Self-DNA Early Exposure in Cultivated and Weedy Setaria Triggers ROS Degradation Signaling Pathways and Root Growth Inhibition

The accumulation of fragmented extracellular DNA reduces conspecific seed germination and plantlet growth in a concentration-dependent manner. This self-DNA inhibition was repeatedly reported, but the underlying mechanisms are not fully clarified. We investigated the species-specificity of self-DNA inhibition in cultivated vs. weed congeneric species (respectively, Setaria italica and S. pumila) and carried out a targeted real-time qPCR analysis under the hypothesis that self-DNA elicits molecular pathways that are responsive to abiotic stressors. The results of a cross-factorial experiment on root elongation of seedlings exposed to self-DNA, congeneric DNA, and heterospecific DNA from Brassica napus and Salmon salar confirmed a significantly higher inhibition by self-DNA as compared to non-self-treatments, with the latter showing a magnitude of the effect consistent with the phylogenetic distance between the DNA source and the target species. Targeted gene expression analysis highlighted an early activation of genes involved in ROS degradation and management (FSD2, ALDH22A1, CSD3, MPK17), as well as deactivation of scaffolding molecules acting as negative regulators of stress signaling pathways (WD40-155). While being the first exploration of early response to self-DNA inhibition at molecular level on C4 model plants, our study highlights the need for further investigation of the relationships between DNA exposure and stress signaling pathways by discussing potential applications for species-specific weed control in agriculture

Flood susceptibility assessment in a highly urbanized alluvial fan: the case study of Sala Consilina (southern Italy)

Abstract. This paper deals with the risk assessment to alluvial fan flooding at the piedmont zone of carbonate massifs of the southern Apennines chain (southern Italy). These areas are prime spots for urban development and are generally considered to be safer than the valley floors. As a result, villages and towns have been built on alluvial fans which, during intense storms, may be affected by flooding and/or debris flow processes. The study area is located at the foothills of the Maddalena mountains, an elongated NW-SE trending ridge which bounds to the east the wide intermontane basin of Vallo di Diano. The area comprises a wide detrital talus (bajada) made up by coalescent alluvial fans, ranging in age from the Middle Pleistocene to the Holocene. Historical analysis was carried out to ascertain the state of activity of the fans and to identify and map the zones most hit by past flooding. According to the information gathered, the Sala Consilina fans would appear prone to debris flows; in the past these processes have produced extensive damage and loss of life in the urban area. The watershed basins feeding the fans have very low response times and may produce debris flow events with high magnitudes. Taking into account the historical damage, the fan surface morphology, and the present urban development (street orientation and hydraulic network), the piedmont area was zoned and various susceptibility classes were detected. These results may represent a useful tool for studies aiming at territorial hazard mapping and civil protection interventions

Contextual Lumpability

Quantitative analysis of computer systems is often based on Markovian models. Among the formalisms that are used in practice, Markovian process algebras have found many applications, also thanks to their compositional nature that allows one to specify systems as interacting individual automata that carry out actions. Nevertheless, as with all state-based modelling techniques, Markovian process algebras suffer from the well-known state space explosion problem. State aggregation, specifically lumping, is one of the possible methods for tackling this problem. In this paper we revisit the notion of Markovian bisimulation which has previously been shown to induce a lumpable relation in the underlying Markov process. Here we consider the coarser relation of contextual lumpability, and taking the specific example of strong equivalence in PEPA, we propose a slightly relaxed definition of Markovian bisimulation, named lumpable bisimilarity, and prove that this is a characterisation of the notion of contextual lumpability for PEPA components. Moreover, we show that lumpable bisimilarity induces the largest contextual lumping over the Markov process underlying any PEPA component. We provide an algorithm for lumpable bisimilarity and study both its time and space complexity. 1

Arabidopsis thaliana response to extracellular dna: Self versus nonself exposure

The inhibitory effect of extracellular DNA (exDNA) on the growth of conspecific individuals was demonstrated in different kingdoms. In plants, the inhibition has been observed on root growth and seed germination, demonstrating its role in plant\u2013soil negative feedback. Several hypotheses have been proposed to explain the early response to exDNA and the inhibitory effect of conspecific exDNA. We here contribute with a whole-plant transcriptome profiling in the model species Arabidopsis thaliana exposed to extracellular self-(conspecific) and nonself-(heterologous) DNA. The results highlight that cells distinguish self-from nonself-DNA. Moreover, confocal microscopy analyses reveal that nonself-DNA enters root tissues and cells, while self-DNA remains outside. Specifically, exposure to self-DNA limits cell permeability, affecting chloroplast functioning and reactive oxygen species (ROS) production, eventually causing cell cycle arrest, consistently with macroscopic observations of root apex necrosis, increased root hair density and leaf chlorosis. In contrast, nonself-DNA enters the cells triggering the activation of a hypersensitive response and evolving into systemic acquired resistance. Complex and different cascades of events emerge from exposure to extracellular selfor nonself-DNA and are discussed in the context of Damage-and Pathogen-Associated Molecular Patterns (DAMP and PAMP, respectively) responses

Colloquial Arabic Teaching at Ca' Foscari

Since the '70s Ca' Foscari teachers have been facing the challenge of diglossia that typifies the Arab world where the oral use of Standard Arabic is reserved to specific situations, while colloquial varieties of the same language are used for ordinary conversations. Thus, learning Colloquial Arabic is a paramount need to communicate with native Arabic speakers. Moreover, diglottic proficiency is necessary to access several contemporary cultural outputs of the Arab world. This article describes the features of Arabic diglossia and instructional approaches meant to cope with the phenomenon. It then offers a brief account of Colloquial Arabic teaching at Ca' Foscari, which has been a European vanguard in the field

N uptake, assimilation and isotopic fractioning control \u3b4 15N dynamics in plant DNA: A heavy labelling experiment on Brassica napus L

In last decades, a large body of evidence clarified nitrogen isotope composition (\u3b415N) patterns in plant leaves, roots and metabolites, showing isotopic fractionation along N uptake and assimilation pathways, in relation to N source and use efficiency, also suggesting 15N depletion in plant DNA. Here we present a manipulative experiment on Brassica napus var. oleracea, where we monitored \u3b4 15N of purified, lyophilized DNA and source leaf and root materials, over a 60-days growth period starting at d 60 after germination, in plants initially supplied with a heavy labelled (\u3b4 15NAir-N2 = 2100 mUr) ammonium nitrate solution covering nutrient requirements for the whole observation period (470 mg N per plant) and controlling for the labelled N species (N H4, N O3 and both). Dynamics of Isotopic Ratio Mass Spectrometry (IRMS) data for the three treatments showed that: (1) leaf and root \u3b4 15N dynamics strictly depend on the labelled chemical species, with N H4, N O3 and N H4N O3 plants initially showing higher, lower and intermediate values, respectively, then converging due to the progressive NH4+ depletion from the nutrient solution; (2) in N H4N O3, where \u3b415N was not affected by the labelled chemical species, we did not observe isotopic fractionation associated to inorganic N uptake; (3) \u3b415N values in roots compared to leaves did not fully support patterns predicted by differences in assimilation rates of NH4+ and NO3-; (4) DNA is depleted in 15N compared to the total N pools of roots and leaves, likely due to enzymatic discrimination during purine biosynthesis. In conclusion, while our experimental setup did not allow to assess the fractionation coefficient (\u3b5) associated to DNA bases biosynthesis, this is the first study specifically reporting on dynamics of specific plant molecular pools such as nucleic acids over a long observation period with a heavy labelling technique

The spread of the non-native pine tortoise scale toumeyella parvicornis (Hemiptera: Coccidae) in europe: A major threat to pinus pinea in southern Italy

Invasive pests are considered a major threat to biodiversity, conservation and agriculture. The Italian peninsula is a major site of intensive commercial exchange and transport of plants and goods, being consequently one of the European countries most invaded by alien insects. Hemiptera Coccomorpha are the largest group of non-native species recorded in Europe. For example, in the last 70 years more than 50 scale insect species have been accidentally introduced into Italy, 50% of which are now well established. This study was conducted to investigate the biology and the damage of the non-native pine tortoise scale Toumeyella parvicornis Cockerell (Hemiptera: Coccidae) accidentally introduced a few years ago into southern Italy. T. parvicornis is multivol-tine in the invaded territories, being able to complete at least three generations per year, overwintering in the adult female stage. Oviposition periods during 2015-2017 surveys occurred from late April to end of May, from July to first half of August, and from mid-September to November. Fecundity was positively correlated to body size of gravid females and varied among the generations. Investigations on natural control by autochthonous species showed a seasonal activity of Metaphycus flavus (Hymenoptera: Encyrtidae), parasitizing mainly immature male individuals. The morpho-molecular approach confirms the hypothesis of an ongoing shift of parasitoid populations from other indigenous soft scales to the invasive one. Unfortunately, the low level of natural control was ineffective in hampering the spread of T. parvicornis, and preventing the dieback of local pine species, Pinus pinea, as observed in all invaded areas

Bollettino di Ca' Foscari n. 1 - 1968. Associazione "Primo Lanzoni" tra gli antichi studenti di Ca' Foscari Venezia

Il Bollettino n. 1 del 1968, il primo dell'ultima serie del periodico, dopo una premessa del presidente dell'Associazione, Giampiero Franco, sulle modifiche apportate dal Consiglio allo Statuto della Facoltà di Economia e Commercio, entra nel dettaglio delle riforme, riportando il programma dei vari dipartimenti ed i pareri più o meno favorevoli di docenti e studenti a tali riforme. Continua l'abituale ripartizione interna del Bollettino con le rubriche dedicate alla vita di Ca' Foscari, in cui si dà notizia della riconferma di Italo Siciliano a rettore dell'Ateneo e del DPR del 28 maggio 1968 che sancisce il mutamento dello status giuridico di Ca' Foscari da "Istituto Universitario" a "Università degli Studi", e quelle sulla vita dell'Associazione. Il Bollettino si chiude con una nuova rubrica dal titolo "Lettere al Direttore" e con le segnalazioni librarie. PER RICERCHE SUL TESTO INTEGRALE, EFFETTUARE IL DOWNLOAD DEL LIBRO

Retrieving Consistent Multimedia Presentation Fragments

In this paper we discuss some issues about information retrieval in multimedia presentations. We introduce a class of multimedia presentations made of independent and synchronized media, and discuss retrieval requirements of presentation fragments. Then we discuss a retrieval model able to reconstruct the fragments of a presentation from the atomic components returned by the execution of queries to multimedia presentation repositories. The retrieval model is based on an automaton which formally describes the presentation states entered by the events which trigger media playback. Retrieving a consistent fragment corresponds to building a new presentation with all the media related to the retrieved ones, with their original structural and synchronization relationships