EFFECT OF ANTIMONY DOPING ON PROPERTIES OF BARIUM TITANATE CERAMICS

Nanopowders of pure and antimony doped barium titanate were synthesized by polymeric precursors method. Sintering was performed at 1300 oC for 8 h. XRD analysis showed formation of cubic crystal structure in all nanopowders and tetragonal in ceramics. The influence of antimony concentration on structure change and microstructure development was analyzed. The significant dielectric properties modification as a consequence of antimony doping was noticed. The electrical resistivity measurements pointed out that antimony concentration influenced on materials change from insulator to semiconductor

Maternal Anti-Toxoplasma Treatment during Pregnancy Is Associated with Reduced Sensitivity of Diagnostic Tests for Congenital Infection in the Neonate

Neonatal diagnosis of congenital toxoplasmosis is based on a combination of serological and molecular tests. Maternal screening and treatment differ according to national policies and may impact the sensitivity of diagnostic methods in infants at birth. In this multicenter study, 115 neonates born to 61 treated (53%) and 54 (47%) untreated women were retrospectively included in three centers (France, Serbia, and the United States) to assess the impact of maternal anti-Toxoplasma treatment on the performance of neonatal workup at birth (neosynthesized anti-Toxoplasma IgM, IgA, and IgG and quantitative PCR [qPCR]) using univariate and multivariate approaches. Independently of the time of maternal seroconversion, the serological techniques were impacted differently by maternal treatment. The detection of IgM by immunosorbent agglutination assay (ISAGA) and Western blotting (WB) dropped from 90.7% and 88.2% in untreated neonates to 533% and 51.9% in treated neonates (P lt 0.05), whereas IgM enzyme-linked immunosorbent assay (ELISA) and IgA ISAGA were not significantly affected by maternal treatment. A 2-fold reduction in the sensitivity of neosynthesized IgG by WB was also observed in the case of treatment during pregnancy (37.7% versus 82.3%). Interestingly, the effect of treatment was shown to be duration dependent, especially for IgM detection, when the treatment course exceeded 8 weeks, whatever the therapy. The sensitivity of Toxoplasma PCR in blood was also lowered by maternal treatment from 39.1% to 23.2%. These results highlight that anti-Toxoplasma therapy during pregnancy may set back biological evidence of neonatal infection at birth and underline the need for a careful serological follow-up of infants with normal workup.This is the peer-reviewed version of the article: Guegan, H.; Štajner, T.; Bobić, B.; Press, C.; Olariu, R. T.; Olson, K.; Srbljanović, J.; Montoya, J. G.; Đurković-Đaković, O.; Robert-Gangneux, F. Maternal Anti-Toxoplasma Treatment during Pregnancy Is Associated with Reduced Sensitivity of Diagnostic Tests for Congenital Infection in the Neonate. Journal of Clinical Microbiology 2021, 59 (2). [https://doi.org/10.1128/JCM.01368-20

Chemical interaction, interfacial effect and the microstructural characterization of the induced zinc–aluminum–Solanum tuberosum in chloride solution on mild steel

In this study, we report the effect of Solanum tuberosum (ST) as a strong additive on the morphological interaction, wear, and hardness properties of electroplated zinc coating in chloride bath solutions. The structural and the mechanical behavior of the Zn–Al–ST coating were studied and compared with the properties of Zn coatings. Characterization of the electrodeposited coatings were carried out using scanning electron microscopy, energy dispersive spectrometer, AFM, and X-ray diffraction techniques. The adhesion between the coatings and substrate was examined mechanically using hardness and wear techniques. From the results, amorphous Zn–Al–ST coatings were effectively obtained by electrodeposition using direct current. The coating morphology was revealed to be reliant on the bath composition containing strong leveling additives. From all indications, ST content contribute to a strong interfacial surface effect leading to crack-free and better morphology, good hardness properties, and improved wear resistance due to the precipitation of Zn2Si and Zn7Al2Si3. Hence, addition of ST is beneficial for the structural strengthening, hardness, and wear resistance properties of such coatings

Subjektivna procjena kvalitete života (WHOQOL-BREFF) u odnosu na neuroticizam (Cornell index)

It is generally agreed that personality variables have a relatively consistent influence on the subjective estimation of different situations in everyday life and the way people react to them. The aim of this review was to summarise our previously published findings on the relationship between subjective estimation of one’s quality of life and the personality trait neuroticism-emotional stability. We used the WHO Quality of Life - BREF or SF-36 questionnaires for the assessment of the quality of life, Cornell Index for the assessment of neuroticism, and The Social Readjustment Rating Scale for the evaluation of common stressors. Our results have shown that more emotionally stable participants (lower neuroticism) perceive their life better in quality and are more satisfied with their work environment. In addition, our results support the findings from other studies that women have higher neuroticism and lower quality of life scores than men.Općenito se smatra kako varijable ličnosti imaju važnu ulogu u relativno dosljednom utjecaju na subjektivnu procjenu različitih situacija u svakodnevnom životu, kao i na reakcije na te situacije. Cilj ovoga preglednog članka bio je objediniti naše objavljene rezultate o odnosu između subjektivne procjene kvalitete života i crte ličnosti neuroticizam - emocionalna stabilnost. Upotrijebljeni su WHOQOL-BREF ili SF-36 upitnici za procjenu kvalitete života, Cornell indeks za procjenu neuroticizma i The Social Readjustment Rating Scale za evaluaciju uobičajenih stresora. Dobiveni rezultati pokazali su kako osobe s izraženijom emocionalnom stabilnošću (manjim neuroticizmom) percipiraju svoj život kvalitetnijim te su zadovoljnije svojom radnom okolinom. Također je u skladu s drugim objavljenim studijama nađeno kako žene postižu više rezultate na skalama neuroticizma od muškaraca te niže rezultate na upitnicima kvalitete života

Synthesis of ZrO2 Particles Reinforced ZA25 Alloy Composites by Compocasting Process

Microstructures and compressive properties of Zn25Al3Cu/ZrO2 particulate composites were studied. The composites were obtained by compocasting process through infiltration of 1 and 3 wt% ZrO2 particles of different size into the semi-solid melt of the base alloy. The influence of reinforcing particles size and quantity on microstructure and mechanical properties of the composites was examined. The composites have shown significant improvement of mechanical properties with respect to the base alloy. Increase in hardness and compressive yield strength of the composites was more expressed in the composites with coarse ZrO2 particles. (C) Koninklijke Brill NV, Leiden, 201

Microstructure and mechanical properties of Zn25Al3Cu based composites with large Al2O3 particles at room and elevated temperatures

Microstructures and compressive properties of Zn25Al3Cu alloy and Zn25Al3Cu/Al2O3 particulate composites with large reinforcing particles (250 mu m) were examined. The composites were obtained by the compocasting technique through infiltration of 3, 8 and 16 wt.% Al2O3 particles into the semi-solid metal matrix. The influence of temperature in the range from 70 to 170 degrees C on compressive yield strength of the matrix alloy (as-cast and thixocast Zn25Al3Cu alloy) and the composites was investigated. Above 70 degrees C compressive yield strength of all materials decreases, but the rate of decrease is different for the matrix alloy (as-cast and thixocast) and composites. It was found that the abrupt decrease in compressive yield strength of the matrix alloy occurred at temperatures higher than 70 degrees C, whereas composites retained relatively high values of compressive yield strength till the end of the testing temperature range regardless of the amount of reinforcing particles

Microstructure and mechanical properties of ZA27 alloy matrix composites

ddThe effect of Al2O3 and SiC particles on microstructure and strength (compression) of ZA27 (zinc-based alloy) was studied. Two composites were produced by compocasting process, i.e. particles of strengtheners were continuously added to the semi-solid melt which was vigorously stirred. The concentration and size of strengtheners were approximately the same, i.e. 3wt.% and 15 mum, respectively. Comparative investigations of microstructure (optical and scanning electron microscope) and compression strength (from room temperature to 170 degreesC) of composites and the corresponding as-cast alloy, produced by standard melting and casting process, were carried out. The dendritic structure was nearly completely removed by compocasting process, whereas a rather inhomogeneous distribution of strengtheners (particularly Al2O3) in the matrix was achieved. The strength of both composites was superior to that of as-cast alloy, the difference being greater with increase in temperature. The effect of Al2O3 and SiC particles on matrix strengthening was approximately the same.Trends in Advanced Materials and Processes, 3rd Yugoslov-Materials-Research-Society Conference, Sep 20-24, 1999, Herceg Novi, Yugoslavi