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The development of highly effective osteoplastic materials capable of providing bone tissue regeneration still remains an urgent and unresolved problem. In the presented work, an approach is proposed for the creation of biomimetic materials by the deposition of amorphous calcium phosphates on the surface of a xenogenic bone demineralized matrix under physiological conditions. Adsorption spectroscopy and scanning electron microscopy showed the efficiency of deposition of amorphous calcium phosphates on the trabeculae surface. The additional inclusion of the calcium-binding protein albumin was found to increase the efficiency of CPC adsorption on the trabeculae surface during DBM remineralization in vitro. In the model of heterotopic implantation for 7 weeks the osteoinductive properties of the obtained material were demonstrated, expressed in intrabecular mineralization of bone trabeculae, neovascularization and pronounced synthetic activity of osteoblasts (synthesis and structurization of neocollagen directly on the implanted material). The data obtained in the course of this work will be used to create new highly effective osteoplastic materials.

Dental cement materials have been developed with the aim to replace hard dental tissues. The first material used for pulp capping, root canal obturation, bifurcation perforation and apexification is calcium hydroxide (in 1920). A half century later, glass-ionomer cements began to suppress it as dentine substitutes. Finally, in the 1990s, calcium silicate (CS) material appeared in the dental research community as the most promising dentine substitute capable to adequately meet all clinical requirements. The aim of this paper is to present an overview of literature related to studies about CS materials taking into account their physical, chemical and biological properties and clinical applications. This review aims to discuss beneficial and adverse characteristics of CSs concerning interactions to the hard dentine and soft pulp/periodontal tissues. This review article deals with the literature data about currently commercially available CS concerning laboratory and clinical findings. 109 scientific articles were analyzed of which 62 references reported in vitro and 26 in vivo investigations while 21 references comprised reports, reviews and books dealing with both, in vitro and in vivo investigations. Although further data collection is necessary, CSs are promising materials that represent a gold standard for numerous dental clinical procedures. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172026 and Grant no. III 45005]

The article contains the results of theoretical studies of one of the parameters of the geometric image of the feeder cutter of a rotary snow blower — the angle of inclination of the cutting strip of the vertical feeder, relative to the radius of the vertical cutter. The work contains not only recommendations on rational values of the angle of inclination of the feeder cutting strip, but also presents some specific values of the width of the feeder cutting strip, at which the working process of a rotary snow blower can be considered most effective. A calculation scheme for determining the angle of inclination of a vertical cutter has been compiled. The article presents the types of interaction of a vertical cutting strip with a snow massif. Key types of interaction are presented schematically. The dependences of the angle of inclination of the tangent to the cutting path as a function of the angle of rotation relative to the radius of the cutter were obtained. Conclusions are drawn about the dependence of the angle of inclination of the cutting strip on the angle of rotation of the cutter. Several periodically repeating sections during the operation of a rotary snow blower have been identified and presented, which indicates the presence of patterns in this process. The functional dependences of the geometric dimensions of the cutting strip of a rotary snow blower on the angle of inclination of the vertical cutting strip and the angle of rotation of the vertical cutter are determined.

Simulation is a key tool in population genetics for both methods development and empirical research, but producing simulations that recapitulate the main features of genomic datasets remains a major obstacle. Today, more realistic simulations are possible thanks to large increases in the quantity and quality of available genetic data, and the sophistication of inference and simulation software. However, implementing these simulations still requires substantial time and specialized knowledge. These challenges are especially pronounced for simulating genomes for species that are not well-studied, since it is not always clear what information is required to produce simulations with a level of realism sufficient to confidently answer a given question. The community-developed framework stdpopsim seeks to lower this barrier by facilitating the simulation of complex population genetic models using up-to-date information. The initial version of stdpopsim focused on establishing this framework using six well-characterized model species (Adrion et al., 2020). Here, we report on major improvements made in the new release of stdpopsim (version 0.2), which includes a significant expansion of the species catalog and substantial additions to simulation capabilities. Features added to improve the realism of the simulated genomes include non-crossover recombination and provision of species-specific genomic annotations. Through community-driven efforts, we expanded the number of species in the catalog more than threefold and broadened coverage across the tree of life. During the process of expanding the catalog, we have identified common sticking points and developed the best practices for setting up genome-scale simulations. We describe the input data required for generating a realistic simulation, suggest good practices for obtaining the relevant information from the literature, and discuss common pitfalls and major considerations. These improvements to stdpopsim aim to further promote the use of realistic whole-genome population genetic simulations, especially in non-model organisms, making them available, transparent, and accessible to everyone.

This article is devoted to one of M.P. Musorgsky’s earliest romances, “Where Art Thou, Little Star?” which is the first number in his song collection The Years of Youth. The author of the article clarifies the circumstances under which the song was composed and reveals the circle of people connected with the dedicatee, the singer and writer I.L. Grünberg (Laskos). The article discusses author’s versions of the music, including the original manuscript stored at the Bibliothèque nationale de France (Paris). The detailed textual-critical and literary-historical commentaries enacted in the Academic Edition of M.P. Mussorgsky’s Complete Works, the work on which is performed at the State Institute for Art Studies, demonstrate the principles of commenting on the composer’s chamber vocal legacy.

Background: Inflammatory bowel disease (IBD) prevalence in Eastern Europe is increasing. The 30-day readmission rate is a crucial quality metric in healthcare, reflecting the effectiveness of initial treatment and the continuity of care post-discharge; however, such parameters are rarely analyzed. The aim of this study was to explore the trends in 30-day readmissions among patients with inflammatory bowel disease in Latvia between 2014 and 2020. Methods: This is a retrospective trends study in IBD—ulcerative colitis and Crohn’s disease (UC and CD)—patients in Latvia between 2014 and 2020, involving all IBD patients identified in the National Health service database in the International Classification of Diseases-10 (ICD) classification (K50.X and K51.X) and having at least one prescription for IBD diagnoses. We assessed all IBD-related hospitalizations (discharge ICD codes K50X and K51X), as well as hospitalizations potentially related to IBD comorbidities. We analyzed hospitalization trends and obtained the 30 day all-cause readmission rate, disease specific readmission rate and readmission proportion for specific calendar years. Trends in readmissions and the mean length of stay (LOS) for CD and UC were calculated. Results: Despite a decrease in admission rates observed in 2020, the total number of readmissions for CD and UC has increased. Female patients prevailed through the study period and were significantly older than male patients in both the CD and UC groups, p < 0.05. We noted that there was no trend for 30 day all-cause readmission rate for CD (p > 0.05); however, there was a statistically significant trend for 30 day all-cause readmission for UC patients (p-trend = 0.018) in the period from 2014 to 2019. There was a statistically significant trend for CD-specific readmission rate (p < 0.05); however, no statistically significant trend was observed for UC-specific readmission (p > 0.05). An exploratory analysis did not reveal any statistically significant differences between treated and not-treated IBD patients (p > 0.05). The increasing trend is statistically significant over the period 2014–2018 (p < 0.05); however, the trend interrupts in 2020, which can be associated with the COVID-19 global pandemic and the related changes in admission flows where the gastroenterology capacity was reallocated to accommodate increasing numbers of COVID-19 patients. More studies are needed to evaluate the long-term impact of COVID-19 pandemic and 30-day readmissions. No significant dynamics were observed in the mean total hospitalization costs over the 2014–2020 period.

Abstract Rodent betaherpesviruses vary considerably in genomic content, and these variations can result in a distinct pathogenicity. Therefore, the identification of unknown betaherpesviruses in house mice (Mus musculus), the most important rodent host species in basic research, is of importance. During a search for novel herpesviruses in house mice using herpesvirus consensus PCR and attempts to isolate viruses in tissue culture, we identified a previously unknown betaherpesvirus. The primary PCR search in mouse organs revealed the presence of known strains of murine cytomegalovirus (Murid herpesvirus 1) and of Mus musculus rhadinovirus 1 only. However, the novel virus was detected after incubation of organ pieces in fibroblast tissue culture and subsequent PCR analysis of the supernatants. Long-distance PCR amplification including the DNA polymerase and glycoprotein B genes revealed a 3.4 kb sequence that was similar to sequences of rodent cytomegaloviruses. Pairwise sequence comparisons and phylogenetic analyses showed that this newly identified murine virus is most similar to the English isolate of rat cytomegalovirus, thereby raising the possibility that two distinct CMV lineages have evolved in both Mus musculus and Rattus norvegicus.

This study examined the effectiveness of coating demineralized bone matrix (DBM) with amorphous calcium phosphate (DBM + CaP), as well as a composite of DBM, calcium phosphate, and serum albumin (DBM + CaP + BSA). The intact structure of DBM promotes the transformation of amorphous calcium phosphate (CaP) into dicalcium phosphate dihydrate (DCPD) with a characteristic plate shape and particle size of 5–35 µm. The inclusion of BSA in the coating resulted in a better and more uniform distribution of CaP on the surface of DBM trabeculae. MG63 cells showed that both the obtained forms of CaP and its complex with BSA did not exhibit cytotoxicity up to a concentration of 10 mg/mL in vitro. Ectopic (subcutaneous) implantation in rats revealed pronounced biocompatibility, as well as strong osteoconductive, osteoinductive, and osteogenic effects for both DBM + CaP and DBM + CaP + BSA, but more pronounced effects for DBM + CaP + BSA. In addition, for the DBM + CaP + BSA samples, there was a pronounced full physiological intrafibrillar biomineralization and proangiogenic effect with the formation of bone-morrow-like niches, accompanied by pronounced processes of intramedullary hematopoiesis, indicating a powerful osteogenic effect of this composite.

Creating bioactive materials for bone tissue regeneration and augmentation remains a pertinent challenge. One of the most promising and rapidly advancing approaches involves the use of low-temperature ceramics that closely mimic the natural composition of the extracellular matrix of native bone tissue, such as Hydroxyapatite (HAp) and its phase precursors (Dicalcium Phosphate Dihydrate—DCPD, Octacalcium Phosphate—OCP, etc.). However, despite significant scientific interest, the current knowledge and understanding remain limited regarding the impact of these ceramics not only on reparative histogenesis processes but also on the immunostimulation and initiation of local aseptic inflammation leading to material rejection. Using the stable cell models of monocyte-like (THP-1ATRA) and macrophage-like (THP-1PMA) cells under the conditions of LPS-induced model inflammation in vitro, the influence of DCPD, OCP, and HAp on cell viability, ROS and intracellular NO production, phagocytosis, and the secretion of pro-inflammatory cytokines was assessed. The results demonstrate that all investigated ceramic particles exhibit biological activity toward human macrophage and monocyte cells in vitro, potentially providing conditions necessary for bone tissue restoration/regeneration in the peri-implant environment in vivo. Among the studied ceramics, DCPD appears to be the most preferable for implantation in patients with latent inflammation or unpredictable immune status, as this ceramic had the most favorable overall impact on the investigated cellular models.

The article is devoted to the consideration of the actual problem of integration of transport system management tasks. The distribution of tasks on three levels of management – strategic, tactical and operational is considered. The purpose of the study is to present the results of structural modeling of transport system management tasks at different levels of management and to identify integrating elements. Structural modeling is carried out and five diagrams are presented, including two contextual ones. The schedule of regular passenger transport has been identified as an integrating element of the tactical level of transport system management. The developed structural diagrams show the feedback between the tactical and operational levels of transport system management. The conclusions and discussion of the results of the study are presented.

Background: Inflammatory bowel disease (IBD) prevalence in Eastern Europe is increasing. The 30-day readmission rate is a crucial quality metric in healthcare, reflecting the effectiveness of initial treatment and the continuity of care post-discharge; however, such parameters are rarely analyzed. The aim of this study was to explore the trends in 30-day readmissions among patients with inflammatory bowel disease in Latvia between 2014 and 2020. Methods: This is a retrospective trends study in IBD—ulcerative colitis and Crohn's disease (UC and CD)—patients in Latvia between 2014 and 2020, involving all IBD patients identified in the National Health service database in the International Classification of Diseases-10 (ICD) classification (K50.X and K51.X) and having at least one prescription for IBD diagnoses. We assessed all IBD-related hospitalizations (discharge ICD codes K50X and K51X), as well as hospitalizations potentially related to IBD comorbidities. We analyzed hospitalization trends and obtained the 30 day all-cause readmission rate, disease specific readmission rate and readmission proportion for specific calendar years. Trends in readmissions and the mean length of stay (LOS) for CD and UC were calculated. Results: Despite a decrease in admission rates observed in 2020, the total number of readmissions for CD and UC has increased. Female patients prevailed through the study period and were significantly older than male patients in both the CD and UC groups, p < 0.05. We noted that there was no trend for 30 day all-cause readmission rate for CD (p > 0.05); however, there was a statistically significant trend for 30 day all-cause readmission for UC patients (p-trend = 0.018) in the period from 2014 to 2019. There was a statistically significant trend for CD-specific readmission rate (p < 0.05); however, no statistically significant trend was observed for UC-specific readmission (p > 0.05). An exploratory analysis did not reveal any statistically significant differences between treated and not-treated IBD patients (p > 0.05). The increasing trend is statistically significant over the period 2014–2018 (p < 0.05); however, the trend interrupts in 2020, which can be associated with the COVID-19 global pandemic and the related changes in admission flows where the gastroenterology capacity was reallocated to accommodate increasing numbers of COVID-19 patients. More studies are needed to evaluate the long-term impact of COVID-19 pandemic and 30-day readmissions. No significant dynamics were observed in the mean total hospitalization costs over the 2014–2020 period. [ABSTRACT FROM AUTHOR]

Intestinal ultrasound is a new non-invasive imaging method that can be used for diagnostics of inflammatory bowel disease, to evaluate the response to therapy, and monitor serious complications of the disease in time. A prospective study was performed in Pauls Stradiņš Clinical University Hospital. Thirty patients were enrolled in the study: 21 patients with ulcerative colitis and 9 patients with Crohn's disease. Intestinal ultrasound was performed using Diagnostic Ultra-sound System Arietta S70 (Hitachi, Japan). Intestinal wall structure (thickness), blood flow (Limberg score), intraluminal content, mesenteric fat hypertrophy and lymph nodes were evaluated, and laboratory markers of inflammation and clinical activity indices were analysed. Increased bowel wall thickness (BWT) (≥ 3 mm) was detected in 22 patients (73.3%), and wall stratification in 17 patients (56.7%). Using statistical analysis, it was concluded that there was a positive and statistically significant correlation between bowel wall thickness and ferritin (r = 0.60; p < 0.001), CRP (r = 0.49, p = 0.006), and faecal calprotectin (r = 0.84, p < 0.001). Intestinal ultra-sound is a promising real time monitoring method for both Crohn's disease and ulcerative colitis, which showed statistically significant correlations between bowel wall thickness, bowel wall stratification, blood flow, laboratory markers of inflammation and clinical activity indices. [ABSTRACT FROM AUTHOR]