C the snowflake phase could change into the cholesteric one at constant distance between adjacent molecules.Comment: 13 pages, 4 figure
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