163 research outputs found

    Circadian sleep propensity and alcohol interaction at the wheel

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    Study Objectives: The study was aimed at estimating the effect of alcohol consumption, time of day, and their interaction on traffic crashes in a real regional context. Methods: Blood alcohol concentration (BAC) data were collected from drivers involved in traffic accidents during one year in an Italian region and in a control group of drivers over the same road network. Mean circadian sleep propensity was estimated from a previous study as function of time of day. Accident risk was analyzed by logistic regression as function of BAC and circadian sleep propensity. Results: BAC values greater than zero were found in 72.0% of the drivers involved in crashes and in 40.4% of the controls. Among the former 23.6% of the drivers exceeded the BAC legal threshold of 0.05 g/dL, while illegal values were found in 10.4% of the controls. The relative risk showed a significant increase with both BAC and circadian sleep propensity (as estimated from time of day) and their interaction was significant. Conclusions: Due to the significant interaction, even low BAC levels strongly increased accident risk when associated with high sleep propensity

    A CONTABILIDADE GERENCIAL E O MARKETING NO PLANEJAMENTO EMPRESARIAL: O CASO DO SUPERMERCADO DO COLONO

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    A área de marketing auxilia na divulgação, comercialização, planejamento da distribuição dos produtos, preço, comunicação e propaganda. A análise contábil demonstra o andamento da empresa, mostrando um histórico de altos e baixos que surgem ao longo do tempo, através da observação desses dados verificam-se pontos onde devem ser melhorados. Analisar as duas áreas em conjunto trazem sugestões satisfatórias para e empresa. Desta forma, o estudo teve como objetivo analisar a contabilidade e elaborar estratégias de marketing a partir dos dados apresentados. Num primeiro momento foi feita uma análise dos dados contábeis dos dois últimos anos da empresa, através dos balanços e DRE da empresa. Posteriormente foi realizada uma pesquisa de satisfação com os clientes, usando-se a escala Likert, e o autor GARVIN (1988), analisando a qualidade do produto em oito dimensões, com um questionário de vinte e duas questões e transformado em gráficos os resultados obtidos. Com os dados obtidos foi possível propor estratégias de marketing para a organização

    An educational method for evaluating the resistance to the treatment in the diagnosis of dyscalculia

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    In this paper a didactical method that has been proven effective for evaluating the “resistance to the treatment” of the student is presented. This parameter is essential for distinguishing the learning difficulties in mathematics from the learning disorder of dyscalculia. The method is based on GimmeFive, an application that has been designed to develop skills in mental calculation of multi-digit additions and subtractions. In this paper we present the results of two experiments conducted with groups of students respectively with learning difficulties in mathematics and dyscalculia. These experiments allowed to show the effectiveness of the didactical method in the evaluation of the resistance to the treatment and to discuss the features that make it adequate for the evaluation of the learning disorder. An educational method for evaluating the resistance to the treatment in the diagnosis of dyscalculiaIn questo lavoro viene presentato un metodo didattico che si è dimostrato efficace per valutare la resistenza al trattamento dello studente che è uno dei parametri fondamentali per distinguere la difficoltà di apprendimento in matematica dal disturbo di apprendimento noto come discalculia. Il metodo si basa sull’uso dell’applicazione GimmeFive che è stata progettata per sviluppare competenze nel calcolo mentale di addizioni e sottrazioni a più cifre. In questo lavoro vengono presentati risultati di due sperimentazioni condotte con gruppi di studenti rispettivamente con difficoltà di apprendimento e con diagnosi di discalculia. Queste sperimentazioni hanno consentito di mostrare l’efficacia del metodo didattico nella valutazione della resistenza al trattamento e di discutere le caratteristiche che lo rendono adeguato per la valutazione del disturbo di apprendimento

    Spectral characterization of volcanic rocks in the VIS-NIR for martian exploration

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    Igneous effusive rocks cover much of the surface of Mars [1,2,3]. Initially only two types of lithologies were thought to constitute the Martian crust, i.e. a basaltic one and a more andesitic one [1,2], while more evolved lithologies were ruled out.Nevertheless a more complex situation is appearing in the last years. Recently several observations have highlighted the presence of evolved, acidic rocks. High-silica dacite units were identified in Syrtis Major caldera by thermal IR data [4]. Outcrops in Noachis Terra were interpreted as constituted of felsic (i.e. feldspar-rich) rocks essentially by the observation of a 1.3-µm spectral feature in CRISM data, attributed to Fe2+ in feldspars [5]. However different interpretations exist, invoking plagioclase-enriched basalts [6] rather than felsic products.The increasing of high-resolution and in-situ rover-based observations datasets and the changing of the initial paradigm justify a new systematic spectral study of igneous effusive rocks. In this work we focus on the spectral characterization of volcanic effusive rocks in the 0.35-2.5-µm range. We are carrying out measurements and spectral analyses on a wide ensemble of effusive samples, from mafic to sialic, with variable alkali contents, following the classification in the Total-Alkali-Silica diagram, and discussing the influence on spectral characteristics of different mineral assemblages and/or texture ([7], [8]). [1] Bandfield J.L., et al., Science, 287, 1626, 2000; [2] Christensen P.R., et al., J. Geophys. Res., 105, N.E4, 9609-9621, 2000; [3] Ehlmann B.L. & Edwards C.S., Annu. Rev. Earth Planet. Sci., 42, 291-315, 2014; [4] Christensen P.R., et al., Nature, 436, 504-509, 2005; [5] Wray J.J., et al., 44th LPSC, abs. n.3065, 2013; [6] Rogers A.D. & Nekvasil H., Geophys. Res. Lett., 42, 2619-2626, 2015; [7] Carli C. and Sgavetti M.,Icarus, 211, 1034-1048, 2011; [7] Carli C. et al., SGL, doi 10.1144/SP401.19, 2015. <P /

    Un metodo didattico per sviluppare competenze nel calcolo mentale di addizioni e sottrazioni a piĂą cifre in studenti con difficoltĂ  o con disturbo di apprendimento

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    The article presents the results of a controlled experiment designed to evaluate a teaching method aimed at developing mental calculation competencies in students with learning difficulties or disorder. The method exploits touch-screen technology to give students the means to have an Immersive Learning Experience of the strategies that experts use in mental calculation. The strategies that may be involved in mental calculation of multi-digit addition and subtraction are presented along with the ways in which these strategies are incorporated into the application used in the experiment. Ten students with learning difficulties or disorder were involved in the experiment and underwent three-months training by touch-screen application following a standardized protocol. Their performance was evaluated by a standardized test performed at the beginning and at the end of the experiment, by two questionnaires and by a final test of acquired mathematical skills. Statistical analysis showed a significant increase of the mean score at the standard addition/ subtractiontest and most students, following the training, achieved a score in the normal range. The present findings indicate an effective and reproducible approach for the development of an inclusive teaching practice of mental calculation within the school context

    Hyperspectral Imaging of HEDs: A new Approach to Investigate VNIR Spectral Properties of Meteorites

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    We present a preliminary study on VNIR hyperspectral imaging of HED samples. We integrate the high spatial resolution VNIR images acquired by SPIM with the mineral chemistry, Scanning Electron Microscope element maps and petrographic description

    Temperature-dependent VNIR spectroscopy of hydrated Na-carbonates

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    The surfaces of the Galilean icy satellites Europa, Ganymede and Callisto, dominated by water ice, also show substantial amounts of non-water-ice compounds. These satellites will be the subject of close exploration by the ESA JUICE mission and the NASA Europa Multiple-Flyby Mission, which will focus on Ganymede and Europa, respectively. Among non-water-ice compounds thought to exist on the surfaces of the Jovian icy satellites, hydrated salt minerals have been proposed to exist as a by-product of endogenic processes. Safe detection of these minerals shall rely on laboratory spectroscopic analysis of these materials carried out under appropriate environmental conditions. Here we report on laboratory measurements, carried out in the framework of a Europlanet Transnational Access (TA) 2020 proposal approved in 2016, on two hydrated sodium carbonates, namely sodium carbonate monohydrate (Na2CO3·1H2O) and sodium carbonate decahydrate (Na2CO3·10H2O). Spectral profiles of these compounds were obtained in the visible and near-infrared (VNIR) spectral domain, taking advantage of the Cold Surfaces spectroscopy facility at the Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), where such compounds can be measured under cryogenic conditions indicative of real planetary surfaces. Carbonates were first sieved so as to separate them in three different grain size ranges: 20-50 μm, 75-100 μm, and 125-150 μm. These grain sizes have been chosen to: (1) be indicative of typical regoliths known or expected to exist on the surface of the icy satellites, and (2) avoid overlapping between ranges, therefore minimizing particles contamination among the dimensional classes. Each grain size was then measured with the Spectro-Gonio-Radiometer facility in the overall 0.5-4.0 μm spectral range, with spectral sampling increasing with increasing wavelength. For each sample, the overall 93-279 K temperature ramp was acquired in 11 steps varying from 10 K to 25 K, imposed by time constraints. In particular, the uppermost temperature, 279 K, has been acquired both at the beginning and at end of the ramp, to check for any macroscopic physico-chemical changes in the sample. In sodium carbonate monohydrate, about ten spectral signatures are revealed in the spectral range 1.0-3.0 µm. These signatures are due in part to combinations and overtones of the fundamental vibration modes of the water molecule, and in part to the carbonate. For comparison, sodium carbonate decahydrate shows fewer diagnostic and generally wider signatures, due to the larger number of water molecules existing in this mineral. We analyzed the spectral behavior of the diagnostic signatures of these two hydrated minerals as a function of both grain size and temperature, deriving trends related to specific spectral parameters such as band center, band depth, band area, and bandwidth. We plan to complete this set of measurements with those obtained for anhydrous sodium carbonate, which serves as a valid comparison for the hydrated carbonates discussed here and may provide a valid support to spectroscopic analysis of bright faculae discovered by the NASA Dawn mission in crater Occator on the dwarf planet Ceres

    The role of spectrophotometry in the diagnosis of melanoma

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    Background. Spectrophotometry (SPT) could represent a promising technique for the diagnosis of cutaneous melanoma (CM) at earlier stages of the disease. Starting from our experience, we further assessed the role of SPT in CM early detection. Methods. During a health campaign for malignant melanoma at National Cancer Institute of Naples, we identified a subset of 54 lesions to be addressed to surgical excision and histological examination. Before surgery, all patients were investigated by clinical and epiluminescence microscopy (ELM) screenings; selected lesions underwent spectrophotometer analysis. For SPT, we used a video spectrophotometer imaging system (Spectroshade® MHT S.p.A., Verona, Italy). Results. Among the 54 patients harbouring cutaneous pigmented lesions, we performed comparison between results from the SPT screening and the histological diagnoses as well as evaluation of both sensitivity and specificity in detecting CM using either SPT or conventional approaches. For all pigmented lesions, agreement between histology and SPT classification was 57.4%. The sensitivity and specificity of SPT in detecting melanoma were 66.6% and 76.2%, respectively. Conclusions. Although SPT is still considered as a valuable diagnostic tool for CM, its low accuracy, sensitivity, and specificity represent the main hamper for the introduction of such a methodology in clinical practice. Dermoscopy remains the best diagnostic tool for the preoperative diagnosis of pigmented skin lesions

    Sleep in the Human Hippocampus: A Stereo-EEG Study

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    Background. There is compelling evidence indicating that sleep plays a crucial role in the consolidation of new declarative, hippocampus-dependent memories. Given the increasing interest in the spatiotemporal relationships between cortical and hippocampal activity during sleep, this study aimed to shed more light on the basic features of human sleep in the hippocampus. Methodology/Principal Findings. We recorded intracerebral stereo-EEG directly from the hippocampus and neocortical sites in five epileptic patients undergoing presurgical evaluations. The time course of classical EEG frequency bands during the first three NREM-REM sleep cycles of the night was evaluated. We found that delta power shows, also in the hippocampus, the progressive decrease across sleep cycles, indicating that a form of homeostatic regulation of delta activity is present also in this subcortical structure. Hippocampal sleep was also characterized by: i) a lower relative power in the slow oscillation range during NREM sleep compared to the scalp EEG; ii) a flattening of the time course of the very low frequencies (up to 1 Hz) across sleep cycles, with relatively high levels of power even during REM sleep; iii) a decrease of power in the beta band during REM sleep, at odds with the typical increase of power in the cortical recordings. Conclusions/Significance. Our data imply that cortical slow oscillation is attenuated in the hippocampal structures during NREM sleep. The most peculiar feature of hippocampal sleep is the increased synchronization of the EEG rhythms during REM periods. This state of resonanc
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