Strongly enhanced orbital moments and anisotropies of adatoms on the Ag(001) surface

We present ob initio calculations for orbital moments and anisotropy energies of 3d and 5d adatoms on the Ag(001) surface, based on density functional theory, including Brooks' orbital polarization (OP) term, and applying a fully relativistic Korringa-Kohn-Rostoker-Green's function method. In general, we find unusually large orbital moments and anisotropy energies, e.g., in the 3d series. 2.57 mu (B) and +74 meV for Co, and, in the 5d series, 1.78 mu (B) and +42 meV for Os. These magnetic properties are determined mainly by the OP and even exist without spin-orbit coupling

Fully relativistic calculation of magnetic properties of Fe, Co and Ni adclusters on Ag(100)

We present first principles calculations of the magnetic moments and magnetic anisotropy energies of small Fe, Co and Ni clusters on top of a Ag(100) surface as well as the exchange-coupling energy between two single adatoms of Fe or Co on Ag(100). The calculations are performed fully relativistically using the embedding technique within the Korringa-Kohn-Rostoker method. The magnetic anisotropy and the exchange-coupling energies are calculated by means of the force theorem. In the case of adatoms and dimers of iron and cobalt we obtain enhanced spin moments and, especially, unusually large orbital moments, while for nickel our calculations predict a complete absence of magnetism. For larger clusters, the magnitudes of the local moments of the atoms in the center of the cluster are very close to those calculated for the corresponding monolayers. Similar to the orbital moments, the contributions of the individual atoms to the magnetic anisotropy energy strongly depend on the position, hence, on the local environment of a particular atom within a given cluster. We find strong ferromagnetic coupling between two neighboring Fe or Co atoms and a rapid, oscillatory decay of the exchange-coupling energy with increasing distance between these two adatoms.Comment: 8 pages, ReVTeX + 4 figures (Encapsulated Postscript), submitted to PR

Genome Wide Association Identifies PPFIA1 as a Candidate Gene for Acute Lung Injury Risk Following Major Trauma

Acute Lung Injury (ALI) is a syndrome with high associated mortality characterized by severe hypoxemia and pulmonary infiltrates in patients with critical illness. We conducted the first investigation to use the genome wide association (GWA) approach to identify putative risk variants for ALI. Genome wide genotyping was performed using the Illumina Human Quad 610 BeadChip. We performed a two-stage GWA study followed by a third stage of functional characterization. In the discovery phase (Phase 1), we compared 600 European American trauma-associated ALI cases with 2266 European American population-based controls. We carried forward the top 1% of single nucleotide polymorphisms (SNPs) at p<0.01 to a replication phase (Phase 2) comprised of a nested case-control design sample of 212 trauma-associated ALI cases and 283 at-risk trauma non-ALI controls from ongoing cohort studies. SNPs that replicated at the 0.05 level in Phase 2 were subject to functional validation (Phase 3) using expression quantitative trait loci (eQTL) analyses in stimulated B-lymphoblastoid cell lines (B-LCL) in family trios. 159 SNPs from the discovery phase replicated in Phase 2, including loci with prior evidence for a role in ALI pathogenesis. Functional evaluation of these replicated SNPs revealed rs471931 on 11q13.3 to exert a cis-regulatory effect on mRNA expression in the PPFIA1 gene (p = 0.0021). PPFIA1 encodes liprin alpha, a protein involved in cell adhesion, integrin expression, and cell-matrix interactions. This study supports the feasibility of future multi-center GWA investigations of ALI risk, and identifies PPFIA1 as a potential functional candidate ALI risk gene for future research

Admixture Fine-Mapping in African Americans Implicates XAF1 as a Possible Sarcoidosis Risk Gene

Sarcoidosis is a complex, multi-organ granulomatous disease with a likely genetic component. West African ancestry confers a higher risk for sarcoidosis than European ancestry. Admixture mapping provides the most direct method to locate genes that underlie such ethnic variation in disease risk. We sought to identify genetic risk variants within four previously-identified ancestry-associated regions-6p24.3-p12.1, 17p13.3-13.1, 2p13.3-q12.1, and 6q23.3-q25.2-in a sample of 2,727 African Americans. We used logistic regression fit by generalized estimating equations and the MIX score statistic to determine which variants within ancestry-associated regions were associated with risk and responsible for the admixture signal. Fine mapping was performed by imputation, based on a previous genome-wide association study; significant variants were validated by direct genotyping. Within the 6p24.3-p12.1 locus, the most significant ancestry-adjusted SNP was rs74318745 (p = 9.4*10-11), an intronic SNP within the HLA-DRA gene that did not solely explain the admixture signal, indicating the presence of more than a single risk variant within this well-established sarcoidosis risk region. The locus on chromosome 17p13.3-13.1 revealed a novel sarcoidosis risk SNP, rs6502976 (p = 9.5*10-6), within intron 5 of the gene X-linked Inhibitor of Apoptosis Associated Factor 1 (XAF1) that accounted for the majority of the admixture linkage signal. Immunohistochemical expression studies demonstrated lack of expression of XAF1 and a corresponding high level of expression of its downstream target, X-linked Inhibitor of Apoptosis (XIAP) in sarcoidosis granulomas. In conclusion, ancestry and association fine mapping revealed a novel sarcoidosis susceptibility gene, XAF1, which has not been identified by previous genome-wide association studies. Based on the known biology of the XIAP/XAF1 apoptosis pathway and the differential expression patterns of XAF1 and XIAP in sarcoidosis granulomas, we suggest that this pathway may play a role in the maintenance of sarcoidosis granulomas

Orbital magnetism of transition metal adatoms and clusters on the Ag and Au(001) surfaces

We present ab initio calculations of the orbital moments and magnetocrystalline anisotropy energies for 3d, 4d, and 5d transition-metal adatoms and for some selected small clusters on the (001) surfaces of Ag and Au. The calculations are based on the local density approximation of density functional theory and apply a fully relativistic Koringa-Kohn-Rostoker Green's function method. Due to the reduced coordination of the adatoms and the weak hybridization with the substrate, we find fairly large orbital moments, in particular for the elements towards the end of the series. The general trend can be understood from a simple tight-binding model. The orbital moments are connected with very large anisotropy energies. While the orbital moments are on the Ag substrate somewhat larger than on Au, the magnetic anisotropy has about the same size for both substrates. Calculations for small clusters of Fe, Ru, and Os adatoms show, that due to interaction effects the orbital moments are strongly reduced, e.g., by 50% for the dimer atoms. The size of the reduction correlates well with the coordination number. Similar reductions also occur for the magnetic anisotropy energies

Identification of causes of occurence non-conforming products in terms of functioning of the supply chain

Companies by working with suppliers and customers create supply chains. In order to strengthen its competitive position they pay special attention to the quality of products, because it is important for buyers. To ensure the high quality of manufactured products, the functioning of production process should be controlled by the company which allows to identify the causes of abnormalities that cause the deterioration of the quality level of products and the reduction of the resulting wastes. The article presents the identification of causes of non-conforming products from the point of view of the functioning of the supply chain. The first part shows the link between reverse logistics and quality aspects in the supply chain. The second part presents the results of studies which aim is analysis of way of location non-conforming products and their causes in selected metallurgical company. For the analysis were used indicators: total non-conforming products, useful non-conforming products and indicator of scrap. The level of these indicators is planned and monitored by the company on a monthly and annual basis

Scanning tunneling spectra of impurities in the Fe(001) surface

We present ab initio calculations of scanning tunneling spectra for the Fe(001) surface and for 3d impurities in this surface. The calculations are performed by the full-potential Korringa-Kohn-Rostoker Green's-function method, and also partly by the full-potential linearized augmented-plane-wave method. For the clean Fe(001) surface we demonstrate that the correct tunneling spectrum is only obtained in a full potential treatment, while the atomic-sphere approximation yields incorrect results. For 3d impurities in the surface layer, peaks appear in the spectra due to surfacelike states localized on the impurity site. Our results can explain recent scanning tunneling microscopy experiments on Cr impurities in the Fe(001) surface. and predict that chemical identification is also possible for many other transition-metal impurities

Structure and directions of steel distribution based on selected company

W niniejszej pracy przedstawiono kierunki i strukturę dystrybucji asortymentu blach wybranego przedsiębiorstwa hutniczego. Analizę przeprowadzono na podstawie udziału poszczególnych rodzajów blach w sprzedaży oraz kierunków dystrybucji z uwzględnieniem wskaźnika reklamacji, jako podstawowego aspektu jakości produktów.This paper presents the trends and structure of distribution range of the steel company. The analysis was based on the share of individual product sheets in the sales and distribution directions, taking into account the complaints index as a primary aspect of the quality of products