723 research outputs found

    Analysis of the Cytisetea scopario-striati scrubs in the south-west-centre of the Iberian Peninsula

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    The statistical and phytosociological study of 255 relevés taken in the south-west of the Iberian Peninsula and made up of our own samples and previous publications reveals how close these relevés, previously ascribed to different syntaxa, really are. Our re-arrangement of the data leads us to propose for the territory the 15 associations already published and three new ones, namely: Genisto floridae-Adenocarpetum argyrophylli ass. nova hoc loco, Cytisetum bourgaei- eriocarpi nova, Lavandulo viridis-Cytisetum striati ass. nova hoc. loco. We also suggest a name correction, Adenocarpo anisochili-Cytisetum scoparii J.C. Costa et al. 2000 corr., and a status change, namely, Ulici latebracteati- Cytisetum striati (Costa et al. 2000) status novo

    Distribution patterns of endemic flora to define hotspots on Hispaniola

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    Nineteen areas on the island of Hispaniola (Haiti and the Dominican Republic) were studied with the aim of determining the distribution pattern of the endemic flora in these areas, and their variability with altitude. The main concentration of endemic species occurs in mountains with a medium altitude and in certain mountain sites (palaeo-islands), which coincide with hotspots; a lower number of endemics are found in low-lying areas (coldspots), due to the degradation of their habitats. A total of 1,582 endemic species were studied and were distributed in 19 areas. The whole island is of outstanding interest for its richness in endemics; it has 2,050 endemic species, representing 34.16% of its total flora. The territory in the study is home to 1,284 genera of which 31 are endemic to the island, including monotypical genera such as Tortuella abietifolia Urb. & Ekman, and endemic genera such as Hottea, containing seven endemic species. The sites with the highest rate of endemics are area A16 in the central range with a total of 440 endemic species, of which 278 are exclusive to the territory; and the Sierra de Bahoruco, la Selle, La Hotte and Tibur on in area A12, where we found 699 plants of which 482 are endemic and exclusive to the area; and A13 with 173 and 129 respectively. This work highlights the exceptional floristic diversity in endemic species and genera and analyses their distribution patterns as a tool for conservation in this area of the world, whose high endemicity rate makes it one of the most significant hotspots in the Caribbean

    Expansion of the Juniperus Genus due to Anthropic Activity

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    This work contains a study of Juniperus forests in the southern Iberian Peninsula and aims to determine their floristic composition and their biogeographical, ecological and bioclimatological distribution. The analysis of Juniperus formations revealed a series of different plant communities. The presence of endemic companions in these plant communities justifies the study of these islands: Echinospartum ibericum Rivas Mart., Sánchez Mata & Sancho, Adenocarpus argyrophyllus (Rivas Goday) Caball., Digitalis purpurea L. subsp. mariana (Boiss.) Rivas Goday, Sideritis lacaitae Font Quer, Coincya longirostra (Boiss) Greuter & Burdet, Cytisus scoparius (L.) Link subsp. bourgaei (Boiss.) Riv.-Mart., Cytisus striatus (Hill) Rothm. subsp. eriocarpus (autor), Genista polyanthos R. Roem. Ex Willk., Dianthus crassipes R. de Roemer, Dianthus lusitanus Brot. Digitalis thapsi L., Digitalis purpurea L. subsp. Heywoodii P. Silva & M. Silva, subsp. mariana (Boiss) Rivas Goday, Securinega tinctoria (L.) Rothm., Lavandula stoechas L. subsp. luisieri (Rozeira) Rozeira, lavandula stoechas subsp. sampaiana Rozeira, Genista hirsuta Vahl, Thymus mastichina (L.) L., Thymus grantensis Boiss. subps. micranthus (Willk.) O. Boòs & Vigo, Thymus zygis Loefl ex L. subsp. gracillis (Boiss.) Boiss., Antirrhinum graniticum Roth. subsp. onubensis (Fernández Casas) Valdés. The territories in the study are of community interest (SCI) due to the presence of habitats such as Habitat 8220, which includes the plant associations Digitali thapsi-Dianthetum lusitani Rivas-Martínez ex Fuente 1986, Jasiono marianae-Dianthetum lusitani Rivas Goday (1955) 1964, Coincyo longirostraae-Dianthetum lusitani Melendo in Cano, Melendo & F. Valle 1997, and is the motive for the need to conserve these areas. However the dominant species in these environments is Juniperus oxycedrus L. subsp. lagunae (Pau ex C. Vicioso) Rivas Mart., and all the other –mainly endemic– species are located within its vicinity. These zones can thus be classified as hotspots with particular interest for conservation. Areas dominated by Juniperus are currently becoming more widespread due to the greater prevalence of rock beds, which increase every year in response to deforestation and forest fires. This phenomenon leads to the extension of edaphoxerophilous zones and a decrease in climatophilous zones, and creates more potential areas that can potentially act as a refuge for endemic species

    New Method for Increasing Sustainable Agricultural Yield

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    The main objective of this study is to look for a new method, to obtain the maximum production, and the minimum economic and environmental cost. Scientific advances in bioclimatology have brought a greater understanding of the functioning of plant individuals, populations and communities, and the study and interpretation of bioclimatic indices reveals the close relationship between the values of these indices and crop yields. In cases where insufficient meteorological data are available to allow the various formulas to be applied, thermoclimatic and ombroclimatic bioindicators must be used, some of which have been collected by us in previous works. This paper contains a bioclimatic study of the southern Iberian Peninsula in relation to the main olive varieties grown in these territories. We establish the values of some key indices for cultivation: continentality index (Ic), which determines the annual thermal range and allows us to establish the period of vegetative activity (PAV); the ombrothermic index (Io), which measures the ombrotype in the different sites; and the thermicity and compensated thermicity index, which denote the thermotype in the territory (It/Itc). In the relationship between the value of the bioclimatic indices and olive production, good fits are obtained in the regression analysis with R2> 0.90, and is very positive influence of the different parameters used. In conclusion the greatest influence on the production of Ic is between 18.5-19.5, Io 3.5-4.5 and It / Itc 320-350. This allows to obtain areas of maximum production with a lower economic cost

    Multimodal analysis of advertising discourse during the lockdown due to COVID-19: Comparison of the communication strategies of financial services and automotive products in Spain

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    The goal of the following text is to analyze the changes in television advertising in the banking and automobile sectors, according to the social context. The hypothesis is that communication is significantly influenced by the situational context, causing differences between the advertising of the two sectors. A multimodal discourse analysis is used, comparing twenty commercials from the banking and automobile sectors in 2019 and 2020, the period during which the lockdown due to COVID-19 took place. Based on a qualitative and quantitative analysis tables were developed with which to analyze general data such as the value proposition or target audience of the advert, or other special data like the text (verb tenses, rhetorical figures…), the image and the sound used. The fact that context is decisive in communication is made evident, and since this is different in every sector, the communication strategy is clearly different as well. However, the points that the two sectors have in common are remarkable: these range from talking about brands and products, to speaking for and about people

    Foreword by guest editors for the Special Issue on the 2013 ICUFN Conferencs

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    Jeong, S.; Rodrigues, JJPC.; Cano Escribá, JC. (2014). Foreword by guest editors for the Special Issue on the 2013 ICUFN Conferencs. Wireless Personal Communications. 78(4):1827-1831. doi:10.1007/s11277-014-2046-yS1827183178

    Highlights: IEEE ITS Society Technical Committee on Mobile Communications Networks for ITS

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    [EN] The TC on 'Mobile Networks for ITS' has been in existence since 2005. It will continue to initiate activities (through journal and magazine special issues, workshops, conferences, forums, etc.,) and to promote the technical interactions among professionals in the field. The success of the TC will depend on the contributions of its members and organizers. We would like to thank Prof. Urbano Nunes (VP Technical Activities) for inviting us to submit this highlight. We would also like to thank all the TC members who have supported us over the years. We look forward to your continual participation in the future.This work was partially supported by the Ministerio de Ciencia e Innovación, Spain, under Grant TIN2011-27543-C03-01.Toh, CK.; Higashino, T.; Cano Escribá, JC.; Weigle, MC. (2012). Highlights: IEEE ITS Society Technical Committee on Mobile Communications Networks for ITS. IEEE Intelligent Transportation Systems Magazine. 4(1):33-37. doi:10.1109/MITS.2011.2178875S33374

    Adaptación de los métodos de enseñanza a los métodos de aprendizaje de los alumnos

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    El actual proceso de adaptación al Espacio Europeo de Educación Superior (EEES) que estamos viviendo en la Universidad, y que tiene como objetivo favorecer la convergencia europea en materia de educación universitaria, ha destacado algunos aspectos que pueden ser cambiados por parte de los docentes en aras de mejorar el proceso de enseñanza/ aprendizaje. En el presente artículo, presentamos unas directrices que pueden ayudar a los docentes a adaptar los métodos de enseñanza, para que se adecúen al máximo a las capacidades de aprendizaje de los alumnos que cursan sus asignaturas.Peer Reviewe

    Indicative value of the dominant plant species for a rapid evaluation of the nutritional value of soils

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    A study was conducted on 14 grassland communities located in the south of the Iberian Peninsula and their edaphology, which is identified as specific plant associations. The edaphic study of each association allows a rapid evaluation of the nutrient content in the soil without the need for laboratory edaphic analysis. For each phytosociological relevé and soil, samplings were carried out. The field data were subjected to various statistical analysis—canonical correspondence analysis (CCA), Bayesian networks, and decision trees—to establish nutrient content. When the abundance value of the species is 9 in the Van der Maarel scale, there is an increase in the values of several soil parameters. In the case of Hordeum leporinum, when the Van der Maarel index is 9, the Kc (exchangeable potassium in cmol/kg) undergoes the greatest variation, to a value of up to 0.729 cmol/kg. The application of the decision tree to this species reveals that the soil attributes with the greatest influence in the classification are conductivity, %_si (silt texture), pH, and pF 15 atm (pressure at 15 atmospheres (water retention capacity) in %). Indeed, this interlaced edaphic and phytosociological study provides us with a high-value tool to obtain quick information on the content of nutrients in the soil.info:eu-repo/semantics/publishedVersio

    Determining the representative factors affecting warning message dissemination in VANETs

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    In this paper, we present a statistical analysis based on the 2k factorial methodology to determine the representative factors affecting traffic safety applications in Vehicular ad hoc networks (VANETs). Our purpose is to determine what are the key factors affecting Warning Message Dissemination (WMD) in order to concentrate on such parameters, thus reducing the amount of required simulation time when evaluating VANETs. Simulation results show that the key factors affecting warning messages delivery are: (i) the transmission range, (ii) the radio propagation model used, and (iii) the density of vehicles. Based on this statistical analysis, we evaluate a compound key factor: neighbor density. This factor combines the above-mentioned factors into a single entity, reducing the number of factors that must be taken into account for VANET researchers to evaluate the benefits of their proposals.This work was partially supported by the Ministerio de Educacion y Ciencia, Spain, under Grant TIN2008-06441-C02-01, and by the Fundacion Antonio Gargallo, under Grant 2009/B001.Martínez Domínguez, FJ.; Toh, CK.; Cano Escribá, JC.; Tavares De Araujo Cesariny Calafate, CM.; Manzoni, P. (2012). Determining the representative factors affecting warning message dissemination in VANETs. Wireless Personal Communications. 67(2):295-314. https://doi.org/10.1007/s11277-010-9989-4S295314672Eichler, S. (2007). Performance evaluation of the IEEE 802.11p WAVE communication standard. In Proceedings of the vehicular technology conference (VTC-2007 Fall), USA.Fall, K., & Varadhan, K. (2000). ns notes and documents. The VINT Project. UC Berkeley, LBL, USC/ISI, and Xerox PARC. Available at http://www.isi.edu/nsnam/ns/ns-documentation.html .Fasolo, E., Zanella, A., & Zorzi, M. (2006). An effective broadcast scheme for alert message propagation in vehicular ad hoc networks. In Proceedings of the IEEE International Conference on Communications, Istambul, Turkey.Korkmaz, G., Ekici, E., Ozguner, F., & Ozguner, U. (2004). Urban multi-hop broadcast protocols for inter-vehicle communication systems. In Proceedings of First ACM Workshop on Vehicular Ad Hoc Networks (VANET 2004).Martinez, F. J., Toh, C.-K., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2009). Realistic radio propagation models (RPMs) for VANET simulations. In IEEE wireless communications and networking conference (WCNC), Budapest, Hungary.Martinez, F. J., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2008). CityMob: A mobility model pattern generator for VANETs. In IEEE vehicular networks and applications workshop (Vehi-Mobi, held with ICC), Beijing, China.Martinez, F. J., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2009). A performance evaluation of warning message dissemination in 802.11p based VANETs. In IEEE local computer networks conference (LCN 2009), Zürich, Switzerland.Torrent-Moreno, M., Santi, P., & Hartenstein, H. (2005). Fair sharing of bandwidth in VANETs. In Proceedings of the 2nd ACM international workshop on vehicular ad hoc networks, Germany.Tseng Y.-C., Ni S.-Y., Chen Y.-S., Sheu J.-P. (2002) The broadcast storm problem in a mobile ad hoc network. Wireless Networks 8: 153–167Wisitpongphan N., Tonguz O., Parikh J., Mudalige P., Bai F., Sadekar V. (2007) Broadcast storm mitigation techniques in vehicular ad hoc networks. Wireless Communications IEEE 14(6): 84–94. doi: 10.1109/MWC.2007.4407231Yang, X., Liu, J., Zhao, F., & Vaidya, N. H. (2004). A vehicle-to-vehicle communication protocol for cooperative collision warning. In Proceedings of the first annual international conference on mobile and ubiquitous systems: Networking and services (MobiQuitous’04).Yoon, J., Liu, M., & Noble, B. (2003). Random waypoint considered harmful. Proceedings of IEEE INFOCOMM 2003, San Francisco, California, USA.Zang, Y., Stibor, L., Cheng, X., Reumerman, H.-J., Paruzel, A., & Barroso, A. (2007). Congestion control in wireless networks for vehicular safety applications. In Proceedings of the 8th European Wireless Conference, Paris, France
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