Search results for "Bion"

Anti-plant Defense Response Strategies Mediated by the Secondary Symbiont

2019

Bacterial symbionts are omnipresent in insects, particularly aphids, and often exert important effects on the host ecology; however, examples of symbionts that mediate herbivore-plant interactions remain limited. Here, three clones with identical genetic backgrounds were established: a Hamiltonella defensa-free clone, H. defensa-infected clone and H. defensa-cured clone. H. defensa infection was found to increase the fitness of Sitobion miscanthi by increasing the total number of offspring and decreasing the age of first reproduction. Furthermore, gene expression studies and phytohormone measurement showed that feeding by the Hamiltonella-infected clone suppressed the salicylic acid (SA)- a…

Biodiversity Patterns and Ecological Preferences of the Photobionts Associated With the Lichen-Forming Genus Parmelia

2021

The worldwide, ecologically relevant lichen-forming genusParmeliacurrently includes 41 accepted species, of which theParmelia sulcatagroup (PSULgp) and theParmelia saxatilisgroup (PSAXgp) have received considerable attention over recent decades; however, phycobiont diversity is poorly known inParmelias. lat. Here, we studied the diversity ofTrebouxiamicroalgae associated with 159 thalli collected from 30 locations, including nineParmeliaspp.:P. barrenoae, P. encryptata, P. ernstiae, P. mayi, P. omphalodes, P. saxatilis, P. serrana, P. submontana, andP. sulcata. The mycobionts were studied by carrying out phylogenetic analyses of the nrITS. Microalgae genetic diversity was examined by using …

The Root Mycobiota of Betula aetnensis Raf., an Endemic Tree Species Colonizing the Lavas of Mt. Etna (Italy)

2021

Betula aetnensis is an endemic tree of high conservation value, which thrives on the nutrient-poor volcanic soils of Mount Etna. Since plant–microbe interactions could play a crucial role in plant growth, resource uptake, and resistance to abiotic stresses, we aimed to characterize the root and rhizosphere microbial communities. Individuals from natural habitat (NAT) and forest nursery (NURS) were surveyed through microscopy observations and molecular tools: bacterial and fungal automated ribosomal intergenic spacer analysis (ARISA), fungal denaturing gradient gel electrophoresis (DGGE). B. aetnensis was found to be simultaneously colonized by arbuscular (AM), ectomycorrhizal (ECM), ericoid…

BPS Dionu BIoni, Neekstremālie atrisinājumi AdS_5 × S^5 telpā un AdS/CFT duāli objekti

2019

Dotajā darbā tiek meklēti neekstremālie atrisinājumi, kuri atbilst Dionu BIoniem vai citiem solitonu tipa atrisinājumiem. Kā zināms Dž. Švarca \cite{Schwarz:2014zsa}, H. Maldasena \cite{Maldacena:1998im} un R. Maijersa \cite{Myers:1999ps} darbos tiek analizēti dažādi ekstremālie atrisinājumi, dotajā darbā sākumā tiek analizēta D3 zondes brānas ekstremālā konstrukcija $ AdS_{5} \times S^{5} $ telpā. Nākamajā posma šī ģeometrija tiek deformēta ieviešot metrikā melnos faktorus, kas arī attīsta notikuma horizonta jēdzienu (melnā brāna) un noved pie problēmas galīgo temperatūras atrisinājumu eksistenci un to interpretācijas. Ekstremālajā gadījumā ($ T = 0 $) tiek dots neatkarīgs jauns izvedums, …

Comparative Genomics of Blattabacterium cuenoti: The Frozen Legacy of an Ancient Endosymbiont Genome

2013

Many insect species have established long-term symbiotic relationships with intracellular bacteria. Symbiosis with bacteria has provided insects with novel ecological capabilities, which have allowed them colonize previously unexplored niches. Despite its importance to the understanding of the emergence of biological complexity, the evolution of symbiotic relationships remains hitherto a mystery in evolutionary biology. In this study, we contribute to the investigation of the evolutionary leaps enabled by mutualistic symbioses by sequencing the genome of Blattabacterium cuenoti, primary endosymbiont of the omnivorous cockroach Blatta orientalis, and one of the most ancient symbiotic associa…

Genome Evolution in the Primary Endosymbiont of Whiteflies Sheds Light on Their Divergence

2015

International audience; Hemipteran insects are well-known in their ability to establish symbiotic relationships with bacteria. Among them, heteropteran insects present an array of symbiotic systems, ranging from the most common gut crypt symbiosis to the more restricted bacteriome-associated endosymbiosis, which have only been detected in members of the superfamily Lygaeoidea and the family Cimicidae so far. Genomic data of heteropteran endosymbionts are scarce and have merely been analyzed from the Wolbachia endosymbiont in bed bug and a few gut crypt-associated symbionts in pentatomoid bugs. In this study, we present the first detailed genomic analysis of a bacteriome-associated endosymbi…

Morphological determination of the phototrophic community composition of biological soil crusts in coastal sand dunes in northern Germany

2022

This dataset comprises the microbial community composition of biological soil crusts in north-German sand dunes. For this we obtained enrichment cultures of phototrophic microorganisms, by placing fragments of biocrusts of the same Petri dishes as used for sequencing, in Petri dishes with Bold Basal (1N BBM) agarized medium (Bischoff and Bold 1963). Cultures were grown under standard laboratory conditions: with a 12-hour alteration of light and dark phases and irradiation of 25 μmol photons m-2 s-1 at a temperature 20 ± 5 ºС. Microscopic study of these raw cultures began in the third week of cultivation. Morphological examinations were performed using Olympus BX53 light microscope with Noma…

STRATEGIE DI DIREZIONAMENTO ALL’EPATOCARCINOMA DI FARMACI ANTITUMORALI MEDIANTE SISTEMI NANOPARTICELLARI E DI VISUALIZZAZIONE IN CELLULE TUMORALI DEL…

Lo scopo di questo lavoro di tesi è stato quello di realizzare nuovi sistemi nanoparticellari per il direzionamento di farmaci o di agenti per l’imaging, potenzialmente utilizzabili per la terapia e/o per la diagnosi dell’epatocarcinoma (HCC), in particolare per quelle forme caratterizzate dall’overespressione del recettore di membrana degli epatociti ASGP-R o del recettore mitocondriale TSPO. In particolare, nel capitolo 2 sono state descritte la sintesi, la caratterizzazione chimico fisica, la capacità di internalizzazione cellulare e l’efficacia antitumorale di un nuovo sistema nanoparticellare, costituito da un dendrimero a struttura poli-amido-aminica (PAMAM) di quarta generazione, opp…

Effect of Morphology and Size of Halloysite Nanotubes on Functional Pectin Bionanocomposites for Food Packaging Applications

2017

Pectin bionanocomposite films filled with various concentrations of two different types of halloysite nanotubes were prepared and characterized in this study as potential films for food packaging applications. The two types of halloysite nanotubes were long and thin (patch) (200-30 000 nm length) and short and stubby (Matauri Bay) (50-3000 nm length) with different morphological, physical, and dispersibility properties. Both matrix (pectin) and reinforcer (halloysite nanotubes) used in this study are considered as biocompatible, natural, and low-cost materials. Various characterization tests including Fourier transform infrared spectroscopy, field emission scanning electron microscopy, rele…

On the interpretation of optical illusions.

1973

If excited by stimuli adjacent in space and time, the optical system frequently perceives illusions in the form of apparent movements. These effects may be attributed to the dynamic properties of the retinal nerve nets. On the basis of a specific psychophysical experiment the mechanism underlying the generation of optical illusions is interpreted by the methods of systems theory and its use in systems analysis is discussed. It is shown that for the perception of apparent movements the transit times of the signals in the dendrites are particularly important.