On Poisson–Tweedie mixtures

Poisson-Tweedie mixtures are the Poisson mixtures for which the mixing measure is generated by those members of the family of Tweedie distributions whose support is non-negative. This class of non-negative integer-valued distributions is comprised of Neyman type A, back-shifted negative binomial, compound Poisson-negative binomial, discrete stable and exponentially tilted discrete stable laws. For a specific value of the “power” parameter associated with the corresponding Tweedie distributions, such mixtures comprise an additive exponential dispersion model. We derive closed-form expressions for the related variance functions in terms of the exponential tilting invariants and particular special functions. We compare specific Poisson-Tweedie models with the corresponding Hinde-Demétrio exponential dispersion models which possess a comparable unit variance function. We construct numerous local approximations for specific subclasses of Poisson-Tweedie mixtures and identify Lévy measure for all the members of this three-parameter family

The evaluation of a weighted sum of Gauss hypergeometric functions and its connection with Galton–Watson processes

We evaluate a weighted sum of Gauss hypergeometric functions for certain ranges of the argument, weights and parameters. We establish the domain of absolute convergence of this series by determining the growth of the hypergeometric function for large summation index. We present an application to Galton–Watson branching processes arising in the theory of stochastic processes. We introduce a new class of positive integer-valued distributions with power tails

Regional geographic information systems of health and environmental monitoring

The article describes a new scientific and methodological approach to designing geographic information systems of health and environmental monitoring for urban areas. Geographic information systems (GIS) are analytical tools of the regional health and environmental monitoring; they are used for an integrated assessment of the environmental status of a large industrial centre or a part of it. The authors analyse the environmental situation in Voronezh, a major industrial city, located in the Central Black Earth Region with a population of more than 1 million people. The proposed research methodology is based on modern approaches to the assessment of health risks caused by adverse environmental conditions. The research work was implemented using a GIS and multicriteria probabilistic and statistical evaluation to identify cause-and-effect links, a combination of action and reaction, in the dichotomy "environmental factors - public health". The analysis of the obtained statistical data confirmed an increase in childhood diseases in some areas of the city. Environmentally induced diseases include congenital malformations, tumors, endocrine and urogenital pathologies. The main factors having an adverse impact on health are emissions of carcinogens into the atmosphere and the negative impact of transport on the environment. The authors identify and characterize environmentally vulnerable parts of the city and developed principles of creating an automated system of health monitoring and control of environmental risks. The article offers a number of measures aimed at the reduction of environmental risks, better protection of public health and a more efficient environmental monitoring

Femtosecond and Ultraviolet Laser Irradiation of Graphite-Like Hexagonal Boron Nitride

Effect of the femtosecond and nanosecond UV laser irradiation (below the ablation threshold) of graphite-like hexagonal boron nitride (hBN) has been studied. Experiments were carried out with the compacted powder under high vacuum at room temperature using excimer KrF laser (248 nm). In the nanosecond operation mode, the laser-induced fluorescence spectra are found strongly modified depending on the integrated doze, which is attributed to a progressive enrichment of the surface layer by elemental boron. A slow sample recovery after the laser irradiation has been observed. On the other hand, in the femtosecond mode the fluorescence spectra depend on the laser fluence, and the changes are reversible: low energy fluorescence spectra are restored immediately when the laser energy decreases. This effect can be explained by a material bleaching, which favors a bulk centers emission. The ablation threshold has been determined as 78 mJ/cm2 in the femtosecond laser operational mode

Anemia and quality of life of chronic kidney disease patients on renal replacement therapy by programmed hemodialysis

Aim. To study relationship between anemia and health-related quality of life (HRQOL) of chronic kidney disease stage 5 patients (CKD) undergoing renal replacement therapy by programmed hemodialysis. Materials and Methods. The study was conducted on the basis of dialysis centers/departments in Moscow. The Russian-language version of the KDQOL-SFTM questionnaire, validated in Russia, was used to assess the HRQOL of patients on hemodialysis. A total of 723 patients were interviewed. Hemoglobin (Hb) levels were assessed in 442 patients based on outpatient records. To identify the relationship between Hb level and HRQOL scales, a correlation analysis was performed, as well as a HRQOL analysis in the three groups differing in hemoglobin levels (100; 100-120 and 120 g/l). Statistical data processing was carried by SPSS.22 and using parametric and nonparametric statistical methods. Results. Correlation relationship was revealed between Hb and HRQOL of patients on hemodialysis on the scales "symptoms/problems", "pain", "vital activity, energy" and "total physical component of health". According to the scales "symptoms/problems" and "vital activity, energy", higher rates were noted among patients with Hb higher than the target level, which confirms the recommendations concerning the possibility of achieving higher Hb among individual patients who have not serious concomitant diseases and cardiovascular complications in order to improve their quality of life. Conclusion. HRQOL assessment is important tool for planning and evaluating the effectiveness of anemia drug therapy among patients with CKD on hemodialysis

Isolation and Characterization of Human Colon Adenocarcinoma Stem-Like Cells Based on the Endogenous Expression of the Stem Markers.

BACKGROUND: Cancer stem cells\u27 (CSCs) self-maintenance is regulated via the pluripotency pathways promoting the most aggressive tumor phenotype. This study aimed to use the activity of these pathways for the CSCs\u27 subpopulation enrichment and separating cells characterized by the OCT4 and SOX2 expression. METHODS: To select and analyze CSCs, we used the SORE6x lentiviral reporter plasmid for viral transduction of colon adenocarcinoma cells. Additionally, we assessed cell chemoresistance, clonogenic, invasive and migratory activity and the data of mRNA-seq and intrinsic disorder predisposition protein analysis (IDPPA). RESULTS: We obtained the line of CSC-like cells selected on the basis of the expression of the OCT4 and SOX2 stem cell factors. The enriched CSC-like subpopulation had increased chemoresistance as well as clonogenic and migration activities. The bioinformatic analysis of mRNA seq data identified the up-regulation of pluripotency, development, drug resistance and phototransduction pathways, and the downregulation of pathways related to proliferation, cell cycle, aging, and differentiation. IDPPA indicated that CSC-like cells are predisposed to increased intrinsic protein disorder. CONCLUSION: The use of the SORE6x reporter construct for CSCs enrichment allows us to obtain CSC-like population that can be used as a model to search for the new prognostic factors and potential therapeutic targets for colon cancer treatment

Generalizations of Nonlinear and Supersymmetric Classical Electrodynamics

We first write down a very general description of nonlinear classical electrodynamics, making use of generalized constitutive equations and constitutive tensors. Our approach includes non-Lagrangian as well as Lagrangian theories, allows for electromagnetic fields in the widest possible variety of media (anisotropic, piroelectric, chiral and ferromagnetic), and accommodates the incorporation of nonlocal effects. We formulate electric-magnetic duality in terms of the constitutive tensors. We then propose a supersymmetric version of the general constitutive equations, in a superfield approach.Comment: 15 pages, based on the presentation by G. A. Goldin at QTS

Enhanced presentation of MHC class Ia, Ib and class II-restricted peptides encapsulated in biodegradable nanoparticles: a promising strategy for tumor immunotherapy

<p>Abstract</p> <p>Background</p> <p>Many peptide-based cancer vaccines have been tested in clinical trials with a limited success, mostly due to difficulties associated with peptide stability and delivery, resulting in inefficient antigen presentation. Therefore, the development of suitable and efficient vaccine carrier systems remains a major challenge.</p> <p>Methods</p> <p>To address this issue, we have engineered polylactic-co-glycolic acid (PLGA) nanoparticles incorporating: (i) two MHC class I-restricted clinically-relevant peptides, (ii) a MHC class II-binding peptide, and (iii) a non-classical MHC class I-binding peptide. We formulated the nanoparticles utilizing a double emulsion-solvent evaporation technique and characterized their surface morphology, size, zeta potential and peptide content. We also loaded human and murine dendritic cells (DC) with the peptide-containing nanoparticles and determined their ability to present the encapsulated peptide antigens and to induce tumor-specific cytotoxic T lymphocytes (CTL) <it>in vitro</it>.</p> <p>Results</p> <p>We confirmed that the nanoparticles are not toxic to either mouse or human dendritic cells, and do not have any effect on the DC maturation. We also demonstrated a significantly enhanced presentation of the encapsulated peptides upon internalization of the nanoparticles by DC, and confirmed that the improved peptide presentation is actually associated with more efficient generation of peptide-specific CTL and T helper cell responses.</p> <p>Conclusion</p> <p>Encapsulating antigens in PLGA nanoparticles offers unique advantages such as higher efficiency of antigen loading, prolonged presentation of the antigens, prevention of peptide degradation, specific targeting of antigens to antigen presenting cells, improved shelf life of the antigens, and easy scale up for pharmaceutical production. Therefore, these findings are highly significant to the development of synthetic vaccines, and the induction of CTL for adoptive immunotherapy.</p

Two-particle correlations in azimuthal angle and pseudorapidity in inelastic p + p interactions at the CERN Super Proton Synchrotron

Results on two-particle ΔηΔϕ correlations in inelastic p + p interactions at 20, 31, 40, 80, and 158 GeV/c are presented. The measurements were performed using the large acceptance NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The data show structures which can be attributed mainly to effects of resonance decays, momentum conservation, and quantum statistics. The results are compared with the Epos and UrQMD models.ISSN:1434-6044ISSN:1434-605