159 research outputs found

    Focus, Neg-concord, and Negative Postverbal Subjects

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    This paper concerns negative subjects occurring in the non-canonical postverbal position, where their distribution diverges from that of non-negative postverbal subjects (in contrast, both negative and non-negative subjects may occur in the canonical pre-auxiliary position frequently identified as SpecTP). The paper examines negative postverbal subjects with respect to contrastive focalization, right-dislocation, and neg-concord, showing how the constraints on these three operations fully determine their postverbal distribution. This achievement is dependent on an in situ analysis of postverbal contrastive foci. For this reason, the paper also examines the position of postverbal foci, providing several arguments in support of in situ focalization

    Enhanced Transmission and Reflection of Femtosecond Pulses by a Single Slit

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    We show that a physical mechanism responsible for the enhanced transmission and reflection of femtosecond pulses by a single subwavelength nanoslit in a thick metallic film is the Fabry-Perot-like resonant excitation of stationary, quasistationary and nonstationary waves inside the slit, which leads to the field enhancement inside and around the slit. The mechanism is universal for any pulse-scatter system, which supports the stationary resonances. We point out that there is a pulse duration limit below which the slit does not support the intraslit resonance.Comment: 4 pages, 3 figure

    Resonant backward scattering of light by a two-side-open subwavelength metallic slit

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    The backward scattering of TM-polarized light by a two-side-open subwavelength slit in a metal film is analyzed. We show that the reflection coefficient versus wavelength possesses a Fabry-Perot-like dependence that is similar to the anomalous behavior of transmission reported in the study [Y. Takakura, Phys. Rev. Lett. \textbf{86}, 5601 (2001)]. The open slit totally reflects the light at the near-to-resonance wavelengths. In addition, we show that the interference of incident and resonantly backward-scattered light produces in the near-field diffraction zone a spatially localized wave whose intensity is 10-103^3 times greater than the incident wave, but one order of magnitude smaller than the intra-cavity intensity. The amplitude and phase of the resonant wave at the slit entrance and exit are different from that of a Fabry-Perot cavity.Comment: 5 figure

    The interaction of Focus and Givenness in Italian clause structure

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    This book provides an in-depth investigation of contrastive focalization in Italian, showing that its syntactic expression systematically interacts with the syntactic expression of discourse-given phrases. Vieri Samek-Lodovici disentangles the properties genuinely associated with contrastive focalization from those determined by highly productive operations affecting discourse given phrases in Italian, namely right dislocation and marginalization. Based on a vast aggregate of evidence, he shows that in the default case contrastive focalization occurs in situ and that left-peripheral focalization patterns arise from the interaction with right dislocation and generalize well beyond the familiar cases examined in Rizzi (1997) and most literature since. In the final chapter, the author examines how the key properties unveiled in the previous chapters, such as focalization in situ, follow from the prosodic constraints governing stress placement, thus reinterpreting and extending Zubizarreta's (1998) insight about the role of prosody in shaping syntax

    Enhanced transmission versus localization of a light pulse by a subwavelength metal slit: Can the pulse have both characteristics?

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    The existence of resonant enhanced transmission and collimation of light waves by subwavelength slits in metal films [for example, see T.W. Ebbesen et al., Nature (London) 391, 667 (1998) and H.J. Lezec et al., Science, 297, 820 (2002)] leads to the basic question: Can a light be enhanced and simultaneously localized in space and time by a subwavelength slit? To address this question, the spatial distribution of the energy flux of an ultrashort (femtosecond) wave-packet diffracted by a subwavelength (nanometer-size) slit was analyzed by using the conventional approach based on the Neerhoff and Mur solution of Maxwell's equations. The results show that a light can be enhanced by orders of magnitude and simultaneously localized in the near-field diffraction zone at the nm- and fs-scales. Possible applications in nanophotonics are discussed.Comment: 5 figure

    Fitocenosis en los Pinares de Monte Cristo, Cuba oriental

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    Se realiza una caracterización general de las fitocenosis presentes en Monte Cristo y se pone de manifiesto, que es aquí donde único crece el Pinus cubensis sobre suelos derivados de calizas. Utilizando la metodología de Braun Blanquet se describe la asociación Alvaradoo arborescentis-Pinetum cubensis y sus dos subasociaciones: typicum y colubrinetosum ferrugineae que viven sobre suelos procedentes de la caliza. A su vez se estudian las asociaciones: Gundlachio cubanae-Pinetum cubensis y Lepidaploo orbicularis-Pinetum cubensis que se desarrollan sobre las ofiolitas, la primera sobre suelos ferríticos y la segunda en suelos esqueléticos

    La politica regionale di sviluppo della Valle d'Aosta 2007/13. Rapporto di monitoraggio al 31.12.2011

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    Rapporto periodico di monitoraggio delle performance della Politica regionale di sviluppo 2007/13 in Valle d'Aost

    La politica regionale di sviluppo della Valle d'Aosta 2007/13. Rapporto di valutazione 2010

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    La Politica regionale di sviluppo della Valle d’Aosta per il periodo 2007/13 interpreta gli obiettivi e gli orientamenti comunitari per la coesione economica, sociale e territoriale, esplicitando nel Documento unitario di programmazione (DUP) la strategia regionale per i nove Programmi che intervengono in Valle d’Aosta, con cofinanziamenti, a finalità strutturale, di provenienza comunitaria, statale e regionale stimati in oltre 363 milioni di euro. Il 2° Rapporto di valutazione della Politica regionale di sviluppo fa riferimento ai dati di attuazione al 30 giugno 2010 ed è stato predisposto a cura del NUVAL, Nucleo di valutazione dei programmi a finalità strutturale

    Laser-induced breakdown spectroscopy: a tool for real-time, in vitro and in vivo identification of carious teeth

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    BACKGROUND: Laser Induced Breakdown Spectroscopy (LIBS) can be used to measure trace element concentrations in solids, liquids and gases, with spatial resolution and absolute quantifaction being feasible, down to parts-per-million concentration levels. Some applications of LIBS do not necessarily require exact, quantitative measurements. These include applications in dentistry, which are of a more "identify-and-sort" nature – e.g. identification of teeth affected by caries. METHODS: A one-fibre light delivery / collection assembly for LIBS analysis was used, which in principle lends itself for routine in vitro / in vivo applications in a dental practice. A number of evaluation algorithms for LIBS data can be used to assess the similarity of a spectrum, measured at specific sample locations, with a training set of reference spectra. Here, the description has been restricted to one pattern recognition algorithm, namely the so-called Mahalanobis Distance method. RESULTS: The plasma created when the laser pulse ablates the sample (in vitro / in vivo), was spectrally analysed. We demonstrated that, using the Mahalanobis Distance pattern recognition algorithm, we could unambiguously determine the identity of an "unknown" tooth sample in real time. Based on single spectra obtained from the sample, the transition from caries-affected to healthy tooth material could be distinguished, with high spatial resolution. CONCLUSIONS: The combination of LIBS and pattern recognition algorithms provides a potentially useful tool for dentists for fast material identification problems, such as for example the precise control of the laser drilling / cleaning process

    La politica regionale di sviluppo della Valle d'Aosta 2007/13. Rapporto di valutazione 2010

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    La Politica regionale di sviluppo della Valle d'Aosta per il periodo 2007/13 interpreta gli obiettivi e gli orientamenti comunitari per la coesione economica, sociale e territoriale, esplicitando nel Documento unitario di programmazione (DUP) la strategia regionale per i nove Programmi che intervengono in Valle d'Aosta, con cofinanziamenti, a finalità strutturale, di provenienza comunitaria, statale e regionale stimati in oltre 363 milioni di euro. Il 2° Rapporto di valutazione della Politica regionale di sviluppo fa riferimento ai dati di attuazione al 30 giugno 2010 ed è stato predisposto a cura del NUVAL, Nucleo di valutazione dei programmi a finalità struttural
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