1,720,992 research outputs found
Tetrapod footprints and associated biota: new evidences from the Upper Carboniferous of Southwestern Sardinia, Italy
No full textSeveral tetrapod footprints have been recently found in the U. Carboniferous fluvio-lacustrine
deposits of the San Giorgio Basin (Iglesias, SW Sardinia). They represent, together with the
ones figured by Fondi (1980), the earliest evidence of vertebrate tracks recorded in Italy. The
studied section, about 33 m thick, is located 2.5 km SSW of Iglesias and is entirely assigned to
the Westphalian-Stephanian. The specimens originate from the yellow-grey dolomitic siltstone
interval of the middle unit (unit B, Del Rio et al., 2002). The collected tetrapod footprints are
on eight slabs and are chiefly preserved as casts of three manus-pes couples and by other
isolated footprints which, for their different shape and size, are referable to three distinct
morphotypes that differ from those assigned to Salichnium (Saurichnites) heringi (Geinitz,
1885) by Fondi (1980). Additional ichnofossils are represented by tiny arthropod tracks and
trails. The biota is largely dominated by diversified plant remains and palynomophs, while
body fossils are represented by an exquisitely preserved Anthracomartid spider and a blattoid
wing. (Del Rio et al., 2002, and cited references). These findings add new data about the U.
Carboniferous of Sardinia and suggest an unexpected faunal diversity which may support more accurate age bracketing and correlations
An experimental approach to improving the teaching-learning process in the geosciences
No full textHow can the teaching-learning process in the field of Geosciences be made more effective? Geosciences are
difficult disciplines, because of their complexity and articulation, and this makes the teaching – learning process
challenging. In order to implement an effective didactic approach teachers should have a solid geological
background that allows them to structure effective activities characterised by inductive approach, innovation
and engagement. Furthemore, most teachers don’t dedicate the right amount of time to the Geosciences, and
the deductive approach to teaching scientific disciplines is widely used. In order to overcome these difficulties
we have designed an instructional model based on the literature data (Hoffman & Ritchie, 1998; Bybee, 2014;
Ambrose et al., 2017) on how we learn, that can be used with different inductive methodologies and for all
type of topics. The model has been applied in the framework of the PLS/PNRR project in two different high
schools in Sicily and has been proposed to the Lyceum students from the third to the fifth year. In this context
the pathway aims to guide students towards discovery by investigating the causes, evidences and effects of
Climate Change. As detectives, the students collect “clues” through real data, observations, tools and use
investigative techniques that allow them to piece together the current complex climatic process in its general
aspects. The objectives are to develop knowledge, skills and competences in the Geosciences and the way
Geoscientists study the Earth. This is important to acquire Geosciences Literacy and to educate citizens who
make conscientious and sustainable decisions for our planet. The path consists of four activities building on
inquiry-based learning, each addressing an aspect of the Global Climate Change. For each activity a different
methodology which place the student at the centre of the didactic action in order to promote the construction
of learning has been used. Each activity is included in the instructional model that is developed in 3 phases:
preparation, construction and evaluation. In order to explain this framework, we will present one of the
four activities, according to the DGBL methodology, regarding the main cause of Global Climate Change.
The students are guided step by step in the learning process, and they are given a “Pre-Test”, a “Post-Test”
and a metacognition survey. The Pre-Post Tests are designed to evaluated the success of the activity and
its effectiveness in developing the Geosciences Literacy, while the metacognition questionnaire is structured
to assess the students’ satisfaction with the activity and to make them aware of their cognitive path, and
preconceptions and misconceptions. The data obtained shows that there has been an improvement in skills and
knowledge acquisition. Furthemore, an improvement of competences development in Geosciences Literacy
and consciousness of what it means to be a Geoscientist has been recorded
Method for assessing the coastal vulnerability to erosion and flooding at the physiographic unit scale
Full text linkThe Intergovernmental Panel on Climate Change foresees a significant global sea-level rise (SLR) during the 21st century, which will cause an increase in coastal vulnerability (CV) to erosion and flooding. CV can be estimated at various scales, both in space (from national to local) and time (from tens to hundreds of years). However, flooding and erosional scenarios need to be calculated at the physiographic unit (P.U.) and on a decadal scale to plan strategies for defending communities living in the coastal areas and to protect critical infrastructures and natural habitats. We present preliminary results of a study for assessing the coastal vulnerability to erosion and flooding at the P.U. scale and on the ten-year time scale. This study is based on the analysis of natural marine nearshore factors (e.g., waves, currents) that control the sediment transport and flooding. The method consists of assessing how these factors control the phenomena of erosion and flooding under the influence of the SLR. We have performed two-dimensional models of wave propagation, sediment transport and morphological changes in the nearshore area and sand/gravel beaches using XBeach model. We have integrated grain-size data, bathymetry, meteorological and wave data. The latter derive from the DICCA hindcast database. For testing the method, 18 P.U. were chosen in the coastal zone between Capo Mongerbino and Cefalù (northern Sicily). This area is ~70 km long and is characterized by rocky and low sand/gravel beaches. About 37% of the coastal perimeter suffers from important erosive phenomena resulting in coastal regression with rates that in some cases exceed the value of 1 m/year (Regione Siciliana - Assessorato Territorio E Ambiente, 2006). Moreover, the coasts are characterized by different orientations and, thus, it is possible to test the influence of different exposure to wind and waves. The expected result is a map of CV to erosion and flooding at the physiographic unit scale and on a decadal scale. This study will help to better understand the natural near-shore processes controlling the CV
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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