1,720,999 research outputs found
ENVIRONMENTAL DNA: A POSSIBLE TOOL TO EVALUATE THE VERTEBRATE BIODIVERSITY USING WATER SAMPLES OF THREE SICILIAN LAKE
No full textFreshwater ecosystems play a key role for the biogeochemical cycles and are subject to several anthropic impact that cause a biodiversity loss. Conventional census methods seem to be insufficient and not very convenient for the detection of species. The organisms inhabiting these sites continuously release DNA, called "environmental DNA" (eDNA), through cells, excrement, gametes and/or decomposing material and its evaluation could revolutionize the monitoring of biodiversity (HARPER et al., 2019; SCHENEKAR, 2023). On the other hand, today there are considerable doubts about it: seems to be the non-existence of well-defined protocols which depend on the sampling site, environmental factors and extraction methods; degradation processes are very rapid and the costs of evaluations are very high (many samples are needed in different points). The aim of this study (part of RTDA-PON project) was to fine-tune the sampling and eDNA extraction protocol, reducing the costs and evaluating the potential of this method compared to the conventional methods. Another aim was evaluating the biodiversity of vertebrate in some Sicilian Lake for which until to date no more is known. In this study, the eDNA technique was used for the first time in three Sicilian lakes: Poma Lake, Piana degli Albanesi Lake and Scanzano Lake.The water sampled in each site was filtered and eDNA was extracted using extraction kit. Metabarcoding analysis was performed by IGA Technology Services s.r.l. The results showed the possibility to understand which types of phyla, class, order, family, gender, or species lives in these sites. The species not captured or not sighted using conventional methods were detected thanks to the use of eDNA and vice versa highlighting that the evaluation of eDNA can be useful to evaluate not only aquatic species but also other species that use these sites as a source of supply. Another important result was the possibility to detect DNA of species not typical of freshwater sites highlighting the contamination process. eDNA is a very important tool to evaluate the biodiversity and the health status of the environment, but on the other hand, for a more complete census, it is very important use also other conventional methods at the same times. Our preliminary results showed that eDNA method have the potential to replace the traditional methods of census but it is not yet the time to do it, using both methods is surely the best approach
Suggestive linkage of familial mesial temporal lobe epilepsy to chromosome 3q26
No full textPurpose: To describe the clinical findings in a family with a benign form of mesial temporal lobe epilepsy and to identify the causative genetic factors. Methods: All participants were personally interviewed and underwent neurologic examination. The affected subjects underwent EEG and most of them neuroradiological examinations (MRI). All family members were genotyped with the HumanCytoSNP-12 v1.0 beadchip and linkage analysis was performed with Merlin and Simwalk2 programs. Exome sequencing was performed on HiSeq2000, after exome capture with SureSelect 50Mb kit v2.0. Results: The family had 6 members with temporal lobe epilepsy. Age at seizure onset ranged from 8 to 13 years. Five patients had epigastric auras often associated to oro-alimentary automatic activity, 3 patients presented loss of contact, and 2 experienced secondary generalizations. Febrile seizures occurred in 2 family members, 1 of whom also had temporal lobe epilepsy. EEG showed focal slow waves and epileptic abnormalities on temporal regions in 1 patient and was normal in the other affected individuals. MRI was normal in all temporal lobe epilepsy patients. We performed single nucleotide polymorphism-array linkage analysis of the family and found suggestive evidence of linkage (LOD score = 2.106) to a region on chromosome 3q26. Haplotype reconstruction supported the linkage data and showed that the majority of unaffected family members carried the haplotype at risk. Whole exome sequencing failed to identify pathogenic mutations in genes of the candidate region. Conclusions: Our data suggest the existence of a novel locus for benign familial mesial temporal lobe epilepsy on chromosome 3q26. Our failure to identify pathogenic mutations in genes of this region may be due to limitations of the exome sequencing technology. (C) 2013 Elsevier B.V. All rights reserved
Environmental DNA: The First Snapshot of the Vertebrate Biodiversity in Three Sicilian Lakes
Full text linkFreshwater ecosystems play a key role in global diversity and are subject to a series of anthropic impacts, often leading to biodiversity loss. The organisms inhabiting these sites continuously release DNA into the environment through cells, excrement, gametes and/or decomposing matter; thus, evaluation of this eDNA could revolutionize the monitoring of biodiversity. In this study, environmental DNA metabarcoding was used for the first time in three Sicilian lakes: Lake Poma, Piana degli Albanesi Lake and Lake Scanzano. Results obtained provide the first snapshot of vertebrate biodiversity in these three lakes, where little is known, to provide valuable information useful for creating a baseline of knowledge regarding the biodiversity in these three lakes. Another important result was the detection of marine species, most likely due to some kind of anthropogenic contamination. Environmental DNA is a useful tool to evaluate both biodiversity and the ecological status of the environment; it has the potential to complement traditional methods, and the use of both approaches may offer a more comprehensive understanding of the ecosystem
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
Perturbations in Microbial Communities at Hydrothermal Vents of Panarea Island (Aeolian Islands, Italy)
Full text linkMarine hydrothermal ecosystems represent extreme environments connected to submarine volcanic areas characterized by vents, having high temperatures and particular chemical compositions. The hydrothermal marine system of Panarea, located in one of the seven small islands belonging to the Aeolian Archipelago (southern Tyrrhenian Sea), is characterized by a range of vents exhibiting diverse physical and chemical conditions. We aimed to analyze the microbial community of a peculiar hot spring belonging to the Panarea hydrothermal field, known as “Black Point” (BP), in two separate sampling expeditions (May and August). Our results demonstrated that the chemical–physical variations within this hydrothermal vent, such as temperature fluctuations, mineral content, and hydrothermal fluid dynamics, play a role in shaping the structure and diversity of microbial communities. The differences between the two sampling expeditions suggest that seasonal changes, i.e., in temperature, pH, and redox potential (Eh), could drive microbial community shifts over time
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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