766 research outputs found

    The serological Salmonella Monitoring in German pork production: the structure of the central database and preliminary results of a basic epidemiological report

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    Since 2002, the Qualitiäit und Srcherheit GmbH (QS GmbH) has earned out a serologrcal salmonella monrtonng in German finishrng pig herds. Thrs monitoring arms at reducing the risk of introducmg salmonella into the meat production charn caused by mfected slaughter pigs and to identify and to remove infection sources. For this purpose the farms are differentrated into three risk categories (I =low, II = mrddle, III = high) by their chance to introduce salmonella into the pork production cham All data generated withm the monitoring are entered mto the central database Qualiproo (Qualitype AG, Dresden)

    Influence of Surfactant-Mediated Interparticle Contacts on the Mechanical Stability of Supraparticles

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    [Image: see text] Colloidal supraparticles are micron-scale spherical assemblies of uniform primary particles, which exhibit emergent properties of a colloidal crystal, yet exist as a dispersible powder. A prerequisite to utilize these emergent functionalities is that the supraparticles maintain their mechanical integrity upon the mechanical impacts that are likely to occur during processing. Understanding how the internal structure relates to the resultant mechanical properties of a supraparticle is therefore of general interest. Here, we take the example of supraparticles templated from water/fluorinated oil emulsions in droplet-based microfluidics and explore the effect of surfactants on their mechanical properties. Stable emulsions can be generated by nonionic block copolymers consisting of a hydrophilic and fluorophilic block and anionic fluorosurfactants widely available under the brand name Krytox. The supraparticles formed in the presence of both types of surfactants appear structurally similar, but differ greatly in their mechanical properties. While the nonionic surfactant induces superior mechanical stability and ductile fracture behavior, the anionic Krytox surfactant leads to weak supraparticles with brittle fracture. We complement this macroscopic picture with Brillouin light spectroscopy that is very sensitive to the interparticle contacts for subnanometer-thick adsorbed layers atop of the nanoparticle. While the anionic Krytox does not significantly affect the interparticle bonds, the amphiphilic nonionic surfactant drastically strengthens these bonds to the point that individual particle vibrations are not resolved in the experimental spectrum. Our results demonstrate that seemingly subtle changes in the physicochemical properties of supraparticles can drastically impact the resultant mechanical properties

    Żużel stalowniczy, jako zamiennik kruszyw naturalnych stosowanych w mieszance asfaltowej

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    Even though electric arc furnace (EAF) steel slag has been classified as non-hazardous waste by its physical and chemical characteristics, and is possible to be disposed of at provided disposal sites without danger to the environment, this is rarely applied, because the permanent disposal of steel slag is highly expensive and requires a great area, and the valuable ingredients of steel slag are lost forever. The purpose of this paper was to improve the management of this type of non-hazardous industrial waste. Alongside with reducing the area intended for its disposal and increasing the technological benefit of re-using waste material, the final results of these tests should ensure the economic profit of producers, as well as achieve a sociological-ecological benefit due to the reduction of expenditure of natural mineral aggregates, simultaneously enhancing the sustainable development policies in metallurgy. A part of this research examines the possibilities of using EAF slag in other industries, with a special focus on using the slag as substitute for natural mineral aggregates in the production of asphalt mixtures in road construction. The paper presents the results of testing physical and mechanical properties of EAF slag coming from the regular production of unalloyed carbon steel in CMC Sisak, Croatia with the application of prior processing encompassing cooling the liquid slag by air, as well as quenching by water, grinding, magnetic separation, fragmentation and granulometric fractioning for the purpose of its application in technologies of producing asphalt mixtures. Comparison of test results between specimens of water- and air-cooled EAF slag and natural aggregates used in asphalt mixtures on highways and other top-class traffic load roads has demonstrated that the examined slag has qually good physical and mechanical properties, while it is significantly better in terms of resistance to polishing.Pomimo faktu, że żużel z elektrycznych pieców łukowych (EAF) do wytopu stali został sklasyfikowany jako odpad inny niż niebezpieczny w oparciu o charakterystykę fizyczną i chemiczną, i możliwe jest jego składowanie na odpowiednich składowiskach bez zagrożenia dla środowiska naturalnego, jest to rzadko stosowane, ponieważ stałe składowanie żużla jest bardzo kosztowne i wymaga dużych powierzchni, a cenne składniki żużla są tracone na zawsze. Celem pracy była poprawa zagospodarowania tego rodzaju odpadów przemysłowych. Wraz ze zmniejszeniem powierzchni przeznaczonej na składowanie żużla i zwiększeniem korzyści technologicznych z ponownego wykorzystania odpadów, ostateczne wyniki tych badań powinny zapewnić osiągnięcie zysku producentów, jak również osiągnięcia korzyści społeczno-ekologicznych ze względu na zmniejszenie zużycia naturalnych kruszyw mineralnych, a jednocześnie wzmocnienie polityki zrównoważonego rozwoju w hutnictwie. Część tych badań analizuje możliwości wykorzystania żużla EAF w innych gałęziach przemysłu, ze szczególnym naciskiem na wykorzystanie żużla jako substytut naturalnych kruszyw mineralnych w produkcji mieszanek mineralno-asfaltowych w budownictwie drogowym. W artykule przedstawiono wyniki badań fizycznych i mechanicznych właściwości żużla EAF pochodzącego z regularnej produkcji stali węglowej niestopowej w CMC Sisak, Chorwacja z zastosowaniem uprzedniego przetworzenia obejmującego chłodzenia ciekłego żużla w powietrzu, jak również chłodzenia wodą, rozdrabniania, separacji magnetycznej, rozdrobnienia i frakcjonowania w celu jego stsowania w technologii produkcji mieszanek mineralno-asfaltowych. Porównanie wyników badań próbek żużla chłodzonego wodą i chłodzonego powietrzem oraz kruszyw naturalnych stosowanych w mieszankach asfaltowych na autostradach i innych drogach o dużym obciążeniu ruchem wykazało, że badany żużel ma równie dobre właściwości fizyczne i mechaniczne, a jednocześnie jest znacznie lepszy pod względem odporności na ścieranie

    Comparative Modelling of the Spectra of Cool Giants

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    Our ability to extract information from the spectra of stars depends on reliable models of stellar atmospheres and appropriate techniques for spectral synthesis. Various model codes and strategies for the analysis of stellar spectra are available today. We aim to compare the results of deriving stellar parameters using different atmosphere models and different analysis strategies. The focus is set on high-resolution spectroscopy of cool giant stars. Spectra representing four cool giant stars were made available to various groups and individuals working in the area of spectral synthesis, asking them to derive stellar parameters from the data provided. The results were discussed at a workshop in Vienna in 2010. Most of the major codes currently used in the astronomical community for analyses of stellar spectra were included in this experiment. We present the results from the different groups, as well as an additional experiment comparing the synthetic spectra produced by various codes for a given set of stellar parameters. Similarities and differences of the results are discussed. Several valid approaches to analyze a given spectrum of a star result in quite a wide range of solutions. The main causes for the differences in parameters derived by different groups seem to lie in the physical input data and in the details of the analysis method. This clearly shows how far from a definitive abundance analysis we still are.Comment: accepted for publication in A&A. This version includes also the online tables. Reference spectra will later be available via the CD

    Coherent \pi^0 threshold production from the deuteron at Q^2 = 0.1 GeV^2/c^2

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    First data on coherent threshold \pi^0 electroproduction from the deuteron taken by the A1 Collaboration at the Mainz Microtron MAMI are presented. At a four-momentum transfer of q^2=-0.1 GeV^2/c^2 the full solid angle was covered up to a center-of-mass energy of 4 MeV above threshold. By means of a Rosenbluth separation the longitudinal threshold s wave multipole and an upper limit for the transverse threshold s wave multipole could be extracted and compared to predictions of Heavy Baryon Chiral Perturbation Theory.Comment: 7 pages, 7 figures, latex2

    Final State Interaction Effects in pol 3He(pol e,e'p)

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    Asymmetries in quasi-elastic pol 3He(pol e,e'p) have been measured at a momentum transfer of 0.67 (GeV/c)^2 and are compared to a calculation which takes into account relativistic kinematics in the final state and a relativistic one-body current operator. With an exact solution of the Faddeev equation for the 3He-ground state and an approximate treatment of final state interactions in the continuum good agreement is found with the experimental data.Comment: 11 pages, 6 figures, submitted to Phys. Lett. B, revised version, sensitivity study to relativity and NN-potential adde

    Measurement of the LT-asymmetry in \pi^0 electroproduction at the energy of the \Delta (1232) resonance

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    The reaction p(e,e'p)pi^0 has been studied at Q^2=0.2 (GeV/c)^2 in the region of W=1232 MeV. From measurements left and right of q, cross section asymmetries \rho_LT have been obtained in forward kinematics \rho_LT(\theta_\pi^0=20deg) = (-11.68 +/- 2.36_stat +/- 2.36_sys)$ and backward kinematics \rho_LT(\theta_\pi^0=160deg) =(12.18 +/- 0.27_stat +/- 0.82_sys). Multipole ratios \Re(S_1+^* M_1+)/|M_1+|^2 and \Re(S_0+^* M_1+)/|M_1+|^2 were determined in the framework of the MAID2003 model. The results are in agreement with older data. The unusally strong negative \Re(S_0+^* M_1+)/|M_1+|^2 required to bring also the result of Kalleicher et al. in accordance with the rest of the data is almost excluded.Comment: 7 pages, 7 figures, 4 tables. Changed content. Accepted for publication in EPJ

    Truncating mutations in the Wilson disease gene ATP7B are associated with very low serum ceruloplasmin oxidase activity and an early onset of Wilson disease

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    <p>Abstract</p> <p>Background</p> <p>Mutations in the gene ATP7B cause Wilson disease, a copper storage disorder with a high phenotypic and genetic heterogeneity. We aimed to evaluate whether 'severe' protein-truncating ATP7B mutations (SMs) are associated with low serum ceruloplasmin oxidase activities and an early age of onset when compared to missense mutations (MMs).</p> <p>Methods</p> <p>The clinical phenotype of 59 genetically confirmed WD patients was analyzed retrospectively. Serum ceruloplasmin was measured by its oxidase activity with <it>o</it>-dianisidine dihydrochloride as substrate and immunologically.</p> <p>Results</p> <p>Thirty-nine patients had two MMs, 15 had the genotype SM/MM, and 5 patients had two SMs on their ATP7B alleles. Enzymatic and immunologic serum ceruloplasmin levels differed significantly between the three groups (P < 0.001 and P < 0.01, respectively). The lowest levels were measured in patients with two SMs (0.0 U/L; IQR, 0.0-0.0 U/L and 0.02 g/L; IQR, 0.01-0.02 g/L, respectively) and the highest in patients with two MMs (17.8 U/L; IQR, 5.8-35.1 U/L and 0.11 g/L; IQR,0.10-0.17 g/L, respectively). The age of onset was also significantly different between the three patient groups (P < 0.05), with SM/SM patients showing the earliest onset (13 years; IQR, 9-13 years) and patients with two MMs showing the latest onset (22 years; IQR, 14-27 years). By ROC curve analysis a ceruloplasmin oxidase level ≤ 5 U/L can predict the presence of at least one SM with a sensitivity of 80% and a specificity of 79.5%.</p> <p>Conclusions</p> <p>In our German study cohort truncating ATP7B mutations were associated with lower ceruloplasmin serum oxidase levels and an earlier age of onset when compared to MMs. Measurement of serum ceruloplasmin oxidase might help to predict presence of truncating ATP7B mutations and might facilitate the mutation analysis.</p
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