STUDY OF THE INFLUENCE OF CALCIUM OXIDES IN LIGHT-FUSION RAW MATERIALS ON THE PROPERTIES OF A CERAMIC PRODUCT

One of the main problems of modern building ceramics based on low-melting raw materials is the increased CaO content in the charge. This deviation from the normative values of the technological parameters of production leads to defects - underburning / overburning, quirks, looseness, low strength. Firing mode, molding parameters, addition of additives, preparation of raw materials are the factors for solving this problem. The Alekseevsk low-melting clay and the Yarmysh (Uzbekistan) loess-like loam were investigated, the destruction of the sample structure upon absorption of moisture from the CaO air was graphically modeled, the diagrams of the dependence of the fi ring temperature on the compressive strength were plott ed, the infl uence of molding and the fi neness of grinding of raw materials on the compressive strength and the nature of the formation of ceramic defects was derived.

Super-resolved 3D mapping of molecular orientation with vibrational techniques

When a sample has an anisotropic structure, it is possible to obtain different information, when changing polarization of incident light. Using polarized light of a single vibrational band to determine the in-plane orientation and internal ordering of a sample is a typical practice in materials science. Acquiring mapping data at four different polarizations with a stationary sample than just at two polarizations offers much more insight into the sample structure with proper mathematical treatment. A concurrent analysis of two vibrational bands with perpendicular transition moment orientations allows the understanding of the orientational ordering in three dimensions. We show here, to the best of our knowledge, the first application of concurrent analysis to IR spectromicroscopy data and obtain orientation angles of a model spherulite polycaprolactone sample. Moreover, we show that this method can be easily applied to high resolution, diffraction limited FT-IR and Raman imaging and even to sub-diffraction limit O-PTIR imaging. Due to the non-tomographic experimental approach, no image distortion is visible and nanometer scale orientation domains can be observed. 3D bond orientation maps will enable in-depth characterization of sample structure in a quantitative manner enabling more precise control of their physicochemical properties and function.

Super-resolved 3D mapping of molecular orientation with vibrational techniques

When a sample has an anisotropic structure, it is possible to obtain different information, when changing polarization of incident light. Using polarized light of a single vibrational band to determine the in-plane orientation and internal ordering of a sample is a typical practice in materials science. Acquiring mapping data at four different polarizations with a stationary sample than just at two polarizations offers much more insight into the sample structure with proper mathematical treatment. A concurrent analysis of two vibrational bands with perpendicular transition moment orientations allows the understanding of the orientational ordering in three dimensions. We show here, to the best of our knowledge, the first application of concurrent analysis to IR spectromicroscopy data and obtain orientation angles of a model spherulite polycaprolactone sample. Moreover, we show that this method can be easily applied to high resolution, diffraction limited FT-IR and Raman imaging and even to sub-diffraction limit O-PTIR imaging. Due to the non-tomographic experimental approach, no image distortion is visible and nanometer scale orientation domains can be observed. 3D bond orientation maps will enable in-depth characterization of sample structure in a quantitative manner enabling more precise control of their physicochemical properties and function.

Estimates of Prevalence Rates of Cancer Patients With Children and Well-Being in Affected Children: A Systematic Review on Population-Based Findings

This review assessed population-based estimate rates of cancer patients with minor and young adult children (≤ 25 years), children and young adults having a parent with cancer as well as the psychosocial situation and well-being of children and young adults affected by parental cancer. Eighteen publications on population-based studies were included. Studies varied in the age ranges of both cancer patients and children. The prevalence rates of cancer patients having children ranged from 14 to 24.7% depending on the sample structure (e.g., age, gender). Studies reported that between 1.6 and 8.4% of children resp. young adult children have a parent with a history of cancer. Seven publications reported on the psychosocial situation or well-being in children and young adults affected by parental cancer. Estimate rates of psychosocial problems, psychiatric diagnoses or distress ranged between 2.5 and 34% of children depending on the method of measurement and outcome. The differences in the sample structure between the studies impeded the comparison of prevalence rates. However, the findings help to determine the need for specific support services and health care planning. The results emphazise the importance to routinely include issues on the parental role of patients and questions on the well-being and coping of children into psychooncological care. If necessary, support should be provided to families living with a cancer diagnosis.

Influence of Sulphate Attack on Properties of Modified Cement Composites

Monitoring the condition of building structures based on composite materials in aggressive environments shows that the deterioration of basic properties occurs under the influence of various factors such as temperature and humidity changes,in addition to changes in the chemical composition of air environment. In addition, the composite materials during the operation must retain not only the mechanical properties laid down at the design stage, but also the electro-physical characteristics, regardless of the type of destructive effects. In the current study, the quantitative assessment of the result of the interaction of an aggressive sulphate-containing medium with composites modified with conductive and dielectric additives was carried out. The effect of sulphateattack on the specific electrical conductivity of cement composites was studied. The nature of the interaction was evaluated by changing the properties of the samples of the developed compositions under the influence of a single-normal solution of sodium sulphate. The analysis was carried out by means of potentiometric titration using the exchange interaction method by fixing the degree of absorption of sulphate ions and determining the concentration of calcium ions in the solution. The measurement of the solution potential allowed determination of the quantitative indicators of the rate of calcium hydroxide leaching from the sample structure,which is necessary to assess the intensity of the destruction process and determine the nature of the change in strength properties.Measurements of the electrical resistivity of samples under the constant influence of sulphate aggression were taken during 28 days of observation. A method for quantifying the effect of a sulphate medium on a cement matrix was proposed that enables the material durability to be predicted. The features of changes in the morphology of structural components after exposure to aggressive solution were determined by physical and chemical methods.

Quantitative analysis of speckle-based X-ray dark-field imaging using numerical wave-optics simulations

The dark-field signal measures the small-angle scattering strength and provides complementary diagnostic information. This is of particular interest for lung imaging due to the pronounced small-angle scatter from the alveolar microstructure. However, most dark-field imaging techniques are relatively complex, dose-inefficient, and require sophisticated optics and highly coherent X-ray sources. Speckle-based imaging promises to overcome these limitations due to its simple and versatile setup, only requiring the addition of a random phase modulator to conventional X-ray equipment. We investigated quantitatively the influence of sample structure, setup geometry, and source energy on the dark-field signal in speckle-based X-ray imaging with wave-optics simulations for ensembles of micro-spheres. We show that the dark-field signal is accurately predicted via a model originally derived for grating interferometry when using the mean frequency of the speckle pattern power spectral density as the characteristic speckle size. The size directly reflects the correlation length of the diffuser surface and did not change with energy or propagation distance within the near-field. The dark-field signal had a distinct dependence on sample structure and setup geometry but was also affected by beam hardening-induced modifications of the visibility spectrum. This study quantitatively demonstrates the behavior of the dark-field signal in speckle-based X-ray imaging.

THE HEALTH EFFECTS OF WORKING ON THE COMPUTER: WARNING SIGNS

Computerisation and digitisation are an engine of social and economic change. Implementation and coordination of both work and leisure activities are already unthinkable without computers and smart devices. The benefits of computerisation are available immediately in the forms of faster problem solving, cost-saving, or the environmental impacts of using less paper in administration. However, the fact that we spend more and more time in front of computers also raises health issues. Harmful effects of bad sitting posture, short lightning or other factors conveniently fade into the background. An important reason for this is that their representation differs in time. The human body can adapt flexibly to various external factors; the formation of irreversible changes requires a relatively long time, which gradually evolves. Because of this asymmetry, a notice of preliminary signals and a preventive approach is highly advised. This paper contributes to the ergonomic knowledge base by exploring the opinions about the early warning signs of the problems among higher education students. The analysis is based on the responses of 591 students to a voluntary online survey. The sample structure by age and job experience points to the increase of problems, drawing attention to necessary development actions.

Impact of the Co Doping on the Structure, Magnetic Properties, and Phase Transition in Ni50-xCoxMn38Sn12 Ribbons

Three Heusler alloys, Ni50-xCoxMn38Sn12 (x = 1, 2, and 3), were elaborated by rapid solidification. The impact of the Co doping on the structure, magnetic properties, and phase transition in these alloys was studied. The structure of the Ni49Co1Mn38Sn12 and Ni48Co2Mn38Sn12 ribbons was martensite 14M monoclinic structure, while the Ni47Co3Mn38Sn12 sample structure was austenite cubic L21. The thermal analysis showed the impact of the substitution Ni by Co. It was noted that the temperatures of martensitic transition moved lower, and a decreases progressively of enthalpy and entropy changed. Likewise, an obvious increase in the temperature of Curie transition for austenite phase (TAC) was observed and a jump of magnetization change (ΔM) was detected, with increasing Cobalt content.

Ultraviolet Luminescence of ZnO Whiskers, Nanowalls, Multipods, and Ceramics as Potential Materials for Fast Scintillators

The presented work is dedicated to the study and comparison of scintillating properties of zinc oxide samples prepared in different morphologies: whiskers, nanowalls, multipods, and ceramics. It was shown that total transmittance, photo- and radioluminescence spectra, and radioluminescence kinetics can vary significantly depending on sample structure and preparation conditions. The highest total transmittance was registered for ZnO ceramics (>50% at 0.5 mm thickness). Differences in the transmittance of whiskers, nanowalls, and multipods can be attributed to their shape and thickness which affects the amount of light refraction and scattering. The study of radioluminescence demonstrated that all samples, except undoped ceramics and air annealed whiskers, have predominantly fast luminescence with a decay time <1 ns. High transmittance of ceramics opens the way for their use in the registration of high energy X-ray and gamma radiation, where a large volume of scintillators is required. In cases, where large scintillator thickness is not a necessity, one may prefer to use other ZnO structures, such as ensembles of whiskers and nanowalls. Studies of near-band-edge luminescence components at low temperatures showed that the structure is quite similar in all samples except Ga doped ceramics.

MR-APSS: a unified approach to Mendelian Randomization accounting for pleiotropy and sample structure using genome-wide summary statistics

Mendelian Randomization (MR) has proved to be a powerful tool for inferring causal relationships among a wide range of traits using GWAS summary statistics. Great efforts have been made to relax MR assumptions to account for confounding due to pleiotropy. Here we show that sample structure is another major confounding factor, including population stratification, cryptic relatedness, and sample overlap. We propose a unified MR approach, MR-APSS, to account for pleiotropy and sample structure simultaneously by leveraging genome-wide information. By further correcting bias in selecting genetic instruments, MR-APSS allows to include more genetic instruments with moderate effects to improve statistical power without inflating type I errors. We first evaluated MR-APSS using comprehensive simulations and negative controls, and then applied MR-APSS to study the causal relationships among a collection of diverse complex traits. The results suggest that MR-APSS can better identify plausible causal relationships with high reliability, in particular for highly polygenic traits.