635 research outputs found

    Short history of Biology from the origins to the 20th Century

    Get PDF
    The book tells the story of the development of both knowledge and theories about the living organisms since Antiquity until the beginning of the 20th century. It also endeavours to link the advances in sciences and the events in the life of scientists with the historical and social framework within which they lived. When possible some hints have been provided about the personalities of the scientists themselves. It is especially meant both for biologists and naturalists, but an attempt has been made to make it interesting reading also for any layman with an interest in history and sciences

    Stabilizzazione di movimenti franosi con ancoraggi flottanti: il caso di frana Val Maso (Valli del Pasubio, Vicenza)

    Get PDF
    La nota presenta una tecnica per la stabilizzazione di movimenti franosi denominata \u201cancoraggio flottante\u201d che \ue8 stata oggetto di studio e di sviluppo teorico e applicativo all\u2019interno di un Dottorato di Ricerca a tema. La tecnica prevede l\u2019installazione di ancoraggi passivi nel corpo di frana, cementati al terreno e con adeguata fondazione nel terreno stabile profondo, posizionati secondo una geometria discontinua senza una parete di rivestimento del versante, ma con la sola applicazione di una piastra di ridotte dimensioni collegata alla testa di ciascuna barra. Dopo una rapida presentazione della tecnica e di un semplice schema di dimensionamento, si presentano un\u2019applicazione per la sistemazione della frana di Val Maso (Valli del Pasubio, Vicenza) e i risultati di 18 mesi di monitoraggio post intervento

    Ergosterol reduction impairs mitochondrial DNA maintenance in S. cerevisiae

    Get PDF
    Sterols are essential lipids, involved in many biological processes. In Saccharomyces cerevisiae, the enzymes of the ergosterol biosynthetic pathway (Erg proteins) are localized in different cellular compartments. With the aim of studying organelle interactions, we discovered that Erg27p resides mainly in Lipid Droplets (LDs) in respiratory competent cells, while in absence of respiration, is found mostly in the ER. The results presented in this paper demonstrate an interplay between the mitochondrial respiration and ergosterol production: on the one hand, rho° cells show lower ergosterol content when compared with wild type respiratory competent cells, on the other hand, the ergosterol biosynthetic pathway influences the mitochondrial status, since treatment with ketoconazole, which blocks the ergosterol pathway, or the absence of the ERG27 gene, induced rho° production in S. cerevisiae. The loss of mitochondrial DNA in the ∆erg27 strain is fully suppressed by exogenous addition of ergosterol. These data suggest the notion that ergosterol is essential for maintaining the mitochondrial DNA attached to the inner mitochondrial membrane

    THE COINAGE OF THE SO-CALLED PARTHIAN “DARK AGE” REVISITED

    Get PDF
    THE COINAGE OF THE SO-CALLED PARTHIAN “DARK AGE” REVISITE

    Prevalence of Chlamydophila felis and feline herpesvirus 1 in cats with conjunctivitis in northern Italy.

    Get PDF
    The prevalence of Chlamydophila felis and feline herpesvirus 1 (FHV-1) infection in cats with conjunctivitis in northern Italy was investigated by conventional polymerase chain reaction (PCR) testing. In cats with conjunctivitis, C felis and FHV-1 were detected in 14 of 70 (20%) and in 23 of 70 (33%) animals, respectively. None of the 35 control cats were positive for C felis, whereas 7 (20%) of these cats were positive for FHV-1. Mixed infections were present in 5 of 70 cats (7%). Cats positive for C felis were significantly younger than control animals (P = .02), whereas no significant age differences were observed between FHV-1-positive cats and control cats (P = .41) or between FHV-1-positive animals and C felis-positive animals (P = .16). Cats sampled during acute-phase conjunctivitis were also investigated for the presence of C felis by conjunctival scrapings. In this acute phase, substantial agreement was found when comparing the results of the 2 methods (K = .80). The association between PCR results and conjunctivitis was evaluated for the 2 pathogens. The presence of C felis was significantly associated with conjunctivitis (P = .004), whereas the detection of FHV-1 did not significantly correlate with the clinical sign (P = .25), suggesting that, by itself. PCR is not suitable for the diagnosis of FHV-1-related conjunctivitis

    Floppy eyelid, an under-diagnosed syndrome: a review of demographics, pathogenesis, and treatment

    Get PDF
    Floppy eyelid syndrome (FES) is a frequent eyelid disorder characterized by eyelid laxity that determines a spontaneous eyelid eversion during sleep associated with chronic papillary conjunctivitis and systemic diseases. FES is an under-diagnosed syndrome for the inaccuracy of definition and the lack of diagnostic criteria. Eyelid laxity can result from a number of involutional, local, and systemic diseases. Thus, it is pivotal to use the right terminology. When the increased distractibility of the upper or lower eyelid is an isolated condition, it is defined as 'lax eyelid condition' (LAC). When laxity is associated with ocular surface disorder such as papillary conjunctivitis and dry eyes, it can be referred to as 'lax eyelid syndrome' (LES). However, FES is characterized by the finding of a very loose upper eyelid which everts very easily and papillary tarsal conjunctivitis affecting a specific population of patients, typically male, of middle age and overweight. Obesity in middle-aged male is also recognized as the strongest risk factor in obstructive sleep apnea-hypopnea syndrome, (OSAHS). FES has been reported as the most frequent ocular disorder associated with OSAHS. Patients with FES often complain of non-pathognomonic ocular signs and symptoms such as pain, foreign body sensation, redness, photophobia, and lacrimation. Due to these clinical features, FES is often misdiagnosed while an early recognition might be important to avoid its chronic, distressing course and the associated morbidities. This review provides an updated overview on FES by describing the epidemiology, proposed pathogenesis, clinical manifestations, related ocular, and systemic diseases, and treatment options

    Pyrosequencing analysis of fungal assemblages from geographically distant, disparate soils reveals spatial patterning and a core mycobiome

    Get PDF
    Identifying a soil core microbiome is crucial to appreciate the established microbial consortium, which is not usually subjected to change and, hence, possibly resistant/resilient to disturbances and a varying soil context. Fungi are a major part of soil biodiversity, yet the mechanisms driving their large-scale ecological ranges and distribution are poorly understood. The degree of fungal community overlap among 16 soil samples from distinct ecosystems and distant geographic localities (truffle grounds, a Mediterranean agro-silvo-pastoral system, serpentine substrates and a contaminated industrial area) was assessed by examining the distribution of fungal ITS1 and ITS2 sequences in a dataset of 454 libraries. ITS1 and ITS2 sequences were assigned to 1,660 and 1,393 Operational Taxonomic Units (OTUs; as defined by 97% sequence similarity), respectively. Fungal beta-diversity was found to be spatially autocorrelated. At the level of individual OTUs, eight ITS1 and seven ITS2 OTUs were found in all soil sample groups. These ubiquitous taxa comprised generalist fungi with oligotrophic and chitinolytic abilities, suggesting that a stable core of fungi across the complex soil fungal assemblages is either endowed with the capacity of sustained development in the nutrient-poor soil conditions or with the ability to exploit organic resources (such as chitin) universally distributed in soils
    corecore