Verbesserte Bestimmung des Chloridgehalts in Beton durch neues Messverfahren

Die ASFiNAG unterhält mehr als 5.000 Brückenobjekte im Straßennetz. Die meisten von ihnen wurden in Stahlbeton- oder Spannbetonbauweise errichtet und insbesondere die Stützen sind hohen Belastungen durch Chlorid ausgesetzt. Dies führt langfristig zu einer Verringerung der Dauerhaftigkeit und Instandsetzungen sind daher erforderlich. Eine genaue Ermittlung der Depassivierung und ein Prognosemodell sind bei Chloridbelastung besonders wichtig für eine kosteneffiziente Erhaltung. Die neue Methode LA-ICP-MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometry) ermöglicht exaktere Ergebnisse als die traditionelle Chloridbestimmung mittels Titration. Die Vorteile der beiden Methoden werden im Beitrag diskutiert und die Ergebnisse verglichen. Es wird gezeigt, dass die LA-ICP-MS-Methode zuverlässigere Ergebnisse liefert und durch die hohe Ortsauflösung der Chloridprofile sowie die genaue Bestimmung des Chloridgehalts noch nicht dagewesene Möglichkeiten für eine exakte Beurteilung und Prognose eröffnet

Effect of a 25 ingredient sport drink on exercise performance and muscle oxygen extraction: a randomized controlled cross-over trial

Many sport drinks contain a mixture of potential ergogenic substances. Recently, a new sport drink with 25 different ingredients was introduced to the market. Various athletes reported beneficial performance effects from the supplement, though without scientific evidence. The aim of this study was to investigate the effects of the sport drink on exercise performance. Nine sport students performed 3 test sessions including a cycle exercise tests to exhaustion, a leg strength test and a jump test. Each session was separated by 1 week. The first session was performed as a familiarization trial. In a random order, half of the participants performed the second session after consumption of the multi ingredient sport drink (MISD intake of 40g, 24 and 1h before each test) and half after placebo ingestion (same amount). During test session 3 the conditions were reversed (cross-over setting). Near infrared spectroscopy analyses were performed on the vastus lateralis during the MISD and placebo cycling test. The sport drink compared to placebo, improved maximal power output (7 watts, 95% CI 1.1-13.4), increased maximal lactate concentration (2.5 mmol/l, 95% CI 1.6-3.4), and power output at the individual threshold (Dmax) (6.1 watts, 95% CI 1.9-10.3). Power output at the 4 mmol/l threshold was reduced (9.0 watts, 95% CI -17.4 to -0.6) during the MISD trial. Additionally, the sport drink led to a steeper tissue oxygenation index decrease (TOI, slope: -0.0182±0.0084 vs. -0.0256±0.0073, p<0.005) during the test. Leg strength and jump ability was not affected by the supplement. The sport drink slightly increased power output during an incremental exercise test. Due to the broad range of substances in the supplement and their different effects, the factors involved in the performance enhancement are speculative. Data show that factors other than muscle oxygen extraction (represented by TOI) are involved in the improved maximal power output

Coordination and communication in healthcare action teams

Communication and coordination represent central processes in healthcare action teams. However, we have a limited understanding of how expertise affects these processes and to what extent these effects are shaped by interprofessional differences. The current study addresses these questions by jointly investigating the influence of different aspects of expertise – individual expertise, team familiarity, and expertise asymmetry – on coordination quality and communication openness. We tested our propositions in two hospitals: one in Switzerland (CH, Sample 1) and one in the United Kingdom (UK, Sample 2). Both samples included two-person anesthesia action teams consisting of a physician and a nurse (N/CH = 47 teams, N/UK = 48 teams). We used a correlational design with two measurement points (i.e., pre- and postoperation). To consider potential interprofessional differences, we analyzed our data with actor-partner interdependence models. Moreover, we explored differences in the effects of expertise between both hospitals. Our findings suggest that nurses’ expertise is the most important predictor of coordination quality and communication openness. Overall, differences between the two hospitals were more prevalent than interprofessional differences between physicians and nurses. The current study provides a nuanced picture of the effects of expertise, and thereby extends our understanding of interprofessional teamwork

The GRAVITY instrument software / High-level software

GRAVITY is the four-beam, near- infrared, AO-assisted, fringe tracking, astrometric and imaging instrument for the Very Large Telescope Interferometer (VLTI). It is requiring the development of one of the most complex instrument software systems ever built for an ESO instrument. Apart from its many interfaces and interdependencies, one of the most challenging aspects is the overall performance and stability of this complex system. The three infrared detectors and the fast reflective memory network (RMN) recorder contribute a total data rate of up to 20 MiB/s accumulating to a maximum of 250 GiB of data per night. The detectors, the two instrument Local Control Units (LCUs) as well as the five LCUs running applications under TAC (Tools for Advanced Control) architecture, are interconnected with fast Ethernet, RMN fibers and dedicated fiber connections as well as signals for the time synchronization. Here we give a simplified overview of all subsystems of GRAVITY and their interfaces and discuss two examples of high-level applications during observations: the acquisition procedure and the gathering and merging of data to the final FITS file.Comment: 8 pages, 7 figures, published in Proc. SPIE 9146, Optical and Infrared Interferometry IV, 91462

Fluorosolvatochromism of furanyl- and thiophenyl-substituted acetophenones

A series of para-substituted acetophenones bearing a furanyl or a thiophenyl moiety show a large Stokes-shift, which is a function of various solvent properties. Photophysical properties such as emission lifetime of the compounds have been determined using time-correlated-single photon counting to secure the intrinsic fluorescence behaviour. The solvent dependent position of the UV/Vis emission band [small nu, Greek, tilde]max,em of the compounds has been measured in 26 various solvents. The influence of the solvent on [small nu, Greek, tilde]max,em is of very complex nature and mathematically analysed by multiple square linear solvation energy (LSE)-correlation analysis using Catalán's four-solvent parameter set. Solvent acidity has a strong influence on the bathochromic shift of 2,5-disubstituted furan derivatives compared to the non-5-substituted furan and thiophene derivatives, which show a contrary behaviour. Therefore, the 5-cyanofuranyl-substituted acetophenone derivative is useful as a probe for measuring environmental properties by fluorescence spectroscopy.Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

Adaptive fast multipole methods on the GPU

We present a highly general implementation of fast multipole methods on graphics processing units (GPUs). Our two-dimensional double precision code features an asymmetric type of adaptive space discretization leading to a particularly elegant and flexible implementation. All steps of the multipole algorithm are efficiently performed on the GPU, including the initial phase which assembles the topological information of the input data. Through careful timing experiments we investigate the effects of the various peculiarities of the GPU architecture.Comment: Software available at http://user.it.uu.se/~stefane/freeware.htm

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Evaluation of the Use of PCR and Reverse Transcriptase PCR for Detection of Pathogenic Bacteria in Biosolids from Anaerobic Digestors and Aerobic Composters

A PCR-based method and a reverse transcriptase PCR (RT-PCR)-based method were developed for the detection of pathogenic bacteria in organic waste, using Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica, and Staphylococcus aureus as model organisms. In seeded organic waste samples, detection limits of less than 10 cells per g of organic waste were achieved after one-step enrichment of bacteria, isolation, and purification of DNA or RNA before PCR or RT-PCR amplification. To test the reproducibility and reliability of the newly developed methods, 46 unseeded samples were collected from diverse aerobic (composting) facilities and anaerobic digestors and analyzed by both culture-based classical and newly developed PCR-based procedures. No false-positive but some false-negative results were generated by the PCR- or RT-PCR-based methods after one-step enrichment when compared to the classical detection methods. The results indicated that the level of activity of the tested bacteria in unseeded samples was very low compared to that of freshly inoculated cells, preventing samples from reaching the cell density required for PCR-based detection after one-step enrichment. However, for Salmonella spp., a distinct PCR product could be obtained for all 22 nonamended samples that tested positive for Salmonella spp. by the classical detection procedure when a selective two-step enrichment (20 h in peptone water at 37°C and 24 h in Rappaport Vassiliadis medium at 43°C) was performed prior to nucleic acid extraction and PCR. Hence, the classical procedure was shortened, since cell plating and further differentiation of isolated colonies can be omitted, substituted for by highly sensitive and reliable detection based on nucleic acid extraction and PCR. Similarly, 2 of the 22 samples in which Salmonella spp. were detected also tested positive for Listeria monocytogenes according to a two-step enrichment procedure followed by PCR, compared to 3 samples that tested positive when classical isolation procedures were followed. The study shows that selective two-step enrichment is useful when very low numbers of bacterial pathogens must be detected in organic waste materials, such as biosolids. There were no false-positive results derived from DNA of dead cells in the waste sample, suggesting that it is not necessary to perform RT-PCR analyses when PCR is combined with selective enrichment. Large numbers of added nontarget bacteria did not affect detection of Salmonella spp., L. monocytogenes, and Y. enterocolitica but increased the detection limit of Staphylococcus aureus from <10 to 10(4) CFU/g of organic waste. Overall, the detection methods developed using seeded organic waste samples from one waste treatment facility (WTF) needed to be modified for satisfactory detection of pathogens in samples from other WTFs, emphasizing the need for extensive field testing of laboratory-derived PCR protocols. A survey of 13 WTFs in Germany revealed that all facilities complied with the German Biowaste Ordinance, which mandates that the end product after anaerobic digestion or aerobic composting be free of Salmonella. In addition, all biosolids were free of L. monocytogenes, Staphylococcus aureus, and Y. enterocolitica, as evidenced by both classical and PCR-based detection methods

Verbesserte Bestimmung des Chloridgehalts in Beton durch neues Messverfahren

Die ASFiNAG unterhält mehr als 5.000 Brückenobjekte im Straßennetz. Die meisten von ihnen wurden in Stahlbeton- oder Spannbetonbauweise errichtet und insbesondere die Stützen sind hohen Belastungen durch Chlorid ausgesetzt. Dies führt langfristig zu einer Verringerung der Dauerhaftigkeit und Instandsetzungen sind daher erforderlich. Eine genaue Ermittlung der Depassivierung und ein Prognosemodell sind bei Chloridbelastung besonders wichtig für eine kosteneffiziente Erhaltung. Die neue Methode LA-ICP-MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometry) ermöglicht exaktere Ergebnisse als die traditionelle Chloridbestimmung mittels Titration. Die Vorteile der beiden Methoden werden im Beitrag diskutiert und die Ergebnisse verglichen. Es wird gezeigt, dass die LA-ICP-MS-Methode zuverlässigere Ergebnisse liefert und durch die hohe Ortsauflösung der Chloridprofile sowie die genaue Bestimmung des Chloridgehalts noch nicht dagewesene Möglichkeiten für eine exakte Beurteilung und Prognose eröffnet