2,212 research outputs found
Fungal microbiota from rain water and pathogenicity of Fusarium species isolated from atmospheric dust and rainfall dust
In order to determine the presence of Fusarium spp. in atmospheric dust and rainfall dust, samples were collected during September 2007, and July, August, and October 2008. The results reveal the prevalence of airborne Fusarium species coming from the atmosphere of the South East coast of Spain. Five different Fusarium species were isolated from the settling dust: Fusarium oxysporum, F. solani, F. equiseti, F. dimerum, and F. proliferatum. Moreover, rainwater samples were obtained during significant rainfall events in January and February 2009. Using the dilution-plate method, 12 fungal genera were identified from these rainwater samples. Specific analyses of the rainwater revealed the presence of three species of Fusarium: F. oxysporum, F. proliferatum and F. equiseti. A total of 57 isolates of Fusarium spp. obtained from both rainwater and atmospheric rainfall dust sampling were inoculated onto melon (Cucumis melo L.) cv. Piñonet and tomato (Lycopersicon esculentum Mill.) cv. San Pedro. These species were chosen because they are the main herbaceous crops in Almeria province. The results presented in this work indicate strongly that spores or propagules of Fusarium are able to cross the continental barrier carried by winds from the Sahara (Africa) to crop or coastal lands in Europe. Results show differences in the pathogenicity of the isolates tested. Both hosts showed root rot when inoculated with different species of Fusarium, although fresh weight measurements did not bring any information about the pathogenicity. The findings presented above are strong indications that long-distance transmission of Fusarium propagules may occur. Diseases caused by species of Fusarium are common in these areas. They were in the past, and are still today, a problem for greenhouses crops in Almería, and many species have been listed as pathogens on agricultural crops in this region. Saharan air masses dominate the Mediterranean regions. The evidence of long distance dispersal of Fusarium spp. by atmospheric dust and rainwater together with their proved pathogenicity must be taken into account in epidemiological studies
Growth, History, or Institutions? What Explains State Fragilityin Sub-Saharan Africa
We explore the determinants of state fragility in sub-Saharan Africa. Controlling for a wide range of
economic, demographic, geographic and istitutional regressors, we find that institutions, and in
particular the civil liberties index and the number of revolutions, are the main determinants of
fragility, even taking into account their potential endogeneity. Economic factors such as income
growth and investment display a non robust impact after controlling for omitted variables and
reverse causality. Colonial variables reflecting the history of the region display a marginal impact
on fragility once institutions are accounted for
The Fragile Definition of State Fragility
We investigates the link between fragility and economic development in sub-Saharan Africa over a
yearly panel including 28 countries for the 1999-2004 period. Beside the conventional definition of
fragility adopted by the OECD Development Assistance Committee, we introduce the more severe
definition of extreme fragility. We show that only the latter exerts a significantly negative impact on
economic development, once standard economic, demographic, and institutional regressors are
accounted for. As a by-product of this investigation we produce up-to-date evidence on the growth
performance of the area. We find a tendency to convergence and no influence of geographic and
historical factors
Search for anomalies in the neutrino sector with muon spectrometers and large LArTPC imaging detectors at CERN
A new experiment with an intense ~2 GeV neutrino beam at CERN SPS is proposed
in order to definitely clarify the possible existence of additional neutrino
states, as pointed out by neutrino calibration source experiments, reactor and
accelerator experiments and measure the corresponding oscillation parameters.
The experiment is based on two identical LAr-TPCs complemented by magnetized
spectrometers detecting electron and muon neutrino events at Far and Near
positions, 1600 m and 300 m from the proton target, respectively. The ICARUS
T600 detector, the largest LAr-TPC ever built with a size of about 600 ton of
imaging mass, now running in the LNGS underground laboratory, will be moved at
the CERN Far position. An additional 1/4 of the T600 detector (T150) will be
constructed and located in the Near position. Two large area spectrometers will
be placed downstream of the two LAr-TPC detectors to perform charge
identification and muon momentum measurements from sub-GeV to several GeV
energy range, greatly complementing the physics capabilities. This experiment
will offer remarkable discovery potentialities, collecting a very large number
of unbiased events both in the neutrino and antineutrino channels, largely
adequate to definitely settle the origin of the observed neutrino-related
anomalies.Comment: Contribution to the European Strategy for Particle Physics - Open
Symposium Preparatory Group, Kracow 10-12 September 201
INFN What Next: Ultra-relativistic Heavy-Ion Collisions
This document was prepared by the community that is active in Italy, within
INFN (Istituto Nazionale di Fisica Nucleare), in the field of
ultra-relativistic heavy-ion collisions. The experimental study of the phase
diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP)
deconfined state will proceed, in the next 10-15 years, along two directions:
the high-energy regime at RHIC and at the LHC, and the low-energy regime at
FAIR, NICA, SPS and RHIC. The Italian community is strongly involved in the
present and future programme of the ALICE experiment, the upgrade of which will
open, in the 2020s, a new phase of high-precision characterisation of the QGP
properties at the LHC. As a complement of this main activity, there is a
growing interest in a possible future experiment at the SPS, which would target
the search for the onset of deconfinement using dimuon measurements. On a
longer timescale, the community looks with interest at the ongoing studies and
discussions on a possible fixed-target programme using the LHC ion beams and on
the Future Circular Collider.Comment: 99 pages, 56 figure
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
Prospects for the measurement of muon-neutrino disappearance at the FNAL-Booster
Neutrino physics is nowadays receiving more and more attention as a possible
source of information for the long-standing problem of new physics beyond the
Standard Model. The recent measurement of the mixing angle in the
standard mixing oscillation scenario encourages us to pursue the still missing
results on leptonic CP violation and absolute neutrino masses. However,
puzzling measurements exist that deserve an exhaustive evaluation. The NESSiE
Collaboration has been setup to undertake conclusive experiments to clarify the
muon-neutrino disappearance measurements at small , which will be able to
put severe constraints to models with more than the three-standard neutrinos,
or even to robustly measure the presence of a new kind of neutrino oscillation
for the first time. To this aim the use of the current FNAL-Booster neutrino
beam for a Short-Baseline experiment has been carefully evaluated. This
proposal refers to the use of magnetic spectrometers at two different sites,
Near and Far. Their positions have been extensively studied, together with the
possible performances of two OPERA-like spectrometers. The proposal is
constrained by availability of existing hardware and a time-schedule compatible
with the CERN project for a new more performant neutrino beam, which will
nicely extend the physics results achievable at the Booster. The possible FNAL
experiment will allow to clarify the current disappearance tension
with appearance and disappearance at the eV mass scale. Instead, a new
CERN neutrino beam would allow a further span in the parameter space together
with a refined control of systematics and, more relevant, the measurement of
the antineutrino sector, by upgrading the spectrometer with detectors currently
under R&D study.Comment: 76 pages, 52 figure
Performance and Operation of the CMS Electromagnetic Calorimeter
The operation and general performance of the CMS electromagnetic calorimeter
using cosmic-ray muons are described. These muons were recorded after the
closure of the CMS detector in late 2008. The calorimeter is made of lead
tungstate crystals and the overall status of the 75848 channels corresponding
to the barrel and endcap detectors is reported. The stability of crucial
operational parameters, such as high voltage, temperature and electronic noise,
is summarised and the performance of the light monitoring system is presented
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