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81.
82.
Paolo Baccarelli Fabrizio Frezza Alessandro Galli 《Journal of Infrared, Millimeter and Terahertz Waves》2001,22(10):1469-1484
In this work, a straightforward method is shown to derive spectral Green's functions in classes of planar structures including gyrotropic media, based on a recently proposed transmission-line formalism. In particular, the analysis is expressly carried out for a current line source in layered configurations with transversely-magnetized ferrites, useful for microwave and millimeter-wave waveguiding and radiating devices. 相似文献
83.
84.
The fundamental dynamic behaviour of a middle-vessel continuous distillation column is studied in this paper. The interaction between the middle vessel (MV) design and control parameters is identified by means of a linear analysis. Transfer functions relating the dynamics of the product composition responses to changes in the disturbance inputs and manipulated inputs are derived. The role of the MV holdup and MV level controller gain in altering the product composition responses is identified. It is shown that the MV level controller gain can significantly affect the control performance when feed flow disturbances must be compensated for. However, it has a much lower impact in the control performance when feed composition disturbances need to be rejected; in this case, exploiting the “buffering” effect of the MV is more important for control. The analysis is carried out in detail for a LV control configuration, and is subsequently extended to an “on-demand” DB configuration. Finally, simple guidelines for the choice of the MV level controller gain and MV holdup are provided. 相似文献
85.
Anna Stainer Paola Faverio Sara Busnelli Martina Catalano Matteo Della Zoppa Almerico Marruchella Alberto Pesci Fabrizio Luppi 《International journal of molecular sciences》2021,22(12)
Idiopathic pulmonary fibrosis (IPF), the most lethal form of interstitial pneumonia of unknown cause, is associated with a specific radiological and histopathological pattern (the so-called “usual interstitial pneumonia” pattern) and has a median survival estimated to be between 3 and 5 years after diagnosis. However, evidence shows that IPF has different clinical phenotypes, which are characterized by a variable disease course over time. At present, the natural history of IPF is unpredictable for individual patients, although some genetic factors and circulating biomarkers have been associated with different prognoses. Since in its early stages, IPF may be asymptomatic, leading to a delayed diagnosis. Two drugs, pirfenidone and nintedanib, have been shown to modify the disease course by slowing down the decline in lung function. It is also known that 5–10% of the IPF patients may be affected by episodes of acute and often fatal decline. The acute worsening of disease is sometimes attributed to identifiable conditions, such as pneumonia or heart failure; but many of these events occur without an identifiable cause. These idiopathic acute worsenings are termed acute exacerbations of IPF. To date, clinical biomarkers, diagnostic, prognostic, and theranostic, are not well characterized. However, they could become useful tools helping facilitate diagnoses, monitoring disease progression and treatment efficacy. The aim of this review is to cover molecular mechanisms underlying IPF and research into new clinical biomarkers, to be utilized in diagnosis and prognosis, even in patients treated with antifibrotic drugs. 相似文献
86.
Vincenzo Lombardo Fabrizio Nunnari Rossana Damiano Antonio Pizzo Cristina Gena 《Multimedia Systems》2008,14(6):385-393
This paper describes the application “Carletto the spider” in terms of the mapping with the canonical processes of media production.
“Carletto the spider” is a character-based guide to a historical site and implements the Dramatour approach for the design
of drama-based interactive presentations. Dramatization makes presentations more engaging, thus improving the reception of
the content by the user. The major technical issue of the approach is the segmentation of the presentation into audiovisual
units that are edited on-the-fly in a way that guarantees dramatic continuity while adapting to the user response. We describe
the workflow of the application and its mapping to the canonical processes of media production, envisaging possible standardizations
for the application portability. 相似文献
87.
Assessing landscape preferences: a visual choice experiment in the agricultural region of Märkische Schweiz,Germany 总被引:1,自引:0,他引:1
Kati Häfner Ingo Zasada Boris T. van Zanten Fabrizio Ungaro Mark Koetse Annette Piorr 《Landscape Research》2018,43(6):846-861
Natural amenities and the aesthetic value of agricultural landscapes are important territorial assets for improving rural tourism and the quality of the living environment. To identify which characteristics shape the visual quality of a landscape, a stated-preference survey was conducted (N = 200) using photorealistic landscape visualisations of four different landscape attributes (point green elements, linear green elements, crop diversity and presence of livestock). We estimated respondents’ preferences for landscape attributes, examined the extent of agreement among respondents and identified socio-economic factors influencing their responses. Results revealed that point elements had the highest general preference. About 70% of respondents preferred diverse and highly structured landscapes, while about 30% of respondents had opposing preferences. Preferences were also found to be dependent on the individual’s sociocultural background, such as their level of education, gender or age. These results can help to improve the multi-objective targeting of policies by including an aesthetic value perspective. 相似文献
88.
Small‐b and Fixed‐b Asymptotics for Weighted Covariance Estimation in Fractional Cointegration
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In a standard cointegrating framework, Phillips (1991) introduced the weighted covariance (WC) estimator of cointegrating parameters. Later, Marinucci (2000) applied this estimator to fractional circumstances and, like Phillips (1991), analysed the so‐called small‐b asymptotic approximation to its sampling distribution. Recently, an alternative limiting theory (fixed‐b asymptotics) has been successfully employed to approximate sampling distributions. With the purpose of comparing both approaches, we derive here the fixed‐b limit of WC estimators in a fractional setting, filling also some gaps in the traditional (small‐b) theory. We also provide some Monte Carlo evidence that suggests that the fixed‐b limit is more accurate. 相似文献
89.
G. Cojoc C. Liberale P. Candeloro F. Gentile G. Das F. De Angelis E. Di Fabrizio 《Microelectronic Engineering》2010,87(5-8):876-879
In this work we report, for the first time to our knowledge, the possibility to fabricate various structures, with good optical proprieties, on the top of optical fibers, using the two-photon lithography (TPL) technique. We show the convenience of this approach to quickly create generic 3D shapes using a single set-up by contrast to past shape-dependent methods. A set of different structures are fabricated and characterized to demonstrate the versatility of this approach and their high optical quality. 相似文献
90.
Bazzicalupi C Chioccioli M Sissi C Porcù E Bonaccini C Pivetta C Bencini A Giorgi C Valtancoli B Melani F Gratteri P 《ChemMedChem》2010,5(12):1995-2005
Three novel 2,7-substituted acridine derivatives were designed and synthesized to investigate the effect of this functionalization on their interaction with double-stranded and G-quadruplex DNA. Detailed investigations of their ability to bind both forms of DNA were carried out by using spectrophotometric, electrophoretic, and computational approaches. The ligands in this study are characterized by an open-chain (L1) or a macrocyclic (L2, L3) framework. The aliphatic amine groups in the macrocycles are joined by ethylene (L2) or propylene chains (L3). L1 behaved similarly to the lead compound m-AMSA, efficiently intercalating into dsDNA, but stabilizing G-quadruplex structures poorly, probably due to the modest stabilization effect exerted by its protonated polyamine chains. L2 and L3, containing small polyamine macrocyclic frameworks, are known to adopt a rather bent and rigid conformation; thus they are generally expected to be sterically impeded from recognizing dsDNA according to an intercalative binding mode. This was confirmed to be true for L3. Nevertheless, we show that L2 can give rise to efficient π-π and H-bonding interactions with dsDNA. Additionally, stacking interactions allowed L2 to stabilize the G-quadruplex structure: using the human telomeric sequence, we observed the preferential induction of tetrameric G-quadruplex forms. Thus, the presence of short ethylene spacers seems to be essential for obtaining a correct match between the binding sites of L2 and the nucleobases on both DNA forms investigated. Furthermore, current modeling methodologies, including docking and MD simulations and free energy calculations, provide structural evidence of an interaction mode for L2 that is different from that of L3; this could explain the unusual stabilizing ability of the ligands (L2>L3>L1) toward G-quadruplex that was observed in this study. 相似文献