1,721,000 research outputs found
ENVIRONMENTAL DNA IN HONEY: GENOMIC TOOLS FOR ENTOMOLOGICAL AUTHENTICATION OF THIS PRODUCT.
No full textHoney is one of the most commonly frauded food products, with the most frequent frauds involving adulteration and mislabeling of its origin. The entomological origin of honey can be considered from two perspectives: i) the subspecies of Apis mellifera that produced the honey; and ii) the footprints derived from plant-suckling insects that produce honeydew, which are always present in authentic honey. Identifying the A. mellifera subspecies provides an important link to boost the conservation and integrity of honeybee populations and also offer indirect information on the geographic origin of the honey, based on the natural distribution of the different subspecies.
Plant-suckling insects belonging to the Rhynchota order provide multidimensional information related to the plant origin of honeydew, based on the botanical specialization of these plant parasites, indirectly indicating the geographic origin of the honey. To identify the honey bee subspecies, we set up assays to analyse DNA extracted from honey that targeted regions of the A. mellifera mitochondrial DNA (mtDNA). These regions are informative to distinguishing different subspecies carrying the mtDNA lineages A (e.g. A. m. siciliana) and M (e.g. A. m. mellifera), as well haplotypes C1 (A. m. ligustica) and C2 (A. m. carnica). Another assay was designed to genotype approximately100 subspecies-informative honey bee single nucleotide polymorphisms (SNPs) using DNA extracted from honey and a genotyping-by-sequencing approach. For identifying plantsuckling insects, we designed a targeted metabarcoding assay based on two conserved regions of Rhynchota mtDNA using a next generation sequencing approach, along with bioinformatic pipelines to interpret sequenced reads and assign them to Rhynchota families. These approaches were applied to more than 150 honey samples, revealing that these methods are highly informative for authenticating the honey based on their entomological origin
GENETIC VARIABILITY WITHIN AND ACROSS SEA CUCUMBER POPULATIONS FROM DIFFERENT MEDITERRANEAN SITES
No full textSea cucumbers (class Holothuroidea, phylum Echinodermata), also named holothurians, are widespread all over the world seas and play an important ecological role for their bioturbation and alkalinization activities of the seabed. These species are also considered economically relevant for Asian luxury food (e.g. trepang) and traditional medicine markets, as well as for the production of pharmaceutical and cosmetic bioactive compounds. Their economic relevance has caused an overexploitation of holothurians to supply these specific markets, especially in the Mediterranean area where the excessive fishing is a quite recent phenomenon. The massive withdrawal of sea cucumbers from the Mediterranean Sea (hundreds of tons of holothurians per year) has been demonstrated to have a negative impact on the marine benthonic ecosystem and caused a biodiversity loss among populations and in some places their complete extinction. For these reasons, few initiatives are recently evaluating sea cucumbers as novel aquaculture species. The aim of this study was to evaluate the level of genetic diversity within two Mediterranean sea cucumber species, Holothuria polii and Holothuria tubulosa, across different Mediterranean areas, before considering the implementation of conservation actions and as a first step in establishing cultivated stock populations. We analyzed portions of cox1 and 16S mitochondrial gene sequences because of their informativeness both for species identification across the genus Holothuria and for genetic variability estimations within and across different populations
Variability in genes affecting morphological traits in the Greek black pig breed and conservation of this genetic resource
No full textAutochthonous pig breeds of Mediterranean regions are genetic resources that are well adapted to the harsh and hot environmental conditions of this area. These breeds might represent important reservoirs of genetic variability that could be exploited in the context of climate change. The Greek black pig is a local breed mainly raised in Thessaly and Macedonia regions whose origin goes back to the ancient times. The desertification of Greek countryside occurred between 1955 and 1960 and the migration of the inhabitants to large urban centers caused a harsh extinction of this breed and the import of well-known foreign pigs. About 20 years ago, a conservation program for this breed started from only ~100 animals found in the whole country. Pigs of this breed are characterized by a solid black coat colour phenotype. The current population is constituted by a few small nuclei of pigs bred in extensive or semi extensive production systems where genetic hybridization with wild boars could frequently occur. This breed has not been characterized at the molecular genetic level yet. In this study, we analysed polymorphisms in five genes affecting coat colour and colour patterns (MC1R and KIT), growth rate and lean meat/fat deposition (IGF2) and vertebral and teat number (NR6A1 and VRTN) in a total of 59 Greek black pigs (7 boars and 52 sows). At the MC1R gene, the most frequent allele was the European dominant black ED2 (0.70). Other alleles at this gene were identified but always in heterozygous state with the dominant allele that might confer the characteristic black coat colour of the analysed animals. A new ED2 variant was also identified in three pigs. We also detected the presence of the KIT gene polymorphism associated with the belted phenotype in two animals and the KIT gene duplication in one pig. At the IGF2 gene, allele g.3072A had a frequency of 0.86. The domestic allele g.265347265T of the NR6A1 gene was the most frequent (0.84). The wild type C allele at this polymorphic site was detected in 11 pigs. Finally, the SINE insertion of 291 bp in the VRTN gene, associated with an increased number of vertebrae and teats, had a frequency equal to 0.45. The genetic variability detected in the five investigated genes can confirm, to some extent, the occurrence of introgression events with both wild boars and other pig populations, further strengthening the need to develop appropriate conservation programs of this autochthonous Greek pig breed
Taking advantage from phenotype variability in a local animal genetic resource: identification of genomic regions associated with the hairless phenotype in Casertana pigs
Full text link<p><em>his is the pre-peer reviewed version of the following article: “</em><em>Taking advantage from phenotype variability in a local animal genetic resource: identification of genomic regions associated with the hairless phenotype in Casertana pigs” by Giuseppina Schiavo, Francesca Bertolini, Valerio Joe Utzeri, Anisa Ribani, Claudia Geraci, Laura Santoro, Cristina Óvilo, Ana I. Fernández, Maurizio Gallo and Luca Fontanesi,</em><em> which has been published in final form at </em><em><a href="https://doi.org/10.1111/age.12665"><strong>https://doi.org/10.1111/age.12665</strong></a><strong> </strong></em><em>. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."</em></p>
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
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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