Caracterización del microbioma de plantas de banano (Musa × paradisiaca L.) bajo sistemas de producción orgánico y convencional

Banana (Musa × paradisiaca L.) cultivation is one of the most important agricultural activities for many countries, and it is the primary fruit consume worldwide. Integrated soil management and fertilization programs aims to enhance soil fertility while maintaining crop yields. A large body of literature examined the changes in soil properties associated with different fertility regimens. Despite the critical role of the plant-associated microbiome in plant health and productivity, the effects of different agricultural management systems on microbial communities' response in banana are poorly understood.  This study reports the structure, diversity, and richness of the microbial community of the bulk soil, rhizosphere, and leaf of banana plants under organic and conventional management. Samples were obtained from two banana plantations located in the province of El Oro, Ecuador. The analysis was based on DNA sequencing of the V3-V4 region of the 16S rRNA gene for bacteria and the ITS2 region for fungi. Here, we found a significant effect of the management system in the bacterial and fungi community composition. In general terms, under a conventionally managed system, the richness and evenness of the bacterial and fungal community increased among the soil and rhizosphere compared to the organic farming system. Soil and rhizosphere under organic farming were associated with a higher relative abundance of Proteobacteria, Firmicutes, and Bacteroidetes and exhibited an overrepresentation of microbial genus know as plant growth-promoting, as well as genera involved in essential ecosystem processes. We also found that ASVs of the same genus respond differently to the two types of agricultural management on the soil and the rhizosphere. In comparison, the bacterial communities in the leaves were more similar in both types of management.  Understanding how long-term cropping management systems shift the microbial diversity and structure at the level of individual microbial taxa, such as presented in this research, can help to design farming systems that can maintain high profitability of the banana crops by stimulating growth-promoting bacteria and those responsible for the suppression of the soil-borne disease.El cultivo de banano (Musa × paradisiaca L.) es una de las actividades agrícolas más importantes para muchos países y es la principal fruta consumida mundialmente. La fertilización química es una de las prácticas más comunes utilizada para aumentar el rendimiento y productividad de los cultivos. Una gran cantidad de literatura examina los cambios en las propiedades del suelo asociados con diferentes regímenes de fertilización. A pesar del papel fundamental del microbioma en la salud y la productividad de las plantas, los efectos de los diferentes sistemas de gestión agrícola sobre las comunidades microbianas son poco estudiados. Este estudio informa la estructura, diversidad y riqueza de la comunidad microbiana del suelo, rizosfera y hoja de las plantas de banano bajo manejo orgánico y convencional. Se obtuvieron muestras de dos plantaciones bananeras ubicadas en El Oro, una de las provincias con mayor productividad bananera en Ecuador. El análisis se basó en la secuenciación de ADN de la región V3-V4 del gen del ARNr 16S para bacterias y la región ITS2 para hongos. Se encontró un efecto significativo del sistema de manejo en la composición de la comunidad bacteriana y fúngica. En términos generales, bajo un sistema de manejo convencional, la riqueza y uniformidad de la comunidad bacteriana y fúngica aumentó entre las muestras de suelo y rizosfera en comparación con el sistema de agricultura orgánica. El suelo y la rizosfera bajo agricultura orgánica se asociaron con una mayor abundancia relativa de Proteobacteria, Firmicutes y Bacteroidetes y exhibieron una sobrerrepresentación de géneros microbianos conocidos como promotores del crecimiento de plantas, así como géneros involucrados en procesos importantes del ecosistema. También encontramos que los ASV del mismo género responden diferente a los dos tipos de manejo agrícola en el suelo y la rizosfera. Mientras que las comunidades bacterianas en las hojas fueron más similares en ambos tipos de manejo. Comprender cómo los sistemas de gestión de cultivos a largo plazo modifican la diversidad y la estructura microbiana, como se presenta en esta investigación, puede ayudar a diseñar sistemas agrícolas que puedan mantener una alta rentabilidad de los cultivos de banano mediante la estimulación de bacterias promotoras del crecimiento y supresoras de las enfermedades transmitidas por el suelo

Radio-gamma-ray connection and spectral evolution in 4C+49.22 (S4 1150+49): the Fermi, Swift and Planck view

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope detected a strong γ-ray flare on 2011 May 15 from a source identified as 4C+49.22, a flat spectrum radio quasar (FSRQ) also known as S4 1150+49. This blazar, characterized by a prominent radio-optical-X-ray jet, was in a low γ-ray activity state during the first years of Fermi observations. Simultaneous observations during the quiescent, outburst and post-flare γ-ray states were obtained by Swift, Planck and optical-IR-radio telescopes (Instituto Nacional de Astrofísica, Óptica y Electrónica, Catalina Sky Survey, Very Long Baseline Array [VLBA], Metsähovi). The flare is observed from microwave to X-ray bands with correlated variability and the Fermi, Swift and Planck data for this FSRQ show some features more typical of BL Lac objects, like the synchrotron peak in the optical band that outshines the thermal blue-bump emission, and the X-ray spectral softening. Multi-epoch VLBA observations show the ejection of a new component close in time with the GeV γ-ray flare. The radio-to-γ-ray spectral energy distribution is modelled and fitted successfully for the outburst and the post-flare epochs using either a single flaring blob with two emission processes (synchrotron self-Compton (SSC), and external-radiation Compton), and a two-zone model with SSC-only mechanis

Charge separation relative to the reaction plane in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}= 2.76 TeV

Measurements of charge dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudo-rapidity range $|\eta| < 0.8$ are presented as a function of the collision centrality, particle separation in pseudo-rapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge dependent azimuthal correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286

Entry of spores into intestinal epithelial cells contributes to recurrence of Clostridioides difficile infection

Indexación ScopusClostridioides difficile spores produced during infection are important for the recurrence of the disease. Here, we show that C. difficile spores gain entry into the intestinal mucosa via pathways dependent on host fibronectin-α5β1 and vitronectin-αvβ1. The exosporium protein BclA3, on the spore surface, is required for both entry pathways. Deletion of the bclA3 gene in C. difficile, or pharmacological inhibition of endocytosis using nystatin, leads to reduced entry into the intestinal mucosa and reduced recurrence of the disease in a mouse model. Our findings indicate that C. difficile spore entry into the intestinal barrier can contribute to spore persistence and infection recurrence, and suggest potential avenues for new therapies. © 2021, The Author(s).https://www-nature-com.recursosbiblioteca.unab.cl/articles/s41467-021-21355-

A note on comonotonicity and positivity of the control components of decoupled quadratic FBSDE

In this small note we are concerned with the solution of Forward-Backward Stochastic Differential Equations (FBSDE) with drivers that grow quadratically in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem is a comparison result that allows comparing componentwise the signs of the control processes of two different qgFBSDE. As a byproduct one obtains conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio

Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at s=0.9\sqrt{s}=0.9, 2.76 and 7 TeV

Measurements of the sphericity of primary charged particles in minimum bias proton--proton collisions at $\sqrt{s}=0.9$, 2.76 and 7 TeV with the ALICE detector at the LHC are presented. The observable is linearized to be collinear safe and is measured in the plane perpendicular to the beam direction using primary charged tracks with $p_{\rm T}\geq0.5$ GeV/c in $|\eta|\leq0.8$. The mean sphericity as a function of the charged particle multiplicity at mid-rapidity ($N_{\rm ch}$) is reported for events with different $p_{\rm T}$ scales ("soft" and "hard") defined by the transverse momentum of the leading particle. In addition, the mean charged particle transverse momentum versus multiplicity is presented for the different event classes, and the sphericity distributions in bins of multiplicity are presented. The data are compared with calculations of standard Monte Carlo event generators. The transverse sphericity is found to grow with multiplicity at all collision energies, with a steeper rise at low $N_{\rm ch}$, whereas the event generators show the opposite tendency. The combined study of the sphericity and the mean $p_{\rm T}$ with multiplicity indicates that most of the tested event generators produce events with higher multiplicity by generating more back-to-back jets resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with tune PERUGIA-2011 exhibits a noticeable improvement in describing the data, compared to the other tested generators.Comment: 21 pages, 9 captioned figures, 3 tables, authors from page 16, published version, figures from http://aliceinfo.cern.ch/ArtSubmission/node/308

Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm{NN}}} = 2.76 TeV

The inclusive transverse momentum ($p_{\rm T}$) distributions of primary charged particles are measured in the pseudo-rapidity range $|\eta|<0.8$ as a function of event centrality in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}=2.76$ TeV with ALICE at the LHC. The data are presented in the $p_{\rm T}$ range $0.15<p_{\rm T}<50$ GeV/$c$ for nine centrality intervals from 70-80% to 0-5%. The Pb-Pb spectra are presented in terms of the nuclear modification factor $R_{\rm{AA}}$ using a pp reference spectrum measured at the same collision energy. We observe that the suppression of high-$p_{\rm T}$ particles strongly depends on event centrality. In central collisions (0-5%) the yield is most suppressed with $R_{\rm{AA}}\approx0.13$ at $p_{\rm T}=6$-7 GeV/$c$. Above $p_{\rm T}=7$ GeV/$c$, there is a significant rise in the nuclear modification factor, which reaches $R_{\rm{AA}} \approx0.4$ for $p_{\rm T}>30$ GeV/$c$. In peripheral collisions (70-80%), the suppression is weaker with $R_{\rm{AA}} \approx 0.7$ almost independently of $p_{\rm T}$. The measured nuclear modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/284