The midwife factor in obstetric procedures and neonatal outcome

Aims. In the face of major tendency towards midwiferyled-care it was our purpose to investigate the extent of the influence of the midwife on the rates of obstetric procedures and perinatal outcome. Methods. 5384 consecutive deliveries at the Department of Obstetrics and Gynecology. University of Graz, were enrolled in the study. The following data were collected: mode of delivery, pH of umbilical artery, Apgar score. Firstly, data were investigated for interindividual differences and, secondly, for relationship with age of the midwife as a measure of experience. Results. Interindividual differences were significant for episiotomy rates (minimum: 31.6%; maximum 76.9%; p<0.001), forceps rates (minimum: 1.7%; maximum 11.1%;p=0.002) and pH of umbilical arteries (minimum: 7.21:maxinium: 7.28 p=0.001) but not for cesarean section rates and Apgar scores. Linear regression analysis was significant between age of midwives and pH of umbilical arteries (p<0.001: r=0.055) and for one-minute Apgar score (p=0.009; r=0.050) but not for episiotomy rates, cesarean section rates, forceps rates and five-minutes Apgar score. Conclusions. There are large interindividual differences in obstetric intervention rates which cannot be explained by the midwives' age. Provision of health care should be primarily determined by need and not by the personal characteristics of the health care provider, thus interindividual differences should be reduced and more often taken into account when analyzing any kind of data

Phase closure nulling of HD 59717 with AMBER/VLTI . Detection of the close faint companion

Aims: The detection of close and faint companions is an essential step in many astrophysical fields, including the search for planetary companions. A new method called "phase closure nulling" has been proposed for the detection of such faint and close companions based on interferometric observations when the system visibility amplitude is close to zero due to the large diameter of the primary star. We aim at demonstrating this method by analyzing observations obtained on the spectroscopic binary HD 59717. Methods: Using the AMBER/VLTI instrument in the K-band with ~1500 spectral resolution, we record the spectrally dispersed closures phases of the SB1 binary HD 59717 with a three-baseline combination adequate for applying phase closure methods. After a careful data reduction, we fit the primary diameter, the binary flux ratio, and the separation using the phase closure data. Results: We detect the 5-mag fainter companion of HD 59717 at a distance of 4 stellar radii from the primary. We determine the diameter of the primary, infer the secondary's spectral type and determine the masses and sizes of the stars in the binary system. This is one of the highest contrasts detected by interferometry between a companion and its parent star. Based on observations collected at the European Southern Observatory, Paranal, Chile, within the commissioning programme 60.A-9054(A)

Integrated optics for astronomical interferometry. I. Concept and astronomical applications

We propose a new instrumental concept for long-baseline optical single-mode interferometry using integrated optics which were developed for telecommunication. Visible and infrared multi-aperture interferometry requires many optical functions (spatial filtering, beam combination, photometric calibration, polarization control) to detect astronomical signals at very high angular resolution. Since the 80's, integrated optics on planar substrate have become available for telecommunication applications with multiple optical functions like power dividing, coupling, multiplexing, etc. We present the concept of an optical / infrared interferometric instrument based on this new technology. The main advantage is to provide an interferometric combination unit on a single optical chip. Integrated optics are compact, provide stability, low sensitivity to external constrains like temperature, pressure or mechanical stresses, no optical alignment except for coupling, simplicity and intrinsic polarization control. The integrated optics devices are inexpensive compared to devices that have the same functionalities in bulk optics. We think integrated optics will fundamentally change single-mode interferometry. Integrated optics devices are in particular well-suited for interferometric combination of numerous beams to achieve aperture synthesis imaging or for space-based interferometers where stability and a minimum of optical alignments are wished.Comment: 11 pages, 8 figures, accpeted by Astronomy and Astrophysics Supplement Serie

Astrophotonic micro-spectrographs in the era of ELTs

The next generation of Extremely Large Telescopes (ELT), with diameters up to 39 meters, will start opera- tion in the next decade and promises new challenges in the development of instruments. The growing field of astrophotonics (the use of photonic technologies in astronomy) can partly solve this problem by allowing mass production of fully integrated and robust instruments combining various optical functions, with the potential to reduce the size, complexity and cost of instruments. In this paper, we focus on developments in integrated micro-spectrographs and their potential for ELTs. We take an inventory of the identified technologies currently in development, and compare the performance of the different concepts. We show that in the current context of single-mode instruments, integrated spectrographs making use of, e.g., a photonic lantern can be a solution to reach the desired performance. However, in the longer term, there is a clear need to develop multimode devices to improve overall the throughput and sensitivity, while decreasing the instrument complexity.Comment: 9 pages. 2 figures. Proceeding of SPIE 9147 "Ground-based and Airborne Instrumentation for Astronomy V

Local pressure-induced metallization of a semiconducting carbon nanotube in a crossed junction

The electronic and vibrational density of states of a semiconducting carbon nanotube in a crossed junction was investigated by elastic and inelastic scanning tunneling spectroscopy. The strong radial compression of the nanotube at the junction induces local metallization spatially confined to a few nm. The local electronic modifications are correlated with the observed changes in the radial breathing and G-band phonon modes, which react very sensitively to local mechanical deformation. In addition, the experiments reveal the crucial contribution of the image charges to the contact potential at nanotube-metal interfaces

Identification of Cohesive Ends and Genes Encoding the Terminase of Phage 16-3

Cohesive ends of 16-3, a temperate phage of Rhizobium meliloti 41, have been identified as 10-base-long, 3′-protruding complementary G/C-rich sequences. terS and terL encode the two subunits of 16-3 terminase. Significant homologies were detected among the terminase subunits of phage 16-3 and other phages from various ecosystems

Computing the Least-core and Nucleolus for Threshold Cardinality Matching Games

Cooperative games provide a framework for fair and stable profit allocation in multi-agent systems. \emph{Core}, \emph{least-core} and \emph{nucleolus} are such solution concepts that characterize stability of cooperation. In this paper, we study the algorithmic issues on the least-core and nucleolus of threshold cardinality matching games (TCMG). A TCMG is defined on a graph $G=(V,E)$ and a threshold $T$, in which the player set is $V$ and the profit of a coalition $S\subseteq V$ is 1 if the size of a maximum matching in $G[S]$ meets or exceeds $T$, and 0 otherwise. We first show that for a TCMG, the problems of computing least-core value, finding and verifying least-core payoff are all polynomial time solvable. We also provide a general characterization of the least core for a large class of TCMG. Next, based on Gallai-Edmonds Decomposition in matching theory, we give a concise formulation of the nucleolus for a typical case of TCMG which the threshold $T$ equals $1$. When the threshold $T$ is relevant to the input size, we prove that the nucleolus can be obtained in polynomial time in bipartite graphs and graphs with a perfect matching

Shuttle flight pressure instrumentation: Experience and lessons for the future

Flight data obtained from the Space Transportation System orbiter entries are processed and analyzed to assess the accuracy and performance of the Development Flight Instrumentation (DFI) pressure measurement system. Selected pressure measurements are compared with available wind tunnel and computational data and are further used to perform air data analyses using the Shuttle Entry Air Data System (SEADS) computation technique. The results are compared to air data from other sources. These comparisons isolate and demonstrate the effects of the various limitations of the DFI pressure measurement system. The effects of these limitations on orbiter performance analyses are addressed, and instrumentation modifications are recommended to improve the accuracy of similar fight data systems in the future