691 research outputs found
Occurrence and distribution of Armillaria gallica genets in a declining oak stand of southern Italy
Outbreaks of Armillaria root rot in conifer plantations and declining oak stands are frequently due to the
spread of the fungus in the soil over long periods. This paper examines the occurrence and distribution of Armillaria
genets in a declining mixed oak stand of southern Italy. Samples of rhizomorphs, mycelial mats and fruit bodies of
Armillaria were collected from the soil, stumps, and living and dead trees. A total of 111 Armillaria isolates were
collected, all belonging to the species A. gallica. They were grouped in 28 genets by somatic incompatibility. The
largest genet covered an area of about 2.6 ha with a linear extent of 300 m. On the basis of an estimated 0.5 m annual
growth in the soil, its age was assumed to be about 3 centuries. The results confirm the ability of A. gallica to remain
alive and stable in a large area over a long time
Comparison of Different Methods of Automated Landform Classification at the Drainage Basin Scale: Examples from the Southern Italy
In this work, we tested the reliability of two different methods of
automated landform classification (ACL) in three geological domains of the
southern Italian chain with contrasting morphological features. ACL maps
deriving from the TPI-based (topographic position index) algorithm are strictly
dependent to the search input parameters and they are not able to fully capture
landforms of different size. Geomorphons-based classification has shown a
higher potential and can represent a powerful method of ACL, although it
should be improved with the introduction of additional DEM-based parameters
for the extraction of landform classe
ISO observations of four active galaxies
We present ISO PHOT-S spectra of four galaxies known or suspected to host a
central AGN, selected from the initial Iras/Rosat sample of Boller et al.
(1992). Two of them had no obvious Seyfert features in their previous optical
spectra: IRAS 14201+2956, and IRAS 21582+1018. The latter was bright enough to
also allow SWS observations around selected neon lines, to establish its
excitation. While both PHOT-S spectra are characteristic of starburst-dominated
galaxies, the neon line ratios in IRAS 21582+1018 indicate the presence of a
hard excitation source. New, high-resolution, optical spectra show only a weak,
broad component around Halpha, classifying now these two objects as Sey 1.9
galaxies. The two other galaxies observed are the NLS1 galaxies Mrk 359 and Mrk
1388. Their ISO spectra however do not reveal the typical, strong PAH features
found in the starburst galaxies and are more like those of standard Seyferts.
These results show therefore that, although IR observations were expected to be
able to always reveal the presence of an active nucleus by piercing through the
central obscuration, the result may be ambiguous: the broad band IR energy
distribution can still be dominated by starburts located in a circumnuclear
region, and the AGN appear only in specific observations (high-excitation lines
in the IR, or optical spectra with better quality than classification spectra).
The obscuration needs however to be patchy rather than complete, to explain the
detection of the high-excitation lines or broad Balmer wings. Only high-energy
observations can then establish the strength of the central
AGN and the amount of extinction with certainty.Comment: 8 pages, 8 figures, accepted in Astronomy & Astrophysic
A Multivariate Statistical Analysis of Spiral Galaxy Luminosities. II. Morphology-Dependent Multiwavelength Emission Properties
This is the second of two papers based on a systematic multi-wavelength (X,
B, H, 12m, FIR, 6cm) statistical analysis of the {\it Einstein Observatory
Galaxy Catalog} sample of 234 `normal' S0/a-Irr galaxies. This sample is
representative of spiral galaxies (Paper I), and its wide wavelength coverage
provides a unique opportunity for a systematic exploration of the relations
among different emission bands, that can give novel insight on the different
emission processes and their relation to galaxian components, as a function of
galaxy morphology.Comment: text, 7 figs, 2 tables, submitted to Ap.
ÎČ2-Adrenergic receptor stimulation improves endothelial progenitor cell-mediated ischemic neoangiogenesis
Endothelial progenitor cells (EPCs) are present in the systemic circulation and home to sites of ischemic injury where they promote neoangiogenesis. ÎČ2-Adrenergic receptor (ÎČ2AR) plays a critical role in vascular tone regulation and neoangiogenesis
The magnetic fields of large Virgo Cluster spirals
Because of its proximity the Virgo Cluster is an excellent target for
studying interactions of galaxies with the cluster environment. Both the
high-velocity tidal interactions and effects of ram pressure stripping by the
intracluster gas can be investigated. Optical and/or \ion{H}{i} observations do
not always show effects of weak interactions between galaxies and their
encounters with the cluster medium. For this reason we searched for possible
anomalies in the magnetic field structure in Virgo Cluster spirals which could
be attributed to perturbations in their gas distribution and kinematics. Five
angularly large Virgo Cluster spiral galaxies (NGC 4501, NGC 4438, NGC 4535,
NGC 4548 and NGC 4654) were the targets for a sensitive total power and
polarization study using the 100-m radio telescope in Effelsberg at 4.85 GHz.
For two objects polarization data at higher frequencies have been obtained
allowing Faraday rotation analysis. Distorted magnetic field structures were
identified in all galaxies. Interaction-induced magnetized outflows were found
in NGC 4438 (due to nuclear activity) and NGC 4654 (a combination of tidal
tails and ram pressure effects). Almost all objects (except the anaemic NGC
4548) exhibit distortions in polarized radio continuum attributable to
influence of the ambient gas. For some galaxies they agree with observations of
other species, but sometimes (NGC 4535) the magnetic field is the only tracer
of the interaction with the cluster environment. The cluster environment
clearly affects the evolution of the galaxies due to ram pressure and tidal
effects. Magnetic fields provide a very long-lasting memory of past
interactions. Therefore, they are a good tracer of weak interactions which are
difficult to detect by other observations.Comment: 13 pages, 12 figure
Breeding effects on durum wheat traits detected using GWAS and haplotype block analysis
IntroductionThe recent boosting of genomic data in durum wheat (Triticum turgidum subsp. durum) offers the opportunity to better understand the effects of breeding on the genetic structures that regulate the expression of traits of agronomic interest. Furthermore, the identification of DNA markers useful for marker-assisted selection could also improve the reliability of technical protocols used for variety protection and registration.MethodsWithin this motivation context, 123 durum wheat accessions, classified into three groups: landraces (LR), ancient (OC) and modern cultivars (MC), were evaluated in two locations, for 34 agronomic traits, including UPOV descriptors, to assess the impact of changes that occurred during modern breeding.ResultsThe association mapping analysis, performed with 4,241 SNP markers and six multi-locus-GWAS models, revealed 28 reliable Quantitative Trait Nucleotides (QTNs) related to plant morphology and kernel-related traits. Some important genes controlling flowering time and plant height were in linkage disequilibrium (LD) decay with QTNs identified in this study. A strong association for yellow berry was found on chromosome 6A (Q.Yb-6A) in a region containing the nadh-ubiquinone oxidoreductase subunit, a gene involved in starch metabolism. The Q.Kcp-2A harbored the PPO locus, with the associated marker (Ku_c13700_1196) in LD decay with Ppo-A1 and Ppo-A2. Interestingly, the Q.FGSGls-2B.1, identified by RAC875_c34512_685 for flag leaf glaucosity, mapped less than 1 Mb from the Epistatic inhibitors of glaucousness (Iw1), thus representing a good candidate for supporting the morphological DUS traits also with molecular markers. LD haplotype block approach revealed a higher diversity, richness and length of haploblocks in MC than OC and LR (580 in LR, 585 in OC and 612 in MC), suggesting a possible effect exerted by breeding programs on genomic regions associated with the agronomic traits.DiscussionOur findings pave new ways to support the phenotypic characterization necessary for variety registration by using a panel of cost-effectiveness SNP markers associated also to the UPOV descriptors. Moreover, the panel of associated SNPs might represent a reservoir of favourable alleles to use in durum wheat breeding and genetics
Tools for Semi-automated Landform Classification: A Comparison in the Basilicata Region (Southern Italy)
Recent advances in spatial methods of digital elevation model
(DEMs) analysis have addressed many research topics on the assessment of
morphometric parameters of the landscape. Development of computer algorithms for calculating the geomorphometric properties of the Earthâs surface has
allowed for expanding of some methods in the semi-automatic recognition and
classification of landscape features. In such a way, several papers have been
produced, documenting the applicability of the landform classification based on
map algebra. The Topographic Position Index (TPI) is one of the most widely
used parameters for semi-automated landform classification using GIS software.
The aim was to apply the TPI classes for landform classification in the Basilicata
Region (Southern Italy). The Basilicata Region is characterized by an extremely
heterogeneous landscape and geological features. The automated landform
extraction, starting from two different resolution DEMs at 20 and 5 m-grids, has
been carried out by using three different GIS software: Arcview, Arcmap, and
SAGA. Comparison of the landform maps resulting from each software at a
different scale has been realized, furnishing at the end the best landform map and
consequently a discussion over which is the best software implementation of the
TPI method
Physiological aspects of the determination of comprehensive arterial inflows in the lower abdomen assessed by Doppler ultrasound
Non-invasive measurement of splanchnic hemodynamics has been utilized in the clinical setting for diagnosis of gastro-intestinal disease, and for determining reserve blood flow (BF) distribution. However, previous studies that measured BF in a "single vessel with small size volume", such as the superior mesenteric and coeliac arteries, were concerned solely with the target organ in the gastrointestinal area, and therefore evaluation of alterations in these single arterial BFs under various states was sometimes limited to "small blood volumes", even though there was a relatively large change in flow. BF in the lower abdomen (BFAb) is potentially a useful indicator of the influence of comprehensive BF redistribution in cardiovascular and hepato-gastrointestinal disease, in the postprandial period, and in relation to physical exercise. BFAb can be determined theoretically using Doppler ultrasound by subtracting BF in the bilateral proximal femoral arteries (FAs) from BF in the upper abdominal aorta (Ao) above the coeliac trunk. Prior to acceptance of this method of determining a true BFAb value, it is necessary to obtain validated normal physiological data that represent the hemodynamic relationship between the three arteries. In determining BFAb, relative reliability was acceptably high (range in intra-class correlation coefficient: 0.85-0.97) for three arterial hemodynamic parameters (blood velocity, vessel diameter, and BF) in three repeated measurements obtained over three different days. Bland-Altman analysis of the three repeated measurements revealed that day-to-day physiological variation (potentially including measurement error) was within the acceptable minimum range (95% of confidence interval), calculated as the difference in hemodynamics between two measurements. Mean BF (ml/min) was 2951 ± 767 in Ao, 316 ± 97 in left FA, 313 ± 83 in right FA, and 2323 ± 703 in BFAb, which is in agreement with a previous study that measured the sum of BF in the major part of the coeliac, mesenteric, and renal arteries. This review presents the methodological concept that underlies BFAb, and aspects of its day-to-day relative reliability in terms of the hemodynamics of the three target arteries, relationship with body surface area, respiratory effects, and potential clinical usefulness and application, in relation to data previously reported in original dedicated research
The XMM-Newton/2dF survey-VIII: The extended X-ray sources
We present a sample of eight extended X-ray sources detected in the
wide-field (~2.3 deg^2), bright (2-10 ksec) XMM-Newton/2dF survey, reaching a
flux limit of ~2 X 10^{-14} erg/s/cm^2. Of these, seven are identified as
secure X-ray clusters in the soft 0.3-2 keV band using a standard wavelet
algorithm on either the PN or the MOS images. Spectroscopic or photometric
redshifts are available for five clusters, spanning a range between 0.12 and
0.68. The X-ray spectral fittings show temperatures between 1 and 4.6 keV,
characteristic of poor clusters and groups of galaxies. We derive for the first
time the XMM-Newton cluster number count log N-log S distribution albeit with
poor statistics. Both the log N-\log S and the Luminosity-Temperature relation
are in good agreement with previous ROSAT results.Comment: 8 pages, MNRAS in pres
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