Apparent phonon side band modes in pi-conjugated systems: polymers, oligomers and crystals

The emission spectra of many pi-conjugated polymers and oligomers contain side-band replicas with apparent frequencies that do not match the Raman active mode frequencies. Using a time dependent model we show that in such many mode systems, the increased damping of the time dependent transition dipole moment correlation function results in an effective elimination of the vibrational modes from the emission spectrum; subsequently causing the appearance of a regularly spaced progression at a new apparent frequency. We use this damping dependent vibrational reshaping to quantitatively account for the vibronic structure in the emission spectra of pi-conjugated systems in the form of films, dilute solutions and single crystals. In particular, we show that by using the experimentally measured Raman spectrum we can account in detail for the apparent progression frequencies and their relative intensities in the emission spectrum.Comment: Presented in "Optical Probes 2005", Bangalore, Indi

Geomatic training experiences for a high vulnerability cultural heritage item

The plan of Architectural documentation is the basic platform on which the CH protection and development process is founded; it embraces the historical analysis, the metric survey and the graphical representation of the object. It covers a primary importance in order to achieve very many objects: the comprehension of cultural values through the study of historical sources; the morphological and geometrical data collection and interpretation for the object representation. The latter is the frame on which we can organize the diagnostic tests, build the restoration plan and the communication and dissemination of his cultural values. The achievement of the know how in the field of the architectural and environmental survey is an important part of the curriculum in faculties of Architecture. The basic courses in this field of study (an integrated course named Topography/Metric Survey/IT and the course of Photogrammetry) approach to the main methods and the modern techniques of metric survey and at the same time the students will be provided of the basic knowledge for the critical analysis of the historical handiworks in the different scales, from the territorial to the architectural one. In the area of the optional courses, the educational program widen to involve all data capture methodologies, including the LIDAR techniques, and systems of 3D survey data management and integration. Modern spatial data products, such as DEM and vector surface models, are used for the final rendering, where both the 2D and 3D element will be integrated. It will be also introduced the GIS environment for the storage and management of spatial information at the territorial and architectural scales. In this paper we are going to present several experiences employed during two courses of the Faculty of Architecture (Applied Photogrammetry and Digital Photogrammetry/3D scanning for CH survey, the last managed by CISDA - Architecture Interdepartmental Teaching Services Centre)*. In this training experiences the methodological contents of disciplines have been exploited to obtain the documentation of a cultural item, featured by a high risk of extinction: the decorated gypsum ceilings of the southern Piedmon

Discourses of Distribution: Anchoring Educational Leadership to Practice

The paper deals with the fashioning idea of distributed leadership and the related issue of education ecology democratization. The analysis of distributed leadership theories is carried on using two interpretative dimensions: discourses as regimes of truth and ontological and epistemological presuppositions. This first dimension refers to the classical tripartition between welfarism (bureauprofessionalism), managerialism and democratic-critical discourse. The second dimension recalls Seddon’s distinction between categorical and relational education contexts and, drawing on Bottery’s and Gronn and Ribbins works, exploites it in the light of a focus on both human and practice ontologies. The paper shows three conceptions of distribution. The first one is recognisable through the connection between the ontology of practice and the welfarist discourse (distributed leadership in practice). Another conception could be called delegated, more than distributed, leadership because it stresses this idea from a managerialist perspective grounding on a human ontological basis. The third one refers to different conceptions such as dispersed or ecological leadership or to the anchoring of leadership practices to the social division of labour and to the power relationships in the field of education. The anchoring of leadership theories to the ontologies of practice, it is argued, is crucial to ‘discuss’ the idea of distribution in a democratic perspective

Competition between water and hydrogen peroxide at Ti center in Titanium zeolites. An ab initio study

A combined Car 12Parrinello molecular dynamics blue moon sampling approach has been adopted to study the competitive attack of H2O and H2O2 at a tetracoordinated Titanium site in a Ti 12zeolite. The results indicate that, although the attack of water to form a trigonal bipyramidal center is thermodynamically more stable, the attack of hydrogen peroxide to form a similar adduct is kinetically favored. In both cases, solvent cooperation is effective in the formation of the adducts. The relevance of such a result in relation to the catalytic properties of Ti 12zeolites is discussed

Taking control : Hijacking of Rab GTPases by intracellular bacterial pathogens

Work in the Spanò laboratory is supported by the Wellcome Trust (grant no. 109680/Z/15/Z), the Royal Society (grant no. RG150386), and the BBSRC (grant no. BB/N017854/1). Work in the Galán laboratory is supported by the National Institute of Allergy and Infectious Diseases (grants AI055472 and AI079022 to J.E.G.).Peer reviewedPostprin

VMXR: a EUD Environment for Virtual Merchandizing in XR

This paper presents the current development state of VMXR, a Proof of Concept (PoC) environment allowing people without programming experience to create and configure product showcases in a Virtual and eXtended reality setting. The aim of the PoC is to identify proper metaphors and workflows for supporting showcase designers in creating interactions with the virtual product representation or enhancing the physical environment through additional information and media

An S-band Ultrawideband Time Reversal-based RADAR for Imaging in Cluttered Media

This work presents a new RADAR prototype built for the purpose of imaging targets located in a cluttered environment. The system is capable of performing Phase Conjugation experiments in the ultrawideband [2-4] GHz. In addition, applying the D.O.R.T. method to the inter-element matrix allows us to selectively focus onto targets, hence reducing the clutter contribution. The system has been validated by phsyically backpropagating the focusing wave into the medium all over the frequency band and observing the expected focusing properties

Pseudo-Class III malocclusion treatment with Balters' Bionator.

The aim of this article is to show the use of the Balters' Bionator in pseudo-Class III treatment. The importance of differentiating between true Class III and pseudo-Class III is emphasized. The therapeutic results of a Balters' Bionator appliance are presented in three case reports of subjects in the mixed dentition. In this stage of development it is possible to correct an isolated problem. The use of the Bionator III in this kind of malocclusion enabled the correction of a dental malocclusion in a few months and therapeutic stability of a mesially-positioned mandible encouraging favourable skeletal growth

Drastic effects of damping mechanisms on the third-order optical nonlinearity

We have investigated the optical response of superradiant atoms, which undergoes three different damping mechanisms: radiative dissipation ($\gamma_r$), dephasing ($\gamma_d$), and nonradiative dissipation ($\gamma_n$). Whereas the roles of $\gamma_d$ and $\gamma_n$ are equivalent in the linear susceptibility, the third-order nonlinear susceptibility drastically depends on the ratio of $\gamma_d$ and $\gamma_n$: When $\gamma_d \ll \gamma_n$, the third-order susceptibility is essentially that of a single atom. Contrarily, in the opposite case of $\gamma_d \gg \gamma_n$, the third-order susceptibility suffers the size-enhancement effect and becomes proportional to the system size.Comment: 5pages, 2figure