792 research outputs found
Untersuchungen zum Vorkommen von Leptospiren-, Toxoplasmen- und PRRSV-Antikörpern sowie von Salmonellen und Spulwurmeiern auf österreichischen Bioschweinebetrieben
In Austria, 80.000 organic fattening pigs are raised on 13% out of all pig production farms. Consumer expectations regarding animal health and welfare and meat quality
are particularly high for organic products (Baumgartner et al. 2003). Health problems in organic pig farming are often related to the outdoor area, exposing the animals to
bacterial and parasitic agents. In this study, data about zoonotic agents as, Leptospira ssp., Toxoplasma gondii and Salmonella were collected. Infections by the Porcine
Reproductive and Respiratory Syndrome Virus (PRRSV) and Ascaris (A.) suum were also investigated. The study included 59 organic farms in Austria. Blood samples and
one faecal group sample from pigs of each farm were taken at the slaughterhouse. Leptospira antibodies were found in all investigated herds. The most frequent serovars were Bratislava with 29%, Icterohämorraghiae with 21% and Canicola with 5%. In 29 herds antibodies against T. gondii were detected at least in one pig. The seroprevalence of PRRSV was 46% of the farms. Only one farm was positive for
Salmonella infantis. In 70% of the faecal samples A. suum eggs were found
Porcine Hepatitis E
Hepatitis E virus (HEV) is a zoonotic agent that can be transmitted from pigs to humans via consumption of pork and products derived of it. Recently, the European Food Safety Authority (EFSA) has published a scientific opinion urging for measures to prevent Hepatitis E virus (HEV) from entering the food chain
SST-GATE: A dual mirror telescope for the Cherenkov Telescope Array
The Cherenkov Telescope Array (CTA) will be the world's first open
observatory for very high energy gamma-rays. Around a hundred telescopes of
different sizes will be used to detect the Cherenkov light that results from
gamma-ray induced air showers in the atmosphere. Amongst them, a large number
of Small Size Telescopes (SST), with a diameter of about 4 m, will assure an
unprecedented coverage of the high energy end of the electromagnetic spectrum
(above ~1TeV to beyond 100 TeV) and will open up a new window on the
non-thermal sky. Several concepts for the SST design are currently being
investigated with the aim of combining a large field of view (~9 degrees) with
a good resolution of the shower images, as well as minimizing costs. These
include a Davies-Cotton configuration with a Geiger-mode avalanche photodiode
(GAPD) based camera, as pioneered by FACT, and a novel and as yet untested
design based on the Schwarzschild-Couder configuration, which uses a secondary
mirror to reduce the plate-scale and to allow for a wide field of view with a
light-weight camera, e.g. using GAPDs or multi-anode photomultipliers. One
objective of the GATE (Gamma-ray Telescope Elements) programme is to build one
of the first Schwarzschild-Couder prototypes and to evaluate its performance.
The construction of the SST-GATE prototype on the campus of the Paris
Observatory in Meudon is under way. We report on the current status of the
project and provide details of the opto-mechanical design of the prototype, the
development of its control software, and simulations of its expected
performance.Comment: In Proceedings of the 33rd International Cosmic Ray Conference
(ICRC2013), Rio de Janeiro (Brazil). All CTA contributions at arXiv:1307.223
Smart Focal Plane Technologies for VLT Instruments
As we move towards the era of ELTs, it is timely to think about the future
role of the 8-m class telescopes. Under the OPTICON programme, novel
technologies have been developed that are intended for use in multi-object and
integral-field spectrographs. To date, these have been targeted at instrument
concepts for the European ELT, but there are also significant possibilities for
their inclusion in new VLT instruments, ensuring the continued success and
productivity of these unique telescopes.Comment: 5 pages, to appear in the proceedings of the ESO Workshop "Science
with the VLT in the ELT era
Relevance of the light signaling machinery for cellulase expression in trichoderma reesei (hypocrea jecorina)
<p>Abstract</p> <p>Background</p> <p>In nature, light is one of the most important environmental cues that fungi perceive and interpret. It is known not only to influence growth and conidiation, but also cellulase gene expression. We therefore studied the relevance of the main components of the light perception machinery of <it>Trichoderma reesei </it>(<it>Hypocrea jecorina</it>), ENV1, BLR1 and BLR2, for production of plant cell wall degrading enzymes in fermentations aimed at efficient biosynthesis of enzyme mixtures for biofuel production.</p> <p>Findings</p> <p>Our results indicate that despite cultivation in mostly dark conditions, all three components show an influence on cellulase expression. While we found the performance of the enzyme mixture secreted by a deletion mutant in <it>env1 </it>to be enhanced, the higher cellulolytic activity observed for <it>Δblr2 </it>is mainly due to an increased secretion capacity of this strain. <it>Δblr1 </it>showed enhanced biomass accumulation, but due to its obviously lower secretion capacity still was the least efficient strain in this study.</p> <p>Conclusions</p> <p>We conclude that with respect to regulation of plant cell wall degrading enzymes, the blue light regulator proteins are unlikely to act as a complex. Their regulatory influence on cellulase biosynthesis involves an alteration of protein secretion, which may be due to adjustment of transcription or posttranscriptional regulation of upstream factors. In contrast, the regulatory function of ENV1 seems to involve adjustment of enzyme proportions to environmental conditions.</p
Diffractive orbits in isospectral billiards
Isospectral domains are non-isometric regions of space for which the spectra
of the Laplace-Beltrami operator coincide. In the two-dimensional Euclidean
space, instances of such domains have been given. It has been proved for these
examples that the length spectrum, that is the set of the lengths of all
periodic trajectories, coincides as well. However there is no one-to-one
correspondence between the diffractive trajectories. It will be shown here how
the diffractive contributions to the Green functions match nevertheless in a
''one-to-three'' correspondence.Comment: 20 pages, 6 figure
3D Spectrophotometry of Planetary Nebulae in the Bulge of M31
We introduce crowded field integral field (3D) spectrophotometry as a useful
technique for the study of resolved stellar populations in nearby galaxies. As
a methodological test, we present a pilot study with selected extragalactic
planetary nebulae (XPN) in the bulge of M31, demonstrating how 3D spectroscopy
is able to improve the limited accuracy of background subtraction which one
would normally obtain with classical slit spectroscopy. It is shown that due to
the absence of slit effects, 3D is a most suitable technique for
spectrophometry. We present spectra and line intensities for 5 XPN in M31,
obtained with the MPFS instrument at the Russian 6m BTA, INTEGRAL at the WHT,
and with PMAS at the Calar Alto 3.5m Telescope. Using 3D spectra of bright
standard stars, we demonstrate that the PSF is sampled with high accuracy,
providing a centroiding precision at the milli-arcsec level. Crowded field 3D
spectrophotometry and the use of PSF fitting techniques is suggested as the
method of choice for a number of similar observational problems, including
luminous stars in nearby galaxies, supernovae, QSO host galaxies,
gravitationally lensed QSOs, and others.Comment: (1) Astrophysikalisches Institut Potsdam, (2) University of Durham.
18 pages, 11 figures, accepted for publication in Ap
Chronic Activation of Hepatic Nrf2 Has No Major Effect on Fatty Acid and Glucose Metabolism in Adult Mice
The transcription factor NF-E2-related factor 2 (Nrf2) induces cytoprotective
genes, but has also been linked to the regulation of hepatic energy
metabolism. In order to assess the pharmacological potential of hepatic Nrf2
activation in metabolic disease, Nrf2 was activated over 7 weeks in mice on
Western diet using two different siRNAs against kelch-like ECH-associated
protein 1 (Keap1), the inhibitory protein of Nrf2. Whole genome expression
analysis followed by pathway analysis demonstrated successful knock-down of
Keap1 expression and induction of Nrf2-dependent genes involved in anti-
oxidative stress defense and biotransformation, proving the activation of Nrf2
by the siRNAs against Keap1. Neither the expression of fatty acid- nor
carbohydrate-handling proteins was regulated by Keap1 knock-down. Metabolic
profiling of the animals did also not show effects on plasma and hepatic
lipids, energy expenditure or glucose tolerance. The data indicate that
hepatic Keap1/Nrf2 is not a major regulator of glucose or lipid metabolism in
mice
An XMM-Newton view of the `bare' nucleus of Fairall 9
We present the spectral results from a 130 ks observation, obtained from the
X-ray Multi-Mirror Mission-Newton (XMM-Newton) observatory, of the type I
Seyfert galaxy Fairall 9. An X-ray hardness-ratio analysis of the light-curves,
reveals a `softer-when-brighter' behaviour which is typical for radio-quiet
type I Seyfert galaxies. Moreover, we analyse the high spectral-resolution data
of the reflection grating spectrometer and we did not find any significant
evidence supporting the presence of warm-absorber in the low X-ray energy part
of the source's spectrum. This means that the central nucleus of Fairall 9 is
`clean' and thus its X-ray spectral properties probe directly the physical
conditions of the central engine. The overall X-ray spectrum in the 0.5-10 keV
energy-range, derived from the EPIC data, can be modelled by a relativistically
blurred disc-reflection model. This spectral model yields for Fairall 9 an
intermediate black-hole best-fit spin parameter of
.Comment: Accepted for publication in MNRAS. The paper contains 11 figures and
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