Search results for "RICH"
showing 10 items of 3360 documents
Transmembrane signaling in the sensor kinase DcuS of Escherichia coli : A long-range piston-type displacement of transmembrane helix 2
2015
The C4-dicarboxylate sensor kinase DcuS is membrane integral because of the transmembrane (TM) helices TM1 and TM2. Fumarate-induced movement of the helices was probed in vivo by Cys accessibility scanning at the membrane-water interfaces after activation of DcuS by fumarate at the periplasmic binding site. TM1 was inserted with amino acid residues 21-41 in the membrane in both the fumarate-activated (ON) and inactive (OFF) states. In contrast, TM2 was inserted with residues 181-201 in the OFF state and residues 185-205 in the ON state. Replacement of Trp 185 by an Arg residue caused displacement of TM2 toward the outside of the membrane and a concomitant induction of the ON state. Results …
Inferring the Relative Resilience of Alternative States
2013
Ecological systems may occur in alternative states that differ in ecological structures, functions and processes. Resilience is the measure of disturbance an ecological system can absorb before changing states. However, how the intrinsic structures and processes of systems that characterize their states affects their resilience remains unclear. We analyzed time series of phytoplankton communities at three sites in a floodplain in central Spain to assess the dominant frequencies or "temporal scales" in community dynamics and compared the patterns between a wet and a dry alternative state. The identified frequencies and cross-scale structures are expected to arise from positive feedbacks that…
Impact of Trichoderma sp. on the Development of Heterobasidion Annosum in Decayed Understory Picea Abies Stumps
2017
Abstract Heterobasidion annosum (Fr.) Bref. s.l. causes significant economic losses in conifer forests. Therefore, to reduce the spread of the infection surfaces of freshly cut conifer, stumps are commonly treated with biological control agents. Trichoderma sp. shows very strong antagonistic effect against H. annosum in vitro, but relatively few field studies have been conducted. Moreover, most of previous studies examined the impact of Trichoderma sp. on H. annosum in healthy conifer stumps. The aim of our work was to evaluate the effect of Trichoderma sp. against H. annosum in already decayed understory spruce stumps. In total, 75 decayed spruce stumps were surveyed. Part of the spruce st…
Biodiversidad en el Siglo XXI: más allá del conteo de especies
2018
In modern ecology, the traditional diversity indexes (usually of richness, abundance, and species evenness) have been highly revealing and useful for monitoring community and ecosystem processes. However, around two decades ago, a pioneering research team noticed that these indexes did not completely resolve their open questions. Thus, they suggested changing the way biodiversity was measured. At its base, this new methodology considers the distance between species (in phylogenetic or functional terms) before subsequently applying the appropriate biodiversity indexes. Including phylogenetic and functional elements in the evaluation of diversity allows us to approach the concept of biodivers…
A multivariate approach to the study of orichalcum ingots from the underwater Gela's archaeological site
2017
Abstract In this work a careful ICP-OES and ICP-MS investigation of 38 ancient ingots has been performed to determine both major components and trace elements content to find a correlation between the observed different features and the composition. The ingots, recovered in an underwater archaeological site of various finds near Gela (CL, Italy), were previously investigated by X-Ray Fluorescence (XRF) spectroscopy to know the composition of the alloy and it was found that the major elements were copper and zinc, in a ratio compatible with the famous orichalcum similar to the contemporary brass that was considered a precious metal in ancient times. The discovery of huge amount this alloy is…
Major Histocompatibility Complex Class I Allele-specific Cooperative and Competitive Interactions between Immune Evasion Proteins of Cytomegalovirus
2002
Cytomegaloviruses (CMVs) deploy a set of genes for interference with antigen presentation in the major histocompatibility complex (MHC) class I pathway. In murine CMV (MCMV), three genes were identified so far: m04/gp34, m06/gp48, and m152/gp40. While their function as immunoevasins was originally defined after their selective expression, this may not necessarily reflect their biological role during infection. The three immunoevasins might act synergistically, but they might also compete for their common substrate, the MHC class I complexes. To approach this question in a systematic manner, we have generated a complete set of mutant viruses with deletions of the three genes in all seven pos…
Sentieri interrotti. Musicisti europei nel crepuscolo dell'Occidente
2012
Il volume descrive il contesto in cui vedono la luce le due mostre dedicate all’Arte Degenerata (Monaco 1937) e alla Musica Degenerata (Düsseldorf 1938), soffermandosi in modo particolare sui percorsi biografici e artistici di quattro compositori la cui biografia venne sconvolta dalla politica culturale nazista: Franz Schreker, Alexander Zemlinsky, Erich Wolfgang Korngold e Viktor Ullmann. Si tratta di autori di origine ebraica, legati in vario modo alla vita musicale di città come Berlino, Vienna e Praga, assai diversi per formazione e linguaggio, ma tutti travolti da una serie di eventi (l'avvento al potere di Hitler, la guerra, la Shoah) che trasformarono i loro percorsi biografici in al…
Esuberanza e mistero
2011
Il testo è stato realizzato in occasione di un'esecuzione della Sinfonia n. 8 in sol maggiore op. 88 di Antonìn Dvoràk e di due brani vocali di Johannes Brahms: "Schicksalslied" per coro e orchestra op. 54 e "Naenie" per coro e orchestra op. 82. In particolare, per quanto riguarda le opere di Brahms, viene analizzato il contesto biografico in cui vedono la luce e il rapporto fra la struttura musicale e i testi poetici di Hoelderlin e di Schiller.
I titani della "Décadence". Su Friedrich Nietzsche e Richard Wagner
2016
Il saggio traccia un quadro dei rapporti fra Nietzsche e Wagner, dal primo incontro nel 1869 sino alla definitiva "rottura" nei giorni dell'inaugurazione del Festspielhaus di Bayreuth e della prima rappresentazione di "Parsifal". Particolare attenzione viene riservata all'opera per pianoforte a 4 mani "Nachklang Heiner Sylvesternacht", scritta da Nietzsche nel novembre 1871 e dedicata a Cosima Wagner.
Correlation between mutation rate and genome size in riboviruses: mutation rate of bacteriophage Qβ.
2013
Abstract Genome sizes and mutation rates covary across all domains of life. In unicellular organisms and DNA viruses, they show an inverse relationship known as Drake’s rule. However, it is still unclear whether a similar relationship exists between genome sizes and mutation rates in RNA genomes. Coronaviruses, the RNA viruses with the largest genomes (∼30 kb), encode a proofreading 3′ exonuclease that allows them to increase replication fidelity. However, it is unknown whether, conversely, the RNA viruses with the smallest genomes tend to show particularly high mutation rates. To test this, we measured the mutation rate of bacteriophage Qβ, a 4.2-kb levivirus. Amber reversion-based Luria–D…