541 research outputs found
Elimination of mites from the buds of dormant grapevine cuttings by hot water treatment
The suitability of hot water treatment was tested for eliminating overwintering mites from dormant grapevine buds. Treatment at 52 °C for 60 min completely eliminated mite infestation, but did not or only slightly influenced the viability of grapevine buds. In greenhouse experiments we demonstrated that treated plants frequently showed a better growth, most probably due to the elimination of mite infestation. This additional application of hot water treatment provides a simple, environment-friendly and economical method to prevent spreading of grapevine mites
Steroid concentrations in atopic dermatitis patients: Reduced plasma DHEAS and increased cortisone levels.
Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease, which is characterized by a disrupted epidermal barrier function present both in affected skin and in non-affected skin. Mainly glucocorticosteroids were used in topical and systemic atopy treatments because of their potent anti-inflammatory effects, unfortunately with strong side effects. In this study we determined that 2 out of 16 steroids were significantly different in healthy volunteers vs AD-patients. Cortisone, which is higher in AD-patients plasma, is a direct precursor of the bioactive corticosteroid cortisol, which just displays a higher tendency and is known for its potent anti-inflammatory effects. In addition a tendency of reduced levels of the anti-inflammatory ER ligand estrone was found in AD-patients. DHEA is a precursor of testosterone, its levels just display a lower tendency in male AD-patients, while its sulfonation metabolite DHEAS is lower in male and female AD-patients. We found and conclude that altered steroid levels in the plasma of AD-patients indicate altered vitamin D signaling (based on reduced DHEA sulfonation) and increased feedback for anti-inflammatory signaling (increased levels of cortisone) present in AD-patients. This article is protected by copyright. All rights reserved
Identification of Young Stellar Object candidates in the DR2 x AllWISE catalogue with machine learning methods
The second Data Release (DR2) contains astrometric and photometric
data for more than 1.6 billion objects with mean magnitude 20.7,
including many Young Stellar Objects (YSOs) in different evolutionary stages.
In order to explore the YSO population of the Milky Way, we combined the
DR2 database with WISE and Planck measurements and made an all-sky
probabilistic catalogue of YSOs using machine learning techniques, such as
Support Vector Machines, Random Forests, or Neural Networks. Our input
catalogue contains 103 million objects from the DR2xAllWISE cross-match table.
We classified each object into four main classes: YSOs, extragalactic objects,
main-sequence stars and evolved stars. At a 90% probability threshold we
identified 1,129,295 YSO candidates. To demonstrate the quality and potential
of our YSO catalogue, here we present two applications of it. (1) We explore
the 3D structure of the Orion A star forming complex and show that the spatial
distribution of the YSOs classified by our procedure is in agreement with
recent results from the literature. (2) We use our catalogue to classify
published Science Alerts. As measures the sources at multiple
epochs, it can efficiently discover transient events, including sudden
brightness changes of YSOs caused by dynamic processes of their circumstellar
disk. However, in many cases the physical nature of the published alert sources
are not known. A cross-check with our new catalogue shows that about 30% more
of the published alerts can most likely be attributed to YSO activity.
The catalogue can be also useful to identify YSOs among future alerts.Comment: 19 pages, 12 figures, 3 table
(α,n) reaction cross section measurement on 92,94Mo isotopes
The cross section of the 92,94Mo(α,n)95,97Ru reactions were measured recently at MTA Atomki using the activation method and thick targets to study the origin of the proton-rich nuclei heavier than iron. The experimental details of the
cross section measurement are presented in this paper
Experimental determination of the He(,)Be reaction cross section above the Be proton separation threshold
The He(,)Be reaction plays a major role both in the
BBN producing the majority of the primordial Li, and in the pp-chain, where
it is the branching point. As a few-nucleon system, this reaction is often used
to validate ab-initio theoretical calculations and/or test R-matrix theory and
code implementations. For the latter, experimental data in an extended energy
range is of crucial importance to test the fit and extrapolation capabilities
of the different codes. The He(,)Be reaction cross
section has been measured by several groups up to the first resonance
( MeV) in the reaction. However, only one dataset exists
above the Be proton separation threshold measured in a narrow energy range
( MeV). In this work we extend the available experimental
capture cross section database to the energy range of known Be levels. The
activation method was used. The experiment was performed using a thin-window
gas cell with two high-purity Al foils as entrance and exit windows. The
activity of the Be nuclei implanted in the exit/catcher foil was measured
by detecting the yield of the emitted ~rays using shielded high-purity
germanium detectors. New experimental He(,)Be reaction
cross section data were obtained for the first time in the
MeV energy region. The new dataset with about 0.2 MeV step covers the energy
range of known levels and particle separation thresholds. No prominent
structures are observer around the Be levels. The reaction cross section is
slowly increasing with increasing energy. Above the Li threshold, a
decrease starts in the cross section trend. The overall structure of the cross
section suggest a broad resonance peaking around MeV Be
excitation energy, with a width of 8 MeV.Comment: Accepted for publication in PR
Activity of 50 Long-Period Comets Beyond 5.2 AU
Remote investigations of the ancient solar system matter has been
traditionally carried out through the observations of long-period (LP) comets
that are less affected by solar irradiation than the short-period counterparts
orbiting much closer to the Sun. Here we summarize the results of our
decade-long survey of the distant activity of LP comets. We found that the most
important separation in the dataset is based on the dynamical nature of the
objects. Dynamically new comets are characterized by a higher level of activity
on average: the most active new comets in our sample can be characterized by
afrho values >3--4 higher than that of our most active returning comets. New
comets develop more symmetric comae, suggesting a generally isotropic outflow.
Contrary to this, the coma of recurrent comets can be less symmetrical,
ocassionally exhibiting negative slope parameters, suggesting sudden variations
in matter production. The morphological appearance of the observed comets is
rather diverse. A surprisingly large fraction of the comets have long, teniouos
tails, but the presence of impressive tails does not show a clear correlation
with the brightness of the comets.Comment: 21 pages, 4 figures, accepted for publication in A
Tumour necrosis factor-α and adenosine in endotoxin shockleading related cardiovascular symptoms
We have observed uncontrollable cardiogenic shock as a cardiovascular manifestation of systemic inflammatory response syndrome (SIRS) leading to death in a 62-year-old woman. The diagnosis of SIRS was based on the demonstration of endotoxinaemia, and highly elevated plasma levels of tumour necrosis factor (TNF)-α, and interleukin (IL)-10. We suggest that these cytokines may contribute to the terminal SIRS-related arrythmias, impaired myocardial contractility, as well as increased vascular permeability. In addition, the increased production of adenosine, a counter-regulatory mediator of inflammation, may also play a role in cardiodepression. We suggest a relationship between the action of TNF-α , IL-10 and adenosine in the pathogenesis of circulatory symptoms described above
- âŠ