1,280 research outputs found
Near-field electrospinning of conjugated polymer light-emitting nanofibers
The authors report on the realization of ordered arrays of light-emitting
conjugated polymer nanofibers by near-field electrospinning. The fibers, made
by poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene], have diameters of
few hundreds of nanometers and emission peaked at 560 nm. The observed
blue-shift compared to the emission from reference films is attributed to
different polymer packing in the nanostructures. Optical confinement in the
fibers is also analyzed through self-waveguided emission. These results open
interesting perspectives for realizing complex and ordered architectures by
light-emitting nanofibers, such as photonic circuits, and for the precise
positioning and integration of conjugated polymer fibers into light-emitting
devices.Comment: 11 pages, 6 figures Nanoscale, 201
The Italian hospital system
Over the last decade two reforms have affected the Italian hospital system, one introducing market mechanisms, the other concerning the tools of planning and expense control assigned to the regional governments. The paper summarizes these institutional changes and describes the evolution of the structure and the activity of the hospital system, with a focus on the differences between regions. It highlights the following: (1) the reduction in the number of hospitals and hospital beds and the gap between regions in terms of hospital beds per capita; (2) the growth in personnel compared with the number of hospital beds; (3) the stationarity of admissions since the end of the nineties and the growth in the share of those in day hospital; (4) the greater number of admissions in southern regions, especially for inappropriate or less complex treatment, and the high level of migration towards northern hospitals; (5) with reference to costs, increasing returns to scale up to a given hospital size, which is larger, the more complex the courses of treatment provided; (6) the differences between regions in costs which are affected by the size of facilities and their type of specialization.hospitals, sanitary system, hospital performances, hospital costs
Penalized Orthogonal Iteration for Sparse Estimation of Generalized Eigenvalue Problem
We propose a new algorithm for sparse estimation of eigenvectors in
generalized eigenvalue problems (GEP). The GEP arises in a number of modern
data-analytic situations and statistical methods, including principal component
analysis (PCA), multiclass linear discriminant analysis (LDA), canonical
correlation analysis (CCA), sufficient dimension reduction (SDR) and invariant
co-ordinate selection. We propose to modify the standard generalized orthogonal
iteration with a sparsity-inducing penalty for the eigenvectors. To achieve
this goal, we generalize the equation-solving step of orthogonal iteration to a
penalized convex optimization problem. The resulting algorithm, called
penalized orthogonal iteration, provides accurate estimation of the true
eigenspace, when it is sparse. Also proposed is a computationally more
efficient alternative, which works well for PCA and LDA problems. Numerical
studies reveal that the proposed algorithms are competitive, and that our
tuning procedure works well. We demonstrate applications of the proposed
algorithm to obtain sparse estimates for PCA, multiclass LDA, CCA and SDR.
Supplementary materials are available online
«Kannst du’s wohl mit geschloßnen Augen denken?». La semantica del vedere nelle traduzioni italiane della «Pentesilea» di Kleist: [«Can you still visualize it when you shut your eyes?». The semantics of seeing in the Italian translations of Kleist’s «Penthesilea»]
Starting from the centrality of the part played by the eye in Kleist’s work and, in particular, in Penthesilea, I propose to investigate how this field emerges from the Italian translations of the work. Supported by the instruments of Textsemantik (Greimas) and Texttheatralität (Poschmann) and following the comparative method (Utz), particularly significant passages from the tragedy are analysed which, in the light of this theme, pose interesting questions related to isotopy and can illuminate the differences between the translations
Dalle Baccanti all’Ibiza-Gate. «Schwarzwasser» di Elfriede Jelinek: [From the Bacchae to the Ibiza-Gate. Elfriede Jelinek’s «Schwarzwasser»]
Taking studies on deconstruction, performance theories, and pragmatics as my point of departure, I investigate Elfriede Jelinek’s last political play Schwarzwasser (2020), where the so-called Ibiza-gate – which in 2018 involved the former Vice Chancellor of Austria – is represented. In her interpretation, Jelinek refers to René Girard’s Violence and the Sacred and Euripides’ Bacchae in an intertextual dialogue. This contribution aims to show how and why Jelinek recalls and employs The Bacchae in her play and to establish a connection between the political function of Greek theatre and Jelinek’s view of Austrian populism
Characterization of gas phase iron phthalocyanine with X-ray photoelectron and absorption spectroscopies
Despite the numerous studies dedicated to phthalocyanine molecules adsorbed on surfaces, in monolayer or thin film, very few works have been focused on the characterization of vapors of these molecules. In this article we present the C 1s, N 1s and Fe 2p photoemission results as well as N K-edge X-ray absorption data of iron phthalocyanine (FePc) in gas phase. Presented comparison of X-ray photoelectron spectroscopy and X-ray absorption spectroscopy spectra of FePc films show a great similarity with the gas phase results, con- firming the molecular character of thick films. The Fe 2p photoemission spectrum of the gas phase FePc, shown for the first time, can be considered as a fingerprint of the Fe(II) ionic state of the central metal of the iron phthalocyanine. The performed multiplet calculations for describing the Fe 2p XP spectrum indicate 3 Eg (a1g 2 eg 3 b2g 1 ) state as the most probable ground state for thick film of iron phthalocyanine
Atomic contributions to the valence band photoelectron spectra of metal-free, iron and manganese phthalocyanines
The present work reports a photoelectron spectroscopy study of the low-energy region of the valence band of metal-free phthalocyanine (H2Pc) compared with those of iron phthalocyanine (FePc) and manganese phthalocyanine (MnPc). Density Functional Theory calculations have been used to resolve the atomic orbital composition of the valence spectra of all the phthalocyanines (Pcs) analyzed in this study. Moreover we show how the atomic character of the Highest Occupied Molecular Orbital (HOMO) is reflected on the outermost valence band binding energy region. The intensity related to the C 2p contributions, resulting in the HOMO for H2Pc and FePc and in the HOMO-1 for MnPc as described by the theoretical predictions is in very good agreement with the experimental results. The DFT simulations, discerning the atomic contribution to the density of states, indicate how the central metal atom interacts with the C and N atoms of the molecule, giving rise to different partial and total density of states for these three different Pc molecules
Mutual Guarantee Institutions (MGIs) and small business credit during the crisis
The recent economic and financial crisis has drawn attention to how mutual guarantee institutions (MGIs) facilitate small and medium enterprises in accessing bank financing. The aim of this paper is twofold. First, we describe the structural features of the Italian market for mutual guarantees and its significance for small business credit. To this end, we use extensive databases (the Central Credit Register and the Central Balance Sheet Register) as well as specific surveys, which allow us to fill information gaps about this industry and to quantify regional diversity. Second, we investigate whether MGIs’ support to small firms continued to be effective in 2008-09, when credit constraints to Italian firms peaked. We find that MGIs played a role in avoiding a break-up in credit flows to affiliated firms, which also benefited from a lower cost of credit. However, this came at the cost of a deterioration in credit quality, which was more intense for customers with guarantees from MGIs.microfinance, peer monitoring, small business finance
Current millennium biotechniques for biomedical research on parasites and host-parasite interactions
The development of biotechnology in the last three decades has generated the feeling that the newest scientific achievements will deliver high standard quality of life through abundance of food and means for successfully combating diseases. Where the new biotechnologies give access to genetic information, there is a common belief that physiological and pathological processes result from subtle modifications of gene expression. Trustfully, modern genetics has produced genetic maps, physical maps and complete nucleotide sequences from 141 viruses, 51 organelles, two eubacteria, one archeon and one eukaryote (Saccharomices cerevisiae). In addition, during the Centennial Commemoration of the Oswaldo Cruz Institute the nearly complete human genome map was proudly announced, whereas the latest Brazilian key stone contribution to science was the publication of the Shillela fastidiosa genomic sequence highlythed on a Nature cover issue. There exists a belief among the populace that further scientific accomplishments will rapidly lead to new drugs and methodological approaches to cure genetic diseases and other incurable ailments. Yet, much evidence has been accumulated, showing that a large information gap exists between the knowledge of genome sequence and our knowledge of genome function. Now that many genome maps are available, people wish to know what are we going to do with them. Certainly, all these scientific accomplishments will shed light on many more secrets of life. Nevertheless, parsimony in the weekly announcements of promising scientific achievements is necessary. We also need many more creative experimental biologists to discover new, as yet un-envisaged biotechnological approaches, and the basic resource needed for carrying out mile stone research necessary for leading us to that "promised land"often proclaimed by the mass media
Near-infrared quantum dots labelled with a tumor selective tetrabranched peptide for in vivo imaging
Near-infrared quantum dots (NIR QDs) are a new class of fluorescent labels with excellent bioimaging features, such as high fluorescence intensity, good fluorescence stability, sufficient electron density, and strong tissue-penetrating ability. For all such features, NIR QDs have great potential for early cancer diagnosis, in vivo tumor imaging and high resolution electron microscopy studies on cancer cells
- …
