First proof of concept of remote attendance for future observation strategies between Wettzell (Germany) and Concepción (Chile)

Current VLBI observations are controlled and attended locally at the radio telescopes on the basis of pre-scheduled session files. Operations have to deal with system specific station commands and individual setup procedures. Neither the scheduler nor the correlator nor the data-analyst gets real-time feedback about system parameters during a session. Changes in schedules after the start of a session by remote are impossible or at least quite difficult. For future scientific approaches, a more flexible mechanism would optimize the usage of resources at the sites. Therefore shared-observation control between world-wide telescope s, remote attendance/control as well as completely unattended-observations could be useful, in addition to the classic way to run VLBI observations. To reach these goals, the Geodetic Observatory Wettzell in cooperation with the Max-Planck-Institute for Radio Astronomy (Bonn) have developed a software extension to the existing NASA Field System for remote control. It uses the principle of a remotely accessible, autonomous process cell as server extension to the Field System on the basis of Remote Procedure Calls (RPC). Based on this technology the first completely remote attended and controlled geodetic VLBI session between Wettzell, Germany and Concepción, Chile was successfully performed over 24 hours. This first test was extremely valuable for gathering information about the differences between VLBI systems and measuring the performance of internet connections and automatic connection re-establishments. During the 24h-session, the network load, the number of sent/received packages and the transfer speed were monitor ed and captured. It was a first reliable test for the future wishes to control several telescopes with one graphical user interface on different data transfer rates over large distances in an efficient way. In addition, future developments for an authentication and user role management will be realized within the upcoming NEXPReS project

A review of data on abundance, trends in abundance, habitat use and diet of ice-breeding seals in the Southern Ocean

The development of models of marine ecosystems in the Southern Ocean is becoming increasingly important as a means of understanding and managing impacts such as exploitation and climate change. Collating data from disparate sources, and understanding biases or uncertainties inherent in those data, are important first steps for improving ecosystem models. This review focuses on seals that breed in ice habitats of the Southern Ocean (i.e. crabeater seal, Lobodon carcinophaga; Ross seal, Ommatophoca rossii; leopard seal, Hydrurga leptonyx; and Weddell seal, Leptonychotes weddellii). Data on populations (abundance and trends in abundance), distribution and habitat use (movement, key habitat and environmental features) and foraging (diet) are summarised, and potential biases and uncertainties inherent in those data are identified and discussed. Spatial and temporal gaps in knowledge of the populations, habitats and diet of each species are also identified

Effective spin model for interband transport in a Wannier-Stark lattice system

We show that the interband dynamics in a tilted two-band Bose-Hubbard model can be reduced to an analytically accessible spin model in the case of resonant interband oscillations. This allows us to predict the revival time of these oscillations which decay and revive due to inter-particle interactions. The presented mapping onto the spin model and the so achieved reduction of complexity has interesting perspectives for future studies of many-body systems.Comment: 7 pages, 4 figure

Barriers and Facilitators to the Implementation of the Early-Onset Sepsis Calculator:A Multicenter Survey Study

Prior studies demonstrated the neonatal early-onset sepsis (EOS) calculator’s potential in drastically reducing antibiotic prescriptions, and its international adoption is increasing rapidly. To optimize the EOS calculator’s impact, successful implementation is crucial. This study aimed to identify key barriers and facilitators to inform an implementation strategy. A multicenter cross-sectional survey was carried out among physicians, residents, nurses and clinical obstetricians of thirteen Dutch hospitals. Survey development was prepared through a literature search and stakeholder interviews. Data collection and analysis were based on the Consolidated Framework for Implementation Research (CFIR). A total of 465 stakeholders completed the survey. The main barriers concerned the expectance of the department’s capacity problems and the issues with maternal information transfer between departments. Facilitators concerned multiple relative advantages of the EOS calculator, including stakeholder education, EOS calculator integration in the electronic health record and existing positive expectations about the safety and effectivity of the calculator. Based on these findings, tailored implementation interventions can be developed, such as identifying early adopters and champions, conducting educational meetings tailored to the target group, creating ready-to-use educational materials, integrating the EOS calculator into electronic health records, creating a culture of collective responsibility among departments and collecting data to evaluate implementation success and innovation results.</p

TANAMI - Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry

We present a summary of the observation strategy of TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry), a monitoring program to study the parsec-scale structure and dynamics of relativistic jets in active galactic nuclei (AGN) of the Southern Hemisphere with the Australian Long Baseline Array (LBA) and the trans-oceanic antennas Hartebeesthoek, TIGO, and O'Higgins. TANAMI is focusing on extragalactic sources south of -30 degrees declination with observations at 8.4 GHz and 22 GHz every ~2 months at milliarcsecond resolution. The initial TANAMI sample of 43 sources has been defined before the launch of the Fermi Gamma Ray Space Telescope to include the most promising candidates for bright gamma-ray emission to be detected with its Large Area Telescope (LAT). Since November 2008, we have been adding new sources to the sample, which now includes all known radio- and gamma-ray bright AGN of the Southern Hemisphere. The combination of VLBI and gamma-ray observations is crucial to understand the broadband emission characteristics of AGN and the nature of relativistic jets.Comment: Conference proceedings "2009 Fermi Symposium" eConf Proceedings C09112

Dual-frequency VLBI study of Centaurus A on sub-parsec scales

Centaurus A is the closest active galactic nucleus. High resolution imaging using Very Long Baseline Interferometry (VLBI) enables us to study the spectral and kinematic behavior of the radio jet-counterjet system on sub-parsec scales, providing essential information for jet emission and formation models. Our aim is to study the structure and spectral shape of the emission from the central-parsec region of Cen A. As a target of the Southern Hemisphere VLBI monitoring program TANAMI (Tracking Active Galactic Nuclei with Milliarcsecond Interferometry), VLBI observations of Cen A are made regularly at 8.4 and 22.3 GHz with the Australian Long Baseline Array (LBA) and associated telescopes in Antarctica, Chile, and South Africa. The first dual-frequency images of this source are presented along with the resulting spectral index map. An angular resolution of 0.4 mas x 0.7 mas is achieved at 8.4 GHz, corresponding to a linear scale of less than 0.013 pc. Hence, we obtain the highest resolution VLBI image of Cen A, comparable to previous space-VLBI observations. By combining with the 22.3 GHz image, which has been taken without contributing transoceanic baselines at somewhat lower resolution, we present the corresponding dual-frequency spectral index distribution along the sub-parsec scale jet revealing the putative emission regions for recently detected gamma-rays from the core region by Fermi/LAT. We resolve the innermost structure of the milliarcsecond scale jet and counterjet system of Cen A into discrete components. The simultaneous observations at two frequencies provide the highest resolved spectral index map of an AGN jet allowing us to identify multiple possible sites as the origin of the high energy emission.Comment: 5 pages, 3 figures (1 color); A&A, accepte

Platelet consumption during neonatal extracorporeal life support (ECLS)

This paper reports the results of a retrospective study of blood use and blood loss in 40 neonates during extracorporeal life support (ECLS). Immediately after onset of bypass 39±2.5ml platelets, 59.4±6.5ml packed red blood cells (PRBC) and 15.0±5.4ml fresh frozen plasma (FFP) per patient were needed. The average daily amount given per patient was 49.0±3.0ml of platelets and 48.0±3.4ml and 9.6±3.9ml of PRBC and FFP respectively. The 10 patients who had bleeding complications received 50.0±6.3ml/day of platelets compared to 49.0±3.4ml in the other patients. The majority of blood loss during the entire period of ECLS was from samples, averaging 43.0 ± 1.5ml/day. Neck wound drainage, 6.7±2.5ml/day per patient, lasted for the entire period.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68887/2/10.1177_026765919200700106.pd