1,207 research outputs found

    Aspectos sint谩cticos y discursivos de la nominalizaci贸n en un corpus de manuales escolares

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    El tratamiento de la nominalizaci贸n desde un punto de vista sint谩ctico y discursivo revela una serie de caracter铆sticas que se deber谩n tener presentes al analizar las realizaciones de los sintagmas que encabezan en un corpus textual. En primer lugar, es necesario observar la relaci贸n que mantiene la nominalizaci贸n con una cl谩usula de verbo finito, de la cual hereda la estructura argumental. Sin embargo, con respecto a dicha cl谩usula se pierden los significados que aporta la flexi贸n verbal, es decir, la modalidad y la temporalidad enunciativas as铆 como el aspecto de la acci贸n. Otro rasgo fundamental que desaparece con la nominalizaci贸n es el car谩cter activo o pasivo de la acci贸n en el caso de los verbos transitivos. Esto ha llevado a plantear la no recuperabilidad total de la cl谩usula que da origen a una nominalizaci贸n. Desde el punto de vista discursivo, la nominalizaci贸n deverbal permite al enunciador introducir en su enunciado objetos discursivos que han sido construidos en el discurso anterior (nominalizaci贸n anaf贸rica intradiscursiva) o bien presentarlos como preconstruidos, como ya dados de antemano. Al mismo tiempo, el enunciador puede o no saturar la estructura argumental del lexema nominalizado, de modo que los papeles tem谩ticos de agente, de paciente, de meta, etc. pueden estar expl铆citamente integrados en el sintagma como complementos, o bien ser recuperables a partir del contexto, o bien quedar vac铆os. La aparici贸n de nominalizaciones preconstruidas en un discurso permite observar la presencia del interdiscurso, en la medida en que el enunciador presenta un enunciado anterior, procedente de otro lugar como un objeto ya dado, de cuya aserci贸n no se hace cargo, pero que despliega la evidencia de lo consabido. A partir de estas consideraciones se analiza un corpus constituido por una serie de manuales escolares de Historia Argentina publicados entre 1980 y 2000, en los que el tratamiento de los gobiernos peronistas adquiere un particular inter茅s dado el grado de conflictividad pol铆tica que conlleva el tema en la sociedad argentina y, en consecuencia, en la educaci贸n p煤blica del ciudadan

    Evidence for narrow resonant structures at W1.68W \approx 1.68 and W1.72W \approx 1.72 GeV in real Compton scattering off the proton

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    First measurement of the beam asymmetry \Sigma for Compton scattering off the proton in the energy range E=0.851.25E_{\gamma}=0.85 - 1.25 GeV is presented. The data reveals two narrow structures at E=1.036E_{\gamma}= 1.036 and E=1.119E_{\gamma}=1.119 GeV. They may signal narrow resonances with masses near 1.681.68 and 1.721.72 GeV, or they may be generated by the sub-threshold KK\Lambda and p\omega p production. Their decisive identification requires additional theoretical and experimental efforts.Comment: Published versio

    Iron homeostasis and oxidative stress in idiopathic pulmonary alveolar proteinosis: a case-control study

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    <p>Abstract</p> <p>Background</p> <p>Lung injury caused by both inhaled dusts and infectious agents depends on increased availability of iron and metal-catalyzed oxidative stress. Because inhaled particles, such as silica, and certain infections can cause secondary pulmonary alveolar proteinosis (PAP), we tested the hypothesis that idiopathic PAP is associated with an altered iron homeostasis in the human lung.</p> <p>Methods</p> <p>Healthy volunteers (n = 20) and patients with idiopathic PAP (n = 20) underwent bronchoalveolar lavage and measurements were made of total protein, iron, tranferrin, transferrin receptor, lactoferrin, and ferritin. Histochemical staining for iron and ferritin was done in the cell pellets from control subjects and PAP patients, and in lung specimens of patients without cardiopulmonary disease and with PAP. Lavage concentrations of urate, glutathione, and ascorbate were also measured as indices of oxidative stress.</p> <p>Results</p> <p>Lavage concentrations of iron, transferrin, transferrin receptor, lactoferrin, and ferritin were significantly elevated in PAP patients relative to healthy volunteers. The cells of PAP patients had accumulated significant iron and ferritin, as well as considerable amounts of extracellular ferritin. Immunohistochemistry for ferritin in lung tissue revealed comparable amounts of this metal-storage protein in the lower respiratory tract of PAP patients both intracellularly and extracellularly. Lavage concentrations of ascorbate, glutathione, and urate were significantly lower in the lavage fluid of the PAP patients.</p> <p>Conclusion</p> <p>Iron homeostasis is altered in the lungs of patients with idiopathic PAP, as large amounts of catalytically-active iron and low molecular weight anti-oxidant depletion are present. These findings suggest a metal-catalyzed oxidative stress in the maintenance of this disease.</p

    Assessing the demographic impact of migration on the working-age population across European territories

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    Background: Ageing is central in the European Union (EU) policy debate, with all member states being concerned about implications of growing shares of older people and declining shares of working-age populations for the sustainability of welfare and health systems. Beyond this general context, ageing patterns differ largely across EU territories because of distinctive demographic and spatial dynamics. Objective: We study the relative contribution of cohort turnover and migration flows in shaping the demographic evolution of the working-age population at the local level. Methods: Using Eurostat data, we decompose the changes that have occurred in the working-age population into cohort turnover and net migration effects for the 2015鈥2019 period, at territorial (NUTS3 and urban-intermediate-rural) levels. Results: The majority (63%) of European (NUTS3) territories experienced negative cohort turnover effects alongside positive net migration effects during the 2015鈥2019 period. However, in only 27% of these territories, net migration counterbalanced the deficit in the working-age population due to cohort turnover. Conclusions: In 2015鈥2019, migration was the underlying force in the evolution of the working-age population, partially compensating for the loss of population due to the cohort turnover. This effect was particularly pronounced in urban areas. Contribution: Our contribution is twofold. First, we map EU NUTS3 territories where the working-age population is declining rapidly. Second, we give an assessment of the varied role of migration in mitigating the effect of ageing and shrinking working-age populations across EU urban, intermediate, and rural areas

    Is Venice an ideal habitat for Legionella pneumophila?

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    Introduction. Legionella bacterium manifests itself in Legion- naire?s disease and Pontiac fever, it is mainly found and trans- mitted by aerosol produced in cooling towers, water distribution plants and medical equipment, and it affects mainly elder persons in poor health. Methods. The population of Venice Local Health Unit was divided in two areas of study and the incidence of legionellosis in residents of Venice historical centre (Distretto Sanitario 1) and in residents of the mainland and coastal areas (Distretti Sanitari 2, 3, 4) was calculated. The cases were those notified to the Public Health Unit by law, and the population of residents was that of the eligible for health care in the archives of the Local Health Unit. Only cases of legionellosis in residents who had not travelled in the 10 days previous of the onset of disease, and not related to nosocomial clusters were considered. The standardized incidence ratio was then calculated and confidence interval were defined by Poisson distribution. Results. Given the population of the two areas, 59801 in Distretto Sanitario 1 and 237555 in Distretti 2, 3, 4, the raw incidence of disease is respectively 87 per 100000 and 20 per 100000 in time 2002-2010. The standardized incidence ratio for the population of Distretto Sanitario 1 vs the remaining population is 4.3. Discussion. The difference in risk of getting the disease in this two residential areas geographically very close, is probably related to the different buildings? characteristics, old and difficult to main- tain in Venice historical centre

    Experimental and numerical analysis of supersonic blade profiles developed for highly loaded impulse type steam turbine stages

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    The paper describes the results of a numerical and experimental research program addressing the aerodynamic investigation on the performance of blade profiles specifically developed for application in highly loaded impulse type turbine stages. The industrial requirements driving toward the adoption of highly loaded stage solutions are presented, along with an estimation of the profiles operating parameters. Two stator vanes and one rotor blade profile have been developed and extensively tested by means of flow field measurements and schlieren visualization in a transonic blow-down wind tunnel for linear cascades. Experimental results for the relevant operating conditions are presented, providing validation data for the CFD model used for blade design and evidencing that the main goals of the design optimization procedure have been achieved

    The GRAAL high resolution BGO calorimeter and its energy calibration and monitoring system

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    We describe the electromagnetic calorimeter built for the GRAAL apparatus at the ESRF. Its monitoring system is presented in detail. Results from tests and the performance obtained during the first GRAAL experiments are given. The energy calibration accuracy and stability reached is a small fraction of the intrinsic detector resolution.Comment: 19 pages, 14 figures, submitted to Nuclear Instruments and Method

    Deuteron photo-disintegration with polarised photons in the energy range 30 - 50 MeV

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    The reaction d(\vec\gamma,np) has been studied using the tagged and polarised LADON gamma ray beam at an energy 30 - 50 MeV to investigate the existence of narrow dibaryonic resonances recently suggested from the experimental measurements in a different laboratory. The beam was obtained by Compton back-scattering of laser light on the electrons of the storage ring ADONE. Photo-neutron yields were measured at five neutron angle \vartheta_n = 22, 55.5, 90, 125 and 157 degrees in the center of mass system.Our results do not support the existence of such resonances.Comment: 16 pages, Latex, 22 figures, 1 table. Nucl. Phys. A to appea

    Evidence for Narrow N*(1685) Resonance in Quasifree Compton Scattering on the Neutron

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    The first study of quasi-free Compton scattering on the neutron in the energy range of E=0.751.5E_{\gamma}=0.75 - 1.5 GeV is presented. The data reveals a narrow peak at W1.685W\sim 1.685 GeV. This result, being considered in conjunction with the recent evidence for a narrow structure at W1.68W\sim 1.68GeV in the \eta photoproduction on the neutron, suggests the existence of a new nucleon resonance with unusual properties: the mass M1.685M\sim 1.685GeV, the narrow width 30\Gamma \leq 30MeV, and the much stronger photoexcitation on the neutron than on the proton.Comment: Replaced with the version published in Phys. Rev.
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