5,963 research outputs found
Localization properties of driven disordered one-dimensional systems
We generalize the definition of localization length to disordered systems
driven by a time-periodic potential using a Floquet-Green function formalism.
We study its dependence on the amplitude and frequency of the driving field in
a one-dimensional tight-binding model with different amounts of disorder in the
lattice. As compared to the autonomous system, the localization length for the
driven system can increase or decrease depending on the frequency of the
driving. We investigate the dependence of the localization length with the
particle's energy and prove that it is always periodic. Its maximum is not
necessarily at the band center as in the non-driven case. We study the
adiabatic limit by introducing a phenomenological inelastic scattering rate
which limits the delocalizing effect of low-frequency fields.Comment: Accepted for publication in European Physical Journal
Three body systems with strangeness and exotic systems
We report on four 's and three 's, in the 1500 - 1800 MeV
region, as two meson - one baryon S-wave resonances found by solving
the Faddeev equations in the coupled channel approach, which can be associated
to the existing = -1, low lying baryon resonances. On the
other hand we also report on a new, hidden strangeness state, mostly made
of , with mass around 1920 MeV, which we think could be
responsible for the peak seen in the around this
energy. Finally we address a very novel topic in which we show how few body
systems of several mesons can be produced, with their spins aligned up
to J=6, and how these states found theoretically can be associated to several
known mesons with spins J=2,3,4,5,6.Comment: Talk at the 21st European Conference on Few Body Problems in Physics,
Salamanca, Sep. 201
Exploring host genetic polymorphisms involved in SARS-CoV infection autcomes: implications for personalized medicine in COVID-19
Objective. To systematically explore genetic polymorphisms associated with the clinical outcomes in SARS-CoV infection in
humans. Methods. This comprehensive literature search comprised available English papers published in PubMed/Medline and
SCOPUS databases following the PRISMA-P guidelines and PICO/AXIS criteria. Results. Twenty-nine polymorphisms located
in 21 genes were identified as associated with SARS-CoV susceptibility/resistance, disease severity, and clinical outcomes
predominantly in Asian populations. Thus, genes implicated in key pathophysiological processes such as the mechanisms
related to the entry of the virus into the cell and the antiviral immune/inflammatory responses were identified. Conclusions.
Although caution must be taken, the results of this systematic review suggest that multiple genetic polymorphisms are
associated with SARS-CoV infection features by affecting virus pathogenesis and host immune response, which could have
important applications for the study and understanding of genetics in SARS-CoV-2/COVID-19 and for personalized
translational clinical practice depending on the population studied and associated environments
Lights and Shadows in Evolutionary Deep Learning: Taxonomy, Critical Methodological Analysis, Cases of Study, Learned Lessons, Recommendations and Challenges
Much has been said about the fusion of bio-inspired optimization algorithms
and Deep Learning models for several purposes: from the discovery of network
topologies and hyper-parametric configurations with improved performance for a
given task, to the optimization of the model's parameters as a replacement for
gradient-based solvers. Indeed, the literature is rich in proposals showcasing
the application of assorted nature-inspired approaches for these tasks. In this
work we comprehensively review and critically examine contributions made so far
based on three axes, each addressing a fundamental question in this research
avenue: a) optimization and taxonomy (Why?), including a historical
perspective, definitions of optimization problems in Deep Learning, and a
taxonomy associated with an in-depth analysis of the literature, b) critical
methodological analysis (How?), which together with two case studies, allows us
to address learned lessons and recommendations for good practices following the
analysis of the literature, and c) challenges and new directions of research
(What can be done, and what for?). In summary, three axes - optimization and
taxonomy, critical analysis, and challenges - which outline a complete vision
of a merger of two technologies drawing up an exciting future for this area of
fusion research.Comment: 64 pages, 18 figures, under review for its consideration in
Information Fusion journa
Effect of Greenhouse Film Cover on the Development of Fungal Diseases on Tomato (Solanum lycopersicum L.) and Pepper (Capsicum annuum L.) in a Mediterranean Protected Crop
Greenhouses on the Mediterranean coast mainly use plastic materials as their cover. The
influence of light exerted by these materials directly affects the crops by modifying the environment in which they develop. The aim of this study was to analyze the effect of the use of two plastic films in an experimental greenhouse on the development of fungal diseases in two spring–summer crop cycles: tomato (Solanum lycopersicum L.) from february to July 2021 and pepper (Capsicum annuum L.) from February to July 2022. The study was carried out in Almeria (Spain) in a multispan greenhouse divided transversely into two sectors by a polyethylene sheet. A commercial film was installed in the east sector (90% of transmissivity and 55% diffusivity) and an experimental film was
installed in the west sector (85% of transmissivity and 60% diffusivity). In addition, the effect of the yield and quality of the harvested fruit was determined. In this study, two diseases were established
naturally on the crop: (i) powdery mildew (Leveillula taurica) in both the tomato and the pepper crop cycles and (ii) early blight (Alternaria solani) in the tomato. The analyses of both diseases showed that the areas of the greenhouse that used the plastic cover, which presented a lower sunlight
transmissivity, showed higher levels of disease than the areas that used the plastic cover that allowed greater transmissivity of light within the greenhouse, differing statistically in some phases of the crop. The marketable yield was 4.2% (for tomato) and 3.1% (for pepper) higher in the sector
with the experimental film with high transmissivity. For both crops, the quality of the fruits did not show statistically significant difference
The dynamics of tripartism in post-democratic transitions: comparative lessons from Spain and Poland
Maternal exposure to ozone modulates the endophyte-conferred resistance to aphids in lolium multiflorum plants
Plants are challenged by biotic and abiotic stress factors and the incidence of one can increase or decrease resistance to another. These relations can also occur transgenerationally. For instance, progeny plants whose mothers experienced herbivory can be more resistant to herbivores. Certain fungal endophytes that are vertically transmitted endow plants with alkaloids and resistance to herbivores. However, endophyte-symbiotic plants exposed to the oxidative agent ozone became susceptible to aphids. Here, we explored whether this effect persists transgenerationally. We exposed Lolium multiflorum plants with and without fungal endophyte Epichloë occultans to ozone (120 or 0 ppb), and then, challenged the progeny with aphids (Rhopalosiphum padi). The endophyte was the main factor determining the resistance to aphids, but its importance diminished in plants with ozone history. This negative ozone effect on the endophyte-mediated resistance was apparent on aphid individual weights. Phenolic compounds in seeds were increased by the symbiosis and diminished by the ozone. The endophyte effect on phenolics vanished in progeny plants while the negative ozone effect persisted. Independently of ozone, the symbiosis increased the plant biomass (≈24%). Although ozone can diminish the importance of endophyte symbiosis for plant resistance to herbivores, it would be compensated by host growth stimulation.Fil: Bubica Bustos, Ludmila Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Ueno, Andrea Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Di Leo, Tara D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Crocco, Carlos Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Martinez-Ghersa, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Molina Montenegro, Marco A.. Universidad de Talca; Chile. Universidad Católica del Norte; Chile. Universidad Católica de Maule; ChileFil: Gundel, Pedro Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Talca; Chil
NQO2 is a reactive oxygen species generating off-target for acetaminophen
[Image: see text] The analgesic and antipyretic compound acetaminophen (paracetamol) is one of the most used drugs worldwide. Acetaminophen overdose is also the most common cause for acute liver toxicity. Here we show that acetaminophen and many structurally related compounds bind quinone reductase 2 (NQO2) in vitro and in live cells, establishing NQO2 as a novel off-target. NQO2 modulates the levels of acetaminophen derived reactive oxygen species, more specifically superoxide anions, in cultured cells. In humans, NQO2 is highly expressed in liver and kidney, the main sites of acetaminophen toxicity. We suggest that NQO2 mediated superoxide production may function as a novel mechanism augmenting acetaminophen toxicity
Dynamically generated resonances from the vector octet-baryon decuplet interaction
We study the interaction of the octet of vector mesons with the decuplet of
baryons using Lagrangians of the hidden gauge theory for vector interactions.
The unitary amplitudes in coupled channels develop poles that can be associated
with some known baryonic resonances, while there are predictions for new ones
at the energy frontier of the experimental research. The work offers guidelines
on how to search for these resonances
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