212 research outputs found

    The Genetic Architecture of Adaptation to Leaf and Root Bacterial Microbiota in Arabidopsis thaliana

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    Understanding the role of the host genome in modulating microbiota variation is a need to shed light on the holobiont theory and overcome the current limits on the description of host-microbiota interactions at the genomic and molecular levels. However, the host genetic architecture structuring microbiota is only partly described in plants. In addition, most association genetic studies on microbiota are often carried out outside the native habitats where the host evolves and the identification of signatures of local adaptation on the candidate genes has been overlooked. To fill these gaps and dissect the genetic architecture driving adaptive plant-microbiota interactions, we adopted a genome-environment association (GEA) analysis on 141 whole-genome sequenced natural populations of Arabidopsis thaliana characterized in situ for their leaf and root bacterial communities in fall and spring, and a large range of nonmicrobial ecological factors (i.e., climate, soil, and plant communities). A much higher fraction of among-population microbiota variance was explained by the host genetics than by nonmicrobial ecological factors. Importantly, the relative importance of host genetics and nonmicrobial ecological factors in explaining the presence of particular operational taxonomic units (OTUs) differs between bacterial families and genera. In addition, the polygenic architecture of adaptation to bacterial communities was highly flexible between plant compartments and seasons. Relatedly, signatures of local adaptation were stronger on quantitative trait loci (QTLs) of the root microbiota in spring. Finally, plant immunity appears as a major source of adaptive genetic variation structuring bacterial assemblages in A. thaliana

    On Sigma-Protocols and (packed) Black-Box Secret Sharing Schemes

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    Σ\Sigma-protocols are a widely utilized, relatively simple and well understood type of zero-knowledge proofs. However, the well known Schnorr Σ\Sigma-protocol for proving knowledge of discrete logarithm in a cyclic group of known prime order, and similar protocols working over this type of groups, are hard to generalize to dealing with other groups. In particular with hidden order groups, due to the inability of the knowledge extractor to invert elements modulo the order. In this paper, we introduce a universal construction of Σ\Sigma-protocols designed to prove knowledge of preimages of group homomorphisms for any abelian finite group. In order to do this, we first establish a general construction of a Σ\Sigma-protocol for R\mathfrak{R}-module homomorphism given only a linear secret sharing scheme over the ring R\mathfrak{R}, where zero knowledge and special soundness can be related to the privacy and reconstruction properties of the secret sharing scheme. Then, we introduce a new construction of 2-out-of-nn packed black-box secret sharing scheme capable of sharing kk elements of an arbitrary (abelian, finite) group where each share consists of k+logn3k+\log n-3 group elements. From these two elements we obtain a generic ``batch\u27\u27 Σ\Sigma-protocol for proving knowledge of kk preimages of elements via the same group homomorphism, which communicates k+λ3k+\lambda-3 elements of the group to achieve 2λ2^{-\lambda} knowledge error. For the case of class groups, we show that our Σ\Sigma-protocol improves in several aspects on existing proofs for knowledge of discrete logarithm and other related statements that have been used in a number of works. Finally, we extend our constructions from group homomorphisms to the case of ZK-ready functions, introduced by Cramer and Damg\aa rd in Crypto 09, which in particular include the case of proofs of knowledge of plaintext (and randomness) for some linearly homomorphic encryption schemes such as Joye-Libert encryption. However, in the case of Joye-Libert, we show an even better alternative, using Shamir secret sharing over Galois rings, which achieves 2k2^{-k} knowledge soundness by communicating kk ciphertexts to prove kk statements

    multitemporal analysis of algal blooms with meris images in a deep meromictic lake

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    MERIS images (2003-2011) were used to detect algal bloom events in Lake Idro (Northern Italy) applying a semi-empirical algorithm. From the study of an intense phenomenon occurred in late summer 2010, a retrospective analysis of similar events during late summer/ early autumn period was performed. High intra- and inter-annual variability was observed and three additional bloom events were identified on 2003, 2005 and 2008. Hydrological and weather parameters were examined at different temporal intervals (August-October, September-October and monthly from August to October) to investigate the regulating factors of bloom incidence. Rather low temperatures and the persistence of clouds seem t

    Phosphate binding by a novel Zn(II) complex featuring a trans-1,2-diaminocyclohexane ligand. Effective anion recognition in water

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    Excellent affinities and selectivities toward triphosphates are achieved through an adaptive ditopic receptor featuring a metal ion and a macrocyclic polyammonium cation binding sites, concertedly bridging phosphate anions

    Los discursos de odio como discursos sociales : Modelo teórico y metodológico en un corpus de estudio sobre construcciones mediáticas

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    Material pedagógico-complementario que tiene como propósito dar cuenta de un modelo teórico y metodológico para indagar sobre las diversas modalidades que adquiere el discurso del odio (en adelante DDO), en la esfera pública digital, en la construcción y/o producción de subjetividad contemporánea.Facultad de Psicologí

    Signaling through Ras is essential for ret oncogene-induced cell differentiation in PC12 cells.

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    Specific germline mutations of the receptor tyrosine kinase, Ret, predispose to multiple endocrine neoplasia types 2A and 2B and familial medullary thyroid carcinoma. The mechanisms by which different Ret isoforms (Ret-2A and Ret-2B) cause distinct neoplastic diseases remain largely unknown. On the other hand, forced expression of these mutated versions of Ret induces the rat pheochromocytoma cell line, PC12, to differentiate. Here we used an inducible vector encoding a dominant-negative Ras (Ras p21(N17)) to investigate the contributions of the Ras pathway to the phenotype induced in PC12 cells by the expression of either Ret-2A or Ret-2B mutants. We show that the Ret-induced molecular and morphological changes are both mediated by Ras-dependent pathways. However, even though inhibition of Ras activity was sufficient to revert Ret-induced differentiation, the kinetics of morphological reversion of the Ret-2B- was more rapid than the Ret-2A- transfected cells. Further, we show that in Ret-transfected cells the suc1- associated neurotrophic factor-induced tyrosine phosphorylation target, SNT, is chronically phosphorylated in tyrosine residues, and associates with the Sos substrate. These results indicate the activation of the Ras cascade as an essential pathway triggered by the chronic active Ret mutants in PC12 cells. Moreover, our data indicate SNT as a substrate for both Ret mutants, which might mediate the activation of this cascade

    O055. Headache and psychopathological aspects in Gilles de la Tourette Sindrome:a comparison between paediatric and adult patients

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    Only few studies have analyzed the occurrence of headache in patients with Gilles de la Tourette syndrome (GTS) [1–3]. The aim of this study was to compare the prevalence and characteristics of headache in paediatric and adult patients with GTS and the relationship of headache with tic severity, psychiatric comorbidities and quality of life

    Adiponectin, diabetes and ischemic heart failure: a challenging relationship

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    Abstract Background Several peptides, named adipokines, are produced by the adipose tissue. Among those, adiponectin (AD) is the most abundant. AD promotes peripheral insulin sensitivity, inhibits liver gluconeogenesis and displays anti-atherogenic and anti-inflammatory properties. Lower levels of AD are related to a higher risk of myocardial infarction and a worse prognosis in patients with coronary artery disease. However, despite a favorable clinical profile, AD increases in relation to worsening heart failure (HF); in this context, higher adiponectinemia is reliably related to poor prognosis. There is still little knowledge about how certain metabolic conditions, such as diabetes mellitus, modulate the relationship between AD and HF. We evaluated the level of adiponectin in patients with ischemic HF, with and without type 2 diabetes, to elucidate whether the metabolic syndrome was able to influence the relationship between AD and HF. Results We demonstrated that AD rises in patients with advanced HF, but to a lesser extent in diabetics than in non-diabetics. Diabetic patients with reduced systolic performance orchestrated a slower rise of AD which began only in face of overt HF. The different behavior of AD in the presence of diabetes was not entirely explained by differences in body mass index. In addition, NT-proBNP, the second strongest predictor of AD, did not differ significantly between diabetic and non-diabetic patients. These data indicate that some other mechanisms are involved in the regulation of AD in patients with type 2 diabetes and coronary artery disease. Conclusions AD rises across chronic heart failure stages but this phenomenon is less evident in type 2 diabetic patients. In the presence of diabetes, the progressive increase of AD in relation to the severity of LV dysfunction is hampered and becomes evident only in overt HF.</p
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