1,721,014 research outputs found
Valorization of Olive By-Products: Innovative Strategies for Their Production, Treatment and Characterization
Full text link: Presently, olive oil production signifies a valuable economic income for Mediterranean countries, where approximately 98% of the world's production is established [...]
Editorial to the special issue “lipidomics and neurodegenerative diseases”
Full text linkThe contribution of dysregulation of lipid signaling and metabolism to neurodegenerative diseases including Alzheimer’s and Parkinson’s is the focus of this special issue. Here, the matter of three reviews and one research article is summarized
Aniline/a-cyano-4-hydroxycinnamic acid is a highly versatile ionic liquid for matrix-assisted laser desorption/ionization mass spectrometry
No full textThe performance of a matrix-assisted laser desorption/ionization (MALDI) ionic liquid matrix (ILM) consisting of alpha-cyano-4-hydroxycinnamic acid (CHCA) and aniline (ANI) was evaluated to assess whether it could offer possible advantages over conventional matrices. Ultraviolet (UV), Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) and laser desorption/ionization mass spectrometry (LDI-MS) experiments were carried out with the aim of confirming the structure of the ANI-CHCA ILM. Different model analytes such as amino acids, peptides, proteins, lipids, phospholipids, synthetic polymers, and sugars were tested. Mass spectra with similar or improved signal-to-noise (S/N) ratio (compared to CHCA) were invariably obtained demonstrating the potential of this ILM as a general purpose matrix. Furthermore, protein identification by peptide mass fingerprinting (PMF) and database search was facilitated compared to CHCA since higher scores and increased sequence coverage were observed. Finally, a complex lipid mixture (i.e. a raw extract of a milk sample) analysed by MALDI-MS showed improved S/N ratio, a reduced chemical noise and a limited formation of matrix-clusters
X-ray photoelectron spectroscopy characterization of poly(2,3-diaminophenazine) films electrosynthesised on platinum
No full text
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
Detection of hazelnut oil in extra-virgin olive oil by analysis of polar components by micro-solid phase extraction based on hydrophilic liquid chromatography and MALDI-ToF mass spectrometry
No full textThe oil polar fraction may have a great potential for the characterization of vegetable oils and for the individuation of
adulterations. In particular, adulteration of extra-virgin olive oil (EVOO) with hazelnut oil (HO) is one of the most difficult
ones to detect due to the similar composition as regards triacylglycerol, total sterol and fatty acid profile. A new micro-solid
phase extraction (μ-SPE) procedure based on hydrophilic liquid chromatography (HILIC) micro-columns was developed for the
selective extraction and enrichment of polar compounds from EVOO and HO beforematrix-assisted laser desorption ionization
time-of-flight mass spectrometry (MALDI-ToF-MS) analysis. The method permits a simple and fast qualitative analysis of the
polar fraction of the oils under study; furthermore, somepeaks (such as them/z ions 496.39, 520.46 and 522.47) were found tobe
present only inHO, indicating that they could be diagnostic for the presence ofHOin EVOO. In order to verify the potential of the
method for the individuation of this adulteration,EVOOwas progressively adulteratedwith variable quantities ofHO, subjected
to the HILIC enrichment and finally to MALDI-ToF-MS analysis; the detection of adulteration was possible up to the level of
5%. Eventually, diagnostic polar compoundswere identified as lysophosphatidylcholine (LPC) (16 : 0/0 : 0), LPC (18 : 2/0 : 0), LPC
(18 : 1/0 : 0) by means of capillary liquid chromatography-electrospray ionization-quadrupole-ToF-MS (CapLC-ESI-Q-ToF-MS)
analysis
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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