Infrared-Faint Radio Sources are at high redshifts

Context: Infrared-Faint Radio Sources (IFRS) are characterised by relatively high radio flux densities and associated faint or even absent infrared and optical counterparts. The resulting extremely high radio-to-infrared flux density ratios up to several thousands were previously known only for High-redshift Radio Galaxies (HzRGs), suggesting a link between the two classes of object. Prior to this work, no redshift was known for any IFRS in the Australia Telescope Large Area Survey (ATLAS) fields which would help to put IFRS in the context of other classes of object, especially of HzRGs. Aims: This work aims at measuring the first redshifts of IFRS in the ATLAS fields. Further, we test the hypothesis that IFRS are similar to HzRGs, as higher-redshift or dust-obscured versions of these massive galaxies. Methods: A sample of IFRS was spectroscopically observed using the Focal Reducer and Low Dispersion Spectrograph 2 (FORS2) at the Very Large Telescope (VLT). The data were calibrated based on the Image Reduction and Analysis Facility (IRAF) and redshifts extracted. This information was then used to calculate rest-frame luminosities, and to perform the first spectral energy distribution modelling of IFRS based on redshifts. Results: We found redshifts of 1.84, 2.13, and 2.76, for three IFRS, confirming the suggested high-redshift character of this class of object. These redshifts as well as the resulting luminosities show IFRS to be similar to HzRGs. We found further evidence that fainter IFRS are at even higher redshifts. Conclusions: Considering the similarities between IFRS and HzRGs substantiated in this work, the detection of IFRS, which have a significantly higher sky density than HzRGs, increases the number of Active Galactic Nuclei in the early universe and adds to the problems of explaining the formation of supermassive black holes shortly after the Big Bang.Comment: 7 pages, 4 figures; version in prin

Generalised partially linear regression with misclassified data and an application to labour market transitions

We consider the semiparametric generalised linear regression model which has mainstream empirical models such as the (partially) linear mean regression, logistic and multinomial regression as special cases. As an extension to related literature we allow a misclassified covariate to be interacted with a nonparametric function of a continuous covariate. This model is tailormade to address known data quality issues of administrative labour market data. Using a sample of 20m observations from Germany we estimate the determinants of labour market transitions and illustrate the role of considerable misclassification in the educational status on estimated transition probabilities and marginal effects

Leather Shaving – A New Approach for Understanding the Shaving Process

Content: The shaving process is one of the most important steps in leather production. However, the underlying principles and mechanisms are not yet fully understood. Generally, the successful performance of the shaving process is based on long-time experience, and the tanneries rather optimize the preceding process steps than change the shaving parameters. In a current research project the research partners (Heusch GmbH, TU Dresden and FILK gGmbH) have united their expertise in order to understand the interaction between the shaving blade and the semi-finished leather (wet-blue or wet-white). The objective of the project is to gain more insight into the physics of shaving and to create a background of knowledge, which will be the technical base for developing novel and more effective shaving blades. Heusch presents the advantages of a novel serrated shaving blade. In comparison with the standard design an serrated blade yields higher shaving accuracy and uniform thickness of the hides. Stretching forces along the dorsal line of the hides are reduced, which avoids structural damage. Marginal hide regions are less frayed, thus increasing the usable surface area. The small size and compact form of the shavings are advantageous for recycling and disposal. Exploiting these advantages combined with an optimized grinding process, the user can increase the lifetime of the serrated blades. Based on these experiences there is an urgent need to thoroughly understand the physical cutting processes which take place during the shaving step. In the current research project an experimental test station is designed which is intended to simulate the shaving process in a simplified setting as a cutting procedure of a blade into a leather surface. This test station will enable the variation of material, geometry and configuration of the blade as well as the measurement of forces emerging during cutting at the blade and the leather surface, which emerge during cutting. The registered data shall provide information on the question, how the cutting forces depend on technological parameters, like blade material, geometry, configuration, cutting speed, leather moisture or tanning method. Based on the knowledge of these relationships novel, even more effective shaving blades can be developed. In a second approach the cutting process of a single leather fibre will be simulated virtually on a microscale level. The goal is the understanding of the interaction of a moving metal blade with a flexible, unilaterally fixed leather fibre. The simulation is supposed to yield data on cutting speed and fibre behaviour under conditions which are experimentally difficult to access. Take-Away: The physical basics of the shaving process are not yet fully understood. The presented research project aims at the understanding of the interaction between shaving blade and leather fibres during the shaving process. The approach in the project is to model the cutting procedure in a simplified experimental test station and in a computational simulation model

Evaluasi Cepat Struktur Portal Beton Bertulang terhadap Gempa

Earthquakes from 2004 to 2009 in Indonesia has resulted in many deaths and the collapse of the building. The American Society of Civil Engineers (ASCE) with the Federal Emergency Management Agency (FEMA) has published FEMA 310 as a handbook for seismic evaluation of buildings. FEMA 310 evaluation includes evaluation of phase one, two and three. Evaluation of phase one (tier 1) using a checklist of structural, non-structural, region of low sismicity and also geologic site hazard and foundation. Evaluation of the second phase (tier 2) is a linear analysis for structures such as static equivalence analysis and dynamic. Evaluation of the third stage (tier 3) is non- linear analysis of such a pushover. If the evaluation phase of the assessment does not meet the criteria, then it should proceed to the second phase, as well as for further evaluation. The building is located in the city of Pekanbaru that is reviewed and evaluated up to the second phase. Calculation of seismic shear force have used seismic hazard map of Indonesia has been published in 2010. This is one step to improve the performance of structures to resist earthquakes, it is expected that this will reduce structural damage and avoid loss of life. The results of the evaluation phase one (tier 1) that has been conducted shows that the buildings that were reviewed non- compliant for weak story and soft story. Evaluation of the second phase (tier 2) shows that all the columns in buildings were able to bear the load, while some beam were over strength, however both of building can be declared the buildings are safe against earthquakes (compliant)

Multi-source self-calibration: Unveiling the microJy population of compact radio sources

Context. Very Long Baseline Interferometry (VLBI) data are extremely sensitive to the phase stability of the VLBI array. This is especially important when we reach {\mu}Jy r.m.s. sensitivities. Calibration using standard phase referencing techniques is often used to improve the phase stability of VLBI data but the results are often not optimal. This is evident in blank fields that do not have in-beam calibrators. Aims. We present a calibration algorithm termed Multi-Source Self-Calibration (MSSC) which can be used after standard phase referencing on wide-field VLBI observations. This is tested on a 1.6 GHz wide-field VLBI data set of the Hubble Deep Field-North and the Hubble Flanking Fields. Methods. MSSC uses multiple target sources detected in the field via standard phase referencing techniques and modifies the visibili- ties so that each data set approximates to a point source. These are combined to increase the signal to noise and permit self-calibration. In principle, this should allow residual phase changes caused by the troposphere and ionosphere to be corrected. By means of faceting, the technique can also be used for direction dependent calibration. Results. Phase corrections, derived using MSSC, were applied to a wide-field VLBI data set of the HDF-N comprising of 699 phase centres. MSSC was found to perform considerably better than standard phase referencing and single source self-calibration. All detected sources exhibited dramatic improvements in dynamic range. Using MSSC, one source reached the detection threshold taking the total detected sources to twenty. 60% of these sources can now be imaged with uniform weighting compared to just 45% with standard phase referencing. The Parseltongue code which implements MSSC has been released and made publicly available to the astronomical community (https://github.com/jradcliffe5/multi_self_cal).Comment: 7 pages, 4 figures, accepted to A&

Evidence for multiple structural genes for the γ chain of human fetal hemoglobin

A sequence with a specific residue at each position was proposed for the γ chain of human fetal hemoglobin by Schroeder et al. (1) after a study in which hemoglobin from a number of individual infants was used. We have now examined in part the fetal hemoglobin components of 17 additional infants and have observed that position 136 of the γ chain may be occupied not only by a glycyl residue, as previously reported, but also by an alanyl residue

Sozialstationen für Berlin

Soziale Notwendigkeit, Konzepte, Modelle und Finanzierung von Einrichtungen zur ambulanten Sozial- und Gesundheitspflege (Sozialstationen

Krebsregister und das Problem der Verhältnismäßigkeit: zur Situation der Krebsepidemiologie in der Bundesrepublik

This paper presents a survey of cáncer registries in Germany, their types, purposes and history, and discusses the problems of cáncer registration: medical confidentiality, data protection, extent of registration, effort-benefit ratio and legal regulation