Thermochemical properties and glass forming tendency modeling for the ternary Ge–Mn–Gd melts

Information on the thermochemical properties may be useful for predicting of the concentration regions of easy glass formation in multicomponent alloys. In present investigation the integral enthalpies of mixing for the Ge–Mn–Gd melts were determined for the entire concentration interval at 1830 K using the Redlich-Kister-Muggianu method. GFT values for binary and ternary alloys of this system were calculated. Size mismatch entropy was estimated within the frameworks of hard spheres model. On the basis of performed calculations the concentration regions in which the melts of the Ge–Mn–Gd system can demonstrate considerable tendency to easy glass formation were suggested

The enthalpies of mixing of ternary liquid Ag-Ca-Ge alloys

Partial and integral enthalpies of mixing of the ternary Ag–Ca–Ge melts were determined for the first time by the high-temperature isoperibolic calorimetry at 1300–1550 K. The experiments were performed for six sections with a constant ratio of two components up to the molar fraction of the third component equal to 0.3. The enthalpies of mixing in this ternary system are exothermic values which increase in absolute value from the Ag corner of the concentration triangle towards the constituent binary Ca–Ge system. The minimum value of the integral enthalpy of mixing was obtained for Ca0.6Ge0.4 composition of the Ca–Ge binary system (about –58.00 kJ mol–1). The enthalpies of mixing of the ternary Ag–Ca–Ge melts are calculated for the whole concentration triangle by the Redlich-Kister-Muggianu method, taking into account the term of specific ternary interaction defined from our experimental data. The topology of the isoenthalpies of mixing is determined

Thermochemical properties of liquid alloys along xCu/xSb= 0.2/08 section of the ternary Cu-Sb-Ce system

The enthalpies of mixing of liquid alloys of the ternary Cu–Sb–Ce system were studied by high-temperature calorimetry along the cross-section = 0.2/0.8. The composition dependence of these values were modelled using four "geometric" models and also the analytical method of Redlich–Kister–Muggianu. A comparison of the experimental data for the cross section  = 0.2/0.8 and simulated values of the enthalpies of mixing showed that the most suitable for describing the properties of liquid alloys of ternary Cu–Sb–Ce system is the Toop model

Calculation of thermodynamic properties of liquid Fe-Ln alloys

This paper presents the results of estimation of thermodynamic properties of binary Fe–Ln systems which characterized by small or moderate energy of component interaction in liquid state. The good agreement between enthalpies of mixing calculated in “surrounded atom” approximation and experimentally obtained enthalpies of mixing is observed for all investigated systems including Fe–Pr one, in which sign variable values of heat effects were determined. The method of estimation of excess Gibbs energies of liquid Fe–Ln alloys is proposed and the results of such estimation are given for a number of systems including those experimentally unexplored yet

Modelling thermodynamic properties of binary Cu–Eu and ternary Al–Cu–Eu melts

Model calculations of the whole set of thermodynamic properties of liquid alloys for the binary Cu–Eu and ternary Al–Cu–Eu systems have been performed. Authors used the ideal associated solution model (IAS model) for calculation of the entropies and excess Gibbs energies of mixing for these systems. The binaries were given as the Redlich-Kister polynomials. The thermodynamic properties for the ternary system are described using the Redlich-Kister-Muggianu formalism. A comparison of the surfaces of excess Gibbs energy and entropy of mixing for liquid Al–Cu–Eu alloys at 1350 K demonstrates that the ordering related to the formation of rather strong associates in the Al–Eu system significantly affects the concentration dependence of the excess Gibbs energy of mixing in the liquid phase at this temperature

Cuestiones actuales de los enfoques bancarios para la evaluación del riesgo de crédito de un prestatario sociedad anónima en condiciones de inestabilidad

El artículo está dedicado al tema de la evaluación del riesgo crediticio de un prestatario corporativo de un banco en las condiciones de la pandemia de coronavirus y sus consecuencias. Se ha esbozado la situación del sector bancario en las condiciones actuales, se han presentado las directrices del regulador para mejorar el sector bancario en el marco de un enfoque orientado al riesgo. Se ha puesto de manifiesto la necesidad de modernizar los métodos de cálculo del riesgo de crédito basados en el modelo de pérdidas esperadas, teniendo en cuenta la superposición del factor de fluctuaciones cíclicas de los sistemas económicos

Determinants of serum concentrations of perfluoroalkyl acids (PFAAs) in school children and the contribution of low-level PFAA-contaminated drinking water

Little is known about the demographic/life-style/physiological determinants explaining the variation of serum perfluoroalkyl acid (PFAA) concentrations in children. We identified significant determinants in children and investigated the influence of low-level PFAA-contaminated drinking water (DW) (<10 ng L−1 of single PFAAs) on serum concentrations. Four perfluorosulfonic acids (PFSAs) and 11 perfluorocarboxylic acids (PFCAs) were analyzed in serum from 5th grade children from 11 Swedish schools (N = 200; average age: 12 years) using liquid chromatography-tandem-mass-spectrometry. Data on demography and life-style/physiological factors were obtained by questionnaires. PFAA concentrations in raw and drinking water (DW) were obtained from the water works supplying DW to the schools. In multiple regression analyses school was the determinant contributing most to the variation in PFAA concentrations, with the lowest contribution for PFHpA (10%) and the highest for PFHxS (81%). Girls had lower adjusted mean concentrations of PFHxS, PFOS, PFNA and PFDA than boys, but a higher concentration of PFHxA. Girls reporting onset of menstruation had lower PFHxS and PFOA concentrations than other girls, suggesting menstrual bleeding elimination. Children born by mothers from less industrialized countries had lower mean concentrations of both PFSAs and PFCAs than children with mothers from highly industrialized countries, suggesting differences in early-life exposure. Life-style factors associated with paternal education levels appeared to influence PFAA concentrations differently than maternal education level. Already at an average DW PFHxS concentration of 2 ng L−1, children had a significantly higher adjusted mean serum PFHxS concentration than at an average DW concentration of <1.6 ng PFHxS L−1. Similar results were observed for PFOS and PFOA. The DW variable explained 16% (PFOA) to 78% (PFHxS) of the variation in serum PFAA concentrations, suggesting that low-level-contaminated DW is a significant source of exposure for children in Sweden. Although some of the associations, especially those with menstruation and maternal birth country, should be interpreted with extra caution due to the small size of the study, the results contribute to future work on identifying populations of children at risk of elevated PFAA exposures

Dibromidobis(3,5-dimethyl-1H-pyrazole-κN 2)cobalt(II)

In the mononuclear title complex, [CoBr2(C5H8N2)2], the CoII atom is coordinated by two N atoms from two monodentate 3,5-dimethyl­pyrazole ligands and two Br atoms in a highly distorted tetra­hedral geometry. In the crystal, the complex mol­ecules are linked by inter­molecular N—H⋯Br hydrogen bonds into chains along [101]. An intra­molecular N—H⋯Br hydrogen bond is also present

The Importance of Clinical and Biochemical Markers in the Diagnosis of Disorders of the Psychomotor and Physical Development of Children who Underwent Perinatal CNS Lesions

The purpose of this study was to evaluate the blood level of neurotrophic factors (S100 protein, nerve growth factor, L- homocysteine and angiotensin II) in the diagnosis of disorders of the psychomotor and physical development of children who underwent perinatal CNS lesions. A comprehensive approach to assessing the blood levels of neurotrophic factors, along with methods of neuroimaging in children in the first 6 months of the postnatal period, allows identification of the total result of multidirectional degenerative-reparative processes in the neurovascular components of CNS and construction of the diagnostically significant criteria of the severity of neuropathology, which determines the physical development of children in the first year of life

[Genome-wide association study of testes development indicators in roosters (Gallus gallus L.)] Полногеномные ассоциативные исследования показателей развития семенников у петухов (Gallus gallus L.)

Reproductive ability is one of the main indicators of the male breeding value that depends primarily on the functional state of testes cells. Male fertility is defined by complex physiological processes affecting the formation of mature germ cells, i.e., spermatozoa in the process of spermatogenesis. The forming and accumulation of germ cells occur in the seminiferous tubules of the testes, therefore the gonad development can serve as an indicator characterizing spermatogenesis and the reproductive potential of males. A number of studies on farm animals, including poultry, have shown the genetic determinacy of this trait, with identification of respective single nucleotide polymorphisms (SNPs) and genes determining the male gonad growth and development. In the present investigation, a genome-wide association study (GWAS) of the testes development parameters in roosters (Gallus gallus L.) of the F2 resource population were conducted. For the first time, new significant SNPs and candidate genes (р < 1.05½104) determining gonad growth and development in roosters were identified. The aim of the research was to seek SNPs and identify genes associated with testes growth parameters in roosters. The object of the study were F2 roosters from a model resource population (n = 115) that was obtained by interbreeding two breeds, Russian White and White Cornish. DNA was extracted from feather pulp using a commercial kit DNK Extran-2 (OOO NPF Sintol, Russia) in accordance with the manufacturer’s protocol. Genotyping was carried out using the medium-density Illumina Chicken 60K SNP iSelect BeadChip chip. At the age of 63 days, the experimental birds were slaughtered and the mass and morphometric indices of testes (length and thickness) were examined. Based on the obtained genotypic and phenotypic data, the GWAS analysis was performed in F2 resource population roosters using PLINK 1.9 software. The examined population was characterized by a high coefficient of variation in the measured indices, 96.1 % for the testes mass and 39.1 % for the linear measurements. The mass and linear measurements of the left testis were 5-14 % higher (р 0.05) compared to the right testis. The GWAS analysis revealed 36 significant SNPs (р < 1.05½104) associated with testes growth and development parameters in 63-day-old cockerels, in particular with the mass, length and thickness of the testes, 3, 26 and 7 SNPs, respectively. SNPs were localized on chromosomes GGA1, GGA3, GGA6, GGA7, GGA12, GGA15, and GGA18. A total of 156 genes were identified in the regions of the detected SNPs, including 16 genes that coincided with the positions of these SNPs. In particular, the latter were one gene (WNT7A) associated with the testis mass, 13 genes (LHFPL1, GALNT3, TMEM198, CACNA2D3, CCDC66, CACNA1D, DENND6A, CELSR3, WNT7A, IP6K2, ERC2, ABHD6, and DEPDC5) associated with the testis length, and three genes (ESR1, POLE, and RNFT2) associated with the testis thickness. These data can be used in genomic selection of roosters aimed at increasing their reproductive potential