bluuebunny/crossref_metadata_2025_split huggingface dataset:
Similarities and differences in the ilia of Late Cretaceous anurans and urodeles
Authors: Roček Zbyněk , Gardner James D. , Eaton Jeffrey G. , Přikryl Tomáš 
Published: January 2013

AbstractScreen-washing of matrix from 37 Upper Cretaceous microvertebrate localities in southern Utah, USA, yielded a rich sample of anuran disarticulated bones, including nearly 200 ilia. Because the bones are relatively small and delicate and were subject to pre-mortem transport and unavoidable damage when the fossiliferous matrix was collected and processed, none of the recovered ilia retained intact shafts. This means that features such as the form of the anterior end of the shaft and the presence and form of a dorsal crest cannot be used to identify the fossils. Urodele bones also are known from many of the same localities. When anuran and urodele ilia are isolated and missing much of their shafts, they are superficially similar, so it was important to reliably differentiate ilia of the two groups. Here we provide a list and brief descriptions of some of the features that we found useful for distinguishing between anuran and urodele ilia. These features relate to differences between the two groups in muscle attachments, contacts between pelvic bones, and structure of the acetabula. Because all of the features exhibit some variation, we recommend that they be used in combination when trying to distinguish between anuran and urodele ilia.
Paleobiogeography and biodiversity of Late Maastrichtian dinosaurs: how many dinosaur species went extinct at the Cretaceous-Tertiary boundary?
Authors: Le Loeuff Jean 
Published: January 2013

Abstract
The global Late Maastrichtian non-avian dinosaur apparent biodiversity is extensively surveyed for the first time. It amounts to 104 species (including unnamed forms) in 2010. The real biodiversity being obscured by taphonomical biases and the scarcity of the continental fossil record, a species-area relationship is used to estimate it. The results show that several hundreds (between 628 and 1078) non-avian dinosaur species were alive in the Late Maastrichtian, which is almost an order of magnitude above previous estimates. Because of the complex Late Cretaceous palaeobiogeography, discussions about dinosaur extinction should be based on this estimated real global biodiversity, not on the apparent biodiversity of a single area. Given the mean duration of dinosaur genera (7.7 Ma), the presence of so many dinosaur species in the Latest Cretaceous is consistent with the termination of most lineages at the Cretaceous-Tertiary boundary (the Late Maastrichtian sub-stage is 2.8 m.y. long). The Late Maastrichtian dinosaurian biodiversity is therefore consistent with the sudden extinction of the group following the Chicxulub impact.
Late Cretaceous (Maastrichtian) ray-finned fishes from the island of Gavdos, southern Greece, with comments on the evolutionary history of the aulopiform teleost Enchodus
Authors: Cavin Lionel , Alexopoulos Apostolos , Piuz André 
Published: January 2013

AbstractTwo fish fragments from the Middle to Late Maastrichtian of the Island of Gavdos, Greece, are described. One is a caudal portion of an Ichthyodectoidei incertae sedis, which shows some affinities with Saurodon elongatus from the Late Campanian – Early Maastrichtian of Nardo, southern Italy. The other specimen is an isolated skull referred to Enchodus cf. dirus, which is well preserved enough to be included into a phylogenetic analysis of species referred to the genus Enchodus, and subsequently to analyse the biogeograhic signal provided by the cladogram. E. dirus is known in the Late Cretaceous of North America, both in the Western Interior Seaway and on the eastern coast. The occurrence of this lineage is western Tethys and central Tethys is regarded as the result of a vicariant event. Other vicariant events occurred in the Cretaceous between Enchodus species occurring in western and central Tethys respectively. On the other hand, the geographic distribution of several Enchodus species shows ranges extending along North-South axes.
Vertebrate biodiversity of the Deccan volcanic province of India: A review
Authors: Prasad Guntupalli V.R. 
Published: January 2013

AbstractThe Deccan Traps of peninsular India, representing one of the largest flood basalt eruptions on the earth's surface, have been a subject of intensive research in the last three decades because of the attributed link between the Deccan Traps and the Cretaceous-Tertiary boundary mass extinctions. In this context, the biota from the sedimentary beds intercalated with the volcanic flows and underlying the oldest volcanic flow are more important for understanding the faunal diversity and palaeobiogeography of India during the time span of volcanic eruptions. A detailed review of the vertebrate faunal diversity of the Deccan volcanic province is presented here.
Earliest record of the fossil snake Palaeophis from the Paleocene/Eocene boundary in Denmark
Authors: Kristensen Hans Viborg , Cuny Gilles , Rasmussen Arne Redsted , Madsen Henrik 
Published: January 2013

AbstractThe earliest record of Palaeophis ever found in Denmark is here based on vertebrae described from the Paleocene/Eocene Stolleklint Clay of the Isle of Mors (northern Denmark). Although much smaller, they appear quite similar to the Eocene vertebra described from the Fur Formation in the same area, and all belong to the ‘primitive’ grade of Palaeophis species, although a more precise identification cannot be provided at the moment.
Geoemydid turtles from the Late Eocene Maoming basin, southern China
Authors: Claude Julien , Zhang Jiang-Yong , Li Jian-Jun , Mo Jin-You , Kuang Xue-Wen , Tong Haiyan 
Published: January 2013

Abstract
The fossil record of testudinoid turtles of China during the Eocene-Oligocene is poorly documented. The Maoming basin is one of the few Paleogene basin in southern China having yielded a rich turtle fauna including Trionychidae, Carettochelyidae and Geoemydidae (Testudinoidea). Testudinoids were known in this basin by a single, supposed aquatic species, Isometremys lacunaChow and Yeh, 1962. The examination of the new material collected since the first description, and a reexamination of the type material provide additional data on the morphology of that species. In addition, a second geoemydid, Guangdongemys pingi nov gen. nov sp., is described on the basis of shell material. Both species are supposed to be aquatic, and have a probably basal position in the geoemydid phylogeny.
Early Oligocene to Pliocene Colubridae of Europe: a review
Authors: Szyndlar Zbigniew 
Published: January 2013

AbstractThe paper reviews the entire fossil record of the Colubridae coming from the European Early Oligocene (MP21) to late Early Pliocene (MN15) localities. Prior to the end of the Early Miocene, European colubrids were rare and dominated by booid snakes. At the end of the Early Miocene (MN4), the archaic ophidian fauna of Europe was literally flooded by eastern immigrants, principally representatives of the colubroid families Colubridae, Elapidae, and Viperidae. Since then, the Colubridae became a dominant group in snake assemblages, both in Europe and elsewhere. The rich colubrid fauna inhabiting the European continent in the Middle Miocene (MN5 to 7+8) was composed exclusively of extinct species, representing mainly fossil genera, although members of living genera were also quite common. At the beginning of the Late Miocene (MN9), almost all fossil genera became extinct, but living genera were represented exclusively by fossil species. In the late Early Pliocene (MN15), almost all European colubrids were living species. The Late Pliocene (MN16) and Pleistocene colubrid snakes did not differ from those inhabiting Europe today.
Un nouveau genre, Ragesaurus (Squamata, Anguidae, Anguinae), du Pléistocène inférieur des îles Medas (Catalogne, Espagne)
Authors: Bailon Salvador , Auge Marc 
Published: January 2013

Abstract
Ragesaurus n.gen. est un petit Anguinae décrit à partir d'un dentaire presque complet provenant du gisement du Pléistocène inférieur des Iles Medas. Morphologiquement proche des Anguini, il diffère des représentants actuels et fossiles connus des Anguinae par la configuration particulière du foramen alvéolaire antéro-inférieur (limité antéroventralement par un septum osseux) ; par la présence d'un canal de Meckel partiellement entouré par le dentaire et, dans une moindre mesure, par la morphologie des dents médianes.
Growth and Physiological Response of Timothy to Elevated Carbon Dioxide and Temperature under Contrasted Nitrogen Fertilization
Authors: Piva Angela , Bertrand Annick , Bélanger Gilles , Castonguay Yves , Seguin Philippe 
Published: January 2013

ABSTRACTClimate change is expected to affect the growth and metabolism of many economically important plants including timothy (Phleum pratense L.), a major forage grass species in eastern Canada and northern Europe. Our objective was to assess the impacts of predicted increases in CO2 concentration and temperature, under contrasted N fertilization, on timothy biomass, leaf photosynthesis, and nonstructural carbohydrate concentration. Plants were grown in growth chambers under either 400 or 600 μL L−1 of CO2 and at a day/night temperature of either 22/10°C or 25/15°C, and they were fertilized with 0, 60, or 120 kg N ha−1. Two sequential harvests were taken following a 6‐wk establishment period. Elevated CO2 concentration did not affect forage biomass and increased root biomass only at first harvest, but it increased leaf photosynthesis and total soluble sugar concentration mostly when N was not limiting (120 kg N ha−1). Increased temperature reduced forage and total biomass and soluble sugar concentrations at the second harvest under 120 kg N ha−1. Combined increases of temperature and CO2 concentration (600 μL L−1 and 25/15°C) had no effect on biomass yield, but it increased leaf photosynthesis and nonstructural carbohydrates concentration compared to current conditions. Our findings show that predicted future conditions of elevated temperature and CO2 concentration will have little effect on the yield of timothy while their effect on photosynthesis and forage nonstructural concentration will depend on N availability.
Eruption of the permanent maxillary canines in relation to mandibular second molar maturity
Authors: Perinetti Giuseppe , Callovi Marilena , Salgarello Stefano , Biasotto Matteo , Contardo Luca 
Published: January 2013

ABSTRACT

Objective:
To evaluate the timing of spontaneous maxillary canine eruption in relation to stages of mandibular second molar maturation. Potential confounding effects from such factors as age, growth phase, and facial features were also explored.

Subjects and Methods:
A sample of 106 healthy subjects (48 females and 58 males; age range, 9.4–14.3 years) with both permanent maxillary canines during the final phase of intraoral eruption were included. Mandibular second molar maturation (stages E to H) was assessed according to the method of Demirjian. Skeletal maturity was determined using the cervical vertebral maturational (CVM) method. Facial vertical and sagittal relationships were evaluated by recording the Sella-Nasion/mandibular plane (SN/MP) angle and the ANB angle. An ordered multiple logistic regression was run to evaluate adjusted correlation of each parameter with the mandibular second molar maturational stage.

Results:
Overall, the prevalence of the different second molar maturational stages was 36.8%, 37.8%, and 27.4% for stages E, F and G, respectively. According to the regression model, this relation was not influenced by sex, CVM stage, SN/MP angle, and ANB angle.

Conclusions:
Irrespective of sex, growth phase, and facial features, the maturational stage of the mandibular second molar may be a reliable indicator for the timing of spontaneous eruption of the maxillary canine.
Young People and Social Networks: Motivations and Preferred Uses
Authors: Colás-Bravo Pilar , González-Ramírez Teresa , de-Pablos-Pons Juan 
Published: January 2013

This article presents the results of a study on the use of social networks among young Andalusians. The main objectives are to know the uses of social networks, their frequency and the motives behind their use. A questionnaire was used to collect the data. The sample includes 1487 adolescents in Andalusia. The results show that young people, for the most part, consistently used social networks. We identified two motivational aspects in this use: one social and the other psychological. There are not significant gender differences in frequency of use, but rather in the motivations for access. Boys tend to be the more emotional type, while girls were dominated by a more relational motivation. The results show similarities with international researches in environments that vary greatly from the present work. The conclusions suggest the need for future lines of work. This study also identifies the implications of social network uses for active citizenship and participatory training and social integration. These results are also important for the enrichment of dimensions such as social capital development and education.Este artículo presenta los resultados de un estudio sobre la utilización que hacen los jóvenes andaluces de las redes sociales. Los objetivos fundamentales son: conocer los usos preferentes de las redes sociales, su frecuencia y los motivos que les impulsan a su utilización. Además se estudia si existen diferencias de sexo tanto en la frecuencia como en las motivaciones de uso. Se aplica un cuestionario para la recogida de datos. La muestra es de 1.487 adolescentes de Andalucía. Los resultados muestran que los jóvenes en su mayoría usan de manera habitual las redes sociales y se identifican dos vertientes motivacionales en su uso: una social y otra psicológica. No se hallan diferencias significativas entre sexos en cuanto a frecuencia de uso, pero sí en las motivaciones para su acceso. Las de los chicos son de tipo emocional, mientras que en las chicas predomina la motivación de carácter relacional. Los resultados obtenidos muestran coincidencias con investigaciones internacionales realizadas en contextos muy diferentes al presente estudio. En la discusión de resultados se plantean futuras líneas de trabajo, a la vez que se identifican implicaciones que los usos de las redes sociales tienen para la formación e integración social de una ciudadanía activa y participativa, así como para el enriquecimiento de dimensiones como el desarrollo del capital social y la educación.
Youth’s Usage of Leisure Time with Video Games and Social Networks
Authors: Muros-Ruiz Beatriz , Aragón-Carretero Yolanda , Bustos-Jiménez Antonio 
Published: January 2013

The aim of this article is to understand the behaviour of Secondary Education students during their leisure time when using some different virtual spaces. We report a study carried out in a Community Centre offering training and leisure services for youngsters. Due to the large number of technological activities offered, this study paves the way for analysis and reflection about the hidden reasons and motivations young people have to use virtual spaces. We also show the interpretations and reflections of youngsters in their personal relationships and models of cohabitation. Our study likewise approaches the relation that youngsters establish between real and virtual spaces, focusing our attention on the construction of interactions which stems from their personal experiences. For data collection we carried out observations, conversations, analysis of documents and interviews. We analyzed with special interest the meanings that youngsters assign to their experiences in relation with mediatic and civic processes during their leisure time. The results of the study help to know the initiative, motivations and manner of acting that the youngsters of this study have on their ways of socialization in community. Concretely, the aspects allied with the search of pleasure, entertainment, the maintenance of social ties and continuous stimulation uses.Este artículo tiene como finalidad comprender los comportamientos de jóvenes de Educación Secundaria Obli­gatoria durante el tiempo libre en el uso de diferentes entornos virtuales. Presenta un estudio realizado en un centro de servicios comunitarios, formativos y de ocio orientado a la juventud. Debido a la oferta de actividades lúdicas de carácter tecnológico que en este lugar se realiza, el estudio abre vías de análisis y reflexión sobre los planteamientos y las motivaciones en el uso de los entornos virtuales, sobre las interpretaciones y reflexiones de los jóvenes en cuanto a relaciones personales y modelos de convivencia. En el trabajo se realiza una aproximación a la relación que establece la juventud entre el escenario presencial y virtual, centrando la atención en la construcción de interacciones de un modo vivencial. Para la recogida de información se realizaron observaciones, conversaciones, análisis de documentos y entrevistas. Se han analizado con especial interés los sentidos que se atribuían a las experiencias en relación con los procesos mediáticos y cívicos en la ocupación del tiempo libre. Los resultados del trabajo ayudan a conocer los planteamientos, las motivaciones y las conductas que los jóvenes de este estudio tienen sobre sus formas de socialización en red. Concretamente, los aspectos relacionados con la búsqueda del placer, el entretenimiento, el mantenimiento de lazos sociales y la estimulación continua en los usos.
Interactive Youth and Civic Cultures: The Educational, Mediatic and Political Meaning of the 15M
Authors: Hernández-Merayo Elisa , Robles-Vílchez Mª Carmen , Martínez-Rodríguez Juan Bautista 
Published: January 2013

This contribution is justified by the necessity of analyzing the participative content that the interactive youth transmitted in the use of ICTs and social networks in the origin of the social movement of the Spanish Revolution. Our objectives have been focused on proving how young people feel, live and experience the democratic citizenship by means of audiovisual display systems, participating in public open spaces where a better informed digital citizenship is being formed among the technological convergence, hypertextuality and non linearity. We have tried to identify both the educational content of their interactions and implications and the use of audiovisual display systems in their organization as a group. The methodology we have used is the in-depth case study in the days when people occupied public spaces. We collected observations, interviews, information from the social networks (Twitter, Facebook, n-1, Tuenti), news in the media and also information, posters and photographs generated during the occupation by the participants themselves. From this techno-educational point of view we analyze how these young people widen their communicative relationships and get connected on line creating new meanings for educational, social and political issues. The analysis of their speeches shows us a reappropriation of the ICTs by these young people who express and communicate publicly and contributing in this way with new points of view for the citizenship education.Esta aportación se justifica en la necesidad de analizar el contenido participativo que los jóvenes interactivos transmiten en el uso de TIC y de las redes sociales durante el origen del movimiento social del 15M. Los objetivos se han dirigido a comprobar cómo los jóvenes sienten, viven y experimentan la ciudadanía democrática a través de los soportes digitales y mediáticos, participando en el lugar público de la plaza donde se está formando una más informada ciudadanía digital entre la convergencia tecnológica, la hipertextualidad y la no linealidad. Se ha tratado de identificar tanto el contenido educativo de sus interacciones e implicaciones como el uso de los soportes digitales mediáticos en su organización colectiva. La metodología utilizada es el estudio de caso en profundidad, realizado durante los días de la acampada en la plaza pública, recogiendo observaciones, entrevistas, información de las redes sociales (Twitter, Facebook, n-1 y Tuenti), noticias de los medios de comunicación así como de los medios generados en la acampada, y todas las fotografías y cartelería del evento. Desde esta perspectiva tecnoeducativa se analiza cómo estos jóvenes ensanchan sus relaciones comunicativas y se conectan en red construyendo nuevos significados de lo educativo, lo social y lo político. El análisis de sus discursos nos descubre una reapropiación de los jóvenes de las TIC participando en la comunicación pública y aportando nuevas perspectivas para la educación ciudadana.
Expanding Community: Youth, Social Networking and Schools
Authors: Stornaiuolo Amy , DiZio Jennifer , Hellmich Emily 
Published: January 2013

This study examined the construct of community and its development in online spaces through a qualitative analysis of middle school students’ participation in a private social network. Drawing on notions of community inspired by philosopher Jean-Luc Nancy, we found that students, despite not knowing one another previously, were willing both to encounter and come to know each other, using the resources of the network to build the trust that became foundational to their online social relationships. They did so primarily through two kinds of interactional effort that we call «public work» and «proximity work». Negotiating their positions relative to one another (proximity work) and across public/private spaces (public work), youth used a variety of semiotic tools to establish relationships and address the considerable challenges of digitally mediated communication with unknown others. This study suggests that educationally focused social networks can be designed for, or their uses primed toward, communicative purposes and activities foregrounding reciprocal exchange that is ethically alert and socially aware, and that schools and other educational institutions, though historically resistant to technological innovation, have an important role to play in this process.Inspiradas por las nociones de comunidad del filósofo Jean-Luc Nancy, nuestro estudio examina el concepto de comunidad y su desarrollo en entornos virtuales a través de un análisis cualitativo de la participación de alumnos de educación secundaria obligatoria (de 11 a 14 años de edad) en una red social privada. Nuestros datos indican que los alumnos, a pesar de no conocerse previamente, estaban dispuestos a conocerse y relacionarse, y a utilizar recursos de una red social privada para desarrollar la confianza necesaria para mantener sus amistades virtuales. Para lograrlo, los estudiantes usaron dos métodos de interrelación que llamamos «trabajo público» y «trabajo de proximidad». Al negociar sus posiciones relativas a los otros estudiantes (trabajo de proximidad) y a través de espacios públicos y privados (trabajo público), los jóvenes utilizaron diversos instrumentos semióticos para entablar amistad y para enfrentarse a los numerosos retos de la comunicación con desconocidos a través de medios digitales. Este estudio indica que las redes sociales educativas pueden ser diseñadas con fines comunicativos y para actividades que ponen de relieve los intercambios recíprocos que son éticamente y socialmente conscientes. Por último, los resultados sugieren que, aunque históricamente han demostrado una resistencia a la innovación tecnológica, las escuelas y otras instituciones educativas tienen un papel importante que desempeñar en este proceso.