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Level of 25-Hydroxyvitamin D in Pediatric Arthritis Patients

Abstract

Vitamin D deficiency is common and widespread globally. Vitamin D has an immunomodulatory effect, but it is still unclear whether its deficiency is associated with higher disease activity. The aim of this retrospective study was to determine the serum concentration of vitamin D in children with paediatric arthritis (juvenile idiopathic arthritis and reactive arthritis). Prevalence of hypo-vitaminosis D among 98 children with juvenile idiopathic arthritis and reactive arthritis was determined and association between serum concentration of vitamin D and disease activity markers was found. Prevalence of vitamin D deficiency among children included in this study was 69.07%. Children with juvenile idiopathic arthritis had a significantly lower vitamin D level than children with reactive arthritis. There was a statistically significant moderate negative correlation between serum concentration of vitamin D and patient age, as well as a weak negative correlation between vitamin D level and patient body mass index. The significant correlations found between vitamin D level and inflammatory markers indicate that further research on the role of vitamin D in disease activity is needed.

Open access
Multidimensional BSDE with Poisson jumps of Osgood type

Abstract

This paper is devoted to solve a multidimensional backward stochastic differential equation with jumps in finite time horizon. Under linear growth generator, we prove existence and uniqueness of solution.

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Retrospective Data Analysis of Anterior Cervical Discectomies and Fusion Without Plate and Screws

Abstract

Surgical intervention in cervical disease can relieve neurological symptoms and improve life quality. This study aimed to analyse retrospective data of microscope-assisted anterior cervical discectomy and fusion (ACDF) surgeries. The retrospective study was carried out at the ORTO clinic, Rīga, Latvia, from 2013 to 2017. Data from 198 patients were extracted retrospectively. Data on patient gender, age, diagnosis, extent of operation, type of cage and the overall height of the implants were used. Comparative analysis was carried out with the SPSS 22 software. P < 0.05 represented statistical significance. During the study period, 198 elective ACDF were carried out with increasing number of surgeries: 25 cases in 2013, 43 in 2014, 38 in 2015, 44 in 2016, and 48 in 2017. ACDF were significantly more often performed for females (n = 117, 59%) compared to males (n = 81, 41%; p < 0.003). Women were older with an average age of 50 ± 1 years than men (age 46 ± 1; p = 0.007). The mean surgery time was 1.5 ± 1 hours and the mean hospitalisation time was 3 ± 1 days. Four types of cages were used in similar number of operation: Cervios Peek Chronos C (24%), Syncage C (21%), EIT 3D print (29%), Cervios C Peek (26%); p = 0.2, regardless of patient age or gender. Most often, in 98 cases, the overall height of implants was 6–10 mm. The maximal height was 22 mm, where two patients underwent three-level, and one had a four-level discectomy. The most prevalent disc lesion levels were C5/6 and C6/7, followed by C4/5 and C3/4. One- and two-level discectomies were performed in similar numbers: 95 and 81 cases. However, only 20 patients underwent three level and two patients had four level discectomies in 2016 and 2017. Two level discectomy at C5/6, C6/7 was carried out significantly more often for women (55 vs. 26; p = 0.01), and for men 1-level lesion was more common in C6/7; p = 0.04. The overall incidence of cage subsidence was 5.5%, and the highest incidence was 24% when a Syncage C was used. The ACDF appears to be performed increasingly more often, particularly, in females. The most frequent operation was in one or two cervical levels; including level C6/7 in both genders. In the last years, three- and four-level cervical discectomies have become one of the surgical opportunities. Choice of cage was not influenced by patient gender and age, while cage biophysical and biochemical properties may influence the choice.

Open access
Stochastic Modelling for Dynamics of Interacting Populations

Abstract

The paper deals with a mathematical model for two interacting populations. Under the assumption of fast stochastic contacting of populations, we derive stochastic Poisson-type differential equations with a small parameter and propose an approximative algorithm for quantitative analysis of population dynamics that consists of two steps. First, we derive an ordinary differential equation for mean value of each population growth and analyse the average asymptotic population behaviour. Then, applying diffusion approximation procedure, we derive a stochastic Ito differential equation for small random deviations on the average motion in a form of a linear non-homogeneous Ito stochastic differential equation and analyse the probabilistic characteristics of the Gaussian process given by this equation.

Open access
Validation of Bread Wheat KASP Markers in Durum Wheat Lines in Kazakhstan

Abstract

Development of efficient DNA markers plays an important role in modern breeding projects of many crops, including cultivated hexaploid bread wheat (BW) and tetraploid durum wheat (DW). Findings of genome-wide association studies on major polyploid crops, such as BW, may also help in molecular breeding studies in relative cultivated species with a similar genetic background, including DW. Therefore, the validation of identified quantitative trait loci or marker-trait associations is an important preliminary step in marker-assisted selection (MAS) oriented projects. In this study, thirty-two SNP (single nucleotide polymorphism) markers of six agronomic traits identified in BW, harvested in Kazakhstan, were converted to KASP (Kompetitive Allele-Specific PCR) as-says. Generated 32 KASP assays were used in the analysis of 29 DW accessions from Kazakhstan. Firstly, the group of DW accessions was tested using replicated and randomised one-metre blocks in field conditions of southeast Kazakhstan and evaluated for main agronomic traits. The analysis showed that 14 KASP assays were polymorphic in the scoring of 29 DW accessions. The t-test suggested that the segregation in eight KASP assays was significantly associated with five agronomic traits. The study confirms robustness of KASP assays in MAS of DW breeding projects for the improvement of yield potential.

Open access
QSPR Analysis of certain Distance Based Topological Indices

Abstract

In QSAR/QSPR study, topological indices are utilized to guess the bioactivity of chemical compounds. In this paper, we study the QSPR analysis of selected distance and degree-distance based topological indices. Our study reveals some important results which help us to characterize the useful topological indices based on their predicting power.

Open access
The 5-Way Scale

Abstract

In this paper, we discuss coin-weighing problems that use a 5-way scale which has five different possible outcomes: MUCH LESS, LESS, EQUAL, MORE, and MUCH MORE. The 5-way scale provides more information than the regular 3-way scale. We study the problem of finding two fake coins from a pile of identically looking coins in a minimal number of weighings using a 5-way scale. We discuss similarities and differences between the 5-way and 3-way scale. We introduce a strategy for a 5-way scale that can find both counterfeit coins among 2k coins in k + 1 weighings, which is better than any strategy for a 3-way scale.

Open access
Applications of Stochastic Semigroups to Queueing Models

Abstract

Non-markovian queueing systems can be extended to piecewise-deterministic Markov processes by appending supplementary variables to the system. Then their analysis leads to an infinite system of partial differential equations with an infinite number of variables and non-local boundary conditions. We show how one can study such systems by using the theory of stochastic semigroups.

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Approximate Analytical Solutions to Conformable Modified Burgers Equation Using Homotopy Analysis Method

Abstract

In this paper the authors aspire to obtain the approximate analytical solution of Modified Burgers Equation with newly defined conformable derivative by employing homotopy analysis method (HAM).

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Complex Gleason Measures and the Nemytsky Operator

Abstract

This work is devoted to the generalization of previous results on Gleason measures to complex Gleason measures. We develop a functional calculus for complex measures in relation to the Nemytsky operator. Furthermore we present and discuss the interpretation of our results with applications in the field of quantum mechanics. Some concrete examples and further extensions of several theorems are also presented.

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