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Purpose: Molecular oxygen, besides a photosensitizer and light of appropriate wavelength, is one of the three factors necessary for photodynamic therapy (PDT). In tumor tissue, PDT leads to the killing of tumor cells, destruction of endothelial cells and vasculature collapse, and the induction of strong immune responses. All these effects may influence the oxygenation levels, but it is the vasculature changes that have the main impact on pO2. The purpose of our study was to monitor changes in tumor oxygenation after PDT and explore its significance for predicting long-term treatment response. Procedures: Electron paramagnetic resonance (EPR) spectroscopy enables direct, quantitative, and sequential measurements of partial pressure of oxygen (pO2) in the same animal. The levels of chlorophyll derived photosensitizers in tumor tissue were determined by transdermal emission measurements. Results: The noninvasive monitoring of pO2 in the tumor tissue after PDT showed that the higher ΔpO2 (pO2 after PDT minus pO2 before PDT), the greater the inhibition of tumor growth. ΔpO2 also correlated with higher levels of the photosensitizers in the tumor and with the occurrence of a severe edema/erythema after PDT. Conclusion: Monitoring of PDT-induced changes in tumor oxygenation is a valuable prognostic factor and could be also used to identify potentially resistant tumors, which is important in predicting long-term treatment response. [ABSTRACT FROM AUTHOR]

According to the hypothesis of Maloney et al. (Cognition 114(2):293–297, 2010. https://doi.org/10.1016/j.cognition.2009.09.013), math anxiety is related to deficits in numerical magnitude processing, which in turn compromises the development of advanced math skills. Because previous studies on this topic are contradictory, which may be due to methodological differences in the measurement of numerical magnitude processing, we tested Maloney et al.'s hypothesis using different tasks and their indicators: numerical magnitude processing (symbolic and non-symbolic comparison tasks: accuracy, reaction time, numerical ratio, distance and size effects, and Weber fraction; number line estimation task: estimation error), math anxiety (combined scores of learning, testing, math problem solving, and general math anxiety), and math performance. The results of our study conducted on 119 young adults mostly support the hypothesis proposed by Maloney et al. that deficiency in symbolic magnitude processing is related to math anxiety, but the relationship between non-symbolic processes and math anxiety was opposite to the assumptions. Moreover, the results indicate that estimation processes (but not comparison processes) and math anxiety are related to math performance in adults. Finally, high math anxiety moderated the relationship between reaction time in the symbolic comparison task, reaction time in the non-symbolic comparison task, numerical ratio effect in the symbolic comparison task, and math performance. Because the results of the joint effect of numerical magnitude processing and math anxiety on math performance were inconsistent, this part of the hypothesis is called into question. [ABSTRACT FROM AUTHOR]

Although risk is often considered in the context of maladaptive behaviors, risks can also be positive, allowing individuals to pursue meaningful goals in a socially accepted way. In this study, we were interested in examining psychological profiles associated with positive and negative risk-taking in adults (N = 275, ages 19–71 years, M = 39.25; SD = 13.73) using latent profile analysis. Specifically, we examined whether distinct profiles of psychological characteristics such as future time perspective, tolerance to ambiguity, and sensitivity to reward and punishment are differentially associated with positive and negative risk-taking. We used the Future Time Perspective Scale (FTPS), the Multiple Stimulus Types Ambiguity Tolerance Scale (MSTAT-II), the Short Version of the Sensitivity to Punishment and Sensitivity to Reward Scale (SPSRQ-SF), the Positive Risk-Taking Scale (PRTS), and the Negative Risk-Taking Scale (NRTS). Findings yielded two profiles: individuals in the first profile, characterized by lower sensitivity to punishment and higher tolerance to ambiguity, future time perspective, and sensitivity to reward, endorsed greater positive and negative risk-taking. Conversely, individuals in the second profile, characterized by heightened sensitivity to punishment and lower tolerance to ambiguity, future time perspective, and sensitivity to reward, endorsed lower positive and negative risk-taking. The study contributes to previous findings by identifying additional psychological characteristics that may be associated with both positive and negative risk-taking in adults. [ABSTRACT FROM AUTHOR]

Purpose: The paper presents the design and model of energy harvester prototype consisting of vibration generator and magnetic spring. The developed magnetic spring prototype, which is integrated in the vibration generator, detects several resonance frequencies significant for energy harvester optimization and ensures more applications in engineering technology. Methods: The magnetic spring with two identical fixed magnets and the movable permanent magnet that levitates between the two fixed magnets in a vertical direction and moves linearly, can harvest multi-directional environment vibration resembled by vibration generator. The magnetic spring acts as the clamping system for the levitated magnet. Mechanical energy gained through vibrations resembled by vibration generator is converted by the magnetic spring into electrical energy. Results: Numerical calculations and experimental tests including measurements of I–V, total harmonic distortion (THD) of displacements and magnetic induction conducted in Laboratory have been useful to determine the characteristics and performance of the magnetic spring integrated in electromagnetic vibration generator. Conclusion: The I–V impedance measurements have exhibited a significantly stronger dependence on frequencies resonances and the measurements of magnetic induction intensity show the demagnetization and magnetization processes of the levitated permanent magnets. [ABSTRACT FROM AUTHOR]

The aim of the article is to present the Mathematics Attitude Scale for Adults (MASA) – a new, three-dimensional questionnaire of attitude towards mathematics for adults which contains cognitive, affective, and behavioral components. The exploratory and confirmatory factor analyses established a three-factor structure of the MASA and measurement invariance across gender and groups of students and non-students. The convergent and divergent validity was confirmed, which shows that women have a more positive math attitude than men, and that STEM students have a more positive attitude than humanistic/social science students and non-students. The results also showed that a more positive math attitude is related to lower math anxiety and higher math self-concept, math self-efficacy, math grades, and math state final exam. Moreover, a higher MASA score is related to lower results in Polish language self-concept, Polish language self-efficacy, Polish language grades, and Polish language state final exam. Satisfactory internal consistency and test-retest reliability was also demonstrated. The MASA has very good psychometric properties. Therefore, it can be recommended to investigate math attitude in various groups of adults. [ABSTRACT FROM AUTHOR]

Adolescents are expected to take more risks than adults. The presented study was designed to determine whether adolescent risk-taking results from high reward sensitivity and poor cognitive control. In particular, we aimed to examine whether the impact of these variables is more visible in rewarding than non-rewarding conditions. Ninety adolescents (aged 13–16) and 95 young adults (aged 20–28) took part in the study. We used a driving task in rewarded and non-rewarded conditions to measure risk-taking. We also used tasks measuring reward sensitivity, cognitive control and impulsivity. Additionally we used self-report measures of reward sensitivity, self-control and everyday risk-taking to see whether the effects observed for self-reports mimic the effects observed for behavioral tasks. We found that the higher the reward sensitivity, the more adolescents (but not adults) risk in the rewarded condition of a driving task. We found no impact of cognitive control or impulsivity on risk-taking, regardless of age and condition. At the self-report level, we found that the higher the reward sensitivity and the poorer the self-control, the more both adolescents and adults displayed everyday risk-taking behavior. [ABSTRACT FROM AUTHOR]

Parenting perfectionism, especially the dimension of perfectionistic concerns—preoccupation with self-criticism including concern over mistakes and doubts about own behaviors—, has been shown to be a weighty factor for parental burnout. Drawing on the Balance between Risks and Resources (BR2) theory of parental burnout, this paper examines whether emotional competence could moderate/buffer the effect of parenting perfectionism on parental burnout. We investigated this question in two independent samples of parents collected in Belgium (N = 347) and Poland (N = 377). The results of both studies show that emotional competence cancels out the detrimental effect of perfectionistic concerns on parental burnout. Beyond its contribution to parenting perfectionism and emotional competence literatures, the present article also provides further evidence of the potential of the BR2 theory of parental burnout. [ABSTRACT FROM AUTHOR]

The Late Cretaceous orogeny followed by the Eocene collision of the Adriatic with the European plate dissected the Northern Calcareous Alps (NCA) by a number of well-studied strike-slip fault systems accommodating N-S shortening and E-W stretching. However, the post-Miocene fault activity is poorly constrained due to lack of Neogene faulted sediments, and glacial erosion of geomorphic indicators. Using the protected environment of caves, we fill the knowledge gap in the post-Miocene evolution of the NCA by paleostress analysis of 172 reactivated faults that offset passages in 28 caves near major faults. Constrained maximum age of caves, our results indicate that the NCA have been subjected to N to NE trending compression since Pliocene. Faulted speleothems dated with 230Th/U method, indicate that the recorded present-day stress state did not significantly change during the last 0.5 Ma. In contrast to the previously proposed post-Miocene N-S extension of NCA, but in agreement with what was observed in Vienna and Pannonian basins, we conclude that the eastward extrusion resulting from N-S convergence has continued despite a distinct slowdown of plate tectonic velocities in the late Miocene. The N-S extension affected only the Alpine front during Pliocene Molasse basin inversion, while at the scale of the Alpine orogen the NCA underwent successive N-S shortening and E-W stretching. [ABSTRACT FROM AUTHOR]

The Na3RE(PO4)2 phosphates (where RE: La, Ce, Nd, Gd or Er) were obtained by precipitation from sols under mild hydrothermal conditions. Characterization of the powders was carried out by XRD, SEM, ICP/OES and DSC/TG methods. The resulted molar ratio of Na:RE:P in the precipitates was equal 3:1:2 and proved the successful synthesis of Na3RE(PO4)2 compounds. The powders consisted of non-agglomerated spindle or flower-like shaped grains with the size up to 5 microns. The most of the obtained powders have a trigonal structure, which is a characteristic feature of high-temperature polymorphs of Na3RE(PO4)2. An exception is the Na3La(PO4)2 compound, which crystallized in an unidentified type of structure. Under heating, the Na3RE(PO4)2 phosphates change their structure. Their polymorphic transformation path, i.e. temperatures of transitions and their structural changes, is dependent on RE3+ radius size. For La, Ce and Nd compounds heated at high temperatures, only orthorhombic polymorphs have been observed, whereas monoclinic or orthorhombic polymorphs of Na3Er(PO4)2 and Na3Gd(PO4)2 phosphates can form in the course of sintering. [ABSTRACT FROM AUTHOR]

The article demonstrates if automatic optimization can be better than manual adjustment. The subject of optimization was the temperature-phased anaerobic digestion (TPAD) model. A selection of 3 parameters per each reactor in the process chain was appointed—reaction rate for propionate conversion, acetate conversion, and hydrolysis. Overall, both methods provided very convergent results. However, the total summary error (TSE) for the automatic algorithm was always moderately lower than for manual—the difference varied between 16.16 and 57.05 percentage points. Although the manual method has significant advantages—adjustment was more homogenous and gave more uniform fitting. Finally, cross-validation was performed to unify the values between the experimental series. The result was a total number of 4 values for each optimized constant—for two temperature points in each of two methods. Due to inconclusive information about the accuracy, averaged values were calculated to use in further researches. The recommendation from this article is to connect the best aspect of both methods to achieve the most accurate results. [ABSTRACT FROM AUTHOR]

Phase equilibria in the ErPO4–KPO3–Er(PO3)3 partial system were established, and the primary crystallization fields of the phosphates occurring in the composition range of ErPO4, KErP2O7, KPO3, Er(PO3)3, KEr(PO3)4 were defined. Two polythermal binary cross-sections, KErP2O7–Er(PO3)3 and KErP2O7–KEr(PO3)4, which are quasi-binary only in the subsolidus region (i.e. below 855 °C and 640 °C, respectively), were determined, and their phase diagrams were elaborated. Three invariant points, two ternary peritectics P1 (855 °C) and P2 (640 °C) as well as one ternary eutectic E (530 °C) were found in the ErPO4–KPO3–Er(PO3)3 system. Alloy crystallization ends with the solidification of the ternary eutectic (KErP2O7 + KEr(PO3)4 + KPO3). The studies were carried out by thermoanalytical methods (DSC/TG) and powder X-ray diffraction analysis (PXRD). [ABSTRACT FROM AUTHOR]

Brittle structures identified within the largest karstic cave of the Sudetes (the Niedźwiedzia Cave) were studied to reconstruct the paleostress driving post-Variscan tectonic activity in the NE Bohemian Massif. Individual fault population datasets, including local strike and dip of fault planes, striations, and Riedel shear, enabled us to discuss the orientation of the principal stresses tensor. The (meso) fault-slip data analysis performed both with Dihedra and an inverse method revealed two possible main opposing compressional regimes: (1) NE–SW compression with the formation of strike-slip (transpressional) faults and (2) WNW–ESE horizontal compression related to fault-block tectonics. The (older) NE-SW compression was most probably associated with the Late Cretaceous–Paleogene pan-regional basin inversion throughout Central Europe, as a reaction to ongoing African-Iberian-European convergence. Second WNW–ESE compression was active as of the Middle Miocene, at the latest, and might represent the Neogene–Quaternary tectonic regime of the NE Bohemian Massif. Exposed fault plane surfaces in a dissolution-collapse marble cave system provided insights into the Meso-Cenozoic tectonic history of the Earth's uppermost crust in Central Europe, and were also identified as important guiding structures controlling the origin of the Niedźwiedzia Cave and the evolution of subsequent karstic conduits during the Late Cenozoic. [ABSTRACT FROM AUTHOR]

The study investigated the relationship between math anxiety in parents and teachers and math anxiety and math achievement in first- to third-grade children. The results indicate that math anxiety in fathers (but not mothers and teachers) is associated with math anxiety in first-grade children and third-grade girls. Math anxiety in mothers and teachers (but not fathers) explains the level of math achievement in third-grade children. The research results indicate the importance of adults in shaping pupils' math anxiety and math achievement, but these relationships vary depending on gender and the grade year. The obtained outcomes generally suggest that adults' math anxiety is not a social source of children's math anxiety, but it can be considered a source of low math achievement among children in the final grade of early school education. [ABSTRACT FROM AUTHOR]

La1−xAgxFeO3 (x = 0.05–0.25) perovskites deposited on a honeycomb-shaped monolithic metallic support were used as catalysts for the total oxidation of hydrocarbons. Monolithic catalysts were prepared by washcoating honeycomb substrates with lanthanum-stabilized γ-Al2O3, on which La1−xAgxFeO3 was deposited. Catalysts with La1−xAgxFeO3 perovskites show higher activity for methane oxidation at x ≥ 0.05 and hexane oxidation at x ≥ 0.1 than LaFeO3 catalyst. The perovskite catalysts were characterized by XRD, XPS, SEM, TEM, TPR-H2, O2-TPD and BET specific surface area measurement. Ag forms solid solutions with the La1−xAgxFeO3 perovskite lattice for x = 0.05–0.1. In La1−xAgxFeO3 perovskites (x ≥ 0.1), Ag0 particles with average crystallite sizes from 31 to 41 nm were also identified. When Ag is introduced into the LaFeO3 perovskite, both the changes occurring after some Ag is incorporated into its structure and the presence of large crystallites of metallic silver contribute to the catalysts' activity increase. [ABSTRACT FROM AUTHOR]

Three-layer YO, CeO, SiO-AlO and SiO-AlO-YO-CeO coatings were deposited by sol-gel method on the FeCrAl alloy foil substrate. The protective properties of the coatings during high-temperature cyclic oxidation and the changes in the topography of the surface, the structure, and chemical composition of the FeCrAl alloy surface layer were examined. It has been shown that small additions of cerium and yttrium affect the morphology of the growing AlO scale. After 10 oxidation cycles in air ( T = 900 °C, t = 120 h, one cycle = 12 h), the smallest change in the mass of the samples was observed for YO and SiO-AlO-YO-CeO coatings with an appropriate yttrium and cerium content. The protection effectiveness of the coatings to that of uncoated substrate after 10 oxidation cycles ranges from 28 to 66 %. The oxidation scale thickness ( h) and the designated value of the parabolic rate constant ( k ) depended on the yttrium and cerium content in the coating. [ABSTRACT FROM AUTHOR]

Mn-Zn ferrite was prepared from the solution after acid leaching of spent batteries by co-precipitation method using ammonia oxalate, sodium carbonate and sodium hydroxide as precipitating agents. The co-precipitation process was performed at temperature of over 50 °C by continuous magnetic stirring. The precipitates were pre-sintered at 850 °C in air. Dilatometric study has revealed that lowest shrinkage (only 5.6%) showed a material obtained from an oxalate precipitant. After pressing and high-temperature sintering at 1325 °C, it showed both insufficient density and the presence of pores, which contribute to the deterioration in the magnetic properties of the ferrites: the low magnetic permeability value and high magnetic losses. Ferrite prepared from hydroxide and carbonate precipitant showed a much higher shrinkage, sintered density and much higher magnetic permeability compared with the ferrite prepared from oxalate precursor. [ABSTRACT FROM AUTHOR]

Studies on the separation of calcium and neodymium ions by using ethylenediaminetetraacetic acid (H4EDTA) as a complexing agent were performed. This research was undertaken due to the possibility of H4EDTA applying to isolate rare earth elements from the solution after acidic leaching of phosphogypsum, and because of the similarity of coordination properties of calcium and lanthanides ions. The experiment was carried out in model systems containing Ca2+ and Nd3+ ions in hydrochloric or sulphuric acid. The content of calcium and neodymium metals, phase composition and thermal behaviour of the obtained products were determined by ICP-OES, FTIR, XRD and TG/DTA techniques. During the separation process, the precipitates of a light pink colour were obtained. The obtained results show that the neodymium ethylenediaminetetraacetate has been successfully formed and that the isolation of neodymium ions was more efficient in chloride medium. The precipitate included 72.2 and 3.9% of the starting amount of neodymium and calcium used in the experiment, respectively. However, in sulphates medium, these amounts were equal to 73.8 and 53.5%, respectively. Moreover, the obtained powder was polluted with sulphates. The addition of the EDTA in an excess (15%) contributed only to an increase in calcium content in the complex. [ABSTRACT FROM AUTHOR]

Nonmetallic (based on polymers or oxides) and metallic protective coatings are used to protect metal products against the harmful action of the corrosion environment. In recent years, self-healing coatings have been the subject of increasing interest. The ability of such coatings to self-repair local damage caused by external factors is a major factor contributing to their attractiveness. Polymer layers, silica-organic layers, conversion layers, metallic layers and ceramic layers, to mention but a few, are used as self-healing coatings. This paper presents the main kinds of self-healing coatings and explains their self-healing mechanisms. [ABSTRACT FROM AUTHOR]

The characterization of three commercial powders of niobium(V) oxide received from two producers was made. The thermal behavior of NbO up to melting point and its microstructure were studied using X-ray powder diffraction, thermoanalytical methods (DSC/TG), infrared spectroscopy (IR) and scanning microscopy. Analysis of the obtained results revealed that the starting structure of niobium(V) oxide and its thermal behavior depend on the origin of niobia. Depending on the origin of the powder and of its thermal treatment, three polymorphs of NbO can be observed. Sintering of powders above 1200 °C results in the formation of single phase, H-NbO. [ABSTRACT FROM AUTHOR]

The study is focused on the CO decomposition on small (6-, 7-, 8- and 13-atomic) Cu clusters. The mechanism of the reaction was investigated by means of the molecular dynamics approach on the DFT level of theory. We have determined that there are two possible transition-state structures for the C-O bond dissociation-one where the reaction occurs on the wall of the cluster and the other occurring on the edge formed by two Cu atoms. The reaction depends also on the charge present on the Cu cluster that could be formed in the photoactivation and charge separation on the support. [ABSTRACT FROM AUTHOR]

Extinguishing forest fires is a critical issue for fire brigades; fire can spread throughout vast areas in a relatively short period of time. The studies presented in this paper describe the results of laboratory and field tests of new compositions of wetting agents for extinguishing wildland fires. The studies assessed the ability to penetrate surface fuels using 0.5 and 1% solution of wetting compositions. The penetration of the liquid through the layer of the loose rotting wood with solutions of obtained wetting agents was up to 68 times faster than with water. The absorption of water droplet was even 40 times slower in comparison to wetting agent solutions. Based on laboratory research, compositions that exhibit the best wetting properties were analysed in real conditions in field tests to assess their capacity to penetrate in surface fuels, their ability to make fire barriers and their efficiency in suppressing fires of soil cover and thickets. In tests performed in 4 m plots, the wetting compositions hold the flames from crossing a thin firebreak for up to three times longer periods than water. The results of the studies confirmed a significant increase in efficiency when new biodegradable wetting agents are employed to extinguish forest fires. [ABSTRACT FROM AUTHOR]

A noticeable improvement in the structural properties of Mn-Zn ferrite obtained by the solution combustion method was observed when the gel was additionally dried before self-combustion. The catalytic activity of thus prepared nanosized Mn-Zn ferrite has been also studied. The powders after combustion process were analyzed by X-ray diffraction and it was found that they possess pure spinel phase. The ferrite particles were agglomerated wherein powders obtained from the modified solution combustion method (gel additionally dried) characterized sponge-like structure and developed specific surface area. This ferrite material exhibits a significantly higher total acidity and it is reduced in the lower temperature. As a ferrite catalyst, prepared by the modified solution combustion method, possesses both acid and base centers, which allows to proceed the bimolecular ketonization reaction. The yield and selectivity of ketone increase with temperature with a maximum at 440 °C. Taking into account the obtained yield and selectivity results in the butan-1-ol conversion the MnZnFeO ferrite prepared in low temperature can be used as potential dehydrogenation catalyst. [ABSTRACT FROM AUTHOR]

One-layer protective coatings made up of SiO-AlO or SiO-AlO-CeO oxides were synthesized on a FeCrAl alloy substrate by the sol-gel method from sols containing tetraethyl orthosilicate, aluminum tri- sec-butoxide and cerium(III) 2,4-pentanedionate as the precursors. Coating solutions with the Si:Al:Ce molar ratio of 3:1:0, 3:1:0.1; 3:1:0.01, and 3:1:0.001 were used. The composition and morphology of the obtained gels were examined by TG/DSC, XRD, and SEM techniques. It was found that a small addition of cerium affected the morphology of the forming coatings and improved the FeCrAl alloy resistance to high-temperature oxidation (in air at T = 900 °C for t = 100 h). The oxidation of all the investigated samples conformed to the parabolic rate. The protection effectiveness of the one-layer coatings after 100 h of high-temperature oxidation was as high as 70 %. [ABSTRACT FROM AUTHOR]

The phase equilibria in the samarium(III) chloride-thallium chloride pseudobinary system were established by means of differential scanning calorimetry (DSC). The DSC investigations were performed on samples with different compositions in whole mole fraction x(SmCl) range. Experiments were carried out at heating and cooling rates ranging from 1 to 5 K min. This system has an eutectic character and includes three intermediate compounds: congruently melting TlSmCl ( T = 790 K) and incongruently melting TlSmCl ( T = 754 K) and TlSmCl ( T = 774 K). The dependence of heat capacity of TlSmCl on temperature has been measured for temperature range 300-900 K. The SmCl-TlCl pseudobinary system was optimized by CALPHAD method using the available experimental data. The dependencies of mixing enthalpy and mixing entropy on mole fraction x(SmCl) were estimated. The dependencies of formation Gibbs energy on temperature and temperature range of existence of all solid compounds have been calculated and discussed. [ABSTRACT FROM AUTHOR]

Phase diagram of HoBr-KBr pseudo-binary system was established by differential scanning calorimetry (DSC) method. This system includes two intermediate compounds: KHoBr and KHoBr. KHoBr undergoes a solid-solid phase transition at 689 K and melts congruently at 992 K, while KHoBr melts incongruently at 736 K. In the HoBr-KBr, system two eutectics occur. The eutectic mixture e melts at 875 K; its composition is x(HoBr) = 0.162. The other eutectic e with composition of x(HoBr) = 0.455 melts at 699 K. The heat capacity (solid and liquid phase) of congruently melting compound formed in this system was measured by DSC in the 300-1273 K range. The specific conductivity of HoBr-KBr liquid mixtures was measured down to temperatures below solidification over the entire composition range. The obtained results are discussed in term of possible complexes formation. [ABSTRACT FROM AUTHOR]

The phase equilibria occurring in the ErPO-KPO system were investigated by thermoanalytical, X-ray powder diffraction and FTIR methods. On the basis of the obtained results, its phase diagram was proposed. This system includes one intermediate compound, KErPO. This phosphate decomposes peritectically at about 1025 °C and occurs in two polymorphic forms; transformation β/α-KErPO proceeds at about 358 °C. The binary erbium end potassium diphosphate, KErPO, was obtained by the ceramic and modified Pechini methods. Structural properties were characterized by X-ray powder diffraction and FTIR spectroscopy. [ABSTRACT FROM AUTHOR]

The paper presents the results of our study on Pu, Pu, Pu, Am and Sr concentration in human bones carried out on a set of 88 individual samples of central Europe origin. Bone tissue samples were retrieved under surgery while introducing hip joint implants. The conducted surgeries tend to cover either southern or northeastern parts of Poland. While for the southern samples only global fallout was expected to be seen, a mixed global and Chernobyl fallout were to be reflected in the others. Alpha spectrometry was applied to obtain activity concentration for Pu, Pu, Am, while liquid scintillation spectrometry for Sr and mass spectrometry to receive Pu/Pu mass ratio. Surprisingly enough, and to the contrary to our expectations we could not see any significant differences in either Pu activity or Pu mass ratio between the studied populations. In both populations Chernobyl fraction proved marginal. The results on Sr and Am confirm similarities between the two examined groups. [ABSTRACT FROM AUTHOR]

Mn-Zn ferrites were obtained by the sol-gel autocombustion methods. The effect of the precursor used in the sol-gel autocombustion synthesis on the ferrite's microstructure was examined. The as-obtained powders were characterized by XRD, FTIR, SEM, and TG/DTA. All ferrite powders obtained from different organic precursors, after gel autocombustion, were pure spinel phase, without secondary phases. The average crystallite size, estimated from Scherrer equation, was the smallest for ferrite obtained from a mixture of fuels/precursors (citric acid and EDTA). This ferrite powder has sponge-like microstructure with large pores, but it is less agglomerated than the material obtained from glycine as the fuel. [ABSTRACT FROM AUTHOR]

The phase equilibria occurring in the ErPO-KPO system were investigated by the thermal analysis, FTIR, and X-ray powder diffraction methods. On the basis of obtained results, the related phase diagram is proposed. This system includes one intermediate compound, KEr(PO); the double phosphate melts incongruently at 1355 °C and occurs in two polymorphic forms; transformation β/α-KEr(PO) proceeds at 420 °C. The eutectic occurs at the composition of 58.5 wt% KPO, 41.5 wt% ErPO at 1317 °C. [ABSTRACT FROM AUTHOR]

This study had two objectives. First, to determine the prevalence of hollow (high-arched) and flat foot among primary school children in Cracow (Poland). Second, to evaluate the relationship between the type of medial longitudinal arch (MLA; determined by the Clarke's angle) and degree of fatness. The prevalence of underweight, overweight, and obesity was determined by means of IOTF cut-offs with respect to age and gender. A sample of 1,115 children (564 boys and 551 girls) aged between 3 and 13 years was analyzed. In all age groups, regardless of gender, high-arched foot was diagnosed in the majority of children. A distinct increase in the number of children with high-arched foot was observed between 7- and 8-year olds. Regardless of the gender, high-arched foot was more common among underweight children. In the group of obese children, the biggest differences were attributed to gender. High-arched foot was the most frequently observed among boys. In all gender and obesity level groups, the flat foot was more common among boys than among girls. Conclusions: High-arched foot is the most common foot defect among children 3-13 years old regardless of gender. Flat foot is least frequently observed in children 3-13 years old. A statistic correlation between MLA and adiposity is observed. Stronger correlation is observed among girls. [ABSTRACT FROM AUTHOR]

The organic-inorganic coordination polymer of the general formula {[NiL][Co(NCS)]} (where L = 5,12-dimethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene) has been synthesized and characterized by IR, UV-Vis, DSC/TG, DTA/TG/MS methods. The magnetic behaviour of this complex has also been investigated within the temperature range 1.8-300 K. The IR spectrum indicates the presence of bridging M-NCS-M′ ligands. The absorption bands of UV-Vis spectrum confirm that the coordination environment of nickel(II) ions changes from square planar for [NiL](ClO) to octahedral for {[NiL][Co(NCS)]}. The obtained compound is stable at room temperature, but within the range 246-282 °C decomposes in a three-stage process. The first step is associated with decomposition of the coordination polymer to the cationic [NiL] and anionic [Co(NCS)] units; the next two stages correspond to gradual decomposition of the macrocyclic ring. The value of molar magnetic susceptibility (χ T = 2.16 cm molK) indicates that the compound is paramagnetic. [ABSTRACT FROM AUTHOR]

Ce2O3-K2O-P2O5 ternary system has been investigated by thermoanalytical methods (DTA, DSC), powder X-ray diffraction, XPS and IR spectroscopy. The existence of three double potassium-cerium(III) phosphates has been confirmed and a new binary phosphate K4Ce2P4O15 has been found. Phase diagram and isothermal section at room temperature of the system Ce2O3-K2O-P2O5 have been presented. [ABSTRACT FROM AUTHOR]

Effect of the synthesis conditions of Pechini technique on crystallinity and purity of Na3Ce(PO4)2 compound was investigated. Nano-sized cerium-sodium phosphate obtained when EDTA was used as an additional chelating agent for Ln3+. The total enthalpy change of Na3Ce(PO4)2 phase transition was determined as 14.2±0.7 kJ mol−1 for sample synthesized by conventional solid-solid reaction. The phase transition process was confirmed to occur at 1060°C or in temperature range 920–1060°C depending on thermal treatment of powders. [ABSTRACT FROM AUTHOR]

Philadelphia-chromosome-negative chronic myeloproliferative disorders (Ph- CMPDs)--essential thrombocythemia (ET), chronic idiopathic myelofibrosis (CIMF), and polycythemia vera (PV)--may show clinical and morphological similarities, particularly at the early stages. The differential diagnosis of Ph- CMPDs is important due to their different treatment and prognosis. Cytological features of megakaryocytes are considered valuable in this differentiation. To establish an objective measure of megakaryocyte dysplasia in Ph- CMPDs, we performed computer-assisted morphometry of more than 4,000 cells from 20 cases of ET, 10 of CIMF, 10 of PV, and 10 controls. Megakaryocyte sets from three Ph- CMPDs differed significantly in respect to many planimetric parameters, but not a single shape or size parameter could have been used as a discriminative tool between the entities. However, the discriminant function analysis with the simultaneous assessment of 12 planimetric variables allowed for a proper classification of 20 of 20 ET, 10 of 10 PV, and 9 of 10 CIMF cases based solely on the morphometric features of megakaryocytes. Additionally, we identified certain new patterns of megakaryocytes specific for ET, PV, and CIMF, which, although not dominating in one Ph- CMPD, are unlikely to occur in two others. Objective measurements of megakaryocyte sizes and shapes may assist the diagnosis of Ph- CMPDs. [ABSTRACT FROM AUTHOR]

Philadelphia-chromosome-negative chronic myeloproliferative disorders (Ph− CMPDs)—essential thrombocythemia (ET), chronic idiopathic myelofibrosis (CIMF), and polycythemia vera (PV)—may show clinical and morphological similarities, particularly at the early stages. The differential diagnosis of Ph− CMPDs is important due to their different treatment and prognosis. Cytological features of megakaryocytes are considered valuable in this differentiation. To establish an objective measure of megakaryocyte dysplasia in Ph− CMPDs, we performed computer-assisted morphometry of more than 4,000 cells from 20 cases of ET, 10 of CIMF, 10 of PV, and 10 controls. Megakaryocyte sets from three Ph− CMPDs differed significantly in respect to many planimetric parameters, but not a single shape or size parameter could have been used as a discriminative tool between the entities. However, the discriminant function analysis with the simultaneous assessment of 12 planimetric variables allowed for a proper classification of 20 of 20 ET, 10 of 10 PV, and 9 of 10 CIMF cases based solely on the morphometric features of megakaryocytes. Additionally, we identified certain new patterns of megakaryocytes specific for ET, PV, and CIMF, which, although not dominating in one Ph− CMPD, are unlikely to occur in two others. Objective measurements of megakaryocyte sizes and shapes may assist the diagnosis of Ph− CMPDs. [ABSTRACT FROM AUTHOR]

The Grand Canonical Monte-Carlo (GCMC) method has been used to carry out simulations of the adsorption of n-heptane in models of naphtha-reforming catalysts. Models used in the study differed in the number and distribution of metal atoms—Pt and Sn. The number of adsorbed n-heptane molecules grows linearly with increasing number of metal atoms. The effect of Pt content on the adsorption of n-heptane molecules is most distinct at approximately 100 kPa and within the lower range of the temperatures investigated. In the models of bimetallic catalysts, the effect of the two metals is additive. [ABSTRACT FROM AUTHOR]

The behavior of the benzene--Pt--Sn/γ-Al2O3 catalytic system was simulated with the software Cerius2 from Accelrys Inc. The Grand Canonical Monte Carlo (GCMC) method was used to assess the adsorption isotherms under conditions of constant pressure and an equilibrium number of benzene molecules. With the results of GCMC simulation it was possible to locate the adsorption centers on the micropore surface at low temperature and a homogeneous benzene monolayer surface at elevated temperature. The results obtained with the GCMC method were then used to simulate the molecular dynamics of the catalytic system and to assess the coefficients of benzene diffusion. Elevated temperature was found to limit molecular motion across the micropore to a large extent. From the temperature-dependence plots of the diffusion coefficients it can be inferred that if the number of molecules is constant, the diffusion in the micropore is a molecular one. [ABSTRACT FROM AUTHOR]