262,448 research outputs found
Meiotic double strand breaks repair in sexually reproducing eukaryotes: We are not all equal.
No full textThe defining event of meiosis is prophase-I, during which the maternal and paternal chromosome find each other in the nucleus, pair, and align in a process called “synapses of the homologues”. Their faithful segregation during the first meiotic division (MI) requires meiotic recombination and in particular at least one crossing over (CO) per pair of homologous chromosomes. COs are needed, not only to generate diversity within a population, but (along with sister chromatids cohesion) to form the chiasmata that are the physical connection between the homologues that ensures their faithful segregation at metaphase-I. Our understanding of recombination in higher eukaryotes has comes from studies in model organisms such as yeasts, flies and worms. Although there are clear differences among organisms, most of the genes and proteins that are required in these processes are conserved and have orthologues in mammals. However, their null mutations in mice (Mus musculus) do not always display the same phenotype as in lower eukaryotes, indicating that along with the increased complexity of the genome, same genes have acquired new or partially overlapping functions. In this review we will focus on the main genes and protein products which are required for meiotic recombination, comparing the simple metazoan C. elegans and the mouse, underlying divergences and similarities between these organism
On vowel prosthesis before sC in Substandard Latin and Koine Greek: a synoptic review
No full textThis paper aims at proposing a synoptic account of vowel prosthesis in word-initial sC in Substandard Latin and Koine Greek. A new recensio of the attestations in documentary texts suggests that the phenomenon was spread all around the Roman Empire, both in Substandard Latin and Koine Greek (§ 2). Different syntopic analyses have been subsequently provided in order to investigate both external and internal factors, namely to which level of variation this phenomenon is to be attributed in a diasystematic perspective and the phonotactic and prosodic contexts in which vowel prosthesis emerges (§§ 3, 4). Finally (§ 5), the diachronic path is taken into account focusing on the following topics: i. the relation between polygenesis and monogenesis, continuity and discontinuity; ii. Greek/Latin interference, in the attempt to establish which language is responsible for triggering the phenomenon; iii. phonological drifts in Substandard Latin which determined the creation of a word-initial pattern (viz. the deletion of initial ex-, the simplification of #in+sC into #isC and the aphaeresis of #VsC into #sC)
Impiego di insilati: rapporti con l'ambiente
No full textI dati sperimentali indicano che l'uso di polpa di bietola surpressata nella dieta determina una riduzione della quota di azoto escreta dagli animali per via urinaria, a tutto vantaggio della riduzione dell'impatto ambientale delle deiezioni zootecniche
Detailed imaging of tectonic structures by multiscale earth resistivity tomographies: the Colfiorito normal faults (Central Italy)
No full textThis study is aimed to show how cost effective geophysical surveying, integrated with detailed knowledge of the local geology, can give a significant contribution to image the subsurface structure of complex areas of active faulting. The combined inversion of a data set consisting of a large scale tomography and a target-dependent multiresolution dipole-dipole measurements, the multiscale approach, is shown to yield detailed structural information and to infer some characteristics of the fault zone. The operating procedure, applied to the Colfiorito fault system,
allowed to differentiate the electrical signatures of the crossed faults. Minor faults show sharp lateral variations generated by a contact between different geological formations, while the major faults are also characterized by a decrease in resistivity values distributed on the fault damage zones. A close interpretation was supported by detailed geological surface data. Besides, quantitative correlations between in situ resistivity distribution and geological units were supported by electrical logs
Le pieghe minori nelle Unità Imeresi e Trapanesi dei Monti di Palermo ed il loro significato nell’evoluzione tettonica dell’area
No full textIn questo lavoro sono riassunte le osservazioni sulle pieghe minori che interessano i terreni delle Unità Imeresi e Trapanesi del settore orientale dei Monti di Palermo, con l'obbiettivo di: a) descri-vere la geometria e lo stile deformativo delle mesopieghe e stabilirne le relazioni spazio-temporali con le pieghe maggiori e le altre strut-ture minori (clivaggi, joints); b) ricavare, attraverso l'analisi stati-stica dei dati giaciturali, l'orientazione dei campi deformativi asso-ciati alle strutture plicative; c) ricostruire il significato delle pieghe minori nell'evoluzione tettonica dell'area. Nelle Unità Imeresi e Trapanesi, l'analisi statistica dei dati e le osservazioni di campagna hanno permesso di riconoscere due generazioni di pieghe di origine tettonica (H 1 e H 2), che in tutta l'area si sovrappongono a pre-esistenti deformazioni gravitative (slumping). La generazione delle pieghe minori H 1, che mostrano orienta-zioni diverse nelle diverse unità tettoniche, appare precedente alla messa in posto delle unità tettoniche, che è stata accompagnata da rotazioni differenziali. La popolazione di pieghe minori più recente (H 2), che mostra una orientazione costante in tutta l'area, sarebbe invece in relazione con le fasi deformative successive alla messa in posto delle unità tettoniche. ABSTRACT Minor folds in the Imerese and Trapanese units of the Palermo Mts.: their implications for the tectonic evolution of the area
Lithological and structural controls on the seismogenesis of the Umbria region: observations from seismic reflection profiles
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Protecting Animals 36: Author Witi Ihimaera
No full textIn this very special episode of Knowing Animals I am joined by beloved New Zealand author Witi Ihimaera. Witi has written many books featuring nonhuman animals. He offers us a non-colonial lens through which to think about the human/nonhuman relationship
Alcune esperienze di valorizzazione del patrimonio ambientale e paesaggistico
No full textLo studio dei territori colpiti dagli eventi sismici ha messo in evidenza alcune esigenze strutturali che, se affrontate e trasformate in progettualità facendo leva sulle potenzialità del patrimonio ambientale e paesaggistico locale, potrebbero creare le condizioni per la rinascita socio-economica del Centro Italia
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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