297 research outputs found
Development of Proteomics-Based Fungicides: New Strategies for Environmentally Friendly Control of Fungal Plant Diseases
Proteomics has become one of the most relevant high-throughput technologies. Several approaches have been used for studying, for example, tumor development, biomarker discovery, or microbiology. In this “post-genomic” era, the relevance of these studies has been highlighted as the phenotypes determined by the proteins and not by the genotypes encoding them that is responsible for the final phenotypes. One of the most interesting outcomes of these technologies is the design of new drugs, due to the discovery of new disease factors that may be candidates for new therapeutic targets. To our knowledge, no commercial fungicides have been developed from targeted molecular research, this review will shed some light on future prospects. We will summarize previous research efforts and discuss future innovations, focused on the fight against one of the main agents causing a devastating crops disease, fungal phytopathogens
Nonthermal Radiation from Type Ia Supernova Remnants
We present calculations of expected continuum emissions from Sedov-Taylor
phase Type Ia supernova remnants (SNRs), using the energy spectra of cosmic ray
(CR) electrons and protons from nonlinear diffusive shock acceleration (DSA)
simulations. A new, general-purpose radiative process code, Cosmicp, was
employed to calculate the radiation expected from CR electrons and protons and
their secondary products. These radio, X-ray and gamma-ray emissions are
generally consistent with current observations of Type Ia SNRs. The emissions
from electrons in these models dominate the radio through X-ray bands. Decays
of \pi^0 s from p-p collisions mostly dominate the gamma-ray range, although
for a hot, low density ISM case (n_{ISM}=0.003 cm^{-3}), the pion decay
contribution is reduced sufficiently to reveal the inverse Compton contribution
to TeV gamma-rays. In addition, we present simple scalings for the contributing
emission processes to allow a crude exploration of model parameter space,
enabling these results to be used more broadly. We also discuss the radial
surface brightness profiles expected for these model SNRs in the X-ray and
gamma-ray bands.Comment: 37 pages, 7 figures, accepted in MNRA
XCAT-GAN for Synthesizing 3D Consistent Labeled Cardiac MR Images on Anatomically Variable XCAT Phantoms
Generative adversarial networks (GANs) have provided promising data
enrichment solutions by synthesizing high-fidelity images. However, generating
large sets of labeled images with new anatomical variations remains unexplored.
We propose a novel method for synthesizing cardiac magnetic resonance (CMR)
images on a population of virtual subjects with a large anatomical variation,
introduced using the 4D eXtended Cardiac and Torso (XCAT) computerized human
phantom. We investigate two conditional image synthesis approaches grounded on
a semantically-consistent mask-guided image generation technique: 4-class and
8-class XCAT-GANs. The 4-class technique relies on only the annotations of the
heart; while the 8-class technique employs a predicted multi-tissue label map
of the heart-surrounding organs and provides better guidance for our
conditional image synthesis. For both techniques, we train our conditional
XCAT-GAN with real images paired with corresponding labels and subsequently at
the inference time, we substitute the labels with the XCAT derived ones.
Therefore, the trained network accurately transfers the tissue-specific
textures to the new label maps. By creating 33 virtual subjects of synthetic
CMR images at the end-diastolic and end-systolic phases, we evaluate the
usefulness of such data in the downstream cardiac cavity segmentation task
under different augmentation strategies. Results demonstrate that even with
only 20% of real images (40 volumes) seen during training, segmentation
performance is retained with the addition of synthetic CMR images. Moreover,
the improvement in utilizing synthetic images for augmenting the real data is
evident through the reduction of Hausdorff distance up to 28% and an increase
in the Dice score up to 5%, indicating a higher similarity to the ground truth
in all dimensions.Comment: Accepted for MICCAI 202
Results from PAMELA, ATIC and FERMI : Pulsars or Dark Matter ?
It is well known that the dark matter dominates the dynamics of galaxies and
clusters of galaxies. Its constituents remain a mystery despite an assiduous
search for them over the past three decades. Recent results from the
satellite-based PAMELA experiment detect an excess in the positron fraction at
energies between 10-100 GeV in the secondary cosmic ray spectrum. Other
experiments namely ATIC, HESS and FERMI show an excess in the total electron
(\ps + \el) spectrum for energies greater 100 GeV. These excesses in the
positron fraction as well as the electron spectrum could arise in local
astrophysical processes like pulsars, or can be attributed to the annihilation
of the dark matter particles. The second possibility gives clues to the
possible candidates for the dark matter in galaxies and other astrophysical
systems. In this article, we give a report of these exciting developments.Comment: 27 Pages, extensively revised and significantly extended, to appear
in Pramana as topical revie
Recommended from our members
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA.
The NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{μ} beam at a distance of 810 km. Using 12.33×10^{20} protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν[over ¯]_{μ}→ν[over ¯]_{e} candidates with a background of 10.3 and 102 ν[over ¯]_{μ}→ν[over ¯]_{μ} candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm_{32}^{2}|=2.48_{-0.06}^{+0.11}×10^{-3} eV^{2}/c^{4} and sin^{2}θ_{23} in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δ_{CP}=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ_{23} values in the upper octant by 1.6σ
Recommended from our members
Observation of seasonal variation of atmospheric multiple-muon events in the NOvA Near Detector
Using two years of data from the NOvA Near Detector at Fermilab, we report a seasonal variation of cosmic ray induced multiple-muon (Nμ≥2) event rates which has an opposite phase to the seasonal variation in the atmospheric temperature. The strength of the seasonal multiple-muon variation is shown to increase as a function of the muon multiplicity. However, no significant dependence of the strength of the seasonal variation of the multiple-muon variation is seen as a function of the muon zenith angle, or the spatial or angular separation between the correlated muons
Phylogenetic and Morphologic Analyses of a Coastal Fish Reveals a Marine Biogeographic Break of Terrestrial Origin in the Southern Caribbean
Marine allopatric speciation involves interplay between intrinsic organismal properties and extrinsic factors. However, the relative contribution of each depends on the taxon under study and its geographic context. Utilizing sea catfishes in the Cathorops mapale species group, this study tests the hypothesis that both reproductive strategies conferring limited dispersal opportunities and an apparent geomorphologic barrier in the Southern Caribbean have promoted speciation in this group from a little studied area of the world.Mitochondrial gene sequences were obtained from representatives of the Cathorops mapale species group across its distributional range from Colombia to Venezuela. Morphometric and meristic analyses were also done to assess morphologic variation. Along a approximately 2000 km transect, two major lineages, Cathorops sp. and C. mapale, were identified by levels of genetic differentiation, phylogenetic reconstructions, and morphological analyses. The lineages are separated by approximately 150 km at the Santa Marta Massif (SMM) in Colombia. The northward displacement of the SMM into the Caribbean in the early Pleistocene altered the geomorphology of the continental margin, ultimately disrupting the natural habitat of C. mapale. The estimated approximately 0.86 my divergence of the lineages from a common ancestor coincides with the timing of the SMM displacement at approximately 0.78 my.Results presented here support the hypothesis that organismal properties as well as extrinsic factors lead to diversification of the Cathorops mapale group along the northern coast of South America. While a lack of pelagic larval stages and ecological specialization are forces impacting this process, the identification of the SMM as contributing to allopatric speciation in marine organisms adds to the list of recognized barriers in the Caribbean. Comparative examination of additional Southern Caribbean taxa, particularly those with varying life history traits and dispersal capabilities, will determine the extent by which the SMM has influenced marine phylogeography in the region
Radio emission from Supernova Remnants
The explosion of a supernova releases almost instantaneously about 10^51 ergs
of mechanic energy, changing irreversibly the physical and chemical properties
of large regions in the galaxies. The stellar ejecta, the nebula resulting from
the powerful shock waves, and sometimes a compact stellar remnant, constitute a
supernova remnant (SNR). They can radiate their energy across the whole
electromagnetic spectrum, but the great majority are radio sources. Almost 70
years after the first detection of radio emission coming from a SNR, great
progress has been achieved in the comprehension of their physical
characteristics and evolution. We review the present knowledge of different
aspects of radio remnants, focusing on sources of the Milky Way and the
Magellanic Clouds, where the SNRs can be spatially resolved. We present a brief
overview of theoretical background, analyze morphology and polarization
properties, and review and critical discuss different methods applied to
determine the radio spectrum and distances. The consequences of the interaction
between the SNR shocks and the surrounding medium are examined, including the
question of whether SNRs can trigger the formation of new stars. Cases of
multispectral comparison are presented. A section is devoted to reviewing
recent results of radio SNRs in the Magellanic Clouds, with particular emphasis
on the radio properties of SN 1987A, an ideal laboratory to investigate
dynamical evolution of an SNR in near real time. The review concludes with a
summary of issues on radio SNRs that deserve further study, and analyzing the
prospects for future research with the latest generation radio telescopes.Comment: Revised version. 48 pages, 15 figure
Interlaboratory Coverage Test on Plant Food Bioactive Compounds and their Metabolites by Mass Spectrometry-Based Untargeted Metabolomics.
Bioactive compounds present in plant-based foods, and their metabolites derived from gut microbiota and endogenous metabolism, represent thousands of chemical structures of potential interest for human nutrition and health. State-of-the-art analytical methodologies, including untargeted metabolomics based on high-resolution mass spectrometry, are required for the profiling of these compounds in complex matrices, including plant food materials and biofluids. The aim of this project was to compare the analytical coverage of untargeted metabolomics methods independently developed and employed in various European platforms. In total, 56 chemical standards representing the most common classes of bioactive compounds spread over a wide chemical space were selected and analyzed by the participating platforms (n = 13) using their preferred untargeted method. The results were used to define analytical criteria for a successful analysis of plant food bioactives. Furthermore, they will serve as a basis for an optimized consensus method
Violence witnessing, perpetrating and victimization in medellin, Colombia: a random population survey
<p>Abstract</p> <p>Background</p> <p>The burden of injury from violence and the costs attributable to violence are extremely high in Colombia. Despite a dramatic decline in homicides over the last ten years, homicide rate in Medellin, Colombia second largest city continues to rank among the highest of cities in Latin America. This study aims to estimate the prevalence and distribution of witnesses, victims and perpetrators of different forms of interpersonal violence in a representative sample of the general population in Medellin in 2007.</p> <p>Methods</p> <p>A face-to-face survey was carried out on a random selected, non-institutionalized population aged 12 to 60 years, with a response rate of 91% yielding 2,095 interview responses.</p> <p>Results</p> <p>We present the rates of prevalence for having been a witness, victim, or perpetrator for different forms of violence standardized using the WHO truncated population pyramid to allow for cross-national comparison. We also present data on verbal aggression, fraud and deception, yelling and heavy pranks, unarmed aggression during last year, and armed threat, other severe threats, robbery, armed physical aggression, and sexual aggression during the lifetime, by age, sex, marital and socioeconomic status, and education. Men reported the highest prevalence of being victims, perpetrators and witnesses in all forms of violence, except for robbery and sexual violence. The number of victims per perpetrator was positively correlated with the severity of the type of violence. The highest victimization proportions over the previous twelve months occurred among minors. Perpetrators are typically young unmarried males from lower socio-economic strata.</p> <p>Conclusions</p> <p>Due to very low proportion of victimization report to authorities, periodic surveys should be included in systems for epidemiological monitoring of violence, not only of victimization but also for perpetrators. Victimization information allows quantifying the magnitude of different forms of violence, while data on factors associated with aggression and perpetrators are necessary to estimate risk and protective factors that are essential to sound policies for violence prevention formulation.</p
- …