Morphology and Chemical Composition of Magnetic Particles Separated from Coal Fly Ash

Iron and other metal compounds are the materials that often appear in coal seams, because they also appear as a component of former organic matter in coal rocks. Although iron is the dominant element in coal rocks, other metals such as titanium, lead, cobalt, nickel, and copper are also present. In this study, the properties of magnetic particles of a size between 1 and 20 µm of globular structure and iron containing, were separated from coal fly ash, and studied using a scanning electron microscopy, energy disperse spectroscopy, and X-ray diffraction spectroscopy. The investigations were comprised of micrographs of the structure of these particles, their elemental composition, and phase analysis.     

New Graphene Composites for Power Engineering

Intensive research is underway worldwide to develop new conductive materials for applications in the power industry. Such tests aim to increase the electrical conductivity of materials for conductors and cables, thus increasing the current carrying capacity of the line and reducing the loss of electricity transmission. The scientific discovery of recent years, graphene, one of the allotropic types of carbon with very high electrical and thermal conductivity and mechanical strength, creates great opportunities for designing and producing new materials with above-standard operational properties. This project concentrates on developing technology for manufacturing aluminum-graphene and copper-graphene composites intended to be used to produce a new generation of power engineering conductors. In particular, we present the results of the research on the mechanical synthesis of aluminum-graphene and copper -graphene composites, as well as the results of the electric, mechanical, and structural properties of rods obtained after the extrusion process and wires after the drawing process.     

New dinuclear zinc(ii) complexes with Schiff bases obtained from o-phenylenediamine and their application as fluorescent materials in spin coating deposition

Two Zn(ii) complexes, K1 and K2, obtained from the template reaction of zinc(ii) acetate dihydrate with o-phenylenediamine and 2-hydroxy-5-methylisophthalaldehyde (K1) or 2-hydroxy-5-tert-butyl-1,3-benzenedicarboxaldehyde (K2), respectively, were characterized by X-ray crystallography, spectroscopic (UV-vis, fluorescence and IR), and thermal methods. In the complex [Zn₂(MeO)_1.4(OH)_0.6(L1)]·2H₂O K1, there are two binding sites in the macrocyclic ligand and they are occupied by zinc(ii) cations found in slightly distorted square pyramidal environment. The zinc(ii) cations are connected by slightly asymmetric oxo bridges with a Zn1–O14–Zn1[−x, −y + 1, −z + 1] angle of 104.8(2)°. In the dimer [Zn₂(CH₃COO)₂(L2)]·2EtOH K2, there are two crystallographically independent binding sites both occupied by zinc(ii) cations. There is a significant difference between both complexes, since in K1 only one site is independent and the second is occupied due to the application of symmetry rules, and the geometry of both sites is identical. Thin layers of the obtained Zn(ii) complexes were deposited on Si(111) by the spin coating method and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), fluorescence spectroscopy and ellipsometry. In the non-absorbing range, the value of the refractive index exhibits normal dispersion between 1.8 and 2.1 for K1_1–K1_3; and between 2.3 and 2.6 for the K2 series of samples established for long wavelengths (longer than 500 nm). The Zn(ii) complexes and their thin layers exhibited fluorescence between 534–573 nm and 495–572 nm for the compounds and the layers, respectively. The highest quantum yield of fluorescence was achieved for K2 in benzene and in the solid state ϕ = 0.78 and 0.58, respectively. The influence of the solvent polarity on the fluorescence properties of the obtained complexes was studied. Additionally, DFT calculations were performed to explain the structures and electronic spectral properties of the complexes.

Tin fluorescent materials were obtained using a spin coating method.     

A 2017 update: Challenging the cosmetic procedural delay following oral isotretinoin therapy

For decades it has been widely accepted that elective procedures should be delayed for at least 6-months following completion of isotretinoin therapy. However, numerous 2017 publications demonstrate the need for change in best practice. The evidence has yet to be succinctly summarized in a single article or in a stand-alone quick reference algorithm for physicians. This article’s review of all 2017 publications confirms that the 6-month delay is not necessary for all procedures and provides a simple algorithmic approach to summarize the updated recommendations for procedural delay of cosmetic procedures following systemic isotretinoin therapy. This is a useful tool for clinicians and allows patients to receive the most appropriate and timely cosmetic therapy to minimize the psychosocial impact of the skin condition.     

Factor analysis of the WISC and WISC-R: A Polish comparison

The factor structures of the WISC and WISC-R were secured for a group of Polish fourth-grade students (N = 30). Consistent with American findings, the WISC Verbal, Performance, and Full Scale IQs were higher than those on the WISC-R. On both measures, factor results favor the two-factor solution, which approximates Wechsler's Verbal and Performance scales. A third factor, which failed to simulate Freedom from Distractibility, accounted for approximately 10% of the explained variance. On this factor, Coding was heavily weighted, but Arithmetic and Digit Span loadings ranged from modest to negative. Results provide support for the application of the Wechsler instruments in cross-cultural settings and for interpreting the third factor according to the dynamics of specific cultures.     

Circulating endothelial cells in essential thrombocythemia and polycythemia vera: correlation with JAK2-V617F mutational status,angiogenic factors and coagulation activation markers

Angiogenesis plays an important role in the biology of hematological malignancies, including essential thrombocythemia (ET) and polycythemia vera (PV). Some data suggests that it has a role in the pathogenesis of thrombosis, the major clinical problem in ET and PV. The number of different subpopulations of circulating endothelial cells (CECs), plasma levels of vascular endothelial growth factor (VEGF), soluble vascular endothelial growth factor receptor 1 and 2 (sVEGFR-1,2) and placenta growth factor (PlGF) were determined in 30 patients with ET and 16 patients with PV. Correlations between angiogenesis and JAK2-V617F mutational status, risk factors for thrombosis and coagulation activation markers were also assessed. The number of CEC subpopulations, were markedly higher in ET and PV patients, irrespective of JAK2-V617F status, when compared to the control group. The median values of activated CECs were markedly higher in PV patients with WBC >8.7 (×10⁹/l). Significantly higher VEGF plasma levels were found in ET patients and a similar trend was seen in PV patients in relation to healthy volunteers. The plasma levels of sVEGFR-1 were significantly higher, and PlGF levels markedly lower, in the ET and PV group than in controls. Our study also demonstrated markedly increased levels of D-dimer and TAT complexes in the patient groups. In conclusion, we found that angiogenesis, as measured by CEC numbers, is increased in ET and PV patients regardless of JAK2-V617F mutational status. Our results demonstrated that angiogenic cytokines interact with known thrombotic risk factors. We confirmed the coagulation activation in ET and PV patients but found no differences in levels of coagulation activation markers in relation to JAK2-V617F mutational status.     

Epistatic relationship between the cancer susceptibility genes CHEK2 and p27.

We studied the effects of p27 and CHEK2 variants on prostate and colon cancer risk in a case-control study. Modest effects on prostate cancer risk were observed for both CHEK2 missense and truncating variants. However, the excess cancer risk was restricted to the subgroup of men who were homozygous for the VV genotype in codon 109 of the p27 gene. Among men with the VV p27 genotype, the odds ratios associated with truncating and missense CHEK2 mutations were 3.1 (P < 0.0001) and 1.9 (P < 0.0001), respectively. Among men with other p27 genotypes (GG and VG), the odds ratios were 1.5 and 1.2 for truncating and missense CHEK2 mutations, respectively, and were not statistically significant. The interaction between CHEK2 and p27 was confirmed in a group of patients with colon cancer. Thus, it seems that the clinical expression of CHEK2 variant alleles on prostate and colon cancer risk may be restricted to individuals with a specific genotype (VV) of the p27 gene. Two-gene models provide numerous challenges for gene identification and cancer risk assessment.     

Classical Prognostic Factors for Survival and Loco-Regional Control in Breast Cancer Patients Treated with Radical Mastectomy Alone

A retrospective analysis of clinical and pathological prognostic factors was performed in 1 068 breast cancer patients treated with radical mastectomy alone in 1952-1980. Three endpoints were considered: 10-year survival, 10-year disease-free survival and 10-year loco-regional relapse-free survival. Both univariate and multivariate analyses confirmed the prognostic significance of tumour size, histological type and grade (Bloom classification) and involvement of axillary nodes for all three endpoints. Additionally, young age appeared to be a significant risk factor for loco-regional disease-free survival. Prognostic subgroups were defined by the use of 3 main indicators. In node negative patients with T1 tumours the prognosis seemed to be good regardless of histological grade (80-90% 10-year disease-free survival), in T2 tumours the survival was significantly dependent on histological type and grade. In node positive patients increasing number of involved nodes and higher histological grade had an independent adverse effect on all three endpoints. The study demonstrates that classical, commonly available prognostic factors clearly distinguish subgroups with different prognosis, which may be helpful when deciding on the use of adjuvant local and/or systemic therapies.     

The effect of monocytes on early activation of lymphocytes T among children with idiopathic uveitis

PURPOSE: We have investigated T Lymphocytes ability for CD69 molecule induction in presence and absence of monocytes in idiopathic uveitis. MATERIAL AND METHODS: Twenty-five children with idiopathic uveitis were studied. The control group consisted of 12 healthy children. Peripheral blood mononuclear cells (PBMCs) were isolated from heparinised venous blood, by density gradient centrifugation. CD69 expression was cytometrically assessed on freshly isolated and cultured T lymphocytes. RESULTS: CD69 expression on freshly isolated peripheral blood T lymphocytes was low in both studied groups. LPS-stimulated monocytes added to cultures of T lymphocytes induced increase in CD69 expression but significantly lower in children with idiopathic uveitis compare to healthy children.