Transfer efficiency of an enveloped virus, human coronavirus 229E, from various hard surface fomites to finger pads of the hands

Respiratory viruses can be transmitted by fomite contact, but no data currently exist on the transfer of enveloped viruses. The transfer efficiency of human coronavirus from various hard surfaces ranged from 0.46% to 49.0%. This information can be used to model the fomite transmission of enveloped viruses.

Improving the mathematical stability in the numerical simulation of the vehicle movement with an electronic movement control system

The aim of the study is to determine the influence of the calculated radius type on the calculated parameters of the vehicle movement, equipped with an electronic movement control system. A numerical simulation of the vehicle movement equipped with an electronic movement control system was carried out. Under calculated conditions, there are forces that disrupt the stable and controlled vehicle movement. The studies carried out have shown that in the numerical simulation of the parameters of the vehicle movement, the use of a dynamic radius instead of a rolling radius never affects the calculated values of the vehicle’s longitudinal shifts. In this case, the values of the lateral shifts and the turning angle of the vehicle on a dry hard surface change insignificantly, but there is a significant mathematical instability of the solution. On a wet hard surface, the influence of the calculated radii types on the characteristics of the simulated vehicle movement is preserved, but this influence is less pronounced.

Identification of enamel knot gene signature within the developing mouse molar

In most mammals, the primary teeth develop in utero and the cells capable of contributing to hard surface regeneration are lost before tooth eruption. These cells differentiate through a series of reciprocal induction steps between the epithelium and mesenchyme, initially orchestrated by an epithelial signaling center called the enamel knot. While the factors secreted by this structure are of interest to the dental regeneration and development communities, its small size makes it difficult to isolate for analysis. Here we describe our work to identify the enamel knot from whole E14 molars using publicly available scRNA-seq data. We identified 335 genes differentially expressed in the enamel knot compared to the surrounding tissues, including known enamel knot marker genes. We validated expression of the most highly enriched enamel knot marker genes and identified 42 novel marker genes of the enamel knot which provide excellent targets for future dental regeneration investigations.

Production of gradient ultrafine-grained hard alloys from powders obtained from scrap VK15 alloy dispersed in water and scrap VK8 alloy dispersed in oil

An experiment has been carried out aimed at producing a low-cost tool material which would have an extra hard surface and a crack resistant base phase. A double-layer gradient alloy was produced out of powders with excessive and insufficient carbon obtained from alloys VK8 and VK15 by electrospark dispersion. To obtain the initial powder, plates of the VK8 alloy scrap material initially containing 5.6% of carbon were dispersed in oil. This caused excessive carbon (3.1%), which was then partially reduced to 0.6% by CO2 heat treatment. The VK15 alloy with 5.3% of initial carbon was dispersed in water to achieve an insufficient carbon concentration (2.8 %) in it. It was then heat treated in the CO atmosphere to partially lower the carbon concentration to 0.7%. The dispersed powder was found to consist of spherical microparticles, as well as agglomerated nanoparticles obtained through crystallization of liquid and vapour phases. Mixing of tungsten and cobalt phases resulted in much smaller diameters of WC grains in the newly sintered alloy. This combination of deviations in the carbon concentration between the layers helped maintain the unequal concentration of cobalt (8 and 15%) and thus ensure an extra hard surface (1820HV) and a crack resistant base (14.2 MPa√m). Analysis was carried out to estimate the power costs, as well as the performance of the laboratory unit used for electrospark dispersion of hard alloys.

Influence of anti-ice chemicals on reduction of strength properties of cement concrete

In this article were analyzed the problems of liquidation winter slipperiness on the roads with hard surface using chemical reagents. The article analyzes the results of tests using traditional (chloride) and non-traditional chemical reagents and their influence on the strength properties of cement concrete.

Level of Vocabulary Development and Selected Elements Regarding Sensory Integration and Balance in 5-Year-Old Girls and Boys

The aim of this research was to assess relationships between the level of vocabulary and selected elements of sensory integration and balance in 5-year-old girls and boys, showing the differences between them. The study group consisted of 290 5-year-old children (172 boys and 118 girls) with different levels of vocabulary development and selected disturbances in sensory integration and balance processes. To evaluate the developmental deficits of speech with regard to vocabulary, the Children’s Dictionary Test was used. The Clinical Test of Sensory Integration and Balance was also employed. In our research’s overall assessment, 118 children, i.e., 41%, had a low level of vocabulary, while 108 (37%) had an average level and 64 (22%) had a high level. However, the average score of all examined children (3.71 stens) indicates a low level of vocabulary development. Less developed vocabulary skills included the ability to create subordinate words and define concepts. There were no significant differences in the level of vocabulary between girls and boys. We observed disorders concerning selected elements of sensory integration and balance in most of the children, and more often in boys. There were statistically significant relationships between the level of vocabulary and selected disorders of sensory integration and balance; however, they were not unambiguous. Children with the lowest level of vocabulary in overall assessment obtained significantly the worst results in the Clinical Test of Sensory Integration and Balance (CTSIB) open eyes, hard surface test. However, in the closed eyes, hard surface test, the lowest score was obtained by children with a high overall assessment. In turn, in the open eyes, soft surface test, the lowest score was noted for children with average overall assessment. In the complex CTSIB test, the lowest score was achieved by children with low ability to define concepts. The problem of the relationship between vocabulary level of and sensory integration as well as balance requires further research. The demonstrated significant relationships between some aspects of vocabulary level and selected elements of sensory integration as well as balance confirm the need to care for the overall psychomotor sphere of a child.