2,154 research outputs found
Clover rot (Sclerotinia trifolium) and Fusarium fungi in organic red clover in Finland
Sclerotinia trifolium is economically one of the most important pathogens of red clover in Europe and North America, while many Fusarium species can cause root rot in red clover in certain environmental conditions. During the years 2003-2004 S. trifolium was found only in the Northern and Eastern part of Finland, although in 1960's it was common everywhere in Finland
Higher-dimensional multifractal value sets for conformal infinite graph directed Markov systems
We give a description of the level sets in the higher dimensional
multifractal formalism for infinite conformal graph directed Markov systems. If
these systems possess a certain degree of regularity this description is
complete in the sense that we identify all values with non-empty level sets and
determine their Hausdorff dimension. This result is also partially new for the
finite alphabet case.Comment: 20 pages, 1 figur
ALMA detection of the dusty object silhouetted against the S0 galaxy NGC 3269 in the Antlia cluster
Context. An intriguing silhouette of a small dust patch can be seen against the disk of the S0 galaxy NGC 3269 in the Antlia cluster in optical images. The images do not provide any clue as to whether the patch is a local Jupiter mass-scale cloudlet or a large extragalactic dust complex.Aims. We aim to resolve the nature of this object: is it a small Galactic cloudlet or an extragalactic dust complex?Methods. ALMA and APEX spectroscopy and Gemini GMOS long-slit spectroscopy were used to measure the velocity of the patch and the NGC 3269 disk radial velocity curve.Results. A weak 16 2.5 km s(-1) wide (CO)-C-12(2-1) T-MB 19 +/- 2.5. mK line in a 2 .('') . '' 2 by 2 .('') .'' 12 beam associated with the object was detected with ALMA. The observed heliocentric velocity, V-r,V- hel=3878 +/- 5.0 km s(-1), immediately establishes the extragalactic nature of the object. The patch velocity is consistent with the velocity of the nucleus of NGC 3269, but not with the radial velocity of the NGC 3269 disk of the galaxy at its position. The similar to 4 '' angular size of the patch corresponds to a linear size of similar to 1 kpc at the galaxy's Hubble distance of 50.7 Mpc. The mass estimated from the (CO)-C-12(2-1) emission is similar to 1.4x10(6)(d/50.7 Mpc)M-2(circle dot), while the attenuation derived from the optical spectrum implies a dust mass of similar to 2.6x10(4)(d/50.7 Mpc)M-2(circle dot). The derived attenuation ratio A ' (B)/(A ' (B)-A ' (R)) of 1.6 +/- 0.11 is substantially lower than the corresponding value for the mean Milky Way extinction curve for point sources (2.3).Conclusions. We established the extragalactic nature of the patch, but its origin remains elusive. One possibility is that the dust patch is left over from the removal of interstellar matter in NGC 3269 through the interaction with its neighbour, NGC 3268.Peer reviewe
Properties of dust in the high-latitude translucent cloud L1780 I: Spatially distinct dust populations and increased dust emissivity from ISO observations
We have analyzed the properties of dust in the high galactic latitude
translucent cloud Lynds 1780 using ISOPHOT maps at 100 and 200 micrometers and
raster scans at 60, 80, 100, 120, 150 and 200 micrometers. In far-infrared
(FIR) emission, the cloud has a single core that coincides with the maxima of
visual extinction and 200um optical depth. At the resolution of 3.0 arcmin, the
maximum visual extinction is 4.0 mag. At the cloud core, the minimum
temperature and the maximum 200um optical depth are 14.9+/-0.4 K and
2.0+/-0.2x10^{-3}, respectively, at the resolution of 1.5 arcmin. The cloud
mass is estimated to be 18M_{SUN}. The FIR observations, combined with IRAS
observations, suggest the presence of different, spatially distinct dust grain
populations in the cloud: the FIR core region is the realm of the "classical"
large grains, whereas the very small grains and the PAHs have separate maxima
on the Eastern side of the cold core, towards the "tail" of this
cometary-shaped cloud. The color ratios indicate an overabundance of PAHs and
VSGs in L1780. Our FIR observations combined with the optical extinction data
indicate an increase of the emissivity of the big grain dust component in the
cold core, suggesting grain coagulation or some other change in the properties
of the large grains. Based on our observations, we also address the question,
to what extent the 80um emission and even the 100um and the 120um emission
contain a contribution from the small-grain component.Comment: 12 pages, 9 figures, minor changes, one table adde
Unidentified Infrared Emission Bands in the Diffuse Interstellar Medium
Using the Mid-Infrared Spectrometer on board the Infrared Telescope in Space
and the low-resolution grating spectrometer (PHT-S) on board the Infrared Space
Observatory, we obtained 820 mid-infrared (5 to 12 m) spectra of the
diffuse interstellar medium (DIM) in the Galactic center, W51, and Carina
Nebula regions. These spectra indicate that the emission is dominated by the
unidentified infrared (UIR) emission bands at 6.2, 7.7, 8.6, and 11.2 m.
The relative band intensities (6.2/7.7 m, 8.6/7.7 m, and 11.2/7.7
m) were derived from these spectra, and no systematic variation in these
ratios was found in our observed regions, in spite of the fact that the
incident radiation intensity differs by a factor of 1500. Comparing our results
with the polycyclic aromatic hydrocarbons (PAHs) model for the UIR band
carriers, PAHs in the DIM have no systematic variation in their size
distribution, their degree of dehydrogenation is independent of the strength of
UV radiation field, and they are mostly ionized. The latter finding is
incompatible with past theoretical studies, in which a large fraction of
neutral PAHs is predicted in this kind of environment. A plausible resolution
of this discrepancy is that the recombination coefficients for electron and
large PAH positive ion are by at least an order of magnitude less than those
adopted in past theoretical studies. Because of the very low population of
neutral state molecules, photoelectric emission from interstellar PAHs is
probably not the dominant source of heating of the diffuse interstellar gas.
The present results imply constant physical and chemical properties of the
carriers of the UIR emission bands in the DIM.Comment: 13 pages, 6 figures. Accepted for publication in Ap
Far infrared observations of pre-protostellar sources in Lynds 183
Using ISOPHOT maps at 100 and 200um and raster scans at 100, 120, 150 and
200um we have detected four unresolved far-infrared sources in the high
latitude molecular cloud L183. Two of the sources are identified with 1.3mm
continuum sources found by Ward-Thompson et al. and are located near the
temperature minimum and the coincident column density maximum of dust
distribution. For these two sources, the ISO observations have enabled us to
derive temperatures (about 8.3 K) and masses (about 1.4 and 2.4 solar masses).
They are found to have masses greater than or comparable to their virial masses
and are thus expected to undergo gravitational collapse. We classify them as
pre-protostellar sources. The two new sources are good candidates for
pre-protostellar sources or protostars within L183.Comment: 12 pages, 7 Postscript figures, 1 JPEG figure. Accepted for
publication in Astronomy & Astrophysic
Effect of Donor Simvastatin Treatment on Gene Expression Profiles in Human Cardiac Allografts during Ischemia-Reperfusion Injury
Purpose Numerous studies have shown that statin therapy initiated early after heart transplantation has beneficial effects on the development of cardiac allograft vasculopathy. Recently, we were able to show in a randomized clinical trial that simvastatin treatment of brain-dead donors conditions the heart transplant to withstand ischemia-reperfusion injury and to reduce the need for rejection treatments early after transplantation. In this study, we analyzed myocardial gene expression profiles in cardiac allografts after donor simvastatin treatment. Methods 84 heart transplant donors received 80 mg of simvastatin via nasogastric tube (n=42), or no treatment (n=42) in a prospective, double-blinded randomized controlled trial. Transmural Tru-Cut biopsies were taken from the apex of left ventricle of the donor heart immediately before reperfusion and 1 hour after reperfusion. 20 heart biopsies from donors without treatment and 20 heart biopsies from donors with simvastatin treatment will be analyzed with RNA sequencing. Results The preliminary analysis of RNA sequencing data from myocardial biopsies revealed altogether 137 significantly differentially expressed genes in all pairwise comparisons. The overall biological functions of these genes were related to gene ontology terms such as response to toxic substance, leukocyte migration, neutrophil mediated immunity, response to lipopolysaccharide, and response to oxidative stress. At the KEGG pathway level, our results indicated alterations in IL-17, TNF, MAPK and the AGE-RAGE signaling pathways. Conclusion We have shown in previous studies that donor simvastatin treatment induces protective effects against IRI in heart transplant recipients. In this study, we were able to detect significantly differentially expressed genes related to effects of simvastatin treatment. In order to single out genes that show beneficial effects of simvastatin treatment, further analysis will be conducted by exploring gene expression changes in specific biological functional categories, such as interleukin signaling and neutrophil degranulation. The complete analysis will be presented at the ISHLT 2019 congress.Peer reviewe
Sixty Years of Fractal Projections
Sixty years ago, John Marstrand published a paper which, among other things,
relates the Hausdorff dimension of a plane set to the dimensions of its
orthogonal projections onto lines. For many years, the paper attracted very
little attention. However, over the past 30 years, Marstrand's projection
theorems have become the prototype for many results in fractal geometry with
numerous variants and applications and they continue to motivate leading
research.Comment: Submitted to proceedings of Fractals and Stochastics
Diffuse Galactic Emission from Spinning Dust Grains
Spinning interstellar dust grains produce detectable rotational emission in
the 10-100 GHz frequency range. We calculate the emission spectrum, and show
that this emission can account for the ``anomalous'' Galactic background
component which correlates with 100um thermal emission from dust. Implications
for cosmic background studies are discussed.Comment: 13 pages, 3 eps figures, uses aaspp4.sty . Accepted by Ap.J.Letters
97/12/09. Corrected typos and added 1 referenc
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