Acinetobacter baumannii from Samples of Commercially Reared Turkeys: Genomic Relationships, Antimicrobial and Biocide Susceptibility

Acinetobacter baumannii is especially known as a cause of nosocomial infections worldwide. It shows intrinsic and acquired resistances to numerous antimicrobial agents, which can render the treatment difficult. In contrast to the situation in human medicine, there are only few studies focusing on A. baumannii among livestock. In this study, we have examined 643 samples from turkeys reared for meat production, including 250 environmental and 393 diagnostic samples, for the presence of A. baumannii. In total, 99 isolates were identified, confirmed to species level via MALDI-TOF-MS and characterised with pulsed-field gel electrophoresis. Antimicrobial and biocide susceptibility was tested by broth microdilution methods. Based on the results, 26 representative isolates were selected and subjected to whole-genome sequencing (WGS). In general, A. baumannii was detected at a very low prevalence, except for a high prevalence of 79.7% in chick-box-papers (n = 118) of one-day-old turkey chicks. The distributions of the minimal inhibitory concentration values were unimodal for the four biocides and for most of the antimicrobial agents tested. WGS revealed 16 Pasteur and 18 Oxford sequence types, including new ones. Core genome MLST highlighted the diversity of most isolates. In conclusion, the isolates detected were highly diverse and still susceptible to many antimicrobial agents

Mediterranean swordfish (Xiphias gladius Linnaeus, 1758) population structure revealed by microsatellite DNA: genetic diversity masked by population mixing in shared areas

Background The Mediterranean swordfish stock is overfished and considered not correctly managed. Elucidating the patterns of the Mediterranean swordfish population structure constitutes an essential prerequisite for effective management of this fishery resource. To date, few studies have investigated intra-Mediterranean swordfish population structure, and their conclusions are controversial. Methods A panel of 20 microsatellites DNA was used to investigate fine-scale population structuring of swordfish from six main fishing areas of the Mediterranean Sea. Results This study provides evidence to reject the hypothesis of a single swordfish population within the Mediterranean Sea. DAPC analysis revealed the presence of three genetic clusters and a high level of admixture within the Mediterranean Sea. Genetic structure was supported by significant FST values while mixing was endorsed by the heterozygosity deficit observed in sampling localities indicative of a possible Wahlund effect, by sampling admixture individuals. Overall, our tests reject the hypothesis of a single swordfish population within the Mediterranean Sea. Homing towards the Mediterranean breeding areas may have generated a weak degree of genetic differentiation between populations even at the intra-basin scale

Highly Structured Wind in Vela X-1

We present an in-depth analysis of the spectral and temporal behavior of a long almost uninterrupted INTEGRAL observation of Vela X-1 in Nov/Dec 2003. In addition to an already high activity level, Vela X-1 exhibited several very intense flares with a maximum intensity of more than 5 Crab in the 20 40 keV band. Furthermore Vela X-1 exhibited several off states where the source became undetectable with ISGRI. We interpret flares and off states as being due to the strongly structured wind of the optical companion: when Vela X-1 encounters a cavity in the wind with strongly reduced density, the flux will drop, thus potentially triggering the onset of the propeller effect which inhibits further accretion, thus giving rise to the off states. The required drop in density to trigger the propeller effect in Vela X-1 is of the same order as predicted by theoretical papers for the densities in the OB star winds. The same structured wind can give rise to the giant flares when Vela X-1 encounters a dense blob in the wind. Further temporal analysis revealed that a short lived QPO with a period of 6800 sec is present. The part of the light curve during which the QPO is present is very close to the off states and just following a high intensity state, thus showing that all these phenomena are related

High variability in Vela X-1: giant flares and off states

We investigate the spectral and temporal behavior of the high mass X-ray binary Vela X-1 during a phase of high activity, with special focus on the observed giant flares and off states. INTEGRAL observed Vela X-1 in a long almost uninterrupted observation for two weeks in 2003 Nov/Dec. The data were analyzed with OSA 7.0 and FTOOLS 6.2. We derive the pulse period, light curves, spectra, hardness ratios, and hardness intensity diagrams, and study the eclipse. In addition to an already high activity level, Vela X-1 exhibited several intense flares, the brightest ones reaching a maximum intensity of more than 5 Crab in the 20-40 keV band and several off states where the source was no longer detected by INTEGRAL. We determine the pulse period to be 283.5320+/-0.0002 s, which is stable throughout the entire observation. Analyzing the eclipses provided an improvement in the ephemeris. Spectral analysis of the flares indicates that there appear to be two types of flares: relatively brief flares, which can be extremely intense and show spectral softening, in contrast to high intensity states, which are longer and show no softening. Both flares and off states are interpreted as being due to a strongly structured wind of the optical companion. When Vela X-1 encounters a cavity with strongly reduced density, the flux will drop triggering the onset of the propeller effect, which inhibits further accretion, giving rise to off states. The sudden decrease in the density of the material required to trigger the propeller effect in Vela X-1 is of the same order as predicted by theoretical papers about the densities in OB star winds. A similarly structured wind can produce giant flares when Vela X-1 encounters a dense blob in the wind.Comment: 15 pages, 11 figures, accepted for publication in Astronomy and Astrophysics as of August 2, 200

Concentrating Solar Power at higher limits: Studies on molten Nitrate Salts at 620°C in a laboratory pilot-scale hot tank

Zielsetzung des Laufenden Projektes ist es die Stabilisierung von Nitratsalz bis Temperaturen von 620 °C und Scale-Up Effekte zu untersuchen. Ein wesentlicher Aspekt ist dabei die Stabilisierung mittels Konservierung der entstehenden reaktiven Gase im System. In dieser Arbeit wurden die Erkenntnisse aus den Laborversuchen auf den 100 kg Maßstab übertragen. Das System wurde in einem semi-geschlossenen Zustand mit einem maximalen Überdruck von 20 mbar gefahren und parallel die Gaszusammensetzung sowie die Salzzusammensetzung gemessen und untersucht

Synthetic biofuels by molten salt-catalytic conversion - Corrosion of structural materials in ternary molten chlorides

The molten-salt catalytic conversion of biomass into synthetic fuels is one of the promising renewable energy topics of the 21st century. Mixtures of Zn-Na-K//Cl have gained attention, acting as catalytically active heat transfer fluids in the conversion process, due to their low costs and principally low melting points which effectively lower the required operating temperature in the catalytic reactor. Herein, the corrosion behavior of three candidate steels, SS316L, SS321, and Alloy 800, in the pure molten salt, in a salt-biomass mix, and in a salt-biomass mix containing a corrosion inhibitor (zinc oxide (ZnO)) is comprehensively investigated. The herein described study demonstrates that biomass additions increase the penetration depth of the salt, and the corrosion mechanism leads to partial spalling of the oxide scale. This is attributed to the presence of oxygen and moisture from the biomass leading to the formation of reactive HCl gas. The addition of ZnO reduced the corrosivity of the molten salt-biomass mix, and all alloys obtained a protective, adherent, and thin oxide scale leading to the conclusion that ZnO indeed is an effective corrosion inhibitor for the presented salt system. These findings constitute a major advance in the implementation of molten salt-catalytic reactors for renewable synthetic fuel production

Status on molten nitrate salts above 600 °C

Molten nitrate salts are state-of-the-art heat transfer fluids (HTF) and thermal energy storage (TES) in Concentrating Solar Power (CSP) plants. Only recently, the authors of this work demonstrated that higher operating temperatures of at least 620°C can be realized, compared to state-of-the-art temperatures of 565 °C. The development principally enables the transformation of conventional power plants (e.g. coal) into Storage Power Plants that can absorb peak currents from fluctuating renewable sources. The presentation outlines the potential of nitrate salts in these new fields of application with a particular view on the material research level. In the last years the scientific community has made important progress in understanding the fundamental reaction mechanisms in nitrate salts at temperatures above 600 °C. Yet, the schematic description is far from complete and in the presentation we will outline the recent progress and timeline required for the successful implementation of Molten Salt storage above 600 °C

Emergence of porcine epidemic diarrhea virus in southern Germany

Background Over the last years, porcine epidemic diarrhea virus (PEDV) has caused devastating enteric diseases in the US and several countries in Asia, while outbreaks in Europe have only been reported sporadically since the 1980s. At present, only insufficient information is available on currently circulating PEDV strains in Europe and their impact on the European swine industry. In this case report, we present epidemic outbreaks of porcine epidemic diarrhea in three farms in South-Western Germany. Case presentation Epidemic outbreaks of diarrhea affecting pigs of all age groups were reported in three farms, one fattening farm and two piglet producing farms, in South-Western Germany between May and November 2014. In the fattening farm yellowish, watery diarrhea without evidence of mucus or blood was associated with a massive reduction of feed consumption. Severity of clinical signs and mortality in young suckling pigs varied significantly between the two affected sow farms. While mortality in suckling piglets reached almost 70 % in one sow herd, no increase in suckling piglet mortality was observed in the second sow farm. In all three cases, PEDV was confirmed in feces and small intestines by RT-qPCR. Phylogenetic analyses based on full-length PEDV genomes revealed high identity among strains from all three herds. Moreover, the German strains showed very high nucleotide identity (99.4 %) with a variant of PEDV (OH851) that was isolated in the United States in January 2014. This strain with insertions and deletions in the S-gene (so called INDEL strains) was reported to show lower virulence. Slightly lower identities were found with other strains from the US and Asia. Conclusion Phylogenetic information on the distribution of PEDV strains in Europe is severely lacking. In this case report we demonstrate that acute outbreaks of PEDV occurred in southern Germany in 2014. Current strains were clearly different from isolates found in the 1980s and were closely related to a PEDV variant found in the US in 2014. Moreover, the present case report indicates that variant strains of PEDV, containing insertions and deletions in the S gene, which were reported to be of lower virulence, might be able to cause high mortality in suckling piglets