251 research outputs found

    Quality control facilities for large optical reflectors at ENEA-Casaccia for physics application

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    The paper describes the quality control facilities for large optical reflectors available at ENEA-Casaccia. Commercial and custom spectrophotometers allow to measure the reflectance; specular and diffused for flat samples, and specular for the full-size reflector. In the case of spherical shape, the 2f and the pin-hole optical tests give a quick evaluation of the focusing effectiveness and the curvature uniformity, respectively. An optical profilometer allows to accurately measure the reflector profile and its deviations from the project specifications

    Enhanced equivalent model algorithm for solar mirrors

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    The SolarPACES Reflectance Guideline provides an essential tool to obtain comparable reflectance measurements, but because of the lack of adequate commercial instrumentation, till now the exhaustive characterization of reflectance behaviour versus incidence ¿i and (half) acceptance angle ¿ is unachieved. An expert group in Task III has been working to outline some practicable solutions. The Equivalent Model Algorithm (EMA) was found quite promising: with few input data, EMA allows to predict any reflectance feature by computation. The recent availability of reliable reflectance measurements at oblique incidence made possible the refinement of EMA by analysing a representative set of commercial solar mirrors. This paper describes the new EMA for solar mirror, named EMA4SM, and reports its validation

    DENS INVAGINATUS (DENS IN DENTE): A MULTIDISCIPLINARY APPROACH. CASE REPORT

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    Aim: The purpose of this report was to demonstrate how a multidisciplinary surgical and endodontic approach in this type of tooth anomaly, may improve the prognosis both functionally and aesthetically. Dens invaginatus is a developmental anomaly resulting from infolding of the surface of the tooth crown before calcification has occurred. Many mechanisms have been proposed as a cause of this phenomenon, including local delay in enamel formation, infolding of the enamel organ within the dental pulp and local external influences on the tooth germ, but the aetiology of dens in dente is still not entirely known. The most common teeth interested by this malformation are maxillary lateral incisors, sometimes it occurs bilaterally. Morphologically the malformation is classified in three types: Type I: An enamel-lined minor invagination occurring within the crown not extending beyond the amelocemental junction. Type II: An enamel-lined form that invades the root but remains confined as a blind sac. It may or not communicate with dental pulp. Type III: a form that penetrates through the root perforating at the apical area showing “a second foramen” in the apical or periodontal area. There is no immediate communication with the pulp. The invagination may be completely lined by enamel, but frequently cementum will be found lining the invagination. The invagination commonly communicates with the oral cavity, allowing the entry of irritants and microorganisms either to the pulpal tissue or to an area that is only separated from pulpal tissue by a thin layer of dentin or enamel. This continual admission of irritants and the consequent inflammation usually leads to necrosis of the adjacent pulpal tissue and induces a periodontal or apical abscess. Other reported sequels of undiagnosed and untreated invaginated teeth include cysts, delay eruption and internal resorption. Sometimes Dens in Dente is associated with dental anomalies like taurodontia, microdontia, supernumerary teeth, gemination, and dentinogenesis imperfecta. Description and procedures: A 24- year old male patient came to the Dental Clinic for aesthetic reasons. Intraoral examination disclosed the presence of a maxillary right lateral incisor with unusual morphological features. The crown of the tooth had a peg-shaped appearance. Radiological evaluation showed that a large periapical lesion existed corresponding to the area of the lateral incisor, and irregular root canal borders and an enamel-lined invagination extended through the root. A Type III Dens Invaginatus was diagnosed. The patient was invited to have a maxillary Dental Scan done that showed exactly the wideness of the bone loss. After several irrigations with 5% NaClO, the endodontic treatment was performed: Ca(OH)2 was left in the root canal for one month and then Thermafil Obturators (Dentsply, Maillefer) were used for endodontic closure. After eight months, although the initial improvement , we decided for the surgical removal of the cysts and apicectomy of the tooth. Conclusion: Dens invaginatus has an unpredictable root canals anatomy. For a good clinical outcome we need to associate the surgical approach with the endodontic treatment

    Indicatori microscopici di pascolo per ricostruzioni di paleoeconomia e paleoambiente: polline, spore di funghi coprofili e uova di parassiti

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    The paper reports two study cases showing integrated analyses of microscopic records (pollen, coprophilous fungi and parasites remains) which are of basic importance to reconstruct past breeding and pastoral activities in Italy. The sites are located at Piano Locce (1225 m a.s.l., Barisciano, L’Aquila) in a depression in a mountain area and in the Bradano Valley (about 150-500 m a.s.l., Basilicata) in a hilly area rich in archaeological sites. The pollen-based palaeoenvironmental reconstruction of Piano Locce provided the history of plants landscape from around 36.000 years BP. Before the Holocene, a steppe vegetation and a grassland characterized the area where wild animals freely browsed. This assumption is strongly supported by the association of spores of coprophilous fungi with intestinal parasites eggs (Dicrocoelium) and pollen clumps. The trend of coprophilous fungi and pollen assemblages including Anthropogenic Indicators shows that, after the wild animals browsing, a fairly continuous presence of domesticated animals, prevalently ovicaprines, interested the area in the Holocene. The archaeological sites of Difesa San Biagio and Altojanni in Bradano Valley showed evidences of ovicaprine-farming and cattle breeding during Hellenistic and Mediaeval periods. In particular, Cichorioideae, Chenopodiaceae and Brassicaceae pollen and spores of coprophilous fungi (such as Sordaria type, Sporormiella and Podospora type) attest the predominance of pastoral activities during the Hellenistic period at San Biagio. A greater pollen biodiversity characterizes Altojanni, where spores of the coprophilous fungi were associated with spores of fungi with a different ecology as Chaetomium and Valsaria variospora type. The environmental and microarchaeobotanical contexts are in agreement with archaeological evidences that attest the presence of domestic animals, probably cattle, maintained in this site during Middle Ages

    Investigation into the Coupling of Micro Gas Turbines with CSP Technology: OMSoP Project☆

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    Abstract Solar power generation has been gaining worldwide increasing interest by virtue of its ability to meet both the growing energy needs and the increasing concerns on the carbon dioxide emissions. One of the most promising Concentrated Solar Power (CSP) technologies under development uses a parabolic dish to concentrate solar power into a focal point, raising thetemperature of a working fluid which is then used in a thermodynamic cycle to generate electricity. In the OMSoP project, funded by the European Commission, it is proposed to use a Brayton cycle in the form of a micro-gas turbine (MGT), which replaces the more conventional Stirling engine,with the aim of increasing the ratio of the electric power generated to the solar energy collected and improving the operability in relation to solar energy short time fluctuations. To achieve these objectives, research and development will be conducted in all aspects of the system leading to a full scale demonstrative plant to be located at the ENEA Casaccia Research Centre.The present work deals with the activities carried out so far by ENEA, which is principally involved in the development and experimental characterization of the dish component, and in the integration of the complete system, both in terms of modelling and realization

    Establishing comprehensive oral assessments for children with safeguarding concerns.

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    The dental profession is well placed to contribute important information in child protection cases but no previous research has been reported that assesses the volume or impact of this information. Comprehensive oral assessment clinics were introduced and established as an integral part of comprehensive medical assessments for children with welfare concerns in Greater Glasgow and Clyde. An assessment protocol and standardised paperwork for comprehensive oral assessments were developed to enhance information sharing and patient access to appropriate care. Two cases are presented and discussed to demonstrate the value of dental input

    New insights on the interaction between thiophene derivatives and Au surfaces: the case of 3,4-ethylenedioxythiophene and the relevant polymer.

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    The nature of the interface between electrogenerated poly(3,4-ethylenedioxythiophene) and the Au substrate is studied in detail. In particular, the adsorption of the relevant monomer, namely, 3,4-ethylenedioxythiophene, is investigated and compared with that of other thiophene derivatives. Different deposition procedures have been adopted: very thin films of the thiophene derivatives have been obtained through chemisorption processes from vapor and liquid phases, on Au polycrystalline substrates, Au nano particles possessing different size, and a Au(111) single crystal. Different techniques, operating both in situ and ex situ, have been employed for the characterization of these deposits, that is, X-ray photoemission and surface enhanced Raman spectroscopy. The results show that the poly(3,4-ethylenedioxythiophene)/metal interface is far from being simply constituted by unreacted molecules in contact with the substrate; rather, the formation of oligothiophene species and sulfur atoms at the interface has been ascertained

    Role of gallium diffusion in the formation of a magnetically dead layer at the Y3Fe5O12/Gd3Ga5O12 epitaxial interface

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    We have clarified the origin of a magnetically dead interface layer formed in yttrium iron garnet (YIG) films grown at above 700 degrees C onto a gadolinium gallium garnet (GGG) substrate by means of laser molecular beam epitaxy. The diffusion-assisted formation of a Ga-rich region at the YIG/GGG interface is demonstrated by means of composition depth profiling performed by x-ray photoelectron spectroscopy, secondary ion mass spectroscopy, and x-ray and neutron reflectometry. Our finding is in sharp contrast to the earlier expressed assumption that Gd acts as a migrant element in the YIG/GGG system. We further correlate the presence of a Ga-rich transition layer with considerable quenching of ferromagnetic resonance and spin wave propagation in thin YIG films. Finally, we clarify the origin of the enigmatic low-density overlayer that is often observed in neutron and x-ray reflectometry studies of the YIG/GGG epitaxial system

    The SUCCESSO-TERRA project: A lesson of sustainability from the terramare culture, middle bronze age of the po plain (Northern Italy)

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    This backstory article deals with the SUCCESSO-TERRA Project (2017–2020), an interdisciplinary research program aiming at reconstructing the land-use transformations that occurred during the development of the Terramare culture in the southern-central Po Plain of Northern Italy. Topics include climate-environment changes, human impact and exploitation of natural resources that are interconnected topics in human ecology and environmental sciences. These topics can only be understood in a long-term perspective integrating archaeology, geology, botany and other sciences. The text includes the theoretical basis, the research strategy and the main methodological approaches given by geoarchaeology and palynology, the two research sides constituting the partnership of the project
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