109 research outputs found

    Small structure, big significance: seed morphology of South American species of M itracarpus (Rubiaceae - Spermacoceae)

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    Mitracarpus Zuce, ex Schult. & Schult.f. comprises about 50 species distributed mainly throughout tropical and subtropical regions of the New World, from Southern United States to central Argentina. Considering the importance of micromorphological characters for the taxonomy of Spermacoceae s.s. (Rubiaceae), the present study aimed to analyse the taxonomic significance of seed micromorphology in Mitracarpus species from South America. The seeds of 29 species were analysed through light microscopy and scanning electrón microscopy (SEM). For SEM analyses the seeds were mounted on stubs, air dried, covered with gold-palladium. The analyses revealed four pattems and eight subtypes in Mitracarpus, based mainly on the shape of the ventral groove and exotesta features: (1) X-shaped groove: 1.1. reticulate-areolate exotesta, without cruciform depression (M eritricoides, M. parvulus, M. longicalyx, M. nitidus)', 1.2. reticulate-areolate exotesta, with cruciform depression (M. albomarginatus, M. bacigalupoae, M. femandesii); 1.3. reticulate-foveate exotesta, without cruciform depression (M. brasiliensis, M. federalensis, M. hirtus, M. microspermus, M. nitidus, M. polygonifolius); 1.4. papillate exotesta, without cruciform depression (M. pusillus, M. recurvatus, M. steyermarkii); 1.5. reticulate-foveate exotesta, with cruciform depression (M. anthospermoides,M. carajasensis,M. baturitensis,M. bicrucis,M. frigidus); (2) Inverted-Y-shaped groove, reticulate-foveate exotesta, without cruciform depression (M. eichleri, M. salzmannianus, M. semirianus); (3) Rectangularquadrangular-shaped groove, reticulate-areolate exotesta, without cruciform depression (M hasslerianus, M. Ihotzkyanus, M. megapotamicus, M. rigidifolius); (4) Oblong-shaped groove, reticulate-foveate exotesta, without cruciform depression (M. diversifolius). The data obtained here have shown the systematic importance o f seed characteristics in Mitracarpus, as well their valué to indicate affinities among species. It is expected that this study regarding the seed characters in Mitracarpus can provide a potential source o f apomorphies to discem the clades in future molecular phylogenetic analyses. Acknowledgements: FUNCAP (Process BP5-0197-00136.01.00/22); Royal Botanic Gardens, Kew; KLARF (Kew Latín American Research Fellowships Programme); CONICET

    Recognition of Crowd Behavior from Mobile Sensors with Pattern Analysis and Graph Clustering Methods

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    Mobile on-body sensing has distinct advantages for the analysis and understanding of crowd dynamics: sensing is not geographically restricted to a specific instrumented area, mobile phones offer on-body sensing and they are already deployed on a large scale, and the rich sets of sensors they contain allows one to characterize the behavior of users through pattern recognition techniques. In this paper we present a methodological framework for the machine recognition of crowd behavior from on-body sensors, such as those in mobile phones. The recognition of crowd behaviors opens the way to the acquisition of large-scale datasets for the analysis and understanding of crowd dynamics. It has also practical safety applications by providing improved crowd situational awareness in cases of emergency. The framework comprises: behavioral recognition with the user's mobile device, pairwise analyses of the activity relatedness of two users, and graph clustering in order to uncover globally, which users participate in a given crowd behavior. We illustrate this framework for the identification of groups of persons walking, using empirically collected data. We discuss the challenges and research avenues for theoretical and applied mathematics arising from the mobile sensing of crowd behaviors

    The health determinants in young children: Testing a new surveillance system in Italy

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    In recent years, the scientific community has stressed the need to invest in the first 1,000 days of life - the time spanning between conception and the 2nd birthday - because it is during this period that the foundations of health are laid and whose effects will be present throughout the life and may influence the next generation. Taking this into account, in 2013 the National Centre for Disease Prevention and Control (CCM) of the Italian Ministry of Health promoted and financed a project to test a surveillance system of the main determinants of health concerning the child between the conception period and the 2nd years of life which are included in the National Programme “GenitoriPiù”: folic acid before and during pregnancy, abstention from tobacco and alcohol during pregnancy and lactation, breastfeeding, infant sleep position, vaccination attitude, and early reading. The Project, started in January 2014 and ended in August 2016, has piloted the design, testing, and evaluation of the surveillance system with the view to national extension and the repeatability over time. The surveillance system has been designed to collect data through a questionnaire compiled by mothers in vaccination centres, in order to produce indicators which will enable territorial and intertempo-ral comparisons to be made. The project has shown the feasibility of this system, identifying favourable conditions and possible difficulties, and its ability to collect important information on children's health

    Tissue culture of ornamental cacti

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    Espécies crípticas em Pagamea coriacea sensu lato (Rubiaceae): evidências morfológicas, ecológicas e de comportamento reprodutivo em um contexto simpátrico

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    In this study we explore morphological and ecological variation in sympatric populations of Pagamea coriacea s.l. - a species complex from white-sand vegetation in the Amazon. A total of 147 trees were sampled and monitored at three nearby sites in Central Amazon, Brazil. Multivariate analyses of morphology indicated two distinct groups (A and B), which also differed in bark type, each containing subgroups associated with sexual dimorphism. However, a single hermaphroditic individual was observed within group B. As expected, all pistillate plants produced fruits, but 23% of the staminate plants of group B, and 5% of group A also produced fruits. This variation suggests that the sexual systems of both groups are between dioecy and gynodioecy. There was an overlap in flowering phases between the two groups, but the pattern of floral maturation differed. Ecologically, plants of group B were found in more shaded habitats and over sandstone bedrocks, while group A was prevalent in deeper sandy soils as canopy plants. The significances of morphological and environmental differences were tested by a multivariate analysis of variance, and a canonical discriminant analysis assessed the importance of variables. The coexistence in sympatry of two discrete morphological groups in the P. coriacea s.l., with different habitat preferences and reproductive behaviors, indicates they represent distinct species.O objetivo deste estudo foi testar se o complexo de espécies Pagamea coriacea inclui múltiplas espécies, usando evidências morfológicas, ecológicas e de comportamento reprodutivo. Um total de 147 árvores foram amostradas e monitoradas em três locais próximos na Amazônia Central, Brasil. Análises multivariadas de dados morfológicos indicaram dois grupos discretos (A e B), que coincidem com diferenças no tipo de casca, cada um por sua vez com subgrupos que representam dimorfismo sexual. Contudo, um indivíduo distintamente hermafrodita foi encontrado no grupo B. Todas as plantas pistiladas produziram frutos, mas também foram observados frutos para 23% das plantas estaminadas do grupo B, e para 5% das estaminadas do grupo A. Essa variação sugere que ambos grupos possuem um sistema sexual entre dioicia e ginodioicia. Houve sobreposição das fases de floração e frutificação entre os dois grupos, mas o padrão de maturação de flores foi diferente. Quanto ao hábitat, o grupo B predominou em situações de sombra e em solos arenosos rasos sobre lajes de pedra, enquanto o grupo A ocorreu em solos arenosos mais profundos e no dossel da vegetação. A coexistência de dois grupos morfológicos discretos no complexo P. coriacea s.l., com diferenças ecológicas e de comportamento reprodutivo, indica que correspondem a duas espécies distintas
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