1,721,034 research outputs found
Changes in periodontal ligament (PDL) by orthodontic forces: a micro-raman analysis of amide I and lipid contribution.
No full textChanges induces in periodontal ligament (PDL) by othodontic forces: a micro-raman analisys of amide I and lipid contributions.
No full textAnalisi delle variazioni indotte nel legamento parodontale (PDL) da forze ortodontica mediante micro-spettroscopia raman: uno studio preliminare.
No full textWavelet data processing of micro-Raman spectra of biological samples
No full textA wavelet multi-component decomposition algorithm is proposed for
processing data from micro-Raman spectroscopy (μ-RS) of biological
tissue. The μ-RS has been recently recognized as a promising tool for the
biopsy test and in vivo diagnosis of degenerative human tissue pathologies,
due to the high chemical and structural information contents of this
spectroscopic technique. However, measurements of biological tissues are
usually hampered by typically low-level signals and by the presence of noise
and background components caused by light diffusion or fluorescence
processes. In order to overcome these problems, a numerical method based
on discrete wavelet transform is used for the analysis of data from μ-RS
measurements performed in vitro on animal (pig and chicken) tissue
samples and, in a preliminary form, on human skin and oral tissue biopsy
from normal subjects. Visible light μ-RS was performed using a He–Ne
laser and a monochromator with a liquid nitrogen cooled charge coupled
device equipped with a grating of 1800 grooves mm−1. The validity of the
proposed data procedure has been tested on the well-characterized Raman
spectra of reference acetylsalicylic acid samples
Preliminary results on tunnel junctions on YBCO bulk with an artificial barrier
No full textYBCO-bulk based tunnel junctions employing a cadmium sulphide artificial barrier have been fabricated. Preliminary results on the role played by the CdS film thickness and different YBCO surface processing are discussed. dc Josephson effect has been detected in samples with a low tunneling resistance. The dependence of the critical current on the external magnetic field is reported
Monitoring Aging Effects in Graphite Bisulfates by Means of Raman Spectroscopy
No full textGraphite bisulfate (GBS) compounds consist of graphite layers intercalated by HSO4− ions and H2SO4 molecules. Owing to electrostatic interactions with the graphene plane, HSO4− ions cause point defects in the graphite’s crystalline structure, while H2SO4 molecules are free to move via diffusion in the spaces between the adjacent graphite sheets and segregate to form linear defects. In the present work, we report the results of our investigation using Raman spectroscopy on the temporal evolution of such defects on selected GBS samples over 84 months. Two characteristic lengths correlated with the average distance between defects have been estimated and their evolution with aging was investigated. The results show a decrease in the density of point-like defects after aging, regardless of the pristine structural configuration of the GBS samples, revealing a structural instability. This study can provide significant information for the technological development of industrial processes aimed to produce expanded graphite based on GBS precursors, where the aging of GBS is known to influence the efficiency and quality
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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