Common problems in the design and construction of membrane structures

This paper presents and discusses common problems frequently encountered in the design and construction of membrane structures. Most of these problems can be avoided by careful design and preparation, which would take into account intermediate assembly and erection conditions. The following points should be considered, by assuring that: Realistic load assumptions are made, if necessary, with supporting load tests Individual fields are not too large Pre-assembly damage and kinks are avoided Slippage from snow, if possible, is avoided When parallel to design, manufacture and assembly, a construction supervisor is tasked with reviewing and supervising all the stages, major damage can be avoided

Analysing Timelines of National Histories across Wikipedia Editions: A Comparative Computational Approach

Portrayals of history are never complete, and each description inherently exhibits a specific viewpoint and emphasis. In this paper, we aim to automatically identify such differences by computing timelines and detecting temporal focal points of written history across languages on Wikipedia. In particular, we study articles related to the history of all UN member states and compare them in 30 language editions. We develop a computational approach that allows to identify focal points quantitatively, and find that Wikipedia narratives about national histories (i) are skewed towards more recent events (recency bias) and (ii) are distributed unevenly across the continents with significant focus on the history of European countries (Eurocentric bias). We also establish that national historical timelines vary across language editions, although average interlingual consensus is rather high. We hope that this paper provides a starting point for a broader computational analysis of written history on Wikipedia and elsewhere

Transport, properties, and life cycles of mesoscale eddies in the eastern tropical South Pacific

The influence of mesoscale eddies on the flow field and the water masses, especially the oxygen distribution of the eastern tropical South Pacific, is investigated from a mooring, float, and satellite data set. Two anticyclonic (ACE1/2), one mode-water (MWE), and one cyclonic eddy (CE) are identified and followed in detail with satellite data on their westward transition with velocities of 3.2 to 6.0cms−1 from their generation region, the shelf of the Peruvian and Chilean upwelling regime, across the Stratus Ocean Reference Station (ORS;  ∼ 20°S, 85°W) to their decaying region far west in the oligotrophic open ocean. The ORS is located in the transition zone between the oxygen minimum zone and the well oxygenated South Pacific subtropical gyre. Velocity, hydrographic, and oxygen measurements at the mooring show the impact of eddies on the weak flow region of the eastern tropical South Pacific. Strong anomalies are related to the passage of eddies and are not associated with a seasonal signal in the open ocean. The mass transport of the four observed eddies across 85°W is between 1.1 and 1.8Sv. The eddy type-dependent available heat, salt, and oxygen anomalies are 8.1×1018J (ACE2), 1.0×1018J (MWE), and −8.9×1018J (CE) for heat; 25.2×1010kg (ACE2), −3.1×1010kg (MWE), and −41.5×1010kg (CE) for salt; and −3.6×1016µmol (ACE2), −3.5×1016µmol (MWE), and −6.5×1016µmol (CE) for oxygen showing a strong imbalance between anticyclones and cyclones for salt transports probably due to seasonal variability in water mass properties in the formation region of the eddies. Heat, salt, and oxygen fluxes out of the coastal region across the ORS region in the oligotrophic open South Pacific are estimated based on these eddy anomalies and on eddy statistics (gained out of 23 years of satellite data). Furthermore, four profiling floats were trapped in the ACE2 during its westward propagation between the formation region and the open ocean, which allows for conclusions on lateral mixing of water mass properties with time between the core of the eddy and the surrounding water. The strongest lateral mixing was found between the seasonal thermocline and the eddy core during the first half of the eddy lifetime

Transformational Leadership, High-Performance Work System Consensus, and Customer Satisfaction

We use human resources (HR) system strength theory to argue that transformational leadership leads to employee consensus on a unit’s high-performance work system (HPWS), that consensus helps align employee attitudes, and that a compression in attitudes facilitates strategy execution and unit-level outcomes. Empirical tests based on a 4-year linked employee–customer panel data set, involving 255 do-it-yourself stores, support our predictions. Transformational leadership is positively related to HPWS consensus. Consensus is negatively associated with unit-level job satisfaction dispersion, which in turn relates positively to unit-level customer satisfaction. Our study makes important contributions to the strategic HR and HR system strength literatures, highlighting the roles of leadership and employee consensus in strategy execution

"Kundenzufriedenheit" bei ambulanten Pflegedienstleistern: Bestandsaufnahme und Vorschläge für ein stresstheoretisch fundiertes Messinstrument

Der Artikel gibt einen Überblick zum Stand der Forschung zur Qualitätssicherung in der ambulanten Pflege. Es werden Erfahrungen und Instrumente zur Messung von Patientenzufriedenheit referiert. Die unzureichende theoretische Fundierung der meisten Messinstrumente wird als Manko herausgestellt. Aufbauend auf stresstheoretischen Überlegungen werden Vorschläge zur Fundierung eines neuen Instrumentes unterbreitet. Grundlage ist das transaktionale Modell von Lazarus und Launier. Zusätzlich werden theoretische Überlegungen zu den Facetten des Konstruktes entwickelt. Es folgen Beispiele zur Operationalisierung. Ein Fazit sowie ein Ausblick auf geplante Vorhaben bilden den Schluss des Artikels.This report deals with quality assurance in ambulant care. Experiences are discussed and instruments for the measurement of patient satisfaction are presented. Most of the instruments lack a theoretical basis. Therefore stress theories are suggested as theoretical background for the measurement of the construct. The further argumentation is based on a transactional perspective. Additionally facets and components of the construct are developed. The report finishes with examples for the operationalization, a final conclusion and an outlook an future plans

Extended stereotactic brain biopsy in suspected primary central nervous system angiitis: good diagnostic accuracy and high safety

OBJECTIVE To evaluate the diagnostic accuracy and safety of extended stereotactic brain biopsy (ESBB) in a single center cohort with suspected primary angiitis of the central nervous system (PACNS). METHODS A standardized stereotactic biopsy targeting MRI-positive lesions and collecting samples from the meninges and the cortex as well as from the white matter was performed in 23 patients with clinically suspected PACNS between 2010 and 2017. The relationship between biopsy yield and clinical characteristics, cerebrospinal fluid parameters, MR-imaging, time point of biopsy and exact localization of biopsy as well as number of tissue samples were examined. RESULTS PACNS was confirmed in 7 of 23 patients (30.4%). Alternative diagnoses were identified in 7 patients (30%). A shorter time period between the onset or worsening of symptoms (p = 0.018) and ESBB significantly increased the diagnostic yield. We observed only minor and transient postoperative complications in 3 patients (13.0%). ESBB led to a direct change of the therapeutic regime in 13 of 23 patients (56.5%). Careful neuropathological analysis furthermore revealed that cortical samples were crucial in obtaining a diagnosis. CONCLUSION ESBB is a safe approach with good feasibility, even in critically ill patients, and high diagnostic accuracy in patients with suspected PACNS changing future therapies in 13 of 23 patients (56.5%). Early biopsy after symptom onset/worsening is crucial and (sub)acute MRI-lesions should be targeted with a particular need for biopsy samples from the cortical layer

Observation of enhanced chiral asymmetries in the inner-shell photoionization of uniaxially oriented methyloxirane enantiomers

Most large molecules are chiral in their structure: they exist as two enantiomers, which are mirror images of each other. Whereas the rovibronic sublevels of two enantiomers are almost identical, it turns out that the photoelectric effect is sensitive to the absolute configuration of the ionized enantiomer - an effect termed Photoelectron Circular Dichroism (PECD). Our comprehensive study demonstrates that the origin of PECD can be found in the molecular frame electron emission pattern connecting PECD to other fundamental photophysical effects as the circular dichroism in angular distributions (CDAD). Accordingly, orienting a chiral molecule in space enhances the PECD by a factor of about 10

A combined measurement of cosmic growth and expansion from clusters of galaxies, the CMB and galaxy clustering

Combining galaxy cluster data from the ROSAT All-Sky Survey and the Chandra X-ray Observatory, cosmic microwave background data from the Wilkinson Microwave Anisotropy Probe, and galaxy clustering data from the WiggleZ Dark Energy Survey, the 6-degree Field Galaxy Survey and the Sloan Digital Sky Survey III, we test for consistency the cosmic growth of structure predicted by General Relativity (GR) and the cosmic expansion history predicted by the cosmological constant plus cold dark matter paradigm (LCDM). The combination of these three independent, well studied measurements of the evolution of the mean energy density and its fluctuations is able to break strong degeneracies between model parameters. We model the key properties of cosmic growth with the normalization of the matter power spectrum, sigma_8, and the cosmic growth index, gamma, and those of cosmic expansion with the mean matter density, Omega_m, the Hubble constant, H_0, and a kinematical parameter equivalent to that for the dark energy equation of state, w. For a spatially flat geometry, w=-1, and allowing for systematic uncertainties, we obtain sigma_8=0.785+-0.019 and gamma=0.570+0.064-0.063 (at the 68.3 per cent confidence level). Allowing both w and gamma to vary we find w=-0.950+0.069-0.070 and gamma=0.533+-0.080. To further tighten the constraints on the expansion parameters, we also include supernova, Cepheid variable and baryon acoustic oscillation data. For w=-1, we have gamma=0.616+-0.061. For our most general model with a free w, we measure Omega_m=0.278+0.012-0.011, H_0=70.0+-1.3 km s^-1 Mpc^-1 and w=-0.987+0.054-0.053 for the expansion parameters, and sigma_8=0.789+-0.019 and gamma=0.604+-0.078 for the growth parameters. These results are in excellent agreement with GR+LCDM (gamma~0.55; w=-1) and represent the tightest and most robust simultaneous constraint on cosmic growth and expansion to date.Comment: 14 pages, 5 figures, 1 table. Matches the accepted version for MNRAS. New sections 3 and 6 added, containing 2 new figures. Table extended. The results including BAO data have been slightly modified due to an updated BAO analysis. Conclusions unchange

Bayesian inference reveals positive but subtle effects of experimental fishery closures on marine predator demographics

Global forage-fish landings are increasing, with potentially grave consequences for marine ecosystems. Predators of forage fish may be influenced by this harvest, but the nature of these effects is contentious. Experimental fishery manipulations offer the best solution to quantify population-level impacts, but are rare. We used Bayesian inference to examine changes in chick survival, body condition and population growth rate of endangered African penguins Spheniscus demersus in response to 8 years of alternating time-area closures around two pairs of colonies. Our results demonstrate that fishing closures improved chick survival and condition, after controlling for changing prey availability. However, this effect was inconsistent across sites and years, highlighting the difficultly of assessing management interventions in marine ecosystems. Nevertheless, modelled increases in population growth rates exceeded 1% at one colony; i.e. the threshold considered biologically meaningful by fisheries management in South Africa. Fishing closures evidently can improve the population trend of a forage-fish-dependent predator-we therefore recommend they continue in South Africa and support their application elsewhere. However, detecting demographic gains for mobile marine predators from small no-take zones requires experimental time frames and scales that will often exceed those desired by decision makers

Revealing the two-electron cusp in the ground states of He and H2 via quasifree double photoionization

We report on kinematically complete measurements and ab initio nonperturbative calculations of double ionization of He and H 2 by a single 800 eV circularly polarized photon. We confirm the quasifree mechanism of photoionization for H 2 and show how it originates from the two-electron cusp in the ground state of a two-electron target. Our approach establishes a method for mapping electrons relative to each other and provides valuable insight into photoionization beyond the electric-dipole approximation.We acknowledge support by DFG and BMBF