1,721,298 research outputs found
Neighborhood based computational approaches for the prediction of lncRNA-disease associations
Full text linkMotivation: Long non-coding RNAs (lncRNAs) are a class of molecules involved in important biological processes. Extensive efforts have been provided to get deeper understanding of disease mechanisms at the lncRNA level, guiding towards the detection of biomarkers for disease diagnosis, treatment, prognosis and prevention. Unfortunately, due to costs and time complexity, the number of possible disease-related lncRNAs verified by traditional biological experiments is very limited. Computational approaches for the prediction of disease-lncRNA associations allow to identify the most promising candidates to be verified in laboratory, reducing costs and time consuming. Results: We propose novel approaches for the prediction of lncRNA-disease associations, all sharing the idea of exploring associations among lncRNAs, other intermediate molecules (e.g., miRNAs) and diseases, suitably represented by tripartite graphs. Indeed, while only a few lncRNA-disease associations are still known, plenty of interactions between lncRNAs and other molecules, as well as associations of the latters with diseases, are available. A first approach presented here, NGH, relies on neighborhood analysis performed on a tripartite graph, built upon lncRNAs, miRNAs and diseases. A second approach (CF) relies on collaborative filtering; a third approach (NGH-CF) is obtained boosting NGH by collaborative filtering. The proposed approaches have been validated on both synthetic and real data, and compared against other methods from the literature. It results that neighborhood analysis allows to outperform competitors, and when it is combined with collaborative filtering the prediction accuracy further improves, scoring a value of AUC equal to 0966
Systematics of the genus Avena L.: a preliminary work on the polymorphism of Rubisco
No full textIn this work we have adopted the combination of two methods for the purification of Ribulose-1,5-bisphosphate carboxylase/oxygenase to study the behaviour of pure Rubisco-holoenzyme in Native-PAGE and in SDS-PAGE, of some species of the genus Avena L. with different ploidy levels and genome types. This study demonstrates that differences exist in the charge of the holoenzyme but not in the molecular weight of the subunits, in particular, the diploid with CC-genome is very different from the other diploids (AA-genome) and tetraploids (AACC-genome and AABB-genome) under study
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
Valores psicossociais como metassistema: representações sociais de mulher cigana entre brasileiros
Full text linkRESUMO (PORTOGHESE) A partir do paradigma das três fases da Teoria das Representações Sociais, o estudo teve como objetivo analisar como as representações sociais de mulher cigana se ancoram nos valores psicossociais. Participaram do estudo 318 sujeitos não ciganos, de nacionalidade brasileira, com idades entre 17 e 54 anos (M=22.4; DP=6,17). A coleta dos dados foi realizada por meio da aplicação de questionários em instituições de ensino superior, a partir de instrumento constituído pelos seguintes tópicos de informação: dados sócio-demográficos, técnica de associação livre para o termo indutor mulher cigana e valores psicossociais autoatribuídos. O tratamento dos dados foi realizado por meio da análise fatorial de correspondência (τ= 14.03, IEF1 = 4.02, IEF2 = 3.62) e da análise de cluster, procedida com o auxílio do software SPAD-T. Os resultados indicaram associação entre os valores religiosos (Cluster 2) e a imagem mística da cigana como vidente (V-test = 2.6), os pósmaterialistas (Cluster1: Pós-materialistas sociais/V-test = -2.6; e Cluster 3: Pós-materialistas individuais e profissionais/ V-test = -3.2) relacionados à ideia da dança e da alegria, enquanto os materialistas e hedonistas representaram a mulher cigana tanto a partir da imagem da sedução quanto da trapaça (V-test = -4.4). Discute-se a ancoragem psicossocial por meio dos valores como recurso à análise do processo integrado sistema-metassistema no campo de estudo das representações sociais.From the paradigm of the three phases of Theory of Social Representations, the study had as objective to analyze how the social representations of gypsy women anchor themselves in the psychosocial values. 318 non-Roma subjects of Brazilian nationality, aged between 17 and 54 years (M = 22.4; SD = 6.17) participated in the study. Data collection was carried out through the application of questionnaires in higher education institutions, based on an instrument consisting of the following information topics: Socio-demographic data, free association technique for the term gypsy woman inducer and self-attributed psychosocial values. The data were processed using the factorial matching analysis (τ = 14.03, IEF1 = 4.02, IEF2 = 3.62) and the cluster analysis, using SPAD-T software. The results indicated an association between religious values (Cluster 2) and the mystical image of the gypsy as a seer (V-test = 2.6), the post-materialists (Cluster1: Post-materialists social/V-test = -2.6;: Individual and professional post-materialists/V-test = -3.2) related to the idea of dance and joy, while materialists and hedonists represented the gypsy woman both from the image of seduction and cheating (V-test = -4.4 ). Psychosocial anchoring is discussed through the values as a resource to the analysis of the integrated system-metasystem process in the field of study of social representations
Assessing the structure of protic ionic liquids based on triethylammonium and organic acid anions
Full text linkWe present a computational analysis of the short-range structure of three protic ionic liquids based on strong organic acids: trifluoracetate, methanesulfonate, and triflate of triethylammonium. Accurate ab initio computations carried out on the gas-phase dimers show that the protonation of triethylamine is spontaneous. We have identified the anion-cation binding motif that is due to the presence of a strong hydrogen bond and to electrostatic interactions. The strength of the hydrogen bond and the magnitude of the binding energy decrease in the order trifluoroacetate ≳ methanesulfonate > triflate. The corresponding simulations of the bulk phases, obtained using a semiempirical evaluation of the interatomic forces, reveal that on short timescales, the state of the three liquids remains highly ionized and that the gas-phase cation-/anion-binding motif is preserved while no other peculiar structural features seem to emerge
Prediction of User-Brand Associations Based on Sentiment Analysis
Full text linkFinding the right users to be chosen as targets for advertising campaigns is not a trivial task, and it may allow important commercial advantages. A novel approach is presented here for the recommendation of new possible consumers to brands interested in distributing advertising campaigns, ranked according to the “compatibility” between users and brands. A database containing both descriptions associated with different brands, and textual information about users' opinions on different topics, is required in input. Then, sentiment analysis techniques are applied to measure to what extent the users match with the brands, based on the texts associated with their opinions. The approach has been tested on both synthetic and real datasets, and with two different formulations, showing promising results in all the considered experiments
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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