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The microstructure features and hardness of AlSi9Cu3(Fe) die casting alloy was investigated in the presence of Zr addition. The cast alloys were undergone the solutionizing treatment 2 h at 500°C followed by artificial aging at 180°C for 5 h. Optical microscopy and electron micro-analyzer were used to study the formation of different intermetallic phases. The hardness was tested for all samples at 25°C. The results revealed that the intermetallic phase, based on (Al,Si)(Zr,Ti), forms when Zr is added in the investigated alloy, while the T6 heat treatment does not influence on the formation of Zr-bearing phase. Results also indicate that the hardness slightly increases in the AlSi9Cu3 alloy in as-cast state when Zr is added, while after T6 heat treatment increases by 50% in the alloy without Zr and by 61% in the alloy with Zr addition.

The AM60 alloy was thermodynamically examined using chemical analysis, thermodynamic calculation made by ThermoCalc program, “in situ” thermal analysis and differential scanning calorimetry (DSC), whereas the microstructure constituents were confirmed using optical and scanning electron microscopy (SEM). At the eutectic temperature of 437 °C the equilibrium solubility of Al in Mg is 12.6 wt. % Al. On the boundaries of the primary Mg grains the intermetallic compound of Al12Mg17 is precipitating according to the solvus line of the Mg-Al phase diagram. Solidification of the AM60 alloy has been investigated using “in situ” simple thermal analysis. The investigation of solidification has been taking place by evaluation of the cooling curves in connection with metallographic examinations, differential scanning calorimetry and thermodynamic calculations. All defects, nonmetallic inclusions and intermetallic compounds that occur in investigated AM60 alloy were identified.

Introduction: Although the inflammatory hypothesis in depression is more than two decades old, only some aspects are well researched. Transforming growth factor beta (TGF-β), which has a role as an anti-inflammatory and regulatory cytokine, is very poorly investigated in patients with major depressive disorder (MDD) who experienced childhood trauma. Objectives: Aim of our study was to analyze differences in serum concentrations of TGF-β between patients with MDD (with and without previous history of childhood abuse) and healthy controls, as well as to investigate possible predictors of TGF-β levels. Methods: Blood samples were obtained from 55 patients who fulfilled DSM-IV-R criteria for a current MDD episode without psychotic symptoms and 45 healthy controls, matched for age and gender. Participants were administered the Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HDRS) and the Childhood Trauma Questionnaire (CTQ). Serum TGF-β concentration was determined by enzyme-linked immunosorbent assay. Results: Concentration of TGF-β was significantly higher in patients compared to healthy controls and in those who reported experience of childhood abuse or neglect. Multiple logistic regressions showed a strong effect of CTQ total scores and duration of symptoms as predictors of TGF-β levels in patients. Conclusions: Conclusions: Childhood abuse as a predictor of TGF-β concentration in MDD patients could be an important missing puzzle in understanding immunological pathways and the role of cytokines in depression. ! [ABSTRACT FROM AUTHOR]

In the present work, the microstructure and grain refining performance of Ce on A380 alloy have been investigated, using thermal analysis, light microscopy with polarized light and scanning electron microscopy (SEM). The purpose was to study the influence of Ce addition on the formation of the microstructure. Ce changed the morphology of eutectic Al2Cu phase and caused small formation of primary crystals of αAl. Furthermore Ce phase was detected indicating quaternary phase AlCeCuSi (Al9Ce2Cu5Si3).