1,721,057 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Integrated photonics in quantum technologies
Get PDFQuantum information processing is nowadays an established branch of quantum mechanics applications. Recent results in different areas, ranging from communications to computing, show that quantum technologies are advancing towards being mature platforms with substantial advantages over traditional classical protocols. Quantum optics and photonic apparatuses are one of the best candidates for the realization of quantum processors. In this context, integrated photonic technologies are essential components towards miniaturisation of such complex optical systems. Integrated optical devices enabled an important improvement in the level of complexity in the generation and processing of quantum states of light. This review aims at providing an exhaustive framework of the advances of integrated quantum photonic platforms, for what concerns the integration of sources, manipulation, and detectors, as well as the contributions in quantum computing, cryptography and simulations
Transverse and Quantum Localization of Light: A Review on Theory and Experiments
No full textAnderson localization is an interference effect yielding a drastic reduction of diffusion-including complete hindrance-of wave packets such as sound, electromagnetic waves, and particle wave functions in the presence of strong disorder. In optics, this effect has been observed and demonstrated unquestionably only in dimensionally reduced systems. In particular, transverse localization (TL) occurs in optical fibers, which are disordered orthogonal to and translationally invariant along the propagation direction. The resonant and tube-shaped localized states act as micro-fiber-like single-mode transmission channels. Since the proposal of the first TL models in the early eighties, the fabrication technology and experimental probing techniques took giant steps forwards: TL has been observed in photo-refractive crystals, in plastic optical fibers, and also in glassy platforms, while employing direct laser writing is now possible to tailor and "design" disorder. This review covers all these aspects that are today making TL closer to applications such as quantum communication or image transport. We first discuss nonlinear optical phenomena in the TL regime, enabling steering of optical communication channels. We further report on an experiment testing the traditional, approximate way of introducing disorder into Maxwell's equations for the description of TL. We find that it does not agree with our findings for the average localization length. We present a new theory, which does not involve an approximation and which agrees with our findings. Finally, we report on some quantum aspects, showing how a single-photon state can be localized in some of its inner degrees of freedom and how quantum phenomena can be employed to secure a quantum communication channel
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Perspectives and recent progress of genome-wide association studies (GWAS) in fruits
No full textBackground: Earlier next-generation sequencing technologies are being vastly used to explore, administer, and investigate the gene space with accurate profiling of nucleotide variations in the germplasm. OVERVIEW AND PROGRESS: Recently, novel advancements in high-throughput sequencing technologies allow a genotyping-by-sequencing approach that has opened up new horizons for extensive genotyping exploiting single-nucleotide-polymorphisms (SNPs). This method acts as a bridge to support and minimize a genotype to phenotype gap allowing genetic selection at the genome-wide level, named genomic selection that could facilitate the selection of traits also in the pomology sector. In addition to this, genome-wide genotyping is a prerequisite for genome-wide association studies that have been used successfully to discover the genes, which control polygenic traits including the genetic loci, associated with the trait of interest in fruit crops.
Aims and prospects: This review article emphasizes the role of genome-wide approaches to unlock and explore the genetic potential along with the detection of SNPs affecting the phenotype of fruit crops and highlights the prospects of genome-wide association studies in fruits.
Keywords: Fruits; Genome-wide association studies (GWAS); Genomic selection (GS); Genotyping-by-sequencing (GBS); Next-generation sequencing (NGS); Single-nucleotide polymorphisms (SNPs)
Origin of the genome editing systems: application for crop improvement
No full textIn the last years, genome editing technologies led to a new era of genome engineering, enabling an effective, precise, and rapid engineering of the plant genomes. Four types of engineered nucleases are used for genome editing: engineered homing endonucleases/meganucleases (EMNs), zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and CRISPR (clustered regularly interspaced short palindromic repeats)/Cas (CRISPR-associated). All these nucleases have one thing in common: to induce double-strand breaks (DSBs) at definite genomic loci. DSB activates the DNA repair mechanisms through the recruitment of DNA repair factors by the cell, that can act in one of two repair pathways: homologous-direct repair (HDR) or non-homologous end-joining (NHEJ). The most common pathway used to repair DSBs in plants (NHEJ) is more mutagenic than the other alternative pathway (HDR). The development of CRISPR/Cas systems has generated a genome editing revolution in plant genetics and breeding. In the present review, the history of CRISPR/Cas methods is reported. Thereafter, the advances in genome editing technologies using CRISPR/Cas9 developed rapidly, with base editing systems for transition substitution using a combination of Cas9 nickase and either cytosine or adenosine deaminase. Moreover, technologies for gene targeting and prime editing systems using DNA or RNA as donors have also been developed. Successful examples where CRISPR/Cas approaches have been used to improve the biotic and abiotic stress tolerance, and traits related to yield and plant architecture have been discussed
Use of Ty1/Copia retrotransposons to study genetic diversity in olive (Olea europaea L.) cultivars.
No full textUse of Ty1/Copia retrotransposons to study genetic diversity in olive (Olea europaea L.) cultivars
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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