1,031 research outputs found
Host Range of Meloidogyne Arenaria (NEAL, 1889) Chitwood, 1949 (Nematoda: Meloidogynidae) in Spain
11 páginas, ilustraciones y tablas estadĂsticas.The distribution of Meloidogyne arenaria in Spain was revised and new samples collected from representative
areas. Species and races of the populations were determined by morphometrics, differential host tests and SCAR-PCR.
Meloidogyne arenaria was found most often in warm areas, but it can occur in Northern Spain in greenhouses. A total of
125 citations were found, corresponding to 45 different host plants, of which 41 new reports (32.8%) are from this study.
The populations studied belong to race 2, which reproduces on tomato plants carrying the Mi gene, or race 3, which
reproduces on both resistant pepper and tomato. The most frequent hosts were vegetables, fruit trees, tobacco, grapevine,
and weeds.INIA OT-
03-006C7-4 and RTA2007-00099-C00-00; Castilla
La Mancha PAI09-0010-4701, INCRECYT CICyT CTM2006-07309.Peer reviewe
Can solid body destruction explain abundance discrepancies in planetary nebulae?
In planetary nebulae, abundances of oxygen and other heavy elements derived
from optical recombination lines are systematically higher than those derived
from collisionally excited lines. We investigate the hypothesis that the
destruction of solid bodies may produce pockets of cool, high-metallicity gas
that could explain these abundance discrepancies. Under the assumption of
maximally efficient radiative ablation, we derive two fundamental constraints
that the solid bodies must satisfy in order that their evaporation during the
planetary nebula phase should generate a high enough gas phase metallicity. A
local constraint implies that the bodies must be larger than tens of meters,
while a global constraint implies that the total mass of the solid body
reservoir must exceed a few hundredths of a solar mass. This mass greatly
exceeds the mass of any population of comets or large debris particles expected
to be found orbiting evolved low- to intermediate-mass stars. We therefore
conclude that contemporaneous solid body destruction cannot explain the
observed abundance discrepancies in planetary nebulae. However, similar
arguments applied to the sublimation of solid bodies during the preceding
asymptotic giant branch (AGB) phase do not lead to such a clear-cut conclusion.
In this case, the required reservoir of volatile solids is only one
ten-thousandth of a solar mass, which is comparable to the most massive debris
disks observed around solar-type stars, implying that this mechanism may
contribute to abundance discrepancies in at least some planetary nebulae, so
long as mixing of the high metallicity gas is inefficient.Comment: 8 pages, no figures, ApJ in pres
The Effects of Gas on Morphological Transformation in Mergers: Implications for Bulge and Disk Demographics
Transformation of disks into spheroids via mergers is a well-accepted element
of galaxy formation models. However, recent simulations have shown that bulge
formation is suppressed in increasingly gas-rich mergers. We investigate the
global implications of these results in a cosmological framework, using
independent approaches: empirical halo-occupation models (where galaxies are
populated in halos according to observations) and semi-analytic models. In
both, ignoring the effects of gas in mergers leads to the over-production of
spheroids: low and intermediate-mass galaxies are predicted to be
bulge-dominated (B/T~0.5 at <10^10 M_sun), with almost no bulgeless systems),
even if they have avoided major mergers. Including the different physical
behavior of gas in mergers immediately leads to a dramatic change: bulge
formation is suppressed in low-mass galaxies, observed to be gas-rich (giving
B/T~0.1 at <10^10 M_sun, with a number of bulgeless galaxies in good agreement
with observations). Simulations and analytic models which neglect the
similarity-breaking behavior of gas have difficulty reproducing the strong
observed morphology-mass relation. However, the observed dependence of gas
fractions on mass, combined with suppression of bulge formation in gas-rich
mergers, naturally leads to the observed trends. Discrepancies between
observations and models that ignore the role of gas increase with redshift; in
models that treat gas properly, galaxies are predicted to be less
bulge-dominated at high redshifts, in agreement with the observations. We
discuss implications for the global bulge mass density and future observational
tests.Comment: 14 pages, 11 figures, accepted to MNRAS (matched published version).
A routine to return the galaxy merger rates discussed here is available at
http://www.cfa.harvard.edu/~phopkins/Site/mergercalc.htm
Symmetry characterization of eigenstates in opal-based photonic crystals
The complete symmetry characterization of eigenstates in bare opal systems is
obtained by means of group theory. This symmetry assignment has allowed us to
identify several bands that cannot couple with an incident external plane wave.
Our prediction is supported by layer-KKR calculations, which are also
performed: the coupling coefficients between bulk modes and externally excited
field tend to zero when symmetry properties mismatch.Comment: 7 pages, 5 figures, submitted to Physical Review
Fate of drugs during wastewater treatment
This is the post-print version of the final paper published in TrAC Trends in Analytical Chemistry. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2013 Elsevier B.V.Recent trends in the determination of pharmaceutical drugs in wastewaters focus on the development of rapid multi-residue methods. This review addresses recent analytical trends in drug determination in environmental matrices used to facilitate fate studies. Analytical requirements for further fate evaluation and tertiary process selection and optimization are also discussed.EPSRC, Northumbrian Water, Anglian
Water, Severn Trent Water, Yorkshire Water, and United Utilities
AGN-Host Galaxy Connection: Morphology and Colours of X-ray Selected AGN at z < 2
The connection between AGN and their host galaxies has been widely studied
over recent years, showing it to be of great importance for providing answers
to some fundamental questions related with AGN fueling mechanisms, their
formation and evolution. Using X-ray and one of the deepest broad-band optical
data sets, we studied morphology and colours in relationship with X-ray
properties for sources at redshifts z < 2.0, using a sample of 262 AGN in the
Subaru/XMM-Newton Deep Survey (SXDS). Morphological classification was obtained
using the galSVM code, one of the new methods useful especially when dealing
with high-redshift sources and low-resolution data. Colour-magnitude diagrams
were studied in relationship with redshift, morphology, X-ray obscuration, and
X-ray-to-optical flux ratio. Finally, the significance of different regions was
analysed on colour-magnitude diagrams, relating the observed properties of AGN
populations with some models of their formation and evolution.Comment: 24 pages, 19 figures, accepted for publication in
Astronomy&Astrophysic
Beyond the required LISA free-fall performance: new LISA pathfinder results down to 20  μHz
In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to 20  μHz. The Letter presents the measured differential acceleration noise figure, which is at (1.74±0.05)  fm s^{-2}/sqrt[Hz] above 2 mHz and (6±1)×10  fm s^{-2}/sqrt[Hz] at 20  μHz, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency
Some topological cardinal inequalities for spaces Cp(X)
Using the index of Nagami we get new topological cardinal inequalities for spaces Cp(X).
A particular case of Theorem 1 states that if L ⊆ Cp(X) is a Lindelöf Σ-space and the
Nagami index Nag(X) of X is less or equal than the density d(L) of L (which holds for
instance if X is a Lindelöf Σ-space), then (i) there exists a completely regular Hausdorff
space Y such that Nag(Y ) Nag(X), L ⊂ Cp(Y ) and d(L) = d(Y ); (ii) Y admits a weaker
completely regular Hausdorff topology Ď„ such that w(Y , Ď„
) d(Y ) = d(L). This applies,
among other things, to characterize analytic sets for the weak topology of any locally
convex space E in a large class G of locally convex spaces that includes (DF)-spaces
and (LF)-spaces. The latter yields a result of Cascales–Orihuela about weak metrizability
of weakly compact sets in spaces from the class G.The research was supported for the second named author by National Center of Science, Poland, Grant No. N N201 605340 and for the third author by the project MTM2010-12374-E (complementary action) of the Spanish Ministry of Science and Innovation.Ferrando, JC.; Kakol, J.; López Pellicer, M.; Muñoz, M. (2013). Some topological cardinal inequalities for spaces Cp(X). Topology and its Applications. 160(10):1102-1107. https://doi.org/10.1016/j.topol.2013.04.024S110211071601
MASSIV: Mass Assembly Survey with SINFONI in VVDS. IV. Fundamental relations of star-forming galaxies at 1<z< 1.6
How mass assembly occurs in galaxies and which process(es) contribute to this
activity are among the most highly debated questions in galaxy formation
theories. This has motivated our survey MASSIV of 0.9<z<1.9 star-forming
galaxies selected from the purely flux-limited VVDS redshift survey. For the
first time, we derive the relations between galaxy size, mass, and internal
velocity, and the baryonic Tully-Fisher relation, from a statistically
representative sample of star-forming galaxies. We find a dynamical mass that
agrees with those of rotating galaxies containing a gas fraction of ~20%,
perfectly consistent with the content derived using the Kennicutt-Schmidt
formulation and the expected evolution. Non-rotating galaxies have more compact
sizes for their stellar component, and are less massive than rotators, but do
not have statistically different sizes for their gas-component. We measure a
marginal evolution in the size-stellar mass and size-velocity relations in
which discs become evenly smaller with cosmic time at fixed stellar mass or
velocity, and are less massive at a given velocity than in the local Universe.
The scatter in the Tully-Fisher relation is smaller when we introduce the S05
index, which we interpret as evidence of an increase in the contribution to
galactic kinematics of turbulent motions with cosmic time. We report a
persistently large scatter for rotators in our relations, that we suggest is
intrinsic, and possibly caused by complex physical mechanism(s) at work in our
stellar mass/luminosity regime and redshift range. Our results consistently
point towards a mild, net evolution of these relations, comparable to those
predicted by cosmological simulations of disc formation for at least 8Gyr and a
dark halo strongly coupled with galactic spectrophotometric properties
Platelets Regulate Pulmonary Inflammation and Tissue Destruction in Tuberculosis.
RATIONALE: Platelets may interact with the immune system in tuberculosis (TB) to regulate human inflammatory responses that lead to morbidity and spread of infection. OBJECTIVES: To identify a functional role of platelets in the innate inflammatory and matrix-degrading response in TB. METHODS: Markers of platelet activation were examined in plasma from 50 patients with TB before treatment and 50 control subjects. Twenty-five patients were followed longitudinally. Platelet-monocyte interactions were studied in a coculture model infected with live, virulent Mycobacterium tuberculosis (M.tb) and dissected using qRT-PCR, Luminex multiplex arrays, matrix degradation assays, and colony counts. Immunohistochemistry detected CD41 (cluster of differentiation 41) expression in a pulmonary TB murine model, and secreted platelet factors were measured in BAL fluid from 15 patients with TB and matched control subjects. MEASUREMENTS AND MAIN RESULTS: Five of six platelet-associated mediators were upregulated in plasma of patients with TB compared with control subjects, with concentrations returning to baseline by Day 60 of treatment. Gene expression of the monocyte collagenase MMP-1 (matrix metalloproteinase-1) was upregulated by platelets in M.tb infection. Platelets also enhanced M.tb-induced MMP-1 and -10 secretion, which drove type I collagen degradation. Platelets increased monocyte IL-1 and IL-10 and decreased IL-12 and MDC (monocyte-derived chemokine; also known as CCL-22) secretion, as consistent with an M2 monocyte phenotype. Monocyte killing of intracellular M.tb was decreased. In the lung, platelets were detected in a TB mouse model, and secreted platelet mediators were upregulated in human BAL fluid and correlated with MMP and IL-1β concentrations. CONCLUSIONS: Platelets drive a proinflammatory, tissue-degrading phenotype in TB
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