1,085 research outputs found

    Preconditioning of the background error covariance matrix in data assimilation for the Caspian Sea

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    Data Assimilation (DA) is an uncertainty quantification technique used for improving numerical forecasted results by incorporating observed data into prediction models. As a crucial point into DA models is the ill conditioning of the covariance matrices involved, it is mandatory to introduce, in a DA software, preconditioning methods. Here we present first studies concerning the introduction of two different preconditioning methods in a DA software we are developing (we named S3DVAR) which implements a Scalable Three Dimensional Variational Data Assimilation model for assimilating sea surface temperature (SST) values collected into the Caspian Sea by using the Regional Ocean Modeling System (ROMS) with observations provided by the Group of High resolution sea surface temperature (GHRSST). We also present the algorithmic strategies we employ

    The writing life: authorship and authority in recent American autobiographical narratives

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    I was a node in a new electronic landscape of celebrity, personality, and status, Norman Mailer wrote in 1959, describing the literary renown he earned after the publication of his first novel, The Naked and the Dead, a decade earlier. Mailer made his career as an active participant-observer in that landscape, alternately embracing and rebelling against his position and often featuring that role at the center of his texts. This project addresses the dual nature of the author as a cultural producer and product by examining self-representations in the works of Norman Mailer, John Edgar Wideman, and Dave Eggers. Their writing about themselves illustrates the tension in autobiographical narratives which requires individuals whose social identities are inherently connected to their authorship to acknowledge that position but also to humanize it by writing against their roles as public figures to reveal their private, inner selves. This dissertation enters ongoing critical and theoretical discussions of authorship, autobiography, and celebrity through analysis of texts, contexts, and paratexts--the apparatus which supports and surrounds a work's presentation to the world--in order to provide insight into the conflicting and overlapping interests of writers, publishers, and readers who are jointly invested in the ambiguity between the public and private personae of authors

    A New Wood Surface Flame-Retardant Based on Poly-m-Aramid Electrospun Nanofibers

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    Poly(meta-phenylene isophtalamide) (PMIA) was processed via electrospinning to provide nanofibrous membranes with randomly and aligned fibers. Mechanical performance of such membranes was evaluated, applying a normalization procedure that takes into account the peculiar morphology of such complex substrate where voids can sum up to almost 80% of the sample volume. Random and aligned fibers membranes are applied onto wood panels to test their fire resistance in cone calorimetry when coated in polyaramidic thin nanofiber mats. Tests highlighted that random fibers provide a better fire protection, increasing Time to Ignition and decreasing the Fire Performance Index. Another important parameter affecting the performance is the adhesive system used to apply the nanofibers onto wood that is able to significantly modify the fire performance of the polyaramidic-coated wood panels. POLYM. ENG. SCI., 2019. (c) 2019 Society of Plastics Engineer

    hospital anxiety and depression

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    Objective: The study investigate the presence of depressive disorders in patient who are taken in general hospital, to prevent and reduce the risk of developing a psychological pathology (anxious-depressive symptoms). Methods: We used two tests: 1. General Health Questionnaire (GHQ-12) by Goldberg, a self-report questionnaire, consisting of 12 items, used to estimate the probability of detecting non-psychotic mental disorders and problems in every day's activity. 2. Personal Health Questionnaire (PHQ), a self-report questionnaire, consisting of 10 items. It is a new tool for detecting individuals with ICD-10 depressive disorders, used to estimate the probability to individuate the presence of major depression symptoms, and minor depression symptoms. Tests have been administered to 140 subjects (males' experimental group, 32 subjects; males' control group, 20 subjects; females' experimental group 58 subjects; females' control group, 30 subjects) from eight departments of university hospital, medical faculty, and social services. Results: It can be noted that with GHQ-12, the presence of non-psychotic mental disorders does not come out: just the females' group, experimental and control, shows some problems with insomnia and stress. On the other hand, with PHQ, the presence of no great entity depressive symptoms comes out for all groups. In the experimental groups the quantity of depressive symptoms is greater than in the control groups. Conclusions: We have find the presence of a number of depressive symptoms into a hospitalized population. It is known that detecting such symptoms is important for protection and care of depressive disorders in hospitalized and nonhospitalized populations

    Nonlinear Projection-Based Approach for Generating Compact Models of Nonlinear Thermal Networks

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    A nonlinear projection-base approach for generating compact models of nonlinear thermal networks is proposed. This approach is an extension of Galerkin's method, based on the theory of kernels. High accuracy for large temperature variations and high compactness of the generated models can be obtained

    Morphological variability of upper paleolithic and mesolithic skulls from Sicily

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    Scenarios for the dispersal of Homo sapiens in Southern Europe and in the Mediterranean basin have been uncertain, given the scarceness of osteological samples and the simplicity of the proposed archaeologically-based settlement hypotheses. According to available data, the first anatomically modern humans entered Sicily during the Late Pleistocene, coming from the Italian peninsula. A presumably small Late Epigravettian population colonised coastal sites. Later, North-Western archaeological horizons gave hospitality to a significant Mesolithic expansion. In order to verify a hypothesis of continuity in the peopling of the island, we analyzed Sicilian skulls from the Late Epigravettian site of San Teodoro, Eastern Sicily (AMS14C dated at 14,500 BP) and from the Mesolithic period (14C dated from 9,500 to 8,500 BP) coming from various sites (Uzzo, Molara, Grotta d’Oriente) located on the North Western coast of the island. The aims were to test the biological variability through time within the island as well as to evaluate the relationships of Sicilian Pleistocene hunter-gatherers with Old World populations. We also evaluated the Sicilian Mesolithic uniformity especially between the Uzzo and Grotta d’Oriente sites, given their vicinity and accessibility during the Early Holocene. We applied 3D geometric morphometric methods to assess shape variation as well as geographic and diachronic morphological patterns. All analyzed specimens, plus a comparative sample from the Old World dated from the Upper Paleolithic to recent periods, were transformed in digital images and standard craniofacial landmarks were extracted from the 3D models. Our results underline a high variability among the Mesolithic specimens, as well as a large craniometric distance from the presumed founder Paleolithic settler representatives (San Teodoro specimens) that have closer morphological affinities with other European Upper Paleolithic specimens

    Canonical Forms of Multi-Port Dynamic Thermal Networks

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    In this paper it is shown that multi-port dynamic thermal networks admit four canonical representations which generalize the four canonical representations of passive lumped RC networks : Foster I and II canonical forms, Cauer I and Cauer II canonical forms. In particular the generalized Foster I canonical form is equivalent to the time-constant representation and the generalized Cauer I canonical form is a passive multi-conductor RC transmission line

    Impact of chemotherapy regimen and rituximab in adult Burkitt lymphoma: a retrospective population-based study from the Nordic Lymphoma Group.

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    BackgroundStandard treatment of adult Burkitt lymphoma is not defined due to the lack of randomised trials. In this situation, population-based data may represent a useful contribution in order to identify an optimal treatment strategy.Patients and methodsThe aims of this study were to investigate the outcome for adult HIV-negative BL with different chemotherapy regimens, and to assess possible improvement within the time frame of the study. The study population was identified through the Swedish and Danish lymphoma registries 2000-2009.ResultsA total of 258 patients were identified. Since 2000, overall survival (OS) improved significantly only for younger patients (<65 years). Intensive regimens such as the Berlin-Frankfurt-MĂĽnster, hyper-fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD) and cyclophosphamide, vincristine, doxorubicin, methotrexate, ifosfamide, etoposide, and cytarabine (CODOX-M/IVAC) were associated with a favourable 2-year OS of 82%, 83%, and 69%, respectively. The low-intensive CHOP/CHOEP regimens achieved a 2-year OS of 38.8%, confirming their inadequacy for the treatment of BL. In a multivariate analysis, rituximab was not significantly associated with improved OS.ConclusionsIn this population-based retrospective series of adult BL, intensive chemotherapy regimens were associated with favourable outcome. The impact of the addition of rituximab remains uncertain and warrants further investigation
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