Determination of the UV cut-off from the observed value of the Universe acceleration

It is shown that using of the equation of motion of the Universe scale factor allows calculation of the contribution of the vacuum fluctuations to the acceleration of the Universe expansion. Renormalization of the equation is needed only in the case of massive particles. Under a known number of the different kinds of fundamental fields, this provides determination of momentum of the ultraviolet cut-off from the observed value of acceleration.Comment: 10 pages, 1 figur

КВАЗИКРИСТАЛЛИЧЕСКАЯ МОДЕЛЬ РАДИАЛЬНОЙ ФУНКЦИИ РАСПРЕДЕЛЕНИЯ ТВЕРДЫХ ДИСКОВ НА ПЛОСКОСТИ

The quasi-crystal model of the radial distribution function for hard disks in the plane is suggested. It is shown that the coincidence with the distribution function, obtained by solving Percus–Yevick’s equation, is found by smoothing a square lattice and injecting vacancy-type defects into it. A better approximation is reached when the lattice is a result of a mixture of smoothened square and hexagonal lattices. Impurity of a hexagonal lattice is considerable at short distances. Dependences of lattice constants, smoothing widths and impurity on the filling parameter are found. In conclusion, it is stated that a basis of such a chaotic system apparently as a gas of hard disks in the plane at rather small filling parameters is a square lattice with some impurity of the hexagonal lattice at small distances. It is of importance to carry out investigations in a range of higher concentration and to compare with the modeling by the Monte-Carlo method. В рамках квазикристаллической модели предложен новый метод описания радиальной функции распределения твердых дисков на плоскости. Радиальная функция распределения моделируется размазыванием квадратной решетки и образованием дефектов типа вакансий. Наилучшие совпадения с радиальной функцией распределения, полученной решением интегрального уравнения Перкуса–Йевика, достигается в результате использования суперпозиции квадратной и гексагональной решеток. Примесь гексагональной решетки существенна на малых расстояниях. Найдены зависимости постоянной решетки, ширины размывания, примеси гексагональной решетки от параметра заполнения. Предполагается, что данный метод будет работать и области более высоких плотностей, где он может быть использован для описания перехода из жидкой фазы в гексатическую и затем в кристаллическую.

Laser in the axial electric field as a tool to search for P-, T- invariance violation

We consider rotation of polarization plane of the laser light when a gas laser is placed in a longitudinal electric field (10~kV/cm). It is shown that residual anisotropy of the laser cavity 10^{-6} and the sensitivity to the angle of polarization plane rotation about 10^{-11} -10^{-12} rad allows one to measure an electron EDM with the sensitivity about 10^{-30} e cm.Comment: 12 page

Entrepreneurial Behaviour and Organisational Propensity to Innovate in a Public Sector Context

The importance of innovation, in both private and public entrepreneurial fields, is the basis of all companies’ strategic choices. This study examines entrepreneurship and innovation, as well as their dynamic interface in value creation, in the public sector. It explores entrepreneurial determinants for public sector innovation, as collected from managers and employees involved in the water supply and sewage industries in Ukraine. The data, related to a sample of firms, were obtained from a twofold self-administered survey. Adopting an ordered logistic regression model to analyse the data obtained from a survey, it is discovered that the entrepreneurial determinants of self-awareness, knowledge-enabling and entrepreneurial orientation positively correlate with fostering innovation process. The findings reveal that entrepreneurial leadership and intrapreneurial self-efficacy are mediating determinants. Finally, the results demonstrate that intrapreneurial self-efficacy has more potential than entrepreneurial leadership to stimulate innovation at the individual level, which has both theoretical and practical implications

Gut microbiota and carcinogenesis: actual aspects

The microbiota, together with the host, form a symbiotic relationship in which the microbiota plays a key role in maintaining the homeostasis of the human body, performing a number of significant functions such as energy metabolism, maturation and maintenance of the immune system, vitamin synthesis, regulation of bile acid reabsorption in the intestine, and much more. Scientific research in recent years has made a significant contribution to understanding the complex relationship between the microbiota and a range of human pathologies, including malignant neoplasms. The review considers the mechanisms of the possible influence of bacteria on the development and progression of cancer with an emphasis on the procarcinogenic properties of the microbiota. The most important factor in the mechanism of influence of the microbiota on carcinogenesis are toxins produced by microorganisms that induce direct damage to host cell DNA, causing DNA mutations, disruption of its exact replication, and also provoke an imbalance in the proliferation and apoptosis of host cells, their rapid aging and oncogenesis. The probable mechanisms of participation of microorganisms in the development of cancer through the activation of TLRs and NLRs receptors, which have a tumor-activating effect, are considered. A brief review is given on the mechanisms of carcinogenesis associated with the metabolic activity of the microbiota due to the processes of regulation of the production of secondary bile acids, activation of pro-carcinogenic compounds: phenols, ethanol, sulfides, ammonia, nitrosamines. The influence of the microbiota on the metabolism of sex hormones and the development of hormone-dependent cancers mediated by the mechanisms of enterohepatic circulation and estrogen deconjugation is described. The study of the carcinogenic mechanisms of action of the microbiota in the host organism opens up prospects for the development of new successful personalized approaches to the diagnosis, treatment, and prevention of cancer. Changing the composition of the microbiota should become a way to fight cancer, along with surgical treatment, chemotherapy, radiation therapy, targeted therapy and immunotherapy

Testing of CP, CPT and causality violation with the light propagation in vacuum in presence of the uniform electric and magnetic fields

We have considered the structure of the fundamental symmetry violating part of the photon refractive index in vacuum in the presence of constant electric and magnetic fields. This part of the refractive index can, in principle, contain CPT symmetry breaking terms. Some of the terms violate Lorentz invariance, whereas the others violate locality and causality. Estimates of these effects, using laser experiments are considered.Comment: 12 page

Serotonin 5-HT4 receptor boosts functional maturation of dendritic spines via RhoA-dependent control of F-actin

Activity-dependent remodeling of excitatory connections underpins memory formation in the brain. Serotonin receptors are known to contribute to such remodeling, yet the underlying molecular machinery remains poorly understood. Here, we employ high-resolution time-lapse FRET imaging in neuroblastoma cells and neuronal dendrites to establish that activation of serotonin receptor 5-HT4 (5-HT4R) rapidly triggers spatially-restricted RhoA activity and G13-mediated phosphorylation of cofilin, thus locally boosting the filamentous actin fraction. In neuroblastoma cells, this leads to cell rounding and neurite retraction. In hippocampal neurons in situ, 5-HT4R-mediated RhoA activation triggers maturation of dendritic spines. This is paralleled by RhoA-dependent, transient alterations in cell excitability, as reflected by increased spontaneous synaptic activity, apparent shunting of evoked synaptic responses, and enhanced long-term potentiation of excitatory transmission. The 5-HT4R/G13/RhoA signaling thus emerges as a previously unrecognized molecular pathway underpinning use-dependent functional remodeling of excitatory synaptic connections

Secretory phospholipase A2: a biomarker of inflammation in autoimmune, bacterial and viral diseases

Secretory phospholipases A2 (sPLA2) represent a large superfamily of enzymes with a molecular weight of 14-19 kDa, including 15 groups and more than 30 isoforms belonging to four types: secretory (sPLA2), cytosolic (cPLA2), calcium-independent (iPLA2) and lipoprotein-associated phospholipase A2 (LP-PLA2, PAF-AH). Eleven species of secretory sPLA2s (IB, IIA, IIC, IID, IIE, IIF, III, V, X, XIIA, and XIIB) have been found in mammals, performing versatile functions and participating in the pathogenesis of a wide range of diseases. On the one hand, sPLA2 may promote elimination of damaged, apoptotic cells by hydrolyzing membrane phospholipids, and exerts a strong bactericidal and antiviral properties, including pronounced effects against antibiotic-resistant strains of microorganisms. In this regard, the use of sPLA2 may represent a new strategy for the treatment of bacterial and viral infections. Moreover, due to the action of sPLA2 on its substrates, a number of biologically active molecules (arachidonic, lysophosphatidic acids, lysophospholipids, fatty acids, prostaglandins, leukotrienes, thromboxanes) are formed, which provide strong inflammatory, detergent, coagulating effects and increase vascular permeability. This pro-inflammatory role of sPLA2 may explain its increase levels and activity in cardiovascular, respiratory, autoimmune, metabolic, oncological, bacterial and viral disorders. The review article presents a classification of sPLA2 isoforms, their substrates, regulatory factors, biological significance, and mechanisms of their strong bactericidal, virucidal, and pro-inflammatory activity in the heart and lung disorders, autoimmune, metabolic, bacterial, and viral diseases. In particular, the mechanisms of the selective action of sPLA2 against Gram-positive and Gram-negative microorganisms are discussed. We consider diagnostic and prognostic significance, correlations between elevated levels and activity of sPLA2 and distinct clinical symptoms, severity and outcome in the patients with coronary heart disease (CAD), acute myocardial infarction (AMI), atherosclerosis, acute inflammatory lung injury (ALI), respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, bronchial asthma, bacterial infections, septicemia and viral (COVID-19) infections. The opportunity of using sPLA2 as a biomarker of the severity and outcome of patients with chronic obstructive pulmonary disease, bacterial infections, sepsis and viral infections, including COVID-19, is also considered

Genome-wide association scan meta-analysis identifies three Loci influencing adiposity and fat distribution.

To identify genetic loci influencing central obesity and fat distribution, we performed a meta-analysis of 16 genome-wide association studies (GWAS, N = 38,580) informative for adult waist circumference (WC) and waist-hip ratio (WHR). We selected 26 SNPs for follow-up, for which the evidence of association with measures of central adiposity (WC and/or WHR) was strong and disproportionate to that for overall adiposity or height. Follow-up studies in a maximum of 70,689 individuals identified two loci strongly associated with measures of central adiposity; these map near TFAP2B (WC, P = 1.9x10(-11)) and MSRA (WC, P = 8.9x10(-9)). A third locus, near LYPLAL1, was associated with WHR in women only (P = 2.6x10(-8)). The variants near TFAP2B appear to influence central adiposity through an effect on overall obesity/fat-mass, whereas LYPLAL1 displays a strong female-only association with fat distribution. By focusing on anthropometric measures of central obesity and fat distribution, we have identified three loci implicated in the regulation of human adiposity