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Sample records for fern mohria caffrorum

  1. Systematic studies in the genus Mohria (Anemiaceae: Pteridophyta. III. Comparative sporangium and spore morphology

    Directory of Open Access Journals (Sweden)

    J. P. Roux

    1992-10-01

    Full Text Available The genera Mohria and Anemia (Anemiaceae: Pteridophyta can be separated on both their sporangia and spores. In Mohria the capsule is globose with an apical annulus but in Anemia it is ovate-globose to cylindrical with a subapical annulus. The spores of both genera are radially symmetrical, tetrahedral and trilete with near parallel muri. The exinal sculpture in Mohria is cicatricose and in Anemia it can be canaliculate or cicatricose. In both genera the mural sets anastomose to form common muri that extend from near the distal pole to the equatorial radial region. The muri in Mohria are hollow and differ from those in Anemia which are solid or microporate. Supramural sculpturing in Mohria and Anemia is perinous. Spores of the other schizaealean ferns show no or little taxonomic affinities with Mohria and Anemia. In Actinostachys and Schizaea the spores are monolete and in  Lygodium trilete but the exinal sculpture is smooth.

  2. New taxa, combinations and records of Pteridophyta from southern and central Africa

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    J. E. Burrows

    1989-12-01

    Full Text Available Four new taxa of ferns are described and illustrated from southern Africa:  Ophioglossum convexum J.E. Burrows, Mohria caffrorum (L. Desv. var. ferruginea J.E. & S.M. Burrows,  Marsilea farinosa Launert subsp. arrecta J.E. Burrows and Asplenium sebungweense J.E. Burrows. The combination of Grammitis rigescens (Bory ex Willd. J.E. Burrows is made. Ophioglossum thomasii Clausen,  O. rube Hum Welw. ex A. Braun.  Vinana ensiformis Swartz and Asplenium buettneri Hieron. ex Brause are new records for Zimbabwe, while Hymenophyllum splendidum V.d. Bosch and  Asplenium uhligii Hieron. are new records for Malawi and Zimbabwe. Actiniopteris semiflabellata Pichi-Sermolli is recorded from Namibia and Thelypteris oppositiformis (C. Chr. Ching is recorded from the Transvaal.

  3. Bracken fern poisoning

    Science.gov (United States)

    Bracken fern (Pteridium aquilinum) has worldwide distribution and in some areas dominated plant communities replacing desirable forages. Poisoning is identified as enzootic hematuria, bright blindness, and bracken staggers. This chapter reviews updates new information on the plant, the various poi...

  4. Ferns and fern allies of District Shopian, Kashmir Valley, India

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    SHAKOOR A. MIR

    2015-04-01

    Full Text Available Abstract. Mir SA, Mishra AK, Pala SA, Reshi ZA, Sharma MP. Ferns and fern allies of District Shopian, Kashmir Valley, India Biodiversitas 16: 27-43. Shopian, recently created hilly district of Kashmir valley, Jammu and Kashmir is surrounded by the lofty mountains of Pir-Panjal range. More than half area of district is occupied by different forests, subalpine, alpine and mountainous zones. Great altitudinal variation, adequate rainfall, high forest cover, large number of streams, springs and topographic variations render the district worthy for supporting rich fern flora. Therefore, the current study was aimed to undertake in-depth systematic survey of different habitats of Shopian for the collection of diversity of pteridophytes. Specimens were collected during 2010, 2011 and 2012 growing seasons from June to November. A total 81 species of ferns and fern allies belonging 27 genera and 11 families were reported. The dominant families of the region are Dryopteridaceae (25 species followed by Woodsiaceae (16 species, Aspleniaceae (13 species and Pteridaceae (12 species. Similarly, the dominant genera collected from here are Dryopteris (14 species, Asplenium (13, Polystichum (11 species and Athyrium (6 species. A list of the fern and fern allies, along with update nomenclature, their selected Synonym, diagnostic features, distributional and ecological notes have been provided here.

  5. New species of Malaysian ferns

    NARCIS (Netherlands)

    Holttum, R.E.

    1962-01-01

    The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

  6. Screening for ptaquiloside in ferns

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Pedersen, Henrik Ærenlund

    2017-01-01

    . Objective: To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. Methodology: PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after....... A selection of up to 50 years old Bracken herbarium specimens were tested for PTA and PtB. The methodology was applied on 21 fern species from Denmark. Results: An optimised TFA-based method results in 30.7% higher conversion and a 1:1 reaction between PTA and PtB. Full three-dimensional resolution......: Herbarium specimens up to 50 years old can be used for explorative risk assessment of ferns using HPLC-DAD for quantification and identification....

  7. Ecological anatomy of ferns fronds

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    Nina M. Derzhavina

    2014-04-01

    Full Text Available Structural types of frond anatomy are distinguished on the basis of investigation of 30 species of homosporous ferns and with regard for literature: hydromorphic, hygromorphic, mesomorphic, subxeromorphic, and subsucculent (cryptic succulent. Following frond traits are of highest adaptive value: their area and thickness, type of mesophyll, dry weight of an area unit – specific superficial density, cellular volume, and number of cells per unit of frond area.

  8. An Exploration into Fern Genome Space.

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    Wolf, Paul G; Sessa, Emily B; Marchant, Daniel Blaine; Li, Fay-Wei; Rothfels, Carl J; Sigel, Erin M; Gitzendanner, Matthew A; Visger, Clayton J; Banks, Jo Ann; Soltis, Douglas E; Soltis, Pamela S; Pryer, Kathleen M; Der, Joshua P

    2015-08-26

    Ferns are one of the few remaining major clades of land plants for which a complete genome sequence is lacking. Knowledge of genome space in ferns will enable broad-scale comparative analyses of land plant genes and genomes, provide insights into genome evolution across green plants, and shed light on genetic and genomic features that characterize ferns, such as their high chromosome numbers and large genome sizes. As part of an initial exploration into fern genome space, we used a whole genome shotgun sequencing approach to obtain low-density coverage (∼0.4X to 2X) for six fern species from the Polypodiales (Ceratopteris, Pteridium, Polypodium, Cystopteris), Cyatheales (Plagiogyria), and Gleicheniales (Dipteris). We explore these data to characterize the proportion of the nuclear genome represented by repetitive sequences (including DNA transposons, retrotransposons, ribosomal DNA, and simple repeats) and protein-coding genes, and to extract chloroplast and mitochondrial genome sequences. Such initial sweeps of fern genomes can provide information useful for selecting a promising candidate fern species for whole genome sequencing. We also describe variation of genomic traits across our sample and highlight some differences and similarities in repeat structure between ferns and seed plants. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  9. rFerns: An Implementation of the Random Ferns Method for General-Purpose Machine Learning

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    Miron B. Kursa

    2014-11-01

    Full Text Available Random ferns is a very simple yet powerful classification method originally introduced for specific computer vision tasks. In this paper, I show that this algorithm may be considered as a constrained decision tree ensemble and use this interpretation to introduce a series of modifications which enable the use of random ferns in general machine learning problems. Moreover, I extend the method with an internal error approximation and an attribute importance measure based on corresponding features of the random forest algorithm. I also present the R package rFerns containing an efficient implementation of this modified version of random ferns.

  10. Structure and ontogeny of stomata in ferns

    NARCIS (Netherlands)

    Sen, U.; De, B.

    1992-01-01

    On the basis of ontogeny and arrangement of the surrounding cells the stomata in ferns are classified into twenty-four types of which seven – plupolocytic, pseudocopolocytic, sepcopolocytic, pseudohemiparacytic, pluhemiparacytic, pluparacytic and codiacytic – are new. The ontogenetic

  11. Boosted Random Ferns for Object Detection.

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    Vergel, Michael Villamizar; Andrade-Cetto, Juan; Sanfeliu, Alberto; Moreno-Noguer, Francesc

    2018-02-01

    In this paper we introduce the Boosted Random Ferns (BRFs) to rapidly build discriminative classifiers for learning and detecting object categories. At the core of our approach we use standard random ferns, but we introduce four main innovations that let us bring ferns from an instance to a category level, and still retain efficiency. First, we define binary features on the histogram of oriented gradients-domain (as opposed to intensity-), allowing for a better representation of intra-class variability. Second, both the positions where ferns are evaluated within the sliding window, and the location of the binary features for each fern are not chosen completely at random, but instead we use a boosting strategy to pick the most discriminative combination of them. This is further enhanced by our third contribution, that is to adapt the boosting strategy to enable sharing of binary features among different ferns, yielding high recognition rates at a low computational cost. And finally, we show that training can be performed online, for sequentially arriving images. Overall, the resulting classifier can be very efficiently trained, densely evaluated for all image locations in about 0.1 seconds, and provides detection rates similar to competing approaches that require expensive and significantly slower processing times. We demonstrate the effectiveness of our approach by thorough experimentation in publicly available datasets in which we compare against state-of-the-art, and for tasks of both 2D detection and 3D multi-view estimation.

  12. Trends and concepts in fern classification

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    Christenhusz, Maarten J. M.; Chase, Mark W.

    2014-01-01

    Background and Aims Throughout the history of fern classification, familial and generic concepts have been highly labile. Many classifications and evolutionary schemes have been proposed during the last two centuries, reflecting different interpretations of the available evidence. Knowledge of fern structure and life histories has increased through time, providing more evidence on which to base ideas of possible relationships, and classification has changed accordingly. This paper reviews previous classifications of ferns and presents ideas on how to achieve a more stable consensus. Scope An historical overview is provided from the first to the most recent fern classifications, from which conclusions are drawn on past changes and future trends. The problematic concept of family in ferns is discussed, with a particular focus on how this has changed over time. The history of molecular studies and the most recent findings are also presented. Key Results Fern classification generally shows a trend from highly artificial, based on an interpretation of a few extrinsic characters, via natural classifications derived from a multitude of intrinsic characters, towards more evolutionary circumscriptions of groups that do not in general align well with the distribution of these previously used characters. It also shows a progression from a few broad family concepts to systems that recognized many more narrowly and highly controversially circumscribed families; currently, the number of families recognized is stabilizing somewhere between these extremes. Placement of many genera was uncertain until the arrival of molecular phylogenetics, which has rapidly been improving our understanding of fern relationships. As a collective category, the so-called ‘fern allies’ (e.g. Lycopodiales, Psilotaceae, Equisetaceae) were unsurprisingly found to be polyphyletic, and the term should be abandoned. Lycopodiaceae, Selaginellaceae and Isoëtaceae form a clade (the lycopods) that is

  13. How Fern Creek Is Beating Goliath

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    Donovan, Margaret; Galatowitsch, Patrick; Hefferin, Keri; Highland, Shanita

    2013-01-01

    The "David" is Fern Creek Elementary, a small urban school in Orlando, Florida, that serves an overwhelmingly disadvantaged student population. The "Goliaths" are the mountains of problems that many inner-city students face--poverty, homelessness, mobility, instability, limited parent involvement, and violent neighborhood…

  14. Characterisation of polysaccharides from the fern Platycerium ...

    African Journals Online (AJOL)

    Platycerium bifurcatum, a widely growing fern was collected and the phytochemical analysis of the powdered plant showed that polysaccharides were present in appreciable quantity. It was found that 4.0 % sodium hydroxide solution was required for optimum extraction and then precipitated using 99.0 % ethanol in an ...

  15. Photosynthesis limitations in three fern species.

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    Gago, Jorge; Coopman, Rafael E; Cabrera, Hernán Marino; Hermida, Carmen; Molins, Arántzazu; Conesa, Miquel À; Galmés, Jeroni; Ribas-Carbó, Miquel; Flexas, Jaume

    2013-12-01

    Maximum photosynthesis rates in ferns are generally lower than those of seed plants, but little is known about the limiting factors, which are crucial to understand the evolution of photosynthesis in land plants. To address this issue, a gas exchange/chlorophyll fluorescence analysis was performed in three fern species spanning high phylogenetic range within Polypodiopsida (Osmunda regalis, Blechnum gibbum and Nephrolepis exaltata) to determine their maximum net photosynthesis (AN ), stomatal (gs ) and mesophyll (gm ) conductances to CO2 , and the maximum velocity of carboxylation (Vc,max ). The in vitro Rubisco specificity factor (SC /O ) was also determined. All three species had values for SC /O similar to those typical of seed plants, but values of AN , gs , gm and Vc,max were within the lowest range of those observed in seed plants. In addition, gs was unresponsive to light and CO2 , as already described in other fern species. On the contrary, gm varied with changes CO2 . A quantitative photosynthesis limitation analysis suggested that early land plants (ferns) presented not only stomatal limitations-which were less adjustable to the environment-but also restricted gm and Vc,max , resulting in limited maximum photosynthesis rates. © 2013 Scandinavian Plant Physiology Society.

  16. Food uses of ferns in China: a review

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    Yujing Liu

    2012-11-01

    Full Text Available Edible ferns are some of the most important wild vegetables in China. This paper reviews their food uses. The history of eating ferns in China may go back as far as 3000 years. An ethnobotanical inventory of edible ferns was created, with 52 species (including 4 varieties, which were traditionally used. The potential species number of edible ferns was estimated as 144 species (including 4 varieties. The cuisines, products and chemical components of ferns were also summarized. The most commonly eaten fern, Pteridium aquilinum var. latiusculum, was discussed in terms of its toxicity, massive productivity and development strategies. Suggestions and recommendations were proposed for the future development of edible ferns in China.

  17. The fern sporangium: a unique catapult.

    OpenAIRE

    Noblin, X.; Rojas, N. O.; Westbrook, J.; Llorens, C.; Argentina, M.; Dumais, J.

    2012-01-01

    International audience; Various plants and fungi have evolved ingenious devices to disperse their spores. One such mechanism is the cavitation-triggered catapult of fern sporangia. The spherical sporangia enclosing the spores are equipped with a row of 12 to 13 specialized cells, the annulus. When dehydrating, these cells induce a dramatic change of curvature in the sporangium, which is released abruptly after the cavitation of the annulus cells. The entire ejection process is reminiscent of ...

  18. Structure and ontogeny of stomata in ferns

    OpenAIRE

    Sen, U.; De, B.

    1992-01-01

    On the basis of ontogeny and arrangement of the surrounding cells the stomata in ferns are classified into twenty-four types of which seven – plupolocytic, pseudocopolocytic, sepcopolocytic, pseudohemiparacytic, pluhemiparacytic, pluparacytic and codiacytic – are new. The ontogenetic interrelationships among different stomatal types are traced and the role of stomata in determining the taxonomic position of Psilotum, Tmesipteris and the Ophioglossum group of genera are discussed. It is conclu...

  19. Thirteen new records of ferns from Brazil.

    Science.gov (United States)

    Almeida, Thais Elias; Salino, Alexandre

    2015-01-01

    Thirteen fern species are reported for the first time for Brazil. Among the new records, eight are from Acre state (Cyatheasubincisa, Cyclodiumtrianae, Elaphoglossumstenophyllum, Hypoderrisbrauniana, Pleopeltisstolzei, Thelypterisarcana, Thelypteriscomosa, Thelypterisvaldepilosa), two are from Pará state (Polypodiumflagellare, Tectariaheracleifolia), one from Minas Gerais state (Alsophilasalvinii), one from Ceará state (Campyloneurumcostatum) and one from Bahia state (Thelypterisrolandii). Part of the species shows a disjunct occurrence or illustrates floristic relations between Brazilian and Andean Mountains or Central American Mountains.

  20. Tear ferning test in healthy dogs.

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    Oriá, Arianne P; Raposo, Ana Claudia S; Araújo, Nayone L L C; Lima, Felipe B; Masmali, Ali M

    2017-11-07

    To evaluate and compare three tear sampling methods using two grading scales for administering the tear ferning test (TFT) to healthy dogs. In total, 90 dogs (180 eyes) were subjected to tear sampling using millimetered strips, reused after the Schirmer tear test (STT) (Schirmer group, SG). Then, the dogs were subdivided into three groups according to sampling approach: micropipette (MPG), microcapillary (MCG), and Schirmer sample 2 (S2G). The collected tears were dried on a clean microscope glass slide at room temperature and humidity. The ferning patterns were observed under a polarized light microscope and classified according to the Rolando and Masmali grading scales. Although all three methods were feasible, the STT was easier to perform in clinical settings. Type I and Grade 1 were the most commonly observed (64.17% and 61.7%, respectively) regardless of collection method. There was no significant difference between the STT median values and the TFT classifications. The TFT is appropriate for dogs and can be performed using the three suggested sampling methods, with a higher frequency of Type I and Grade 1. Thus, it is possible to use both grading scales in the classification of tear ferning in dogs. © 2017 American College of Veterinary Ophthalmologists.

  1. The fern sporangium: an ultrafast natural catapult

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    Noblin, Xavier; Argentina, Mederic; Westbrook, Jared; Llorens, Coraline; Rojas, Nicolas; Dumais, Jacques

    2012-02-01

    Plants have developed fascinating mechanisms to create ultra fast movements that often reach the upper limit allowed by physical laws. Inspiration for new technologies is one of the reasons for the strong interest for these mechanisms, along with the deep interest of understanding complex, natural systems. The fern sporangium is a capsule that contains the spores, it is surrounded by a row of cells called the annulus which acts as a beam. Due to the water evaporation from its cells, the annulus bends strongly and induces elastic energy storage during an opening phase. The tension in the cells breaks when cavitation bubbles appear in the cells, leading to a fast release of the elastic energy. The fern sporangium then acts as a catapult which ejects rapidly its spores by closing back to the initial closed shape. We have analyzed the slow opening motion and the fast catapulting mechanism. We found that the catapult motion involves two time scales, showing a very original behavior. In man-made catapults, the recoil motion needs to be arrested by a cross bar so that the projectile is released from the arm. We show here that the fern sporangium replaces the essential cross bar by an elegant poroelastic damping, leading to a completely autonomous, efficient device.

  2. Thirteen new records of ferns from Brazil

    Directory of Open Access Journals (Sweden)

    Thais Almeida

    2015-02-01

    Full Text Available Thirteen fern species are reported for the first time for Brazil. Among the new records, eight are from Acre state (Cyathea subincisa, Cyclodium trianae, Elaphoglossum stenophyllum, Hypoderris brauniana, Pleopeltis stolzei, Thelypteris arcana, Thelypteris comosa, Thelypteris valdepilosa, two are from Pará state (Polypodium flagellare, Tectaria heracleifolia, one from Minas Gerais state (Alsophila salvinii, one from Ceará state (Campyloneurum costatum and one from Bahia state (Thelypteris rolandii. Part of the species shows a disjunct occurrence or illustrates floristic relations between Brazilian and Andean Mountains or Central American Mountains.

  3. Distribution and dynamics of hayscented fern following stand harvest

    Science.gov (United States)

    Songlin Fei; Peter J. Gould; Melanie J. Kaeser; Kim C. Steiner

    2008-01-01

    The distribution and dynamics of hayscented fern were examined as part of a large-scale study of oak regeneration in Pennsylvania. The study included 69 stands covering 3,333 acres in two physiographic provinces. Hayscented fern was more widely distributed and occurred at higher densities in the Allegheny Plateau physiographic provinces versus the Ridge and Valley...

  4. Tear ferning in normal dogs and dogs with keratoconjunctivitis sicca ...

    African Journals Online (AJOL)

    Tear ferning in normal dogs and dogs with keratoconjunctivitis sicca. David Williams, Heather Hewitt. Abstract. This study evaluates tear ferning as an ancillary technique for the evaluation of the canine tear film in normal eyes and eyes affected by keratoconjunctivitis sicca (KCS). Thirty dogs with KCS and 50 control dogs ...

  5. A monograph of the fern genus Bolbitis (Lomariopsidaceae)

    NARCIS (Netherlands)

    Hennipman, E.

    1977-01-01

    The present study deals with systematic and taxonomic problems in the acrostichoid fern genus Bolbitis (Lomariopsidaceae). The idea came from Prof. Holttum, Kew, in view of his intended revision of the lomariopsidoid ferns for Flora Malesiana. Originally the study was confined to the Asian

  6. A Catskill Flora and Economic Botany, I: Pteridophyta. The Ferns and Fern Allies. Bulletin No. 438, New York State Museum.

    Science.gov (United States)

    Brooks, Karl L.

    The information contained within this guide about flora of the ferns and fern allies of the Catskill Mountains of New York State covers medical and food uses of the plants, as well as the more typical floristic data of keys, drawings, and plant descriptions. (CS)

  7. The fern sporangium: a unique catapult.

    Science.gov (United States)

    Noblin, X; Rojas, N O; Westbrook, J; Llorens, C; Argentina, M; Dumais, J

    2012-03-16

    Various plants and fungi have evolved ingenious devices to disperse their spores. One such mechanism is the cavitation-triggered catapult of fern sporangia. The spherical sporangia enclosing the spores are equipped with a row of 12 to 13 specialized cells, the annulus. When dehydrating, these cells induce a dramatic change of curvature in the sporangium, which is released abruptly after the cavitation of the annulus cells. The entire ejection process is reminiscent of human-made catapults with one notable exception: The sporangia lack the crossbar that arrests the catapult arm in its returning motion. We show that much of the sophistication and efficiency of the ejection mechanism lies in the two very different time scales associated with the annulus closure.

  8. Some new external flavonoids from American ferns

    Energy Technology Data Exchange (ETDEWEB)

    Wollenweber, E.

    1979-01-01

    American gymnogrammoid ferns have been analysed for the flavonoid aglycones present in frond exudates. They are predominantly methylated chalcones, dihydrochalcones, flavones, and flavonols, occurring mostly as farinose deposit (''ceraceous indument''). This is the first report of external flavonoids on Pterozonium species; a chalcone has been identified. On Cheilanthes kaulfussii and Cheilanthes viscida traces of flavonoid aglycones are observed, dissolved in lipophilic exudate material. On Pellaea longimucronata a flavonol is found even on leaves which appear glaucous. 2',4',6'-Trihydroxychalcone is found for the second time in the plant kingdom on Adiantum sulphureum. Galangin-3,7-dimethylether is found as a new natural flavonol on Cheilanthes kaulfussii. In addition, samples of Pityrogramma chrysoconia and Pit. triangularis var. maxonii have been investigated. The results indicate chemotaxonomic implication of flavonoid patterns.

  9. Fern leaves and cauliflower curds are not fractals.

    Science.gov (United States)

    Lev-Yadun, Simcha

    2012-05-01

    The popular demonstration of drawing a mature fern leaf as expressed by Barnsley's fractal method is mathematically and visually very attractive but anatomically and developmentally misleading, and thus has limited, if any, biological significance. The same is true for the fractal demonstration of the external features of cauliflower curds. Actual fern leaves and cauliflower curds have a very small number of anatomically variable and non-iterating bifurcations, which superficially look self-similar, but do not allow for scaling down of their structure as real fractals do. Moreover, fern leaves and cauliflower curds develop from the inside out through a process totally different from fractal drawing procedures. The above cases demonstrate a general problem of using mathematical tools to investigate or illustrate biological phenomena in an irrelevant manner. A realistic set of mathematical equations to describe fern leaf or cauliflower curd development is needed.

  10. THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

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    Ionica Deliu

    2013-12-01

    Full Text Available The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derived remedies. In this study the antimicrobial effect of methanolic and ethanolic extracts from three fern species were tested. The extracts were gained from gametophytic stage of ferns obtained in vitro. The most obvious effect was observed for Asplenium trichomanes-ramosum extract. The total polyphenols and flavonoids content were established, too.

  11. Mechanics modelling of fern cavitation catapult

    Science.gov (United States)

    Kang, Jingtian; Li, Kai; Tan, Huifeng; Wang, Changguo; Cai, Shengqiang

    2017-12-01

    Cavitation is often regarded as a failure mode in soft materials. An intriguing phenomenon has been recently discovered that fern sporangium can take advantage of drying-induced cavitation instability in annulus cells to disperse spores at an extraordinarily high acceleration. Briefly, the decrease of environmental humidity causes continuous bending of the sporangium and growth of cavities inside the annulus cells, with the elastic energy accumulated in sporangium walls. When the humidity is lower than a critical value, the cavities suddenly expand dramatically inside the cells, causing a quick release of the elastic energy stored in the annular structure. As a result, like a catapult, the sporangium snaps back and ejects the seeds at a high speed. Motivated by the observation, in this article, we study cavitation instability in a similar structure as the sporangium. To simplify the problem, in our model, the mechanics of cells in the sporangium are described by the polymer gel model, while the sporangium wall is modelled as a hyperelastic material. When the environmental humidity is lower than a critical value, through energetic analyses, we can predict the cavitation catapult phenomenon using the model. We hope that our study in this article can provide useful insights into the bio-inspired design of structures which can take advantage of cavitation instability in soft materials.

  12. Is there foul play in the leaf pocket? The metagenome of floating fern

    NARCIS (Netherlands)

    Dijkhuizen, L.W.; Brouwer, P.; Bolhuis, H.; Reichart, G.-J.; Koppers, N.; Huettel, B.; Bolger, A.M.; Li, F.-W.; Cheng, S.; Liu, X.; Wong, G.K.-S.; Pryer, K.; Weber, A.; Bräutigam, A.; Schluepmann, H.

    2018-01-01

    Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolificgrowth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms,the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associatedwith Azolla ferns

  13. FTIR and py-GC-MS spectra of true-fern and seed-fern sphenopterids (Sydney Coalfield, Nova Scotia, Canada, Pennsylvanian)

    Science.gov (United States)

    Zodrow, E.L.; Mastalerz, Maria

    2002-01-01

    Sphenopterid specimens from the Late Pennsylvanian of Sydney Coalfield, Canada, are investigated by FTIR and py-GC-MS techniques as part of an on-going research project into the biochemistry and chemotaxonomy of Pennsylvanian-age pteridophylls. Included in the investigation are samples of the true-fern species Oligocarpia brongniartii and Zeilleria delicatula that are preserved as naturally macerated cuticles (NMC), and the seed-fern Eusphenopteris neuropteroides that is also preserved as a compression/impression. FTIR spectra of NMC seed-fern E. neuropteroides, and fern sphenopterid O. brongniartii are very similar, except that the latter does not have aromatic bands in the 700-900 cm-1 out-of-plane region, py-GC-MS show more aromatic compounds for the seed fern than for the two true-fern sphenopterids. Another difference between seed-fern and true-fern sphenopterids is a lower ratio of CH2 to CH3 in chemically treated specimens (CTC) for the seed fern. These observations suggest slightly higher aromaticity for the seed ferns, perhaps related to some chemotaxonomic differences. Comparison of FTIR and py-GC-MS characteristics of sphenopterids and other plant groups shows that these two techniques have potential to identifying chemotaxonomic signals from Carboniferous pteridophylls in general, although more data are needed to confirm this. ?? 2002 Elsevier Science B.V. All rights reserved.

  14. FTIR and py-GC-MS spectra of true-fern and seed-fern sphenopterids (Sydney Coalfield, Nova Scotia, Canada, Pennsylvanian)

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, P.O. Box 5300, NS B1P 6L2 Sydney, Nova Scotia (Canada); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 N. Walnut Grove, 47405-2208 Bloomington, IN (United States)

    2002-07-01

    Sphenopterid specimens from the Late Pennsylvanian of Sydney Coalfield, Canada, are investigated by FTIR and py-GC-MS techniques as part of an on-going research project into the biochemistry and chemotaxonomy of Pennsylvanian-age pteridophylls. Included in the investigation are samples of the true-fern species Oligocarpia brongniartii and Zeilleria delicatula that are preserved as naturally macerated cuticles (NMC), and the seed-fern Eusphenopteris neuropteroides that is also preserved as a compression/impression. FTIR spectra of NMC seed-fern E. neuropteroides, and fern sphenopterid O. brongniartii are very similar, except that the latter does not have aromatic bands in the 700-900 cm{sup -1} out-of-plane region. py-GC-MS show more aromatic compounds for the seed fern than for the two true-fern sphenopterids. Another difference between seed-fern and true-fern sphenopterids is a lower ratio of CH{sub 2} to CH{sub 3} in chemically treated specimens (CTC) for the seed fern. These observations suggest slightly higher aromaticity for the seed ferns, perhaps related to some chemotaxonomic differences. Comparison of FTIR and py-GC-MS characteristics of sphenopterids and other plant groups shows that these two techniques have potential to identifying chemotaxonomic signals from Carboniferous pteridophylls in general, although more data are needed to confirm this.

  15. Identification of carcinogenic tannin isolated from Bracken fern (Pteridium aquilinum).

    Science.gov (United States)

    Wang, C Y; Chiu, C W; Pamukcu, A M; Bryan, G T

    1976-01-01

    We attempted to isolate a carcinogenic substance from bracken fern (Pteridium aquilinum), a naturally occurring toxicant responsible for the production of chronic enzootic hematuria and urinary bladder cancer of cattle and carcinogenic for various target organs of several species. Hot methanol extracts of bracken fern were solubilized in water and extracted with chloroform followed by a mixture of n-butanol-butanone (1:1). That fraction was dried and triturated with ether-methanol (4:1), n-butanol, and finally absolute ethanol. The insoluble residue was dissolved in 10% aqueous methanol and passed through Dowex 1 OH-, Dowex 50 H+, or Dowex 1 OH- and then Dowex 50 H+ ion exchange resins. A condensed tannin, isolated from one ot the fractions, was identical to that isolated from bracken fern by the caffeine procedure used for the separation of tannins from other plant constituents. Three systems were used for bioassay; induction of bladder carcinoma by implantation of cholesterol pellets containing bracken fern fractions into the bladder lumens of mice; acute toxicity by ip injection of brachen fern fraction into mice; and growth inhibition of Escherichia coli. The following fractions induced significantly greater incidences of bladder carcinoma than did cholesterol pellets only: tannin, Dowex 50 H+, residue, n-butanol, and methanol. Tiliroside, a component of bracken fern fractions into the bladder lumens of mice; acute genic acid, and quercetin were not carcinogenic. Tannin was the most toxic (mean lethal dose: 0.16 mg/g) and carcinogenic. None of the carcinogenic fractions inhibited growth of E. coli.

  16. El historiador Fernández de Piedrahita

    Directory of Open Access Journals (Sweden)

    Carlos López Narváez

    1964-10-01

    Full Text Available Varón de Dios, las letras y la patria, Lucas Fernández de Piedrahita nació en Santafé de Bogotá, el 6 de marzo de 1624, de hidalgo linaje por su padre español, y de principesca sangre materna, como que su progenitora, doña Catalina Collantes, esposa de don Domingo Fernández de Soto y Piedrahita, era nieta de doña Francisca Coya de la realeza inca del Perú.

  17. In vitro mutagenesis of commercial fern, Asplenium nidus from spores

    International Nuclear Information System (INIS)

    Norazlina Noordin

    2004-01-01

    Asplenium is a largest, most diverse fern genera. One of the common species is Asplenium nidus, well known as Bird's-nest fern, a medium to large fern with erect, stout, unbranched rhizomes. In creating variability of ferns for the benefit of the ornamental plant industry, in vitro mutagenesis is used. In this study, spores of Asplenium nidus were collected from frond bearing mature sporangia. Spores were cultured in modified 1/2 MS basal medium supplemented with various combinations of 6-Benzylaminopurine (BAP) and Naphtalene Acetic Acid (NAA). Spore cultures were incubated in incubation room at 24 degree C with 16 hours photoperiod (3500 lux). It was found that, the most effective combinations were 1 mg/1 BAP + 0. 1 mg/1 NAA and 2mg/1 BAP + 0. 1 mg/1 NAA. Prothallus was formed after 10 days of cultures and gametophytes were formed 1 month later. These gametophytes were irradiated with Gamma ray at doses of 0, 20, 90, 120, 150 and 180 Gy. From the preliminary result obtained from this study, for generating variations and desired phenotypic expression for Asplenium nidus, recommended doses for in vitro mutagenesis using spores are between 90 Gy to 150 Gy. Gametophytes were subcultured at monthly interval to ensure further development and propagation. Frequent monitoring for any changes in the morphology of the irradiated Asplenium nidus plants were carried out. (Author)

  18. Limitation of distribution of two rare ferns in fragmented landscape

    Czech Academy of Sciences Publication Activity Database

    Tájek, P.; Bucharová, Anna; Münzbergová, Zuzana

    2011-01-01

    Roč. 37, č. 5 (2011), s. 495-502 ISSN 1146-609X R&D Projects: GA MŠk 2B06178 Institutional research plan: CEZ:AV0Z60050516 Keywords : ferns * spores * dispersal Subject RIV: EF - Botanics Impact factor: 1.570, year: 2011

  19. Comparative morphology of the gametophyte of some Thelypteroid ferns

    NARCIS (Netherlands)

    Sen, Tuhinsri

    1981-01-01

    A study of the development of the gametophytes of sixteen thelypteroid ferns reveals similarities and significant differences among them. Combinations of the diversified features of the prothalli appear to have a tremendous impact on identification and delimitation of the major taxa, and support the

  20. Ferns and lycophytes of Pernambuco State, Brazil: Metaxyaceae

    Directory of Open Access Journals (Sweden)

    Iva Carneiro Leão Barros

    2010-09-01

    Full Text Available The present paper elucidates part of the fern flora of Pernambuco State. Metaxyaceae is native to the state and is represented by a single species, Metaxya rostrata (Kunth C. Presl. Descriptions and illustrations, as well as geographical distribution and habitats, are presented.

  1. Reproductive potentials of a tropical fern Cyclosorus afer (Christ ...

    African Journals Online (AJOL)

    Reroductive potentials of Cyclosorus afer (Christ.) Ching a tropical fern was studied. Propagation by the spores of this plant was therefore investigated. The aim was to determine the ability of early germination of these spores using nutrient (growth) agar. The experimental site was the Reforestation unit of the Department of ...

  2. Homoeologous Heterozygosity and Recombination in the Fern Pteridium aquilinum.

    Science.gov (United States)

    Chapman, R H; Klekowski, E J; Selander, R K

    1979-06-15

    The bracken fern, Pteridium aquilinum, which can form completely homozygous zygotes in a single generation of self-fertilization, has a genetic system that allows the storage and release of genetic variability in spite of this homozygosity. Analysis of the distribution of electrophoretically demonstrable genetic markers demonstrates that this system is based on recombination between duplicated, unlinked loci.

  3. First megafossil evidence of Cyatheaceous tree fern from the Indian ...

    Indian Academy of Sciences (India)

    A part of the compressed tree fern axis with leaf and adventitious root scars in unusual arrangement from. Plio–Pleistocene sediments of Arunachal Pradesh, India is described as Cyathea siwalika sp. nov. This record suggests that Cyathea was an important component of tropical evergreen forest in the area during.

  4. Optimization of protein extraction from fern frond using Response ...

    African Journals Online (AJOL)

    Protein extractability from Nephrolepis biserrata and Arthropteris orientalis was studied under various conditions. The extraction of fern protein was conducted using alkaline, alcohol and saline treatments under various conditions of treatment concentrations and time of agitation. Central composite design of Response ...

  5. Instructions for collecting tree ferns of the family Cyatheaceae

    NARCIS (Netherlands)

    Holttum, R.E.

    1957-01-01

    The next monographic study which will be undertaken for the series Pteridophyta of the Flora Malesiana will be devoted to the tree ferns of the Cyatheaceae. In connection with the large size of these plants and the desirability of having more and complete material at our disposal, the following

  6. New fern records for Kilimanjaro | Hemp | Journal of East African ...

    African Journals Online (AJOL)

    Working on the flora and vegetation of Mt Kilimanjaro, Tanzania, 17 ferns in 10 families were found that had not yet been recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum raddianum, Asplenium bugoiense, Blechnum ivohibense, Blotiella stipitata, Dryopteris ...

  7. Three new fern records for Kilimanjaro | Hemp | Journal of East ...

    African Journals Online (AJOL)

    Working on the flora and vegetation of Mt. Kilimanjaro, Tanzania, three ferns in three families were found that are not yet recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum reniforme, Azolla africana and Trichomanes radicans. Journal of East African Natural History ...

  8. The colonisation of woodland gaps by ferns and horsetails

    NARCIS (Netherlands)

    Bremer, P.

    2010-01-01

    In the Voorsterbos, a planted woodland on a former sea-floor (the Netherlands), artificial gaps within stands of Fagus sylvatica on boulder clay were monitored for five or six years after cutting. Ten fern species and three species of horsetail established in these gaps, with Dryopteris cristata,

  9. Stasis and convergence characterize morphological evolution in eupolypod II ferns.

    Science.gov (United States)

    Sundue, Michael A; Rothfels, Carl J

    2014-01-01

    Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of

  10. A 4000-species dataset provides new insight into the evolution of ferns.

    Science.gov (United States)

    Testo, Weston; Sundue, Michael

    2016-12-01

    Ferns are the second-most diverse lineage of vascular plants on Earth, yet the best-sampled time-calibrated phylogeny of the group to date includes fewer than 5% of global diversity and was published seven years ago. We present a time-calibrated phylogeny that includes nearly half of extant fern diversity. Our results are evaluated in the context of previous studies and the fossil record, and we develop new hypotheses about the radiation of leptosporangiate ferns. We used sequence data from six chloroplast regions for nearly 4000 species of ferns to generate the most comprehensive phylogeny of the group ever published. We calibrate the phylogeny with twenty-six fossils and use an array of phylogenetic methods to resolve phylogenetic relationships, estimate divergence times, and infer speciation, extinction, and net diversification rates. We infer a mid-late Silurian origin for ferns (including horsetails) and an early Carboniferous origin for leptosporangiate ferns. Most derived fern families appeared in the Cretaceous and persisted for millions of years before rapidly diversifying in the Cenozoic. We find no evidence of differential rates of diversification among terrestrial and epiphytic species. Our findings challenge previous hypotheses on the evolutionary history of ferns and present a new paradigm for their Cenozoic radiation. We estimate earlier divergences for most fern lineages than were reported in previous studies and provide evidence of extended persistence of major fern lineages prior to rapid diversification in the last fifty million years. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Isolation of an active glucoside in bracken fern, Pteridium aquilinum.

    Science.gov (United States)

    Saito, T; Kirihara, Y; Ishii, K

    1984-08-01

    An active glucoside that enhanced release of histamine from rat peritoneal mast cells was isolated from a toxic fraction of bracken fern, Pteridium aquilinum, by partition column chromatography on Sephadex G-25. It was a yellowish amorphous powder on freeze-drying, readily soluble in water or ethanol, and insoluble in ether. It was hydrolysed with beta-glucosidase to release D-glucose. It was assumed to be a kind of beta-glucopyranoside with a carbocyclic structure in the aglycone moiety.

  12. ASSIMILATORY PIGMENTS CONTENT IN FERN GAMETOPHYTES AND SPOROPHYTES

    Directory of Open Access Journals (Sweden)

    Monica Popescu

    2012-04-01

    Full Text Available Pteridophytes distinguishes from other land plants is that they have independent gametophyte and sporophyte generations. Half fern’s lives are spent in the gametophyte stage, or haplophase, and the other half in the sporophyte stage. Fern gametophytes have no vascular system, like bryophytes, and live on substrate surfaces as small individual plants, but their sporophytes have a vascular system enabling more vertical growth than gametophytes, resulting in a large herbaceous plant form. Many species are able to change the composition of their photosynthetic apparatus to optimize photosynthesis for the light environment in which they are growing. Measurements performed at fern gametophytes (Polypodium vulgare, Asplenium trichomanes and Cystopteris fragilis obtained in vitro and in fern sporophytes (ten species from the natural site showed that the content of chlorophylls is both qualitatively and quantitatively similar to that of higher plants. Chlorophyll content was much higher in sporophytes, which is in agreement with their higher photosynthetic rates. The highest amount of chlorophyll values was determined to species of Asplenium, and the lower value was in Lycopodium clavatum.

  13. Ferns: the missing link in shoot evolution and development

    Directory of Open Access Journals (Sweden)

    Andrew Robert George Plackett

    2015-11-01

    Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

  14. Limitation of distribution of two rare ferns in fragmented landscape

    Science.gov (United States)

    Tájek, Přemysl; Bucharová, Anna; Münzbergová, Zuzana

    2011-09-01

    Species distribution in the landscape is limited either by 1. diaspore production, dispersal and establishment abilities or 2. by availability of suitable habitats; 3. or by a combination of both factors. The relative importance of these factors is species-dependent and has mainly been studied for seed plants. We studied the importance of habitat and dispersal limitation for distribution of two rare fern species, Asplenium adulterinum and Asplenium cuneifolium, restricted to serpentine rocks, using analysis of their distribution on a regional scale (several kilometers). Within the model region, all 98 serpentine rocks were mapped. We used data on abiotic characteristics and on the presence of all vascular plant species on the rocks to predict which of the rocks were suitable for the two Asplenium species. Suitable habitats were positively defined mainly by the presence of appropriate microhabitats and the height of the highest rock, which represents the size of space with lowered concurrence. Other determinants of habitat suitability differed between species. Neither species occupied all suitable localities, indicating dispersal limitation. Locality isolation significantly affected one of the species but not the other. Overall, the results suggest that both fern species have suitable but unoccupied localities in the region and demonstrates that ferns, similar to seed plants, are limited by their dispersal ability in the landscape.

  15. Morphology, Physiology, and Anatomy of Penny Fern (Drymoglossum phyloselloidesand Its Effect on Cocoa

    Directory of Open Access Journals (Sweden)

    Fitria Yuliasmara

    2013-08-01

    Full Text Available This study aims to determine the anatomy, physiology and morphology of penny fern (Drimoglosum phylloseloides and its effect on cocoa. Morphological observation of penny fern used microscope to observe the roots, stems, leaves and spores. Physiology of penny fern was observed based on number of stomata and stomatal conductance using stomata printing method, while the amount of chlorophyll based on spectrophotometric method and rate of transpiration used cobalt chloride paper. Penny fern anatomy on cross-sectional and longitudinal in roots, stems and leaves. Penny fern growth was observed based the length of tendrils once a week during rainy and dry season. While the effect of penny fern invasion was observed based on variable leaf area with gravimetric method, the cross-section of attacked cacao branch using microtom and microscope and chlorophyll content by chlorophyll meter. Results showed that penny fern is a epiphytic weed which was crassulaceae acid metabolism plants that have the ability to absorb carbon dioxide at night and carry out photosynthesis during the day with closed stomata. Penny ferns reproduce using spores. The growth rate of penny fern 2.18 cm/week during the dry season and while in rainy season 3.89 cm/week. Penny fern leaf contains 0.0212 mg/g chlorophyll. Penny fern stomata density was 18.33/mm 2 with a width of opening stomata at night 26.3 µm which caused a veryslow rate of transpiration of 0.69 mm 2 /seconds. The existence penny fern on cocoa decreased leaf area and chlorophyll content decreased crop productivity which was indicated by decreasing in number of flowers, number of small, medium fruit, and large pods. However it had no effect on the number of leaves on one side flush cocoa. Key words: Drimoglosum phylloseloides, weeds, decrease productivity, Theobroma cacao

  16. Effect of synthetic detergents on germination of fern spores

    Energy Technology Data Exchange (ETDEWEB)

    Devi, Y.; Devi, S.

    1986-12-01

    Synthetic detergents constitute one of the most important water pollutants by contaminating the lakes and rivers through domestic and industrial use. Considerable information is now available for the adverse effects of detergents an aquatic fauna including fish, algae, and higher aquatic plants. Marked inhibition of germination in orchids and brinjals and of seedlings growth in raddish suggest that rapidly growing systems could be sensitive to detergent polluted water. The present study of the effect of linear alkyl benzene sulphonate on germination of the spores of a fern, Diplazium esculentum aims at the understanding of the effects of water pollution on pteridophytes and the development of spore germination assay for phytoxicity evaluation.

  17. Fast segmentation of kidney components using random forests and ferns.

    Science.gov (United States)

    Jin, Chao; Shi, Fei; Xiang, Dehui; Zhang, Lichun; Chen, Xinjian

    2017-12-01

    This paper studies the feasibility of developing a fast and accurate automatic kidney component segmentation method. The proposed method segments the kidney into four components: renal cortex, renal column, renal medulla, and renal pelvis. In this article, we have proposed a highly efficient approach which strategically combines random forests and random ferns methods to segment the kidney into four components: renal cortex, renal column, renal medulla, and renal pelvis. The proposed method is designed following a coarse-to-fine strategy. The initial segmentation applies random forests and random ferns with a variety of features, and combines their results to obtain a coarse renal cortex region. Then the fine segmentation of four kidney components is achieved using the weighted forests-ferns approach with the well-designed potential energy features which are calculated based on the initial segmentation result. The proposed method was validated on a dataset with 37 contrast-enhanced CT images. Evaluation indices including Dice similarity coefficient (DSC), true positive volume fraction (TPVF), and false positive volume fraction (FPVF) are used to assess the segmentation accuracy. The proposed method was implemented and tested on a 64-bit system computer (Intel Core i7-3770 CPU, 3.4 GHz and 8 GB RAM). The experimental results demonstrated the high accuracy and efficiency for segmenting the kidney components: the mean Dice similarity coefficients were 89.85%, 80.60%, 86.63%, and 77.75% for renal cortex, column, medulla, and pelvis, respectively, for right and left kidneys. The computational time of segmenting the whole kidney into four components was about 3 s. The experimental results showed the feasibility and efficacy of the proposed automatic kidney component segmentation method. The proposed method applied an efficient weighted strategy to combine random forests and ferns, making full use of the advantages of both methods. The novel potential energy features help

  18. A Gompertz regression model for fern spores germination

    Directory of Open Access Journals (Sweden)

    Gabriel y Galán, Jose María

    2015-06-01

    Full Text Available Germination is one of the most important biological processes for both seed and spore plants, also for fungi. At present, mathematical models of germination have been developed in fungi, bryophytes and several plant species. However, ferns are the only group whose germination has never been modelled. In this work we develop a regression model of the germination of fern spores. We have found that for Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei and Polypodium feuillei species the Gompertz growth model describe satisfactorily cumulative germination. An important result is that regression parameters are independent of fern species and the model is not affected by intraspecific variation. Our results show that the Gompertz curve represents a general germination model for all the non-green spore leptosporangiate ferns, including in the paper a discussion about the physiological and ecological meaning of the model.La germinación es uno de los procesos biológicos más relevantes tanto para las plantas con esporas, como para las plantas con semillas y los hongos. Hasta el momento, se han desarrollado modelos de germinación para hongos, briofitos y diversas especies de espermatófitos. Los helechos son el único grupo de plantas cuya germinación nunca ha sido modelizada. En este trabajo se desarrolla un modelo de regresión para explicar la germinación de las esporas de helechos. Observamos que para las especies Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei y Polypodium feuillei el modelo de crecimiento de Gompertz describe satisfactoriamente la germinación acumulativa. Un importante resultado es que los parámetros de la regresión son independientes de la especie y que el modelo no está afectado por variación intraespecífica. Por lo tanto, los resultados del trabajo muestran que la curva de Gompertz puede representar un modelo general para todos los helechos leptosporangiados

  19. Crowdfunding the Azolla fern genome project: a grassroots approach.

    Science.gov (United States)

    Li, Fay-Wei; Pryer, Kathleen M

    2014-01-01

    Much of science progresses within the tight boundaries of what is often seen as a "black box". Though familiar to funding agencies, researchers and the academic journals they publish in, it is an entity that outsiders rarely get to peek into. Crowdfunding is a novel means that allows the public to participate in, as well as to support and witness advancements in science. Here we describe our recent crowdfunding efforts to sequence the Azolla genome, a little fern with massive green potential. Crowdfunding is a worthy platform not only for obtaining seed money for exploratory research, but also for engaging directly with the general public as a rewarding form of outreach.

  20. Spatial Characteristics of Edible Wild Fern Harvesting in Mountainous Villages in Northeastern Japan Using GPS Tracks

    Directory of Open Access Journals (Sweden)

    Toshiya Matsuura

    2014-02-01

    Full Text Available Wild plants in forests provide valuable living resources for rural communities. The location where local people harvest various species is important to the wise use of forest ecosystem services. Using global positioning system (GPS tracking of harvesters’ activities as well as geographic information system (GIS and a generalized linear model (GLM, this study analyzed the spatial differences among harvesting sites of three popular edible ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous villages of Northeastern Japan. The explanatory variables used were vegetation classes, terrain features, and proximity to roadways. The GLM yielded clear differences in harvesting sites among species that were affected by both the species’ ecological characteristics and human behavior. Ostrich fern was harvested mainly in canopy openings along valley floors, whereas royal fern harvest sites were frequently located in snow avalanche scrublands. Bracken was mainly harvested in deforested areas or young conifer plantations. Whereas ostrich fern and bracken harvest sites were restricted by the accessibility from roadways, this was not the case for royal fern. Potential harvest sites of ferns were estimated with the highest value for bracken. Our results suggest that local harvesters seriously consider various natural and anthropogenic factors to maintain effective and sustainable harvesting.

  1. The mucilage secreting hairs on the young fronds of some Leptosporangiate Ferns

    NARCIS (Netherlands)

    Hennipman, E.

    1968-01-01

    During a collecting trip to Thailand, as a member of the Thai-Dutch botanical expedition 1965/1966, I was struck by the excessive amount of mucilage sometimes present on the circinnate fronds of several leptosporangiate ferns. This was especially evident in representatives of the monotypic fern

  2. Asplenium bird’s nest ferns in rainforest canopies are climate-contingent refuges for frogs

    Directory of Open Access Journals (Sweden)

    Brett R. Scheffers

    2014-12-01

    Full Text Available Epiphytes are important for canopy dwelling organisms because they provide a cool and moist microhabitat in the relatively hot and dry canopy. Here we examine whether epiphytic Asplenium ferns act as important habitats for arboreal frogs. We conducted extensive fern and habitat surveys for frogs in the Philippines, and complimented these surveys with roaming day and night canopy surveys to identify the full extent of habitat use across the vertical strata. We artificially dried ferns of various sizes to identify relationships between water and temperature buffering. Ferns are the preferred diurnal microhabitat and breeding habitat for arboreal frogs. A strong positive relationship exists between fern size and frog usage and abundance. Our drying experiments show that large ferns buffer maximum temperatures and reduce variability in temperatures, and buffering is directly linked to their hydration. Frogs are likely using large ferns for their moist, cool, environments for breeding and daytime retreat, which supports the buffered microhabitat hypothesis—these plants promote species coexistence through habitat creation and amelioration of physical stress. However, drying experiments suggest that this buffering is contingent on regular rainfall. Altered rainfall regimes could lead to the unexpected loss of the functional capacity of these important fern habitats. Keywords: Climate change, Functionality, Microhabitat, Refuge, Ectotherm, Precipitation

  3. 76 FR 45649 - Notice of Final Federal Agency Actions on I-5: Fern Valley Interchange Project: Jackson County, OR

    Science.gov (United States)

    2011-07-29

    ... the OR99/Fern Valley intersection will be improved. East of the interchange, North Phoenix Road will... on I-5: Fern Valley Interchange Project: Jackson County, OR AGENCY: Federal Highway Administration... proposed highway project, I-5: Fern Valley Interchange in Jackson County, Oregon. This action grants...

  4. The effect of nitrogen additions on bracken fern and its insect herbivores at sites with high and low atmospheric pollution

    Science.gov (United States)

    M.E. Jones; M.E. Fenn; T.D. Paine

    2011-01-01

    The impact of atmospheric pollution, including nitrogen deposition, on bracken fern herbivores has never been studied. Bracken fern is globally distributed and has a high potential to accumulate nitrogen in plant tissue. We examined the response of bracken fern and its herbivores to N fertilization at a high and low pollution site in forests downwind of Los Angeles,...

  5. In Vitro Conservation of Some Threatened and Economically Important Ferns Belonging to the Indian Subcontinent

    Directory of Open Access Journals (Sweden)

    Shastri P. Shukla

    2014-01-01

    Full Text Available This study was undertaken to identify methods of mass multiplication for five ornamental, economically important ferns (Nephrolepis biserrata (Sw. Schott., N. cordifolia cv. ‘‘duffii’’ (L. Presl., N. exaltata cv. bostoniensis (L. Schott., Pteris vittata L., and Cyclosorus dentatus Link., and three threatened ferns, namely, Cyathea spinulosa Wall. ex. Hook, Pityrogramma calomelanos (L. Link., and Microsorum punctatum (L. Schott., through in vitro techniques. Collections were made from different biodiversity zones of India including Northeast Himalayas, Kumaon Himalayas, and Western Ghat and successfully introduced and grown in a fern-house. Aseptic cultures were raised at the morphogenic level of callus, axillary shoot, multiple shoot, and rooted plants. An optimized medium is described for each fern species. Plantlets were also produced from spore culture of Cyathea spinulosa and successfully hardened under fern house conditions.

  6. Ultrasonic synthesis of fern-like ZnO nanoleaves and their enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Qing Lan [School of Mathematics and Physics, Changzhou University, Jiangsu 213164 (China); School of Electronics and Information, Nantong University, Jiangsu 226019 (China); Xiong, Rui [School of Physics and Technology, Wuhan University, Hubei 430072 (China); Zhai, Bao-gai [School of Mathematics and Physics, Changzhou University, Jiangsu 213164 (China); Huang, Yuan Ming, E-mail: dongshanisland@126.com [School of Mathematics and Physics, Changzhou University, Jiangsu 213164 (China)

    2015-01-01

    Graphical abstract: - Highlights: • Fern-like ZnO nanoleaves were synthesized by ultrasonicating Zn microcrystals in water. • A fern-like ZnO nanoleaf is a self-assembly of ZnO nanoplates along one ZnO nanorod. • Fern-like ZnO nanoleaves exhibit enhanced photocatalytic activity than ZnO nanocrystals. • The branched hierarchical structures are responsible for the enhanced photocatalytic activity. - Abstract: Two-dimensional fern-like ZnO nanoleaves were synthesized by ultrasonicating zinc microcrystals in water. The morphology, crystal structure, optical property and photocatalytic activity of the fern-like ZnO nanoleaves were characterized with scanning electron microscopy, X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy and ultraviolet–visible spectroscopy, respectively. It is found that one fern-like ZnO nanoleaf is composed of one ZnO nanorod as the central trunk and a number of ZnO nanoplates as the side branches in opposite pairs along the central ZnO nanorod. The central ZnO nanorod in the fern-like nanoleaves is about 1 μm long while the side-branching ZnO nanoplates are about 100 nm long and 20 nm wide. Further analysis has revealed that ZnO nanocrystals are the building blocks of the central ZnO nanorod and the side-branching ZnO nanoplates. Under identical conditions, fern-like ZnO nanoleaves exhibit higher photocatalytic activity in photodegrading methyl orange in aqueous solution than spherical ZnO nanocrystals. The first-order photocatalytic rate constant of the fern-like ZnO nanoleaves is about four times as large as that of the ZnO nanoparticles. The branched architecture of the hierarchical nanoleaves is suggested be responsible for the enhanced photocatalytic activity of the fern-like ZnO nanoleaves.

  7. Gametophyte ecology and demography of epiphytic and terrestrial tropical ferns.

    Science.gov (United States)

    Watkins, James E; Mack, Michelle K; Mulkey, Stephen S

    2007-04-01

    Factors that influence the distribution of ferns are poorly understood and likely reflect the ecology of both the sporophyte and the gametophyte generation. Little study has been done on the ecology of the gametophyte generation, especially in regard to tropical species. The goal of this study was to examine demography and the influence of light and disturbance on the distribution of the gametophytes of several tropical epiphytic, hemiepiphytic, and terrestrial fern species. Through a series of observational and experimental studies, we found that increased terrestrial gametophyte density and richness were related to both increased light and disturbance. By contrast, increased light had no influence, and increased disturbance negatively affected epiphytic density. Over a 25-mo demographic study, epiphytic and hemiepiphytic species had significantly greater longevities and lower recruitment rates than terrestrial species. Such unique strategies may have evolved in response to different disturbance regimens between the two habitats. Terrestrial species encounter and are adapted to more frequent disturbance and have invested in rapid gametophyte growth and recruitment. Epiphytic species may be more influenced by bryophyte competition, and in habitats of relatively low disturbance, they have invested in greater size and longevities. In such systems, gametophytes are able to survive for years waiting for favorable recruitment conditions.

  8. Horizontal transfer of an adaptive chimeric photoreceptor from bryophytes to ferns.

    Science.gov (United States)

    Li, Fay-Wei; Villarreal, Juan Carlos; Kelly, Steven; Rothfels, Carl J; Melkonian, Michael; Frangedakis, Eftychios; Ruhsam, Markus; Sigel, Erin M; Der, Joshua P; Pittermann, Jarmila; Burge, Dylan O; Pokorny, Lisa; Larsson, Anders; Chen, Tao; Weststrand, Stina; Thomas, Philip; Carpenter, Eric; Zhang, Yong; Tian, Zhijian; Chen, Li; Yan, Zhixiang; Zhu, Ying; Sun, Xiao; Wang, Jun; Stevenson, Dennis W; Crandall-Stotler, Barbara J; Shaw, A Jonathan; Deyholos, Michael K; Soltis, Douglas E; Graham, Sean W; Windham, Michael D; Langdale, Jane A; Wong, Gane Ka-Shu; Mathews, Sarah; Pryer, Kathleen M

    2014-05-06

    Ferns are well known for their shade-dwelling habits. Their ability to thrive under low-light conditions has been linked to the evolution of a novel chimeric photoreceptor--neochrome--that fuses red-sensing phytochrome and blue-sensing phototropin modules into a single gene, thereby optimizing phototropic responses. Despite being implicated in facilitating the diversification of modern ferns, the origin of neochrome has remained a mystery. We present evidence for neochrome in hornworts (a bryophyte lineage) and demonstrate that ferns acquired neochrome from hornworts via horizontal gene transfer (HGT). Fern neochromes are nested within hornwort neochromes in our large-scale phylogenetic reconstructions of phototropin and phytochrome gene families. Divergence date estimates further support the HGT hypothesis, with fern and hornwort neochromes diverging 179 Mya, long after the split between the two plant lineages (at least 400 Mya). By analyzing the draft genome of the hornwort Anthoceros punctatus, we also discovered a previously unidentified phototropin gene that likely represents the ancestral lineage of the neochrome phototropin module. Thus, a neochrome originating in hornworts was transferred horizontally to ferns, where it may have played a significant role in the diversification of modern ferns.

  9. THE DIVERSITY OF EPIPHYTIC FERN ON THE OIL PALM TREE (Elaeis guineensis Jacq.) IN PEKANBARU, RIAU

    OpenAIRE

    Nery Sofiyanti

    2015-01-01

    Oil palm (Elaeis guineensis) is one  main commodity in Riau Province. Morphologically, the trunk of oil palm  has suitable environment for the growth of epiphytic fern, due to its broaden base of petiole that may accumulate organic and anorganic debrish. The objective of this study was to investigate the diversity of epiphytic fern on the oil palm tree. A total of 125 oil palm trees from seven  study sites in Pekanbaru, Riau were observed. The number of epiphytic ferns identified in this stud...

  10. THE DIVERSITY OF EPIPHYTIC FERN ON THE OIL PALM TREE (Elaeis guineensis Jacq. IN PEKANBARU, RIAU

    Directory of Open Access Journals (Sweden)

    Nery Sofiyanti

    2015-02-01

    Full Text Available Oil palm (Elaeis guineensis is one  main commodity in Riau Province. Morphologically, the trunk of oil palm  has suitable environment for the growth of epiphytic fern, due to its broaden base of petiole that may accumulate organic and anorganic debrish. The objective of this study was to investigate the diversity of epiphytic fern on the oil palm tree. A total of 125 oil palm trees from seven  study sites in Pekanbaru, Riau were observed. The number of epiphytic ferns identified in this study was 16 species belongs to six families.

  11. Variation of desiccation tolerance and longevity in fern spores.

    Science.gov (United States)

    Ballesteros, Daniel; Hill, Lisa M; Walters, Christina

    2017-04-01

    This work contributes to the understanding of plant cell responses to extreme water stress when it is applied at different intensity and duration. Fern spores are used to explore survival at relative humidity (RH)moisture level. A RH of 10-25% corresponds well to sorption behavior parameters and is below the glass transition, measured using differential scanning calorimetry. Though response to RH was similar among species, the kinetics of deterioration varied considerably among species and this implies differences in the structure or mobility of molecules within the solidified cytoplasm. Our work suggests that desiccation damage occurs in desiccation tolerant cells, and that it is expressed as a time-dependent response, otherwise known as aging. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. Environmental Fate and Analysis of Ptaquiloside from the Bracken Fern

    DEFF Research Database (Denmark)

    Clauson-Kaas, Frederik

    The naturally occurring phytotoxin ptaquiloside (PTA) has long been known to be both acute toxic and carcinogenic. Contents of more than 1% ptaquiloside on dry weight has been detected in bracken (Pteridium spp.), a fern distributed across the globe in often dense populations. This work focused......H and temperature governed the stability of PTA, with fast decomposition at pH extremes and/or high temperatures. At slightly acidic pH and at temperatures relevant for groundwater, PTA may be stable for months. The effect of standard water treatment procedures has not yet been explored, and dilution from non......-bracken areas will generally limit the risk of human exposure where water is sourced from larger catchments....

  13. The fern cavitation catapult: mechanism and design principles.

    Science.gov (United States)

    Llorens, C; Argentina, M; Rojas, N; Westbrook, J; Dumais, J; Noblin, X

    2016-01-01

    Leptosporangiate ferns have evolved an ingenious cavitation catapult to disperse their spores. The mechanism relies almost entirely on the annulus, a row of 12-25 cells, which successively: (i) stores energy by evaporation of the cells' content, (ii) triggers the catapult by internal cavitation, and (iii) controls the time scales of energy release to ensure efficient spore ejection. The confluence of these three biomechanical functions within the confines of a single structure suggests a level of sophistication that goes beyond most man-made devices where specific structures or parts rarely serve more than one function. Here, we study in detail the three phases of spore ejection in the sporangia of the fern Polypodium aureum. For each of these phases, we have written the governing equations and measured the key parameters. For the opening of the sporangium, we show that the structural design of the annulus is particularly well suited to inducing bending deformations in response to osmotic volume changes. Moreover, the measured parameters for the osmoelastic design lead to a near-optimal speed of spore ejection (approx. 10 m s(-1)). Our analysis of the trigger mechanism by cavitation points to a critical cavitation pressure of approximately -100 ± 14 bar, a value that matches the most negative pressures recorded in the xylem of plants. Finally, using high-speed imaging, we elucidated the physics leading to the sharp separation of time scales (30 versus 5000 µs) in the closing dynamics. Our results highlight the importance of the precise tuning of the parameters without which the function of the leptosporangium as a catapult would be severely compromised. © 2016 The Author(s).

  14. A trinorsesterterpene glycoside from te North American fern Woodwardia virginica (L.) Smith

    Czech Academy of Sciences Publication Activity Database

    Hanuš, L. O.; Řezanka, Tomáš; Dembitsky, V. M.

    2003-01-01

    Roč. 63, - (2003), s. 869-875 ISSN 0031-9422 Institutional research plan: CEZ:AV0Z5020903 Keywords : trinorsesterterpene * glycoside * american fern Subject RIV: EE - Microbiology, Virology Impact factor: 1.889, year: 2003

  15. Using a Microscale Approach to Rapidly Separate and Characterize Three Photosynthetic Pigment Species from Fern

    Science.gov (United States)

    Ayudhya, Theppawut Israsena Na; Posey, Frederick T.; Tyus, Jessica C.; Dingra, Nin N.

    2015-01-01

    A rapid separation of three photosynthetic pigments (chlorophyll "a" and "b" and xanthophyll) from fern ("Polystichum acrostichoides") is described using microscale solvent extraction and traditional thin layer chromatography that minimizes use of harmful chemicals and lengthy procedures. The experiment introduces…

  16. Validity of the saliva ferning test for the diagnosis of dry mouth in Sjögren's syndrome.

    Science.gov (United States)

    el-Miedany, Y M; el-Hady, S M; el-Baddin, M A

    1999-02-01

    To study the validity of saliva ferning patterns as a diagnostic test for dry mouth in primary or secondary Sjogren's Syndrome (SS). Salivary smears were collected from 25 patients with Sjögren's syndrome in the fasting and nonfasting state. All 25 patients had symptomatic xerostomia and xerophthalmia and a positive Shirmer's test. Smears were taken from four sites, the cheek, lower lip, tongue, and saliva. Tests were done for rheumatoid factor, antinuclear antibodies, and anti-Ro(SS-A) antibodies. The salivary smears were air-dried and examined under a light and a polarizing microscope. Smears from 25 healthy subjects were also examined as controls. Three patterns of salivary secretion were identified, namely normal geometric ferning, reindeer antler ferning, and thick branching ferning. All Sjögren's syndrome patients had abnormal salivary smears, usually with a combination of reindeer antler ferning, thick branching ferning, and mucosal squames. This combination was seen in six of the 25 fasting specimens (24%); most of the remaining fasting samples showed the reindeer antler ferning. Reindeer antler ferning alone was found in five fasting and four nonfasting samples: this pattern was absent from five fasting and five nonfasting samples in which mucosal squames were the only abnormal finding. All nonfasting control samples exhibited normal geometric ferning. Smears from the cheek and saliva provided the most illustrative findings. The saliva ferning test is a simple, reproducible, and useful diagnostic aid in autoimmune xerostomia, approximately equivalent to Shirmer's test in xerophthalmia.

  17. Transcriptome-mining for single-copy nuclear markers in ferns.

    Directory of Open Access Journals (Sweden)

    Carl J Rothfels

    Full Text Available BACKGROUND: Molecular phylogenetic investigations have revolutionized our understanding of the evolutionary history of ferns-the second-most species-rich major group of vascular plants, and the sister clade to seed plants. The general absence of genomic resources available for this important group of plants, however, has resulted in the strong dependence of these studies on plastid data; nuclear or mitochondrial data have been rarely used. In this study, we utilize transcriptome data to design primers for nuclear markers for use in studies of fern evolutionary biology, and demonstrate the utility of these markers across the largest order of ferns, the Polypodiales. PRINCIPAL FINDINGS: We present 20 novel single-copy nuclear regions, across 10 distinct protein-coding genes: ApPEFP_C, cryptochrome 2, cryptochrome 4, DET1, gapCpSh, IBR3, pgiC, SQD1, TPLATE, and transducin. These loci, individually and in combination, show strong resolving power across the Polypodiales phylogeny, and are readily amplified and sequenced from our genomic DNA test set (from 15 diploid Polypodiales species. For each region, we also present transcriptome alignments of the focal locus and related paralogs-curated broadly across ferns-that will allow researchers to develop their own primer sets for fern taxa outside of the Polypodiales. Analyses of sequence data generated from our genomic DNA test set reveal strong effects of partitioning schemes on support levels and, to a much lesser extent, on topology. A model partitioned by codon position is strongly favored, and analyses of the combined data yield a Polypodiales phylogeny that is well-supported and consistent with earlier studies of this group. CONCLUSIONS: The 20 single-copy regions presented here more than triple the single-copy nuclear regions available for use in ferns. They provide a much-needed opportunity to assess plastid-derived hypotheses of relationships within the ferns, and increase our capacity to

  18. Fern Stomatal Responses to ABA and CO2Depend on Species and Growth Conditions.

    Science.gov (United States)

    Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

    2017-06-01

    Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

  19. PIXE study on absorption of arsenate and arsenite by arsenic hyperaccumulating fern (Pteris vittata)

    International Nuclear Information System (INIS)

    Yamazaki, H.; Ishii, K.; Matsuyama, S.

    2008-01-01

    Pytoremediation using an arsenic hyperaccumulator, Petris vittata L., has generated an increasing interest worldwide due to both environmentally sound and cost effectiveness. However the mechanism of arsenic accumulation by this fern is not clear at this time. This study examined the uptake of arsenate (As(V)) and arsenite (As(III)) by a hydroponic culture of Pteris vittata using both in-air submilli-PIXE for different parts of the fern and in-air micro-PIXE for the tissue cells. These PIXE analysis systems used 3 MeV proton beams from a 4.5-MV single-ended Dynamitron accelerator at Tohoku University, Japan. The fern took up both arsenate and arsenite from hydroponic solutions which were spiked with 50 mg of arsenic per litter. Final amount of arsenic accumulation in the fern is 1,500 mg per kg (wet weight) of the plant biomass in arsenite treatment and 1,100 mg per kg in arsenate treatment. Arsenic accumulation was not observed at the root parts of the ferns. The in-vivo mapping of elements by submilli-PIXE analyses on the fern laminas showed the arsenic accumulation in the edges of a pinna. The micro-PIXE analyses revealed arsenic maps homogeneously distributed in cells of the lamina, stem and rhizome of the fern. These results indicate that arsenic, both arsenate and arsenite in a contaminated medium are translocated quickly from roots to fronds of Pteris vittata, and distributes homogeneously into tissue cells of the fern laminas. (author)

  20. Natural Regeneration after Long-Term Bracken Fern Control with Balsa (Ochroma pyramidale in the Neotropics

    Directory of Open Access Journals (Sweden)

    Samuel I. Levy-Tacher

    2015-06-01

    Full Text Available In many parts of the Neotropics, deforested areas are often colonized by the highly competitive invasive bracken fern (Pteridium aquilinum, which inhabits naturally regenerated forests and successional forests on abandoned farmland. Within the tropical forest region of Chiapas in southern Mexico, we implemented an experiment in 2005 to out-compete bracken fern infestation and reduce or eliminate live bracken rhizomes using several treatments: Direct sowing of balsa seeds (Ochroma pyramidale; Malvaceae, a traditional Lacandon treatment of scattering balsa seeds, transplanting balsa seedlings, and a control treatment (without balsa. For each treatment, we applied three different bracken weeding frequencies: No weeding, biweekly weeding, and monthly weeding. In this study, we present data gathered four years after establishing the experiment regarding: Bracken fern rhizome biomass, balsa density, basal area, height, density, species richness of naturally regenerating vegetation for all treatments, and bracken weeding frequencies. We also evaluated the importance of balsa and its regenerative attributes in controlling bracken fern by correlating it with remaining belowground live rhizome biomass. Living rhizome biomass was completely eradicated in all treatments with biweekly and monthly weeding. Density and species richness of a naturally regenerated species were negatively correlated with bracken fern rhizome biomass, and the density of this species was highest in areas with no rhizome biomass. Although balsa tree stands are effective short-term solutions for controlling rhizome biomass, the success of natural regeneration following balsa establishment can be critical to long-term elimination of bracken fern.

  1. Stable transformation of ferns using spores as targets: Pteris vittata and Ceratopteris thalictroides.

    Science.gov (United States)

    Muthukumar, Balasubramaniam; Joyce, Blake L; Elless, Mark P; Stewart, C Neal

    2013-10-01

    Ferns (Pteridophyta) are very important members of the plant kingdom that lag behind other taxa with regards to our understanding of their genetics, genomics, and molecular biology. We report here, to our knowledge, the first instance of stable transformation of fern with recovery of transgenic sporophytes. Spores of the arsenic hyperaccumulating fern Pteris vittata and tetraploid 'C-fern Express' (Ceratopteris thalictroides) were stably transformed by Agrobacterium tumefaciens with constructs containing the P. vittata actin promoter driving a GUSPlus reporter gene. Reporter gene expression assays were performed on multiple tissues and growth stages of gametophytes and sporophytes. Southern-blot analysis confirmed stable transgene integration in recovered sporophytes and also confirmed that no plasmid from A. tumefaciens was present in the sporophyte tissues. We recovered seven independent transformants of P. vittata and four independent C. thalictroides transgenics. Inheritance analyses using β-glucuronidase (GUS) histochemical staining revealed that the GUS transgene was stably expressed in second generation C. thalictroides sporophytic tissues. In an independent experiment, the gusA gene that was driven by the 2× Cauliflower mosaic virus 35S promoter was bombarded into P. vittata spores using biolistics, in which putatively stable transgenic gametophytes were recovered. Transformation procedures required no tissue culture or selectable marker genes. However, we did attempt to use hygromycin selection, which was ineffective for recovering transgenic ferns. This simple stable transformation method should help facilitate functional genomics studies in ferns.

  2. Glycoside Hydrolase (GH) 45 and 5 Candidate Cellulases in Aphelenchoides besseyi Isolated from Bird?s-Nest Fern

    OpenAIRE

    Wu, Guan-Long; Kuo, Tzu-Hao; Tsay, Tung-Tsuan; Tsai, Isheng J.; Chen, Peichen J.

    2016-01-01

    Five Aphelenchoides besseyi isolates collected from bird's-nest ferns or rice possess different parasitic capacities in bird's-nest fern. Two different glycoside hydrolase (GH) 45 genes were identified in the fern isolates, and only one was found in the rice isolates. A Abe GH5-1 gene containing an SCP-like family domain was found only in the fern isolates. Abe GH5-1 gene has five introns suggesting a eukaryotic origin. A maximum likelihood phylogeny revealed that Abe GH5-1 is part of the nem...

  3. Survival and growth of epiphytic ferns depend on resource sharing

    Directory of Open Access Journals (Sweden)

    Hua-Zheng eLu

    2016-03-01

    Full Text Available Locally available resources can be shared within clonal plant systems through physiological integration, thus enhancing their survival and growth. Most epiphytes exhibit clonal growth habit, but few studies have tested effects of physiological integration (resource sharing on survival and growth of epiphytes and whether such effects vary with species. We conducted two experiments, one on individuals (single ramets and another on groups (several ramets within a plot, with severed and intact rhizome treatments (without and with physiological integration on two dominant epiphytic ferns (Polypodiodes subamoena and Lepisorus scolopendrium in a subtropical montane moist forest in Southwest China. Rhizome severing (preventing integration significantly reduced ramet survival in the individual experiment and number of surviving ramets in the group experiment, and it also decreased biomass of both species in both experiments. However, the magnitude of such integration effects did not vary significantly between the two species. We conclude that resource sharing may be a general strategy for clonal epiphytes to adapt to forest canopies where resources are limited and heterogeneously distributed in space and time.

  4. Phylogenetic Relationships of the Fern Cyrtomium falcatum (Dryopteridaceae from Dokdo Island Based on Chloroplast Genome Sequencing

    Directory of Open Access Journals (Sweden)

    Gurusamy Raman

    2016-12-01

    Full Text Available Cyrtomium falcatum is a popular ornamental fern cultivated worldwide. Native to the Korean Peninsula, Japan, and Dokdo Island in the Sea of Japan, it is the only fern present on Dokdo Island. We isolated and characterized the chloroplast (cp genome of C. falcatum, and compared it with those of closely related species. The genes trnV-GAC and trnV-GAU were found to be present within the cp genome of C. falcatum, whereas trnP-GGG and rpl21 were lacking. Moreover, cp genomes of Cyrtomium devexiscapulae and Adiantum capillus-veneris lack trnP-GGG and rpl21, suggesting these are not conserved among angiosperm cp genomes. The deletion of trnR-UCG, trnR-CCG, and trnSeC in the cp genomes of C. falcatum and other eupolypod ferns indicates these genes are restricted to tree ferns, non-core leptosporangiates, and basal ferns. The C. falcatum cp genome also encoded ndhF and rps7, with GUG start codons that were only conserved in polypod ferns, and it shares two significant inversions with other ferns, including a minor inversion of the trnD-GUC region and an approximate 3 kb inversion of the trnG-trnT region. Phylogenetic analyses showed that Equisetum was found to be a sister clade to Psilotales-Ophioglossales with a 100% bootstrap (BS value. The sister relationship between Pteridaceae and eupolypods was also strongly supported by a 100% BS, but Bayesian molecular clock analyses suggested that C. falcatum diversified in the mid-Paleogene period (45.15 ± 4.93 million years ago and might have moved from Eurasia to Dokdo Island.

  5. Knowledge-Based Estimation of Edible Fern Harvesting Sites in Mountainous Communities of Northeastern Japan

    Directory of Open Access Journals (Sweden)

    Toshiya Matsuura

    2013-12-01

    Full Text Available Once local expert knowledge regarding the harvesting of various non-timber forest products (NTFPs is lost, it is difficult to recover. We investigated whether the knowledge of expert forest harvesters can be used to determine the habitat distribution and harvesting sites of three popular edible wild ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous communities of western Fukushima, Japan. Using multi-criteria evaluation (MCE based on the analytic hierarchy process (AHP and geographic information system (GIS, we found that harvesters were easily able to recognize differences in the spatial characteristics of the habitat distribution of fern species due to both natural and anthropogenic factors. These factors were described by various GIS layers, such as vegetation and terrain features (e.g., gradient, aspect, and slope position derived from a 20-m digital elevation model (DEM. Harvesting sites were limited by their distance from a roadway, which differed among species. By comparison with the GPS records of actual harvesting sites, we estimated the potential harvesting sites of each fern species with reasonable accuracy, particularly for bracken. Our results show that the knowledge of expert forest harvesters can be quantified using MCE and GIS, which is useful for determining the spatial characteristics of NTFP harvesting and ensuring sustainable management practices.

  6. Edge effects on fern community in an Atlantic Forest remnant of Rio Formoso, PE, Brazil.

    Science.gov (United States)

    Silva, I A A; Pereira, A F N; Barros, I C L

    2011-05-01

    We have investigated how edge effects influence the fern community of Jaguarão Forest (08º 35' 49" S and 35º 15' 39" W), located in the district of Rio Formoso, Pernambuco, Brazil. A comparative analysis was made of the interior and edge of the fragment of forest, regarding the richness, abundance and diversity of ferns in the two areas. Six plots of 10 × 20 m were chosen, three in each area. A total of 381 ferns were recorded, which were distributed among 25 species, 17 genera and 12 families. The two areas (edge and interior) were found to differ, with distinct relative air humidities and temperatures (p = 0.00254 and p = 0.00019, respectively). The interior showed higher diversity (t = 7.251 and p = 0.018) and richness (t = 6.379 and p = 0.023) than the edge area, but the same abundance (t = 1.728; p = 0.226) as the edge. Regarding the composition of the flora, it was clear that the interior is a habitat completely distinct from the edge with regard to the fern community, given that only one species, Adiantum petiolatum Desv., was common to both environments. It was concluded that the edge effect causes a decrease in richness and abundance of the fern species found in Jaguarão Forest, where the more sensitive species are being replaced by species that are tolerant to the disturbance caused by the creation of an edge.

  7. Restoring Native Forest Understory: The Influence of Ferns and Light in a Hawaiian Experiment

    Directory of Open Access Journals (Sweden)

    Robert Shallenberger

    2013-03-01

    Full Text Available Ecological restoration is an increasingly important component of sustainable land management. We explore potential facilitative relationships for enhancing the cost-effectiveness of restoring native forest understory, focusing on two factors: (1 overstory shade and (2 possible facilitation by a fern (Dryopteris wallichiana, one of few native colonists of pasture in our montane Hawaiˈi study system. We planted 720 understory tree seedlings and over 4000 seeds of six species under six planting treatments: a full factorial combination of low, medium and high light, situating plantings in either the presence or absence of a mature fern. After three years, 75% of outplanted seedlings survived. Seedling survivorship was significantly higher in the presence of a fern (79% vs. 71% without a fern and in medium and low light conditions (81% vs. 64% in high light. Relative height was highest at low to medium light levels. After 2.2 years, 2.8% of the planted seeds germinated. We observed no significant differences in seed germination relative to light level or fern presence. Analyzing several approaches, we found nursery germination of seeds followed by outplanting ca. 20% less costly than direct seeding in the field. This study opens new questions about facilitation mechanisms that have the potential to increase the extent and effectiveness of restoration efforts.

  8. Miocene fern spores and pollen grains from the Solimões Basin, Amazon Region, Brazil

    Directory of Open Access Journals (Sweden)

    Natália de Paula Sá

    Full Text Available ABSTRACT This work documents fern spores and pollen grains (miospores recovered from rocks of the Solimões Formation (Solimões Basin, their botanical affinities, ecology and distribution in the Miocene of the Amazon Region. The assemblage of miospores is well preserved and diverse. They are identified, illustrated and assigned to the ten families of ferns and 22 families of spermatophytes. All miospores were identified to the taxonomic level of species except for two taxa (Perinomonoletes and Podocarpidites. The families Pteridaceae and Arecaceae were most representative of ferns and spermatophytes, respectively. This work contributes to the knowledge of the paleoflora and will aid in paleoenvironmental, paleoecological and biostratigraphic interpretations of the Miocene of the Amazon Region.

  9. Identifying potential habitat for the endangered Aleutian shield fern using topographical characteristics

    Science.gov (United States)

    Duarte, Adam; Wolcott, Daniel M.; Chow, T. Edwin

    2012-01-01

    The Aleutian shield fern Polystichum aleuticum is endemic to the Aleutian archipelago of Alaska and is listed as endangered pursuant to the U.S. Endangered Species Act. Despite numerous efforts to discover new populations of this species, only four known populations are documented to date, and information is needed to prioritize locations for future surveys. Therefore, we incorporated topographical habitat characteristics (elevation, slope, aspect, distance from coastline, and anthropogenic footprint) found at known Aleutian shield fern locations into a Geographical Information System (GIS) model to create a habitat suitability map for the entirety of the Andreaonof Islands. A total of 18 islands contained 489.26 km2 of highly suitable and moderately suitable habitat when weighting each factor equally. This study reports a habitat suitability map for the endangered Aleutian shield fern using topographical characteristics, which can be used to assist current and future recovery efforts for the species.

  10. Abiotic factors drives floristic variations of fern's metacommunity in an Atlantic Forest remnant.

    Science.gov (United States)

    Costa, L E N; Farias, R P; Santiago, A C P; Silva, I A A; Barros, I C L

    2018-02-15

    We analyzed floristic variations in fern's metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern's flora showed high floristic heterogeneity (>75% for most of the plot's associations). The fern's metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

  11. Purification and amino acid sequence of a fern (Gleichenia japonica) ferredoxin.

    Science.gov (United States)

    Hase, T; Yamanashi, H; Matsubara, H

    1982-01-01

    A chloroplast-type ferredoxin was purified from a fern, Gleichenia japonica, and its amino acid sequence was determined. The conventional method for soft leaves proved to be unsuitable for the extraction of ferredoxin from G. japonica, but a good yield was obtained by blending the leaves in cold acetone. The analysis of 8 tryptic peptides of Cm-ferredoxin gave the complete amino acid sequence. The molecule consisted of a single polypeptide chain of 95 amino acid sequence. The molecule consisted of a single polypeptide chain of 95 amino acid residues and lacked tryptophan. Relatively high contents of phenylalanine and arginine were noted, some of which had unique locations in comparison with other ferredoxins. G. japonica ferredoxin did not show a close sequence homology with the ferredoxins from horsetails, which, like ferns, belong to Pteridophyta, or with those from plants of different taxonomical groups. The fern ferredoxins were suggested to form a unique group in the chloroplast-type ferredoxins.

  12. The first fossil of a bolbitidoid fern belongs to the early-divergent lineages of Elaphoglossum (Dryopteridaceae).

    Science.gov (United States)

    Lóriga, Josmaily; Schmidt, Alexander R; Moran, Robbin C; Feldberg, Kathrin; Schneider, Harald; Heinrichs, Jochen

    2014-09-01

    • Closing gaps in the fossil record and elucidating phylogenetic relationships of mostly incomplete fossils are major challenges in the reconstruction of the diversification of fern lineages through time. The cosmopolitan family Dryopteridaceae represents one of the most species-rich families of leptosporangiate ferns, yet its fossil record is sparse and poorly understood. Here, we describe a fern inclusion in Miocene Dominican amber and investigate its relationships to extant Dryopteridaceae.• The morphology of the fossil was compared with descriptions of extant ferns, resulting in it being tentatively assigned to the bolbitidoid fern genus Elaphoglossum. This assignment was confirmed by reconstructing the evolution of the morphological characters preserved in the inclusion on a molecular phylogeny of 158 extant bolbitidoid ferns. To assess the morphology-based assignment of the fossil to Elaphoglossum, we examined DNA-calibrated divergence time estimates against the age of the amber deposits from which it came.• The fossil belongs to Elaphoglossum and is the first of a bolbitidoid fern. Its assignment to a particular section of Elaphoglossum could not be determined; however, sects. Lepidoglossa, Polytrichia, and Setosa can be discounted because the fossil lacks subulate scales or scales with acicular marginal hairs. Thus, the fossil might belong to either sects. Amygdalifolia, Wrightiana, Elaphoglossum, or Squamipedia or to an extinct lineage.• The discovery of a Miocene Elaphoglossum fossil provides remarkable support to current molecular clock-based estimates of the diversification of these ferns. © 2014 Botanical Society of America, Inc.

  13. Use of rbcL and trnL-F as a two-locus DNA barcode for identification of NW-European ferns: an ecological perspective

    NARCIS (Netherlands)

    Groot, de G.A.; During, H.J.; Maas, J.W.; Schneider, H.; Erkens, R.H.J.

    2011-01-01

    Although consensus has now been reached on a general two-locus DNA barcode for land plants, the selected combination of markers (rbcL + matK) is not applicable for ferns at the moment. Yet especially for ferns, DNA barcoding is potentially of great value since fern gametophytes—while playing an

  14. An Early Cretaceous root-climbing epiphyte (Lindsaeaceae) and its significance for calibrating the diversification of polypodiaceous ferns.

    Science.gov (United States)

    Schneider, H; Kenrick, P

    2001-05-01

    The discovery of fossilised roots of a lindsaeoid fern within the trunk of the extinct tree fern Tempskya provides new fossil evidence for Lindsaeaceae in the Mesozic, as well as the first direct evidence of an ecological association between Tempskya and root-climbing epiphytes. Data were collected from permineralised Tempskya trunks from the Aspen Shale (Early Cretaceous, Albian), Wyoming (USA). The roots of the lindsaeoid fossil are clearly distinguishable from those of Tempskya and other living ferns based on a suite of distinctive anatomical features, which are described in detail. The foliage is unknown. The new fossil is interpreted as a root climber, and comparisons are made with similar living species in Lindsaea subgenus Odontoloma (Lindsaeaceae). The documentation of Lindsaeaceae in the Early Cretaceous adds to a small but growing body of data on the diversification of polypodiaceous ferns during this important period. These recent discoveries point to a much earlier (Early Cretaceous) crown group radiation of polypodiaceous ferns than previously suspected.

  15. Determination of heavy metals in soil and different parts of Diplazium esculentum (medicinal fern)

    Science.gov (United States)

    Jasim, Hind S.; Idris, Mushrifah; Abdullah, Aminah; Kadhum, A. A. H.

    2014-09-01

    Diplazium esculentum is a widely used medicinal fern in Malaysia and other regions worldwide. Heavy metals in plants should be determined because prolonged human intake of toxic trace elements, even at low doses, results in organ malfunction and causes chronic toxicity. Hence, substantial information should be obtained from plants that grow on soils containing high concentrations of heavy metals. This study aimed to determine the physicochemical characteristics of soil and heavy metal concentrations (Pb, Cr, Mn, Cu, and Zn) in different parts of D. esculentum and soil, which were collected from the fern garden of Universiti Kebangsaan Malaysia. Results showed that heavy metals were highly accumulated in D. esculentum roots.

  16. Fern extracts potentiate fluconazole activity and inhibit morphological changes in Candida species

    Directory of Open Access Journals (Sweden)

    Maria A. Freitas

    2017-11-01

    Conclusions: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.

  17. Exploring Form and Pattern: Pinecone, Fern, and Tafoni

    Science.gov (United States)

    Boxerman, J.; Kudritzki, P.; Tanner, K.

    2005-12-01

    During the 2004-20005 school year, two classes of sixth-grade earth scientists from Aptos Middle School in San Francisco explored forms and patterns of various natural objects. This classroom was unique in that there was a partner geoscientist working with the teacher and students several days a week throughout the school year as part of the SFSU GK-12 Partnership Program. This lesson on form and pattern was inspired by the challenge to create a hands-on investigative activity about forms and patterns in Nature that could compliment the partner geoscientist's Masters research project on the tafoni rock weathering pattern. In this fun, engaging, and distinct hands-on earth science activity, students actively investigated forms and patterns using tools such as rulers and hand lenses. The lesson objectives were to teach students about form and pattern and to help students recognize forms and patterns through careful investigation of natural objects. The natural objects were pre-selected for their well-defined forms and patterns and included: a pinecone, a fern branch, a foliated sandstone, a pineapple, a succulent limb, a cross-section from a redwood tree, a spiraling shell, and a section of sandstone undergoing tafoni weathering. To assess student learning, students were asked to define both form and pattern before and after the activity. A positive shift in student responses occurred, and students learned how to identify a form and interpret how a form can repeat spatially to create a pattern. Sketches and observation notes students made demonstrate that they had become more sophisticated observers of forms and patterns in natural objects. This activity was very successful and all students actively participated. Fruitful class discussions suggested that most students were well prepared by this activity to understand the essence of the partner geoscientist's research on tafoni. Emphasizing form and pattern to explain a complex and esoteric geologic phenomenon made

  18. FURTHER NOTES ON THE FERN-GENUS HETEROGONIUM PRESL

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    R. E. HOLTTUM

    2015-11-01

    Full Text Available In the "Sarawak Museum Journal," volume V (1949, pages 156-166,I gave a revised account of the genus Heterogonium Presl, based on specimens in the Singapore herbarium. Dr M. A. Donk wrote subsequently pointing out that specimens at Bogor (Buitenzorg add materially to the information contained in that paper. The present paper gives the result of a study of the Bogor specimens. I am glad to express my gratitude to Dr Donk for calling my attention to species which I had overlooked when searching literature on Malaysian ferns for indications of affinity to Heterogonium. The Bogor material includes the type specimens of Acrostichum teysmannianum Bak., Phegopteris schizoloma v. A. v. R. Dryopteris sagenoides forma contracta v. A. v. R., Polybotrya nieuwenhuisii Racib. and Polybotrya nieuwenhuisii var. brooksii v. A. v. R., also many sheets of H. giganteum, and material of H. sagenoides from a wider geographic range than I had previously seen. Summarizing the results of the present paper, I have united H.nieuwenhuisii and H. stenosemioides of my former paper, and have also united H. saxicola with H. giganteum. Further, I now recognize a second exindusiate species allied to H. sagenoides; but the variation in pubescence among exindusiate specimens, as within the species H. sagenoides proper, is very considerable, and I find it very difficult to draw specific limits. It is likely that there are local races, but much more field work in many localities is necessary before one can speak with certainty about this or define their status taxonomically. One interesting fact is that no exindusiate specimens of this alliance have been found in the Malay Peninsula, whereas Peninsular collections of indusiate H. sagenoides aremore abundant than from any other area. It is especially the variation in pubescence among specimens of H. sagenoides, and the lack of clear-cut varieties or subspecies within the Malay Peninsula, that deters me from distinguishing more

  19. Evolution of Inbreeding and Outcrossing in Ferns and Fern-Allies(US-JAPAN SEMINAR : EVOLUTIONARY STUDIES ON SEXUAL SYSTEMS IN PLANTS)

    OpenAIRE

    PAMELA S., SOLTIS; DOUGLAS E., SOLTIS; Department of Botany, Washington State University; Department of Botany, Washington State University

    1990-01-01

    Mating systems of 18 species of homosporous ferns follow a bimodal distribution, similar to that observed for seed plants (Schemske and Lande, 1985). Most species are highly outcrossing, a few are inbreeding, and two species examined to date have mixed mating systems. Equisetum arvense and several species of lycopods are also highly outcrossing. Several mechanisms, including inbreeding depression, antheridiogen, and ontogenetic sequences that result in effectively unisexual gametophytes, prom...

  20. A biological hazard of our age: bracken fern [Pteridium aquilinum (L.) Kuhn]--a review.

    Science.gov (United States)

    Vetter, János

    2009-03-01

    Bracken fern (Pteridium aquilinum) is the fifth most distributed common weed species of the world. Its ecological distribution is very wide, and the plant can grow and spread successfully on many types of soil. The cover of P. aquilinum is--in some cases--remarkable (e.g., in the United Kingdom). Bracken fern contains different poisonous agents: some cyanogen glycosides, factors (agents) of antithiamine character (thermolabile thiaminase and thermostable other compounds) and factors of carcinogenic activity (first of all ptaquiloside). This paper summarises and reviews different toxicological problems and poisonings caused by bracken fern in ruminants (cattle, sheep) and in non-ruminant animals (horses, pigs, rats, mice, etc.). The carcinogenic properties of the norsesquiterpene-type ptaquiloside make bracken fern a potent, living hazard. Recent investigations have shown that ptaquiloside pollution of different soil layers is a distinct possibility. Ptaquiloside may leach from the soil into the drinking water base. This ecotoxicological aspect seems to be the most hazardous phenomenon in relation to P. aquilinum and ptaquiloside. The carcinogenic effect of ptaquiloside is based on its hydrolysis, which leads to the formation of a dienon intermediate. It can produce DNA adducts, which are responsible for inducing carcinoma.

  1. A review of the fern genus Hypolepis (Dennstardtiaceae) in the Malesian and Pacific regions

    NARCIS (Netherlands)

    Brownsey, P.J.

    1987-01-01

    Fourteen species and one subspecies of the fern genus Hypolepis Bernh. are recognised in the Malesian and Pacific regions, excluding Australia and New Zealand. Three species, H. hawaiiensis, H. malesiana and H. scabristipes, and one subspecies, H. elegans subsp. carolinensis, are described for the

  2. Novel fungi from an ancient niche: lachnoid and chalara-like fungi on ferns

    NARCIS (Netherlands)

    Guatimosim, E.; Schwartsburd, P. B.; Crous, P. W.; Barreto, R. W.

    2016-01-01

    A survey was conducted in Brazil to collect fungi on ferns. Based on morphology and inferred phylogeny from DNA sequences of two loci, namely the internal transcribed spacer (ITS) regions and the large subunit nuclear ribosomal RNA gene (LSU), several species belonging to chalara-like genera and

  3. Community structure of ferns in riparian forest: evaluation in anthropization gradient

    Directory of Open Access Journals (Sweden)

    Ivanete Teresinha Mallmann

    2016-03-01

    Full Text Available Riparian forests are essential to the maintenance of biodiversity and foster the development of ferns that are indicators of environmental quality. However, these forests have been degraded due mainly to high population density, pattern of urban settlement and agricultural expansion in rural areas. This study evaluated the environmental quality of riparian vegetation of the Cadeia River in Southern Brazil, using phytosociological parameters of the understory’s fern community and a Rapid Assessment Protocol of Habitat Quality (RAPQH. One hundred and twenty plots of 25 m2 were equally distributed among three fragments (FI, FII, FIII. All species of herbaceous ferns were inventoried in each sample unit. We calculated parameters of density, frequency, relative dominance and importance value (IV of species for the analysis of community structure. The lowest species richness was recorded at FIII (seven species. The floristic composition is more heterogeneous and richness is higher in FI, where the parcels had greater plant cover and RAPQH scores. The RAPQH score decreased with increasing degree of urbanization in the surrounding matrix and FI and FII were classified as “natural,” while FIII was classified as “impacted.” Considering the four species with the highest IV in the three fragments (totaling 69.11% of IV in the FI, 78.36% and 91.06% in FII and FIII respectively, it can be affirmed that the fern community structure is degraded with increasing anthropization.

  4. The invention of WUS-like stem cell-promoting functions in plants predates leptosporangiate ferns.

    Science.gov (United States)

    Nardmann, Judith; Werr, Wolfgang

    2012-01-01

    The growth of land plants depends on stem cell-containing meristems which show major differences in their architecture from basal to higher plant species. In Arabidopsis, the stem cell niches in the shoot and root meristems are promoted by WUSCHEL (WUS) and WOX5, respectively. Both genes are members of a non-ancestral clade of the WUS-related homeobox (WOX) gene family, which is absent in extant bryophytes and lycophytes. Our analyses of five fern species suggest that a single WUS orthologue was present in the last common ancestor (LCA) of leptosporangiate ferns and seed plants. In the extant fern Ceratopteris richardii, the WUS pro-orthologue marks the pluripotent cell fate of immediate descendants of the root apical initial, so-called merophytes, which undergo a series of stereotypic cell divisions and give rise to all cell types of the root except the root cap. The invention of a WUS-like function within the WOX gene family in an ancestor of leptosporangiate ferns and seed plants and its amplification and sub-functionalisation to different stem cell niches might relate to the success of seed plants, especially angiosperms.

  5. Population biology of two rare fern species: long-life and long-lasting stability

    Czech Academy of Sciences Publication Activity Database

    Bucharová, Anna; Münzbergová, Z.; Tájek, P.

    2010-01-01

    Roč. 97, č. 8 (2010), s. 1260-1271 ISSN 0002-9122 R&D Projects: GA MŽP SP/2D4/112/08 Institutional research plan: CEZ:AV0Z60050516 Keywords : ferns * life cycle * naturally rare species Subject RIV: EF - Botanics Impact factor: 3.052, year: 2010

  6. Cyathea nilgirensis Holttum (Cyatheaceae: Pteridophyta: a threatened tree fern from central Western Ghats, India

    Directory of Open Access Journals (Sweden)

    S.N. Dudani

    2014-01-01

    Full Text Available While studying some of the exclusive and threatened swamps overgrown with wild nutmeg trees (Myristica swamps, in the Kathalekan forest of Uttara Kannada in central Western Ghats, Cyathea nilgirensis Holttum, a southern Indian endemic tree fern was seen growing in the deep shade of the swampy forest. This is a new report of its distribution anywhere from north of Western Ghats.

  7. The Lindsaeoid ferns of the Old World V. The smaller Pacific islands

    NARCIS (Netherlands)

    Kramer, K.U.

    1970-01-01

    The present paper is the third regional revision of the Old World Lindsaeoid ferns. The second (the fourth in the entire series on the Old World Lindsaeoids) will be published as vol. II, 1 part 3 of Flora Malesiana; it is awaiting publication as the present paper goes to the press. Species fully

  8. Western sword fern avoids the extreme drought of 2012-2014

    Science.gov (United States)

    Emily E. Burns; Peter Cowan; Wendy Baxter; Deborah Zierten; Jarmilla Pittermann

    2017-01-01

    The California drought of 2012 to 2014 was the most severe drought on record for the last century and likely millennium. Warm temperatures with below-average precipitation compounded over the three-year period, creating significant and sustained aridity over the course of three growing seasons throughout the coast redwood ecosystem. The citizen science project, Fern...

  9. Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis.

    Directory of Open Access Journals (Sweden)

    David P Blair

    Full Text Available Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 - 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall. Overall, Cyathea australis averaged 73 (± 22mm/year of growth (± 1SD, with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire.

  10. Effects of bracken fern (Pteridium aquilinum L Kuhn) feeding during the development of female rats and their offspring.

    Science.gov (United States)

    Gerenutti, M; Spinosa, H de S; Bernardi, M M

    1992-08-01

    Bracken fern (Pteridium aquilinum L Kuhn), is widely food in many parts of the world; the toxic effects have been demonstrated on many species of animals, and both carcinogenicity and enzootic hematuria has been studied. We investigated the effects of feeding bracken fern on the development of female rats and their offspring. The plant was fed as 30% of the normal diet on an ad libitum basis. Bracken fern did not modify the weight gain of the female rats during development, nor affect estrus cycle duration or milk production, the plant did reduce female fertility and weight gain during pregnancy. It also adversely affected physical and neurobehavioral development in the offspring.

  11. Mycorrhizal association in gametophytes and sporophytes of the fern Pteris vittata (Pteridaceae with Glomus intraradices

    Directory of Open Access Journals (Sweden)

    Alicia E Martinez

    2012-06-01

    Full Text Available Ferns, which are usually colonizing different environments and their roots frequently present mycorrhization, have two adult stages in their life cycle, the sporophytic and the gametophytic phase. This paper describes the experimental mycorrhizal association between Pteris vittata leptosporangiate fern and a strain of Glomus intraradices during the life cycle of the fern, from spore germination to the development of a mature sporophyte. The aim of this study was to compare the colonization pattern of in vitro cultures of G. intraradices along the fern life cycle with those found in nature. For this, mature spores were obtained from fertile P. vittata fronds growing in walls of Buenos Aires city, Argentina. Roots were stained and observed under the light microscope for arbuscular mycorrhizal colonization. Approximately, 75 fern spores were cultured in each pot filled with a sterile substrate and G. intraradices (BAFC N° 51.331 as inoculum on the surface. After germination took place, samples were taken every 15 days until the fern cycle was completed. In order to determine colonization dynamics each sample was observed under optical and confocal microscope after staining. Gametophyte was classified as Adiantum type. Male and female gametangia were limited to the lower face, mycorrhizal colonization started when they were differentiated and took place through the rhizoids. Spores and vesicles were not found in this cycle stage. Paris-type mycorrhizal colonization was established in the midrib and in the embrionary foot. It was colonized by external mycelium. When the first root was developed soil inoculum colonized de novo this structure and Arum-type colonization was observed. This study proves that the type of colonization is determined by the structure of the host, not by the fungus. Both the gametophyte and embryo foot have determined growth and Paris-type colonization, while, sporophyte roots have undetermined growth and Arum

  12. Isolation of polymorphic microsatellite markers and tests of cross-amplification in four widespread European calcicole ferns

    NARCIS (Netherlands)

    Groot, de G.A.; Korpelainen, H.; Wubs, E.R.J.; Erkens, R.H.J.

    2011-01-01

    Premise of the study: Studies on the biogeography and population genetics of the widespread European rock ferns Asplenium scolopendrium , A. trichomanes subsp. quadrivalens , Polystichum setiferum , and P. aculeatum would potentially yield interesting new insights into the colonization capacities of

  13. Ferns are less dependent on passive dilution by cell expansion to coordinate leaf vein and stomatal spacing than angiosperms.

    Directory of Open Access Journals (Sweden)

    Madeline R Carins Murphy

    Full Text Available Producing leaves with closely spaced veins is a key innovation linked to high rates of photosynthesis in angiosperms. A close geometric link between veins and stomata in angiosperms ensures that investment in enhanced venous water transport provides the strongest net carbon return to the plant. This link is underpinned by "passive dilution" via expansion of surrounding cells. However, it is not known whether this 'passive dilution' mechanism is present in plant lineages other than angiosperms and is another key feature of the angiosperms' evolutionary success. Consequently, we sought to determine whether the 'passive dilution' mechanism is; (i exclusive to the angiosperms, (ii a conserved mechanism that evolved in the common ancestor of ferns and angiosperms, or (iii has evolved continuously over time. To do this we first we assessed the plasticity of vein and stomatal density and epidermal cell size in ferns in response to light environment. We then compared the relationships between these traits found among ferns with modelled relationships that assume vein and stomatal density respond passively to epidermal cell expansion, and with those previously observed in angiosperms. Vein density, stomatal density and epidermal cell size were linked in ferns with remarkably similar relationships to those observed in angiosperms, except that fern leaves had fewer veins per stomata. However, plasticity was limited in ferns and stomatal spacing was dependent on active stomatal differentiation as well as passive cell expansion. Thus, ferns (like angiosperms appear to coordinate vein and stomatal density with epidermal cell expansion to some extent to maintain a constant ratio between veins and stomata in the leaf. The different general relationships between vein density and stomatal density in ferns and angiosperms suggests the groups have different optimum balances between the production of vein tissue dedicated to water supply and stomatal tissue for gas

  14. Interaction of bracken-fern extract with vitamin C in human submandibular gland and oral epithelium cell lines.

    Science.gov (United States)

    Campos-da-Paz, Mariana; Pereira, Luciana O; Bicalho, Leandro Santos; Dórea, José G; Poças-Fonseca, Marcio J; Santos, Maria de Fátima M Almeida

    2008-04-30

    The consumption of bracken-fern (Pteridium aquilinum) as food is associated with a high incidence of cancer in humans and animals. Thus far, the carcinogenic effects of bracken-fern consumption could be related to chromosome aberrations verified in animal and in human peripheral lymphocytes. We tested the in vitro effects of vitamin C (10 and 100 microg/ml) on the reversibility of DNA damage caused by bracken-fern on human submandibular gland (HSG) cells and on oral epithelium cells (OSCC-3) previously exposed to bracken-fern extract. DNA damage (i.e. nuclei with increased levels of DNA migration) was determined by comet assay, cell morphology was evaluated by light microscopy and cellular degeneration was assessed by the acridine orange/ethidium bromide fluorescent-dyeing test. Results showed that vitamin C alone did not reduce DNA damage caused by bracken-fern in HSG and OSSC-3 cells. However, at a higher concentration (100 microg/ml), vitamin C induced DNA damage in both cell lines. Moreover, vitamin C (10 and 100 microg/ml) together with bracken-fern extract showed synergistic effects on the frequency of DNA damage in HSG cells. In addition, cells treated with bracken-fern extract or vitamin C alone, or with their association, showed apoptosis morphological features, such as chromatin condensation, cytoplasmic volume loss, changes in membrane symmetry and the appearance of vacuoles; these alterations were observed in both cell lines. These results demonstrate that bracken-fern extract was cytotoxic to HSG and OSCC-3 cells, causing cell death by apoptosis, and that vitamin was not able to revert these effects.

  15. No evidence of general CO2 insensitivity in ferns: one stomatal control mechanism for all land plants?

    Science.gov (United States)

    Franks, Peter J; Britton-Harper, Zoe J

    2016-08-01

    Stomatal regulation of plant carbon uptake and water loss under changing environmental conditions was a crucial evolutionary step in the colonization of land by plants. There are currently two conflicting models describing the nature of stomatal regulation across terrestrial vascular plants: the first is characterized by a fundamental mechanistic similarity across all lineages, and the second is characterized by the evolution of major differences in angiosperms compared with more ancient lineages. Specifically, the second model posits that stomata of ferns lack a response to elevated atmospheric CO2 concentration (ca ) and therefore cannot regulate leaf intercellular CO2 concentration (ci ). We compared stomatal sensitivity to changes in ca in three distantly related fern species and a representative angiosperm species. Fern and angiosperm stomata responded strongly and similarly to changes in ca . As a result, ci /ca was maintained within narrow limits during ca changes. Our results challenge the model in which stomata of ferns generally lack a response to elevated ca and that angiosperms evolved new dynamic mechanisms for regulating leaf gas exchange that differ fundamentally from ferns. Instead, the results are consistent with a universal stomatal control mechanism that is fundamentally conserved across ferns and angiosperms, and therefore likely all vascular plant divisions. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  16. Stable Transformation of Ferns Using Spores as Targets: Pteris vittata and Ceratopteris thalictroides1[W][OPEN

    Science.gov (United States)

    Muthukumar, Balasubramaniam; Joyce, Blake L.; Elless, Mark P.; Stewart, C. Neal

    2013-01-01

    Ferns (Pteridophyta) are very important members of the plant kingdom that lag behind other taxa with regards to our understanding of their genetics, genomics, and molecular biology. We report here, to our knowledge, the first instance of stable transformation of fern with recovery of transgenic sporophytes. Spores of the arsenic hyperaccumulating fern Pteris vittata and tetraploid ‘C-fern Express’ (Ceratopteris thalictroides) were stably transformed by Agrobacterium tumefaciens with constructs containing the P. vittata actin promoter driving a GUSPlus reporter gene. Reporter gene expression assays were performed on multiple tissues and growth stages of gametophytes and sporophytes. Southern-blot analysis confirmed stable transgene integration in recovered sporophytes and also confirmed that no plasmid from A. tumefaciens was present in the sporophyte tissues. We recovered seven independent transformants of P. vittata and four independent C. thalictroides transgenics. Inheritance analyses using β-glucuronidase (GUS) histochemical staining revealed that the GUS transgene was stably expressed in second generation C. thalictroides sporophytic tissues. In an independent experiment, the gusA gene that was driven by the 2× Cauliflower mosaic virus 35S promoter was bombarded into P. vittata spores using biolistics, in which putatively stable transgenic gametophytes were recovered. Transformation procedures required no tissue culture or selectable marker genes. However, we did attempt to use hygromycin selection, which was ineffective for recovering transgenic ferns. This simple stable transformation method should help facilitate functional genomics studies in ferns. PMID:23933990

  17. Nona Fernández's Mapocho: Spirits in a Material Wasteland

    Directory of Open Access Journals (Sweden)

    Resha S Cardone

    2015-01-01

    Full Text Available This analysis of Mapocho (2002, a novel by Chilean writer and performer Nona Fernández, explores the significance of the author’s environmentalist representation of Chilean history as the accumulation of spiritual and material contaminants—ghosts and trash—that the victorious from throughout the country’s history have attempted to erase to further various economic and political agendas, particularly the neoliberal model installed during the Pinochet dictatorship. Fernández’s depiction of Chile as an ecological and spiritual wasteland in which the female protagonist (recollects, recycles and reuses the specters and detritus of past conflicts represents the author’s own literary project of advocating for human rights and environmental justice during the Chilean transition while modeling a way to counter the collective amnesia promoted under the newly established democracy.

  18. Multiple effects of bracken fern under in vivo and in vitro conditions.

    Science.gov (United States)

    Tourchi-Roudsari, Motahhareh

    2014-01-01

    Several toxic substances have been detected in plants which are responsible for animal and human diseases. Bracken fern (Pteridium aquilinum) is one example, widely distributed in many parts of the world. It is known to cause cancer in humans and other animals. In fact, man can be directly or indirectly exposed to the danger by consuming fern, contaminated water, milk, meat, and spore inhalation. Experimental studies have shown an association between bracken exposure and gastric cancer, and research has shown genotoxic and cytotoxic effects in vitro. This paper describes and reviews toxic, carcinogenic, genotoxic/cytotoxic, and immunomodulatory effects of bracken and included possible toxic agents. The chemistry of Ptaquiloside (PT) reactions is emphasized, along with bracken problems in livestock, possible pathways of exposure in man, and control for human health.

  19. Microstructural changes in rabbit meat wrapped with Pteridium aquilinum fern during postmortem storage.

    Science.gov (United States)

    Sotelo, I; Pérez-Munuera, I; Quiles, A; Hernando, I; Larrea, V; Lluch, M A

    2004-04-01

    This work studied the microstructural degradation of rabbit semimembranosus muscle wrapped with Pteridium aquilinum fern fronds, stored at 4 °C during the first 72 h postmortem. At the microstructural level, practically all the perimysial and endomysial connective tissue was destroyed and a small degradation of the myofibrils could be observed after the first 24 h postmortem; in addition, a degradation of the sarcolemma and the generation of numerous gaps were seen. After 32 h postmortem, tissue fibres were broken, cell membranes were more strongly degraded, and the connections between the sarcolemma and the myofibrils had disappeared. After 72 h postmortem, intercellular connections became degraded inside the muscle bundles and intercellular gaps became larger. The proteolytic activity is attributed to fern endogenous enzymatic activity in addition to the typical endogenous enzymatic activity of meat postmortem.

  20. Induction of tumors in rats by bracken fern (Pteridium aquilinum) from Ouro Preto (Minas Gerais, Brazil).

    Science.gov (United States)

    Santos, R C; Brasileiro-Filho, G; Hojo, E S

    1987-01-01

    1. The possible carcinogenicity of bracken fern (Pteridium aquilinum, common name: "Broto de Samambaia") which is used as food by the population of Ouro Preto (Minas Gerais, Brazil) and neighboring areas, was studied in rats. 2. Fifteen (6 female and 9 male) 45-day old Wistar rats were fed a diet containing dried bracken fern (5%, w/w) for up to 70 weeks. After death or sacrifice, the animals were carefully examined for tumors in the gastrointestinal tract, bladder, lungs, liver, and kidneys. 3. All experimental animals showed gastrointestinal tract tumors which were located mainly in the ileum. Most of the tumors were malignant lesions (adenocarcinomas and sarcomas), although benign adenomas were also present. One animal developed a lymphoma and none showed vesical tumors. 4. No tumors were detected in 11 control rats (5 female and 6 male). 5. These data clearly demonstrate that Pteridium aquilinum is carcinogenic for rats.

  1. Libros y lecturas portuguesas del obispo poblano Manuel Fernández de Santa Cruz

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    Pedro RUEDA

    2018-01-01

    Full Text Available Resumen Se analizará una lista de libros portugueses adquiridos en Lisboa y remitidos desde Cádiz a Manuel Fernández de Santa Cruz, obispo de Puebla de los Ángeles. Los textos que se incluyeron eran obras religiosas, especialmente de teología, sermonarios y devoción; textos de historia portuguesa y de sus colonias, y algunas obras de humanidades y literatura, con un especial interés por los escritos de Francisco Manuel de Melo. Además del análisis de las temáticas se ofrecerán pistas sobre el envío de libros a Manuel Fernández de Santa Cruz desde Cádiz a Puebla en 1683 y ser transcribe la memoria identificado los libros.

  2. Effect of pH on lead removal from water using tree fern as the sorbent.

    Science.gov (United States)

    Ho, Yuh-Shan

    2005-07-01

    The sorption of lead from water onto an agricultural by-product, tree fern, was examined as a function of pH. The sorption processes were carried out using an agitated and baffled system. Pseudo-second-order kinetic analyses were performed to determine the rate constant of sorption, the equilibrium sorption capacity, and the initial sorption rate. Application of the pseudo-second-order kinetics model produced very high coefficients of determination. Results showed the efficiency of tree fern as a sorbent for lead. The optimum pH for lead removal was between 4 and 7, with pH 4.9 resulting in better lead removal. Ion exchange occurred in the initial reaction period. In addition, a relation between the change in the solution hydrogen ion concentration and equilibrium capacity was developed and is presented.

  3. Don Andrés Bello y don José Fernández Madrid

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    Gabriel Giraldo Jaramillo

    1959-05-01

    Full Text Available Breve pero intensa fue la amistad de estos dos ilustres grancolombianos durante su residencia en Londres. Fernández Madrid desempeñaba el cargo de Ministro Plenipotenciario de Colombia ante el Gobierno de Su Majestad Británica y Bello estuvo por algún tiempo al frente de la secretaría de dicha misión diplomática.

  4. Screening for Ptaquiloside in Ferns: Using Herbarium Specimens for Qualitative Mapping Purposes.

    Science.gov (United States)

    Rasmussen, Lars Holm; Pedersen, Henrik AErenlund

    2017-11-01

    Ptaquiloside (PTA) is a noxious carcinogen found widespread in Bracken (Pteridium sp.) but with scattered and unresolved distribution outside the genus. The carcinogen causes Bovine Enzootic Haematuria among cattle all-over the World and is under suspicion of causing human cancers. To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after forced reaction into PtB. Optimal reaction conditions were tested using hydrochloric acid, sulphuric acid, trifluoroacetic acid (TFA), acetic acid and temperature as the experimental variables. A pair-wise test for PTA degradation in plant-press were used to explore the effect of this preservation regime. A selection of up to 50 years old Bracken herbarium specimens were tested for PTA and PtB. The methodology was applied on 21 fern species from Denmark. An optimised TFA-based method results in 30.7% higher conversion and a 1:1 reaction between PTA and PtB. Full three-dimensional resolution of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Herbarium specimens up to 50 years old can be used for explorative risk assessment of ferns using HPLC-DAD for quantification and identification. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Not dead yet: the seasonal water relations of two perennial ferns during California's exceptional drought.

    Science.gov (United States)

    Baer, Alex; Wheeler, James K; Pittermann, Jarmila

    2016-04-01

    The understory of the redwood forests of California's coast harbors perennial ferns, including Polystichum munitum and Dryopteris arguta. Unusual for ferns, these species are adapted to the characteristic Mediterranean-type dry season, but the mechanisms of tolerance have not been studied. The water relations of P. munitum and D. arguta were surveyed for over a year, including measures of water potential (Ψ), stomatal conductance (gs) and frond stipe hydraulic conductivity (K). A dehydration and re-watering experiment on potted P. munitum plants corroborated the field data. The seasonal Ψ varied from 0 to below -3 MPa in both species, with gs and K generally tracking Ψ; the loss of K rarely exceeded 80%. Quantile regression analysis showed that, at the 0.1 quantile, 50% of K was lost at -2.58 and -3.84 MPa in P. munitum and D. arguta, respectively. The hydraulic recovery of re-watered plants was attributed to capillarity. The seasonal water relations of P. munitum and D. arguta are variable, but consistent with laboratory-based estimates of drought tolerance. Hydraulic and Ψ recovery following rain allows perennial ferns to survive severe drought, but prolonged water deficit, coupled with insect damage, may hamper frond survival. The legacy effects of drought on reproductive capacity and community dynamics are unknown. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  6. Morphology and peculiar features of spores of fern species occurring in Poland

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    Elżbieta Zenkteler

    2012-12-01

    Full Text Available The morphology of fern spores collected from natural sites in Poland was examined under light microscopy. Spore samples represented 44 species in 18 genera and in 13 families. Only spores of Ophioglossaceae were obtained from the herbarium of the Adam Mickiewicz University in Poznań while the remaining samples were obtained from living plants. Spore size ranges between 20 to 75 μm and the spores of Osmunda regalis and Polypodium interjectum were found to have remarkably large dimensions. The spores are ellipsoidal, tetrahedral and spherical/globoid in shape. Their apertures are monolete or trilete types. The exine surface patterns are baculate, cristate, granulate, reticulate, tuberculate and verrucate. Pictures of the analyzed spores are collected in a contrasting (size, colour table to make it easier to distinguish between species. The peculiar characters of fern spores are described after a review of major articles concerning the allergenic features of fern spores with special attention to Pteridium aquilinum whose spores and vegetative tissues revealed mutagenic and carcinogenic activity.

  7. Fungal endophyte communities in the temperate fernPolystichum munitumshow early colonization and extensive temporal turnover.

    Science.gov (United States)

    Younginger, Brett S; Ballhorn, Daniel J

    2017-08-16

    Fungal endophytes have been shown to colonize all land plants, yet surprisingly little attention has been given to their community composition in ferns. We examined the diversity and temporal turnover of fungal endophytes in foliar tissue of the temperate western sword fern, Polystichum munitum , comparing taxa in newly emerged leaflets and in the same fronds after 1 mo of exposure in the field. Utilizing next-generation sequencing, we sampled pinnae from P. munitum in spring, 2-3 d after they emerged. We additionally sampled pinnae 30 d later from the same fern blades. From these samples, we sequenced fungal DNA to characterize the initial colonization and temporal turnover of endophytes in the host. We demonstrate that P. munitum is abundantly colonized by endophytes in newly emerged foliar tissue. However, 1 mo later, the community composition undergoes a marked shift: the overall richness of endophytes increases, but the evenness of the community wanes as a single taxon, Flagellospora fusarioides , comes to dominate. We conclude that P. munitum hosts a variety of fungal endophyte taxa, similarly to other land plants. However, the rapid shift of the endophyte community we report is an unprecedented observation. Therefore, we further conclude that repeated sampling should be the standard in endophyte studies, because single sampling events are not sufficient to capture the dynamic nature of these cryptic microfungi. © 2017 Botanical Society of America.

  8. Mitigating arsenic contamination in rice plants with an aquatic fern, Marsilea minuta.

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    Hassi, Ummehani; Hossain, Md Tawhid; Huq, S M Imamul

    2017-10-10

    Dangers of arsenic contamination are well known in human civilization. The threat increases when arsenic is accumulated in food and livestock through irrigated crops or animal food. Hence, it is important to mitigate the effects of arsenic as much as possible. This paper discusses a process for reducing the level of arsenic in different parts of rice plants with an aquatic fern, Marsilea minuta L. A pot experiment was done to study the possibility of using Marsilea minuta as a phytoremediator of arsenic. Rice and Marsilea minuta were allowed to grow together in soils. As a control, Marsilea minuta was also cultured alone in the presence and absence of arsenic (applied at 1 mg/L as irrigation water). We did not find any significant change in the growth of rice due to the association of Marsilea minuta, though it showed a reduction of approximately 58.64% arsenic accumulation in the roots of rice grown with the association of fern compared to that grown without fern. We measured a bioaccumulation factor (BF) of > 5.34, indicating that Marsilea minuta could be a good phytoremediator of arsenic in rice fields.

  9. The Enrichment and Transfer of Heavy Metals for Two Ferns in Pb-Zn Tailing

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    Mai Jiajie

    2017-01-01

    Full Text Available The enrichment and transfer of 8 heavy metals of Equisetum ramosissimum and Pteris vittata growing naturally close to edge of the sewage pool in Bencun Pb-Zn Tailing, Eastern Guangdong were investigated. The results indicated that the pollution of Cd, Pb, Hg, Zn was very severe in this tailing, followed by Cu and Mn. The potential ecological risk of heavy metals was assessed to be very strong based on soil background values of Guangdong Province and at high risk according to criteria of the second grade State Soil Environmental Quality Standard, and Cd, Hg, Pb were the main factors leading to potential ecological risk. The content of 8 heavy metals in the two ferns did not reach critical content of hyperaccumulator, so neither of them was typical hyperaccumulator, but both had a certain tolerance to these heavy metal pollution. Underground parts of Pteris vittata had an enrichment coefficient above 1 and that of Equisetum ramosissimum had a value near 1, therefore the two ferns could be utilized as potential enrichment plants. The two ferns have strong adaptability to the tailing habitat and can be used as pioneers in ecological restoration of Pb-Zn tailings.

  10. De novo characterization of the gametophyte transcriptome in bracken fern, Pteridium aquilinum

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    Wickett Norman J

    2011-02-01

    Full Text Available Abstract Background Because of their phylogenetic position and unique characteristics of their biology and life cycle, ferns represent an important lineage for studying the evolution of land plants. Large and complex genomes in ferns combined with the absence of economically important species have been a barrier to the development of genomic resources. However, high throughput sequencing technologies are now being widely applied to non-model species. We leveraged the Roche 454 GS-FLX Titanium pyrosequencing platform in sequencing the gametophyte transcriptome of bracken fern (Pteridium aquilinum to develop genomic resources for evolutionary studies. Results 681,722 quality and adapter trimmed reads totaling 254 Mbp were assembled de novo into 56,256 unique sequences (i.e. unigenes with a mean length of 547.2 bp and a total assembly size of 30.8 Mbp with an average read-depth coverage of 7.0×. We estimate that 87% of the complete transcriptome has been sequenced and that all transcripts have been tagged. 61.8% of the unigenes had blastx hits in the NCBI nr protein database, representing 22,596 unique best hits. The longest open reading frame in 52.2% of the unigenes had positive domain matches in InterProScan searches. We assigned 46.2% of the unigenes with a GO functional annotation and 16.0% with an enzyme code annotation. Enzyme codes were used to retrieve and color KEGG pathway maps. A comparative genomics approach revealed a substantial proportion of genes expressed in bracken gametophytes to be shared across the genomes of Arabidopsis, Selaginella and Physcomitrella, and identified a substantial number of potentially novel fern genes. By comparing the list of Arabidopsis genes identified by blast with a list of gametophyte-specific Arabidopsis genes taken from the literature, we identified a set of potentially conserved gametophyte specific genes. We screened unigenes for repetitive sequences to identify 548 potentially-amplifiable simple

  11. De novo characterization of the gametophyte transcriptome in bracken fern, Pteridium aquilinum.

    Science.gov (United States)

    Der, Joshua P; Barker, Michael S; Wickett, Norman J; dePamphilis, Claude W; Wolf, Paul G

    2011-02-08

    Because of their phylogenetic position and unique characteristics of their biology and life cycle, ferns represent an important lineage for studying the evolution of land plants. Large and complex genomes in ferns combined with the absence of economically important species have been a barrier to the development of genomic resources. However, high throughput sequencing technologies are now being widely applied to non-model species. We leveraged the Roche 454 GS-FLX Titanium pyrosequencing platform in sequencing the gametophyte transcriptome of bracken fern (Pteridium aquilinum) to develop genomic resources for evolutionary studies. 681,722 quality and adapter trimmed reads totaling 254 Mbp were assembled de novo into 56,256 unique sequences (i.e. unigenes) with a mean length of 547.2 bp and a total assembly size of 30.8 Mbp with an average read-depth coverage of 7.0×. We estimate that 87% of the complete transcriptome has been sequenced and that all transcripts have been tagged. 61.8% of the unigenes had blastx hits in the NCBI nr protein database, representing 22,596 unique best hits. The longest open reading frame in 52.2% of the unigenes had positive domain matches in InterProScan searches. We assigned 46.2% of the unigenes with a GO functional annotation and 16.0% with an enzyme code annotation. Enzyme codes were used to retrieve and color KEGG pathway maps. A comparative genomics approach revealed a substantial proportion of genes expressed in bracken gametophytes to be shared across the genomes of Arabidopsis, Selaginella and Physcomitrella, and identified a substantial number of potentially novel fern genes. By comparing the list of Arabidopsis genes identified by blast with a list of gametophyte-specific Arabidopsis genes taken from the literature, we identified a set of potentially conserved gametophyte specific genes. We screened unigenes for repetitive sequences to identify 548 potentially-amplifiable simple sequence repeat loci and 689 expressed

  12. Different leaf cost-benefit strategies of ferns distributed in contrasting light habitats of sub-tropical forests.

    Science.gov (United States)

    Zhu, Shi-Dan; Li, Rong-Hua; Song, Juan; He, Peng-Cheng; Liu, Hui; Berninger, Frank; Ye, Qing

    2016-03-01

    Ferns are abundant in sub-tropical forests in southern China, with some species being restricted to shaded understorey of natural forests, while others are widespread in disturbed, open habitats. To explain this distribution pattern, we hypothesize that ferns that occur in disturbed forests (FDF) have a different leaf cost-benefit strategy compared with ferns that occur in natural forests (FNF), with a quicker return on carbon investment in disturbed habitats compared with old-growth forests. We chose 16 fern species from contrasting light habitats (eight FDF and eight FNF) and studied leaf functional traits, including leaf life span (LLS), specific leaf area (SLA), leaf nitrogen and phosphorus concentrations (N and P), maximum net photosynthetic rates (A), leaf construction cost (CC) and payback time (PBT), to conduct a leaf cost-benefit analysis for the two fern groups. The two groups, FDF and FNF, did not differ significantly in SLA, leaf N and P, and CC, but FDF had significantly higher A, greater photosynthetic nitrogen- and phosphorus-use efficiencies (PNUE and PPUE), and shorter PBT and LLS compared with FNF. Further, across the 16 fern species, LLS was significantly correlated with A, PNUE, PPUE and PBT, but not with SLA and CC. Our results demonstrate that leaf cost-benefit analysis contributes to understanding the distribution pattern of ferns in contrasting light habitats of sub-tropical forests: FDF employing a quick-return strategy can pre-empt resources and rapidly grow in the high-resource environment of open habitats; while a slow-return strategy in FNF allows their persistence in the shaded understorey of old-growth forests. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers

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    Su Ying-Juan

    2011-04-01

    Full Text Available Abstract Background The rpoB-psbZ (BZ region of some fern plastid genomes (plastomes has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. Results A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii the trnY-trnE intergenic spacer (IGS of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv ycf66 has independently lost at least four times in ferns. Conclusions Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS.

  14. Different slopes of a mountain can determine the structure of ferns and lycophytes communities in a tropical forest of Brazil

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    FELIPE C. NETTESHEIM

    2014-03-01

    Full Text Available A community of Ferns and Lycophytes was investigated by comparing the occurrence of species on different slopes of a paleoisland in Southeastern Brazil. Our goal was to evaluate the hypothesis that slopes with different geographic orientations determine a differentiation of Atlantic Forest ferns and lycophytes community. We recorded these plants at slopes turned towards the continent and at slopes turned towards the open sea. Analysis consisted of a preliminary assessment on fern beta diversity, a Non Metric Multidimensional Scaling (NMDS and a Student t-test to confirm if sites sampling units ordination was different at each axis. We further used the Pearson coefficient to relate fern species to the differentiation pattern and again Student's t-test to determine if richness, plant cover and abundance varied between the two sites. There was a relatively low number of shared species between the two sites and ferns and lycophytes community variation was confirmed. Some species were detected as indicators of the community variation but we were unable to detect richness, plant cover or abundance differences. Despite the evidence of this variation between the slopes, further works are needed to evaluate which processes are contributing to determine this pattern.

  15. Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

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    Alan M Friedlander

    Full Text Available The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA, in Desventuradas, the laminarian kelp (Eisenia cokeri, which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC, in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

  16. Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

    Science.gov (United States)

    Friedlander, Alan M; Ballesteros, Enric; Caselle, Jennifer E; Gaymer, Carlos F; Palma, Alvaro T; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

    2016-01-01

    The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

  17. Edge effects on understory epiphytic ferns and epiphyllous bryophytes in moist afromontane forests of Ethiopia

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    Hylander Kristoffer

    2013-12-01

    Full Text Available Most studies on edge effects in tropical forests have been conducted in landscapes with low human population density and in situations where the edges have been left unused after logging of the adjacent area. Here we studied forest margins heavily used by local farmers in a forest/agriculture mosaic landscape in Ethiopia. We compared forest structure and plant species composition across 41 forest-agriculture ecotones from 200 m out into the agricultural area to 200 m into the forest. There are strong edge effects from the edge and into the forest on canopy cover and number of stumps and apparently these forest-agricultural edges are intensively used by humans. They are penetrated by paths, beehives are found in the trees, timber of various dimensions is harvested and there is sometimes substantial cover of perennial wild (or semi-wild crops such as coffee and spices. The number of understory epiphytic fern species as well as number of epiphyllous (i.e., growing on leaves bryophyte species was lower at 20 m than at 75 m from the edge. The number of fern species was higher in newly created edges and thereafter they declined, which indicates an extinction debt. This pattern was not seen for the epiphyllous bryophytes. It is likely that different human management activities are responsible for many of the found edge effects besides wind and sun effects from the edge. Tropical forest margins provide important resources for people in many landscapes. It is important to understand how such use affects the biota of the forests. This study shows that there are substantial edge effects, but that the edge effects do not seem to become worse over time for epiphyllous bryophytes and only slightly so for ferns.

  18. Origins and diversity of a cosmopolitan fern genus on an island archipelago.

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    Wolf, Paul G; Rowe, Carol A; Der, Joshua P; Schilling, Martin P; Visger, Clayton J; Thomson, John A

    2015-10-20

    Isolated oceanic islands are characterized by patterns of biological diversity different from that on nearby continental mainlands. Isolation can provide the opportunity for evolutionary divergence, but also set the stage for hybridization between related taxa arriving from different sources. Ferns disperse by haploid spores, which are produced in large numbers and can travel long distances in air currents, enabling these plants to become established on most oceanic islands. Here, we examine the origins and patterns of diversity of the cosmopolitan fern genus Pteridium (Dennstaedtiaceae; bracken) on the Galapagos Islands. We use nucleotide sequences from two plastid genes, and two nuclear gene markers, to examine phylogeography of Pteridium on the Galapagos Islands. We incorporate data from a previous study to provide a worldwide context. We also sampled new specimens from South and Central America. We used flow cytometry to estimate genome size of some accessions. We found that both plastid and nuclear haplotypes fall into two distinct clades, consistent with a two-diploid-species taxonomy of P. aquilinum and P. esculentum. As predicted, the allotetraploid P. caudatum possesses nuclear haplotypes from both diploid species. Samples from the Galapagos include P. esculentum subsp. arachnoideum, P. caudatum and possible hybrids between them. Multiple Pteridium taxa were also observed growing together at some sites. We find evidence for multiple origins of Pteridium on the Galapagos Islands and multiple origins of tetraploid P. caudatum throughout its range in Central and South America. We also posit that P. caudatum may include recent diploid hybrids, backcrosses to P. esculentum, as well as allotetraploid plants. The Galapagos Islands are positioned close to the equator where they can receive dispersing propagules from both hemispheres. This may partly explain the high levels of diversity found for this cosmopolitan fern on these islands. Published by Oxford

  19. Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal.

    Science.gov (United States)

    Korall, Petra; Pryer, Kathleen M

    2014-02-01

    Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana. Tropics, subtropics and south-temperate areas of the world. The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast. Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila , Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera . The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal

  20. Continental scale patterns and predictors of fern richness and phylogenetic diversity

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    Nathalie eNagalingum

    2015-04-01

    Full Text Available Because ferns have a wide range of habitat preferences and are widely distributed, they are an ideal group for understanding how diversity is distributed. Here we examine fern diversity on a broad-scale using standard and corrected richness measures as well as phylogenetic indices; in addition we determine the environmental predictors of each diversity metric. Using the combined records of Australian herbaria, a dataset of over 60,000 records was obtained for 89 genera to infer richness. A phylogenetic tree of all the genera was constructed and combined with the herbarium records to obtain phylogenetic diversity patterns. A hotspot of both taxic and phylogenetic diversity occurs in the Wet Tropics of northeastern Australia. Although considerable diversity is distributed along the eastern coast, some important regions of diversity are identified only after sample-standardization of richness and through the phylogenetic metric. Of all of the metrics, annual precipitation was identified as the most explanatory variable, in part, in agreement with global and regional fern studies. Precipitation was combined with a different variable for each different metric. For corrected richness, precipitation is combined with temperature seasonality, while correlation of phylogenetic diversity to precipitation plus radiation indicates support for the species-energy hypothesis. Significantly high and significantly low phylogenetic diversity were found in geographically separate areas. These areas are correlated with different climatic conditions such as seasonality in precipitation. The use of phylogenetic metrics identifies additional areas of significant diversity, some of which have not been revealed using traditional taxonomic analyses, suggesting that different ecological and evolutionary processes have operated over the continent. Our study demonstrates that it is possible and vital to incorporate evolutionary metrics when inferring biodiversity hotspots

  1. Novel fungi from an ancient niche: cercosporoid and related sexual morphs on ferns.

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    Guatimosim, E; Schwartsburd, P B; Barreto, R W; Crous, P W

    2016-12-01

    The fern flora of the world ( Pteridophyta ) has direct evolutionary links with the earliest vascular plants that appeared in the late Devonian. Knowing the mycobiota associated to this group of plants is critical for a full understanding of the Fungi. Nevertheless, perhaps because of the minor economic significance of ferns, this niche remains relatively neglected by mycologists. Cercosporoid fungi represent a large assemblage of fungi belonging to the Mycosphaerellaceae and Teratosphaeriaceae ( Ascomycota ) having cercospora-like asexual morphs. They are well-known pathogens of many important crops, occurring on a wide host range. Here, the results of a taxonomic study of cercosporoid fungi collected on ferns in Brazil are presented. Specimens were obtained from most Brazilian regions and collected over a 7-yr period (2009-2015). Forty-three isolates of cercosporoid and mycosphaerella-like species, collected from 18 host species, representing 201 localities, were studied. This resulted in a total of 21 frond-spotting taxa, which were identified based on morphology, ecology and sequence data of five genomic loci (actin, calmodulin, ITS, LSU and partial translation elongation factor 1-α). One novel genus ( Clypeosphaerella ) and 15 novel species ( Cercospora samambaiae , Clypeosphaerella sticheri , Neoceratosperma alsophilae , N. cyatheae , Paramycosphaerella blechni , Pa. cyatheae , Pa. dicranopteridis-flexuosae , Pa. sticheri , Phaeophleospora pteridivora , Pseudocercospora brackenicola , Ps. paranaensis , Ps. serpocaulonicola , Ps. trichogena , Xenomycosphaerella diplazii and Zasmidium cyatheae ) are introduced. Furthermore, 11 new combinations ( Clypeosphaerella quasiparkii , Neoceratosperma yunnanensis , Paramycosphaerella aerohyalinosporum , Pa. dicranopteridis , Pa. gleicheniae , Pa. irregularis , Pa. madeirensis , Pa. nabiacense , Pa. parkii , Pa. pseudomarksii and Pa. vietnamensis ) are proposed . Finally, nine new host associations are recorded for the

  2. Population genetic variation in the tree fern Alsophila spinulosa (Cyatheaceae: effects of reproductive strategy.

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    Ting Wang

    Full Text Available BACKGROUND: Essentially all ferns can perform both sexual and asexual reproduction. Their populations represent suitable study objects to test the population genetic effects of different reproductive systems. Using the diploid homosporous fern Alsophila spinulosa as an example species, the main purpose of this study was to assess the relative impact of sexual and asexual reproduction on the level and structure of population genetic variation. METHODOLOGY/PRINCIPAL FINDINGS: Inter-simple sequence repeats analysis was conducted on 140 individuals collected from seven populations (HSG, LCH, BPC, MPG, GX, LD, and ZHG in China. Seventy-four polymorphic bands discriminated a total of 127 multilocus genotypes. Character compatibility analysis revealed that 50.0 to 70.0% of the genotypes had to be deleted in order to obtain a tree-like structure in the data set from populations HSG, LCH, MPG, BPC, GX, and LD; and there was a gradual decrease of conflict in the data set when genotypes with the highest incompatibility counts were successively deleted. In contrast, in population ZHG, only 33.3% of genotypes had to be removed to achieve complete compatibility in the data set, which showed a sharp decline in incompatibility upon the deletion of those genotypes. All populations examined possessed similar levels of genetic variation. Population ZHG was not found to be more differentiated than the other populations. CONCLUSIONS/SIGNIFICANCE: Sexual recombination is the predominant source of genetic variation in most of the examined populations of A. spinulosa. However, somatic mutation contributes most to the genetic variation in population ZHG. This change of the primary mode of reproduction does not cause a significant difference in the population genetic composition. Character compatibility analysis represents an effective approach to separate the role of sexual and asexual components in shaping the genetic pattern of fern populations.

  3. León Fernández Bonilla y la historiografía costarricense.

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    Juan Rafael Quesada Camacho

    2011-08-01

    Full Text Available Se ha afirmado, con gran justicia que León Fernández Bonilla fue el fundador del Archivo Nacional, “granero” del historiador”, según la hermosa metáfora de Lucien Febvre. En efecto, don León, como se ha acostumbrado llamarlo, ocupó un lugar de primer orden en el origen de los estudios históricos en Costa Rica. ¿En qué contexto se dio su contribución a la historiografía costarricense?

  4. Electrophoretic Evidence for Genetic Diploidy in the Bracken Fern (Pteridium aquilinum).

    Science.gov (United States)

    Wolf, P G; Haufler, C H; Sheffield, E

    1987-05-22

    Analysis of isozyme variability demonstrates that bracken fern (Pteridium aquilinum) has a diploid genetic system and expresses solely disomic inheritance patterns. Electrophoretic data indicate that genetically variable progeny are produced in natural populations after intergametophytic mating rather than by a process involving recombination between duplicated unlinked loci. Although some enzymes are encoded by more than one locus, this has resulted from subcellular compartmentalization of isozymes, and there is no evidence of extensive gene duplication resulting from polyploidy. The conclusions reached in this report differ from those which propose polyploidy as an adaptive mechanism for maintaining genetic variability in Pteridium and other homosporous pteridophytes.

  5. Aquilide A, a new mutagenic compound isolated from bracken fern (Pteridium aquilinum (L.) Kuhn).

    Science.gov (United States)

    van der Hoeven, J C; Lagerweij, W J; Posthumus, M A; van Veldhuizen, A; Holterman, H A

    1983-12-01

    A mutagenic compound, designated aquilide A, was isolated and identified from bracken fern (Pteridium aquilinum (L.) Kuhn). Aquilide A was found to be responsible for greater than 50% of the mutagenic activity observed after incubation of the methanol extract at alkaline conditions. This compound was found to be a potent genotoxic compound in mammalian cells in vitro and therefore, may be responsible for at least part of the carcinogenic activity of bracken. The instability of aquilide A under conditions normally encountered during analytical chemical procedures may explain why so many efforts to elucidate the carcinogenic factor(s) present in bracken have been unsuccessful.

  6. Clastogenic effect of bracken fern (Pteridium aquilinum v. arachnoideum) diet in peripheral lymphocytes of human consumers: preliminary data.

    Science.gov (United States)

    Recouso, R C; Stocco dos Santos, R C; Freitas, R; Santos, R C; de Freitas, A C; Brunner, O; Beçak, W; Lindsey, C J

    2003-03-01

    Ingestion of bracken fern (Pteridium aquilinum v. arachnoideum) is associated with digestive tract cancer in different regions of Japan, Venezuela and Brazil. In view of reports that dietary bracken fern causes chromosomal instability in cattle, the clastogenic effect of bracken fern was investigated, in a preliminary study, in peripheral lymphocytes obtained from habitual consumers and a control group of non-consumers, which were carefully investigated about cancer history or family cancer history, negative in both cases, using protocols comparable to those previously described in studies in cattle raised on bracken pastures. Cytogenetic analysis showed significant increased levels of chromosomal abnormalities, such as chromatid breaks, in cultured peripheral lymphocytes of the consumer group. There was no correlation with subjects, gender, smoking habits or alcohol consumption, and the only correlation was with prolonged exposure to dietary bracken.

  7. Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica.

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    Sosa, Victoria; Ornelas, Juan Francisco; Ramírez-Barahona, Santiago; Gándara, Etelvina

    2016-01-01

    Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant

  8. The physiological resilience of fern sporophytes and gametophytes: advances in water relations offer new insights into an old lineage

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    Jarmila ePittermann

    2013-08-01

    Full Text Available Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have fo-cused on the physiological capacity and stress tolerance of both the sporophyte and the gameto-phyte generations. In this review, we examine these insights through the lens of plant water rela-tions, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and vari-ously sized megaphylls are shared between ferns and more derived lineages, and offer an oppor-tunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gameto-phyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic.

  9. The physiological resilience of fern sporophytes and gametophytes: advances in water relations offer new insights into an old lineage

    Science.gov (United States)

    Pittermann, Jarmila; Brodersen, Craig; Watkins, James E.

    2013-01-01

    Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have focused on the physiological capacity and stress tolerance of both the sporophyte and the gametophyte generations. In this review, we examine these insights through the lens of plant water relations, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and variously sized megaphylls are shared between ferns and more derived lineages, and offer an opportunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gametophyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic. PMID:23935601

  10. Progressive migration and anagenesis in Drimys confertifolia of the Juan Fernández Archipelago, Chile.

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    López-Sepúlveda, Patricio; Takayama, Koji; Greimler, Josef; Crawford, Daniel J; Peñailillo, Patricio; Baeza, Marcelo; Ruiz, Eduardo; Kohl, Gudrun; Tremetsberger, Karin; Gatica, Alejandro; Letelier, Luis; Novoa, Patricio; Novak, Johannes; Stuessy, Tod F

    2015-01-01

    A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity. We investigate speciation in Drimys confertifolia, endemic to the two major islands of the Juan Fernández Archipelago, Chile, to determine genetic consequences of anagenesis, to examine relationships among populations of D. confertifolia and the continental species D. winteri and D. andina, and to test probable migration routes between the major islands. Population genetic analyses were conducted using AFLPs and nuclear microsatellites of 421 individuals from 42 populations from the Juan Fernández islands and the continent. Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor. The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape. Analysis of the probability of migration within the archipelago confirms colonization from the older island, Robinson Crusoe, to the younger island Alejandro Selkirk.

  11. Leaf micromorphology of four medicinal ferns species in Tasik Chini, Pahang

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    Nurnida, M. K., E-mail: nurnidakamal@gmail.com; Noraini, T.; Ruzi, A. R.; Idris, S. [School of Environmental and Natural Resource Sciences Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2015-09-25

    A leaf micromorphology study was conducted on four selected medicinal ferns species in Tasik Chini, Pahang. The four chosen species were Adiantum latifolium Lam., Lygodium flexuosum (L.) Sw., Lygodium microphyllum (Cav.) R. Br. and Tectaria singaporeana (Wall.) Ching. The objective of this study is to identify the leaf micromorphological characteristics that can be used as supportive scientific data especially in authentification of medicinal ferns species. The procedures involved such as dehydration, critical point drying, gold coated and examination under scanning electron microscope. Results in this study have shown some similarities and variations in the leaf micromorphological characteristics such as presence of cuticular striation, type of epicuticular waxes, structural feature of stomata and also in the presence or absence and type of trichomes. Four types of epicuticular waxes and only one type of trichome were observed, that were specific for some species. As a conclusion, the results of this study definitely proven that leaf micromorphology can be used for species authentification and might useful as preliminary scientific data for future references and further study.

  12. El blocao (y el bloqueo de José Díaz Fernández

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    Luis Fernando Bueno Morillas

    2015-06-01

    Full Text Available El blocao (1928 fue la primera novela de José Díaz Fernández. Supuso un éxito editorial insólito hasta entonces porque reunía tres características novedosas: una actitud crítica ante la guerra de Marruecos, una integración de las novedades vanguardistas en la que su autor llamó literatura de avanzada y un posicionamiento del intelectual al lado de las reivindicaciones del pueblo. Sin embargo, aunque publicó otra novela un año después (La Venus mecánica, un libro teórico en el que definía la literatura que él propugnaba y practicaba (El nuevo romanticismo y algunas narraciones breves, Díaz Fernández se bloqueó y dejó la literatura narrativa que tan buenas expectativas levantó. Analizaremos las posibles causas de ese bloqueo.

  13. Nutrient values and bioactivities of the extracts from three fern species in China: a comparative assessment.

    Science.gov (United States)

    Qi, Guoyuan; Yang, Liuqing; Xiao, Chunxia; Shi, Jing; Mi, Yashi; Liu, Xuebo

    2015-09-01

    Pteridium aquilinum, Osmunda cinnamomea Linn, and Athyrium multidentatum (Doll.) Ching are three fern species widely consumed as potherbs and traditional medicinal herbs in China. Nevertheless, no detailed comparative assessments of their nutrient values and bioactivities have been reported. In this paper, we examined the nutrient content of these ferns and the bioactivities of their extracts with a comparative method. The results indicated that they were nutrient dense for proteins, carbohydrates, fat and minerals. Compared with Pteridium aquilinum and Osmunda cinnamomea Linn, the extract from Athyrium multidentatum (Doll.) Ching was found to possess the strongest antioxidant activity, protective effects on biomolecules, cellular antioxidant activity, and antiproliferative effects owing to its highest total phenolic (476.52 ± 11.26 mg GAE per g extract) and total flavonoid (924.81 ± 4.25 mg RNE per g extract) contents. Further, Athyrium multidentatum (Doll.) Ching can lead to caspase-3 activation, poly ADP-ribose polymerase cleavage, mitochondrial membrane potential (MMP) reduction and inhibition of wound-healing in a dose-dependent manner in HepG2 cells. These results demonstrate the remarkable potential of Pteridium aquilinum, Osmunda cinnamomea Linn, and Athyrium multidentatum (Doll.) Ching as valuable sources of nutrients and natural antioxidants, and among which Athyrium multidentatum (Doll.) Ching has potential anticancer properties.

  14. Ultrastructural and cytochemical studies on oogenesis of the fern Pteridium aquilinum.

    Science.gov (United States)

    Cao, Jian-Guo; Dai, Xi-Ling; Wang, Quan-Xi

    2012-06-01

    Egg development in Pteridium aquilinum var. latiusculum was studied using ultrastructural and cytochemical methods to examine structural features influencing fertilization in leptosporangiate ferns. Ultrastructural observations indicate a separation cavity is first formed above the egg during oogenesis with a pore region persistently connecting the egg and the ventral canal cell. The egg envelope is formed by deposition of amorphous materials in the separation cavity on the outer surface of plasmalemma. The egg envelope was not formed across the pore region; instead, a fertilization pore was formed. During oogenesis, the egg nucleus produced extensive evaginations containing osmiophilic bodies. Cytochemical experiments revealed that the egg envelope displays strong periodic acid-Schiff reaction indicative of polysaccharides, with negligible Sudan black B staining for lipids, suggesting that the egg envelope is composed principally of polysaccharides, and not lipids. The present manuscript provides new insights into egg structure and development of Pteridium, including discovery and characterization of the fertilization pore and observations on the chemical nature of the egg envelope, thus contributing to the understanding of the cytological mechanism of the sexual reproduction of ferns.

  15. Ceratopteris richardii (C-fern: A model for investigating adaptive modification of vascular plant cell walls

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    Olivier eLeroux

    2013-09-01

    Full Text Available Plant cell walls are essential for most aspects of plant growth, development, and survival, including cell division, expansive cell growth, cell-cell communication, biomechanical properties, and stress responses. Therefore, characterising cell wall diversity contributes to our overall understanding of plant evolution and development. Recent biochemical analyses, concomitantly with whole genome sequencing of plants located at pivotal points in plant phylogeny, have helped distinguish between homologous characters and those which might be more derived. Most plant lineages now have at least one fully sequenced representative and although genome sequences for fern species are in progress they not yet available this group. Ferns offer key advantages for the study of developmental processes leading to vascularisation and complex organs as well as the specific differences between diploid sporophyte tissues and haploid gametophyte tissues and the interplay between them. Ceratopteris richardii has been well investigated building a body of knowledge which combined with the genomic and biochemical information available for other plants will progress our understanding of wall diversity and its impact on evolution and development.

  16. Sector analysis and predictive modelling reveal iterative shoot-like development in fern fronds.

    Science.gov (United States)

    Sanders, Heather L; Darrah, Peter R; Langdale, Jane A

    2011-07-01

    Plants colonized the terrestrial environment over 450 million years ago. Since then, shoot architecture has evolved in response to changing environmental conditions. Our current understanding of the innovations that altered shoot morphology is underpinned by developmental studies in a number of plant groups. However, the least is known about mechanisms that operate in ferns--a key group for understanding the evolution of plant development. Using a novel combination of sector analysis, conditional probability modelling methods and histology, we show that shoots, fronds ('leaves') and pinnae ('leaflets') of the fern Nephrolepis exaltata all develop from single apical initial cells. Shoot initials cleave on three faces to produce a pool of cells from which individual frond apical initials are sequentially specified. Frond initials then cleave in two planes to produce a series of lateral merophyte initials that each contributes a unit of three pinnae to half of the mediolateral frond axis. Notably, this iterative pattern in both shoots and fronds is similar to the developmental process that operates in shoots of other plant groups. Pinnae initials first cleave in two planes to generate lateral marginal initials. The apical and marginal initials then divide in three planes to coordinately generate the determinate pinna. These findings impact both on our understanding of fundamental plant developmental processes and on our perspective of how shoot systems evolved.

  17. Association of water-borne conidial fungi with epiphytic tree fern (Drynaria quercifolia

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    Kishore S. Karamchand

    2013-12-01

    Full Text Available The live and dead tissues, and trapped leaf litter by the epiphytic tree fern Drynaria quercifolia associated with riparian tree species of Konaje (west coast and Sampaje (Western Ghat streams of India during dry (summer and wet (monsoon seasons yielded 37 species of water-borne conidial fungi on bubble chamber incubation. Dead bracket leaves of fern possess the highest species as well as conidia in Konaje, while the trapped leaf litter in Sampaje. During summer, the diversity was highest in bracket leaves in both locations, while in monsoon season it was highest in rhizomes of Konaje and in trapped leaf litter in Sampaje. Even though the conidial output from tissues of Drynaria and trapped leaf litter were not equivalent to stream submerged leaf litter, the species richness ranged between 40% and 75% in Konaje and Sampaje streams. As stable epiphyte, Drynaria exposed to wet and dry regimes in tree canopies of west coast and Western Ghats likely to serve as host for perfect states of water-borne hyphomycetes.

  18. Mutation induction of blechnum gibium a fern species through in vitro propagation

    International Nuclear Information System (INIS)

    Azhar Mohamad; Amran Abd Halim; Rusli Ibrahim

    2002-01-01

    Blechnum gibum is a fern with beutiful symmetry and unique palm-like appearance. Mutation induction is an alternative way to increase its variability in characteristics. Information on the radiosensitivity test is an important factor in deciding the approach to be taken for genetic changes of the fern in mutation breeding. Plantlets of B. gibum were irradiated with doses of 0, 10, 20, 40, 60, 80, 100 and 150 Gy using a gamma cell with a 60 Co source at dose rate of 0.25 Gy s -1 . . Irradiated plantlets were cultured on semi solid modified hormone free Murashige and Skoog (MS) media and incubated at 24 degree C with a photoperiod of 16 hours (3500 lux). Radiosensitivity was assessed by the survival rate 7 weeks after the treatment. Increasing gamma ray doses caused a reduction of survival rate as well as the number of fronds produced per plantlet. LD 50 for B. gibum was 54 Gy as estimated from the dose rate vs survival curve. Regenerated plantlets from treated plantlets showed a stunted and slow recovery growth especially for higher doses as compared to control plantlets. (Author)

  19. Conservation assessment for southern maidenhair fern and stream orchid in the Black Hills National Forest South Dakota and Wyoming

    Science.gov (United States)

    J. Hope Hornbeck; Deanna J. Reyher; Carolyn Hull Sieg; Reed W. Crook

    2003-01-01

    Southern maidenhair fern (Adiantum capillus-veneris L.; Pteridaceae) is a cosmopolitan species that is widely distributed in southern North America. Stream orchid (Epipactis gigantea Dougl. ex Hook.; Orchidaceae) occurs in western North America from British Columbia, Canada; south to California, Arizona and New Mexico; and east to...

  20. Epiphytic ferns in swamp forest remnants of the coastal plain of southern Brazil: latitudinal effects on the plant community

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    Letícia S. Machado

    Full Text Available ABSTRACT Community structure and spatial distribution of epiphytic ferns in swamp forest remnants along the coastal plain of the state of Rio Grande do Sul were analyzed. A total of 440 trees were sampled in fifty-seven 10 x 10 m plots. Each phorophyte was divided into five ecological zones (strata, where all species of epiphytic ferns were recorded. A total of 34 species representing 18 genera in six families were recorded. Polypodiaceae was the most represented family with 17 species, and Microgramma vacciniifolia had the highest epiphytic importance value. Characteristic holoepiphyte was the predominant ecological category, representing 70 % of the species. Ordination analysis showed a gradual change in floristic composition between ecological zones with richness differing significantly between strata. We observed that with increasing latitude there was a decrease in mean temperature and total rainfall, but an increase in frosts. These climatic and phytogeography changes result in a reduction in species richness and a change in the structure of epiphytic fern communities in a north-to-south direction. The importance of swamp forest remnants of the coastal plain to the diversity of epiphytic ferns is discussed.

  1. Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae caudices in Rio Grande do Sul, Brazil

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    JL. Schmitt

    Full Text Available The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39% and in the genus Asplenium L. (22%. Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5 was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

  2. Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae) caudices in Rio Grande do Sul, Brazil.

    Science.gov (United States)

    Schmitt, J L; Windisch, P G

    2010-08-01

    The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39%) and in the genus Asplenium L. (22%). Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5) was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

  3. The nucleotide sequences of 5S rRNAs from a fern Dryopteris acuminata and a horsetail Equisetum arvense.

    Science.gov (United States)

    Hori, H; Osawa, S; Takaiwa, F; Sugiura, M

    1984-02-10

    The nucleotide sequences from two Pteridophyta species, a fern Dryopteris acuminata and a horsetail Equisetum arvense have been determined. These two sequences are more related to those of the Bryophyta species (88% identity on average) than to those of seed plants (84% identity on average).

  4. Do ferns and lycophytes function as medicinal plants? A study of their low representation in traditional pharmacopoeias.

    Science.gov (United States)

    Reinaldo, Rafael Corrêa Prota dos Santos; Santiago, Augusto César Pessôa; Medeiros, Patrícia Muniz; Albuquerque, Ulysses Paulino

    2015-12-04

    Ethnobotany is becoming an important tool for understanding how traditional medical systems are organized and which variables affect their structure and dynamics. However, some phenomena observed in ethnobotanical studies led us to question whether such phenomena are real or methodological artifacts. The small proportion of ferns and lycophytes in ethnobotanical surveys of medicinal plants is one such phenomenon, and its causes should be identified using different approach levels. The present study aimed to clarify the reasons for a low representation of these two groups in studies of medicinal plants. The present study considered the following hypotheses: 1) ferns and lycophytes are little represented in different ethnobotanical studies because of inadequate data collection methods to record these species; 2) ferns and lycophytes are little represented because of the local perception of their low therapeutic efficacy; and 3) species of ferns and lycophytes are represented in local pharmacopoeias in proportion to the size of their families. We chose rural communities from Chapada do Araripe, Northeast Brazil to test our hypotheses. Data on the medicinal plant repertoires of the communities and on the perceived therapeutic efficacy of ferns were obtained using two different methods, semi-structured interviews associated with free lists and a checklist interview, both applied to local specialists. The resulting data were analyzed differently for each test. In addition, data regarding the total flora x medicinal flora ratio were obtained with a floristic survey and accessing data banks from previous studies performed by our research team. All hypotheses were confirmed, showing that all three factors contributed to the low representation of these plant groups as medicinal resources. The present study showed that free-list interviews are not a good method to access traditional knowledge of medicinal ferns and lycophytes and that the use of visual stimuli can help the

  5. Host range and genetic relatedness of Colletotrichum acutatum isolates from fruit crops and leatherleaf fern in Florida.

    Science.gov (United States)

    MacKenzie, S J; Peres, N A; Barquero, M P; Arauz, L F; Timmer, L W

    2009-05-01

    Isolates of Colletotrichum acutatum were collected from anthracnose-affected strawberry, leatherleaf fern, and Key lime; ripe-rot-affected blueberry; and postbloom fruit drop (PFD)-affected sweet orange in Florida. Additional isolates from ripe-rot-affected blueberry were collected from Georgia and North Carolina and from anthracnose-affected leatherleaf fern in Costa Rica. Pathogenicity tests on blueberry and strawberry fruit; foliage of Key lime, leatherleaf fern, and strawberry; and citrus flowers showed that isolates were highly pathogenic to their host of origin. Isolates were not pathogenic on foliage of heterologous hosts; however, several nonhomologous isolates were mildly or moderately pathogenic to citrus flowers and blueberry isolates were pathogenic to strawberry fruit. Based on sequence data from the internal transcribed spacer (ITS)1-5.8S rRNA-ITS2 region of the rDNA repeat, the glutaraldehyde-3-phosphate dehydrogenase intron 2 (G3PD), and the glutamine synthase intron 2 (GS), isolates from the same host were identical or very similar to each other and distinct from those isolated from other hosts. Isolates from leatherleaf fern in Florida were the only exception. Among these isolates, there were two distinct G3PD and GS sequences that occurred in three of four possible combinations. Only one of these combinations occurred in Costa Rica. Although maximum parsimony trees constructed from genomic regions individually displayed little or no homoplasy, there was a lack of concordance among genealogies that was consistent with a history of recombination. This lack of concordance was particularly evident within a clade containing PFD, Key lime, and leatherleaf fern isolates. Overall, the data indicated that it is unlikely that a pathogenic strain from one of the hosts examined would move to another of these hosts and produce an epidemic.

  6. Colombia en cuatro tiempos : Carmelo Fernández 1809-1887

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    Beatriz González

    1991-09-01

    Full Text Available San José de Guama (estado de Yaracuy, Venezuela, 30 de junio de 1809 - Caracas, 9 de febrero de 1887. En 1983 a los 96 años de su muerte y dentro de las conmemoraciones de los 200 años del nacimiento de Simón Bolívar, fueron trasladados los restos del artista y militar Carmelo Fernández al Panteón Nacional de Caracas, donde reposan cercanos a los del Libertador Cuando se observa la baldosa del piso que a manera de tumba presenta su nombre, se recuerda su fidelidad y admiración por Bolívar. Nunca debió de pasar por la mente de este hombre humilde y singular que sus restos descansarían en tan notable sitio de veneración y culto.

  7. Role of glutathione in tolerance to arsenite in Salvinia molesta, an aquatic fern

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    Adinan Alves da Silva

    2017-09-01

    Full Text Available ABSTRACT In many plant species, tolerance to toxic metals is highly dependent on glutathione, an essential metabolite for cellular detoxification. We evaluated the responses of glutathione metabolism to arsenite (AsIII in Salvinia molesta, an aquatic fern that has unexplored phytoremediation potential. Plants were exposed to different AsIII concentrations in nutrient solution for 24 h. AsIII caused cell membrane damage to submerged leaves, indicating oxidative stress. There was an increase in the glutathione content and ϒ-glutamylcysteine synthetase enzyme activity in the submerged and floating leaves. The glutathione peroxidase and glutathione sulfotransferase enzymes also showed increased activity in both plant parts, whereas glutathione reductase only showed increased activity in the submerged leaves. These findings suggest an important role for glutathione in the protection of S. molesta against the toxic effects of AsIII, with more effective tolerance responses in the floating leaves.

  8. Observations on the microanatomy of the spermatozoid of the bracken fern (Pteridium aquilinum).

    Science.gov (United States)

    MANTON, I

    1959-12-01

    Salient features of structure of the spermatozoid of a fern (Pteridium aquilinum) have been determined by a combination of visual and ultraviolet microscopy, with electron microscopy of shadow-cast whole mounts and thin sections, using magnifications up to but not exceeding 50,000 diameters. Attention has been concentrated on the arrangement rather than on the internal details of the various parts. The most important component, apart from the spirally wound nucleus, numerous (about 40) cilia, and mitochondria, is a sheet of parallel fibres spirally wound near the surface of a cone of cytoplasm to which all the other major components are in various ways attached. The diameter of the individual fibres is of the order of 200 A. A few details are given of other minor cell constituents including additional mechanical materials, starch-containing leucoplasts, and the smaller cytoplasmic inclusions.

  9. Transgressive intimacy in the fiction of Costamagna, Fernández, Jeftanovic, Maturana and Meruane

    Directory of Open Access Journals (Sweden)

    Nan Zheng

    2017-11-01

    Full Text Available The present work, framed primarily in the discourse of intimacy, Jacques Rancière’s theory of the aesthetic regime of art and Wendy Brow's revision of Foucault's reflecctions on Neoliberalism, examines the chilean fictions of the last two decades by Alejandra Costamagna, Nona Fernández, Andrea Jeftanovic, Andrea Maturana and Lina Meruane. The literary production of these female writers disagrees with patriarchal norms and those established by the neoliberal rationality dominated by the homo oeconomicus. This article analyzes the possibility of classifying these writers as a new literary generation of the post-dictatorship, which could be more inconvenient than benefical, since it would represent a gesture which could be establishing divisions between feminine and masculine; private and public; the sublime in art and the banality of everyday life.

  10. Toxicity of Diclofenac in the Fern Azolla filiculoides and the Lichen Xanthoria parietina.

    Science.gov (United States)

    Vannini, Andrea; Paoli, Luca; Vichi, Marco; Bačkor, Martin; Bačkorová, Miriam; Loppi, Stefano

    2018-03-01

    This study investigated the occurrence of toxicity, expressed as damage to the photosynthetic apparatus, in the aquatic fern Azolla filiculoides and the lichen Xanthoria parietina following treatments with diclofenac at different concentrations (0.1, 1, 10 and 100 mg/L) and different exposure times (24, 48, 72 and 240 h). Measurements of photosynthetic efficiency, chlorophyll content and chlorophyll degradation indicated dose- and time-dependent toxicity, since significant differences with control samples as well as among treatments, emerged mainly for the highest concentration (100 mg/L) and the longest time (240 h). In addition, also the mycobiont of the lichen X. parietina showed similar toxic effects, expressed as ergosterol content. The absence of relevant alterations at the lowest concentration (0.1 mg/L) suggested a very limited susceptibility of these species to environmentally relevant levels of this pharmaceutical.

  11. Phylogeny of the fern subfamily Pteridoideae (Pteridaceae; Pteridophyta), with the description of a new genus: Gastoniella.

    Science.gov (United States)

    Zhang, Liang; Zhou, Xin-Mao; Lu, Ngan Thi; Zhang, Li-Bing

    2017-04-01

    As the second most genera-rich fern family, Pteridaceae contain more than 1000 species contributing to ca. 10% of extant leptosporangiate fern diversity. The subfamily Pteridoideae is one of the five subfamilies often recognized. The circumscription of Pteridoideae has not been clear. A large number of species have not yet been included in any molecular analyses before. In this study, DNA sequences of six plastid loci of 154 accessions representing ca. 87 species in 14 genera of Pteridaceae subfam. Pteridoideae and four accessions representing two species in subfam. Parkerioideae and one species of subfam. Adiantoideae as outgroups were used to infer a phylogeny using maximum likelihood and maximum parsimony. Our analyses show that (1) Pteridoideae is monophyletic and the newly defined subfamily is composed of 14 genera including a newly described genus; (2) Pteridoideae is resolved into four strongly supported monophyletic clades: the Pteris clade, the Actiniopteris+Onychium clade, the JAPSTT clade, and the GAPCC clade, these being supported by not only molecular data but also morphological features and distribution information; (3) Onychium is confirmed as monophyletic and accessions of Onychium are resolved into two strongly supported clades, the O. cryptogrammoides clade and the O. siliculosum clade; and (4) Accessions of the traditionally defined Anogramma are resolved as paraphyletic in relation to Cerosora, Cosentinica, and Pityrogramma. Three species traditionally treated in Anogramma are in fact more closely related to Cerosora and Pityrogramma than they are to Anogramma. Gastoniella Li Bing Zhang & Liang Zhang, gen. nov. is described to accommodate these species and three new combinations are provided. Three currently known species of Gastoniella are distributed in the Ascension Island in South Atlantic Ocean, central Mexico, and tropical America, respectively. The new genus is distinct from Anogramma s.s. in having ultimate segments linear not obviously

  12. Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica

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    Victoria Sosa

    2016-11-01

    Full Text Available Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Methods Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Results Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from

  13. Detection and mapping the spatial distribution of bracken fern weeds using the Landsat 8 OLI new generation sensor

    Science.gov (United States)

    Matongera, Trylee Nyasha; Mutanga, Onisimo; Dube, Timothy; Sibanda, Mbulisi

    2017-05-01

    Bracken fern is an invasive plant that presents serious environmental, ecological and economic problems around the world. An understanding of the spatial distribution of bracken fern weeds is therefore essential for providing appropriate management strategies at both local and regional scales. The aim of this study was to assess the utility of the freely available medium resolution Landsat 8 OLI sensor in the detection and mapping of bracken fern at the Cathedral Peak, South Africa. To achieve this objective, the results obtained from Landsat 8 OLI were compared with those derived using the costly, high spatial resolution WorldView-2 imagery. Since previous studies have already successfully mapped bracken fern using high spatial resolution WorldView-2 image, the comparison was done to investigate the magnitude of difference in accuracy between the two sensors in relation to their acquisition costs. To evaluate the performance of Landsat 8 OLI in discriminating bracken fern compared to that of Worldview-2, we tested the utility of (i) spectral bands; (ii) derived vegetation indices as well as (iii) the combination of spectral bands and vegetation indices based on discriminant analysis classification algorithm. After resampling the training and testing data and reclassifying several times (n = 100) based on the combined data sets, the overall accuracies for both Landsat 8 and WorldView-2 were tested for significant differences based on Mann-Whitney U test. The results showed that the integration of the spectral bands and derived vegetation indices yielded the best overall classification accuracy (80.08% and 87.80% for Landsat 8 OLI and WorldView-2 respectively). Additionally, the use of derived vegetation indices as a standalone data set produced the weakest overall accuracy results of 62.14% and 82.11% for both the Landsat 8 OLI and WorldView-2 images. There were significant differences {U (100) = 569.5, z = -10.8242, p < 0.01} between the classification accuracies

  14. Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots

    NARCIS (Netherlands)

    de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schlupmann, Henriette|info:eu-repo/dai/nl/304827819; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

    The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises

  15. Laboratory results of females Nellore of different age groups from farms with and without the presence of bracken fern (Pteridium arachnoideum.

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    A. H. Q. Watanabe

    2016-05-01

    Full Text Available The Pteridium arachnoideum, previously classified as Pteridium aquilinum, popularly known as bracken fern, is one of the most preoccupying poisonous vegetables in several countries, including Brazil. Brazilian researchers characterized, experimentally, three clinic forms of diseases caused by bracken fern to cattle: bleeding diathesis, Bovine Enzootic Hematuria and squamous cell carcinoma in the digestive tracts. In the present work we studied the hematological, biochemical and urinalysis values of two different phases of the animal development being 56 calves and 55 cows from farms with similar zootechnical characteristics and with and without the presence of bracken fern. In this study there was a significant fall in the values of the hematocrit, hemoglobin and number of red blood cells in the calves from farms with the presence of bracken fern, however, for the group of cows there was a fall only in the number of red blood cells compared to the group of animals from farms without the presence of bracken fern. The number of Platelets was significantly superior in all of the age groups of animals from farms with bracken fern. There were no significant alterations in the leucocyte count indicating that there was no systemic inflammatory response in any of the two categories

  16. Hematuria and urinary bladder lesions compatible with bracken fern (Pteridium aquilinum) intoxication in captive fallow deer (Dama dama).

    Science.gov (United States)

    Scala, Christopher; Ortiz, Katia; Catinaud, Jérôme; Lemberger, Karin

    2014-06-01

    Hemangiosarcoma, hemangioma, transitional cell carcinoma, and chronic cystitis were diagnosed in the urinary bladder of six captive fallow deer (Dama dama). Hematuria and thin body condition were observed in the advanced cases. These findings were compatible with chronic enzootic hematuria and were suspected to have been induced by chronic ingestion of bracken fern (Pteridium aquilinum) present on the premises. These lesions were similar to those described in bovine enzootic hematuria in cattle. Hemangiosarcoma metastases, hydronephrosis, and renal carcinoma were also associated in some cases. This is the first report of hemangioma, hemangiosarcoma, transitional cell carcinoma, and renal carcinoma of the urinary bladder in fallow deer and the first indication of bracken fern intoxication in deer.

  17. Effect of enhanced nitrogen input on release of nutrients and nutrient availability in stands of tall fern Athyrium distentifolium

    Science.gov (United States)

    Tå¯Ma, Ivan; Holuib, Petr; Záhora, Jaroslav; Fiala, Karel

    2010-05-01

    Improved light conditions, after destruction of tree canopy, soil acidification and increased nitrogen availability, support intensive spreading of acidophilous perennial grasses and stands of tall fern (Athyrium distentifolium) on deforested sites in the Moravian-Silesian Beskydy Mts. (the Czech Republic). The aim of the study was to determine how higher inputs of nitrogen affect the release of nutrients during decomposition processes of fern litter. The experimental site was chosen on a southwest-facing slope of the Kněhyně Mt. (49o31´ N, 18o 32´E, 1170 m a.s.l.) in the Moravian-Silesin Beskydy Mts. in the Czech Republic. The area is characterized by an annual mean air temperature of 5.6 oC and annual precipitation of 1110 mm. A large fern stand was divided in four blocks (5x3 m) and on two of them higher doses of nitrogen were applied (50 kgN/ha in five doses in the course of the growing season). Similarly, mesh-bags with fresh natural litter of fern were used to determine rate of litter decomposition during one year. Samples were inserted in both nitrogen treated and untreated fern stands in autumn 2006 and 2007 collected in autumn 2007 and 2008. On the basis of litter amount estimated at the start and at the end of exposure and of actual content of minerals in original and exposed litter, the release and/or accumulation of minerals during decomposition were calculated. The availability (more or less in the case of ammonia-nitrogen) and movement of percolated nitrogen (mainly in the case of nitrate-nitrogen) was estimated in situ by the trapping of mineral N into the ion exchange resin (IER) inserted into special cover. The decomposition rate of native A. distentifolium litter was approximately the same (29-30 %) at both nitrogen availability, however the element release from decomposed litter was higher for N, P and Ca in both years and for K and Mg in the first year as well. However, decomposition rate of cellulose was two times greater in fern stands

  18. Long-term male aggregations of Euglossa melanotricha Moure (Hymenoptera: Apidae) on fern fronds Serpocaulon triseriale (Pteridophyta: Polypodiaceae).

    Science.gov (United States)

    e Silva, Marília D; Andrade-Silva, A C R; Silva, M

    2011-10-01

    A communal dormitory of male orchid bees, Euglossa melanotricha Moure, was monitored over a one-year period, when they passed the night in the fronds of a Serpocaulon triseriale (Polypodiaceae) fern. The bees used the same fronds continuously, moving to neighboring fronds as senescence set in. As many as 49 males were observed together on any one night, clinging to the midribs on the abaxial surface of up to five fern blades with their mandibles. A number of males returned to the same site to pass the night continuously over a number of months, and were observed making physical contact with one another without provoking agonistic behavior. Males of E. melanotricha appeared to prefer sleeping at sites close to nests and potential sources of odoriferous essences, such as orchids (Orchidaceae).

  19. Air humidity as key determinant of morphogenesis and productivity of the rare temperate woodland fern Polystichum braunii.

    Science.gov (United States)

    Schwerbrock, R; Leuschner, C

    2016-07-01

    (1) Most ferns are restricted to moist and shady habitats, but it is not known whether soil moisture or atmospheric water status are decisive limiting factors, or if both are equally important. (2) Using the rare temperate woodland fern Polystichum braunii, we conducted a three-factorial climate chamber experiment (soil moisture (SM) × air humidity (RH) × air temperature (T)) to test the hypotheses that: (i) atmospheric water status (RH) exerts a similarly large influence on the fern's biology as soil moisture, and (ii) both a reduction in RH and an increase in air temperature reduce vigour and growth. (3) Nine of 11 morphological, physiological and growth-related traits were significantly influenced by an increase in RH from 65% to 95%, leading to higher leaf conductance, increased above- and belowground productivity, higher fertility, more epidermal trichomes and fewer leaf deformities under high air humidity. In contrast, soil moisture variation (from 66% to 70% in the moist to ca. 42% in the dry treatment) influenced only one trait (specific leaf area), and temperature variation (15 °C versus 19 °C during daytime) only three traits (leaf conductance, root/shoot ratio, specific leaf area); RH was the only factor affecting productivity. (4) This study is the first experimental proof for a soil moisture-independent air humidity effect on the growth of terrestrial woodland ferns. P. braunii appears to be an air humidity hygrophyte that, whithin the range of realistic environmental conditions set in this study, suffers more from a reduction in RH than in soil moisture. A climate warming-related increase in summer temperatures, however, seems not to directly threaten this endangered species. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  20. Volatile emission in bracken fern is induced by jasmonates but not by Spodoptera littoralis or Strongylogaster multifasciata herbivory.

    Science.gov (United States)

    Radhika, Venkatesan; Kost, Christian; Bonaventure, Gustavo; David, Anja; Boland, Wilhelm

    2012-01-01

    Jasmonate-mediated regulation of VOC emission has been extensively investigated in higher plants, however, only little is known about VOC production and its regulation in ferns. Here, we investigate whether the emission of VOCs from bracken fern Pteridium aquilinum is triggered by herbivory and if so - whether it is regulated by the octadecanoid signaling pathway. Interestingly, feeding of both generalist (Spodoptera littoralis) and specialist (Strongylogaster multifasciata) herbivores as well as application of singular and continuous mechanical wounding of fronds induced only very low levels of VOC emission. In contrast, treatment with jasmonic acid (JA) led to the emission of a blend of VOCs that was mainly comprised of terpenoids. Likewise, treatment with the JA precursor 12-oxo-phytodienoic acid (OPDA) and α-linolenic acid also induced VOC emission, albeit to a lower intesity than the JA treatment. Accumulation of endogenous JA was low in mechanically wounded fronds and these levels were unaffected by the application of oral secretions from both generalist or specialist herbivores. The emission of terpenoids upon JA treatment could be blocked with fosmidomycin and mevinolin, which are inhibitors of the MEP- and MVA pathways, respectively. These results indicate that similar to higher plants, terpenoid VOCs are produced via these pathways in bracken fern and that these pathways are JA-responsive. However, the very low amounts of terpenoids released after herbivory or mechanical damage are in stark contrast to what is known from higher plants. We speculate that S. multifasciata and S. littoralis feeding apparently did not induce the threshold levels of JA required for activating the MEP and MVA pathways and the subsequent volatile emission in bracken fern.

  1. Volatile emission in bracken fern is induced by jasmonates but not by Spodoptera littoralis or Strongylogaster multifasciata herbivory.

    Directory of Open Access Journals (Sweden)

    Venkatesan Radhika

    Full Text Available Jasmonate-mediated regulation of VOC emission has been extensively investigated in higher plants, however, only little is known about VOC production and its regulation in ferns. Here, we investigate whether the emission of VOCs from bracken fern Pteridium aquilinum is triggered by herbivory and if so - whether it is regulated by the octadecanoid signaling pathway. Interestingly, feeding of both generalist (Spodoptera littoralis and specialist (Strongylogaster multifasciata herbivores as well as application of singular and continuous mechanical wounding of fronds induced only very low levels of VOC emission. In contrast, treatment with jasmonic acid (JA led to the emission of a blend of VOCs that was mainly comprised of terpenoids. Likewise, treatment with the JA precursor 12-oxo-phytodienoic acid (OPDA and α-linolenic acid also induced VOC emission, albeit to a lower intesity than the JA treatment. Accumulation of endogenous JA was low in mechanically wounded fronds and these levels were unaffected by the application of oral secretions from both generalist or specialist herbivores. The emission of terpenoids upon JA treatment could be blocked with fosmidomycin and mevinolin, which are inhibitors of the MEP- and MVA pathways, respectively. These results indicate that similar to higher plants, terpenoid VOCs are produced via these pathways in bracken fern and that these pathways are JA-responsive. However, the very low amounts of terpenoids released after herbivory or mechanical damage are in stark contrast to what is known from higher plants. We speculate that S. multifasciata and S. littoralis feeding apparently did not induce the threshold levels of JA required for activating the MEP and MVA pathways and the subsequent volatile emission in bracken fern.

  2. Cyathea arjae Latiff (Cyatheaceae), A New Species of Dwarf Tree-Fern from Sayap, Mt. Kinabalu, Sabah, Malaysia

    International Nuclear Information System (INIS)

    Latiff, A.

    2015-01-01

    A dwarf tree-fern, Cyathea arjae Latiff is described as a new species from Sayap, Mt. Kinabalu, Sabah, Malaysia. This new species belongs to Schizocaena group which has basiscopic veins that originate from the costa and not from the costule. It is closely related to C. capitata in having simply pinnate fronds of which the apex is a deltoid lamina. Holttums key was modified. (author)

  3. Comparative glycan profiling of Ceratopteris richardii 'C-Fern' gametophytes and sporophytes links cell-wall composition to functional specialization.

    Science.gov (United States)

    Eeckhout, Sharon; Leroux, Olivier; Willats, William G T; Popper, Zoë A; Viane, Ronald L L

    2014-10-01

    Innovations in vegetative and reproductive characters were key factors in the evolutionary history of land plants and most of these transformations, including dramatic changes in life cycle structure and strategy, necessarily involved cell-wall modifications. To provide more insight into the role of cell walls in effecting changes in plant structure and function, and in particular their role in the generation of vascularization, an antibody-based approach was implemented to compare the presence and distribution of cell-wall glycan epitopes between (free-living) gametophytes and sporophytes of Ceratopteris richardii 'C-Fern', a widely used model system for ferns. Microarrays of sequential diamino-cyclohexane-tetraacetic acid (CDTA) and NaOH extractions of gametophytes, spores and different organs of 'C-Fern' sporophytes were probed with glycan-directed monoclonal antibodies. The same probes were employed to investigate the tissue- and cell-specific distribution of glycan epitopes. While monoclonal antibodies against pectic homogalacturonan, mannan and xyloglucan widely labelled gametophytic and sporophytic tissues, xylans were only detected in secondary cell walls of the sporophyte. The LM5 pectic galactan epitope was restricted to sporophytic phloem tissue. Rhizoids and root hairs showed similarities in arabinogalactan protein (AGP) and xyloglucan epitope distribution patterns. The differences and similarities in glycan cell-wall composition between 'C-Fern' gametophytes and sporophytes indicate that the molecular design of cell walls reflects functional specialization rather than genetic origin. Glycan epitopes that were not detected in gametophytes were associated with cell walls of specialized tissues in the sporophyte. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. La Galicia que vio nacer y crecer a Gregorio Fernández

    Directory of Open Access Journals (Sweden)

    Saavedra, Pegerto

    2010-12-01

    Full Text Available The great sculptor Gregorio Fernández was born in Galicia; that territory was very different from the city of Valladolid, where he worked and died. Fhe changes caused by the Catholici Reformation progressed slowly and with difficulty en the old Galician Kingdom. The absence of towns prevailed in that period, and most of Glaician people lived in small villages that were far from urban civilization. They were not instructed in Christian doctrine and besides they had their peculiar customs, such as feeding on brown bread and bacon. This cultural and social context generated a negative opinion about Galicia and Galician people in the middle of the XVIth century. Don Diego Samiento de Acuña, first earl of Gondomar, and Don Pedro Fernández de Castro, seventh earl of Lemos, were opposed to this negative opinion, although they had an unfortunate outcome. First, Gondomar -who owned an important library in his house in Valladolid- and his circle wrote spirited chorographical and historiographical works. On the other hand, Gondomar and Lemos presented several claims in the Royal Court from Galician nobility and clergy al the end of XVIth century and at the beginning of the XVIIth century.

    La Galicia en la que nació el formidable escultor Gregorio Fernández tenía poco que ver con la ciudad de Valladolid, en la desarrolló su trabajo y falleció. El viejo Reino gallego era un territorio ruralizado, en el que los cambios ligados a la reforma tridentina avanzaban con lentitud y dificultad. La ausencia de grandes núcleos de población y la rudeza de unos campesinos que vivían en minúsculos asentamientos dispersos, alejados de la civilización por su ignorancia de los rudimentos de la catequesis y por sus costumbres, entre ellas la de alimentarse de pan negro y tocino, son realidades que están en el origen de la caudalosa corriente de tópicos negativos que desde mediados del XVI comenzó a correr sobre el Reino y sus habitantes, y que, con poco

  5. Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns.

    Science.gov (United States)

    Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E

    2016-07-13

    Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this 'ancient' fern lineage across the tropics. © 2016 The Author(s).

  6. Arsenic accumulation by the aquatic fern Azolla: Comparison of arsenate uptake, speciation and efflux by A. caroliniana and A. filiculoides

    International Nuclear Information System (INIS)

    Zhang Xin; Lin Aijun; Zhao Fangjie; Xu Guozhong; Duan Guilan; Zhu Yongguan

    2008-01-01

    This study investigates As accumulation and tolerance of the aquatic fern Azolla. Fifty strains of Azolla showed a large variation in As accumulation. The highest- and lowest-accumulating ferns among the 50 strains were chosen for further investigations. Azolla caroliniana accumulated two times more As than Azolla filiculoides owing to a higher influx velocity for arsenate. A. filiculoides was more resistant to external arsenate due to a lower uptake. Both strains showed a similar degree of tolerance to internal As. Arsenate and arsenite were the dominant As species in both Azolla strains, with methlyated As species accounting for <5% of the total As. A. filiculoides had a higher proportion of arsenite than A. caroliniana. Both strains effluxed more arsenate than arsenite, and the amount of As efflux was proportional to the amount of As accumulation. The potential of growing Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated. - Arsenic accumulation and efflux differ between strains of the aquatic fern Azolla

  7. Inorganic and organic nitrogen acquisition by a fern Dicranopteris dichotoma in a subtropical forest in South China.

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    Xingliang Xu

    Full Text Available The fern Dicranopteris dichotoma is an important pioneer species of the understory in Masson pine (Pinus massoniana forests growing on acidic soils in the subtropical and tropical China. To improve our understanding of the role of D. dichotoma in nitrogen (N uptake of these forests, a short-term (15N experiment was conducted at mountain ridge (MR, with low N level and mountain foot (MF, with high N level. We injected (15N tracers as (15NH4, (15NO3 or (15N-glycine into the soil surrounding each plant at both MR and MF sites. Three hours after tracer injection, the fern D. dichotoma took up 15NH4+ significantly faster at MF than at MR, but it showed significantly slower uptake of (15NO3- at MF than at MR. Consequently, (15NO3- made greater contribution to the total N uptake (50% to the total N uptake at MR than at MF, but (15N-glycine only contributed around 11% at both sites. Twenty-four hours after tracer injection, D. dichotoma preferred (15NH4+ (63% at MR, whereas it preferred (15NO3- (47% at MF. We concluded that the D. dichotoma responds distinctly in its uptake pattern for three available N species over temporal and spatial scales, but mainly relies on inorganic N species in the subtropical forest. This suggests that the fern employs different strategies to acquire available N which depends on N levels and time.

  8. Rates of molecular evolution in tree ferns are associated with body size, environmental temperature and biological productivity.

    Science.gov (United States)

    Barrera-Redondo, Josué; Ramirez-Barahona, Santiago; Eguiarte, Luis E

    2018-03-31

    Variation in rates of molecular evolution (heterotachy) is a common phenomenon among plants. Although multiple theoretical models have been proposed, fundamental questions remain regarding the combined effects of ecological and morphological traits on rate heterogeneity. Here, we used tree ferns to explore the correlation between rates of molecular evolution in chloroplast DNA sequences and several morphological and environmental factors within a Bayesian framework. We revealed direct and indirect effects of body size, biological productivity, and temperature on substitution rates, where smaller tree ferns living in warmer and less productive environments tend to have faster rates of molecular evolution. In addition, we found that variation in the ratio of non-synonymous to synonymous substitution rates (dN/dS) in the chloroplast rbcL gene was significantly correlated with ecological and morphological variables. Heterotachy in tree ferns may be influenced by effective population size associated with variation in body size and productivity. Macroevolutionary hypotheses should go beyond explaining heterotachy in terms of mutation rates and instead, should integrate population-level factors to better understand the processes affecting the tempo of evolution at the molecular level. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Identification and Characterization of TALE Homeobox Genes in the Endangered Fern Vandenboschia speciosa.

    Science.gov (United States)

    Ruiz-Estévez, Mercedes; Bakkali, Mohammed; Martín-Blázquez, Rubén; Garrido-Ramos, Manuel A

    2017-10-17

    We report and discuss the results of a quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis of the expression patterns of seven three amino acid loop extension ( TALE ) homeobox genes (four KNOTTED-like homeobox ( KNOX ) and three BEL1-like homeobox ( BELL ) genes) identified after next generation sequencing (NGS) and assembly of the sporophyte and gametophyte transcriptomes of the endangered fern species Vandenboschia speciosa . Among the four KNOX genes, two belonged to the KNOX1 class and the other two belonged to the KNOX2 class. Analysis of the deduced amino acid sequences supported the typical domain structure of both types of TALE proteins, and the homology to TALE proteins of mosses, lycophytes, and seed plant species. The expression analyses demonstrate that these homeodomain proteins appear to have a key role in the establishment and development of the gametophyte and sporophyte phases of V. speciosa lifecycle, as well as in the control of the transition between both phases. Vandenboschia speciosa VsKNAT3 (a KNOX2 class protein) as well as VsBELL4 and VsBELL10 proteins have higher expression levels during the sporophyte program. On the contrary, one V. speciosa KNOX1 protein (VsKNAT6) and one KNOX2 protein (VsKNAT4) seem important during the development of the gametophyte phase. TALE homeobox genes might be among the key regulators in the gametophyte-to-sporophyte developmental transition in regular populations that show alternation of generations, since some of the genes analyzed here ( VsKNAT3 , VsKNAT6 , VsBELL4 , and VsBELL6 ) are upregulated in a non-alternating population in which only independent gametophytes are found (they grow by vegetative reproduction outside of the range of sporophyte distribution). Thus, these four genes might trigger the vegetative propagation of the gametophyte and the repression of the sexual development in populations composed of independent gametophytes. This study represents a comprehensive

  10. Use of rbcL and trnL-F as a two-locus DNA barcode for identification of NW-European ferns: an ecological perspective.

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    G Arjen de Groot

    2011-01-01

    Full Text Available Although consensus has now been reached on a general two-locus DNA barcode for land plants, the selected combination of markers (rbcL + matK is not applicable for ferns at the moment. Yet especially for ferns, DNA barcoding is potentially of great value since fern gametophytes--while playing an essential role in fern colonization and reproduction--generally lack the morphological complexity for morphology-based identification and have therefore been underappreciated in ecological studies. We evaluated the potential of a combination of rbcL with a noncoding plastid marker, trnL-F, to obtain DNA-identifications for fern species. A regional approach was adopted, by creating a reference database of trusted rbcL and trnL-F sequences for the wild-occurring homosporous ferns of NW-Europe. A combination of parsimony analyses and distance-based analyses was performed to evaluate the discriminatory power of the two-region barcode. DNA was successfully extracted from 86 tiny fern gametophytes and was used as a test case for the performance of DNA-based identification. Primer universality proved high for both markers. Based on the combined rbcL + trnL-F dataset, all genera as well as all species with non-equal chloroplast genomes formed their own well supported monophyletic clade, indicating a high discriminatory power. Interspecific distances were larger than intraspecific distances for all tested taxa. Identification tests on gametophytes showed a comparable result. All test samples could be identified to genus level, species identification was well possible unless they belonged to a pair of Dryopteris species with completely identical chloroplast genomes. Our results suggest a high potential of the combined use of rbcL and trnL-F as a two-locus cpDNA barcode for identification of fern species. A regional approach may be preferred for ecological tests. We here offer such a ready-to-use barcoding approach for ferns, which opens the way for answering a

  11. Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

    International Nuclear Information System (INIS)

    Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

    2009-01-01

    Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

  12. Synthesizing research and education: Ecology and genetics of independent fern gametophytes and teaching science inquiry and content through simulations

    Science.gov (United States)

    Duffy, Aaron M.

    Two of the main areas of focus in university academics are research and education. The mission statements of Utah State University and the Department of Biology emphasize both areas, as do the requirements of funding agencies. I attempted to integrate research and education by using tools that I developed to support and inform my biological research projects to teach science. Ferns have a life cycle with alternating haploid and diploid life stages, both of which are free-living and potentially long-lived. The haploid gametophytes of some ferns reproduce asexually and may have different environmental requirements than the diploid sporophytes, so it is possible for populations of gametophytes to exist without sporophytes. This dissertation includes a description of surveys for Hymenophyllum wrightii, a fern with independent gametophytes in the Pacific Northwest, and improves our understanding of the range, distribution, and habitat requirements of these plants which were previously assumed to be rare. It also describes an attempt to explore the population genetics of gametophytes of Crepidomanes intricatum, a widespread fern in the Appalachian Mountains for which no sporophytes have ever been found. To help visualize evolutionary processes in independent gametophyte populations I developed the Virtual Population Genetics Simulator (VPGsim) to simulate populations of ferns in a 3-dimensional environment. This dissertation includes a description of VPGsim, a learning module using it to teach undergraduate genetics, and a study demonstrating its effectiveness at improving students' understanding of science content and confidence in their ability to perform science inquiry. That simulation tool led to a collaboration to find other ways to teach science with simulations, and to the development of a Virtual Plant Community simulator (VPCsim) for teaching middle school students about the effects of the environment and human impacts on living organisms. This dissertation

  13. Inter-and intraspecific variation in fern mating systems after long-distance colonization: the importance of selfing

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    de Groot G Arjen

    2012-01-01

    Full Text Available Abstract Background Previous studies on the reproductive biology of ferns showed that mating strategies vary among species, and that polyploid species often show higher capacity for self-fertilization than diploid species. However, the amount of intraspecific variation in mating strategy and selfing capacity has only been assessed for a few species. Yet, such variation may have important consequences during colonization, as the establishment of any selfing genotypes may be favoured after long-distance dispersal (an idea known as Baker's law. Results We examined intra-and interspecific variation in potential for self-fertilization among four rare fern species, of which two were diploids and two were tetraploids: Asplenium scolopendrium (2n, Asplenium trichomanes subsp. quadrivalens (4n, Polystichum setiferum (2n and Polystichum aculeatum (4n. Sporophyte production was tested at different levels of inbreeding, by culturing gametophytes in isolation, as well as in paired cultures with a genetically different gametophyte. We tested gametophytes derived from various genetically different sporophytes from populations in a recently planted forest colonized through long-distance dispersal (Kuinderbos, the Netherlands, as well as from older, less disjunct populations. Sporophyte production in isolation was high for Kuinderbos genotypes of all four species. Selfing capacity did not differ significantly between diploids and polyploids, nor between species in general. Rather selfing capacity differed between genotypes within species. Intraspecific variation in mating system was found in all four species. In two species one genotype from the Kuinderbos showed enhanced sporophyte production in paired cultures. For the other species, including a renowned out crosser, selfing capacity was consistently high. Conclusions Our results for four different species suggest that intraspecific variation in mating system may be common, at least among temperate calcicole

  14. Occurrence of brassinosteroids in non-flowering land plants, liverwort, moss, lycophyte and fern.

    Science.gov (United States)

    Yokota, Takao; Ohnishi, Toshiyuki; Shibata, Kyomi; Asahina, Masashi; Nomura, Takahito; Fujita, Tomomichi; Ishizaki, Kimitsune; Kohchi, Takayuki

    2017-04-01

    Endogenous brassinosteroids (BRs) in non-flowering land plants were analyzed. BRs were found in a liverwort (Marchantia polymorpha), a moss (Physcomitrella patens), lycophytes (Selaginella moellendorffii and S. uncinata) and 13 fern species. A biologically active BR, castasterone (CS), was identified in most of these non-flowering plants but another biologically active BR, brassinolide, was not. It may be distinctive that levels of CS in non-flowering plants were orders of magnitude lower than those in flowering plants. 22-Hydroxycampesterol and its metabolites were identified in most of the non-flowering plants suggesting that the biosynthesis of BRs via 22-hydroxylation of campesterol occurs as in flowering plants. Phylogenetic analyses indicated that M. polymorpha, P. patens and S. moellendorffii have cytochrome P450s in the CYP85 clans which harbors BR biosynthesis enzymes, although the P450 profiles are simpler as compared with Arabidopsis and rice. Furthermore, these basal land plants were found to have multiple P450s in the CYP72 clan which harbors enzymes to catabolize BRs. These findings indicate that green plants were able to synthesize and inactivate BRs from the land-transition stage. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Sporangium Exposure and Spore Release in the Peruvian Maidenhair Fern (Adiantum peruvianum, Pteridaceae.

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    Simon Poppinga

    Full Text Available We investigated the different processes involved in spore liberation in the polypod fern Adiantum peruvianum (Pteridaceae. Sporangia are being produced on the undersides of so-called false indusia, which are situated at the abaxial surface of the pinnule margins, and become exposed by a desiccation-induced movement of these pinnule flaps. The complex folding kinematics and functional morphology of false indusia are being described, and we discuss scenarios of movement initiation and passive hydraulic actuation of these structures. High-speed cinematography allowed for analyses of fast sporangium motion and for tracking ejected spores. Separation and liberation of spores from the sporangia are induced by relaxation of the annulus (the 'throwing arm' of the sporangium catapult and conservation of momentum generated during this process, which leads to sporangium bouncing. The ultra-lightweight spores travel through air with a maximum velocity of ~5 m s(-1, and a launch acceleration of ~6300 g is measured. In some cases, the whole sporangium, or parts of it, together with contained spores break away from the false indusium and are shed as a whole. Also, spores can stick together and form spore clumps. Both findings are discussed in the context of wind dispersal.

  16. Interdisciplinary study of the panel painting depicting the "Pentecostes", attributed to Fernão Gomes

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    Diana Conde

    2010-01-01

    Full Text Available This paper presents a study on the technique and materials used in the panel painting entitled Pentecostes, attributed to the artist Fernão Gomes (XVIIth century, housed in the Museu Nacional de Arte Antiga, in Lisbon. The study also includes the diagnosis of the conservation state of the painting and the description of the cleaning intervention. For identification of the materials and determination of the conservation state, several analytical techniques were used: micro-FTIR and GC-MS, for identification of the binder and varnish; micro-Raman and micro-FTIR, for identification of fillers and pigments; micro-XRF and SEM-EDX, for elemental analysis; optical microscopy, with visible and fluorescent radiation, and infrared photography, for morphological observation and study of pictorial technique. The analytical approach led to the identification of materials common at the time: gypsum with animal glue, lead white, yellow and red ochres, black earths (based on Mn, Bi, Fe, azurite, possible green earth, lead red, oil and oily varnish with residues of cholesterol. After various cleaning tests, a gel suggested by the literature was chosen (recipe no. 105.4 developed by R. Wolbers and proved to be effective in the removal of the aged and polymerized varnish.

  17. Expression of an insecticidal fern protein in cotton protects against whitefly.

    Science.gov (United States)

    Shukla, Anoop Kumar; Upadhyay, Santosh Kumar; Mishra, Manisha; Saurabh, Sharad; Singh, Rahul; Singh, Harpal; Thakur, Nidhi; Rai, Preeti; Pandey, Paras; Hans, Aradhana L; Srivastava, Subhi; Rajapure, Vikram; Yadav, Sunil Kumar; Singh, Mithlesh Kumar; Kumar, Jitendra; Chandrashekar, K; Verma, Praveen C; Singh, Ajit Pratap; Nair, K N; Bhadauria, Smrati; Wahajuddin, Muhammad; Singh, Sarika; Sharma, Sharad; Omkar; Upadhyay, Ram Sanmukh; Ranade, Shirish A; Tuli, Rakesh; Singh, Pradhyumna Kumar

    2016-10-01

    Whitefly (Bemisia tabaci) damages field crops by sucking sap and transmitting viral diseases. None of the insecticidal proteins used in genetically modified (GM) crop plants to date are effective against whitefly. We report the identification of a protein (Tma12) from an edible fern, Tectaria macrodonta (Fee) C. Chr., that is insecticidal to whitefly (median lethal concentration = 1.49 μg/ml in in vitro feeding assays) and interferes with its life cycle at sublethal doses. Transgenic cotton lines that express Tma12 at ∼0.01% of total soluble leaf protein were resistant to whitefly infestation in contained field trials, with no detectable yield penalty. The transgenic cotton lines were also protected from whitefly-borne cotton leaf curl viral disease. Rats fed Tma12 showed no detectable histological or biochemical changes, and this, together with the predicted absence of allergenic domains in Tma12, indicates that Tma12 might be well suited for deployment in GM crops to control whitefly and the viruses it carries.

  18. Biometry of stomata in Blechnum species (Blechnaceae with some taxonomic and ecological implications for the ferns

    Directory of Open Access Journals (Sweden)

    José María Gabriel y Galán

    2011-03-01

    Full Text Available Morphological stomatal traits, such as size, form and frequency, have been subject of much literature, including their relationships with environmental factors. However, little effort have focused on ferns, and very few in the genus Blechnum. Stomatal length, width and frequency (as stomatal index of a number of specimens of fourteen Neotropical species of Blechnum were measured in adult pinnae. The aim of the work was to find biometrical relationships between stomatal traits and between stomatal traits and habit, habitat and ecosystem of the plants. Statistical analyses of data were conducted using Exploratory Data Analysis and Multivariate Statistical Methods. Stomatal length and width showed a very high correlation, suggesting an endogenous, genetic control, thus giving these traits a considerable diagnostic utility. With respect to the relationships between stomatal traits and environment, we found significant statistical relationships between altitude and stomatal index. We also addressed the interpretation of the ecological- selective significance of various assemblages of stomatal traits in a diverse conjunction of habits, habitats and ecosystems. Rev. Biol. Trop. 59 (1: 403-415. Epub 2011 March 01.

  19. Carcinogenicity of tannin and tannin-free extracts of bracken fern (Pteridium aquilinum) in rats.

    Science.gov (United States)

    Pamukcu, A M; Wang, C Y; Hatcher, J; Bryan, G T

    1980-07-01

    F344 inbred and Sprague-Dawley noninbred rats were fed a basic diet (groups 1 and 7) or a basic diet supplemented with 0.1% (later, 0.2 and 0.4%) tannin (group 2) isolated from bracken fern (Pteridium aquilinum) (BF), 33% BF (groups 3 and 6), 2% chloroform fraction of BF (group 4), or 4% tannin-free fraction of BF (group 5). The following incidences of intestinal or bladder tumors were observed: group 1, intestinal and bladder, 0/16; group 2, 0/21; group 7, 0/16; groups 4 and 5, intestinal, 7/15, bladder, 0/15; group 3, intestinal, 19/20, bladder, 12/20; and group 6, intestinal, 22/30, bladder, 15/30. The chloroform-methanol fraction prepared from urine of rats fed BF, chloroform fraction of BF, or tannin-free fraction of BF demonstrated mutagenicity for Salmonella typhimurium TA 100 but not for TA 98. No mutagenicity was detected in other prepared fractions. F344 rats in group 8 received weekly sc injections of tannin solution (0.1 g/kg body wt) for 38 weeks, and 16/20 developed palpable tumors that were malignant fibrous histiocytomas at the injection site. No tumor was present in any rat of control group 9.

  20. Cytomixis with associated chromosomal anomalies and the reproduction of Chlorophytum borivilianum Santapau & R. R. Fern.

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    Gopal Dev Mandal

    2017-05-01

    Full Text Available Cytomixis, a phenomenon of mixing up of cell contents of adjacent cells, though unusual in nature, have been witnessed in plenty of angiospermous plants. In addition, coexistence of some other irregularities in chromosomal behavior has also been noted in many a case to violate the normal process of meiosis. In this paper an account of the occurrence of cytomixis in the pollen mother as well as tapetal cells of Chlorophytum borivilianum Santapau & R. R. Fern. has been presented for the first time. A variety of chromosomal abnormalities has been recorded too. The species, mainly known for aphrodisiac properties, also provides biochemicals of curative properties against many ailments. The herb reproduces mostly by vegetative means and seed germination is meager. The nature and extent of cytomixis associated anomalies seem to provide a plausible cue in understanding the occurrence of only vegetative means of reproduction. Cytomixis of an accrued amount of 4.21 % occurs with greater preponderance only in meiosis I; while, chromosomal abnormalities, altogether of 21.16 %, are recorded in different stages of both of meiosis I and II. In PMCs the varieties of unusual features recorded are chromatin transfer to adjacent cell, chromosome stickiness, loss of chromosomes, improper orientation of chromatin/chromosomes, chromosome bridges and formation of micronuclei at different stages. A considerable extent (27.20 % of pollens has been noted to be sterile.

  1. Ontogeny and ecology of the filicalean fern Oligocarpia gothanii (Gleicheniaceae) from the Middle Permian of China.

    Science.gov (United States)

    Stevens, Liadan G; Hilton, Jason

    2009-02-01

    Reinvestigation of Oligocarpia gothanii Halle (Gleicheniaceae) from the Permian Period of China has uncovered a rare demonstration of ontogenetic succession in numerous intact plants and has led to emendation of the diagnosis and typification of the species. Reconstruction of the fern's vegetative life cycle shows a small rosette-shaped juvenile plant with immature fronds of pinnae undifferentiated into pinnules. The second stage is a series of leafy shoots increasing in size and complexity and bearing fronds essentially comparable with those of the adult plants. Mature plants have sphenopteroid-type fronds differentiated into vegetative and fertile fronds. Close association of plants on the same bedding plane and the presence of a connecting root network between shoots, show that juvenile plants spread by vegetative propagation using underground stolons. Sedimentological information and co-occurrence with the bryophyte Thallites hallei Lundblad suggests that O. gothanii occupied a wetland habitat and was preserved in an obrution event consistent with flooding of marginal areas in a fluvio-deltaic setting. Although recent studies on Oligocarpia have focused exclusively on reproductive features, new ontogenetic information suggests that plants growing in rapidly changing environments may have been reliant on vegetative propagation and would not have needed to reach sexual maturity for successful reproduction.

  2. Seed ferns from the late Paleozoic and Mesozoic: Any angiosperm ancestors lurking there?

    Science.gov (United States)

    Taylor, Edith L; Taylor, Thomas N

    2009-01-01

    Five orders of late Paleozoic-Mesozoic seed ferns have, at one time or another, figured in discussions on the origin of angiosperms, even before the application of phylogenetic systematics. These are the Glossopteridales, Peltaspermales, Corystospermales, Caytoniales, and Petriellales. Although vegetative features have been used to suggest homologies, most discussion has focused on ovulate structures, which are generally interpreted as megasporophylls bearing seeds, with the seeds partially to almost completely enclosed by the megasporophyll (or cupule). Here we discuss current information about the reproductive parts of these plants. Since most specimens are impression-compression remains, homologizing the ovulate organs, deriving angiospermous homologues, and defining synapomorphies remain somewhat speculative. Although new specimens have increased the known diversity in these groups, a reconstruction of an entire plant is available only for the corystosperms, and thus hypotheses about phylogenetic position are of limited value. We conclude that, in the case of these seed plants, phylogenetic analysis techniques have surpassed the hard data needed to formulate meaningful phylogenetic hypotheses. Speculation on angiosperm origins and transitional stages in these fossils provides for interesting discussion, but currently it is still speculation, as the role of these groups in the origin of angiospermy continues to be cloaked in Darwin's mystery.

  3. Arbuscular mycorrhiza formation in cordate gametophytes of two ferns, Angiopteris lygodiifolia and Osmunda japonica.

    Science.gov (United States)

    Ogura-Tsujita, Yuki; Sakoda, Aki; Ebihara, Atsushi; Yukawa, Tomohisa; Imaichi, Ryoko

    2013-01-01

    Mycorrhizal symbiosis is common among land plants including pteridophytes (monilophytes and lycophytes). In pteridophytes with diplohaplontic life cycle, mycorrhizal formations were mostly reported for sporophytes, but very few for gametophytes. To clarify the mycorrhizal association of photosynthetic gametophytes, field-collected gametophytes of Angiopteris lygodiifolia (Marattiaceae, n = 52) and Osmunda japonica (Osmundaceae, n = 45) were examined using microscopic and molecular techniques. Collected gametophytes were mostly cut into two pieces. One piece was used for light and scanning microscopic observations, and the other for molecular identification of plant species (chloroplast rbcL sequences) and mycorrhizal fungi (small subunit rDNA sequences). Microscopic observations showed that 96 % (50/52) of Angiopteris and 95 % (41/43) of Osmunda gametophytes contained intracellular hyphae with arbuscules and/or vesicles and fungal colonization was limited to the inner tissue of the thick midribs (cushion). Fungal DNA analyses showed that 92 % (48/52) of Angiopteris and 92 % (35/38) of Osmunda have sequences of arbuscular mycorrhizal fungi, which were highly divergent but all belonged to Glomus group A. These results suggest that A. lygodiifolia and O. japonica gametophytes consistently form arbuscular mycorrhizae. Mycorrhizal formation in wild fern gametophytes, based on large-scale sampling with molecular identification of host plant species, was demonstrated for the first time.

  4. The potential of the fresh-water fern Azolla in aquatic farming systems

    Science.gov (United States)

    Bijl, Peter K.; Werf, vd, Adrie; Schluepmann, Henriette; Reichart, Gert-Jan; Brouwer, Paul; Nierop, Klaas G. J.; Hellgardt, Klaus; Brinkhuis, Henk

    2014-05-01

    With aquatic farming systems a new avenue in agriculture is explored, in which the competition with conventional arable land is avoided. The aquatic, ubiquitous, floating fern Azolla is not yet widely explored as potential crop in such farming systems, despite its high potential because it grows in many natural systems under low-light intensities, has an enormous annual yield, and has special biomass qualities for applications in food, feed and specialty chemical industries. But, what makes Azolla particularly interesting as cost-effective crop is its capability to take up atmospheric nitrogen through symbiosis with nitrogen-fixing bacteria Anabaena azollae. This makes Azolla independent of nitrogen fertilization. In order to explore the potential of Azolla as a crop for a suite of applications, we have assembled a team of expertise: AZOFAST, consisting of agricultural engineers, plant physiologists, chemical engineers and organic chemists. Our growth experiments reveal high annual production yields with constant harvest. We are developing a germination and spore collecting/preservation protocol as a first step to domestication. Finally we have explored the biomass quality of different species of extant Azolla. We performed organic chemical analyses on lipid and tannin extracts, and quantified yields of specific compounds within these fractions. In our presentation we will present some of our results to show the potential of Azolla as a new, sustainable aquatic crop serving all kinds of industrial streams from protein feed to platform chemicals.

  5. Arundina graminifolia var. revoluta (Arethuseae, Orchidaceae) has fern-type rheophyte characteristics in the leaves.

    Science.gov (United States)

    Yorifuji, Eri; Ishikawa, Naoko; Okada, Hiroshi; Tsukaya, Hirokazu

    2015-03-01

    Morphological and molecular variation between Arundina graminifolia var. graminifolia and the dwarf variety, A. graminifolia var. revoluta, was examined to assess the validity of their taxonomic characteristics and genetic background for identification. Morphological analysis in combination with field observations indicated that A. graminifolia var. revoluta is a rheophyte form of A. graminifolia characterized by narrow leaves, whereas the other morphological characteristics described for A. graminifolia var. revoluta, such as smaller flowers and short stems, were not always accompanied by the narrower leaf phenotype. Molecular analysis based on matK sequences indicated that only partial differentiation has occurred between A. graminifolia var. graminifolia and A. graminifolia var. revoluta. Therefore, we should consider the rheophyte form an ecotype rather than a variety. Anatomical observations of the leaves revealed that the rheophyte form of A. graminifolia possessed characteristics of the rheophytes of both ferns and angiosperms, such as narrower palisade tissue cells and thinner spongy tissue cells, as well as fewer cells in the leaf-width direction and fewer mesophyll cell layers.

  6. Geometry, Allometry and Biomechanics of Fern Leaf Petioles: Their Significance for the Evolution of Functional and Ecological Diversity Within the Pteridaceae

    Directory of Open Access Journals (Sweden)

    Jennifer N. Mahley

    2018-03-01

    Full Text Available Herbaceous plants rely on a combination of turgor, ground tissues and geometry for mechanical support of leaves and stems. Unlike most angiosperms however, ferns employ a sub-dermal layer of fibers, known as a hypodermal sterome, for support of their leaves. The sterome is nearly ubiquitous in ferns, but nothing is known about its role in leaf biomechanics. The goal of this research was to characterize sterome attributes in ferns that experience a broad range of mechanical stresses, as imposed by their aquatic, xeric, epiphytic, and terrestrial niches. Members of the Pteridaceae meet this criteria well. The anatomical and functional morphometrics along with published values of tissue moduli were used to model petiole flexural rigidity and susceptibility to buckling in 20 species of the Pteridaceae. Strong allometric relationships were observed between sterome thickness and leaf size, with the sterome contributing over 97% to petiole flexural rigidity. Surprisingly, the small-statured cheilanthoid ferns allocated the highest fraction of their petiole to the sterome, while large leaves exploited aspects of geometry (second moment of area to achieve bending resistance. This pattern also revealed an economy of function in which increasing sterome thickness was associated with decreasing fiber cell reinforcement, and fiber wall fraction. Lastly, strong petioles were associated with durable leaves, as approximated by specific leaf area. This study reveals meaningful patterns in fern leaf biomechanics that align with species leaf size, sterome attributes and life-history strategy.

  7. Intrathermocline eddies at the Juan Fernández Archipelago, southeastern Pacific

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2014-10-01

    Full Text Available Regional Ocean Modeling System (ROMS results, combined with chlorophyll-α (Chl-α and satellite altimetry information as well as information from oceanographic cruises were analyzed to identify interactions between intrathermocline eddies (ITEs and the Juan Fernández Archipelago (JFA, and discuss their potential impact on surface Chl-α concentrations. The JFA is located off the coast of central Chile (33°S, and is composed of three main islands: Robinson Crusoe (RC, Alejandro Selkirk (AS and Santa Clara (SC. Results indicate that the surface and subsurface anticyclonic eddies that interact with the JFA are formed primarily within the coastal transition zone between 33° and 39°S. ITEs are present within the JFA region with a semiannual frequency, mainly during the austral autumn, and have a weak surface expression in relation to the adjacent surface eddies, with a slow displacement (1.16 to 1.4 km d-1 in a northwest direction and a coherent structure for periods of ≥ 1 year. During the ITEs' interaction with RC-SC islands and an adjacent seamount, a slight (prominent thermocline deflection of the upper limit (lower was observed. The horizontal extent (~70-100 km was greater than the internal Rossby deformation radius and the average vertical extent was ~400 m. The interaction between the weak surface expression of ITEs, identified with satellite altimetry, and the JFA persisted during autumn for nine weeks until reaching the winter period. Approximately one month after the beginning of the interaction between ITEs and the islands, increases in surface Chl-α associated with the eddy were observed, with values up to three times higher than adjacent oceanic waters.

  8. The potential of the aquatic water fern Azolla within a biobased economy

    Science.gov (United States)

    Nierop, Klaas G. J.; Jongerius, Anna L.; Bijl, Peter K.; Bruijnincx, Pieter C. A.; Klein Gebbink, Robertus J. M.; Reichart, Gert-Jan

    2014-05-01

    Azolla is a free-floating freshwater fern capable of fixing atmospheric carbon dioxide and nitrogen, the latter of which through its symbiosis with the cyanobacteria Anabaena azollae. It is currently ranked among the fastest growing plants on Earth and occurs in both tropical and temperate freshwater ecosystems. Therefore, it is non-directly competitive with food crops. In addition, Azolla does not require inorganic fertilizers, which makes it a potential and unique source of biomass for the sustainable production of fuels and chemicals that are currently derived from fossil (fuel) sources. The biochemical composition of Azolla allows the production of biofuel or biobased chemicals that are of interest to the chemical industry. Of Azolla, two extractable groups of compounds are of particular interest, i.e. the polyphenols (condensed tannins and ester-bound caffeic acid) and the lipids. The antioxidant property of polyphenols and their application to the treatment of cancer, diabetes and cardiovascular diseases has further contributed to the growth of the polyphenol market. In addition, they can be chemically transformed into aromatic platform and specialty chemicals. The composition of the lipid fraction of Azolla is characterized by highly specific compounds consisting of C26-C36 carbon chains all bearing a ω20-hydroxy group. Such compounds produce an oil fraction upon hydrous pyrolysis, or, alternatively, are well suited to be converted to e.g. various specialty chemicals that are hardly available from both natural sources. Indeed, upon chemical conversion these lipids may yield components for fuels, plastics, cosmetics, and lubricants. Another group of interesting compounds within the lipid group are the polyunsaturated fatty acids (PUFAs). The demand for PUFAs has witnessed a significant increase over the last three years, particularly due to their benefits as cholesterol lowering agents. Here we will present some of the thermal and chemical conversions of the

  9. Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia, B1P 6L2 (Canada); D' Angelo, Jose A. [IANIGLA, CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, Bloomington, IN, 47405-2208 (United States); Cleal, Christopher J. [Department of Biodiversity and Systematic Biology, National Museum of Wales, Cathays Park, Cardiff, CF10 3NP (United Kingdom); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

    2010-11-01

    In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond. Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season. This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. (author)

  10. La colección Fernández Rivero de fotografía antigua

    Directory of Open Access Journals (Sweden)

    García Ballesteros, María Teresa

    2015-02-01

    Full Text Available La Colección Fernández Rivero de fotografía antigua es una colección de objetos fotográficos originales de más de 45000 piezas de diversa tipología. La CFRivero ha seguido para su formación un criterio historicista de manera que pudiese cubrir fines museísticos y didácticos. Alrededor de dos tercios de sus piezas son del siglo XIX, de las cuales la mayor parte podrían describirse como parte fundamental del patrimonio fotográfico español de este periodo. Es por tanto una colección fundamentalmente de fotografía histórica española, aunque contiene también notables ejemplos representativos de fotografía de Francia, Reino Unido y otros países, además de dos secciones especiales: fotografía estereoscópica y fotografía relacionada con Málaga y su provincia. Se complementa con máquinas y otros objetos fotográficos así como con una nutrida biblioteca antigua y contemporánea. Los propietarios vienen desarrollando una amplia labor de difusión e investigación del fenómeno fotográfico, centrado especialmente en el siglo XIX. Para ello se han publicado libros y artículos, celebrado exposiciones, conferencias y talleres, así como una amplia y activa difusión a través de Internet.

  11. In vitro assessment of anticholinesterase and NADH oxidase inhibitory activities of an edible fern, Diplazium esculentum.

    Science.gov (United States)

    Roy, Subhrajyoti; Dutta, Somit; Chaudhuri, Tapas Kumar

    2015-07-01

    Diplazium esculentum is the most commonly consumed edible fern throughout Asia and Oceania. Several studies have been performed so far to determine different functional properties of this plant, but there have been no reports on the anticholinesterase and nicotinamide adenine dinucleotide (NADH) oxidase inhibitory activities of this plant. Therefore, the present study was conducted to determine the anticholinesterase and NADH oxidase inhibitory activities of 70% methanolic extract of D. esculentum. The D. esculentum extract was investigated for its acetylcholinesterase and NADH oxidase inhibitory activities as well as its free radical scavenging and total antioxidant activities in the linoleic acid system. The free radical scavenging activity of the extract was determined by the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) method. The total antioxidant activity of the extract was evaluated by ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. The D. esculentum extract inhibited acetylcholinesterase and NADH oxidase in a dose-dependent manner, with IC50 values of 272.97±19.38 and 265.81±21.20 μg/mL, respectively. The extract also showed a potent DPPH radical scavenging activity with an IC50 value of 402.88±12.70 μg/mL. Moreover, the extract showed 27.41% and 33.22% of total antioxidant activities determined by FTC and TBA methods, respectively. Results indicated that 70% methanolic extract of D. esculentum effectively inhibited the enzymes acetylcholinesterase and NADH oxidase and acted as a potent antioxidant and free radical scavenger. These in vitro assays indicate that this plant extract is a significant source of natural antioxidants, which may be helpful in preventing the progression of various neurodegenerative disorders associated with oxidative stress.

  12. Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

    Science.gov (United States)

    Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Cleal, C.J.; Keefe, D.

    2010-01-01

    In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond.Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season.This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. ?? 2010 Elsevier B.V.

  13. Understanding mechanisms of rarity in pteridophytes: competition and climate change threaten the rare fern Asplenium scolopendrium var. americanum (Aspleniaceae).

    Science.gov (United States)

    Testo, Weston L; Watkins, James E

    2013-11-01

    Understanding the ecology of rare species can inform aspects of conservation strategies; however, the mechanisms of rarity remain elusive for most pteridophytes, which possess independent and ecologically distinct gametophyte and sporophyte generations. To elucidate factors contributing to recent declines of the rare fern Asplenium scolopendrium var. americanum, we studied the ecology and ecophysiology of its gametophyte generation, focusing on responses to competition, temperature, and water stress. Gametophytes of A. scolopendrium var. americanum, its widespread European relative A. scolopendrium var. scolopendrium, and five co-occurring fern species were grown from spores. Gametophytes were grown at 20°C and 25°C, and germination rates, intra- and interspecific competition, desiccation tolerance, and sporophyte production were determined for all species. Gametophytes of A. scolopendrium var. americanum had the lowest rates of germination and sporophyte production among all species studied and exhibited the greatest sensitivity to interspecific competition, temperature increases, and desiccation. Mature gametophytes of A. scolopendrium var. americanum grown at 25°C were 84.6% smaller than those grown at 20°C, and only 1.5% produced sporophytes after 200 d in culture. Similar responses were not observed in other species studied. The recent declines and current status of populations of A. scolopendrium var. americanum are linked to its gametophyte's limited capacity to tolerate competition and physiological stress linked to climate change. This is the first study to develop a mechanistic understanding of rarity and decline in a fern and demonstrates the importance of considering the ecology of the gametophyte in plants with independent sporophyte and gametophyte generations.

  14. Figurations of Islandness in Argentine Culture and Literature: Macedonio Fernández, Leopoldo Marechal, and César Aira

    Directory of Open Access Journals (Sweden)

    Norman Cheadle

    2009-11-01

    Full Text Available This article explores islandness in the River Plate imaginary. Two modern foundational “island texts” – Thomas More’s Utopia and Daniel Defoe’s Robinson Crusoe – have exerted a formative influence on the Spanish-American colonial imagination, an influence inflected by the particular historical experience of the River Plate region and its dominant city, Buenos Aires. The figuration of islandness is examined in three twentieth-century Argentine novels by Macedonio Fernández, Leopoldo Marechal, and César Aira. The article finds both continuity and evolution in the images of islandness in these novels.

  15. Ptaquiloside Z, a new toxic unstable sesquiterpene glucoside from the neotropical bracken fern Pteridium aquilinum var. caudatum.

    Science.gov (United States)

    Castillo, U F; Ojika, M; Alonso-Amelot, M; Sakagami, Y

    1998-11-01

    Reversed-phase HPLC fractionation, monitored by brine shrimp bioassay, led to the isolation of a new illudane-type sesquiterpene glucoside, ptaquiloside Z (2), as well as the known bracken carcinogen ptaquiloside (1), from a bioactive aqueous extract of the neotropical bracken fern Pteridium aquilinum var. caudatum (Pteridaceae). The structure of ptaquiloside Z (2) was confirmed by spectroscopic analyses and chemical degradation. Both compounds exhibited similar toxicity (LC50 62.5 micrograms/ml at 24 h and LC50 7.8 micrograms/ml at 48 h) toward brine shrimp.

  16. Developing and Deploying an XML-based Learning Content Management System at the FernUniversität Hagen

    Directory of Open Access Journals (Sweden)

    Gerd Steinkamp

    2005-02-01

    Full Text Available This paper is a report about the FuXML project carried out at the FernUniversität Hagen. FuXML is a Learning Content Management System (LCMS aimed at providing a practical and efficient solution for the issues attributed to authoring, maintenance, production and distribution of online and offline distance learning material. The paper presents the environment for which the system was conceived and describes the technical realisation. We discuss the reasons for specific implementation decisions and also address the integration of the system within the organisational and technical infrastructure of the university.

  17. 15 June 2009 - President of the Argentine Nation C. Fernández visiting ATLAS experimental area.

    CERN Multimedia

    Maximilien Brice

    2009-01-01

    Tirage 1:President of the Argentine Nation, C. Fernández and Minister of Science, Technology and Innovative Production,L. Barañao Tirage 2-8:Arrival greetings Tirage 9-12:Introduction to CERN's activities by Director-General, R. Heuer Tirage 13-15:Signature of the guest book Tirage 16-25:M. Benedetti,R. Heuer and L.Barañao sit for the signature of the Agreement Tirage 26-33: Meeting with Argentinian scientists at CERN

  18. Explotación de peces asociada a la pesquería artesanal de langosta de Juan Fernández (Jasus frontalis

    Directory of Open Access Journals (Sweden)

    Mauricio Ahumada

    2014-03-01

    Full Text Available Para contribuir al conocimiento de la explotación de peces asociada a la pesquería de langosta de Juan Fernández, se monitorearon 157 salidas de pesca durante la temporada 2010-2011. Se capturaron 10.462 ejemplares correspondientes a 19 especies de peces, tres de las cuales concentraron el 94% de la captura en número: jurel de Juan Fernández (Pseudocaranx chilensis (45%, breca (Nemadactylus gayi (41% y anguila morena (Gymnothoraxporphyreus (8%. Las capturas totales estimadas fueron 40, 24 y 13 ton de breca, jurel de Juan Fernández y anguila morena, respectivamente. El 97% de los ejemplares de peces capturados fueron utilizados como carnada de peces o langosta.

  19. Antibody-based screening of cell wall matrix glycans in ferns reveals taxon, tissue and cell-type specific distribution patterns

    DEFF Research Database (Denmark)

    Leroux, Olivier; Sørensen, Iben; Marcus, Susan E.

    2015-01-01

    Background: While it is kno3wn that complex tissues with specialized functions emerged during land plant evolution, it is not clear how cell wall polymers and their structural variants are associated with specific tissues or cell types. Moreover, due to the economic importance of many flowering...... epitopes display complex spatio-temporal and phylogenetic distribution patterns that are likely to relate to the evolution of land plant body plans....... plants, ferns have been largely neglected in cell wall comparative studies. Results: To explore fern cell wall diversity sets of monoclonal antibodies directed to matrix glycans of angiosperm cell walls have been used in glycan microarray and in situ analyses with 76 fern species and four species...

  20. A comparative analysis of ontomorphogenesis of the gametophytes of two epilithic ferns Asplenium adiantum-nigrum and Adiantum capillus-veneris L.

    Directory of Open Access Journals (Sweden)

    Zoya M. Ivaschenko

    2014-04-01

    Full Text Available A comparative study of ontomorphogenesis and polyvariance of two epilithic ferns gametophytes Asplenium adiantum-nigrum and Adiantum capillus-veneris is carried out. The spores of two species significantly differ in their structure. The germination of spores of two species goes on Vittaria-type. The development of prothallium goes on two different types. The investigated ferns also showed significant morphological diversity of gametophytes forms. The differences are found also and in the location of gametangiums on prothallus, and in the rates of sexualization. At the studied species vegetative reproduction by means of proliferation is noted. The following types of ontogenesis are tracked: full and reduced functionally finished ontogenesis with reproduction of diplophase (sporophytes, and also full and reduced functionally not finished ontogenesis. The structural and dynamic polyvariance of gametophytes ontogenesis of two species of ferns is found out.

  1. Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

    Science.gov (United States)

    Zodrow, E.L.; Mastalerz, Maria

    2001-01-01

    Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH2/CH3 ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed. ?? 2001 Elsevier Science B.V. All rights reserved.

  2. Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, PO Box 5300, Nova Scotia, B1P 6L2 Sydney (Canada); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, 47405-2208 Bloomington, IN (United States)

    2001-07-01

    Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH{sub 2}/CH{sub 3} ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed.

  3. “Barba Azul”: de Perrault a Wenceslao Fernández Flórez / “Bluebeard”: from Perrault to Wenceslao Fernández Flórez

    Directory of Open Access Journals (Sweden)

    Fermín Ezpeleta Aguilar

    2012-01-01

    Full Text Available Resumen: En este artículo se pone de manifiesto la amalgama de datos de historia real y de elementos míticos con los que se conforma literariamente el motivo literario de Barba Azul a lo largo del tiempo. Se deslindan, sobre todo, las dos versiones más importantes que hacen del motivo un cuento popular: la de Perrault y la de los hermanos Grimm, para analizar a continuación la reescritura que hace Wenceslao Fernández Flórez en su narración El secreto de Barba Azul (1923. Esta novela de formación tan representativa del autor se pone en conexión con el resto de su producción literaria y se comentan en ella aquellos aspectos temáticos y estructurales que inciden en la cuestión educativa, señalando intertextualidades con las versiones del cuento popular.Abstract: This article shows the historical data of real and mythical elements about Bluebeard motif over time. We identify in particular the two most important versions which make the topic a folktale: Perrault and Grimm Brothers, to discuss then the rewriting by Wenceslao Fernández Flórez, El secreto de Barba Azul (1923. This Bildungsroman connects strongly with the rest of his literature. We comment on the thematic and structural aspects that are closely related to education, noting intertextualities with versions of the folktale.

  4. Hasta siempre Profesor Manuel Fernández: Palabras en homenaje al ex Decano de la Facultad de Arquitectura y Urbanismo Dr. Arqto. Manuel Fernández Hechenleitner (1946- 2003. / Farewell, Professor Manuel Fernandez: Words in tribute to the former - Dean of the Faculty of Architecture and Planning Dr. Arqto. Manuel Fernández Hechenleitner (1946 - 2003.

    Directory of Open Access Journals (Sweden)

    Javier de Cárdenas

    2003-06-01

    Full Text Available Académicos, ex alumnos y amigos de la Facultad de Arquitectura y Urbanismo de la Universidad de Chile, recuerdan la personalidad del Dr. Arquitecto Manuel Fernández Hechenleitner (1946-2003, ex Decano de la F.A.U., con motivo de su fallecimiento./Academics, ex - students and friends of the School of Architecture and Urbanism of the University of Chile, remember the personality of Dr. Manuel Fernandez Hechenleitner Architect (1946-2003, ex - Dean of the FAU, on the occasion of his death.

  5. Acrostichum, a Pioneering Fern of Floodplain Areas from the Late Oligocene Sariñena Formation of the Iberian Peninsula

    Science.gov (United States)

    Ferrer, Javier; Diez, José B.

    2016-01-01

    Acrostichum is considered today an opportunistic fern in disturbed areas, which indicates the first stages of colonisation of such zones. However, in the fossil record, Acrostichum appears related to fluvio-lacustrine environments, freshwater marshes and mangrove deposits. We report here for first time fossil evidence of Acrostichum that reveals a pioneering behaviour of this fern in the colonisation of perturbed communities in Europe, which corroborates previous assumptions about the paleobiology of Acrostichum. Plant remains were collected from the Chattian (late Oligocene) La Val fossil site (Estadilla, Huesca, northeastern Spain) belonging to the Sariñena Formation, which mainly embraces crevasse splays, levees and floodplain deposits. Evidence shows that Acrostichum grew within the levee’s vegetal community or close to/on the river banks as well as on floodplain areas and closer to/on the shores of ephemeral ponds. But most importantly, the observed co-existence of Equisetum and Acrostichum remains in the same beds indicates that such strata represent short-lived inundated terrains, e.g., floodplains where the water table was temporarily stagnant. Evidence shows wetland environments dominated by pioneering taxa, implying a pioneering role for Acrostichum during the late Oligocene in the Iberian Peninsula. PMID:27631099

  6. Comparison between WorldView-2 and SPOT-5 images in mapping the bracken fern using the random forest algorithm

    Science.gov (United States)

    Odindi, John; Adam, Elhadi; Ngubane, Zinhle; Mutanga, Onisimo; Slotow, Rob

    2014-01-01

    Plant species invasion is known to be a major threat to socioeconomic and ecological systems. Due to high cost and limited extents of urban green spaces, high mapping accuracy is necessary to optimize the management of such spaces. We compare the performance of the new-generation WorldView-2 (WV-2) and SPOT-5 images in mapping the bracken fern [Pteridium aquilinum (L) kuhn] in a conserved urban landscape. Using the random forest algorithm, grid-search approaches based on out-of-bag estimate error were used to determine the optimal ntree and mtry combinations. The variable importance and backward feature elimination techniques were further used to determine the influence of the image bands on mapping accuracy. Additionally, the value of the commonly used vegetation indices in enhancing the classification accuracy was tested on the better performing image data. Results show that the performance of the new WV-2 bands was better than that of the traditional bands. Overall classification accuracies of 84.72 and 72.22% were achieved for the WV-2 and SPOT images, respectively. Use of selected indices from the WV-2 bands increased the overall classification accuracy to 91.67%. The findings in this study show the suitability of the new generation in mapping the bracken fern within the often vulnerable urban natural vegetation cover types.

  7. Morphological factors as indicators of malignancy of squamous cell carcinomas in cattle exposed naturally to bracken fern (Pteridium aquilinum).

    Science.gov (United States)

    Masuda, E K; Kommers, G D; Martins, T B; Barros, C S L; Piazer, J V M

    2011-01-01

    Squamous cell carcinomas (SCCs) of the upper digestive tract (UDT) of cattle have been associated with chronic bracken fern (Pteridium aquilinum) toxicity and infection with bovine papillomavirus type-4. These tumours share some morphological similarities with human head and neck SCCs. In this study, morphological changes were correlated with the biological behaviour of 40 alimentary SCCs in cattle grazing on pastures with high bracken content. The majority of SCCs were localized to the cranial and caudal regions of the UDT (almost 45% each). More than 60% of the tumours were well differentiated and were found mostly in the cranial region. Metastasis occurred in 58% of the cases, mostly to regional lymph nodes. All poorly differentiated SCCs had evidence of metastasis. Morphological patterns characterized by islands and ribbons of neoplastic keratinocytes were more prominent in well differentiated SCCs. These patterns varied greatly in moderately differentiated SCCs. Poorly differentiated tumours were characterized by the presence of cellular aggregates and individual cells and these tumours had more marked desmoplasia. A significant positive association was established between lymphoplasmacytic inflammatory infiltration and tumour-associated tissue eosinophilia. Evaluation of argyrophylic nucleolar organizer regions (AgNORs) revealed higher proliferation indices in poorly differentiated tumours than in moderately or well differentiated lesions. There was significant correlation between the AgNOR index and histological grading. The morphological factors analyzed were all related to histological grading, which is the major factor predicting the biological behaviour of SCCs in cattle naturally exposed to bracken fern. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Distribution patterns of ferns and lycophytes in the Coastal Region of the state of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Felipe Gonzatti

    2016-01-01

    Full Text Available ABSTRACT A survey of ferns and lycophytes of the Coastal Region of the state of Rio Grande do Sul (CRRS was performed based on field work and collections of the main regional herbaria. The following were evaluated for each species: preferential habits (terrestrial, epiphytic or aquatic, geographic distribution patterns and habitats (forest, grassland, and wetland. The occurrence of a latitudinal gradient in diversity was tested over five latitudinal ranges using the Sørensen Similarity Index. A total of 17 lycophyte and 206 fern species representing 28 families was found between the latitudes of 29° and 34°S. Exclusively terrestrial species were predominant (162, with the majority (113 exhibiting wide Neotropical distributions, followed by species that also occurred in the state of Paraná (44. The forest habitat harbored the greatest number of species (159, while grasslands had the fewest (26. Cluster analysis showed pronounced floristic differentiation among latitudinal Ranges III (31°01' to 32°S and IV (32°01' to 31°S, with a similarity index of only 0.41. Our results demonstrate a strong north-to-south reduction in species richness in the study area, which is related to environmental conditions along the latitudinal gradient and, especially, microclimatic differences in the transition zone between the Atlantic Forest and Pampa biomes.

  9. Arbuscular mycorrhizal colonization in field-collected terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns (Osmundaceae, Gleicheniaceae, Plagiogyriaceae, Cyatheaceae).

    Science.gov (United States)

    Ogura-Tsujita, Yuki; Hirayama, Yumiko; Sakoda, Aki; Suzuki, Ayako; Ebihara, Atsushi; Morita, Nana; Imaichi, Ryoko

    2016-02-01

    To determine the mycorrhizal status of pteridophyte gametophytes in diverse taxa, the mycorrhizal colonization of wild gametophytes was investigated in terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns, i.e., one species of Osmundaceae (Osmunda banksiifolia), two species of Gleicheniaceae (Diplopterygium glaucum, Dicranopteris linearis), and four species of Cyatheales including tree ferns (Plagiogyriaceae: Plagiogyria japonica, Plagiogyria euphlebia; Cyatheaceae: Cyathea podophylla, Cyathea lepifera). Microscopic observations revealed that 58 to 97% of gametophytes in all species were colonized with arbuscular mycorrhizal (AM) fungi. Fungal colonization was limited to the multilayered midrib (cushion) tissue in all gametophytes examined. Molecular identification using fungal SSU rDNA sequences indicated that the AM fungi in gametophytes primarily belonged to the Glomeraceae, but also included the Claroideoglomeraceae, Gigasporaceae, Acaulosporaceae, and Archaeosporales. This study provides the first evidence for AM fungal colonization of wild gametophytes in the Plagiogyriaceae and Cyatheaceae. Taxonomically divergent photosynthetic gametophytes are similarly colonized by AM fungi, suggesting that mycorrhizal associations with AM fungi could widely occur in terrestrial pteridophyte gametophytes.

  10. Acrostichum, a Pioneering Fern of Floodplain Areas from the Late Oligocene Sariñena Formation of the Iberian Peninsula.

    Directory of Open Access Journals (Sweden)

    Rafael Moreno-Domínguez

    Full Text Available Acrostichum is considered today an opportunistic fern in disturbed areas, which indicates the first stages of colonisation of such zones. However, in the fossil record, Acrostichum appears related to fluvio-lacustrine environments, freshwater marshes and mangrove deposits. We report here for first time fossil evidence of Acrostichum that reveals a pioneering behaviour of this fern in the colonisation of perturbed communities in Europe, which corroborates previous assumptions about the paleobiology of Acrostichum. Plant remains were collected from the Chattian (late Oligocene La Val fossil site (Estadilla, Huesca, northeastern Spain belonging to the Sariñena Formation, which mainly embraces crevasse splays, levees and floodplain deposits. Evidence shows that Acrostichum grew within the levee's vegetal community or close to/on the river banks as well as on floodplain areas and closer to/on the shores of ephemeral ponds. But most importantly, the observed co-existence of Equisetum and Acrostichum remains in the same beds indicates that such strata represent short-lived inundated terrains, e.g., floodplains where the water table was temporarily stagnant. Evidence shows wetland environments dominated by pioneering taxa, implying a pioneering role for Acrostichum during the late Oligocene in the Iberian Peninsula.

  11. Chloroplast phylogeny of asplenioid ferns based on rbcL and trnL-F Spacer sequences (Polypodiidae, aspleniaceae) and its implications for biogeography

    NARCIS (Netherlands)

    Schneider, H.; Russell, S.J.; Cox, C.J.; Bakker, F.T.; Henderson, S.; Rumsey, F.; Barrett, J.; Gibby, M.; Vogel, J.C.

    2004-01-01

    Molecular phylogenies have been generated to investigate relationships among species and putative segregates in Asplenium, one of the largest genera in ferns. Of the ~700 described taxa, 71 are included in a phylogenetic analysis using the chloroplast rbcL gene and trnL-F spacer. Our results support

  12. A new schizaeaceous fern, Schizaeopsis ekrtii sp nov., and its in situ spores from the Upper Cretaceous (Cenomanian) of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Kvaček, J.; Dašková, Jiřina; Pátová, R.

    2006-01-01

    Roč. 140, 1-2 (2006), s. 51-60 ISSN 0034-6667 R&D Projects: GA ČR GA205/03/1267 Institutional research plan: CEZ:AV0Z30130516 Keywords : fern * palaeobotany * spores * Cenomanian Subject RIV: EF - Botanics Impact factor: 1.170, year: 2006

  13. Contrasting Patterns of Genetic Variation in Central and Peripheral Populations of Dryopteris fragrans (Fragrant Wood Fern) and Implications for Colonization Dynamics and Conservation

    Science.gov (United States)

    J. R. Bouchard; D. D. Fernando; S.W. Bailey; J. Weber-Townsend; D. J. Leopold

    2017-01-01

    Premise of research. Ferns are vital components of temperate and tropical ecosystems, but they have not been examined in the context of a central-peripheral hypothesis. Dryopteris fragrans is an ideal species to examine the genetic variation between central and peripheral populations because of its arctic north to temperate...

  14. Metabolic adaptation, a specialized leaf organ structure and vascular responses to diurnal N2 fixation by nostoc azollae sustain the astonishing productivity of azolla ferns without nitrogen fertilizer

    NARCIS (Netherlands)

    Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A.; Tazelaar, Anne O.E.; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P.M.; Schluepmann, Henriette

    2017-01-01

    Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf

  15. Can stands of fern Athyrium distentifolium (Opiz) reduce leaching of base cations from soil similarly as grass stands do in mountain areas under enhanced nitrogen input?

    Czech Academy of Sciences Publication Activity Database

    Tůma, Ivan; Fiala, Karel; Holub, Petr

    2008-01-01

    Roč. 1, č. 2 (2008), s. 179-182 ISSN 1803-2451 R&D Projects: GA AV ČR(CZ) IAA600050616 Institutional research plan: CEZ:AV0Z60050516 Keywords : fern stands * leaching of calcium * nitrogen input Subject RIV: EF - Botanics

  16. Revision of the Pennsylvanian fern .i.Boweria./i. Kidston and the establishment of the new genus .i.Kidstoniopteris./i.

    Czech Academy of Sciences Publication Activity Database

    Frojdová, Jana; Pšenička, J.; Bek, Jiří; Cleal, Ch. J.

    2017-01-01

    Roč. 236, January (2017), s. 33-58 ISSN 0034-6667 R&D Projects: GA ČR(CZ) GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Boweria * Kidstoniopteris * fern * Pennsylvanian * in situ spores * taxonomy * cuticles Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

  17. Un texto inédito de Wenceslao Fernández Flórez. "¡S.O.S.! ¡Aquí Europa!"

    Directory of Open Access Journals (Sweden)

    María Teresa BARBADILLO

    2009-11-01

    Full Text Available Publicamos aquí un texto inédito de Wenceslao Fernández Flórez contenido en 23 cuartillas escritas de su puño y letra, que me fueron confiadas generosamente por sus sobrinos Wenceslao y Antonio Fernández Flórez. El manuscrito no lleva fecha alguna, y el sobre que lo contenía sólo reproduce el título, con la indicación «Charla radiofónica». Don Antonio Fernández Flórez tiene idea de que data de 1934 ó 35, posiblemente del mes de octubre. No obstante, ni en la prensa de esos años, ni en los archivos del Servicio de Documentación escrita de Radio Nacional de España —en donde nos atendieron con suma amabilidad— queda constancia de esta intervención de Fernández Flórez a través de las ondas.

  18. Detection of Ptaquilosides in different phenologic stages of Bracken fern (Pteridium aquilinum) and analysis of milk samples in farms with hematuria in Tolima, Colombia

    Science.gov (United States)

    Bracken fern or “Helecho Macho” (Pteridium aquilinum) is one of the most common weeds in the meadows of the mountain ranges of Colombia. Consumption of this palatable plant by bovines causes a disease known as bovine enzootic hematuria and esophageal neoplasia. The toxic effect of the plant in bovin...

  19. Elemental concentration of a native fern from Greece that grows in a monoculture and of corn plants grown in the same soil with different levels of copper

    Energy Technology Data Exchange (ETDEWEB)

    Procopiou, J. (Ministry of Agriculture, Athens, Greece); Wallace, A.

    1982-07-01

    Analysis of a native fern (Pteridium aquilinum L.) growing in large tracts of soil at about 1200 meters mean sea level in Greece indicated that it tolerated low levels of copper. Corn plants (Zea mays L.) grown in potted soil from the area did respond slightly to Cu added to the soil.

  20. Rapid response of leaf photosynthesis in two fern species Pteridium aquilinum and Thelypteris dentata to changes in CO2 measured by tunable diode laser absorption spectroscopy.

    Science.gov (United States)

    Nishida, Keisuke; Kodama, Naomi; Yonemura, Seiichiro; Hanba, Yuko T

    2015-09-01

    We investigated stomatal conductance (g(s)) and mesophyll conductance (g(m)) in response to atmospheric CO2 concentration [CO2] in two primitive land plants, the fern species Pteridium aquilinum and Thelypteris dentata, using the concurrent measurement of leaf gas exchange and carbon isotope discrimination. [CO2] was initially decreased from 400 to 200 μmol mol(-1), and then increased from 200 to 700 μmol mol(-1), and finally decreased from 700 to 400 μmol mol(-1). Analysis by tunable diode laser absorption spectroscopy (TDLAS) revealed a rapid and continuous response in g m within a few minutes. In most cases, both ferns showed rapid and significant responses of g m to changes in [CO2]. The largest changes (quote % decrease) were obtained when [CO2] was decreased from 400 to 200 μmol mol(-1). This is in contrast to angiosperms where an increase in g(m) is commonly observed at low [CO2]. Similarly, fern species observed little or no response of g(s) to changes in [CO2] whereas, a concomitant decline of g(m) and g(s) with [CO2] is often reported in angiosperms. Together, these results suggest that regulation of g(m) to [CO2] may differ between angiosperms and ferns.

  1. Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots.

    Science.gov (United States)

    de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schluepmann, Henriette; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

    2016-01-01

    The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises the questions of how auxin and cytokinin govern fern root system architecture and whether this can tell us something about the origin of that root. Using Azolla filiculoides, we characterized the influence of IAA and zeatin on adventitious fern root meristems and vasculature by Nomarski microscopy. Simultaneously, RNAseq analyses, yielding 36,091 contigs, were used to uncover how the phytohormones affect root tip gene expression. We show that auxin restricts Azolla root meristem development, while cytokinin promotes it; it is the opposite effect of what is observed in Arabidopsis. Global gene expression profiling uncovered 145 genes significantly regulated by cytokinin or auxin, including cell wall modulators, cell division regulators and lateral root formation coordinators. Our data illuminate both evolution and development of fern roots. Promotion of meristem size through cytokinin supports the idea that root meristems of euphyllophytes evolved from shoot meristems. The foundation of these roots was laid in a postembryonically branching shoot system. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  2. Sporophyte morphology and gametophyte development of the fern Blechnum sprucei (Pteridophyta: Blechnaceae).

    Science.gov (United States)

    Gabriel y Galán, Jose María; Passarelli, Lilian M; Prada, Carmen; Rolleri, Cristina H

    2008-12-01

    The fern Blechnum sprucei grows in Mesoamerica (Costa Rica) and South America, from Colombia to Bolivia, SE and centre of Brazil, Paraguay and Argentina. It is a distinctive, somewhat vulnerable, mostly orophilous species. Fresh and dry herbarium material was used for this study. Herbarium material for anatomical studies comes from CTES, BA, LP, MA, SI and UC (Holmgren et al. 1990). Selected representative specimens are additionally cited after taxonomic treatment of the species. Dry material was restored with aqueous 4:1 butil cellosolve. Pinnae were cleared with aqueous 6% NaOH, then coloured with aqueous 1% TBO (Gurr 1966). Hand made transverse sections of young and adult stipes, and costae were done in fresh and restored herbarium material. Venation and epidermal patterns were analyzed in basal, apical and medium pinnae, but only the latter were illustrated. The size and density of stomata were measured in medium pinnae from all studied samples, values shown are the average of 25 measures per sample; sizes are expressed as minimum, media and maximum length x width, in microm, and density as minimum, media and maximum number of stomata/ mm2. Spores were studied with SEM, mounted on metal stubs with double sided tape, covered with gold under vacuum and photographed with a Jeol /EO JSM 6360 (15 KV) SEM. Spores were also studied with light microscope, mounted in DePeX (DePeX mounting medium, Gurr, BDH Laboratory Supplies, Poole BH15 1TD, UK) and measured using an ocular micrometer. Measurements are based on a minimum sample of 100 spores taken from different specimens. Sizes are expressed as the longest equatorial diameter/ polar diameter, in microm. Gametophytes were studied from material collected in the subtropical forest of Tucumán Province, Argentina. Spore samples for cultures were taken from single sporophytes kept dry at room temperature since the date plants were collected. Gametophytes were grown under fluorescent light. Multispore cultures were

  3. Botanical and geological significance of potassium-argon dates from the Juan Fernández Islands

    Science.gov (United States)

    Stuessy, Tod F.; Foland, K.A.; Sutter, John F.; Sanders, Roger W.; Silva, O. Mario

    1984-01-01

    Potassium-argon dating of five basalts from the three main islands of the Juan Fernández (or Robinson Crusoe) Islands of Chile in the southeastern Pacific gives ages of 1.01 ± 0.12 and 2.44 ± 0.14 million years for Masafuera, 3.79 ± 0.20 and 4.23 ± 0.16 for Masatierra, and 5.8 ± 2.1 for Santa Clara. These ages are much younger than that of the underlying oceanic plate and are consistent with the origin of the island-seamount chain from a mantle hot spot beneath the eastward moving Nazca plate. The young age for the archipelago suggests that speciation within endemic genera has occurred within the past 4 to 5 million years. Endemic genera of apparently more ancient origins, such as Lactoris and Thyrsopteris, have apparently dispersed to the islands and survive refugially.

  4. Biostratigraphic evidence of dramatic Holocene uplift of Robinson Crusoe Island, Juan Fernández Ridge, SE Pacific Ocean

    Science.gov (United States)

    Sepúlveda, P.; Le Roux, J. P.; Lara, L. E.; Orozco, G.; Astudillo, V.

    2014-09-01

    A study of the biostratigraphy and sedimentology of Holocene deposits on Robinson Crusoe Island (RCI) on the Juan Fernández Ridge (JFR) indicates that a~dramatic but localized uplift occurred since 8000 BP, at a rate of about 8.5 mm yr-1. In fact, supratidal flats and sand layers with marine gastropods (mostly Nerita sp.) are now exposed ca. 70 m a.s.l., and covered by transitional dunes. The last volcanic activity on RCI occurred at ca. 0.8 Ma (active hotspot located 280 km further west) and there is no sign of a compensating bulge that explains this uplift, isobaths of the sea floor instead suggesting general subsidence. However, modeling indicates that large-scale landslides followed by isostatic rebound are a viable explanation, partially reflected in the low-resolution bathymetry of the area.

  5. Richness of ferns and lycophytes in a gallery forest in the central region of Mato Grosso do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Rodrigo Lehn

    2013-03-01

    Full Text Available This paper presents the floristic survey of ferns and lycophytes occurring in a gallery forest in the central region of Mato Grosso do Sul, Brazil. In the study area, 29 species and 2 varieties were recorded. Dryopteridaceae and Pteridaceae were the richest families (8 and 5 species, respectively and Elaphoglossum and Blechnum were the richest genera (3 species each one. Preferably, the listed species occur within the forest (68%, they occupy the terrestrial substrate (77.4%, and they are hemicryptophyte (77.4% and rosulate (64.5%. We observed four species still not mentioned for Mato Grosso do Sul, which are Blechnum lanceola L., Elaphoglossum pachydermum (Fée T. Moore, Lindsaea lancea (L. Bedd var lancea, and Mickelia nicotianifolia (Sw. R. C. Moran et al., which has its southern limit of distribution in Brazil, in the study area.

  6. THE EFFECT OF Anredera cordifolia (Ten. Steenis SUPPLEMENTATION ON UTERINE INVOLUTION PROCESS EVALUATED BY OESTRUS POST PARTUM BEHAVIOR AND FERNING

    Directory of Open Access Journals (Sweden)

    R. Purwasih

    2014-09-01

    Full Text Available The aim of this study was to determine the effect of Anrederacordifolia (Ten. Steenissupplementation on uterine involution process in rabbit. The research design applied was completelyrandomized design with 4 treatments and 3 replications (T0 = without Anredera cordifoliasupplementation; TI = Anredera cordifolia supplemented two days before parturition; T2 = Anrederacordifolia supplemented two days after parturition; T3 = Anredera cordifolia supplemented two daysbefore until two days after parturition. The results showed that Anredera cordifolia (Ten. Steenissupplementation could accelerate post partum oestrus in does that were characterized by post partumoestrus behavior, ferning of saliva and cervical mucus. The best treatment was T3, that was four daysAnredera cordifolia supplementation that was administered at 0.45 g/kg of body weight/day. Furtherresearch was needed to find an optimal dose of Anredera cordifolia (Ten. Steenis on uterine involution.

  7. Strong congruence in tree and fern community turnover in response to soils and climate in central Panama

    DEFF Research Database (Denmark)

    Jones, Mirkka; Ferrier, Simon; Condit, Richard

    2013-01-01

    and seasonality undoubtedly limit plant distributions in this region, soil effects are at least as important, and interactions between the two are sizeable. This is likely to hold elsewhere in the Caribbean region, where mosaics of marine and volcanic soils combined with pronounced rainfall gradients are common......1. Plant species turnover in central Panamanian forests has been principally attributed to the effects of dispersal limitation and a strong Caribbean to Pacific gradient in rainfall seasonality. Despite marked geological heterogeneity, the role of soil variation has not been rigorously examined. 2....... We modelled the compositional turnover of trees and ferns in the Panama Canal watershed as a function of soil chemistry, climate and geographical separation, using generalized dissimilarity models (GDMs). 3. Predictability in both plant groups was strong, with 74% of turnover explained in trees...

  8. Multilocus genetic structure at contrasted spatial scales of the endangered water fern Marsilea strigosa Willd. (Marsileaceae, Pteridophyta).

    Science.gov (United States)

    Vitalis, Renaud; Riba, Miquel; Colas, Bruno; Grillas, Patrick; Olivieri, Isabelle

    2002-07-01

    Marsilea strigosa (Marsileaceae, Pterydophyta) is a rare water fern found in the Mediterranean basin, in temporary flooded habitats only. We analyzed the level and the distribution of genetic variation at seven microsatellite loci, both at the Mediterranean scale and at a narrower scale within a highly fragmented French metapopulation. Genetic diversity among individuals within each pond suggests that M. strigosa reproduces predominantly through selfing. The very high population differentiation at the Mediterranean scale indicates that gene flow (if any) is highly restricted. Similar differentiation is also found at the scale of a single metapopulation. The distribution of multilocus genotypes suggests that the genetic variation in this species is maintained mainly through the interplay of mutation and low recombination.

  9. De mujeres deseadas a mujeres deseantes: entrevista con Ana María Fernández

    OpenAIRE

    Fernández, Ana María

    1997-01-01

    Esta entrevista se realizó a su paso por Bogotá, cuando participó como docente invitada en los cursos de postgrado del Programa de Estudios de Género, Mujer y Desarrollo de la Facultad de Ciencias Humanas de la Universidad Nacional de Colombia. Ana María Fernández, psicóloga clínica y psicoanalista, profesora de Estudios de la Mujer y Técnica de Grupos de la Facultad de Psicología de la Universidad de Buenos Aires, autora del libro "La Mujer de la Ilusión" (Paidós, 1993) y de numerosos artícu...

  10. Iridoids of Chemotaxonomy Relevance, a New Antirrhinoside Ester and Other Constituents from Kickxia spuria subsp. integrifolia (Brot.) R.Fern.

    Science.gov (United States)

    Venditti, Alessandro; Frezza, Claudio; Serafini, Ilaria; Ciccòla, Alessandro; Sciubba, Fabio; Serafini, Mauro; Bianco, Armandodoriano

    2018-02-01

    In this work, the secondary metabolite content of the EtOH extract of Kickxia spuria subsp. integrifolia (Brot.) R.Fern. is reported. Fourteen compounds were isolated and identified by means of column chromatography and NMR and MS instrumental techniques, respectively. Among the identified compounds, the chemotaxonomic markers of the species were evidenced, whereas others were reported for the first time in the genus. Among these, a new antirrhinoside derivative (12) was recognized. The iridoid content showed a molecular pattern very similar to those reported for other taxa comprised in the Antirrhinae tribe of Plantaginaceae, thus providing an additional evidence that supports the current botanical classification of the Kickxia genus. Anyway, most of the recognized components are able to exert important pharmacological properties which might suggest the possible employment of also this species in traditional medicine just like it happens for some other species of the Kickxia genus. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  11. Benito Fernández de Elena Garro: una mirada crítica sobre la historia mexicana

    Directory of Open Access Journals (Sweden)

    Gerardo Bustamante Bermúdez

    2017-07-01

    Full Text Available En 1957, Elena Garro escribió la obra teatral Benito Fernández, texto en el que hace una revisión crítica a la historia nacional, el poder, la simulación y la búsqueda de la identidad personal en medio de la sociedad creada a partir de la posrevolución mexicana. La obra de la escritora es un contradiscurso a la oficialidad, a la mitificación de los hechos y héroes nacionales; lo que le interesa es resaltar el carácter racista y clasista de una nueva sociedad de dirigentes políticos en busca del bienestar personal y de grupo por encima del bien colectivo, para ello, opta porque en su obra los personajes se preocupen por comprar una cabeza, es decir, una ideología que les haga saber que existen. In 1957, Elena Garro wrote the play Benito Fernández, a text in which she critically reviews Mexico's national history, issues of power, simulation and the quest for personal identity in the midst of a society emerged in the after effects of the Mexican Revolution. This work is a counter-discourse to Mexico's official narrative and the idealization of facts and national heroes. She is interested in the racist and classist aspects of the new dominating society, which is interested in their own personal welfare over those of the collective. To do so, she makes her characters concerned about buying a head, that is, an ideology to fundament their own existence.

  12. Rock paintings in Fern Cave, Lava Beds National Monument, California: Not the 1054 A.D. (Crab Nebula) Supernova

    International Nuclear Information System (INIS)

    Armitage, R.A.; Hyman, M.; Rowe, M. W.

    1997-01-01

    On July 4, 1054 A.D. a supernova brighter than Venus appeared in the sky, remaining visible for approximately 23 days and 650 nights. It was chronicled in five independent historic accounts, four in China and one in Japan. For at least 40 years investigators have attributed certain distinctive rock paintings and carvings in the western United States as recordings of the 1054 A.D. supernova. More than twenty such depictions (circle or star-like symbols and a crescent) have been located. Two panels of rock paintings in Lava Beds National Monument, California, one at Fern Cave and one at Symbol Bridge, were listed as recording the 1054 A.D. supernova. The only direct means of assessing the likelihood that a 'supernova' representation records the 1054 A.D. event is to date the rock painting or carving. At Texas A and M University, was developed a plasma-chemical extraction technique that permits to analyze the 14 C in rock paintings, whether the pigments used were charcoal or inorganic Fe- and Mn- oxides and hydroxides with organic binder/vehicles. This paper presents direct 14 C age estimates on a rock painting suggested to represent the 1054 A.D. supernova. Charcoal pigment samples were collected from three figures in proximity at Fern Cave: a crescent pointing downward and two nearby circles, one above and one below the crescent. The AMS 14 C analysis on each sample using this technique show that these images do not represent the 1054 A.D. supernova

  13. El manuscrito jerezano de La Mojigata, comedia de Leandro Fernández de Moratín

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    López Romero, José

    2003-12-01

    Full Text Available The volume found in the Public Library of Jerez containing three Spanish Comedies by Leandro Fernández de Moratín, has the enormous importance of including first editions of both The new comedy (1792 and The old man and the little girl (1790, and especially a manuscript copy of The prude, a work which circulated in literary circles of Madrid during the early 1790s, and being even performed in some of them without Moratin's permission. This article tries to compare the Jerez manuscript copy with others already known, and with final edition of de work, and at the same time to shed some light on the identity of the owner of the volume where The prude is included.El volumen encontrado en la Biblioteca Municipal de Jerez de la Frontera con tres Comedias españolas de Leandro Fernández de Moratín, tiene el enorme valor de incluir primeras ediciones de La comedia nueva (1792 y de El viejo y la niña (1790 y, sobre todo, una copia manuscrita de La mojigata, obra que en los primeros años de la década de 1790 circuló de esa forma por tertulias madrileñas, en algunas de las cuales hasta se representó sin el consentimiento de Moratín. Este trabajo intenta cotejar la copia manuscrita jerezana con otras ya conocidas y con la edición definitiva de la obra, así como arrojar alguna luz sobre la identidad del propietario del volumen en el que aquélla se incluye.

  14. A total-evidence phylogeny of the lady fern genus Athyrium Roth (Athyriaceae) with a new infrageneric classification.

    Science.gov (United States)

    Wei, Ran; Ebihara, Atsushi; Zhu, Yan-Mei; Zhao, Cun-Feng; Hennequin, Sabine; Zhang, Xian-Chun

    2018-02-01

    The lady fern genus Athyrium represents one of the most diversified lineages in Athyriaceae with about 160-220 known species, and is notorious for its taxonomic difficulty. Despite progress in recent phylogenetic studies involving this genus, it still lacks a modern systematic and taxonomic update using integrative analyses of molecular and morphological evidence based on a broad species sampling. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the genus to date based on a total-evidence approach, covering all formerly accepted segregates within the athyrioid ferns. We sampled up to eight plastid markers and 20 morphological characters for each species. Our analyses, including maximum parsimony, maximum likelihood and Bayesian inference, yield a robust phylogenetic framework. We find that Athyrium is not monophyletic by recovering Athyrium skinneri and A. alpestre nested with Anisocampium and Cornopteris respectively while Pseudocystopteris is included in Athyrium. Furthermore, eight well-resolved clades and two isolated species within Athyrium are found in the phylogenetic topology, which can be also characterized by morphological synapomorphies from traits of petioles, leaves, sori and spores. In the interest of recognizing monophyletic taxa with morphological synapomorphies, we agree with the inclusion of Pseudocystopteris in Athyrium as proposed in previous studies, but treat Anisocampium and Cornopteris as separate genera. We further propose to resurrect a monotypic Pseudathyrium to accommodate A. alpestre. Based on morphological characters and molecular phylogeny, a new infrageneric classification system of Athyrium is proposed which subdivided it into ten sections, and one New-World species A. skinneri is transferred into Anisocampium. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Inventorying of the tree fern Genus Cibotium of Sumatra: Ecology, population size and distribution in North Sumatra

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    TITIEN NGATINEM PRAPTOSUWIRYO

    2011-10-01

    Full Text Available Praptosuwiryo TNg, Pribadi DO, Puspitaningtyas DM, Hartini S (2011 Inventorying the tree fern Genus Cibotium of Sumatra: Ecology, population size and distribution in North Sumatra. Biodiversitas 12: 204-211. Cibotium is one tree fern belongs to the family Cibotiaceae which is easily differentiated from the other genus by the long slender golden yellowish-brown smooth hairs covered its rhizome and basal stipe with marginal sori at the ends of veins protected by two indusia forming a small cup round the receptacle of the sorus. It has been recognized as material for both traditional and modern medicines in China, Europe, Japan and Southeast Asia. Population of Cibotium species in several countries have decreased rapidly because of over exploitation and there is no artificial cultivation until now. The aims of this study were: (i To re-inventory the species of Cibotiun in North Sumatra, (ii to record the ecology and distribution of each species, and (iii to assess the population size of each species. Field study was carried out by using random search with belt transect. Two species were recorded, namely C. arachnoideum dan C. barometz. The geographical distribution of the two species in North Sumatra are presented. Cibotium is commonly growing terrestrially on opened or rather opened areas in secondary forets and primary forest at hills or lower mountains with a relatively high humidity at 30-90º slopes. C. arachnoideum has a strict distribution and only found at 1740-1770 m a.s.l. in primary forest, whereas C. barometz has a broad distribution in secondary forest at elevation range from 650-1200 m.

  16. Sporophyte morphology and gametophyte development of the fern Blechnum sprucei (Pteridophyta: Blechnaceae

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    Jose María Gabriel y Galán

    2008-12-01

    Full Text Available The fern Blechnum sprucei grows in Mesoamerica (Costa Rica and South America, from Colombia to Bolivia, SE and centre of Brazil, Paraguay and Argentina. It is a distinctive, somewhat vulnerable, mostly orophilous species. Fresh and dry herbarium material was used for this study. Herbarium material for anatomical studies comes from CTES, BA, LP, MA, SI and UC (Holmgren et al.1990. Selected representative specimens are additionally cited after taxonomic treatment of the species. Dry material was restored with aqueous 4:1 butil cellosolve. Pinnae were cleared with aqueous 6% NaOH, then coloured with aqueous 1 % TBO (Gurr 1966. Hand made transverse sections of young and adult stipes, and costae were done in fresh and restored herbarium material. Venation and epidermal patterns were analyzed in basal, apical and medium pinnae, but only the latter were illustrated. The size and density of stomata were measured in medium pinnae from all studied samples, values shown are the average of 25 measures per sample; sizes are expressed as minimum, media and maximum length x width, in µm, and density as minimum, media and maximum number of stomata / mm². Spores were studied with SEM, mounted on metal stubs with double sided tape, covered with gold under vacuum and photographed with a Jeol /EO JSM 6360 (15 KV SEM. Spores were also studied with light microscope, mounted in DePex (DePex mounting medium, Gurr, BDH Laboratory Supplies, Poole BH15 1TD, UK and measured using an ocular micrometer. Measurements are based on a minimum sample of 100 spores taken from different specimens. Sizes are expressed as the longest equatorial diameter/ polar diameter, in µm. Gametophytes were studied from material collected in the subtropical forest of Tucumán Province, Argentina. Spore samples for cultures were taken from single sporophytes kept dry at room temperature since the date plants were collected. Gametophytes were grown under fluorescent light. Multispore cultures

  17. Present, past and future of the European rock fern Asplenium fontanum: combining distribution modelling and population genetics to study the effect of climate change on geographic range and genetic diversity.

    Science.gov (United States)

    Bystriakova, Nadia; Ansell, Stephen W; Russell, Stephen J; Grundmann, Michael; Vogel, Johannes C; Schneider, Harald

    2014-02-01

    Climate change is expected to alter the geographic range of many plant species dramatically. Predicting this response will be critical to managing the conservation of plant resources and the effects of invasive species. The aim of this study was to predict the response of temperate homosporous ferns to climate change. Genetic diversity and changes in distribution range were inferred for the diploid rock fern Asplenium fontanum along a South-North transect, extending from its putative last glacial maximum (LGM) refugia in southern France towards southern Germany and eastern-central France. This study reconciles observations from distribution models and phylogeographic analyses derived from plastid and nuclear diversity. Genetic diversity distribution and niche modelling propose that genetic diversity accumulates in the LGM climate refugium in southern France with the formation of a diversity gradient reflecting a slow, post-LGM range expansion towards the current distribution range. Evidence supports the fern's preference for outcrossing, contradicting the expectation that homosporous ferns would populate new sites by single-spore colonization. Prediction of climate and distribution range change suggests that a dramatic loss of range and genetic diversity in this fern is possible. The observed migration is best described by the phalanx expansion model. The results suggest that homosporous ferns reproducing preferentially by outcrossing accumulate genetic diversity primarily in LGM climate refugia and may be threatened if these areas disappear due to global climate change.

  18. La poética de la Nocilla: Transmedia Poetics in Agustín Fernández Mallo’s Complete Works.

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    Alex Saum-Pascual

    2014-06-01

    Full Text Available Moving beyond current applications of transmedia storytelling, this essay looks at the work of Spanish author Agustín Fernández Mallo to explore how his engagement with the media landscape is both a revolution and a contribution to fundamental concepts in contemporary literature such as authorship and narrative structure. On the one hand, transmedia storytelling provides a structure to frame Fernández Mallo’s versatile and multimedia production, exploring both the productive semiotic intermedial breakages within works, as well as analyzing his complete production as a whole: one single poetic “work” encapsulated into a transmedia universe composed of multiple autonomous narratives. On the other, the fictionalization of his Author function as a parodied metafictional object within this transmedia universe can shed some light on the role of the writer within a larger network of media convergence and neoliberal enterprises.

  19. Ptaquiloside, the major carcinogen of bracken fern, in the pooled raw milk of healthy sheep and goats: an underestimated, global concern of food safety.

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    Virgilio, Antonella; Sinisi, Annamaria; Russo, Valeria; Gerardo, Salvatore; Santoro, Adriano; Galeone, Aldo; Taglialatela-Scafati, Orazio; Roperto, Franco

    2015-05-20

    Bracken fern (Pteridium aquilinum) is a worldwide plant containing toxic substances, which represent an important chemical hazard for animals, including humans. Ptaquiloside, 1, a norsesquiterpenoid glucoside, is the major carcinogen of bracken detected in the food chain, particularly in the milk from farm animals. To date, ptaquiloside has been shown in the milk of cows feeding on a diet containing bracken fern. This is the first study that shows the systematic detection of ptaquiloside, 1, and reports its direct quantitation in pooled raw milk of healthy sheep and goats grazing on bracken. Ptaquiloside, 1, was detected by a sensitive method based on the chemical conversion of ptaquiloside, 1, into bromopterosine, 4, following gas chromatography-mass spectrometry (GC-MS) analysis. The presence of ptaquiloside, 1, possibly carcinogenic to humans, in the milk of healthy animals is an unknown potential health risk, thus representing a harmful and potential global concern of food safety.

  20. Mesobathic chondrichthyes of the Juan Fernández seamounts: are they different from those of the central Chilean continental slope?

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    Isabel Andrade

    2008-03-01

    Full Text Available We compared the geographic distribution of groups of chondrychthid fishes of two physically proximal, although geographically different, regions that include the Juan Fernández seamounts and the central Chilean continental slope, both sampled at mesopelagic and mesobenthonic depths. The ridge is in the Nazca Plate, while the slope region in on the South American Plate, and is closer to the South American continent. We found six species of Chondrichthyes for the seamounts (four orders, four families. The slope sampling produced ten species of Chondrichthyes, of which Torpedo tremens De Buen 1959, was the only species in common with the Juan Fernández area. There are clear differences between the Chondrichthyes of the two regions. These fisheries require adequate administrative modes. Rev. Biol. Trop. 56 (1: 181-190. Epub 2008 March 31.

  1. Algunas novelas de Darío Fernández-Flórez: de Zarabanda (1944 a Alta Costura (1954. Temas escabrosos en tiempos de restricciones moralistas

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    Montejo Gurruchaga, Lucía

    2008-06-01

    Full Text Available Dario Fernández-Flórez begins in 1944 with Zarabanda a narrative style of intellectual eroticism and inmoral atmosphere which attracted no attention. Six years later he published Lola, espejo oscuro the recollections of a high prostitute. The novel was an scandal and an immediate success. Although the topic and its treatment were odd at the time because the strict moral values which mantained Franco´s regime were ignored, the novel was published with no cuts at all. Censorship was deaf to all the voices that warned of its dangers. This had an explanation: Darío Fernández-Flórez held an important post in the Propaganda National Service. After his dismissal censors were less lenient.Darío Fernández-Flórez inicia en 1944 con Zarabanda una narrativa de erotismo intelectualizado y ambiente amoral que no tuvo ningún eco. Seis años después publicará Lola, espejo oscuro, las memorias de una prostituta de alto copete. La novela suscitó un gran escándalo y su éxito fue inmediato. Aunque el tema y su tratamiento eran inusitados en aquellos momentos porque la obra daba al traste con los estrictos valores morales que sustentaban el régimen franquista, la novela fue publicada sin recortes; la censura hizo oídos sordos a todas las voces que alertaban de su peligro. Este hecho tiene una explicación: Darío Fernández-Flórez ocupaba un cargo importante en el Servicio Nacional de Propaganda. Tras su cese, los censores serán menos benevolentes.

  2. Comparisons of micrometeorology, growth of leather-fern [Rumohra adiantiformis, pteridophyta] and comfortable working environment between PO-film-covered and net-covered greenhouses in summer

    International Nuclear Information System (INIS)

    Yokoyama, H.; Harazono, Y.

    2004-01-01

    Protected cultivation of leather-fern in Hachijo-Island has been urged to prevent the Mottled Yellowing Syndrome (MYS) damage and to reduce the production costs. The purpose of the study was to reveal greenhouse environments that would provide good plant growth, a comfortable working environment and low-cost management, by comparing the micrometeorology and leatherfern productivity between Poly-Olefin (PO) film-covered greenhouses and the conventional netcovered greenhouses. Both greenhouses were fully covered by the same net. Field studies of leather-fern cultivation in Hachijo-Island showed that better productivity and quality of leather-fern have been provided by farmer's net-covered greenhouses than by farmer's PO-covered greenhouses. The light transmittance in the net-covered greenhouse was higher and the air temperature was lower than those in the PO-covered greenhouse. The comparative experiments using PO-covered greenhouses (PO), and net-covered greenhouses (NET), were conducted at the Hachijojima Horticultural Research Center. Air temperature and its vertical gradient in NET were lower than those in PO. Irrigation in PO was 225 mm during August and September in 1999, but 507 mm of precipitation in addition to the irrigation was supplied in NET. Air temperature and its vertical gradient in PO increased with solar radiation increase. Heat disorder in working environments for farmers did not occur in the NET, but several warning hours of heat disorder occurred in the PO as a dangerous working environment. The NET was thought to be a better system of leather-fern cultivation bringing about low costs and comfortable working environments. However, further application of fully rolled-up PO-film greenhouse system was recommended to control the soil water condition

  3. Almost the Same, but Not Quite: Re-Orienting the Story of the Subject in Christina Fernández Cubas's El año de Gracia

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    Jessica A. Folkart

    2002-06-01

    Full Text Available Cristina Fernández Cubas's novel El año de Gracia (1985, about a young Spaniard who is shipwrecked on a deserted island with only a mangy shepherd for company, evokes the political dialectics of self/other found in the European's discovery and conquest of an unknown island in Robinson Crusoe . In Fernández Cubas's literary depiction of the European subject, however, she situates him on the margins of power in order to view the dynamic from a different perspective. The postcolonial theorizations of Edward Said and Homi Bhabha inform this analysis of how Fernández Cubas's castaway is at first overpowered by the other and then, in his struggle for control, comes to appreciate and learn from those different qualities instead of subsuming them beneath his personal dominance. While the Spanish novel clearly foregrounds Robinson Crusoe as its model text, it also reorients the once supreme subject in the site of exclusion. Hence this protagonist tells his story from a newly formed, hybrid perspective of the oppressor and the oppressed melded into one. El año de Gracia engages conflicting visions of power in dialogue with one another, interrogating the borders that define them according to the differences they exclude. In the process, it disorients the subject in order to reorient the story that he tells as one that is almost the same as its literary forebear but, importantly, not quite.

  4. Richness, geographic distribution and ecological aspects of the fern community within the Murici Ecological Station in the state of Alagoas, Brazil

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    Anna Flora de Novaes Pereira

    2013-12-01

    Full Text Available We conducted a floristic survey of ferns within the Murici Ecological Station (remnant of the northeastern Atlantic Forest, located near the municipalities of Messias and Murici, in the state of Alagoas, Brazil. To increase knowledge of the ferns of Alagoas, we evaluated the species occurring in the study area in terms of richness, composition, geographic distribution, similarities with species in other Brazilian biomes, regional conservation status and ecological aspects. Data were obtained from field work conducted between March 2009 and September 2010. We identified 107 species of ferns, of which 19 represent new records for Alagoas. The richest families were Pteridaceae (29 species and Polypodiaceae (22 species. The richest genera were Adiantum (15 species and Thelypteris (9 species. Most of the species sampled are widely distributed throughout Brazil and the Americas. Within the context of the northeastern Atlantic Forest, 12 species were considered endangered. Concerning the ecological aspects, 88.8% of the species identified were herbaceous, 57.9% were terrestrial and 70.0% occurred in the forest interior.

  5. The fern-feeder aphids (Hemiptera: Aphididae) from China: a generic account, descriptions of one new genus, one new species, one new subspecies, and keys.

    Science.gov (United States)

    Su, Xiao-Mei; Jiang, Li-Yun; Qiao, Ge-Xia

    2014-02-11

    Fern-feeder aphids (Hemiptera: Aphididae) in China are represented by 13 species in 10 genera, including a new genus, Vietaphis gen nov., a new species, Vietaphis aliquantus sp nov., from Guizhou and Tibet on Plagiogyria japonicum, and a new subspecies, Amphorophora scabripes galba ssp nov., from Guizhou on Pentarhizidium intermedium. Two genera, Amphorophora Buckton and Idiopterus Davis, and four species or subspecies, Amphorophora ampullate ben-galensis Hille Ris Lambers and Basu, Idiopterus nephrelepidis Davis, Micromyzodium polypodii Takahashi, and Myzus filicis Basu, are reported for the first time in China. Apterae and alatae of Myzus filicis are redescribed herein, and with host plant notes. The fern-feeder aphid genus Ne-omacromyzus Lee is considered a junior synonym of Idiopterus. Furthermore, Neomacromyzus cyrtomicola Lee is transferred to the genus Idiopterus, as Idiopterus cyrtomicola (Lee), comb nov., which is herein considered a junior synonym of Idiopterus nephrelepidis Davis. Keys to Chinese fern-feeder species are provided. Morphological figures and biometrical data of Vietaphis aliquantus sp nov., Amphorophora scabripes galba ssp nov., and Myzus filicis are presented. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  6. Juan Fernández Ridge (Nazca Plate): petrology and thermochronology of a rejuvenated hot spot trail

    Science.gov (United States)

    Reyes, J.; Lara, L. E.

    2012-04-01

    The Juan Fernández Ridge on the oceanic Nazca plate is thought to be a classic hot spot trail because of the apparent westward rejuvenation of the eruptive ages. However, geochronological data is still scarce and there are a few constrains to support this hypothesis like the ca. 9 Ma Ar-Ar age of the O'Higgins seamount (115 km from the Chile-Perú trench), some published K-Ar ages of ca. 3-4 Ma in Robinson Crusoe island (580 km from the trench) and ca. 1 Ma in Alejandro Selkirk (180 km further west). New reconnaissance K-Ar ages and specially the ongoing Ar-Ar dating effort in Robinson Crusoe define a ca. 1-4 Ma time span, which partially overlap with the age of Alejandro Selkirk, breaking the expected age progression given that the Nazca plate moves eastwards at ca. 6-8 cm/yr. In addition, new geological mapping shows a sharp unconformity between the older (ca. 4 Ma), strongly altered sequences and the more recent (ca. 1 Ma), post-erosional volcanic piles, where the proximal facies are still preserved. Petrological evidence also supports this evolution pattern. In fact, the partially altered older sequence is tholeiitic (Ba/Yb=12.70; La/Yb=8.12; Ba/Y=6.51; Ba/Zr=0.89). The shield stage (ca. 1-3 Ma) is transicional from tholeiitic to alkaline (Ba/Yb=18.07-8.32; La/Yb=4.59-9.84; Ba/Y=4.24-8.18; Ba/Zr=0.73-1.09) and the younger (ca. 1 Ma) is mostly alkaline (Ba/Yb=38.15; La/Yb=15.66; Ba/Y=20.27; Ba/Zr=2.31). A fixed deep-mantle plume origin for Pacific hot spots has been widely debated and concurrent phenomena arose as a possible explanation for non-linear age progressions and/or long-lived volcanic activity. In fact, intraplate regional tectonics, plume displacement, and mantle heterogeneities could be the main factor of the ridge architecture or the mask for a first-order linear trend. An ongoing mapping and dating effort is aimed to understand the evolution of the Juan Fernández Ridge, testing the main hypothesis. This research is supported by FONDECYT Project

  7. Project "Conservation, Restoration, and Development of the Juan Fernández islands, Chile" Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

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    JAIME G. CUEVAS

    2001-12-01

    Full Text Available From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación Nacional Forestal, CONAF started an ambitious project, whose objective is the recovery of this highly complex ecosystem with a socio-ecological focus. Juan Fernández makes an interesting case, as the local people (600 persons practically live within the park, therefore impeding the exclusion of the people from any conservation program. Secondly, the relatively small size of the archipelago (100 km² permits the observation of the effects of whatever modification in the ecosystem on small scales in time and space. Thirdly, the native and introduced biota are interrelated in such a way that human-caused changes in one species population may provoke unexpected results amongst other, non-target species. The project mainly deals with the eradication or control of some animal and plant plagues, the active conservation and restoration of the flora and the inclusion of the local people in conservation planning. This article presents the park's general problems, the strategy proposed to resolve them as well as some preliminary results. This project shows the complexity of the conservation activities in practice, with diverse and complex interrelations and gaps in ecological knowledge. In this respect, the project may well serve as a model for similar programs in other placesLas islas Juan Fernández albergan una de las floras más interesantes del planeta desde el punto de vista científico. Aunque están protegidas como Parque Nacional y Reserva Mundial de la

  8. Identification guide to Nordic aphids associated with mosses, horsetails and ferns (Bryophyta, Equisetophyta, Polypodiophyta (Insecta, Hemiptera, Aphidoidea

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    Anders Christian Albrecht

    2015-10-01

    Full Text Available Keys and diagnoses of North European aphids (Hemiptera, Aphidoidea associated with mosses, horsetails and ferns are given, based on fresh and freeze-dried material. Numerous externally visible and thus informative characters, that are absent in cleared, slide-mounted specimens, such as body shape colours, wax coating and pattern etc., are utilized. Most of the species are illustrated by photographs of live specimens and drawings. Root-feeding species living in the moss layer or otherwise often present in moss samples are also included, even if their hosts were spermatophytes. The combination of colour images and diagnoses, utilizing easily observed characters, allows the identification of a large number of species already in the field, and many more at home with the aid of a stereo microscope. Host plant relationships and association with ants are summarised, including new records. Brief accounts on aphid life cycles, freeze-drying preparation techniques, etc. are also given to support the use of the keys.

  9. Characterization of the stem anatomy of the Eocene fern Dennstaedtiopsis aerenchymata (Dennstaedtiaceae) by use of confocal laser scanning microscopy.

    Science.gov (United States)

    Shi, Chris S; Schopf, J William; Kudryavtsev, Anatoliy B

    2013-08-01

    Permineralization provides the most faithful known mode of three-dimensional preservation of the morphology and cellular anatomy of fossil plants. Standard optical microscopic documentation of such structures can provide only an approximation of their true three-dimensional form and is incapable of revealing fine-structural (<300 nm) details, deficiencies that can be addressed by the use of confocal laser scanning microscopy (CLSM). To demonstrate the usefulness of CLSM in such studies, we compare confocal laser scanning micrographs and optical photomicrographs of the permineralized tissues of rhizomes and petioles of the Eocene fern Dennstaedtiopsis aerenchymata preserved in cherts of the Clarno Formation of Oregon, USA, and the Allenby Formation (Princeton chert) of British Columbia, Canada. The laser-induced fluorescence detected by CLSM produces crisp high-resolution images of the three-dimensionally permineralized tissues of Dennstaedtiopsis aerenchymata. Tissues analyzed include the epidermis and epidermal hairs, cortex, aerenchyma, endodermis, vascular tissue, and pith-for each of which, CLSM yields results superior to those of standard optical microscopy. CLSM and previous Raman spectroscopic analyses of the same specimens provide evidence consistent with original biochemistry. Use of CLSM to characterize the morphology and cellular anatomy of permineralized fossil plants can provide accurate data in two and three dimensions at high spatial resolution, information that can be critically important to taxonomic, taphonomic, and developmental interpretations. Results presented here from this first detailed CLSM-based study of permineralized plant axes indicate that this nonintrusive, nondestructive technique should be widely applicable in paleobotany.

  10. The rise of the Himalaya enforced the diversification of SE Asian ferns by altering the monsoon regimes

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    Wang Li

    2012-11-01

    Full Text Available Abstract Background The rise of high mountain chains is widely seen as one of the factors driving rapid diversification of land plants and the formation of biodiversity hotspots. Supporting evidence was reported for the impact of the rapid rise of the Andean mountains but this hypothesis has so far been less explored for the impact of the “roof of the world”. The formation of the Himalaya, and especially the rise of the Qinghai–Tibetan Plateau in the recent 20 million years, altered the monsoon regimes that dominate the current climates of South East Asia. Here, we infer the hypothesis that the rise of Himalaya had a strong impact on the plant diversity in the biodiversity hotspot of the Southwest Chinese Mountains. Results Our analyses of the diversification pattern of the derived fern genus Lepisorus recovered evidence for changes in plant diversity that correlated with the strengthening of South East Asian monsoon. Southwest China or Southwest China and Japan was recovered as the putative area of origin of Lepisorus and enhancing monsoon regime were found to shape the early diversification of the genus as well as subsequent radiations during the late Miocene and Pliocene. Conclusions We report new evidence for a coincidence of plant diversification and changes of the climate caused by the uplift of the Himalaya. These results are discussed in the context of the impact of incomplete taxon sampling, uncertainty of divergence time estimates, and limitations of current methods used to assess diversification rates.

  11. A Note on the Re-collection and Conservation of Thelypteris kingii (Thelypteridaceae – an Endemic Fern of India

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    B. S. Kholia

    2013-03-01

    Full Text Available A rare and little known, endemic fern Thelypteris kingii C.F.Reed was first described from a 19th Century collection from an unspecified locality in what was then "British Sikkim", now Darjeeling District, India. Recently a small population of the plant was rediscovered by the author from present-day Sikkim State. Herbarium records and field study reveal that this species is very rare and under great threat of extinction due to natural and man-made impact. This species is therefore little known to pteridologists and is readily confused with the similar, but common species, T. mollissima (Kunze N.Thapa as well as with another S. E. Asian species T. leptogrammoides (Ross. C.F. Reed due to nomenclatural similarities or being later homonymous. Although only known so far from India, and thus an endemic Indian species, its presence in Tibet and China etc. is probably to be expected. A brief history of its discovery, taxonomy, morphology, habitat and ecology is presented here to assist taxonomists and conservation biologists with its identification and conservation. It has been identified as Endangered and Globally Threatened and efforts have also been made by the present author to include it in the forthcoming volume of the Red Data Book of Indian plants.

  12. Plectranthias lamillai, a new Anthiine fish species (Perciformes, Serranidae from the Juan Fernández Archipelago, Chile

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    José Rodrigo Rojas M.

    1998-09-01

    Full Text Available Plectranthias lamillai new species, is described and illustrated as a new anthiine serranid fish from Alejandro Selkirk Island, the westernmost island of the Juan Fernández Archipelago, about 700 km west of Chile at 33°45´S, 80°51´W. The following combination of characters distinguishes it from all other serranids: dorsal fin rays X,16; principal caudal-fin rays 17 (8+9; pectoral-fin rays 16; gillrakers 28 (8+20; tubed lateral-line scales 40-41; 10 rows of scales on cheek; maxilla narrow and rounded; posterior margin of bony opercle with three spinous processes, the middle one largest; subopercle 2-6 small serrae; pseudobranch with 24 filaments; circumpeduncular scales 16; pelvic fin inserted beneath base of pectoral fin, the tip reaching a vertical through base of tenth dorsal-fin spine, falling short of the anus; a broad red bar from sixth dorsal-fin spine to base of fifth ray, extending to anus and above anal fin as a narrow band that widens on the peduncle and then bifurcates over the upper and lower margins of the caudal fin; rest of the caudal fin yellowish. Pectoral fins orange; pelvic and anal fins whitish.

  13. Ecological factors influencing growth of the endangered Hawaiian fern Marsilea villosa (Marsileaceae) and implications for conservation management.

    Science.gov (United States)

    Chau, Marian M; Reyes, Whitney R; Ranker, Tom A

    2013-08-01

    Conserving endangered plants is a complex task, and practitioners must often use a "triage" approach, addressing only immediate needs. Ecologists can improve this process by conducting sound science upon which to base management. Marsilea villosa is an endangered, endemic Hawaiian fern with seven remaining populations in ephemerally flooding drylands. Among its uncommon traits are long-lived sporocarps, requiring flood and drought to complete its sexual life cycle, and extensive vegetative growth. We conducted a 3-yr ecological field study, measuring percent cover of M. villosa and associated species, flooding depth, and canopy cover, to identify ecological factors with the greatest impact on M. villosa growth. Maximum flooding depth and canopy cover had strong positive relationships with M. villosa growth, and all plots with >50% threshold of either variable reached 100% cover of M. villosa by the end of the study. Interaction effects explained nuances of these relationships, including synergy between the two variables. Percent cover of nonnative functional groups (graminoids and nongraminoids) each had negative relationships with M. villosa growth, but interactions showed that nongraminoid cover was driven by particular species, and that time since flooding had greater influence on M. villosa growth than graminoid cover. We recommend planting reintroduced populations in flood-prone areas with moderate shade, experimental outplanting of native plants with M. villosa, and management of graminoids as a functional group, while nongraminoid management should be species-specific. These practices will promote self-sustaining populations and reduce the need for labor-intensive management.

  14. The Humanist Ideal of Peace in Pacification Accounts by the Chronicler Fernández de Oviedo

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    Vanina María Teglia

    2014-11-01

    Full Text Available This  paper  poses  that,  in  order  to  represent  the  first  Spanish  conquests  in  the Antilles, Gonzalo Fernández de Oviedo, within his Historia General y Natural de las Indias, takes certain official legal documents as models to guide and structure his account. Such documents are the royal ordinances and Palacios Rubios’ Requerimiento.  Consequently,  the  character’s speech  and  actions  are  marked  with  the  ideals  of  XVIth  century  humanist, Renaissance, and erasmist thought —peace, love-friendship  and the model of the prudent, moderate leaders— while a speech which seeks to legitimize the Spanish rules in the New World —while presenting it in terms of «pacification»— is being simultaneously unfolded. This whole discursive compound results in a plural, diverse and at times contradictory account, influenced and influential, and, above all, founding of some of the Utopian-imperial speech and imagery that were projected over the Americas and that constituted it.

  15. The rise of the Himalaya enforced the diversification of SE Asian ferns by altering the monsoon regimes.

    Science.gov (United States)

    Wang, Li; Schneider, Harald; Zhang, Xian-Chun; Xiang, Qiao-Ping

    2012-11-09

    The rise of high mountain chains is widely seen as one of the factors driving rapid diversification of land plants and the formation of biodiversity hotspots. Supporting evidence was reported for the impact of the rapid rise of the Andean mountains but this hypothesis has so far been less explored for the impact of the "roof of the world". The formation of the Himalaya, and especially the rise of the Qinghai-Tibetan Plateau in the recent 20 million years, altered the monsoon regimes that dominate the current climates of South East Asia. Here, we infer the hypothesis that the rise of Himalaya had a strong impact on the plant diversity in the biodiversity hotspot of the Southwest Chinese Mountains. Our analyses of the diversification pattern of the derived fern genus Lepisorus recovered evidence for changes in plant diversity that correlated with the strengthening of South East Asian monsoon. Southwest China or Southwest China and Japan was recovered as the putative area of origin of Lepisorus and enhancing monsoon regime were found to shape the early diversification of the genus as well as subsequent radiations during the late Miocene and Pliocene. We report new evidence for a coincidence of plant diversification and changes of the climate caused by the uplift of the Himalaya. These results are discussed in the context of the impact of incomplete taxon sampling, uncertainty of divergence time estimates, and limitations of current methods used to assess diversification rates.

  16. Structure of a shear-thickening polysaccharide extracted from the New Zealand black tree fern, Cyathea medullaris.

    Science.gov (United States)

    Wee, May S M; Matia-Merino, Lara; Carnachan, Susan M; Sims, Ian M; Goh, Kelvin K T

    2014-09-01

    A shear-thickening water-soluble polysaccharide was purified from mucilage extracted from the fronds of the New Zealand black tree fern (Cyathea medullaris or 'mamaku' in Māori) and its structure characterised. Constituent sugar analysis by three complementary methods, combined with linkage analysis (of carboxyl reduced samples) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR) revealed a glucuronomannan comprising a backbone of 4-linked methylesterified glucopyranosyl uronic acid and 2-linked mannopyranosyl residues, branched at O-3 of 45% and at both O-3 and O-4 of 53% of the mannopyranosyl residues with side chains likely comprising terminal xylopyranosyl, terminal galactopyranosyl, non-methylesterified terminal glucopyranosyl uronic acid and 3-linked glucopyranosyl uronic acid residues. The weight-average molecular weight of the purified polysaccharide was ∼1.9×10(6) Da as determined by size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS). The distinctive rheological properties of this polysaccharide are discussed in relation to its structure. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Pesca artesanal de cangrejo dorado (Chaceon chilensis en el archipiélago de Juan Fernández, Chile Artisanal fishing for golden crab (Chaceon chilensis off the Juan Fernández archipelago, Chile

    Directory of Open Access Journals (Sweden)

    Mauricio Ahumada

    2009-01-01

    Full Text Available Se describe la pesca artesanal de cangrejo dorado (Chaceon chilensis en las islas Robinson Crusoe y Santa Clara, en el archipiélago de Juan Fernández (Chile, desarrollada entre julio de 2005 y mayo de 2006. Se dan a conocer aspectos biológico-pesqueros relativos a esfuerzo y rendimientos de pesca, proporción sexual, así como los resultados de una evaluación directa de biomasa vulnerable mediante el método de area de influencia de las trampas. La extracción se efectuó fundamentalmente en el cuadrante NE de ambas islas, mediante botes de madera de 9,0 m de eslora. Se monitorearon 157 salidas de pesca y se capturaron 13.903 ejemplares, los cuales mayoritariamente fueron machos (97,5%. La CPUE promedio fue 16,7 ejemplares por trampa y de 13,5 ejemplares comerciales por trampa. A partir del muestreo sistemático, se detectó al recurso entre 300 y 1000 m de profundidad, con mayores rendimientos entre 400 y 500 m de profundidad (19,8 y 15,9 ejemplares por trampa. Se consideran y discuten dos escenarios de evaluación de stock para ejemplares de talla comercial en el area actualmente explotada (45,8 km , el primero estimó un radio efectivo para las trampas de 13,4 m (area de 564,1 m , con una biomasa vulnerable de 1.002 ton, equivalentes a 832.983 ejemplares, mientras que el segundo consideró un radio de 30,0 m con una biomasa vulnerable de 203 ton equivalente a 168.587 ejemplares.This work describes the artisanal golden crab (Chaceon chilensis fishery off Robinson Crusoe and Santa Clara islands in the Juan Fernández archipelago (Chile developed between July 2005 and May 2006. We report biological fishery aspects related to the físhing efforts and yields, the sexual proportion of the catch, and the results of a direct evaluation of the vulnerable biomass done using the trap area of influence method. The extraction was done mainly in the NE quadrant of both islands from wooden boats (9.0 m length. Monitoring was done during 157 f

  18. Isolation and Characterisation of a Proanthocyanidin With Antioxidative, Antibacterial and Anti-Cancer Properties from Fern Blechnum orientale

    Science.gov (United States)

    Lai, How-Yee; Lim, Yau-Yan; Kim, Kah-Hwi

    2017-01-01

    Background: Blechnum orientale Linn. (Blechnaceae), a fern, is traditionally used in the treatment of various ailments, such as skin diseases, stomach pain, urinary bladder complaints, and also as a female contraceptive. Previously, we reported a strong radical scavenging activity, antibacterial activity and cytotoxicity against HT29 colon cancer cells by aqueous extract of B. orientale. Objective: In this study, we attempted to isolate and identify the active compound from the aqueous extract of B. orientale. Materials and Methods: Aqueous extract of B. orientale was subjected to repeated MCI gel chromatography, Sephadex-LH-20, Chromatorex C18 and semi-preparative high performance liquid chromatography and was characterized using nuclear magnetic resonance and electrospray ionization mass-spectrometry spectroscopic methods. Antioxidant activity was determined using 2, 2-diphenyl-1-picrylhydrazyl radical scavenging assay. Antibacterial assays were conducted using disc diffusion whereas the minimum inhibitory concentration (MIC) and minimum bactericidal concentration were determined using the broth microdilution assay. Cytotoxicity was assessed using thiazolylblue tetrazoliumbromide. Results: A polymeric proanthocyanidin consisting of 2-12 epicatechin extension units and epigallocathecin terminal units linked at C4-C8 was elucidated. Bioactivity studies showed strong radical scavenging activity (IC50 = 5.6 ± 0.1 µg/mL), antibacterial activity (MIC = 31.3-62.5 µg/mL) against five gram-positive bacteria and selective cytotoxicity against HT29 colon cancer cells (IC50 = 7.0 ± 0.3 µg/mL). Conclusion: According to our results, the proanthocyanidin of B. orientale demonstrated its potential as a natural source of antioxidant with antibacterial and anti-cancer properties. SUMMARY A bioactive proanthocyanidin was isolated from the aqueous extract of medicinal fern Blechnum orientale Linn and the structure was elucidated using NMR and ESI-MS spectral studies

  19. Biostratigraphic evidence for dramatic Holocene uplift of Robinson Crusoe Island, Juan Fernández Ridge, SE Pacific Ocean

    Science.gov (United States)

    Sepúlveda, P.; Le Roux, J. P.; Lara, L. E.; Orozco, G.; Astudillo, V.

    2015-03-01

    Hotspot oceanic islands typically experience subsidence due to several processes related to migration of the oceanic plate away from the mantle plume and surface flexural loading. However, many other processes can interrupt subsidence, some of which may be associated with catastrophic events. A study of the biostratigraphy and sedimentology of Holocene deposits on Robinson Crusoe Island (RCI) on the Juan Fernández Ridge (JFR) indicated that dramatic uplift has occurred since 8000 years BP, at a rate of about 8.5mm yr-1. This is evidenced by supratidal flats with tepee structures and sand layers containing marine gastropods (mostly Nerita sp.) that are now exposed ca. 70 m a.s.l. The active hotspot is located 280 km further west and the last volcanic activity on RCI occurred at ca. 800 000 years BP. Long-term subsidence is evidenced by deep submerged marine abrasion terraces at RCI. As no direct evidence was found for the existence of a compensating bulge generated by the present hotspot upon which RCI would be situated, it must be concluded that subsidence in the wake of the mantle plume beneath the migrating plate was interrupted by very rapid uplift, but on a scale that did not fully compensate for the previous subsidence. This can be attributed to large-scale landslides followed by isostatic rebound, although this is only vaguely reflected in the low-resolution bathymetry of the area. To determine if this mechanism produced the uplift, a detailed bathymetric survey of the area will be required. If such a survey confirms this hypothesis, it may have implications for the short-term dynamics of vertical variations of oceanic edifices and their related effects on ecosystems and human population.

  20. Factors driving adaptive radiation in plants of oceanic islands: a case study from the Juan Fernández Archipelago.

    Science.gov (United States)

    Takayama, Koji; Crawford, Daniel J; López-Sepúlveda, Patricio; Greimler, Josef; Stuessy, Tod F

    2018-03-13

    Adaptive radiation is a common evolutionary phenomenon in oceanic islands. From one successful immigrant population, dispersal into different island environments and directional selection can rapidly yield a series of morphologically distinct species, each adapted to its own particular environment. Not all island immigrants, however, follow this evolutionary pathway. Others successfully arrive and establish viable populations, but they remain in the same ecological zone and only slowly diverge over millions of years. This transformational speciation, or anagenesis, is also common in oceanic archipelagos. The critical question is why do some groups radiate adaptively and others not? The Juan Fernández Islands contain 105 endemic taxa of angiosperms, 49% of which have originated by adaptive radiation (cladogenesis) and 51% by anagenesis, hence providing an opportunity to examine characteristics of taxa that have undergone both types of speciation in the same general island environment. Life form, dispersal mode, and total number of species in progenitors (genera) of endemic angiosperms in the archipelago were investigated from literature sources and compared with modes of speciation (cladogenesis vs. anagenesis). It is suggested that immigrants tending to undergo adaptive radiation are herbaceous perennial herbs, with leaky self-incompatible breeding systems, good intra-island dispersal capabilities, and flexible structural and physiological systems. Perhaps more importantly, the progenitors of adaptively radiated groups in islands are those that have already been successful in adaptations to different environments in source areas, and which have also undergone eco-geographic speciation. Evolutionary success via adaptive radiation in oceanic islands, therefore, is less a novel feature of island lineages but rather a continuation of tendency for successful adaptive speciation in lineages of continental source regions.

  1. Protection of immunocompromised mice from fungal infection with a thymus growth-stimulatory component from Selaginella involvens, a fern.

    Science.gov (United States)

    Gayathri, V; Asha, V V; John, J Anil; Subramoniam, A

    2011-06-01

    Recent studies have shown that the water extract of Selaginella involvens (Sw.) Spring, a wild fern, exhibits thymus growth-stimulatory activity in adult mice (reversal of involution of thymus) and remarkable anti-lipid peroxidation activity. Follow-up studies were carried out in the present study. Activity-guided isolation of the active component (AC) was carried out. The effect of AC on immune function was studied using fungal (Aspergillus fumigatus) challenge in cortisone-treated mice. The in vitro antifungal activity of AC was assayed using disc diffusion assay. In vitro and in vivo effect of AC on DNA synthesis in thymus was studied using (3)H-thymidine incorporation. In in vitro anti-lipid peroxidation, hydroxyl radical scavenging and inhibition of superoxide production were assayed. The active principle/component (AC) was isolated in a chromatographically pure form from the water extract of S. involvens. AC showed positive reaction to glycosides. AC possessed both thymus growth-stimulatory and antioxidant properties. It protected cortisone-treated mice from A. fumigatus challenge. It did not exhibit in vitro antifungal activity. Increased (3)H-thymidine incorporation was observed in the reticuloepithelium of thymus obtained from AC-treated mice. However, in vitro AC treatment to thymus for 5 h did not result in an increase in (3)H-thymidine incorporation. AC (named as Selagin), from S. involvens, could reverse involution of thymus to a large extent, exhibit remarkable antioxidant activity, and protect immunocompromised mice from fungal infection. Therefore, it is very promising for the development of a drug to ameliorate old age-related health problems and prolong lifespan.

  2. Applying Fishers' ecological knowledge to construct past and future lobster stocks in the Juan Fernández Archipelago, Chile.

    Science.gov (United States)

    Eddy, Tyler D; Gardner, Jonathan P A; Pérez-Matus, Alejandro

    2010-11-05

    Over-exploited fisheries are a common feature of the modern world and a range of solutions including area closures (marine reserves; MRs), effort reduction, gear changes, ecosystem-based management, incentives and co-management have been suggested as techniques to rebuild over-fished populations. Historic accounts of lobster (Jasus frontalis) on the Chilean Juan Fernández Archipelago indicate a high abundance at all depths (intertidal to approximately 165 m), but presently lobsters are found almost exclusively in deeper regions of their natural distribution. Fishers' ecological knowledge (FEK) tells a story of serial depletion in lobster abundance at fishing grounds located closest to the fishing port with an associated decline in catch per unit effort (CPUE) throughout recent history. We have re-constructed baselines of lobster biomass throughout human history on the archipelago using historic data, the fishery catch record and FEK to permit examination of the potential effects of MRs, effort reduction and co-management (stewardship of catch) to restore stocks. We employed a bioeconomic model using FEK, fishery catch and effort data, underwater survey information, predicted population growth and response to MR protection (no-take) to explore different management strategies and their trade-offs to restore stocks and improve catches. Our findings indicate that increased stewardship of catch coupled with 30% area closure (MR) provides the best option to reconstruct historic baselines. Based on model predictions, continued exploitation under the current management scheme is highly influenced by annual fluctuations and unsustainable. We propose a community-based co-management program to implement a MR in order to rebuild the lobster population while also providing conservation protection for marine species endemic to the Archipelago.

  3. PARACENTRAL ACUTE MIDDLE MACULOPATHY IN A PERIVENULAR FERN-LIKE DISTRIBUTION WITH EN FACE OPTICAL COHERENCE TOMOGRAPHY.

    Science.gov (United States)

    Garrity, Sean T; Tseng, Victoria L; Sarraf, David

    2017-11-22

    To report a case of central retinal vein occlusion resulting in a perivenular pattern of paracentral acute middle maculopathy lesions best identified with en face optical coherence tomography (OCT). Retrospective case report. Optos ultra-widefield fluorescein angiography, spectral domain OCT, en face OCT, and OCT angiography were performed. A 41-year-old man presented with decreased vision in the right eye for 2 weeks. Funduscopic examination of the affected right eye was notable for subtle retinal whitening in the macula, mild retinal venous dilation and tortuosity, and few scattered retinal dot and blot hemorrhages consistent with an acute central retinal vein occlusion. Widefield fluorescein angiography demonstrated delayed arterial and venous filling but no evidence of significant peripheral retinal vascular ischemia. En face OCT segmented at the inner nuclear layer illustrated a remarkable and precise perivenular distribution of fern-like paracentral acute middle maculopathy with periarterial sparing, whereas en face OCT segmented at the outer nuclear layer demonstrated florid cystoid macular edema. At 6-week follow-up, OCT demonstrated patchy areas of atrophic inner nuclear layer and spontaneous resolution of the cystoid macular edema. Optical coherence tomography angiography at the level of the deep capillary plexus illustrated remarkable flow reduction of the deep capillary plexus in mainly a perivenular distribution. The authors report a case of a central retinal vein occlusion with mild retinal findings associated with a remarkable perivenular pattern of paracentral acute middle maculopathy with en face OCT. Follow-up OCT angiography demonstrated significant flow reduction of the deep capillary plexus in a perivenular pattern. The perivenular pattern of paracentral acute middle maculopathy lesions with en face OCT can be an important finding suggestive of a central retinal vein occlusion.

  4. Plate tectonics and the origin of the Juan Fernández Ridge: analysis of bathymetry and magnetic patterns

    Directory of Open Access Journals (Sweden)

    Cristián Rodrigo

    2014-10-01

    Full Text Available Juan Fernández Ridge (JFR is a cα. 800 km long alignment of seamounts and islands which is thought to be fed by a deep mantle plume. JFR includes the Friday and Domingo seamounts in the western active edge close to the active hotspot, and the O'Higgins Seamount and Guyot at the eastern limit just in front of the Chile-Perú trench. Recent bathymetric (Global Topography and magnetic (EMAG-2 datasets were interpreted both qualitatively and quantitatively by means of 3D inverse modeling and 2D direct modeling for geometry and susceptibility, together with an interpretation of the synthetic anomalies related to the classical hypothesis of deep seafloor spreading. Topographic and magnetic patterns are used to understand the tectonic evolution and origin of the JFR, especially in the western segment. Results show a continuous corridor with a base at ~3900 m depth formed by four groups of seamounts/islands with a number of summits. The deep ocean floor is ~22 to ~37 Myr old and is younger to the south of the Challenger Fracture Zone that runs in a SW-NE direction. The magnetic pattern of the western JFR segment, which is different than the eastern one, has no correlation with bathymetry and does not present a common polarity nor fit with magnetic models for isolated bodies. This superposition of magnetic patterns indicates a role of the faults/fractures of the Nazca Plate. Geological evidence supports the hypothesis of a fixed mantle plume for the origin of JFR but our data suggest that tectonic processes play a role, thus fueling the global controversy about these competing processes.

  5. Applying Fishers' Ecological Knowledge to Construct Past and Future Lobster Stocks in the Juan Fernández Archipelago, Chile

    Science.gov (United States)

    Eddy, Tyler D.; Gardner, Jonathan P. A.; Pérez-Matus, Alejandro

    2010-01-01

    Over-exploited fisheries are a common feature of the modern world and a range of solutions including area closures (marine reserves; MRs), effort reduction, gear changes, ecosystem-based management, incentives and co-management have been suggested as techniques to rebuild over-fished populations. Historic accounts of lobster (Jasus frontalis) on the Chilean Juan Fernández Archipelago indicate a high abundance at all depths (intertidal to approximately 165 m), but presently lobsters are found almost exclusively in deeper regions of their natural distribution. Fishers' ecological knowledge (FEK) tells a story of serial depletion in lobster abundance at fishing grounds located closest to the fishing port with an associated decline in catch per unit effort (CPUE) throughout recent history. We have re-constructed baselines of lobster biomass throughout human history on the archipelago using historic data, the fishery catch record and FEK to permit examination of the potential effects of MRs, effort reduction and co-management (stewardship of catch) to restore stocks. We employed a bioeconomic model using FEK, fishery catch and effort data, underwater survey information, predicted population growth and response to MR protection (no-take) to explore different management strategies and their trade-offs to restore stocks and improve catches. Our findings indicate that increased stewardship of catch coupled with 30% area closure (MR) provides the best option to reconstruct historic baselines. Based on model predictions, continued exploitation under the current management scheme is highly influenced by annual fluctuations and unsustainable. We propose a community-based co-management program to implement a MR in order to rebuild the lobster population while also providing conservation protection for marine species endemic to the Archipelago. PMID:21079761

  6. The role of callose in guard-cell wall differentiation and stomatal pore formation in the fern Asplenium nidus.

    Science.gov (United States)

    Apostolakos, P; Livanos, P; Nikolakopoulou, T L; Galatis, B

    2009-12-01

    The pattern of callose deposition was followed in developing stomata of the fern Asplenium nidus to investigate the role of this polysaccharide in guard cell (GC) wall differentiation and stomatal pore formation. Callose was localized by aniline blue staining and immunolabelling using an antibody against (1 --> 3)-beta-d-glucan. The study was carried out in stomata of untreated material as well as of material treated with: (1) 2-deoxy-d-glucose (2-DDG) or tunicamycin, which inhibit callose synthesis; (2) coumarin or 2,6-dichlorobenzonitrile (dichlobenil), which block cellulose synthesis; (3) cyclopiazonic acid (CPA), which disturbs cytoplasmic Ca(2+) homeostasis; and (d) cytochalasin B or oryzalin, which disintegrate actin filaments and microtubules, respectively. In post-cytokinetic stomata significant amounts of callose persisted in the nascent ventral wall. Callose then began degrading from the mid-region of the ventral wall towards its periphery, a process which kept pace with the formation of an 'internal stomatal pore' by local separation of the partner plasmalemmata. In differentiating GCs, callose was consistently localized in the developing cell-wall thickenings. In 2-DDG-, tunicamycin- and CPA-affected stomata, callose deposition and internal stomatal pore formation were inhibited. The affected ventral walls and GC wall thickenings contained membranous elements. Stomata recovering from the above treatments formed a stomatal pore by a mechanism different from that in untreated stomata. After coumarin or dichlobenil treatment, callose was retained in the nascent ventral wall for longer than in control stomata, while internal stomatal pore formation was blocked. Actin filament disintegration inhibited internal stomatal pore formation, without any effect on callose deposition. In A. nidus stomata the time and pattern of callose deposition and degradation play an essential role in internal stomatal pore formation, and callose participates in deposition of the

  7. Global phylogeny and biogeography of the fern genus Ctenitis (Dryopteridaceae), with a focus on the Indian Ocean region.

    Science.gov (United States)

    Hennequin, Sabine; Rouhan, Germinal; Salino, Alexandre; Duan, Yi-Fan; Lepeigneux, Marie-Capucine; Guillou, Marguerite; Ansell, Steve; Almeida, Thaís Elias; Zhang, Li-Bing; Schneider, Harald

    2017-07-01

    The diverse and pantropical genus Ctenitis, in the Dryopteridaceae, has been largely ignored in phylogenetic studies until now. In this study, we fill in this gap by reconstructing the first comprehensive phylogeny of the genus including 53 species currently recognized in the genus Ctenitis, among which seven species formerly were assigned to the genus Pseudotectaria and one to Heterogonium. Special emphasis was given to the sampling of species occurring in the African-Indian Ocean region. The presented results include reconstruction of a biogeographic scenario based on estimated divergence times and ancestral area reconstruction. Our findings confirm the inclusion, within Ctenitis, of the Indian Ocean species formerly placed in Pseudotectaria and Heterogonium. The crown group divergence was estimated to date back to the Oligocene or Early Miocene. The biogeographical scenario indicates an initial divergence of the Asian-Pacific ranges and the neotropical ranges, and a subsequent colonization of the Afro-Madagascan region by a lineage with neotropical ancestors. The Afro-Madagascan lineage splits into a lineage endemic to the Mascarene islands and a lineage occurring in Madagascar, the Comoros and Africa. The range expansion towards Africa and Madagascar was estimated to date back to the late Miocene, whereas the estimated ages for the onset of the diversification of the Mascarene diversity is consistent with the ages of these young, volcanic islands. The absence of any extant species of Ctenitis with a multi-continental distribution range and the rarity of inter-island dispersal and speciation in the Indian Ocean region suggest a limited contribution of long distance dispersal to the biogeographical history of this fern genus, versus a high contribution of local speciation. Copyright © 2017. Published by Elsevier Inc.

  8. The Relationship Between Tear Ferning Patterns and Non-invasive Tear Break-up Time in Normal Asian Population.

    Science.gov (United States)

    Sharanjeet-Kaur; Ho, Chien Yee; Mutalib, Haliza Abdul; Ghazali, Ahmad Rohi

    2016-01-01

    To investigate the relationship between tear ferning patterns (TFP) and non-invasive tear break-up time (NIBUT) in normal Asian subjects. One hundred and forty-five adults with no ocular surface disorders were recruited. TFP and NIBUT were determined. Tears were collected using a capillary tube and allowed to air dry at room temperature for 10min. TFP was later observed using a light microscope and classified according to Rolando's classification. Measurement for NIBUT was obtained using a Tearscope with the slit lamp magnification. It was found that there is no significant difference between gender in TFP (Z=-1.77, P>.05) and NIBUT (Z=-1.475, P>.05). There is also no significant difference between Malay, Chinese, Indian, and other races in TFP, (H(3)=4.85, P>.05) and NIBUT (H(3)=2.18, P>.05). However, there is a significant difference between age groups of 20-29, 30-39, 40-49,and 50-60 years old in both TFP (H(3)=28.25, P<.01) and NIBUT (H(3)=36.50, P<.001). Spearman's correlation showed there was a significant relationship between TFP and NIBUT (r=-0.55, P<.001), age and NIBUT (r=-0.50, P<.001), age and TFP (r=0.41, P<.001), McMonnies score and NIBUT (r=-0.40, P<.001), McMonnies score and TFP (r=0.31, P<.001), as well as age and McMonnies score (r=0.52, P<.001). TFP and NIBUT was age dependent but not gender and race dependent. Older subjects had higher grade of TFP and McMonnies questionnaire score but lower NIBUT value. TFP and NIBUT can be used to assess the tear film quality. Copyright © 2015 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  9. Imaging of metal bioaccumulation in Hay-scented fern (Dennstaedtia punctilobula) rhizomes growing on contaminated soils by laser ablation ICP-MS

    International Nuclear Information System (INIS)

    Koelmel, Jeremy; Amarasiriwardena, Dulasiri

    2012-01-01

    Understanding Pb removal from the translocation stream is vital to engineering Pb hyperaccumulation in above ground organs, which would enhance the economic feasibility of Pb phytoextraction technologies. We investigated Cu, Pb, Sb and Zn distributions in Hay-scented fern (Dennstaedtia punctilobula) rhizomes on shooting range soils by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), analyzing digested rhizomes, stems, and fronds using ICP-MS. Nutrients Cu and Zn concentrated in fronds while toxic elements Pb and Sb did not, showing potential Pb and Sb sequestration in the rhizome. Frond and rhizome concentration of Pb was 0.17 ± 0.10% and 0.32 ± 0.21% of dry biomass, respectively. The 208 Pb/ 13 C and 121 Sb/ 13 C determined by LA-ICP-MS increased from inner sclerotic cortex to the epidermis, while Pb concentrated in the starchy cortex only in contaminated sites. These results suggest that concentration dependent bioaccumulation in the rhizome outer cortex removes Pb from the vascular transport stream. - Highlights: ► Bioimaged Cu, Pb, Sb, Zn across fern rhizomes from shooting ranges using LA-ICP-MS. ► Pb levels were highest in the outer starchy cortex. ► Pb seemed to displace nutrients Cu and Zn in contaminated site rhizomes. ► [Pb] and [Sb] were correlated across organs suggesting similar transport factors. - Using LA-ICP-MS we determined elemental distributions in Hay-scented fern rhizomes including concentration dependent Pb sequestration patterns in the outer cortex.

  10. Mesobathic chondrichthyes of the Juan Fernández seamounts: are they different from those of the central Chilean continental slope?

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2008-03-01

    Full Text Available We compared the geographic distribution of groups of chondrychthid fishes of two physically proximal, although geographically different, regions that include the Juan Fernández seamounts and the central Chilean continental slope, both sampled at mesopelagic and mesobenthonic depths. The ridge is in the Nazca Plate, while the slope region in on the South American Plate, and is closer to the South American continent. We found six species of Chondrichthyes for the seamounts (four orders, four families. The slope sampling produced ten species of Chondrichthyes, of which Torpedo tremens De Buen 1959, was the only species in common with the Juan Fernández area. There are clear differences between the Chondrichthyes of the two regions. These fisheries require adequate administrative modes. Rev. Biol. Trop. 56 (1: 181-190. Epub 2008 March 31.Se realizó un estudio de distribución geográfica comparativa entre conjuntos de peces condrictios de dos sectores geográficamente cercanos, pero geológicamente distintos, el sector este de la cordillera sumergida de Juan Fernández y el talud continental de Chile central, a profundidades mesopelágicas y mesobentónicas. La cordillera está sobre la placa de Nazca, el talud en la Sudamericana. Comparamos familias, géneros y especies, mediante el índice de Jaccard. Hay seis especies de condrictios en los montes submarinos (cuatro órdenes y cuatro familias. El talud tiene diez especies, y únicamente comparte con la cordillera a Torpedo tremens De Buen 1959. Estos condrictios requieren modos administrativo-pesqueros adecuados.

  11. Identification of up-regulated genes from the metal-hyperaccumulator aquatic fern Salvinia minima Baker, in response to lead exposure.

    Science.gov (United States)

    Leal-Alvarado, Daniel A; Martínez-Hernández, A; Calderón-Vázquez, C L; Uh-Ramos, D; Fuentes, G; Ramírez-Prado, J H; Sáenz-Carbonell, L; Santamaría, J M

    2017-12-01

    Lead (Pb) is one of the most serious environmental pollutants. The aquatic fern Salvinia minima Baker is capable to hyper-accumulate Pb in their tissues. However, the molecular mechanisms involved in its Pb accumulation and tolerance capacity are not fully understood. In order to investigate the molecular mechanisms that are activated by S. minima in response to Pb, we constructed a suppression subtractive hybridization library (SSH) in response to an exposure to 40μM of Pb(NO 3 ) 2 for 12h. 365 lead-related differentially expressed sequences tags (ESTs) were isolated and sequenced. Among these ESTs, 143 unique cDNA (97 were registered at the GenBank and 46 ESTs were not registered, because they did not meet the GenBank conditions). Those ESTs were identified and classified into 3 groups according to Blast2GO. In terms of metabolic pathways, they were grouped into 29 KEGG pathways. Among the ESTs, we identified some that might be part of the mechanism that this fern may have to deal with this metal, including abiotic-stress-related transcription factors, some that might be involved in tolerance mechanisms such as ROS scavenging, membrane protection, and those of cell homeostasis recovery. To validate the SSH library, 4 genes were randomly selected from the library and analyzed by qRT-PCR. These 4 genes were transcriptionally up-regulated in response to lead in at least one of the two tested tissues (roots and leaves). The present library is one of the few genomics approaches to study the response to metal stress in an aquatic fern, representing novel molecular information and tools to understand the molecular physiology of its Pb tolerance and hyperaccumulation capacity. Further research is required to elucidate the functions of the lead-induced genes that remain classified as unknown, to perhaps reveal novel molecular mechanisms of Pb tolerance and accumulation capacity in aquatic plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. First Harvestman Record for the Juan Fernández Archipelago, Chile, with Morphological Notes on Acropsopilio chilensis (Opiliones: Caddidae: Acroposopilioninae).

    Science.gov (United States)

    Pérez-González, Abel; Ramírez, Martín J; Soto, Eduardo M; Pizarro-Araya, Jaime

    2014-08-15

    Acropsopilio chilensis Silvestri, 1904 (Eupnoi: Caddidae: Acropsopilioninae), is recorded for Robinson Crusoe Island, Chile. This is the first harvestman species recorded for the Juan Fernández Archipelago and also the first extra-continental record for this species. During the comparison with continental co-specific specimens, some previously unknown, remarkable morphological characteristics were discovered, among them: the absence of ovipositor seminal receptacles and tracheal system, small and probably imperforate spiracles and the presence of a subdistal spiny structure, maybe a stylus, in the major branch of the penis. 

  13. Emilio \\'Indio\\' Fernández: conciliação de classes e política social no México dos anos 1940

    OpenAIRE

    Aline Boldrin Beltrame

    2009-01-01

    Este trabalho tem por objetivo analisar os filmes Pueblerina, Flor Silvestre e Enamorada do diretor Emílio Fernández, consagrado cineasta mexicano. Estes são considerados os mais importantes filmes desse diretor, todos realizados na década de 1940, ele um dos mais expressivos realizadores da história do cinema mexicano. As questões político-sociais, a violência são exploradas indiretamente nesses trabalhos e evidenciar este fato nosso principal ponto de conflito com a critica de cinema tradic...

  14. Ciclo anual de la clorofila-α satelital en el archipiélago de Juan Fernández (33°S), Chile

    OpenAIRE

    Andrade,Isabel; Hormazabal,Samuel E; Correa-Ramirez,Marco A

    2012-01-01

    La variabilidad espacial y temporal del ciclo anual de la clorofila-α en el archipiélago de Juan Fernández se analiza usando ocho anos de datos satelitales de clorofila-α, viento, corrientes y nivel del mar. Este archipiélago está conformado por tres islas: Robinson Crusoe-Santa Clara (RC-SC) y Alejandro Selkirk (AS). Las islas RC-SC se encuentran en una región de alta energía cinética y mayores concentraciones de clorofila-α definida como Zona de Transición Costera, en cambio ...

  15. Celestino Fernández de la Vega e as súas publicacións no diario lucense "El Progreso"

    OpenAIRE

    Arias Gómez, Noelia

    2017-01-01

    Celestino Fernández de la Vega (1914-1986) destaca pola súa gran implicación coa cultura e coa cidade de Lugo. A pesares do seu labor como tradutor, ensaísta, filósofo, promotor dos faladoiros e de actividades e institucións tanto culturais como deportivas e gran articulista en El Progreso e outros xornais, é unha personalidade pouco coñecida e mencionada nas aulas. O estudo da súa faceta articulista como colaborador do xornal El Progreso, a menos coñecida, pretende afondar no coñeceme...

  16. “Historias olvidadas en las cunetas”. Entrevista con Adriana Fernández, integrante de la Plataforma Argentina de Apoyo a la Querella contra los Crímenes del Franquismo

    Directory of Open Access Journals (Sweden)

    Mariela Sánchez

    2013-12-01

    Full Text Available The exhumation process of the remains of Antonio Fernández, a young man killed in 1936 in Spain, is the theme in Las cunetas, by Bodo Marks and Shelina Islam. A presentation and screening experience of the documentary has led to an interview with Adriana Fernández, Antonio’s granddaughter and a member of the Argentine Support Complaint Platform against Crimes of Francoism. Her responses, in dialogue with the material above mentioned, constitute a story that combines the verbal and the visual experience of a transatlantic quest for truth and justice

  17. Island mass effect in the Juan Fernández Archipelago (33°S), Southeastern Pacific

    Science.gov (United States)

    Andrade, Isabel; Sangrà, Pablo; Hormazabal, Samuel; Correa-Ramirez, Marco

    2014-02-01

    Spatial and temporal variability of the island mass effect (IME; defined as local increases of phytoplankton associated with the presence of islands) at the Juan Fernández Archipelago (JFA) is analyzed using chlorophyll-a (Chl-a) satellite data, altimetry, sea surface temperature, wind, geostrophic currents and net heat flux over a ten year period (2002-2012). The the JFA islands (Robinson Crusoe-Santa Clara (RC-SC) and Alejandro Selkirk (AS)) present wakes with significant Chl-a increases, mainly during spring time. These wakes can reach Chl-a values of one order of magnitude higher (~1 mg m-3) than the surrounding oligotrophic waters (<0.1 mg m-3). The wakes are similar to von Kármán vortex streets which have been used to explain the impact of IME on Chl-a increases in numerical models. The wakes are formed from a high productivity area in the lee of the island, extending to the oceanic region as high Chl-a patches associated with submesoscale eddies that are detached from the islands and connected by less-productive zones. This pattern coincides with previous models that predict the effects of island-generated flow perturbations on biological production variability. The IME is a recurrent feature of islands that has even been observed in decadal average fields. In such average fields, the Chl-a values in RC-SC and AS islands can exceed values found in a Control Zone (a zone without islands) by ~50% and 30%, respectively. Seasonal and interannual variability reveals that, as a consequence of the IME, the winter Chl-a maximum associated with the development of winter convection and mesoscale eddies that propagate from the continental zone, promote that the Chl-a maximum extends towards spring. The IME has an impact on the island on both a local as well as a more regional scale that affects an area of ~40,000 km2 (1°Latitude×4°Longitude) centered on the islands. The transport of high productivity patches associated with submesoscale eddies may be responsible

  18. Ability of the aquatic fern Azolla to remove chemical oxygen demand and polyphenols from olive mill wastewater

    Directory of Open Access Journals (Sweden)

    Sacchi, Angelo

    2007-03-01

    Full Text Available We investigated the biofiltration ability of the aquatic fern Azolla to remove polyphenols and chemical oxygen demand (COD from olive mill wastewater (OMWw collected from the traditional (TS and continuous (CS extraction systems. Azolla biomass was packed into five sequential Imhoff cones and five sequential columns. In both experiments, the filtrates collected from the 5th biofilter showed a decrease in polyphenol contents: from 7650 mg l–1 to 3610 mg l–1 in TS OMWw and from 3852 mg l–1 to 1351 mg l–1 in CS OMWw. The COD contents decreased from 110200 mg L–1 to 52400 mg L–1 in TS OMWw and from 41600 mg L–1 to 2300 mg L–1 in CS OMWw. A 5:1 OMWw to Azolla-fresh-weight ratio was optimal for both polyphenol and COD removal. The biofiltration ability of alfalfa was compared with that of Azolla, but the treatment with alfalfa did not result in the reduction of COD or polyphenols.La eficacia del helecho de agua azolla para eliminar polifenoles y reducir la demanda química de oxígeno (DQO de los alpechines obtenidos en el proceso de obtención tradicional y continuo del aceite de oliva, fue investigado mediante ensayos de filtración. Cinco conos secuenciales de Imhoff y cinco columnas secuenciales se rellenaron de biomasa de Azolla. En ambos experimentos, el filtrado procedente de la quinta extracción mostró una disminución en el contenido de polifenoles de 7650 mg L–1 a 3610 mg L–1en el alpechín obtenido mediante el sistema tradicional y de 3852 mg L–1 a 1351 mg L–1en el alpechín del sistema continuo. La demanda química de oxígeno del alpechín del sistema tradicional disminuyó de 110200 mg L–1 a 52400 mg L–1 en y de 41600 mg L–1a 2300 mg L–1en el procedente del sistema continuo. Una proporción en peso 5:1 de alpechín: Azolla fue la óptima tanto para la reducción de los polifenoles como para la de la DQO. La eficiencia del tratamiento biológico con alfalfa se comparó con la obtenida con Azolla. Los

  19. Growth dynamics of fine roots in a coniferous fern forest site close to Forsmark in the central part of Sweden

    International Nuclear Information System (INIS)

    Persson, Hans; Stadenberg, Ingela

    2007-12-01

    The seasonal growth dynamics of live and dead roots for trees and the field layer species (g/m 2 , varying diameter fractions) and live/dead ratios were analysed at a fresh/moist coniferous fern forest site close to the nuclear power plant at Forsmark in the central eastern parts of Sweden. The changes in depth distribution of fine roots were observed at depth intervals of the top humus horizon down to 40 cm in the mineral soil profile. The bulk of living fine roots of trees ( 2 . The total quantity of fine roots (live + dead) amounted to 543, 434, 314 and 546 g/m 2 . Considerable quantities of fine roots (< 1 mm in diameter) were attributed to field-layer species (about 18% of the total biomass during the whole period of investigation). The turnover rate (the rate of construction of new roots) for tree fine roots < 1 mm in diameter amounted to at least the size of the average fine-root biomass. Our methods of estimating fine-root production and mortality, involved periodic measurements of live and dead dry weight of the fine roots from sequential core samples of the forest soil. The collected data give a proper and instant measure of the spatial and temporal distribution of fine roots in the undisturbed soil-profile. Data from other fine-root investigations suggest turnover rates in agreement with our present findings. Differences between root growth and turnover should be expected between trees of different age, tree species and different forest sites, but also between different years. Substantial variations in fine-root biomass, necromass and live/dead ratios are found in different forest sites. Correct methods for estimating the amount of live and dead fine-roots in the soil at regular time intervals are essential for any calculation of fine-root turnover. Definition of root vitality differs in literature, making it difficult to compare results from different root investigators. Our investigation clarifies the importance of using distinct morphological criteria

  20. Distribution and dynamics of two ferns: Dennstaedtia punctilobula (Dennstaedtiaceae) and Thelypteris noveboracensis (Thelypteridaceae) in a Northeast mixed hardwoods-hemlock forest.

    Science.gov (United States)

    Hill, J D; Silander, J A

    2001-05-01

    Dennstaedtia punctilobula and Thelypteris noveboracensis are two native species that often arrest forest succession and reduce understory diversity. As part of a project to examine the feedback between forest understory and canopy dynamics, we studied the patterns of distribution and dynamics of these two fern species in an oak-transition hardwoods-hemlock forest. Dennstaedtia was least abundant under shade-tolerant tree species and most abundant in small (1-2 trees) canopy gaps, but did not show any distinct patterns across the sampled moisture regime. The light response was verified using light manipulation experiments and examination of plant size-abundance patterns across light environments. Thelypteris tended to be most prevalent under maple canopies and appeared to be more sensitive to soil moisture regime being restricted to more mesic sites than Dennstaedtia. Seasonal and year-to-year changes in abundance of established clones of both fern species were small, suggesting that once established, both species can maintain a strong hold on a site. Further work on the niche requirements of the two species is warranted, but any event that maintains or promotes canopy openness (tree death by disease or windthrow, forest harvesting, or the elimination of a shrub layer by browsing) will promote persistence of Dennstaedtia.

  1. Bracken fern poisoning to cattle raised in Parana State, Brazil/ A intoxicação por samambaia em bovinos criados no Estado do Paraná

    Directory of Open Access Journals (Sweden)

    Wilmar Sachetin Marçal

    2003-05-01

    Full Text Available The author presents a revision about bracken fern (Pteridium aquilinum, L. Kuhn, in cattle, raised in the state of the Paraná. This toxic plant represents huge damages to the creators in the state and is being disseminated quickly, becoming the toxic plant of negative consequences to the health of the cattle. The author also describe climatic and environmental conditions about proliferation of Bracken fern in the Parana state, Brazil.O autor apresenta uma revisão sobre a intoxicação por samambaia (Pteridium aquilinum, L. Kuhn, em bovinos, criados no estado do Paraná. Esta planta representa enormes prejuízos aos criadores no estado e está se disseminando rapidamente, tornando-se a planta tóxica de maiores conseqüências negativas à saúde dos bovinos, havendo condições ambientais e climáticas favorecedoras de sua proliferação nas pastagens paranaenses.

  2. Paleomycology of the Princeton Chert. III. Dictyosporic microfungi, Monodictysporites princetonensis gen. et sp. nov., associated with decayed rhizomes of an Eocene semi-aquatic fern.

    Science.gov (United States)

    Klymiuk, Ashley A

    2016-09-01

    This study builds on previous investigations of paleomycological diversity within permineralized plants of a significant Eocene paleobotanical locality, the Princeton Chert. The fungal body fossils described here occur in decayed rhizomes of the extinct semi-aquatic fern Dennstaedtiopsis aerenchymata Fungi include vegetative hyphae throughout the plant tissue, as well as a dense assemblage of >100 dematiaceous spores. The spores occur in a discrete zone surrounding two extraneous rootlets of other plants, which penetrated the fern tissue post-mortem. Spores are obovoid and muriform, composed of 8-12 cells with constricted septa and produced from hyaline or slightly pigmented hyphae. The spores are morphologically similar to both asexual reproductive dictyospores of phylogenetically disparate microfungi attributed to the morphogenus Monodictys and perennating dictyochlamydospores that occur in the anamorph genus Phoma In addition to expanding the early Eocene fossil record for Ascomycota, these specimens also provide new insight into the rapidity of initial phases of the fossilization process in this important paleobotanical locality. © 2016 by The Mycological Society of America.

  3. Role of bracken fern (Pteridium aquilinum (L. Kuhn in animal and human heath/ Toxicidade da samambaia (Pteridium aquilinum (L. Kuhn para a saúde animal e humana

    Directory of Open Access Journals (Sweden)

    Ana Paula F. R. L. Bracarense

    2004-05-01

    Full Text Available The article reviews some of the main characteristics of Pteridium aquilinum (bracken fern and the main consequences of its ingestion by livestock animals, laboratory animals and man. Ptaquiloside is considered the main responsible for the neoplasias in these cases. Three main routes may lead to human exposure to the toxic effects of bracken fern: eating the plant, physical contact (inhalation of the spores or ingestion of contaminated water and ingestion of raw milk from affected animals.O artigo revisa algumas das principais características da planta Pteridium aquilinum (samambaia bem como as conseqüências da sua ingestão por animais de produção, animais de laboratório e pelo próprio homem. O composto ptaquilosídeo encontrado na planta é considerado atualmente o principal responsável pelo aparecimento de neoplasias. No homem, existem três maneiras pelo qual este pode ser intoxicado: ingestão da planta, contato físico (inalação dos esporos ou ingestão de água contaminada e ingestão de leite cru de animais que ingeriram a planta.

  4. LA PALABRA DIBUJADA. ANTONIO FERNÁNDEZ-ALBA, PRIMER Y ÚLTIMO MAESTRO / The drawn word. Antonio Fernández-Alba, first and last master

    Directory of Open Access Journals (Sweden)

    Juan Luis Trillo de Leyva

    2015-05-01

    Full Text Available Távora y Fernández-Alba son figuras de referencia ineludible para quienes quieran hoy investigar el origen contemporáneo de la arquitectura peninsular y, sobre todo, de sus escuelas. Alba fue siempre una guía para los que abordamos una enseñanza alejados del aura que acompañaba a los grandes arquitectos madrileños y barceloneses. Su experimentación didáctica alteró la trayectoria de las escuelas de arquitectura españolas. Introdujo la cultura contemporánea en la universidad como si se tratara de una segunda naturaleza, de un nuevo estrato territorial de los proyectos, manteniendo al hombre como objeto central y destinatario de todo proceso proyectual. En época de virtualidad y representación automatizada, nada más adecuado que la revisión de los dibujos del maestro Fernández-Alba. Dibujos que requieren ser proyectados, pensados, antes que ejecutados, “proyectos de proyectos”, una especie de tautología que rige la mente del poeta en su continua reducción, compresión o destilación, gota a gota, del mundo real, del universo y la palabra.

  5. New additions to the introduced flora of the Juan Fernández Islands: origin, distribution, life history traits, and potential of invasion Nuevas adiciones a la flora introducida de las Islas Juan Fernández: origen, distribución, rasgos de historia de vida y potencial de invasión

    Directory of Open Access Journals (Sweden)

    JAIME G. CUEVAS

    2004-09-01

    Full Text Available Oceanic islands, such as Juan Fernández in Chile, are the home for particular biotas that have evolved in isolation over a long period. The anthropogenic introduction of allochtonous plants is one of many problems for the conservation of endemic elements. In this paper, we present the new additions to the introduced flora of the Juan Fernández Islands, adding some comments about their life form, origin, morphological characteristics, ecology, distribution, abundance, and their potential of invasion. We cited 27 new species, 12 new genera, and three new families for the Juan Fernández flora (Amaryllidaceae, Commelinaceae and Violaceae. Most genera belonged to Asteraceae (seven species. Fifty-nine percent of taxa were perennial herbs, followed by annual or biennial herbs. Wind was the main vector of propagule dispersal (42 %, followed by vegetative dispersal (23 %. Fifty-two percent of the species were weeds and 44 % were plants with dual behaviour: garden-weed plant. Eurasia was the most frequent area of plant origin (70 %. Ninety-four percent of the taxa with known geographic range are in the V Region of mainland Chile, which is the main region of export of plants and materials to the archipelago, suggesting that this may have been the immediate origin of these introductions. Sixty-three percent of the species were only found in the San Juan Bautista urban area, while the remaining taxa were also (22 % or exclusively (15 % found in other places of the main island (Robinson Crusoe. Sixteen species (59 % are considered as noxious weeds in Juan Fernández or elsewhere, and they should be a focus of attention and, eventually, control. Summing our findings to previous lists of introduced taxa, we obtained 260 non-native taxa in Juan Fernández. This number is greater than the native taxa (211, which demonstrate how the human intentional and non-intentional action can dramatically change the floristic composition of an oceanic archipelago. We

  6. Alonso, Luis Enrique y Fernández Rodríguez, Carlos Jesús (2013). Los discursos del presente. Un análisis de los imaginarios sociales contemporáneos

    OpenAIRE

    Barbeta Viñas, Marc

    2014-01-01

    Review of the work written by Luis Enrique Alonso and Carlos Jesús Fernández Rodríguez apeared in 2013, Los discursos del presente. Un análisis de los imaginarios sociales contemporáneos. Madrid: Siglo XXI, 317 p. ISBN 978-84-323-1650-0

  7. Cultivo de Cattleya Lindley (Orchidaceae em substratos alternativos ao xaxim = Alternative substrates for Cattleya (Orchidaceae cultivation to substitute the tree fern fiber

    Directory of Open Access Journals (Sweden)

    Jorge Kaoro Yamakami

    2006-10-01

    Full Text Available Este trabalho teve como objetivo avaliar substratos alternativos ao xaxim no cultivo de um híbrido de Cattleya Lindley. Os substratos avaliados foram: xaxim; fibra de coco; casca de pínus + casca de arroz carbonizada (1:1v/v; casca de pínus+casca de arroz carbonizada (2:1v/v; casca de pínus+casca de arroz carbonizada (1:2v/v; casca de pínus e casca de arroz carbonizada. As mudas foram cultivadas em vasos de polipropileno, permanecendo em viveiro com 70% de luminosidade Os parâmetros avaliados um ano após o início do experimento foram: massa de matéria fresca total, altura da parte aérea, comprimento do pseudobulbo, comprimento da maior raiz, número de raízes, número de brotos, número de flores, pH e condutividade elétrica. O substrato constituído de fibra de coco proporcionou bons resultados, podendo ser considerado alternativo ao xaxim no cultivo deCattleya.The objective of this study was to evaluate alternative substrates tosubstitute tree fern fiber for cultivation of hybrids from the Cattleya species. Seedlings were cultivated in polypropylene vases, kept in screen shadowed nursery by a 70% of lighting. The following substrates were evaluated: tree fern fibers; coconut fiber; pinus bark+carbonized rice hull (1:1 v/v; pinus bark+carbonized rice hull (2:1 v/v; pinus bark+carbonized rice hull (1:2 v/v; pinus bark and carbonized rice hull. One year after the experiment, the followingparameters were evaluated: fresh matter mass, aerial part height, pseudobulb length, greater root length, number of buds, number of flowers, pH and electric conductivity. The substrate composed of coconut fiber showed better results, and can be used as the alternative substrate to tree fern fiber in the cultivation of Cattleya.

  8. Analog Modeling of the Juan Fernández Ridge, Central Chile, and Implications for Flat-Slab Subduction Dynamics

    Science.gov (United States)

    Woodell, D.; Anderson, M. L.

    2009-12-01

    This study compares the strain experienced by the subducting lithosphere in analog models to the strain recorded by earthquakes in the subduction zone that includes the Juan Fernández Ridge (JFR), near 33 S, 73 W, off the coast of central Chile. The JFR is an aseismic hot spot ridge that has a thickened oceanic crust. The overthickened crust reduces the total density of the slab when compared to the surrounding slab areas, and thus increases the buoyancy of the subducting Nazca plate at this particular location. It is hypothesized that the Nazca plate experiences “flat-slab” subduction at the JFR subduction zone due to this buoyancy. Brudzinski and Chen (2005) argue that, due to the poorly aligned direction of maximum extension (T axes) for earthquakes in the subducting slab in flat-slab subduction zones, the theory of “slab pull” may not be valid for flat-slab subduction zones, and there must be other forces at work. However, Anderson et al. (2007) develop new, more precise slab contours from newly determined earthquake locations and use these contours to qualitatively compare the earthquake data to slab dip directions and thus expected slab-pull directions. They conclude that T axes are parallel to slab dip, and thus slab pull is the only force necessary for explaining the T axis direction. In this study, we quantitatively compare extension produced in analog "flat-slab" models in the laboratory to T axes from the Anderson et al. (2007) study, extending and further testing their idea. Several materials comprise the analog models. Light corn syrup represents the asthenosphere, while silicon putty represents the lithosphere. Recreating the dynamics of the buoyant JFR necessitates two different densities of silly putty: a denser one for the bulk of the slab, and a less dense one for the buoyant ridge. Shallow circular indentations (strain ellipses) on the slab facilitate recording of the strain in the subducting slab. Video and still pictures record each

  9. Alterações anátomo-histopatológicas em ratos submetidos à dieta com extrato de broto de samambaia (Pteridium aquilinum var. arachnoideum de dois municípios do estado do Paraná Macroscopic and microscopic changes in rats fed on a bracken fern diet (Pteridium aquilinum var. arachnoideum from different regions of Parana State, Brazil

    Directory of Open Access Journals (Sweden)

    G.D. Cruz

    2005-06-01

    Full Text Available The carcinogenicity of bracken fern harvest from two regions of Paraná State to induce hematury in rats was studied. In order to do that, 33 Wistar rats were divided in three groups. Groups I and II received an aqueous extract of bracken fern from Londrina-PR or Ibaiti-PR, respectively, in drinking water for 60 days. Group III, control group, received regular plain water with no bracken fern. After 15 months, euthanasia was performed in all animals and samples were collected for histology examination. Histologic analysis revealed that two animals of Group II had ileal adenocarcinoma and soft tissue fibroma of leg.

  10. Innovation in hydroelectric power plant design in early twentieth century. Casto Fernández-Shaw's Engineering Architecture in La Jándula dam

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    A. B. Berrocal Menárguez

    2017-09-01

    Full Text Available The power plant location in the first hydroelectrial dams was a relevant issue at the end of XIX century and early XX. Different solutions were tried, some of them with very interesting aesthetics results and hydraulic and structural implications. Such is the case of La Jándula dam, inaugurated in 1930, that includes the power station inside the dam. This article examines the possible national and international inspirations of this singular solution, corroborating the hypothesis of its unprecedented nature. The collaboration of the architect Casto Fernández-Shaw in the design and integration of the engine room was decisive, because it achieved a result of an aesthetic quality and formal expressiveness unprecedented in a work of hydraulic engineering, as well as the birth of a style Shaw himself defined as architectural engineering.

  11. Studies on phytoremediation of copper using Pteridium aquilinum (bracken fern) in the presence of biostimulants and bioassay using Clarias gariepinus juveniles.

    Science.gov (United States)

    Olaifa, Flora Eyibio; Omekam, Anamese Jennifer

    2014-01-01

    A study was carried out to evaluate the uptake of copper from water containing 10 mg/L copper by Pteridium aquilinum (bracken fern) and Clarias gariepinus in the presence of five plant growth stimulants: Nitrogen: phosphorus: potassium (15-15-15: an inorganic fertilizer), pig, cattle, poultry, and a mixture of pig/cattle manures. A plant growth stimulant differentiated each treatment. A 96-hour bioassay using C. gariepinus was carried out at the end of the experiment to test the efficacy of the clean up by P. aquilinum. The control experiment contained no copper or plant growth stimulant. Fish survival, uptake of copper by P. aquilinum, C. gariepinus, concentration of copper in water, hematology and histopathology of the fish were assessed. Higher concentrations of copper were reported in P. aquilinum than in water or C. gariepinus. Low fish mortality was reported with the highest being 20% in the cattle manure-containing treatment.

  12. Marcos Fernández: «Chapter and explanation of the term hidalgo or hidalga», in Olla podrida a la española… (1655

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    Daniel M. Sáez Rivera

    2008-12-01

    Full Text Available An introduction and partial edition of the Marcos Fernández’ work Olla podrida a la española (Amberes [Amsterdam]: Felipe Van Eyck, 1655, text whose literary value has been recently pointed at last, as well as its interesting influence from Cervantes. In order to be accurate, which is edited is the last chapter with a burlesque etimology of the word hidalgo and the cast of a relative to Sancho Panza, called Toncho Panza. The text is showcased as a menipean satire in which grammatical and political views of the time are criticized, for instance the work by César Oudin or by Saavedra Fajardo. The editing criteria look for a new intermediate path between graphic conservatism (necessary in a inductive treaty of orthography such as the Olla podrida and modernization, which soothes the reading and understanding of the text, with the needed supply of linguistic and historical-literary notes.

  13. Humanismo cristiano en Diálogo de la dignidad del hombre, de Fernán Pérez de Oliva

    OpenAIRE

    Rivas Hernández, Ascensión

    2011-01-01

    En el Diálogo de la dignidad del hombre, Fernán Pérez de Oliva utiliza un género de larguísima tradición, y un tema muy arraigado en el Renacimiento que se remonta a la Roma antigua: el valor del hombre y su papel en el mundo. La obra de Oliva tiene como antecedentes a Manetti, a Pico y a toda la tradición clásica, tardomedieval y primorrenacentista sobre el asunto de la dignitas hominis, pero también a los libros sapienciales de la Biblia, a fray Luis de León, a la Historia natural de Plinio...

  14. Absence of promoting potential of bracken fern (Pteridium aquilinum) in rat urinary bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)-nitrosamine and uracil.

    Science.gov (United States)

    de Oliveira, M L; Souza Rocha, N; Fukushima, S; de Camargo, J L

    1995-01-01

    Conventional studies on bracken fern (Pteridium aquilinum; PA) carcinogenicity have used high dietary concentrations (around 30%) and long-term exposure (up to 52-70 weeks) without consideration of the multistep character of the chemical carcinogenesis process. The present study evaluated specifically the promoting potential of 3-5% dietary crude PA in the rat urinary bladder mucosa in a 32-week-long initiation-promotion assay for chemical carcinogenesis. Initiation of urothelial carcinogenesis was accomplished with N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN). Uracil (U) was provided through the diet in order to expand the population of initiated cells. Seven groups (G) of male Wistar rats were submitted to the following treatments: G1 = BBN (n = 8); G2 = U (n = 10); G3 = BBN-U (n = 9); G4 = BBN-PA-U-PA (n = 16); G5 = PA (n = 8); G6 = BBN-PA (n = 10); G7 = PA-U-PA (n = 12). At the end of the experiment rats presenting epithelial papillary or nodular hyperplasia (PNH), papillomas (PAP), or simultaneous PNH plus PAP numbered, respectively G1: 2-0-1; G2: 0-0-0; G3: 3-0-2; G4: 4-3-2; G5: 1-0-1; G6: 8-0-0; and G7: 0-0-0, with no significant differences in the incidence of lesions among the groups. More frequent and more severe lesions occurred in BBN-initiated animals, predominantly in those also exposed to uracil (G3 and G4). Low-dose crude bracken fern in the diet does not promote rat urinary bladder carcinogenesis after a 32-week period of exposure, even when the initiated urothelial cell population has been expanded through a mechanical stimulus.

  15. A plastid phylogeny and character evolution of the Old World fern genus Pyrrosia (Polypodiaceae) with the description of a new genus: Hovenkampia (Polypodiaceae).

    Science.gov (United States)

    Zhou, Xin-Mao; Zhang, Liang; Chen, Cheng-Wei; Li, Chun-Xiang; Huang, Yao-Moan; Chen, De-Kui; Lu, Ngan Thi; Cicuzza, Daniele; Knapp, Ralf; Luong, Thien Tam; Nitta, Joel H; Gao, Xin-Fen; Zhang, Li-Bing

    2017-09-01

    The Old World fern genus Pyrrosia (Polypodiaceae) offers a rare system in ferns to study morphological evolution because almost all species of this genus are well studied for their morphology, anatomy, and spore features, and various hypotheses have been proposed in terms of the phylogeny and evolution in this genus. However, the molecular phylogeny of the genus lags behind. The monophyly of the genus has been uncertain and a modern phylogenetic study of the genus based on molecular data has been lacking. In the present study, DNA sequences of five plastid markers of 220 accessions of Polypodiaceae representing two species of Drymoglossum, 14 species of Platycerium, 50 species of Pyrrosia, and the only species of Saxiglossum (subfamily Platycerioideae), and 12 species of other Polypodiaceae representing the remaining four subfamilies are used to infer a phylogeny of the genus. Major results and conclusions of this study include: (1) Pyrrosia as currently circumscribed is paraphyletic in relation to Platycerium and can be divided into two genera: Pyrrosia s.s. and Hovenkampia (gen. nov.), with Hovenkampia and Platycerium forming a strongly supported clade sister to Pyrrosia s.s.; (2) Subfamily Platycerioideae should contain three genera only, Hovenkampia, Platycerium, and Pyrrosia s.s.; (3) Based on the molecular phylogeny, macromorphology, anatomical features, and spore morphology, four major clades in the genus are identified and three of the four are further resolved into four, four, and six subclades, respectively; (4) Three species, P. angustissima, P. foveolata, and P. mannii, not assigned to any groups by Hovenkamp (1986) because of their unusual morphology, each form monospecific clades; (5) Drymoglossum is not monophyletic and those species previously assigned to this genus are resolved in two different subclades; (6) Saxiglossum is resolved as the first lineage in the Niphopsis clade; and (7) The evolution of ten major morphological characters in the

  16. Capacity of the aquatic fern (Salvinia minima Baker) to accumulate high concentrations of nickel in its tissues, and its effect on plant physiological processes

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, Ignacio I.; Espadas-Gil, Francisco; Talavera-May, Carlos; Fuentes, Gabriela; Santamaría, Jorge M., E-mail: jorgesm@cicy.mx

    2014-10-15

    Highlights: • We document the capacity of an aquatic fern to hyper-accumulate Ni. • Effects of high Ni concentrations uptake on plant performance is documented. • High concentration of Ni in tissues damage photosynthesis. • Damage is related to carboxylation mechanisms than to electron transfer efficiency. • S. minima is a good candidate for remediation of water bodies contaminated with Ni. - Abstract: An experiment was designed to assess the capacity of Salvinia minima Baker to uptake and accumulate nickel in its tissues and to evaluate whether or not this uptake can affect its physiology. Our results suggest that S. minima plants are able to take up high amounts of nickel in its tissues, particularly in roots. In fact, our results support the idea that S. minima might be considered a hyper-accumulator of nickel, as it is able to accumulate 16.3 mg g{sup −1} (whole plant DW basis). Our results also showed a two-steps uptake pattern of nickel, with a fast uptake of nickel at the first 6 to 12 h of being expose to the metal, followed by a slow take up phase until the end of the experiment at 144 h. S. minima thus, may be considered as a fern useful in the phytoremediation of residual water bodies contaminated with this metal. Also from our results, S. minima can tolerate fair concentrations of the metal; however, at concentrations higher than 80 μM Ni (1.5 mg g{sup −1} internal nickel concentration), its physiological performance can be affected. For instance, the integrity of cell membranes was affected as the metal concentration and exposure time increased. The accumulation of high concentrations of internal nickel did also affect photosynthesis, the efficiency of PSII, and the concentration of photosynthetic pigments, although at a lower extent.

  17. Growth dynamics of fine roots in a coniferous fern forest site close to Forsmark in the central part of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Hans; Stadenberg, Ingela (SLU, Dept. of Ecology and Environmental Research, Uppsala (Sweden))

    2007-12-15

    The seasonal growth dynamics of live and dead roots for trees and the field layer species (g/m2, varying diameter fractions) and live/dead ratios were analysed at a fresh/moist coniferous fern forest site close to the nuclear power plant at Forsmark in the central eastern parts of Sweden. The changes in depth distribution of fine roots were observed at depth intervals of the top humus horizon down to 40 cm in the mineral soil profile. The bulk of living fine roots of trees (< 1 mm in diameter) were found in the mineral soil horizon the total profile down to 40 cm of the mineral soil, where 89, 82, 83 and 89% of the total amount in the whole profile were found. The upper 2.5 cm part of the humus layer contained 83, 81, 100 and 100% of all roots of the humus layer on the four different sampling occasions. High amounts of living fine roots were found in the upper 10 cm of the mineral soil horizon viz. 84, 76, 91 and 69% of the total mineral soil layer. Consequently, both the top soil horizons of the humus and the mineral soil layers were heavily penetrated by living fine roots. The highest proportion of living fine roots was found in the top 2.5 cm of the humus layer. Accordingly, the live/dead ratio of fine roots (< 1 mm in diameter) decreased from the top of the humus layer to the lower part of mineral soil horizon from 8.0-0.3, 0.8-0.2, 4.4-0.4 and 3.3-0.7 (g g-1) for the four sampling occasions, respectively. We concluded that the decrease in the live/ dead ratio was related to decreased vitality with depth of the fine roots in the soil profile. The highest live/dead ratio was found in the upper 2.5 cm of the humus layer for both the tree and field-layer species. This distribution pattern was most evident for tree fine roots < 1 mm in diameter. The mean fine-root biomass (live tissue < 1 mm in diameter) of tree species for the total profile varied on the four sampling occasions between 317, 113, 139 and 248 g m-2. The related fine root necromass (dead tissue

  18. Intoxicação experimental aguda por samambaia (Pteridium aquilinum em bovinos Experimental acute poisoning by bracken fern (Pteridium aquilinum in cattle

    Directory of Open Access Journals (Sweden)

    Bruno L. Anjos

    2009-09-01

    conflitantes, não permitindo concluir se a coagulação intravascular disseminada tem participação na patogênese das hemorragias nessa intoxicação. A citopatologia e histopatologia da medula óssea dos quatro bovinos intoxicados revelaram acentuada diminuição no número de células hematopoéticas das três linhagens medulares, caracterizando insuficiência medular por aplasia; conclui-se que apenas eventos da hemostasia primária devidos a trombocitopenia são responsáveis pelas hemorragias. Na hemocultura de três dos bovinos intoxicados houve crescimento de Klebsiella oxytoca, Staphylococcus hyicus e Staphylococcus aureus, indicando que a septicemia, facilitada pela neutropenia, pode ter participação na causa da morte de bovinos na intoxicação aguda pela ingestão de P. aquilinum. Aspectos adicionais de interesse na reprodução da intoxicação aguda por samambaia em bovinos deste relato incluem o desenvolvimento de hematúria na doença aguda e a apresentação da chamada forma laríngea da doença.This experiment was design to address the following points in relation to the acute poisoning by bracken fern (Pteridium aquilinum in cattle: 1 the severity of the thrombocytopenia in different stages of the intoxication and its relationship to possible deficits in the secondary hemostasis, 2 the relationship between neutropenia and the morphological signs of septicemia occasionally found at necropsy, and 3 the mechanism of anemia and its relationship with blood loss, medium life of erythrocytes and the progress of the disease. The fresh green upper parts of P. aquilinum were fed to four mixed breed calves with average age of 18 months and weights ranging from 190 to 215 kg. A calf of similar age and weight was kept together with the other four under the same conditions, except for the ingestion of P. aquilinum. The four fern-fed calves died with typical features of acute bracken fern poisoning after being fed with the plant for 53-58 days daily doses of 8.0, 8

  19. Fernán Caballero, pionera en la recolección del romancero de tradición oral moderna (Fernan Caballero, a Pioneer in the Collection of Ballads of Modern oral Tradition

    Directory of Open Access Journals (Sweden)

    Carmen de la Vega de la Muela

    2012-12-01

    Full Text Available Resumen: Cecilia Böhl de Faber, “Fernán Caballero”, es pionera en la recolección de romances tradicionales por tierras andaluzas en las primeras décadas del siglo XIX. A través de sus escritos costumbristas, la novelista presenta todo un repertorio de romances y canciones populares que serán de gran trascendencia para los posteriores estudios del folclore andaluz.Abstract: Cecilia Böhl Faber, "Fernán Caballero", is a pioneer in the collection of traditional ballads through Andalusia in the early decades of the nineteenth century. Through his writings customs, the novelist presents a repertoire of ballads and folk songs that will be of great importance for the further study of Andalusian folklore.

  20. Serie de productos educomunicativos en audio sobre prevención de problemas comunes en adolescentes, para el Departamento de Tutoría y Bienestar Estudiantil del Liceo Municipal Fernández Madrid de Quito

    OpenAIRE

    Narváez Coronel, Alba Bibiana

    2012-01-01

    El presente trabajo consiste en desarrollar una propuesta educomunicativa presentada al Liceo “Fernández Madrid”, Institución educativa donde el Departamento de Tutoría y Bienestar Estudiantil, DTBE, realiza programas referentes a prevención de problemas comunes en adolescentes. La propuesta plantea la elaboración un producto comunicacional, destinado a ser utilizado como herramienta pedagógica, desarrollada para responder a las necesidades del DTBE, en los programas de prev...

  1. Un escritor ante las instituciones: el caso de Nicolás Fernández de Moratín (1737-1780

    Directory of Open Access Journals (Sweden)

    Philip DEACON

    2009-11-01

    Full Text Available RESUMEN: En la España dieciochesca, cuando el mercado editorial no se había desarrollado lo suficiente para que un hombre de letras viviera sólo de su pluma, el escritor tenía que aprender a navegar por el complejo mundo institucional. El peso de entidades como la monarquía, la nobleza y la Iglesia seguía siendo grande, pero el espíritu renovador de la época dio lugar a nuevos organismos como las academias, sociedades económicas, e incluso instituciones menos definidas como la prensa y la tertulia cultural. Este artículo traza la carrera de Nicolás Fernández de Moratín, describiendo cómo se enfrentó con esas entidades y precisando cómo influyeron en sus escritos. Algunas instituciones como las educativas, profesionales o eclesiásticas conformaron las actividades del escritor tanto en el terreno ideológico como en el estilístico; otras, como en el caso de Moratín la Sociedad Económica Matritense, abren nuevas perspectivas para dar resultados literarios singulares al producirse una confluencia entre formas tradicionales y temas nuevos.ABSTRACT: In eighteenth-century Spain, where the literary world was insufficiently developed to allow authors to live by the pen, writers had to learn to negotiate the complex ways of established institutions. The prevailing influence of the monarchy, nobility and Church was great, but the spirit of renewal evident during the period gave rise to new organizations such as the royal academies, economic societies and less clearly identifiable institutions such as the press or the cultural club. The present article outlines the career of Nicolás Fernández de Moratín, demonstrating how the author negotiated these organizations and how they influenced his writings. Some institutions, like those belonging to the educational, professional and ecclesiastical worlds, influenced the writer both in an ideological and stylistic sense; others, as in Moratín’s case the Madrid Economic Society, provided an

  2. Land plants drive photorespiration as higher electron-sink: comparative study of post-illumination transient O2 -uptake rates from liverworts to angiosperms through ferns and gymnosperms.

    Science.gov (United States)

    Hanawa, Hitomi; Ishizaki, Kimitsune; Nohira, Kana; Takagi, Daisuke; Shimakawa, Ginga; Sejima, Takehiro; Shaku, Keiichiro; Makino, Amane; Miyake, Chikahiro

    2017-09-01

    In higher plants, the electron-sink capacity of photorespiration contributes to alleviation of photoinhibition by dissipating excess energy under conditions when photosynthesis is limited. We addressed the question at which point in the evolution of photosynthetic organisms photorespiration began to function as electron sink and replaced the flavodiiron proteins which catalyze the reduction of O 2 at photosystem I in cyanobacteria. Algae do not have a higher activity of photorespiration when CO 2 assimilation is limited, and it can therefore not act as an electron sink. Using land plants (liverworts, ferns, gymnosperms, and angiosperms) we compared photorespiration activity and estimated the electron flux driven by photorespiration to evaluate its electron-sink capacity at CO 2 -compensation point. In vivo photorespiration activity was estimated by the simultaneous measurement of O 2 -exchange rate and chlorophyll fluorescence yield. All C3-plants leaves showed transient O 2 -uptake after actinic light illumination (post-illumination transient O 2 -uptake), which reflects photorespiration activity. Post-illumination transient O 2 -uptake rates increased in the order from liverworts to angiosperms through ferns and gymnosperms. Furthermore, photorespiration-dependent electron flux in photosynthetic linear electron flow was estimated from post-illumination transient O 2 -uptake rate and compared with the electron flux in photosynthetic linear electron flow in order to evaluate the electron-sink capacity of photorespiration. The electron-sink capacity at the CO 2 -compensation point also increased in the above order. In gymnosperms photorespiration was determined to be the main electron-sink. C3-C4 intermediate species of Flaveria plants showed photorespiration activity, which intermediate between that of C3- and C4-flaveria species. These results indicate that in the first land plants, liverworts, photorespiration started to function as electron sink. According to

  3. Formas da gramática renascentista: percepção e abordagem da diversidade linguística em Fernão de Oliveira Grammar forms in the renaissance period: perception and a linguistic diversity approach in Fernão de Oliveira

    Directory of Open Access Journals (Sweden)

    Ronaldo de Oliveira Batista

    2010-01-01

    Full Text Available Partindo de diretrizes teórico-metodológicas da Historiografia Linguística (como a relação entre clima de opinião e produção linguística, o artigo reconstrói e interpreta abordagens da variação linguística, percebida e comentada por Fernão de Oliveira, na primeira gramática da língua portuguesa (1536. Em busca da construção de uma identidade linguística, o pioneiro gramático procurou nas particularidades do idioma bases para afirmação e elevação do caráter nacional do povo português. Procura-se, a partir desse estudo de caso, situar o trabalho de Oliveira numa tradição gramatical renascentista típica do século XVI.Taking as a parameter linguistic historiography methodologies (as the relationship between 'climate of opinion' and language production, the article reconstructs and interprets approaches to linguistic variation, perceived and discussed by Fernão de Oliveira, in the first grammar of Portuguese (1536. In search of building a linguistic identity, the pioneer grammarian sought, in the peculiar characteristics of the language, basis for the affirmation and elevation of the national character of the Portuguese people. With these in mind, this case study aims to locate Oliveira's study in a grammatical tradition typical of the sixteenth century Renaissance period.

  4. Contrasting P-T paths of shield and rejuvenated volcanism at Robinson Crusoe Island, Juan Fernández Ridge, SE Pacific

    Science.gov (United States)

    Reyes, Javier; Lara, Luis E.; Morata, Diego

    2017-07-01

    A remarkable expression of intraplate volcanism is the occurrence of evolutionary stages with important variations of magmatic processes and products. Plumbing systems and storage conditions seem to be different for shield and rejuvenated volcanism, two classical stages notably preserved in Robinson Crusoe Island, Juan Fernández Ridge in the SE Pacific Ocean. We here present first order geochemical features for rocks from both shield and rejuvenated stages and through geothermobarometry and textural analysis we unravel their contrasting ascent and storage history. The shield stage ( 3.8 Ma) is represented by a 900 m thick sequence of basalt, picrobasalt and picrite lava flows forming subsets according their chemistry and mineralogy: 'differentiated', 'near-primitive' and 'olivine-rich' lavas. Pressure estimates for in equilibrium assemblages are Robinson Crusoe Island, which also controlled volcanic processes on surface and finally shaped the island. We propose the existence of shallow magmatic reservoirs in the shield stage, where the ascending magmas would have been stored and differentiated. On the other hand, rejuvenated magmas experimented rapid ascent with polybaric crystallization and sometimes short-time storage in low-volume reservoirs. Similar conditions have been proposed in other oceanic islands suggesting that shallow reservoirs in the shield stage and deeper crystallization of more alkaline magmas in the rejuvenated stage seems to describe a global pattern.

  5. Genetic variation (AFLPs and nuclear microsatellites) in two anagenetically derived endemic species of Myrceugenia (Myrtaceae) on the Juan Fernández Islands, Chile.

    Science.gov (United States)

    López-Sepúlveda, Patricio; Takayama, Koji; Greimler, Josef; Peñailillo, Patricio; Crawford, Daniel J; Baeza, Marcelo; Ruiz, Eduardo; Kohl, Gudrun; Tremetsberger, Karin; Gatica, Alejandro; Letelier, Luis; Novoa, Patricio; Novak, Johannes; Stuessy, Tod F

    2013-04-01

    Anagenesis (or phyletic evolution) is one mode of speciation that occurs in the evolution of plants on oceanic islands. Of two endemic species on the Juan Fernández Islands (Chile), Myrceugenia fernandeziana and M. schulzei (Myrtaceae), believed to have originated anagenetically from different continental progenitors, the first is endemic to Robinson Crusoe Island and has no clear tie to continental relatives; the last is endemic to the younger island, Alejandro Selkirk Island, and has close affinity to M. colchaguensis in mainland Chile. Using AFLPs and six nuclear microsatellites from 381 individuals representing 33 populations, we determined patterns of genetic variation within and among populations on both islands and between those of the islands and mainland. Considerable genetic variation was found within populations on both islands. The level of gene diversity within M. schulzei was equivalent to that of its close continental relative M. colchaguensis. Genetic diversity was not partitioned geographically in M. fernandeziana and was weakly so and nonsignificantly in M. schulzei. The high genetic variation in both taxa is most likely due to anagenetic speciation. Subsidence of the older island Robinson Crusoe, landscape erosion, and restructuring of communities have severely reduced the overall island population to a single panmictic system. On the younger and less modified Alejandro Selkirk Island, slightly stronger patterns of genetic divergence are seen in M. schulzei. Because both species are genetically diverse and number in the thousands of individuals, neither is presently endangered in the archipelago.

  6. RICHNESS AND FLORISTIC COMPOSITION OF THE FERN COMMUNITY IN RIPARIAN FOREST OF THE RIVER ‘CADEIA’, IN RIO GRANDE DO SUL STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Ivanete Teresinha Mallmann

    2014-03-01

    Full Text Available http://dx.doi.org/10.5902/1980509813327The present study analyzed richness and specific composition of the fern community in fragments fromthe riparian forest of river ‘Cadeia’, under different levels of human impact, in Santa Maria do Herval, RioGrande do Sul state, Brazil. An amount of 120 sample units were delimited, equitably distributed in threefragments (FI, II and III in which all species were surveyed and the richness was recorded. The floristiccomposition among fragments was compared using Jaccard’s index and spatial distribution of units wasevaluated through multidimensional scaling. Richness data were presented in the form of rarefaction curvesbased on samples and non-parametric diversity estimators. A total of 40 species were found, belonging to13 families. The greater floristic similarity was between FI and FII. Sample units from FI formed the mostdefined grouping and they had more exclusive species than the others. The rarefaction curve for the totalsampling almost reached the asymptote and estimators indicated a maximum of 45 species, which meansthat the majority of species was surveyed at the study site. A decreasing gradient of mean richness per unitwas observed as the urbanization increased in the matrix habitat of the fragments. These results form a database to be used in management, conservation and reforestation measures in degraded riparian forests. Theycan be directly compared to results from other studies that used rarefaction and richness estimators, whichis not possible to do with many of the surveys accomplished in Brazil so far.

  7. Heterogeneous photo-Fenton treatment for the reduction of pharmaceutical contamination in Madrid rivers and ecotoxicological evaluation by a miniaturized fern spores bioassay.

    Science.gov (United States)

    Rodríguez-Gil, José L; Catalá, Myriam; Alonso, Silvia González; Maroto, Raúl Romo; Valcárcel, Yolanda; Segura, Yolanda; Molina, Raúl; Melero, Juan A; Martínez, Fernando

    2010-06-01

    Fifty-six pharmaceuticals of various chemical groups, such as anti-inflammatory, antibacterial and cardiovascular drugs, were detected in four selected river waters receiving sewage effluents in the Community of Madrid (Spain). A promising approach for the degradation of those residues is the application of a photo-Fenton treatment. Several new bioassays using fern spores were employed for the evaluation of acute and chronic toxicity based on mitochondrial activity, DNA and chlorophyll quantifications of as-received river water and photo-Fenton-treated samples. photo-Fenton treatment provided a high degree of total organic carbon mineralization with up to 70% reduction for river water samples. In addition, the elimination of most of the studied pharmaceutical compounds was confirmed. A few compounds, however (salicylic acid, ofloxacin, caffeine, cotinine and nicotine), seemed more resistant, with after-treatment concentrations between 4 and 44ngL(-1). Nicotine showed the most refractory behaviour with concentrations ranging from 29 to 224ngL(-1) for treated samples. Photo-Fenton treatment yielded a significant decrease in acute and chronic toxicity, even though some residual toxicity remained after treatment. This fact seemed to be related to the presence of toxicants in the water matrix, probably of inorganic nature, rather than the toxic effect of the studied pharmaceutical compounds, as revealed by the effective removal of these compounds and high TOC mineralization of photo-Fenton treatments.

  8. Study on transportation and accumulation mechanism of cadmium in metal-hyperaccumulating fern, Athyrium yokoscense, by synchrotron radiation x-ray fluorescence analysis

    International Nuclear Information System (INIS)

    Taoka, Hiroki; Nakai, Izumi; Hokura, Akiko; Goto, Fumiyuki; Yoshihara, Toshihiro; Abe, Tomoko; Terada, Yasuko

    2012-01-01

    High energy synchrotron radiation micro X-ray fluorescence (HE-SR-μ-XRF) analysis and X-ray absorption fine structure (XAFS) analysis were applied to reveal accumulation mechanism of Cd in a generated callus of Cd hyperaccumulator fern Athyrium yokoscense. The effects of plant age on the distributions and the chemical forms of Cd were examined using the plant grown in the 1/2 M Murashige and Skoog (MS) medium containing 200 μM Cd. The callus grew vigorously with periodical medium change. The μ-XRF imaging of the mature and young root showed that Cd was located around the cell wall of the epidermis, cortex, endodermis and vascular bundles. It is estimated that Cd absorbed from the root was transported to the shoots via the apoplast. On the other hand, Cd was accumulated in the cell wall of the epidermis, cortex and vascular bundles in the stem. Furthermore, the concentration of Cd in the vascular bundles of the mature stem was higher than that of the young stem. On the other hand, Cd located in whole area in the leaf. The Cd K-edge XAFS analysis revealed that the majority of Cd in the roots of both mature and immature stages of A. yokoscense is bounded to the oxygen ligands. In contrast, it is found that Cd was bound to sulfur ligands as well as to oxygen ligands in the shoots. (author)

  9. “The Journey” as an Expression of Mysticism in Sergio Fernández’s Segundo Sueño

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    Claudia Ramos Aguilar

    2015-02-01

    Full Text Available In this article the relationship which can be established between the dreamsof Anabasis in sor Juana Inés de la Cruz’s poem, Primero sueño and the novelby Sergio Fernández, Segundo sueño, is analized in a concordance where the soul during its journey through the supra lunar spheres, or in the transmutation of natural elements —rain, snow and mud—, experiences the mystery of itsencounter with the divine as a process of initiation.In the poem, the pursuit of higher knowledge is a trap; in the novel, the crossroads is found in the transgressive eroticism. These two trips of anabasis,the first and the second dream, translate the wink announcing the succession ina fall. In both cases, the excess of the soul, a tragic hero mask, melts the wingsof Icarus and conduces to the death of Phaeton, the death of the inexperienced charioteer of the divine chariot.

  10. A new species of Ergasilus Nordmann, 1832 (Copepoda: Cyclopoida: Ergasilidae) from Bryconops giacopinii Fernández-Yépez (Characidae) in the Vichada River Basin, Colombia.

    Science.gov (United States)

    Muriel-Hoyos, Felipe; Santana-Piñeros, Ana María; Cruz-Quintana, Yanis; Suárez-Morales, Eduardo

    2015-11-01

    A new copepod species, Ergasilus curticrus n. sp. is described based on 14 female specimens collected from the gills of the characid teleost Bryconops giacopinii Fernández-Yépez, captured in the Vichada River Basin in Colombia. The new species has a unique combination of characters including: (i) 2-segmented endopods in legs 1 and 4; (ii) a semi-pinnate, falciform seta on the terminal segment of the first leg exopod; (iii) a 1-segmented fourth leg exopod; (iv) a reduced fifth leg with a single seta; and (v) a circular structure fused to a groove near the lateral margins of the second pedigerous tergite. Only two other known congeners have a 1-segmented leg 4 exopod, E. coatiarus Araujo & Varella, 1998 and E. iheringi Tidd, 1942. Among other characters, they differ from the new species by the lack of a semi-pinnate, falciform seta on the terminal exopodal segment of leg 1 and in the structure and armature of the fifth leg. The prevalence of E. curticrus n. sp. was 13.6% and its mean abundance was 0.4 specimens per host. This is the first new species of Ergasilus Nordmann, 1832 described from the Orinoco River Basin.

  11. Co-occurrence patterns of common and rare leaf-litter frogs, epiphytic ferns and dung beetles across a gradient of human disturbance.

    Directory of Open Access Journals (Sweden)

    Johan A Oldekop

    Full Text Available Indicator taxa are commonly used to identify priority areas for conservation or to measure biological responses to environmental change. Despite their widespread use, there is no general consensus about the ability of indicator taxa to predict wider trends in biodiversity. Many studies have focused on large-scale patterns of species co-occurrence to identify areas of high biodiversity, threat or endemism, but there is much less information about patterns of species co-occurrence at local scales. In this study, we assess fine-scale co-occurrence patterns of three indicator taxa (epiphytic ferns, leaf litter frogs and dung beetles across a remotely sensed gradient of human disturbance in the Ecuadorian Amazon. We measure the relative contribution of rare and common species to patterns of total richness in each taxon and determine the ability of common and rare species to act as surrogate measures of human disturbance and each other. We find that the species richness of indicator taxa changed across the human disturbance gradient but that the response differed among taxa, and between rare and common species. Although we find several patterns of co-occurrence, these patterns differed between common and rare species. Despite showing complex patterns of species co-occurrence, our results suggest that species or taxa can act as reliable indicators of each other but that this relationship must be established and not assumed.

  12. Study on accumulation mechanism of lead and copper in metal-hypertolerant fern, Athyrium yokoscense, by micro-XRF analysis utilizing synchrotron radiation

    International Nuclear Information System (INIS)

    Mitsuo, Sakiko; Kashiwabara, Teruhiko; Hokura, Akiko; Nakai, Izumi; Kitajima, Nobuyuki; Goto, Fumiyuki; Yoshihara, Toshihiro; Abe, Tomoko

    2009-01-01

    Athyrium yokoscense is a plant which accumulates high level of heavy metals such as Cu, Zn, Pb and Cd, and is expected to be used for phytoremediation. This paper reports the distribution and the chemical forms of Pb and Cu in underground parts (root and old leaf stalks) of the metal-hypertolerant fern, A. yokoscense, by synchrotron radiation micro-XRF imaging and micro-XANES analyses. The old and new tissues of root and leaf stalks were prepared for micro-XRF analysis. The XRF imaging of the young root revealed that K, Cu and Zn were distributed in whole area of cross-section, whereas Pb was found in a certain part of the epidermal tissue. For the old root, Pb and Cu were mainly distributed in the cell wall of the whole tissue. The distribution of heavy metal in old tissue is different from those of new tissue, and consequently it was assumed that the root at different age have different heavy metal accumulation mechanism. Alternatively, for the old leaf stalks, Cu and Pb were highly accumulated in a specific part located around the vascular tissue. Cu K-edge micro-XANES analysis indicated that the chemical form of Cu at the Cu accumulating point was Cu (II). (author)

  13. Modelación de la conectividad de las subpoblaciones de la langosta de Juan Fernández (Jasus frontalis, a través de un modelo biofísico Modeling the connectivity of Juan Fernández rock lobster (Jasus frontalis, subpopulations through a biophysical model

    Directory of Open Access Journals (Sweden)

    Javier Porobic

    2012-09-01

    Full Text Available El archipiélago de Juan Fernández y el de las islas Desventuradas, corresponden a dos pequenos grupos de islas oceánicas, separadas entre sí 460 mn y ubicadas aproximadamente a 360 mn frente a la costa chilena. La economía local de estas islas se basa casi exclusivamente en la extracción y comercialización de recursos marinos, focalizados principalmente en la explotación de la langosta (Jasusfrontalis. Esta especie endémica se encuentra distribuída en ambos archipiélagos conformando una metapoblación, donde su dinámica y estructura poblacional sería modulada por forzantes oceanográficos, especialmente durante su prolongada fase larval planctónica. Se evaluó la estructura poblacional y el grado de conectividad-retención dentro y entre las diferentes islas mediante el uso de modelos biofísicos acoplados (modelos hidrodinámicos provenientes del modelo OFES y un modelo individuo basado de J. frontalis. El análisis de los resultados del modelo hidrodinámico indica la presencia de estructuras de mesoescala asociadas al sistema de islas. Índices provenientes del modelo biofísico muestran niveles importantes de conectividad-retención dentro y entre los sistemas de islas y una fuerte variación interanual de estos. Los resultados de la modelación biofísica indican que la varibilidad en el reclutamiento asociado al archipiélago de Juan Fernández depende mayoritariamente de larvas originadas en este mismo sistema, con un aporte importante de reclutas hacia el archipiélago de las Desventuradas. Se realizaron estudios de sensibilidad del modelo biofísico para identificar forzantes potenciales de las variables dependientes del modelo (e.g. índices de conectividad-retención, resultando en que los patrones temporales y espaciales reproductivos, la duración del estadio larval y la temporada (ano son altamente significativos. Finalmente, se propone que J. frontalis presenta una estructura metapoblacional con un alto nivel de

  14. Using native epiphytic ferns to estimate the atmospheric mercury levels in a small-scale gold mining area of West Java, Indonesia.

    Science.gov (United States)

    Kono, Yuriko; Rahajoe, Joeni S; Hidayati, Nuril; Kodamatani, Hitoshi; Tomiyasu, Takashi

    2012-09-01

    Mercury pollution is caused by artisanal and small-scale gold mining (ASGM) operations along the Cikaniki River (West Java, Indonesia). The atmosphere is one of the primary media through which mercury can disperse. In this study, atmospheric mercury levels are estimated using the native epiphytic fern Asplenium nidus complex (A. nidus) as a biomonitor; these estimates shed light on the atmospheric dispersion of mercury released during mining. Samples were collected from 8 sites along the Cikaniki Basin during September-November, 2008 and September-November, 2009. The A. nidus fronds that were attached to tree trunks 1-3m above the ground were collected and measured for total mercury concentration using cold vapor atomic absorption spectrometry (CVAAS) after acid-digestion. The atmospheric mercury was collected using porous gold collectors, and the concentrations were determined using double-amalgam CVAAS. The highest atmospheric mercury concentration, 1.8 × 10(3) ± 1.6 × 10(3) ngm(-3), was observed at the mining hot spot, and the lowest concentration of mercury, 5.6 ± 2.0 ngm(-3), was observed at the remote site from the Cikaniki River in 2009. The mercury concentrations in A. nidus were higher at the mining village (5.4 × 10(3) ± 1.6 × 10(3) ngg(-1)) than at the remote site (70 ± 30 ngg(-1)). The distribution of mercury in A. nidus was similar to that in the atmosphere; a significant correlation was observed between the mercury concentrations in the air and in A. nidus (r=0.895, P<0.001, n=14). The mercury levels in the atmosphere can be estimated from the mercury concentration in A. nidus using a regression equation: log (Hg(A.nidu)/ngg(-1))=0.740 log (Hg(Air)/ngm (-3)) - 1.324. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Mitochondrial activity in fern spores of Cyathea costaricensis as an indicator of the impact of land use and water quality in rivers running through cloud forests.

    Science.gov (United States)

    Rodríguez-Romero, Alexis Joseph; Rico-Sánchez, Axel Eduardo; Catalá, Myriam; Sedeño-Díaz, Jacinto Elías; López-López, Eugenia

    2017-12-01

    Early-warning biomarkers, such as mitochondrial activity, have become a key tool in ecosystem assessment. This study aims to evaluate the response of mitochondrial activity in spores of the autochthonous fern Cyathea costaricensis as a bioassessment tool concurrently with land use and physicochemical evaluation in 11 sites along Bobos River, Veracruz, Mexico, to assess river water quality. Bobos River is located in the Nautla basin, northeastern Veracruz (Mexico); the upper river runs through a protected natural area (Filobobos River and adjacent areas). The study involved three monitoring periods: February, June and September 2014. In each study site, physicochemical water quality parameters were recorded to calculate the Water Quality Index (WQI); also, study sites were characterized in terms of land use. Water samples were collected to perform bioassays where spores of C. costaricensis were exposed to samples to assess mitochondrial activity; a positive control exposure test was run under controlled conditions to maximize mitochondrial activity. A Principal Component Analysis was performed to correlate land-use attributes with environmental variables and mitochondrial activity. Three river sections were identified: the upper portion was characterized by the dominance of native vegetation, the highest WQI (in September), and the lowest mitochondrial activity (63.87%-77.47%), related to the geological nature of the basin and high hardness levels. Mitochondrial activity peaked in September (98.32% ± 9.01), likely resulting from nutrient enrichment in the rainy season, and was lowest in February (74.54% ± 1.60) (p human impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia (Canada); D' Angelo, Jose A. [Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Area de Quimica, Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Centro Universitario - M5502JMA - Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, Bloomington, IN 47405-2208 (United States); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

    2009-08-01

    Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the ''coalified layer'' with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: ''vitrinite (mesophyll) + cuticle (biomacropolymer) = compression''. Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. (author)

  17. Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

    Science.gov (United States)

    Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Keefe, D.

    2009-01-01

    Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the "coalified layer" with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: "vitrinite (mesophyll) + cuticle (biomacropolymer) = compression". Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. ?? 2009 Elsevier B.V. All rights reserved.

  18. Ciclo anual de la clorofila-α satelital en el archipiélago de Juan Fernández (33°S, Chile

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2012-09-01

    Full Text Available La variabilidad espacial y temporal del ciclo anual de la clorofila-α en el archipiélago de Juan Fernández se analiza usando ocho anos de datos satelitales de clorofila-α, viento, corrientes y nivel del mar. Este archipiélago está conformado por tres islas: Robinson Crusoe-Santa Clara (RC-SC y Alejandro Selkirk (AS. Las islas RC-SC se encuentran en una región de alta energía cinética y mayores concentraciones de clorofila-α definida como Zona de Transición Costera, en cambio la isla AS se encuentra en una región de baja energía cinética y menores concentraciones de clorofila-α denominada Zona Oceánica. RC-SC posee un incremento de las concentraciones de clorofila-a en el lado suroeste, mientras que AS posee sus mayores concentraciones en el lado oeste, indicando la presencia de procesos forzantes diferentes. En ambas islas el ciclo anual de la clorofila es significativo y comienza a incrementar en abril, alcanzando valores relativamente altos entre junio y noviembre, disminuyendo hacia diciembre, hasta alcanzar un mínimo hacia fines de marzo. Este ciclo anual aparece desacoplado con el viento y acoplado con la energía cinética. Incrementos invernales de clorofila-a aparecen vinculados con remolinos de mesoescala provenientes de la zona continental, mientras que incrementos primaverales se podrían asociar a procesos locales vinculados al "efecto masa de isla". En ambas islas existen incrementos significativos de la clorofila-a en la banda anual y cuasi-bianual, pero sólo en AS se encontró una fluctuación significativa en la banda interanual vinculada con el Nino y la Oscilación del Sur.

  19. La recepción de la teoría cromosómica-mendeliana en España. La contribución de José Fernández Nonídez

    OpenAIRE

    Pinar, Susana

    1999-01-01

    On this paper I would like to make known the work of José Fernández Nonídez as introductor in Spain of the Mendelian-Chromosome theory developed in Morgan's school. Likewise, I make a especial mention of the training stage of Nonídez in América, I analyce his books Herencia Mendeliana and Variación y herencia, and I give especial mention of his later task as histologist since his return to the United States and until his death.

    Con este...

  20. Carlos Fernández Casado y José Acuña: los primeros puentes de altura estricta. Jaén, 1933-1935

    Directory of Open Access Journals (Sweden)

    Burgos, A.

    2012-12-01

    Full Text Available The bridge design catalogue “Puentes de altura Estricta” (Strict Height Bridges was one of the greatest creations of the brilliant spanish civil engineer Carlos Fernandez Casado. It was designed at the early 1930’s. It had a great relevance in the Spanish Civil Engineering of the 20th century. Nevertheless, its origins are little known. The first materializations of the “Collection” were six bridges that were constructed in the Jaén province, between 1933 and 1935. They were possible thanks to the determined support of other civil engineer, Jose Acuña y Gómez de la Torre. Later also he carried out the work himself. With this research its process of design and construction is reconstructed. Also bridges are described as they have come to the present day. With all this it is expected its great value as heritage elements be recognized.

    La “Colección de Puentes de Altura Estricta” fue una de las mayores creaciones del genial ingeniero de caminos español Carlos Fernández Casado. Fue diseñada a principios de los años 1930 y tuvo una gran trascendencia en la Ingeniería civil española del siglo XX. No obstante, sus orígenes son poco conocidos. Las primeras materializaciones de la “Colección” fueron seis puentes que se construyeron en la provincia de Jaén, entre 1933 y 1935. Fueron posibles gracias al decidido apoyo que prestó otro ingeniero de caminos, José Acuña y Gómez de la Torre. Posteriormente también se hizo cargo de su ejecución material. Con esta investigación se pretende reconstruir su proceso de diseño y construcción. También se describen los puentes tal como han llegado hasta nuestros días. Con todo ello se espera contribuir a que sea reconocido su gran valor como elementos patrimoniales.

  1. Madagascar sheds new light on the molecular systematics and biogeography of grammitid ferns: New unexpected lineages and numerous long-distance dispersal events.

    Science.gov (United States)

    Bauret, Lucie; Gaudeul, Myriam; Sundue, Michael A; Parris, Barbara S; Ranker, Tom A; Rakotondrainibe, France; Hennequin, Sabine; Ranaivo, Jaona; Selosse, Marc-André; Rouhan, Germinal

    2017-06-01

    Based on a worldwide phylogenetic framework filling the taxonomic gap of Madagascar and surrounding islands of the Western Indian Ocean (WIO), we revisited the systematics of grammitid fern species (Polypodiaceae). We also investigated the biogeographic origin of the extant diversity in Madagascar and estimated the relative influence of vicariance, long-distance dispersals (LDD) and in situ diversification. Phylogenetic inferences were based on five plastid DNA regions (atpB, rbcL, rps4-trnS, trnG-trnR, trnL-trnF) and the most comprehensive taxonomic sampling ever assembled (224 species belonging to 31 out of 33 recognized grammitids genera). 31 species from Madagascar were included representing 87% of the described diversity and 77% of the endemics. Our results confirmed a Paleotropical clade nested within an amphi-Atlantic grade. In addition, we identified three new major clades involving species currently belonging to Grammitis s.l., Ctenopterella and Enterosora. We resolved for the first time Grammitis s.s. as monophyletic, and Ctenopterella (newly tested here) and Enterosora as polyphyletic. The Neotropical genus Moranopteris was shown to also occur in Madagascar through a newly discovered species. Most importantly, we suggest a >30% inflation of the species number in the WIO due to the hidden diversity in >10 cryptic lineages, best explained by high morphological homoplasy. Molecular dating and ancestral areas reconstruction allowed identifying the Neotropics as the predominant source of LDD to the African-WIO region, with at least 12 colonization events within the last 20Ma. Repeated eastward migrations may be explained by transoceanic westerly winds transporting the dust-like spores. Tropical Asia s.l. would also have played a (minor) role through one dispersal event to Madagascar at the end of the Oligocene. Last, within the complex Malagasy region made of a mosaic of continental and oceanic islands located close to the African continent, we showed that

  2. [Epidemiology of toxoplasmosis in Chile. V. Prevalence of the infection in humans and domestic and wild animals, studied by indirect hemagglutination reaction, in the Juan Fernández Archipelago. V Region].

    Science.gov (United States)

    Stutzin, M; Contreras, M C; Schenone, H

    1989-01-01

    A serological study utilizing an indirect hemagglutination test (IHAT) for toxoplasmosis was carried out in 222 humans and in 58 domestic animals (31 dogs, Canis familiaris; 27 cats, Felis catus), and in 62 wild mammals distributed into 50 rabbits, Oryctolagus cuniculus and 12 goats, Capra hircus. This survey was performed in the Juan Fernández Archipelago, formed by three islands: Robinson Crusoe, Santa Clara and Alejandro Selkirk (80 degrees 47'-78 degrees 47' west long., and 33 degrees 36'-33 degrees 47' south lat.). Blood samples were collected in filter paper and IHAT with titres greater than or equal to 1:16 were considered positive. This survey showed a prevalence of 42.3% in humans with no difference between men (43.0%) and women (41.5%). A high prevalence was found within groups of young individuals (0 to 19 years old), men and women. Regarding the domestic animal population, 44.8% resulted positive, distributed as follows: dogs 9.7% and cats 85.2%. Twenty one percent of wild animals were positive, distributed as follows: rabbits 8.0% and goats 75.0%. The global prevalence of toxoplasmosis in animals (domestic and wild) was 32.5%. All titres in humans and animals were less than or equal to 1:512. Toxoplasmosis is well extended among the human and animal population of the Juan Fernández Archipelago.

  3. La recepción de la teoría cromosómica-mendeliana en España. La contribución de José Fernández Nonídez

    Directory of Open Access Journals (Sweden)

    Pinar, Susana

    1999-06-01

    Full Text Available On this paper I would like to make known the work of José Fernández Nonídez as introductor in Spain of the Mendelian-Chromosome theory developed in Morgan's school. Likewise, I make a especial mention of the training stage of Nonídez in América, I analyce his books Herencia Mendeliana and Variación y herencia, and I give especial mention of his later task as histologist since his return to the United States and until his death.

    Con este estudio se quiere dar a conocer la labor de José Fernández Nonídez como introductor en España de la teoría mendeliano-cromosómica desarrollada en la escuela de Morgan. Asimismo, se hace especial mención de su etapa formativa en América, se analiza el contenido de sus obras Herencia Mendeliana y Variación y herencia, y se informa de su posterior labor investigadora como histólogo tras su vuelta a Estados Unidos y hasta su muerte.

  4. Edge effects on fern community in an Atlantic Forest remnant of Rio Formoso, PE, Brazil Efeitos de borda na comunidade de samambaias em um remanescente de Floresta Atlântica de Rio Formoso, PE, Brasil

    Directory of Open Access Journals (Sweden)

    IAA Silva

    2011-05-01

    Full Text Available We have investigated how edge effects influence the fern community of Jaguarão Forest (08º 35' 49" S and 35º 15' 39" W, located in the district of Rio Formoso, Pernambuco, Brazil. A comparative analysis was made of the interior and edge of the fragment of forest, regarding the richness, abundance and diversity of ferns in the two areas. Six plots of 10 × 20 m were chosen, three in each area. A total of 381 ferns were recorded, which were distributed among 25 species, 17 genera and 12 families. The two areas (edge and interior were found to differ, with distinct relative air humidities and temperatures (p = 0.00254 and p = 0.00019, respectively. The interior showed higher diversity (t = 7.251 and p = 0.018 and richness (t = 6.379 and p = 0.023 than the edge area, but the same abundance (t = 1.728; p = 0.226 as the edge. Regarding the composition of the flora, it was clear that the interior is a habitat completely distinct from the edge with regard to the fern community, given that only one species, Adiantum petiolatum Desv., was common to both environments. It was concluded that the edge effect causes a decrease in richness and abundance of the fern species found in Jaguarão Forest, where the more sensitive species are being replaced by species that are tolerant to the disturbance caused by the creation of an edge.Este trabalho verificou como os efeitos de borda influenciam as comunidades de pteridófitas presentes na Mata do Jaguarão (08º 35' 49" S e 35º 15' 39" W, município de Rio Formoso, Pernambuco. O estudo foi feito através de análise comparativa entre os ambientes de interior e de borda. Para verificar a riqueza, abundância e diversidade das pteridófitas nos dois ambientes, foram estabelecidas seis parcelas de 10 × 20 m (200 m², sendo três para cada ambiente. Foram contabilizados 381 indivíduos de pteridófitas, distribuídos em 25 espécies, 17 gêneros e 12 famílias. Os dois ambientes (interior e borda caracterizaram

  5. RESEÑA DE: García Fernández, Ernesto y Bonachía Hernando, Juan Antonio (eds., Hacienda, mercado y poder al Norte de la Corona de Castilla en el tránsito del Medievo a la Modernidad.

    Directory of Open Access Journals (Sweden)

    Ana María Rivera Medina

    2016-06-01

    Full Text Available RESEÑA DE:: García Fernández, Ernesto y Bonachía Hernando, Juan Antonio (eds., Hacienda, mercado y poder al Norte de la Corona de Castilla en el tránsito del Medievo a la Modernidad. Valladolid, Castilla Ediciones, 2015, 527 págs. isbn: 978-84-96186-97-2.

  6. Response to the Fernández-Niño Comments on Hernández-Alvarado et al. Increase in Suicide Rates by Hanging in the Population of Tabasco, México between 2003 and 2012. Int. J. Environ. Res. Public Health 2016, 13, 552.

    Science.gov (United States)

    Hernández-Alvarado, Mervyn Manuel; González-Castro, Thelma Beatriz; Tovilla-Zárate, Carlos Alfonso; Fresán, Ana; Juárez-Rojop, Isela E; López-Narváez, María Lilia; Villar-Soto, Mario; Genis-Mendoza, Alma

    2016-07-01

    We thank the comments of Fernández-Niño [1] addressing our article [2] "Increase in Suicide Rates by Hanging in the Population of Tabasco, Mexico between 2003 and 2012", which pointed out that the use of the epidemiological concept "prevalence" is not correctly applied in the present manuscript.

  7. Response to the Fernández-Niño Comments on Hernández-Alvarado et al. Increase in Suicide Rates by Hanging in the Population of Tabasco, México between 2003 and 2012. Int. J. Environ. Res. Public Health 2016, 13, 552

    Directory of Open Access Journals (Sweden)

    Mervyn Manuel Hernández-Alvarado

    2016-07-01

    Full Text Available We thank the comments of Fernández-Niño [1] addressing our article [2] “Increase in Suicide Rates by Hanging in the Population of Tabasco, Mexico between 2003 and 2012”, which pointed out that the use of the epidemiological concept “prevalence” is not correctly applied in the present manuscript.

  8. 28. Fern Canyon (Meier 1979)

    Science.gov (United States)

    Sheauchi Cheng

    2004-01-01

    This established RNA is on the San Dimas Experimental Forest, within the Angeles National Forest. It is approximately 6 miles (10 km) N. of the city of Claremont. It occupies portions of seven sects. in T1N, R8W SBBM (34°12'N., 117°43'W.), USGS Mt. Baldy quad (fig. 58). Ecological subsection – San Gabriel Mountains (M261Bd).

  9. Pteridófitas de Santa Catarina: um olhar sobre os dados do Inventário Florístico Florestal de Santa Catarina, Brasil Ferns and Fern allies from Santa Catarina State: a "look at the data" from Santa Catarina Floristic Forest Inventory, Brazil

    Directory of Open Access Journals (Sweden)

    André Luís de Gasper

    2012-06-01

    Full Text Available Uma das unidades federativas com melhor conhecimento de sua flora, Santa Catarina é o primeiro estado a concluir o Inventário Florístico Florestal na atualidade. Coberto por Floresta Ombrófila Densa, Floresta Ombrófila Mista, Floresta Estacional Decidual e formações associadas, possui grande riqueza de espécies. Este trabalho visa apresentar as espécies de pteridófitas coletadas nas 563 unidades amostrais visitadas. Ao todo 324 espécies foram registradas, das quais 300 são samambaias e 24, licófitas. Estas pertencem a 29 famílias e 94 gêneros, sendo as famílias com maior riqueza específica Polypodiaceae (48 espécies, Pteridaceae (42 e Dryopteridaceae (38. Os gêneros com maior diversidade de espécies foram Asplenium e Thelypteris, com 27 espécies, seguido por Blechnum com 15. Destacam-se ainda 75 espécies consideradas endêmicas para o bioma. 18 registros novos para a flora de Santa Catarina foram feitos. A distribuição por região fitoecológica é a que segue: 288 espécies para a Floresta Ombrófila Densa (128 exclusivas desta região fitoecológica, 177 para a Floresta Ombrófila Mista (30 exclusivas e 57 para a Floresta Estacional Decidual (três exclusivas. Foram registradas ainda 17 espécies para a restinga. Destaca-se a importância do registro de Asplenium lacinulatum, espécie coletada em área de intensa exploração imobiliária e novo registro para Santa Catarina e Alansmia senilis primeiro registro para o Sul do Brasil.Santa Catarina is the first Brazilian state to complete its Forest and Floristic Inventory, and is considered one of the states with a well-known flora. This region is covered by evergreen tropical rain forest, Araucaria forest, seasonal deciduous forest and associated ecosystems, and shows high species richness. This paper presents a list of ferns collected in 563 sampling units. Altogether, 324 species were recorded (300 ferns and 24 lycophytes, which belong to 29 families and 94 genera. The

  10. Fernández de Oviedo (Historia General y Natural de las Indias, Libro VI, cap. LI y la etología clásica

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    Lens-Tuero, Jesús

    1997-06-01

    Full Text Available Not available.

    El presente trabajo se propone llamar la atención sobre un notable texto de Fernández de Oviedo (Historia General y Natural de las Indias, Libro VI, cap. LI que, en la medida que conocemos, no ha sido objeto de un comentario adecuado. En dicho texto se refiere el establecimiento de un pacto entre el hombre y el animal para asegurarse la supervivencia y mutuo beneficio, y la transformación de tal pacto en una relación de amistad y afecto. Tales relaciones pueden ser iluminadas desde la antropología clásica, en la que dichas categorías desempeñaron un papel no carente de relevancia.

  11. Medicina y botánica en las empresas de reyes y caballeros recogidas por Gonzalo Fernández de Oviedo en «Batallas y Quinquagenas»

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    Andrea Maceiras Lafuente

    2015-03-01

    Full Text Available Batallas y Quinquagenas, by Gonzalo Fernández de Oviedo, is one of the most important device´s corpus in Spanish language of the moment. All the devices of this work are authentic, that is, they were used by kings and knights to flaunt politic, loving or religious ideals between the XVth and XVIth centuries. The topics of the devices are as varied as their owners. Nevertheless, the topics associated with medicine, zoology or botany knowledge, which are based in classical sources, are especially interesting. Undoubtedly, the devices supported on the curative or prejudicial qualities of very different elements, like garlic or emeralds, make an original and creative mosaic which reflects the way of thinking and feeling of these knights.

  12. Nucleotide sequence of atpB, rbcL, trnR, dedB and psaI chloroplast genes from a fern Angiopteris lygodiifolia: a possible emergence of Spermatophyta lineage before the separation of Bryophyta and Pteridophyta.

    Science.gov (United States)

    Yoshinaga, K; Kubota, Y; Ishii, T; Wada, K

    1992-01-01

    To elucidate the evolutionary relationship between the Spermatophyta, Pteridophyta and Bryophyta, we cloned a fragment of chloroplast DNA from the fern Angiopteris lygodiifolia (Pteridophyta) and determined its nucleotide sequence. The fragment contained the atpB, rbcL, trnR-CCG, dedB and psaI genes. Comparisons of the deduced amino acid and nucleotide sequences of these genes from the three plant groups indicate that Angiopteris sequences are more closely related to those of Bryophyta species (85% identity on average) than to those of seed plants (76% identity on average), supporting a hypothesis that the Bryophyta and Pteridophyta diverged more recently from one another than their common progenitor diverged from that of the Spermatophyta.

  13. La traducción del Inferno de Pedro Fernández de Villegas: la huella de la tradición poética castellana y de los comentarios a la Commedia de Dante

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    Marfany, Marta

    2015-06-01

    Full Text Available At the turn of the sixteenth century, the archdeacon of Burgos cathedral Pedro Fernández de Villegas undertook a translation of Dante’s Inferno in coplas de arte mayor. Commissioned by Juana de Aragon –Fernando el Católico’s natural daughter–, this translation was printed in 1515 and was accompanied with a commentary. The article discusses the main features of the translation, which are analysed in the light of the Spanish poetic tradition (especially Juan de Mena and of the medieval exegetical tradition of Dante’s work (Cristoforo Landino, L’Ottimo commento or Benvenuto da Imola. A portray of Juana de Aragon, mandator and recipient of the translation, is also provided.A comienzos del siglo XVI, el arcediano de la catedral de Burgos Pedro Fernández de Villegas llevó a cabo, por encargo de Juana de Aragón –hija natural de Fernando el Católico–, una traducción en coplas de arte mayor del Inferno de Dante, que fue impresa en 1515 acompañada de un comentario. El artículo presenta las principales características de la traducción, que se explican a la luz de la tradición poética castellana (especialmente Juan de Mena y de la tradición exegética medieval de la obra de Dante (Cristoforo Landino, L’Ottimo commento o Benvenuto da Imola. Secundariamente, también se ofrece una visión general sobre la figura de Juana de Aragón, comandataria y destinataria de la traducción.

  14. RESEÑA de: Álvarez Fernández, María y Beltrán Suárez, Soledad, Vivienda, gestión y mercado inmobiliarios en Oviedo en el tránsito de la Edad Media a la modernidad. El patrimonio urbano del cabildo catedralicio.

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    Roberto J. González Zalacaín

    2016-06-01

    Full Text Available Reseña de: Álvarez Fernández, María y Beltrán Suárez, Soledad, Vivienda, gestión y mercado inmobiliarios en Oviedo en el tránsito de la Edad Media a la modernidad. El patrimonio urbano del cabildo catedralicio. Bilbao. Servicio Editorial de la UPV/EHU, 2015. 220 págs. isbn: 978-84-9082-140-4.

  15. Propagação de pteridófitas in vitro e in vivo através de esporos Fern propagation in vitro and in vivo from spores

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    Flávia Próspero Borelli

    1990-01-01

    Full Text Available Sujeitas ao processo de extinção, em decorrência do extrativismo, as samambaias arbóreas Dicksonia sellowana (Presl. Hook e Cyathea schanschin Mart, das quais se obtémo xaxim, são espécies ainda pouco estudadas quanto à propagação. Com o objetivo de desenvolver um método adequado à propagação destas espécies, através de esporos, realizaram-se experimentos in vitro e in vivo. Para a desinfecção dos esporos, utilizaram-se soluções de hipoclorito de cálcio, em diferentes concentrações, ou de sódio, comparando-se sua eficiência. Para o cultivo in vitro, empregaram-se os meios nutritivos de Murashige e Skoog modificado e de Jones e a solução de Knop modificada. Na cultura in vivo utilizaram-se xaxim, estagno, terriço ou tijolo fragmentado. Como condições de cultivo, manteve-se a temperatura a 25 ±1°C e o fotoperíodo de 16 horas. Apesar da elevada contaminação durante o processo de germinação in vitro e in vivo, a desinfecção com hipoclorito de cálcio a 2% foi mais eficiente. Os esporos germinaram em 4 a 8 semanas e os prótalos formaram-se após 30 a 40 dias. Obteve-se maior percentagem de germinação e formação de prótalos com os meios de Jones e Knop, bem como xaxim e esfagno, e a germinação de esporos ocorreu mais rapidamente na ausência de esporângios.The objective of this experiment was to study the fern propagation from spores of Cyathea schanschin Mart and Dicksonia sellowiana (Presl. Hook. The spores were decontaminated in calcium or sodium hypochlorite solutions. The in vitro experiments were performed with the media: MS modified, Jones or Knop's solution modified. Tree-fern fibre, sphagnum moss, loam soil or brick peaces were, used for the in vivo experiments. The temperature was mantained at 25 ± 1°C and 16 hours of photoperiod for both treatments (In vivo and in vitro cultures. Besides the high percentage of contamination during the germination process, in vitro and in vivo, the best

  16. How biophysical interactions associated with sub- and mesoscale structures and migration behavior affect planktonic larvae of the spiny lobster in the Juan Fernández Ridge: A modeling approach

    Science.gov (United States)

    Medel, Carolina; Parada, Carolina; Morales, Carmen E.; Pizarro, Oscar; Ernst, Billy; Conejero, Carlos

    2018-03-01

    The Juan Fernández Ridge (JFR) is a chain of topographical elevations in the eastern South Pacific (∼33-35°S, 76-81.5°W). Rich in endemic marine species, this ridge is frequently affected by the arrival of mesoscale eddies originating in the coastal upwelling zone off central-southern Chile. The impacts of these interactions on the structure and dynamics of the JFR pelagic system have, however, not been addressed yet. The present model-based study is focused on the coupled influence of mesoscale-submesoscale processes and biological behavior (i.e., diel vertical migration) on the horizontal distribution of planktonic larvae of the spiny lobster (Jasus frontalis) around the JFR waters. Two case studies were selected from a hydrodynamic Regional Ocean Modeling System to characterize mesoscale and submesoscale structures and an Individual-based model (IBM) to simulate diel vertical migration (DVM) and its impact on the horizontal distribution and the patchiness level. DVM behavior of these larvae has not been clearly characterized, therefore, three types of vertical mechanisms were assessed on the IBM: (1) no migration (LG), (2) a short migration (0-50 m depth, DVM1), and (3) a long migration (10-200 m depth, DVM2). The influence of physical properties (eddy kinetic energy, stretching deformation and divergence) on larval aggregation within meso and submesoscale features was quantified. The patchiness index assessed for mesoscale and submesoscale structures showed higher values in the mesoscale than in the submesoscale. However, submesoscale structures revealed a higher accumulation of particles by unit of area. Both vertical migration mechanisms produced larger patchiness indices compared to the no migration experiment. DVM2 was the one that showed by far the largest aggregation of almost all the aggregation zones. Larval concentrations were highest in the submesoscale structures; these zones were characterized by low eddy kinetic energy, negative stretching

  17. Differences in the photosynthetic plasticity of ferns and Ginkgo grown in experimentally controlled low [O2]:[CO2] atmospheres may explain their contrasting ecological fate across the Triassic-Jurassic mass extinction boundary.

    Science.gov (United States)

    Yiotis, C; Evans-Fitz Gerald, C; McElwain, J C

    2017-06-01

    Fluctuations in [CO 2 ] have been widely studied as a potential driver of plant evolution; however, the role of a fluctuating [O 2 ]:[CO 2 ] ratio is often overlooked. The present study aimed to investigate the inherent physiological plasticity of early diverging, extant species following acclimation to an atmosphere similar to that across the Triassic-Jurassic mass extinction interval (TJB, approx. 200 Mya), a time of major ecological change. Mature plants from two angiosperm ( Drimys winteri and Chloranthus oldhamii ), two monilophyte ( Osmunda claytoniana and Cyathea australis ) and one gymnosperm ( Ginkgo biloba ) species were grown for 2 months in replicated walk-in Conviron BDW40 chambers running at TJB treatment conditions of 16 % [O 2 ]-1900 ppm [CO 2 ] and ambient conditions of 21 % [O 2 ]-400 ppm [CO 2 ], and their physiological plasticity was assessed using gas exchange and chlorophyll fluorescence methods. TJB acclimation caused significant reductions in the maximum rate of carboxylation ( V Cmax ) and the maximum electron flow supporting ribulose-1,5-bisphosphate regeneration ( J max ) in all species, yet this downregulation had little effect on their light-saturated photosynthetic rate ( A sat ). Ginkgo was found to photorespire heavily under ambient conditions, while growth in low [O 2 ]:[CO 2 ] resulted in increased heat dissipation per reaction centre ( DI o / RC ), severe photodamage, as revealed by the species' decreased maximum efficiency of primary photochemistry ( F v / F m ) and decreased in situ photosynthetic electron flow ( Jsitu ). It is argued that the observed photodamage reflects the inability of Ginkgo to divert excess photosynthetic electron flow to sinks other than the downregulated C 3 and the diminished C 2 cycles under low [O 2 ]:[CO 2 ]. This finding, coupled with the remarkable physiological plasticity of the ferns, provides insights into the underlying mechanism of Ginkgoales' near extinction and ferns' proliferation as

  18. Relationships and genetic consequences of contrasting modes of speciation among endemic species of Robinsonia (Asteraceae, Senecioneae) of the Juan Fernández Archipelago, Chile, based on AFLPs and SSRs.

    Science.gov (United States)

    Takayama, Koji; López-Sepúlveda, Patricio; Greimler, Josef; Crawford, Daniel J; Peñailillo, Patricio; Baeza, Marcelo; Ruiz, Eduardo; Kohl, Gudrun; Tremetsberger, Karin; Gatica, Alejandro; Letelier, Luis; Novoa, Patricio; Novak, Johannes; Stuessy, Tod F

    2015-01-01

    This study analyses and compares the genetic signatures of anagenetic and cladogenetic speciation in six species of the genus Robinsonia (Asteraceae, Senecioneae), endemic to the Juan Fernández Islands, Chile. Population genetic structure was analyzed by amplified fragment length polymorphism (AFLP) and microsatellite (simple sequence repeat, SSR) markers from 286 and 320 individuals, respectively, in 28 populations. Each species is genetically distinct. Previous hypotheses of classification among these species into subgenera and sections, via morphological, phytochemical, isozymic and internal transcribed spacer (ITS) data, have been confirmed, except that R. saxatilis appears to be related to R. gayana rather than R. evenia. Analysis of phylogenetic results and biogeographic context suggests that five of these species have originated by cladogenesis and adaptive radiation on the older Robinson Crusoe Island. The sixth species, R. masafuerae, restricted to the younger Alejandro Selkirk Island, is closely related to and an anagenetic derivative of R. evenia from Robinson Crusoe. Microsatellite and AFLP data reveal considerable genetic variation among the cladogenetically derived species of Robinsonia, but within each the genetic variation is lower, highlighting presumptive genetic isolation and rapid radiation. The anagenetically derived R. masafuerae harbors a level of genetic variation similar to that of its progenitor, R. evenia. This is the first direct comparison of the genetic consequences of anagenetic and cladogenetic speciation in plants of an oceanic archipelago. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  19. Casa mansión de los Duques de Alburquerque y de los Duques de Fernán Nuñez : historia y evolución

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    Luz Buelga Lastra

    1992-01-01

    Full Text Available En Madrid, la calle de Santa Isabel vivió el ciclo entero de su desarrollo durante los siglos xvii, xviii y xix. Mesonero Romanos en su estudio sobre Madrid decía: «Entramos en pleno distrito de Lavapiés o del Avapiés... porque ambos títulos vienen emblematizando hace tres siglos a la población indígena matritense en el último término de la escala social... Esta parte del pueblo bajo de Madrid, apellidado de Manoleria... linda por su izquierda con la ancha y espaciosa calle de Santa Isabel y las demás traviesas de ésta, y la de Atocha, y aunque pertenecen al mismo distrito, están ya de antiguo formadas de buen caserío y habitadas por clases pudientes. En la primera de ellas hay que notar la moderna casa palacio de los Conde de Cervellón y de Fernán-Núñez, y al extremo de ellas el suntuoso monasterio de religiosas de Santa Isabel».

  20. Reseña de Casas Gómez, Miguel (dir. & Fernández Smith, Gérard (ed. (2005. IX Jornadas de Lingüística

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    Ana Isabel Rodríguez-Piñero Alcala

    2010-11-01

    Full Text Available Normal 0 21 false false false ES X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Se trata de una reseña de Casas Gómez, Miguel (dir. & Fernández Smith, Gérard (ed. (2005. IX Jornadas de Lingüística.

  1. La producción fotográfica escolar de Ezequiel Fernández Santana 100 años después (1915-2015

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    José Soto Vázquez

    2017-01-01

    Full Text Available Recientes estudios han demostrado las interesantes aportaciones de la fotografía escolar al ámbito de la investigación en Historia de la Educación. En este contexto, las fotografías de Ezequiel Fernández Santana, tomadas entre 1915 y 1938, constituyen un hito en la historia de la fotografía escolar de España. Los cristales originales fueron hallados en un vertedero, después fueron restaurados y digitalizados, según los criterios contemporáneos para fondos documentales, así como catalogados para su correcta identificación, cronología, y tema. Su conservación actual permitirá el estudio de la fotografía escolar con fines artísticos y propagandísticos, dado que estos materiales constituyen un ejemplo único en este sentido. El corpus supone un material inédito y exclusivo, no solo por proceder de un mismo fotógrafo, sino también por su cantidad (220 imágenes, su unidad temática, y su perspectiva pedagógica. De este modo se aúna en su figura el valor de la fotografía tomada in media res por el mismo maestro.

  2. Enemigos declarados de nuestro sistema. La acción política contrarrevolucionaria de Diego de Agüero y Miguel Fernández de Agüero [1770-1816

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    Mariano Martín Schlez

    2011-11-01

    Full Text Available This article analizes the counter-revolutionary social force of the late colonial Buenos Aires. It takes as observables two of the principal leaders: the monopolistic spanish merchants Diego de Agüero and Miguel Fernández de Agüero. The Agüero had a definite political strategy: to oppose to the revolutionary process and to defend the colonial order. This program was constructed throughout more than thirty years, in which they pass from a reformist alliance to face politically and militarily against the revolutionaries. In this trajectory, the confrontations about the traffic of leather with foreign nations turn out to be a hinge, defending the legal trade for the route of Cadiz, arguing that it's Monarchy's bastions. The above mentioned program is link with its social reproduction, based on a political privilege granted by the colonial State. It destruction, by the action of the Revolution, will produce it commercial, political and military defeat

  3. Dryopteris × orexpansa, un nuevo híbrido y D. × deweberi en Cantabria [Dryopteris × oroexpansa, a new hybrid fern and Dryopteris × dewe-veri in Cantabria (N Spain

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    Francisco Javier Pérez Carro

    2013-05-01

    Full Text Available RESUMEN: Se describe un nuevo híbrido en Cantabria Dryopteris × orexpansa. Se presenta su citología y se estudian los caracteres morfológicos y micromorfológicos con el fin de establecer sus posibles parentales: D. oreades y D. expansa. Por otro lado se cita por primera vez en Cantabria, Dryopteris × deweveri.Se hacen algunas consideraciones sobre su distribución en la Península Ibérica y se proporciona información para su identificación. ABSTRACT: Dryopteris × oroexpansa, a new hybrid fern and Dryopteris × dewe-veri in Cantabria (N Spain. A new Dryopteris hybrid from Cantabria is described as D. orexpansa. We report on its cytology and on morphological and micromorphological characters that were studied in order to establish its putative parents: Dryopteris oreades and D. expansa. On the other hand, we record for fist time D. × deweveri from Cantabria (Spain. Some considerations do on his distribution in the Iberian Peninsula and information is provided for his identification.

  4. Ethos y legitimación política en los discursos de asunción de la presidente argentina Cristina Fernández de Kirchner

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    María Alejandra Vitale

    2013-01-01

    Full Text Available En el marco del análisis del discurso político que recupera la noción retórica de ethos y mediante el empleo de una metodología cualitativa, el artículo tiene el propósito de caracterizar las imágenes de sí que Cristina Fernández de Kirchner construyó en sus discursos de asunción como medio de legitimación de liderazgo político. Se trata de lo que hemos denominado ethos pedagógico-experto y, retomando análisis previos sobre el discurso presidencial de Néstor Kirchner, ethos militante. El primero responde a una escenografía profesoral donde la presidente argentina se posiciona como una profesora que da clase a sus alumnos, generada por el uso de procedimientos característicos del discurso explicativo. El ethos militante se corresponde con la violación de ciertas convenciones propias del género discurso de asunción y le permite identificarse con la figura y el gobierno de Néstor Kirchner. El ethos pedagógico-experto, por su parte, la ayuda a construir una identidad propia.

  5. Pespectivas y planteamientos de una poética: reflexiones sobre poesía y ficción en el comentario a la Divina Comedia de Fernández de Villegas

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    Cinthia M. Hamlin

    2012-01-01

    Full Text Available En 1515 se difunde en Burgos la primera traducción impresa de la Divina Comedia, edición que contaba con una exhaustiva glosa rodeando cada copla en la que Pedro Fernández de Villegas traducía y amplificaba, a su vez, el “Comento sopra la Comedia” de Landino (1481. En el siguiente trabajo analizaremos las reflexiones sobre poesía y ficción presentes en el comentario, con el objetivo de ponerlas en relación, por un lado, con el Prólogo de Landino y, por otro, con algunas de las concepciones poéticas más importantes del Humanismo peninsular. Adelantamos a manera de conclusión que la particular situación enunciativa desde la que escribe el arcediano, a saber, su calidad de religioso y literato de corte, le confiere a su texto un valor indiscutible en cuanto exponente de las problemáticas culturales más apremiantes del período, en especial la tensión entre la Escolástica y el Humanismo, que su mismo texto, en sus posturas un tanto contradictorias, encarna. Sin embargo, su valor mayor radica en la vital importancia que presenta para la historia de las reflexiones literarias en la Península, pues al mismo tiempo que releva y reformula toda la serie de reflexiones poéticas y tópicos literarios que encuentra en su tradición, presenta actitudes que, a comienzos del siglo XVI, resultan novedosas.La première traduction castillane imprimée de la Divina Commedia (Burgos, 1515 fut accompagnée d'un commentaire exhaustif entourant chaque strophe, dans lequel Pedro Fernández de Villegas a traduit et amplifié le “Comento soprala Commedia” (1481 de Cristoforo Landino. L'objectif du présent article est d'analyser les réflexions concernant la poésie et la fiction que propose le commentaire, afin de les mettre en relation, d'une part, avec le prologue de Landino et, d'autre part, avec certaines des principales conceptions poétiques de l'Humanisme péninsulaire. En guise de conclusion, nous pouvons avancer que la situation

  6. Fern-synthesized nanoparticles in the fight against malaria: LC/MS analysis of Pteridium aquilinum leaf extract and biosynthesis of silver nanoparticles with high mosquitocidal and antiplasmodial activity.

    Science.gov (United States)

    Panneerselvam, Chellasamy; Murugan, Kadarkarai; Roni, Mathath; Aziz, Al Thabiani; Suresh, Udaiyan; Rajaganesh, Rajapandian; Madhiyazhagan, Pari; Subramaniam, Jayapal; Dinesh, Devakumar; Nicoletti, Marcello; Higuchi, Akon; Alarfaj, Abdullah A; Munusamy, Murugan A; Kumar, Suresh; Desneux, Nicolas; Benelli, Giovanni

    2016-03-01

    Malaria remains a major public health problem due to the emergence and spread of Plasmodium falciparum strains resistant to chloroquine. There is an urgent need to investigate new and effective sources of antimalarial drugs. This research proposed a novel method of fern-mediated synthesis of silver nanoparticles (AgNP) using a cheap plant extract of Pteridium aquilinum, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Phytochemical analysis of P. aquilinum leaf extract revealed the presence of phenols, alkaloids, tannins, flavonoids, proteins, carbohydrates, saponins, glycosides, steroids, and triterpenoids. LC/MS analysis identified at least 19 compounds, namely pterosin, hydroquinone, hydroxy-acetophenone, hydroxy-cinnamic acid, 5, 7-dihydroxy-4-methyl coumarin, trans-cinnamic acid, apiole, quercetin 3-glucoside, hydroxy-L-proline, hypaphorine, khellol glucoside, umbelliferose, violaxanthin, ergotamine tartrate, palmatine chloride, deacylgymnemic acid, methyl laurate, and palmitoyl acetate. In DPPH scavenging assays, the IC50 value of the P. aquilinum leaf extract was 10.04 μg/ml, while IC50 of BHT and rutin were 7.93 and 6.35 μg/ml. In mosquitocidal assays, LC50 of P. aquilinum leaf extract against Anopheles stephensi larvae and pupae were 220.44 ppm (larva I), 254.12 ppm (II), 302.32 ppm (III), 395.12 ppm (IV), and 502.20 ppm (pupa). LC50 of P. aquilinum-synthesized AgNP were 7.48 ppm (I), 10.68 ppm (II), 13.77 ppm (III), 18.45 ppm (IV), and 31.51 ppm (pupa). In the field, the application of P. aquilinum extract and AgNP (10 × LC50) led to 100 % larval reduction after 72 h. Both the P. aquilinum extract and AgNP reduced longevity and fecundity of An. stephensi adults. Smoke toxicity experiments conducted against An. stephensi adults showed that P. aquilinum leaf-, stem-, and root-based coils

  7. Arsenic phytoextraction and hyperaccumulation by fern species Fitoextração e hiperacumulação de arsênio por espécies de samambaias

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    Maria Isidoria Silva Gonzaga

    2006-02-01

    Full Text Available Arsenic (As is an ubiquitous trace metalloid found in all environmental media. Its presence at elevated concentrations in soils derives from both anthropogenic and natural inputs. Arsenic is a toxic and carcinogenic element, which has caused severe environmental and health problem worldwide. Technologies currently available for the remediation of arsenic-contaminated sites are expensive, environmentally disruptive, and potentially hazardous to workers. Phytoextraction, a strategy of phytoremediation, uses plants to clean up contaminated soils and has been successfully applied to arsenic contaminated soils. It has the advantage of being cost-effective and environmentally friendly. A major step towards the development of phytoextraction of arsenic-impacted soils is the discovery of the arsenic hyper accumulation in ferns, first in Pteris vittata, which presented an extraordinary capacity to accumulate 2.3% arsenic in its biomass. Another fern, Pityrogramma calomelanos was found to exhibit the same hyperaccumulating characteristics. After that, screening experiments have revealed that the Pteris genus is really unique in that many species have the potential to be used in phytoextraction of arsenic. In general, these plants seem to have both constitutive and adaptive mechanisms for accumulating or tolerating high arsenic concentration. In the past few years, much work has been done to understand and improve the hyperaccumulating capability of these amazing plants. In particular, the field of molecular biology seems to hold the key for the future of the phytoremediation.O arsênio e um metalóide traço encontrado basicamente em todos os ambientes. Elevadas concentrações de arsênio no solo podem acontecer naturalmente devido ao intemperismo de rochas ricas em arsênio, como também de atividades antropogênicas. O arsênio é um elemento tóxico e cancerígeno. Em muitas partes do mundo, a contaminação pelo arsênio tem causado problemas

  8. Neoplasias do trato alimentar superior de bovinos associadas ao consumo espontâneo de samambaia (Pteridium aquilinum Neoplasms of the upper digestive tract of cattle associated with spontaneous ingestion of bracken fern (Pteridium aquilinum

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    Marione A. Moreira Souto

    2006-06-01

    /orofaringe, epiglote, média (terços cranial, médio e caudal do esôfago e caudal (entrada do rúmen e rúmen do TAS, observou-se que a localização era cranial em 39% dos casos, média em 16%, e caudal em 45%. Utilizando-se esse mesmo critério de agrupamento, porém considerando o número total de vezes em que CCEs (de tamanhos variados foram diagnosticados nas regiões cranial, média e caudal, os números alteraram-se para 34, 26 e 40%, respectivamente. As evidências epidemiológicas e histomorfológicas relatadas neste estudo reforçam as observações de uma estreita correlação entre a infecção pelo papiloma-vírus bovino tipo 4, causador da papilomatose digestiva, e a co-carcinogênese química dos princípios tóxicos da samambaia na patogênese dos CCEs do TAS de bovinos. Entretanto, a presença de alterações pré-neoplásicas (áreas de displasia, áreas de CCE in situ ou CCEs em estágios iniciais de desenvolvimento, independentemente da presença de papilomas no local, mostram claramente ser possível o desenvolvimento de CCEs diretamente do epitélio normal, possivelmente por uma ação direta dos carcinó-genos químicos da samambaia.Thirty bovine with neoplasms of the upper digestive tract (UDT associated with spontaneous ingestion of bracken fern (Pteridium aquilinum were studied. They were from 27 farms, located in the municipalities of Jaguari (23 and Nova Esperança do Sul (4, Rio Grande do Sul, Brazil. The total cattle population in those farms was 1,090 and large amounts of bracken fern were found in the pastures. Twenty-six of the affected cattle were cows and four were castrated males, 3-13 years of age; most of them were 7-8 years old (46,6%. Clinical signs observed in the affected animals were progressive weight loss, absence of ruminal movements, cough, dysphagia, regurgitation, halitosis, diarrhea, and bloat. Less frequent signs were selective appetite, dyspnea, and salivation. Two bovine died and 28 were submitted to euthanasia in advanced stage

  9. {sup 13}C NMR, micro-FTIR and fluorescence spectra and pyrolysis-gas chromatograms of coalified foliage of late Carboniferous medullosan seed ferns, Nova Scotia, Canada: implications for coalification and chemotaxonomy

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, P.C.; Orem, W.H.; Mastalerz, M.; Zodrow, E.L.; Vieth-Redemann, A.; Bustin, R.M. [US Geological Survey, Reston, VA (United States)

    1995-03-01

    The cuticles and cuticle-free compression of three Carboniferous medullosan seed-fern leaf species ({ital Macroneuropteris scheuchzeri}, {ital Neuropteris ovata} var. {ital simonii} and {ital Alethopteris lesquereuxii}) were analyzed by elemental, {sup 13}C nuclear magnetic resonance (NMR), micro-FTIR (Fourier transform infrared) and coal petrographic techniques. The {sup 13}C NMR spectra of the cuticle-free compression and the associated whole coal are generally similar and consist of a large aromatic carbon peak, a smaller aliphatic carbon peak and a shoulder on the aromatic peak, representing phenolic carbons. In contrast, the {sup 13}C NMR spectra of the cuticles from the same leaves have a predominant peak for aliphatic carbons and a much smaller aromatic carbon peak. Micro-FTIR spectra of the cuticles show oxygenated functional groups (carboxyl and ketone) similar to those in modern cuticles. The cuticle-free compressions (mainly vitrinite), in turn, show the absence or significant reduction in oxygenated functional groups. Fluorescence spectra for the cuticles from all these species show a great similarity with a {lambda}{sub max} at 580-590 nm, which is consistent with the similar vitrinite reflectance (R{sub r}) and H/C and O/C ratios of the cuticle-free compressions. These results indicate that leaf cuticle-free compressions, which were initially cellulose rich, can alter, during peatification and coalification, to a macromolecular structure similar to that of coalified wood. Thus, a lignin-enriched structure is not a prerequisite for the formation of the macromolecular structure of vitrinite. The micro-FTIR data reveal some significant differences among the cuticles that may be of chemotaxonomic value. Clearly,a combination of macro- and micro-techniques offers a better basis for the interpretation of the molecular structure of pre-macerals and their alteration during peatification and coalification. 55 refs., 11 figs., 4 tabs.

  10. «God save us from more revolutions»: the Aranjuez Mutiny and the Dos de Mayo uprising in the light of Count Fernán Núñez’s widow | «Dios nos libre de más revoluciones»: el Motín de Aranjuez y el Dos de Mayo vistos por la condesa viuda de Fernán Núñez

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    Antonio Calvo Maturana

    2011-12-01

    Full Text Available This essay’s objective is to analyse a direct and unpublished testimony of the two biggest Spanish historical events of 1808: the Mutiny of Aranjuez and Dos de Mayo Uprising. With this purpose we present to the public a collection of letters written by Maria Esclavitud Sarmiento, Countess of Fernan Nuñez, and found in the French National Archives of Paris. In this lady’s correspondence we can appreciate the fears, the hopes and the speculations lived and suffered by the people from Madrid during this period. Thanks to this source we have access to the impressions of an eyewitness (a woman, something even more interesting and unusual who was in constant relation with the current situation, gathering news and rumours, sometimes already obsolete in the next letter because of the frenetic political situation. By her contacts with well-informed people (such as her son, the count of Fernan Nuñez, or members of government like Pedro Cevallos or Eusebio Bardaji, the widow countess offers interesting information about the most important figures and events of this year: Ferdinand VII (his rise to the throne and the preparation for his trip to Bayonne, Napoleon (his arrival to Spain and his recognition, or not, of the new king, Manuel Godoy (his imprisonment and his delivery to French authorities, Charles IV (the renounce of his claim and his posterior regret and Marie Louise of Parme (many rumours related to her dark legend. | El objetivo de este trabajo es ofrecer al lector un testimonio directo e inédito de lo acontecido en Madrid durante los dos grandes hitos históricos españoles de 1808: el Motín de Aranjuez y el Dos de Mayo. Para ello utilizaremos principalmente unas cartas de María Esclavitud Sarmiento, condesa viuda de Fernán Núñez, encontradas en los Archivos Nacionales de París. Esta dama de la alta nobleza reflejó en su correspondencia los miedos, esperanzas y especulaciones que asaltaron a la sociedad madrileña del momento. De

  11. Cattle acute intoxication by bracken fern ( Pteridium aquilinum, L. Kuhn at north Paraná State-Brazil/ Ocorrência de intoxicação aguda em bovinos pela samambaia ( Pteridium aquilinum, L. Kuhn no norte do Paraná-Brasil

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    Alexandre Amorim Monteiro

    2001-05-01

    Full Text Available The authors describe a case of acute intoxication by bracken fern ( Pteridium aquilinum in a cattle herd raised in the city of Reserva, Parana State. A total of 25 animals died due to intoxication caused by the ingestion of large amounts of the toxic plant after the occurrence of a frost period in the winter month of July, 2000. Beside the herd clinical case, the authors present some considerations about the spreading of bracken fern in Parana, with particular interest in the environmental conditions (including weather. We suspect that these conditions can facilitate the spread of the plant during the cold months of the year. More plant available means a favorable situation for the bracken fern animal consumption, then causing losses to the cattle industry.Os autores descrevem a ocorrência de um surto de intoxicação aguda pela samambaia ( Pteridium aquilinum, L. Kuhn, em bovinos, criados numa propriedade rural localizada no município de Reserva, estado do Paraná. Um total de 25 animais foram a óbito. A ocorrência da intoxicação teve, muito provavelmente, uma relação direta com as freqüentes e acentuadas geadas ocorridas no mês de julho de 2000. Além do relato clínico, os autores apresentam considerações a respeito da proliferação da samambaia no Paraná, destacando condições ambientais e climáticas favorecedoras dessa disseminação, bem como os prejuízos à pecuária e as conseqüências da presença desse vegetal tóxico nas pastagens paranaenses.

  12. Near-shore distribution of phyllosomas of the two only lobster species (Decapoda: Achelata present in Robinson Crusoe Island and endemic to the Juan Fernández archipelago Distribución costera de filosomas de las dos únicas especies de langostas (Decapoda: Achelata presentes en la Isla Robinson Crusoe y endémicas del archipiélago de Juan Fernández

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    ÁLVARO T PALMA

    2011-09-01

    Full Text Available Two lobster species coexist in the southeast Pacific Juan Fernández archipelago, Jasus frontalis (Milne-Edwards, 1837 and Acantharctus delfini (Bouvier, 1909. Like most lobster species they undergo a prolonged larval period, which is particularly long for J. frontalis (> 16 months. Though typical of Palinurids, this long larval duration is usually not thought to be conducive to local recruitment. While it is known that settlement is confined to the three islands of the archipelago (Robinson Crusoe, Alejandro Selkirk and Santa Clara and Desventuradas Islands (aprox. 800 km to the north, it remains poorly understood how local larval supply allows such distribution pattern. The goal of this study is twofold. Firstly, we aimed to characterize the distribution and abundance of the larvae of these two species around Robinson Crusoe Island using plankton tows and systematic hydrographic records between October 2008 to March of 2011, thus providing the first systematic and prolonged coupled biophysical observations in the nearshore of the archipelago. We hypothesize that spatial and temporal larval distribution patterns are associated to their retention around the archipelago, thus contributing to our knowledge of the physical and biological processes maintaining their extreme isolation. Secondly, using molecular genetics, we confirm a simple taxonomic criteria to distinguish the larvae of the two species, thus aiding future studies of larval dynamics. Throughout phyllosomas of A. delfini were more abundant than that of J. frontalis. Both species were more abundant on the northern shores of Robinson Crusoe Island and generally associated with warmer and saltier waters and mostly present in the samples collected during spring and summer months. Phyllosomas of both species were more abundant during nighttime tows in the upper layer of the water column surveyed suggesting a diurnal vertical migration behavior which, for coastal dwelling meroplanktonic

  13. THE FERN-GENUS PLEOCNEMIA PRESL

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    R. E. HOLTTUM

    2015-11-01

    Full Text Available 1. The genus Pleocnemia Presl is redefined and differentiated from Tectaria- Cav. and Arcypteris Underw., the latter genus being very closely related to Pleocne- mia. 2. The configuration of the perispore proved to be of importance for the characterisation of the .species. In this regard three types are distinguished, perispore 1 forming crisped anastomosing wings, perispore consisting of many slender spines, and, an intermediate type, perispore forming many small separate wings. 3. Tentatively 15 species are recognized. Of these, Pleocnemia winitii Holttum, P. acuminata Holttum, P. pleiotricha Holttum, P. presliana Holttum, P. dimidiolobata Holttum, P. tripinnata Holttum, and P. seranensis Holttum are described as new, aa well as one variety, P. conjugata var. elatior Holttum. 4. The following new combinations are made: P. hemiteliiformis (Racib. Holt- tum (basinym: Pleocnemia leuzeana var. hemiteliaeformis Racib., P. olivacea (Copel. Holttum (basinym: Tectaria olivacea Copel., P. kingii (Copel. Holttum (basinym: Tectaria kingii Copel., and P. chrysotricha (Bak. Holttum (basinym: Nephrodium chrysotrichum Bak.. 5. Reductions to synonymy are: Pleocnemia javanica Presl to P. conjugata (Bl. Presl, and Dictyopteris compitalis v. A. v. R. to P. hemiteliiformis (Racib. Holtt.

  14. Anatomical structure of Polystichum Roth ferns rachises

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    Oksana V. Tyshchenko

    2012-03-01

    Full Text Available The morpho-anatomical characteristics of rachis cross sections of five Polystichum species is presented. The main and auxiliary anatomical features which help to distinguish investigated species are revealed.

  15. Biodiesel Production from Azolla filiculoides (Water Fern ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 13, No 6 (2014) >. Log in or Register to get access to full text downloads.

  16. Biodiesel Production from Azolla filiculoides (Water Fern ...

    African Journals Online (AJOL)

    Results: The presence of myristic acid (C14:0), palmitic acid (C16:0), palmitoleic acid (C16:1), myristic acid (C14:0), stearic acid (C18:3), oleic acid (C18:1) and linoleic acid 9C18:2), eicosenoic acid (C20:1), eicosapentaenoic acid (C20:5), erucic acid (C22:1) and docosahexaenoic acid (C22:6) in the macroalgae biodiesel ...

  17. SURVEY OF ORNAMENTAL FERNS, THEIR MORPHOLOGY AND ...

    African Journals Online (AJOL)

    emblem, bank notes and coins (Patrick and John,. 2000). The business of setting up ornamental gardens has become quite relevant in today's business environments. Some natural factors causing environmental degradation include drought, fire (Baiyewu et al., 2005), clearing of land, erosion from heavy rainfall and ...

  18. USE OF BANANA TREE PSEUDOSTEM ENRICHED WITH NITROGEN AND PHOSPHOROUS AS SUBSTRATE FOR CULTIVATION OF FERNS USO DE PSEUDOCAULE DE BANANEIRA ENRIQUECIDO COM NITROGÊNIO E FÓSFORO COMO SUBSTRATO PARA O CULTIVO DE SAMAMBAIAS

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    Suerlani Aparecida Ferreira Moreira

    2009-12-01

    Full Text Available

    The prohibition of the use of xaxim fiber as substrate, because its raw material source (Dicksonia sellowiana was listed as an endangered species, lead to the need of looking for other kinds of substrate. Banana tree cultivation produces a large amount of pseudostem residues, which, due to their physical-chemical characteristics, can be an alternative in substrates composition for ornamental plants, in substitution for xaxim fiber, mainly when associated with fertilizers. This research aimed to evaluate biomass production, nutritional stage, and nutrients availability for ferns, testing substrates in xaxim fiber (XF and banana tree pseudostem (BP, and fertilizations with N and P. The substrate proportions were sand:soil:XF and sand:soil:BP, in a relation of 1:1:2 in volume. Dosages tested were 0 mg dm-3; 68.5 mg dm-3; 137.0 mg dm-3; 205.5 mg dm-3; and 374.0 mg dm-3 of N and 0 mg dm-3; 97.7 mg dm-3; 195.4 mg dm-3; 291.9 mg dm-3; and 390.8 mg dm-3 of P2O5. The number of leaves produced by the fern did not differ significantly in response to substrates or N and P dosages. The same result was verified in most of the substrate and plant mineral evaluations. It was concluded that banana tree pseudostem could perfectly replace xaxim fiber as substrate component for ferns.

  19. Intoxicação aguda por samambaia (Pteridium aquilinum em bovinos na Região Central do Rio Grande do Sul Acute poisoning by bracken fern (Pteridium aquilinum in cattle in central Rio Grande do Sul, Brazil

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    Bruno L. Anjos

    2008-10-01

    Full Text Available Foram revisados casos de intoxicação por samambaia (Pteridium aquilinum em bovinos de 10 pequenas propriedades rurais de sete municípios da Região Central do Rio Grande do Sul. O estudo abrangeu 6.256 necrospias de bovinos realizadas num período de 43 anos e incluiu 15 necropsias de bovinos que morreram em conseqüência da intoxicação aguda por samambaia. As taxas de morbidade e mortalidade foram 17,9% e a letalidade era virtualmente de 100%. Em 40% das propriedades a doença ocorreu em pequenos surtos afetando vários bovinos; em 60% das propriedades apenas um bovino era afetado. Os principais sinais clínicos incluíam febre (40-42ºC, apatia, salivação e hemorragias, principalmente pelas gengivas, pela cavidade nasal e pelo trato gastrintestinal. Múltiplas petéquias eram observadas nas mucosas e na pele. Ocasionalmente observou-se hematúria e sangue no leite. A doença era invariavelmente fatal após um curso clínico de dois dias. Alterações hematológicas consistiam de leucopenia por neutropenia, anemia normocítica normocrômica e trombocitopenia arregenerativa. Os achados de necropsia incluíam hemorragias de intensidade variável em vários órgãos e infartos no fígado. Tanto as hemorragias quanto os infartos foram confirmados histologicamente; agregados de bacilos e vasos trombosados foram observados em associação com os infartos. Aplasia da medula óssea era um achado consistente nos quatro casos em que esse órgão foi examinado.Cases of acute poisoning by bracken fern (Pteridium aquilinum in cattle from 10 small farms of seven municipalities of the Central Region of Rio Grande do Sul State, Brazil, were reviewed. The study encompassed 6,256 necropsies of cattle considering a 43-year period and included 15 necropsies of cattle dying from acute bracken poisoning. Morbidity and mortality were 17.9% and lethality was virtually 100%. In 40% of the farms the disease occurred in small outbreaks affecting several cattle

  20. Sobre la moderna virtud de pensar en el bien común antes que en el interés propio: el sueño y otros recursos literarios en «los paseos de la verdad» de Fernández de Lizardi

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    M.ª Isabel TERÁN ELIZONDO

    2011-01-01

    Full Text Available En este artículo se estudia la presencia del sueño como elemento narrativo recurrente en la obra de Fernández de Lizardi y, en particular, en Los paseos de la verdad, publicado durante cinco entregas en 1815 en la Alacena de Frioleras, a imitación de los Sueños de torres de Villarroel. Se destaca la voluntad moralizadora del autor y la vinculación del sueño a la constitución de un ideal, el de una nueva nación construida a partir de la síntesis de las mejores ideas que ofrecía su época, ya fueran de la tradición o de la modernidad.

  1. Caracterização etnobotânica dos sistemas de manejo de samambaia-preta (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae utilizados no sul do Brasil Ethnobotanical characterization of leatherleaf fern (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae management systems used in southern Brazil

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    Cristina Baldauf

    2007-12-01

    Full Text Available (Caracterização etnobotânica dos sistemas de manejo de samambaia-preta (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae utilizados no sul do Brasil. A samambaia-preta (Rumohra adiantiformis (G. Forst Ching- Pteridophyta é utilizada comercialmente na produção de arranjos florais. A extração desta espécie é fonte de renda de muitas famílias da região sul do Brasil. O objetivo deste estudo foi caracterizar os sistemas de manejo da espécie utilizados no Estado do Rio Grande do Sul (RS através do uso de entrevistas semi-estruturadas e observação participante com famílias extrativistas do município de Maquiné-RS. Foi verificada a ocorrência de uma grande diversidade de técnicas de manejo, a partir da qual foi proposta uma tipologia de sistemas de manejo. A tipologia consiste em quatro sistemas de manejo principais, de acordo com o manejo da paisagem e das populações de samambaia empregados. Constatou-se uma associação entre a situação fundiária e os sistemas de manejo utilizados. Nas terras arrendadas é realizada apenas a coleta das frondes, enquanto nas terras próprias são realizadas intervenções como podas, derrubadas de árvores, retirada de frondes mortas, pisoteio da área após coleta, além de interação com sistemas de agricultura de coivara e criação de gado. A tipologia dos sistemas de manejo elaborada, em associação com outros estudos sobre a sustentabilidade do extrativismo de samambaia-preta, vem fundamentando a regulamentação desta atividade no Rio Grande do Sul.(Ethnobotanical characterization of leatherleaf fern (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae management systems used in southern Brazil. The leatherleaf fern (Rumohra adiantiformis (G. Forst. Ching is commercially used in flower arrangements. The harvesting of this species is an income source for many families from southern Brazil. The aim of this study was to characterize species management systems used in Maquin

  2. Seamounts in the southeastern Pacific Ocean and biodiversity on Juan Fernandez seamounts, Chile Montes submarinos en el océano Pacífico suroriental y biodiversidad en el cordón de Juan Fernández, Chile

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    Eleuterio Yáñez

    2009-01-01

    Full Text Available Seamounts are vulnerable marine ecosystems. In Chile, information on these ecosystems is quite scarce; thus, a compilation of information on their geographical distribution and biodiversity is presented herein. A total of 118 seamounts distributed in the Chilean EEZ are identified and characterized. Additionally, an in situ assessment was carried out on the Juan Fernandez seamounts 1 and 2 (JF1 and JF2, which were also oceanographically characterized. Phytoplankton, zooplankton, and marine invertebrate samples were collected and an exploratory fishing survey was executed using different gears. According to the bibliographical review, a total of 82 species have been collected on the JF1 and JF2 seamounts, highlighting fmdings of black coral species caught in lobster traps at the Juan Fernandez Archipelago. Submarine images of the marine substrate at JF1 and JF2 reveal characteristics attributable to the impact of bottom dredges, coinciding with the information obtained from the trawling fleet. The fishing activity was carried out primarily at JF2 (4,667 km of trawling. The monthly fishing effort increased considerably in 2002, 2003, and 2005, reaching values above 500 km of trawling and, thus, modifying the spatial structure of the resource aggregates on the JF2 seamount.Los montes submarinos constituyen ecosistemas marinos vulnerables. Chile presenta una escasa información acerca de estos ecosistemas, por lo que este trabajo recopila información sobre distribución geográfica y biodiversidad. Se identifican y caracterizan 118 montes en la ZEE de Chile. Adicionalmente, una evaluación in situ se desarrolló sobre los montes Juan Fernández 1 y 2 (JF1, JF2, caracterizándolos oceanógraficamente. Se recolectaron muestras de fitoplancton, zooplancton e invertebrados marinos, y se realizó pesca exploratoria con diversos artes. La revisión bibliográfica establece que en JF1 y JF2, se han capturado un total de 82 especies, destacándose la

  3. Política 2.0. La comunicación política mediada por Twitter: ¿alternativa o complemento de los medios de comunicación masiva tradicionales? : Estudio de la comunicación política y de sus repercusiones mediáticas centrado en la figura de la Presidenta Cristina Fernández de Kirchner, en el período agosto-octubre de 2011

    OpenAIRE

    Domínguez, Natalia

    2015-01-01

    La presente investigación analizará el uso político de la comunicación 2.0, específicamente de la red de microblogging Twitter. El actor político elegido es la Presidenta de la Nación, Cristina Fernández de Kirchner durante el período agosto de 2011 y octubre de 2011 . Se realizará un análisis sobreconstrucción de la subjetividad política en las redes sociales, las concepciones sobre: la comunicación masiva, el uso de las redes sociales, los debates políticos y la interacción con los usuari...

  4. Rendimientos, estructuras de tallas y madurez sexual del alfonsino (Beryx splendens capturado en el cordón submarino de Juan Fernández, Chile Fishing yields, size structures, and sexual maturity of alfonsino (Beryx splendens caught on Juan Fernandez seamounts, Chile

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    Aurora Guerrero

    2009-01-01

    Full Text Available Se analiza la información recopilada en lances comerciales para la captura de alfonsino (Beryx splendens realizados en montes submarinos del archipiélago de Juan Fernández (Chile, entre los años 2001 y 2003, que corresponden a la etapa de desarrollo inicial de esta pesquería. En dicho período se efectuaron 187 lances, de los cuales en 121 se obtuvo la especie objetivo, capturándose 525,1 ton, que constituyeron el 99,2% de la captura total. Por la configuración irregular de los fondos, los lances de pesca se caracterizaron por su corta duración (0,26-0,50 h, a profundidad media de 469,7 m. En este periodo se analizaron 14.773 ejemplares, 6.064 machos (41% y 8.709 hembras (59%, evidenciando un predominio de hembras. La proporción sexual estructurada a la talla mostró un predominio de machos a tallas inferiores a 24 cm de longitud de horquilla (LH. En machos el tamaño medio fluctuó entre 34,6 y 36,8 cm de LH y en hembras entre 36,2 y 38,4 cm LH. Para determinar la madurez de las gónadas, se utilizó la escala macroscópica propuesta por Lehodey et al. (1997 y se estableció que los machos alcanzaron la primera madurez (TMS50% a 34,3 cm LH y las hembras a los 33,3 cm LH. Los rendimientos promedio en el período analizado correspondieron entre 0,2 y 6,6 ton lance-1 y entre 1,8 y 19,0 ton h.a.-1 , con medias de 4,3 ton lance-1 y 9,2 ton h.a.-1 .We analyzed information collected during commercial hauls targeting alfonsino (Beryx splendens on seamounts of the Juan Fernández Archipelago (Chile from the early stages of the fishery (2001-2003. Of the 187 hauls carried out in this period, 121 were successful; alfonsino catches reached 525.1 ton, constituting 99.2%> of the total catch. Due to the irregularity of the sea bottom, short (0.26-0.50 h fishing hauls were performed at mid-depth (469.7 m. We analyzed 14,773 specimens during the study period: 6,064 males (41% and 8,709 females (59%, the latter being predominan! The size structure was

  5. Conjunto de acciones educativas que contribuyen a la integración de niños con desviaciones afectivo conductuales (t.c a las actividades recreativas comunitarias en el Consejo Popular Ceferino Fernández Viña del municipio Pinar del Río

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    Bárbara María García Machín

    2009-09-01

    Full Text Available La integración de niños con desviaciones afectivo conductuales a las actividades recreativas comunitarias resulta ser una prioridad del sistema social cubano, la realización de una investigación explicativa en el Consejo Popular Ceferino Fernández Viña encaminado a mejorar las dificultades en el comportamiento de niños con este tipo de necesidad educativa especial permite una integración de elementos básicos de la concepción socio histórico cultural en un modelo educativo promotor de modos de comportamiento para propiciar la formación integral. Los alumnos seleccionados de forma intencional, lo formaron un total de 20. En este estudio se emplearon los métodos teóricos histórico y lógico, análisis y síntesis, inducción – deducción dentro e los empíricos observación entrevista, encuesta, y visita al hogar. La propuesta se elabora a partir de la necesidad de integración teniendo en cuenta la caracterización y diagnóstico de las principales dificultades en el comportamiento. El aporte principal de la investigación consiste en variadas actividades que les permita estimular, motivar, desarrollar e interiorizar modos de actuación y comportamiento para su aplicación en la comunidad, permitiéndoles un protagonismo estudiantil. La efectividad de su aplicación radica en la prevención de estas dificultades para contribuir a la formación de un hombre integral.

  6. Entrevista con prof. Noberto Fernández Lamarra: La universidad en Brasil y Argentina en perspectiva comparada: hacia un espacio común Latinoamericano de educación superior en el marco de la internacionalización de la educación

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    Noberto Fernández Lamarra

    2017-07-01

    Full Text Available El profesor Norberto Fernández Lamarra es profesor de posgrado, investigador y consultor nacional e internacional en el área de las políticas, la planificación,  la gestión y la evaluación de la educación –particularmente con perspectiva comparada-, con énfasis en los últimos años en la educación superior.  Actualmente es Director de Posgrados en la Universidad Nacional de Tres de Febrero, en Buenos Aires, Argentina, donde, además, dirige el Núcleo Interdisciplinario de Formación y Estudios para el Desarrollo de la Educación (NIFEDE, el Doctorado en Políticas y Gestión de la Educación Superior y el Programa de Posgrados en Políticas y Administración de la Educación (Maestrías y Especializaciones. Es Presidente de la Sociedad Argentina de Educación Comparada y ha sido Vicepresidente del Consejo Mundial de Sociedades de Educación Comparada, entre los años 2010 y 2016 (UCCES y Presidente fundador de la Sociedad Iberoamericana de Educación Comparada (SIBEC. Dirige las revistas académicas Revista Argentina de Educación Superior (RAES, Revista Latinoamericana de Educación Comparada (RELEC y Revista Latinoamericana de Política y Administración de la Educación (RELAPAE.

  7. Hematologycal, biochemical, Urinary and histopathological changes in natural intoxication in bovine by bracken fern (Pteridium aquilinum (L. Kühn/ Alterações hematológicas, bioquímicas, urinárias e histopatológicas na intoxicação natural em bovinos pela samambaia Pteridium aquilnum (L. Kühn

    Directory of Open Access Journals (Sweden)

    Itacir Eloi Sandini

    2005-06-01

    Full Text Available Enzootic hematuria is a cronic disease of cows clinically characterized by intermittent hematuria that can be caused by bracken fern (Pteridium aquilinum and the papilomatosis virus. We describe the clinical and laboratorial abnormalities observed during period of 6 months in naturally affect cows extensively raised in the north region of Paraná State. The animals had low concentrations of total calcium, with normal levels phosphorus and magnesium. Fractional excretion of calcium and phosphorus were increased. Metaplasia and hyperplasia in the epithelium as well as papilomas, hemangiomas, and transitional cell carcinomas were observed histopathologically in the urinary bladder. We were unable to demonstrate any viral presence by imunnohistochemistry and polymerase chain reaction (PCR of paraffin blocks.A hematúria enzoótica é uma doença crônica dos bovinos caracterizada clinicamente por hematúria intermitente que pode ser causada pela samambaia (Pteridium aquilinum e o vírus da papilomatose. Por meio deste estudo verificamos as alterações clínico-laboratoriais em bovinos, mestiços, fêmeas, naturalmente intoxicados pela samambaia, em propriedades rurais de criação extensiva na região norte do Paraná, durante o período de 6 meses. Os resultados mostraram baixo nível plasmático de cálcio, níveis plasmáticos normais para fósforo e magnésio, aumento da excreção urinária fracionada de cálcio e fósforo. Histopatologicamente foram observadas alterações neoplásicas como papiloma, hemangioma e carcinoma de células transicionais além de metaplasia e hiperplasia na bexiga. Provas de imuno-histoquimica e reação em cadeia pela polimerase (PCR de cortes parafinados mostraram resultado negativo para o agente viral.

  8. Taxonomic revision of the Palaeozoic marattialean fern Acithea Schimper

    Czech Academy of Sciences Publication Activity Database

    Zodrow, E. L.; Šimůnek, Z.; Cleal, Ch. J.; Bek, Jiří; Pšenička, J.

    2006-01-01

    Roč. 138, 3-4 (2006), s. 239-280 ISSN 0034-6667 R&D Projects: GA AV ČR IAA3013902 Institutional research plan: CEZ:AV0Z30130516 Keywords : Permo-Carboniferous * Acitheca * Marattiales * epiderms * in situ spores Subject RIV: EF - Botanics Impact factor: 1.170, year: 2006

  9. The colonisation of a former sea-floor by ferns

    NARCIS (Netherlands)

    Bremer, P.

    2007-01-01

    Het gaat goed met de varens in de Nederlandse bossen. Zeventig procent van de soorten neemt toe in aantal. De groei is voor een belangrijke deel te danken aan nieuwe leefgebieden in de bossen van Flevoland, waar zich binnen enkele decennia `hotspots` voor varens ontwikkelden. Dat is op wereldschaal

  10. Bracken fern (Pteridium aquilinum) poisoning in cattle in southern Brazil.

    Science.gov (United States)

    Gava, Aldo; da Silva Neves, Dalmo; Gava, Daniele; de Moura, Saliba Thiago; Schild, Ana Lucia; Riet-Correa, Franklin

    2002-12-01

    Epidemiological data on Pteridium aquilinum intoxication in cattle the state of Santa Catarina were obtained by review of diagnostic records from 1987 to 2001. Of 3,407 necropsied cattle, 244 (7.16%) were diagnosed as intoxicated by Paquilinum; 122 of those were of the hemorrhagic form, 103 had tumors in the upper digestive tract, 19 were cases of chronic hematuria. Annual losses due to this intoxication in this State are estimated at 10,657 cattle. The highest incidence of the hemorrhagic form occurs in 1-3-y-old cattle between March and July, and most cases of tumors of the upper digestive tract affect cattle older than Sy. The highest incidence of digestive tract tumors is at the base of the tongue and pharynx, and the lowest frequency is in the rumen and esophagus. The large economic losses caused PaQuilinum in Santa Catarina call for improved control measures for the disease.

  11. Development of microsatellite markers for the bracken fern, Pteridium aquilinum.

    Science.gov (United States)

    Chen, Xiaoqing; Wang, Jianxiu; Tian, Hongli; Zhang, Xianchun; Wen, Jun; Zhou, Shiliang

    2008-11-01

    We isolated eight novel polymorphic microsatellite loci from Pteridium aquilinum. These loci were characterized in 30 individuals, one from Bolivia, two from Peru, one from the USA, one from Japan, and 25 from Northeast China to Southwest China. The number of alleles per locus ranged from two to seven. The observed heterozygosity (H(O) ) ranged from 0.000 to 0.600 with an average of 0.3051, and the expected heterozygosity (H(E) ) ranged from 0.0966 to 0.7780 with an average of 0.4267. One locus deviated from Hardy-Weinberg equilibrium and four pairs of loci were found to be in linkage disequilibrium. These polymorphic loci will be useful in the study of the population genetic structure of Pteridium. © 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd.

  12. Konijnenburgia, a new genus of the fern family Matoniaceae

    Czech Academy of Sciences Publication Activity Database

    Kvaček, J.; Dašková, Jiřina

    2010-01-01

    Roč. 158, 3/4 (2010), s. 308-318 ISSN 0034-6667 R&D Projects: GA AV ČR IAA304070701 Institutional research plan: CEZ:AV0Z30130516 Keywords : Konijnenburgia * Nathorstia * Matoniaceae * palynology * spores Subject RIV: EF - Botanics Impact factor: 1.985, year: 2010

  13. First megafossil evidence of Cyatheaceous tree fern from the Indian ...

    Indian Academy of Sciences (India)

    sp. nov. CUH/PPL/IB7/TF/1. (a) Cyatheoid arrangeme- ment of vascular bundles within the leaf scar. Scale bar = 1 cm. (b) Stem surface showing the marks of root traces within root (marked by red arrow). Scale bar = 0.5 cm. 3. Systematic description. Order: Cyatheales. Family: Cyatheaceae Kaulfuss. Genus: Cyathea Smith.

  14. Dryopsis (Dryopteridaceae, A Fern Genus New to Vietnam

    Directory of Open Access Journals (Sweden)

    Hui-Hui Ding

    2013-03-01

    Full Text Available Dryopsis clarkei (Baker Holttum & P.J. Edwards, representing the whole genus, is reported new to Vietnam. A detailed description, including the variation of gross morphology, spore morphology, and chromosome counts, is provided by means of words as well as photographs or drawings. Dryopsis clarkei is for the first time demonstrated to be a sexual diploid (2n = 82, with rather stable morphology except for the length of stipe.

  15. Diaspididae (Hemiptera, Coccoidea in sori of two fern species

    Directory of Open Access Journals (Sweden)

    Marcelo Santos

    2015-12-01

    Duas Espécies de Cochonilhas (Hemiptera: Diaspididae Associadas com Soros de Samambaias Resumo. A presente comunicação relata a presença de duas espécies de cochonilhas Hemiberlesia palmae (Cockerell e Pinnaspis strachani (Cooley (Coccoidea, Diaspididae, associadas respectivamente com Asplenium serratum L. (Aspleniaceae e Niphidium crassifolium (L. Lellinger (Polypodiaceae. É o primeiro registro de uma samambaia como planta hospedeira de Hemiberlesia palmae.  Nas duas espécies de samambaias, os diaspidídeos encontravam-se concentrados principalmente ao redor dos soros.

  16. Solar energy system economic evaluation: Fern Tunkhannock, Tunkhannock, Pennsylvania

    Science.gov (United States)

    1980-01-01

    The economic performance of an Operational Test Site (OTS) is described. The long term economic performance of the system at its installation site and extrapolation to four additional selected locations to demonstrate the viability of the design over a broad range of environmental and economic conditions is reported. Topics discussed are: system description, study approach, economic analysis and system optimization, and technical and economical results of analysis. Data for the economic analysis are generated through evaluation of the OTS. The simulation is based on the technical results of the seasonal report simulation. In addition localized and standard economic parameters are used for economic analysis.

  17. The fern herbarium at the Komarov Botanical Institute, Leningrad

    NARCIS (Netherlands)

    Holttum, R.E.

    1977-01-01

    The Herbarium is arranged according to Christensen’s Index Filicum (1905). I examined all the Old World specimens in Dryopteris and Aspidium, both in the general herbarium and in the separate herbarium for China and Japan. It appears that the genera segregated by Christensen from Dryopteris (e.g.

  18. A new late Westphalian fossil marattialean fern from Nova Scotia

    Czech Academy of Sciences Publication Activity Database

    Pšenička, J.; Bek, Jiří; Zodrow, E.; Cleal, J. CH.; Hemsley, A. R.

    2003-01-01

    Roč. 142, č. 2 (2003), s. 199-212 ISSN 0024-4074 Institutional research plan: CEZ:AV0Z3013912 Keywords : Pennsylvanian * sporangia * spores Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.871, year: 2003

  19. First megafossil evidence of Cyatheaceous tree fern from the Indian ...

    Indian Academy of Sciences (India)

    Subir Bera1 Sudha Gupta2 Mahasin Ali Khan1 Aniruddha De1 Radhanath Mukhopadhyay3. Centre of Advanced Study, Department of Botany, University of Calcutta, 35, B.C. Road, Kolkata 700 019, West Bengal, India. Department of Botany, University of Kalayni, Nadia 741 235, West Bengal, India. Department of Botany ...

  20. El juego de baloncesto modificado como un medio recreativo para los jóvenes entre 17 y 23 años sexo masculino de la zona 24 de la circunscripción Ceferino Fernández del municipio pinar del Río

    Directory of Open Access Journals (Sweden)

    Marilin Páez Basabe

    2009-06-01

    Full Text Available En los marcos específicos de la participación comunitaria esta se activa y se desarrolla en nexo con los objetivos de la política social estratégicamente diseñadas, nuestro país las investigaciones sobre las recreación física participativa surgen como una necesidad indispensable a consecuencia del proceso de desarrollo económico socia lo que ha  alcanzadas en últimos años la consolidación de la revolución cubana. La presente tesis tiene sus raíces en las contradicciones existentes entre lo ideal un disfrute pleno recreativo de los jóvenes a partir de su preferencias cubriendo en Gan medida sus necesidades , lo real la existencia de esas motivaciones  que  permitan  la  recreación física  placentera  acorde  a  los principios de la sociedad que permita elevar la calidad de vida de una forma sana  placentera  nos  proponemos  para  darle  tratamiento  al  problema presentado la utilización del juego de baloncesto como medio recreativo para los  jóvenes  entre  17  y  23  años  .Objetivos  general:  Diseñar  las  variantes manipulativas  a utilizar en  el juego de baloncesto modificado como un medio recreativo  para los jóvenes entre 17 y 23 años de edad del  sexo masculino de la zona 24 del circunscripción Ceferino Fernández  del municipio pinar del Rió Aportes  teóricos : Contribución a la  teoría: se definen los conceptos fundamentales que da origen ala investigación juego de baloncesto modificado como un medio recreativo y este lleva implicitotas definiciones a seguir en las variables  manipulativas  aporte  practico:  La  recreación  física   a  través  del deporte simplificado para la comunidad Novedad científica: La creación de una instalación de baloncesto rústica para el juego modificado dentro  de  la  comunidad  propiciando  a  diario  un  espectáculo  deportivo recreativo para todos en la actualidad. El rescate del deporte como medio de

  1. Ciclo anual de la clorofila-α satelital en el archipiélago de Juan Fernández (33°S, Chile Annual cycle of the satellite chlorophyll-a in the Juan Fernandez archipelago (33°S, Chile

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2012-09-01

    Full Text Available La variabilidad espacial y temporal del ciclo anual de la clorofila-α en el archipiélago de Juan Fernández se analiza usando ocho anos de datos satelitales de clorofila-α, viento, corrientes y nivel del mar. Este archipiélago está conformado por tres islas: Robinson Crusoe-Santa Clara (RC-SC y Alejandro Selkirk (AS. Las islas RC-SC se encuentran en una región de alta energía cinética y mayores concentraciones de clorofila-α definida como Zona de Transición Costera, en cambio la isla AS se encuentra en una región de baja energía cinética y menores concentraciones de clorofila-α denominada Zona Oceánica. RC-SC posee un incremento de las concentraciones de clorofila-a en el lado suroeste, mientras que AS posee sus mayores concentraciones en el lado oeste, indicando la presencia de procesos forzantes diferentes. En ambas islas el ciclo anual de la clorofila es significativo y comienza a incrementar en abril, alcanzando valores relativamente altos entre junio y noviembre, disminuyendo hacia diciembre, hasta alcanzar un mínimo hacia fines de marzo. Este ciclo anual aparece desacoplado con el viento y acoplado con la energía cinética. Incrementos invernales de clorofila-a aparecen vinculados con remolinos de mesoescala provenientes de la zona continental, mientras que incrementos primaverales se podrían asociar a procesos locales vinculados al "efecto masa de isla". En ambas islas existen incrementos significativos de la clorofila-a en la banda anual y cuasi-bianual, pero sólo en AS se encontró una fluctuación significativa en la banda interanual vinculada con el Nino y la Oscilación del Sur.The spatial and temporal variability of the annual cycle of chlorophyll-a in the Juan Fernandez archipelago is analyzed through eight years of satellite data of chlorophyll-a, wind, currents and sea level. This archipelago consists of three islands: Robinson Crusoe-Santa Clara (RC-SC and Alexander Selkirk (AS. The RC-SC islands are in a

  2. Diversity and distribution patterns of ferns and lycophytes in a cloud forest in Mexico

    Directory of Open Access Journals (Sweden)

    Arturo Sánchez-González

    2016-01-01

    Full Text Available La relación de la riqueza, diversidad y distribución de especies de helechos y licopodios con algunas variables climáticas y edáficas se analizó en el bosque mesófilo de montaña del municipio de Tlanchinol, Hidalgo. Se establecieron 24 parcelas de muestreo de 400 m 2 cada una, en tres pisos altitudinales situados entre 1,107 y 1,903 m. La diversidad alfa y beta, y el valor de importancia relativa (VIR de las especies se estimaron en cada parcela. La relación entre la riqueza, diversidad, VIR y las variables ambientales se estableció mediante análisis de redundancia, regresión lineal y árboles de regresión. Pocas especies presentaron VIR altos por parcela; los valores de riqueza y diversidad no mostraron diferencias estadísticamente significativas ( P < 0.05 con respecto a la altitud, pero s í con la temperatura mínima del mes más frío, precipitación del trimestre más cálido, orientación y pendiente. La diversidad beta incrementó con la altitud; esta diversidad fue baja entre pisos cercanos y alta en los extremos del gradiente. La distribución de las especies se relacion ó positivamente con la materia orgánica, isotermalidad y contenido de sodio; y negativamente con la precipitación del mes más seco, evapotranspiración real anual y evapotranspiración real en la temporada de lluvias.

  3. Gene Flow among Populations of Two Rare Co-Occurring Fern Species Differing in Ploidy Level

    Czech Academy of Sciences Publication Activity Database

    Bucharová, Anna; Münzbergová, Zuzana

    2012-01-01

    Roč. 7, č. 9 (2012), e45855 E-ISSN 1932-6203 R&D Projects: GA MŠk 2B06178; GA ČR GA526/09/0549 Institutional support: RVO:67985939 Keywords : genetic variation * tetraploid species * diploid species Subject RIV: EF - Botanics Impact factor: 3.730, year: 2012

  4. Ferns and flowering plants of Klaserie Private Nature Reserve, eastern Transvaal: an annotated checklist

    Directory of Open Access Journals (Sweden)

    N. Zambatis

    1994-10-01

    Full Text Available An annotated checklist of the plant taxa of the Klaserie Private Nature Reserve, eastern Transvaal Lowveld, is presented. Of the 618 infrageneric taxa recorded, six are pteridophytes and the remainder angiosperms. Of these, 161 are monocotyledons and 451 dicotyledons. Five of the latter are currently listed in the Red Data List of the Transvaal, two of which are first records for the Transvaal Lowveld. The vegetation of the reserve shows strong affinities with the Savanna Biome, and to a lesser degree, with the Grassland Biome.

  5. Adaptation of a widespread epiphytic fern to simulated climate change conditions

    NARCIS (Netherlands)

    Hsu, R.C.C.; Oostermeijer, J.G.B.; Wolf, J.H.D.

    2014-01-01

    The response of species to climate change is generally studied using ex situ manipulation of microclimate or by modeling species range shifts under simulated climate scenarios. In contrast, a reciprocal transplant experiment was used to investigate the in situ adaptive response of the elevationally

  6. Fern- und Fehlzündungen. Bedenken zu Ingeborg Bachmanns Wittgenstein-Rezeption / Georg Gimpl

    Index Scriptorium Estoniae

    Gimpl, Georg, 1949-

    2007-01-01

    Ettekanne Ingeborg Bachmanni 80. sünniaastapäevaks pühendatud rahvusvaheliselt konverentsilt Tartus 12.-13. aprillil 2006. aastal. Wittgensteini retseptsioonist Bachmanni loomingust Ludwig Wittgensteini "Loogilis-filosoofilise traktaadi" põhjal (Tartu : Ilmamaa, 1996)

  7. A re-definition of the fern-genus Taenitis Willd

    NARCIS (Netherlands)

    Holttum, R.E.

    1968-01-01

    The present paper includes a new definition of the genus Taenitis, the addition of five species to it (one of them new), a key to the known species, a description of each with citation of synonyms and of the more important previous literature. The genus was established for the very widely

  8. Population Study of the Golden Chicken Fern (Cibotium barometz (L. J. Sm. in Riau Province, Sumatra

    Directory of Open Access Journals (Sweden)

    Titien Ngatinem Praptosuwiryo

    2017-05-01

    Full Text Available Cibotium barometz (L. J.Sm. (Cibotiaceae is an important export commodity for both traditional and mod-ern medicine. Populations of this species in several countries have decreased rapidly due to the uncontrolled collection of the rhizome parts for medicinal purposes. Since 1976, this species has been included in Appendix II of the Convention on International Trade in Endangered Species (CITES. This means that no export is allowed without a prior permit issued by the CITES committee.  In order to utilize an endangered species sustainably, the global NDF (Non-Detriments Finding system is applied for determining annual quotas. Therefore, monitoring and updating the inventory of C. barometz in its natural habitat should be carried out annually. A population study of C. barometz carried out in 2011 in Riau Province, Sumatra, is reported here. The aims of the study were: 1 to inventory C. barometz and determine its variation in Riau Province, Suma-tra, 2 to study the distribution and ecology of C. barometz, and 3 to assess the population size of this spe-cies by using random search methodology incorporating belt line transects. Two variants of C. barometz are recognized; they are the golden yellow and golden brown variants. C. barometz is distributed in eight loca-tions of Kampar District of Riau Province, in the secondary forest and rubber agroforest between 80 m and 600 m above sea level (asl. This species grows well in open to partially opened areas of secondary forest and rubber plantation in hills with a range of slope between 30° and 90°, with a relatively high humidity, 60 – 90%, in acid to nearly neutral soil, with a range of soil fertility from very poor to very humus rich soil.  The average population density determined in our study was 20 plants per 100 square meter. The highest popula-tion size was in the secondary forest of Bukit Kuda Beban at 590 – 600 m asl., viz. 9405 plants with a popula-tion density  of 47 plants per 100 square meter.

  9. The Tree-Ferns of the genus Cyathea in Australasia and the Pacific

    NARCIS (Netherlands)

    Hollttum, R.E.

    1964-01-01

    The present account of this genus follows the lines of that adopted for Flora Malesiana (ser. 11, 1, part 2, 1963). While studying Malesian species, I examined the types of those in neighbouring regions, to discover to what extent Malesian species were distributed further to the East and South-east.

  10. Functional groups of fossil marattialeans: chemotaxonomic implications for Pennsylvanian tree ferns and pteridophylls

    Czech Academy of Sciences Publication Activity Database

    Pšenička, J.; Zodrow, E. L.; Mastalerz, M.; Bek, Jiří

    2005-01-01

    Roč. 61, 3-4 (2005), s. 259-280 ISSN 0166-5162 R&D Projects: GA AV ČR(CZ) IAA3013902 Institutional research plan: CEZ:AV0Z30130516 Keywords : interdisciplinary approach * functional groups * FTIR Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.397, year: 2005

  11. Effects of arsenic on nitrate metabolism in arsenic hyperaccumulating and non-hyperaccumulating ferns

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Nandita [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India); Ma, Lena Q., E-mail: lqma@ufl.ed [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Vu, Joseph C. [Chemistry Research Unit, CMAVE, USDA-ARS, Gainesville, FL 32608-1069 and Agronomy Department, University of Florida, Gainesville, FL 32611-0500 (United States); Raj, Anshita [Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India)

    2009-08-15

    This study investigated the effects of arsenic on the in vitro activities of the enzymes (nitrate reductase and nitrite reductase) involved in nitrate metabolism in the roots, rhizomes, and fronds of four-month old Pteris vittata (arsenic - hyperaccumulator) and Pteris ensiformis (non-arsenic--hyperaccumulator) plants. The arsenic treatments (0, 150, and 300 muM as sodium arsenate) in hydroponics had adverse effects on the root and frond dry weights, and this effect was more evident in P. ensiformis than in P. vittata. Nitrate reductase and nitrite reductase activities of arsenate-treated plants were reduced more in P. ensiformis than in P. vittata. This effect was accompanied by similar decreases in tissue NO{sub 3}{sup -} concentrations. Therefore, this decrease is interpreted as being indirect, i.e., the consequence of the reduced NO{sub 3}{sup -} uptake and translocation in the plants. The study shows the difference in the tolerance level of the two Pteris species with varying sensitivity to arsenic. - Arsenic reduced the activity of nitrate and nitrite reductase more in Pteris ensiformis than Pteris vittata.

  12. New data on stands of fern Athyrium distentifolium /Opiz/ in the Beskydy Mts

    Czech Academy of Sciences Publication Activity Database

    Tůma, Ivan; Holub, Petr; Fiala, Karel

    2008-01-01

    Roč. 1, č. 1 (2008), s. 89-94 ISSN 1803-2451 R&D Projects: GA AV ČR(CZ) IAA600050616 Institutional research plan: CEZ:AV0Z60050516 Keywords : decomposition * N fertilization * population structure Subject RIV: EF - Botanics

  13. Ptaquiloside in Irish Bracken Ferns and Receiving Waters, with Implications for Land Managers

    Directory of Open Access Journals (Sweden)

    Connie O’Driscoll

    2016-04-01

    Full Text Available Ptaquiloside, along with other natural phytotoxins, is receiving increased attention from scientists and land use managers. There is an urgent need to increase empirical evidence to understand the scale of phytotoxin mobilisation and potential to enter into the environment. In this study the risk of ptaquiloside to drinking water was assessed by quantifying ptaquiloside in the receiving waters at three drinking water abstraction sites across Ireland and in bracken fronds surrounding the abstraction sites. We also investigated the impact of different management regimes (spraying, cutting and rolling on ptaquiloside concentrations at plot-scale in six locations in Northern Ireland, UK. Ptaquiloside concentrations were determined using recent advances in the use of LC-MS for the detection and quantification of ptaquiloside. The results indicate that ptaquiloside is present in bracken stands surrounding drinking water abstractions in Ireland, and ptaquiloside concentrations were also observed in the receiving waters. Furthermore, spraying was found to be the most effective bracken management regime observed in terms of reducing ptaquiloside load. Increased awareness is vital on the implications of managing land with extensive bracken stands.

  14. Flores, Fernández y Oliva: tres azulejeros para las obras reales de Felipe II

    Directory of Open Access Journals (Sweden)

    Pleguezuelo, Alfonso

    2002-06-01

    Full Text Available Que las obras de arquitectura promocionadas por Felipe II eran acabadas frecuentemente con revestimientos de azulejos es una idea conocida desde hace tiempo. El ejemplo más frecuentemente aducido es el de los aposentos del mismo rey en el Monasterio de San Lorenzo de El Escorial aunque podrían ser citados muchos más casos conservados y otros conocidos a través de la documentación. Este rasgo de la arquitectura filipina y el personal interés del rey por el asunto debió ser un importante acicate para el desarrollo de la azulejería española en la segunda mitad del siglo XVI. Tres artistas han sido citados desde hace años como autores de los azulejos para Felipe II. Por un lado, el flamenco Juan Flores, del que tan sólo se tenían unas pocas noticias literarias sobre su vida y su obra y que recientemente he tenido la oportunidad de revisar a luz de nuevos documentos y obras.…

  15. Nuclear bodies in the maturing egg cell of a fern, Pteridium aquilinum.

    Science.gov (United States)

    Bell, P R

    1983-03-01

    Nuclear bodies about 250 nm in diameter, and with a strong affinity for uranium and acriflavine, appear in the nuclei of maturing egg cells of Pteridium. Many enter well-defined evaginations of the nucleus. The nuclear bodies are almost wholly digested by Pronase, but are resistant to ribonuclease and deoxyribonuclease. Radioactive labelling gives no evidence of the presence of nucleic acids, but X-ray microprobe analysis indicates phosphorus. It is concluded that the bodies consist entirely of acidic protein, possibly phosphorylated. This protein may be a structural component of the nucleus, temporarily displaced and aggregated as a consequence of the fine dispersal of the chromatin.

  16. Genotoxic activity and inhibition of soil respiration by ptaquiloside, a bracken fern carcinogen

    DEFF Research Database (Denmark)

    Schmidt, Bjørn; Rasmussen, L.H.; Svendsen, Gitte Winkel

    2005-01-01

    Ptaquiloside (PTA) is a natural toxin produced by bracken (Pteridium aquilinum [L.] Kuhn). Assessment of PTA toxicity is needed because PTA deposited from bracken to soil may leach to surface and groundwater. Inhibition of soil respiration and genotoxic activity of PTA was determined by a soil...

  17. Pteridium aquilinum (bracken fern) toxicity in cattle in the humid Chaco of Tarija, Bolivia.

    Science.gov (United States)

    Marrero, E; Bulnes, C; Sánchez, L M; Palenzuela, I; Stuart, R; Jacobs, F; Romero, J

    2001-06-01

    We studied the toxicity caused by chronic ingestion of Pteridium aquilinum (bracken) in cattle in the humid Chaco of Tarija, Bolivia. Bovine enzootic haematuria (BEH) and Carcinoma of the esophagus (CE) affected the herds. Sick animals showed caquexia, anemia, leucopenia and urine that turned from pink to intense red color with the presence of blood clots. Cattle grazed in the humid forests of the mountains where P aquilinum represented more than 50% of the plants. P aquilinum var arachnoideum and P aquilinum var Caudatum were present. Toxic norsesquiterpene, ptaquiloside, was identified in both varieties. Carcinomas were in the urinary bladders and esophagus of 100% and 50% of the cattle, respectively. Control of the intoxication could be difficult due to geographic characteristics of this Bolivian region.

  18. Cryptic species in the fern Ceratopteris thalictroides (Parkeriaceae). III. Referential diagnostic characters of three cryptic species.

    Science.gov (United States)

    Masuyama, Shigeo

    2008-05-01

    Three cryptic species of Ceratopteris thalictroides, named the south type, the north type and the third type, were examined for their morphological characteristics, using sporophytes cultivated under common conditions. The discriminant analysis for leaf characters followed by one-way layout ANOVA or Kruskal-Wallis test for selected combinations of characters revealed that the following characters may be effective for identifying the three types: the relative lengths of stipe to blade and to pinna, the degree of dissection, the segment densities on rachis and pinna rachis, and the elongation degree of ultimate segments. The number of annulus cells on sporangia also proved to be a possible distinguishing character. As morphological data were obtained from a limited number of cultivated sporophytes, they are regarded as not definitive, but only referential diagnostic characters of the types and should be utilized not solely, but collectively, to avoid identification errors of the types. An identification trial using herbarium specimens proved these diagnostic characters to be useful to a considerable degree.

  19. Fern spore longevity in saline water: can sea bottom sediments maintain a viable spore bank?

    NARCIS (Netherlands)

    Groot, de G.A.; During, H.

    2013-01-01

    Freshwater and marine sediments often harbor reservoirs of plant diaspores, from which germination and establishment may occur whenever the sediment falls dry. Therewith, they form valuable records of historical interand intraspecific diversity, and are increasingly exploited to facilitate diversity

  20. Divergent immunomodulatory effects of extracts and phenolic compounds from the fern Osmunda japonica Thunb

    Czech Academy of Sciences Publication Activity Database

    Zhu, X.; Li, Y. J.; Yang, L.; Zhang, D.; Chen, Y.; Kmoníčková, Eva; Weng, X. G.; Yang, Q.; Zídek, Zdeněk

    2013-01-01

    Roč. 19, č. 10 (2013), s. 761-770 ISSN 1672-0415 R&D Projects: GA MŠk(CZ) ME10116 Institutional support: RVO:68378041 Keywords : phenolics * immunomodulation * Osmunda japonica Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.401, year: 2013

  1. Measuring air layer volumes retained by submerged floating-ferns Salvinia and biomimetic superhydrophobic surfaces

    Directory of Open Access Journals (Sweden)

    Matthias J. Mayser

    2014-06-01

    Full Text Available Some plants and animals feature superhydrophobic surfaces capable of retaining a layer of air when submerged under water. Long-term air retaining surfaces (Salvinia-effect are of high interest for biomimetic applications like drag reduction in ship coatings of up to 30%. Here we present a novel method for measuring air volumes and air loss under water. We recorded the buoyancy force of the air layer on leaf surfaces of four different Salvinia species and on one biomimetic surface using a highly sensitive custom made strain gauge force transducer setup. The volume of air held by a surface was quantified by comparing the buoyancy force of the specimen with and then without an air layer. Air volumes retained by the Salvinia-surfaces ranged between 0.15 and 1 L/m2 depending on differences in surface architecture. We verified the precision of the method by comparing the measured air volumes with theoretical volume calculations and could find a good agreement between both values. In this context we present techniques to calculate air volumes on surfaces with complex microstructures. The introduced method also allows to measure decrease or increase of air layers with high accuracy in real-time to understand dynamic processes.

  2. Chalcone derivatives from the fern Cyclosorus parasiticus and their anti-proliferative activity.

    Science.gov (United States)

    Wei, Han; Zhang, Xuenong; Wu, Guanghua; Yang, Xian; Pan, Songwei; Wang, Yanyan; Ruan, Jinlan

    2013-10-01

    Three new chalcone derivatives, named parasiticins A-C (1-3), were isolated from the leaves of Cyclosorus parasiticus, together with four known chalcones, 5,7-dihydroxy-4-phenyl-8-(3-phenyl-trans-acryloyl)-3,4-dihydro-1-benzopyran-2-one (4), 2'-hydroxy-4',6'-dimethoxychalcone (5), 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (6), 2',4'-dihydroxy-6'-methoxy-3'-methylchalcone (7). The chemical structures of the new isolated compounds were elucidated unambiguously by spectroscopic data analysis. The cytotoxic activities of compounds 1-7 were evaluated against six human cancer cell lines in vitro. Compounds 3 and 6 exhibited substantial cytotoxicity against all six cell lines, especially toward HepG2 with the IC₅₀ values of 1.60 and 2.82 μM, respectively. Furthermore, we demonstrated that compounds 3 and 6 could induce apoptosis in the HepG2 cell line, which may contribute significantly to their cytotoxicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Evidence for radiations of cheilanthoid ferns in the Greater Cape Floristic Region

    DEFF Research Database (Denmark)

    Eiserhardt, Wolf L.; Rohwer, Jens G.; Russell, Stephen J.

    2011-01-01

    appears to stem primarily from in situ diversification, not from immigration. This pattern resembles the numerous radiations of angiosperm clades in the GCFR, and may be caused by the same factors. We did not find evidence for rapid, synchronised radiations as documented for some, albeit not all...

  4. Ptaquiloside in irish bracken ferns and receiving waters, with implications for land managers

    DEFF Research Database (Denmark)

    O'Driscoll, Connie; Ramwell, Carmel; Harhen, Brendan

    2016-01-01

    Ptaquiloside, along with other natural phytotoxins, is receiving increased attention from scientists and land use managers. There is an urgent need to increase empirical evidence to understand the scale of phytotoxin mobilisation and potential to enter into the environment. In this study the risk...

  5. Dissipation of pterosin B in acid soils - tracking the fate of the bracken fern carcinogen ptaquiloside

    DEFF Research Database (Denmark)

    Skourti-Stathaki, Eirini; Clauson-Kaas, Frederik; Brandt, Kristian Koefoed

    2016-01-01

    -free areas. Soil samples were incubated with pterosin B at 3 and 8 μg g(-1) for 10 days, whereas sterile (autoclaved) samples were incubated for 23 days. Pterosin B showed unexpected fast degradation in soils with full degradation in topsoils in 2-5 days. Pterosin B dissipation followed the sum of two...

  6. Purification and Characterization of a Novel (R)-Mandelonitrile Lyase from the Fern Phlebodium aureum.

    Science.gov (United States)

    Wajant, H.; Forster, S.; Selmar, D.; Effenberger, F.; Pfizenmaier, K.

    1995-12-01

    Using high-performance liquid chromatography and nuclear magnetic resonance we identified vicianin as the cyanogenic compound of Phlebodium aureum. The (R)-hydroxynitrile lyase involved during cyanogenesis in the catabolism of the aglycon ([R]-mandelonitrile) was purified to apparent homogeneity. The purified holoenzyme is a homomultimer with subunits of Mr = 20,000. At least three isoforms of the enzyme exist. In contrast to other hydroxynitrile lyases, mandelonitrile lyase (MDL) from P. aureum was not inhibited by sulfhydryl- or hydroxyl-modifying reagents, suggesting a different catalytic mechanism. The enzyme is active over a broad temperature range, with maximum activity between 35 and 50[deg]C, and a pH optimum at 6.5. In contrast to (R)-MDLs isolated from several species of the Rosaceae family, (R)-MDL from P. aureum is not a flavoprotein. The substrate specificity was investigated using immobilized enzyme and diisopropyl ether as solvent. The addition of cyanide to aromatic and heterocyclic carbonyls is catalyzed by this (R)-MDL, whereas aliphatic carbonyls are poorly converted.

  7. 75 FR 23151 - Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper

    Science.gov (United States)

    2010-05-03

    ... the importation and interstate movement of those plants that are designated as noxious weeds in Sec. 360.200. The PPA defines ``noxious weed'' as ``any plant or plant product that can directly or... Imports, Plants (Agriculture), Quarantine, Reporting and recordkeeping requirements, Transportation, Weeds...

  8. Two cyclohexenone glycosides from the North American fern Woodwardia virginica (L.) Smith

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Dembitsky, V. M.; Hanuš, L. O.

    2003-01-01

    Roč. 63, - (2003), s. 931-937 ISSN 0031-9422 Institutional research plan: CEZ:AV0Z5020903 Keywords : wiidwardia virginica * blechnaceae Subject RIV: EE - Microbiology, Virology Impact factor: 1.889, year: 2003

  9. In situ spores from Pennsylvanian ferns from Upper Silesian basin (Czech Republic, Poland)

    Czech Academy of Sciences Publication Activity Database

    Pšenička, J.; Bek, Jiří

    2008-01-01

    Roč. 2008, č. 2 (2008), s. 228-228 ISSN 0946-8978. [International Palynological Congress /12./ ; International Organisation of Palaeobotany Conference /8./. 30.08.2008-05.09.2008, Bonn] R&D Projects: GA AV ČR IAA300130503 Institutional research plan: CEZ:AV0Z30130516 Keywords : spores * Upper Silesian Basin Subject RIV: DB - Geology ; Mineralogy

  10. Evolution of the western segment of Juan Fernández Ridge (Nazca Plate): plume vs. plate tectonic processes

    Science.gov (United States)

    Lara, Luis E.; Rodrigo, Cristián; Reyes, Javier; Orozco, Gabriel

    2014-05-01

    The Juan Fernandez Ridge (Eastern Pacific, Nazca Plate) is thought to be a classic hot spot trail because of the apparent age progression observed in 40Ar-39Ar data. However, geological evidence and some thermochronological data suggest a more complex pattern with a rejuvenation stage in Robinson Crusoe Island, the most eroded of the Juan Fernandez Archipelago. In fact, a postshield stage at 900-700 ka separates the underlying shield-related pile from the post-erosional alkaline succession (Ba/Yb=38.15; La/Yb=15.66; Ba/Y=20.27; Ba/Zr=2.31). Shield volcanoes grew at high effusion rate at ca. 5-4 Ma erupting mostly tholeiitic to transitional magmas (Ba/Yb=18.07-8.32; La/Yb=4.59-9.84; Ba/Y=4.24-8.18; Ba/Zr=0.73-1.09). Taken together, shield volcanoes form a continuous plateau with a base at ca. 3900 mbsl. However, a more complex structural pattern can be inferred from geophysical data, which suggest some intracrustal magma storage and a more extended area of magma ascent. A role for the Challenger Fracture Zone is hypothesized fueling the controversy between pristine plume origin and the effect of plate tectonic processes in the origin of intraplate volcanism. This research is supported by FONDECYT Project 1110966.

  11. Variation in the mitochondrial control region in the Juan Fernández fur seal (Arctocephalus philippii).

    Science.gov (United States)

    Goldsworthy, S; Francis, J; Boness, D; Fleischer, R

    2000-01-01

    The Juan Fernandez fur seal (Arctocephalus philippii was allegedly extremely abundant, numbering as many as 4 million prior to sealing which continued from the late 17th to the late 19th century. By the end of the sealing era the species was thought to be extinct until they were rediscovered at Alejandro Selkirk Island in 1965. Historic records would suggest that the species underwent a substantial population bottleneck as a result of commercial sealing, and from population genetic theory we predicted that the genetic variability in the species would be low. We compared the mtDNA control region sequence from 28 Juan Fernandez fur seals from two islands in the Juan Fernandez Archipelago (Chile). Contrary to expectation, we found that variation in the Juan Fernandez fur seals is not greatly reduced in comparison to other pinniped taxa, especially given the apparent severity of the bottleneck they underwent. We also determined minor, but significantly different haplotype frequencies among the populations on the two islands (Alejandro Selkirk and Robinson Crusoe Islands), but no difference in their levels of variability. Such differences may have arisen stochastically via a recent founder event from Alejandro Selkirk to Robinson Crusoe Island or subsequent genetic drift.

  12. New Species of the Fern Genus Lindsaea (Lindsaeaceae) from New Guinea with Notes on the Phylogeny of L. sect. Synaphlebium.

    Science.gov (United States)

    Dong, Shi-Yong; Zuo, Zheng-Yu; Chao, Yi-Shan; Damas, Kipiro; Sule, Bernard

    2016-01-01

    To determine the taxonomic identities and the systematic positions of some collections of Lindsaea sect. Synaphlebium (Lindsaeaceae) from Papua New Guinea, we conducted morphological comparisons and phylogenetic analyses on the whole section. A total of 22 morphological characters were selected and coded for each of all known taxa in L. sect. Synaphlebium, and were analyzed using maximum parsimony. The datasets containing either of or combined two plastid DNA sequences (trnL-trnF spacer and trnH-psbA spacer) of 37 taxa were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. Morphological comparisons revealed two new species which are formally published here as L. subobscura and L. novoguineensis. Lindsaea subobscura is similar to sympatric L. obscura and L. modesta but differs in the obviously reduced upper pinnules and other characters. Lindsaea novoguineensis is most similar to L. pacifica from Melanesia but differs in having rhomboid pinnules with truncate apices and concave soral receptacles. Molecular analyses resolved L. sect. Synaphlebium and allied species into five well-supported clades, namely L. rigida clade, L. obtusa clade, L. pulchella clade, L. multisora clade, and L. cultrata clade. The new species L. novoguineensis is included in L. obtusa clade; L. subobscura is in L. pulchella clade; whereas the majority of L. sect. Synaphlebium is clustered in L. cultrata clade. As the section Synaphlebium sensu Kramer is strongly suggested as polyphyletic, we propose the concept of a monophyletic L. sect. Synaphlebium in a broad sense that comprises five lineages. The morphological circumscription of L. sect. Synaphlebium sensu lato and the divergence in morphology, habit, and distribution between the five lineages are briefly discussed. Further molecular study is needed to test the systematic positions of 16 other species which are supposed to be within L. sect. Synaphlebium sensu lato but have not been included in this and previous molecular analyses.

  13. Direkte Kontakte zu Deutschland aus und in der Ferne (Direct Contact with Germany from and at a Distance).

    Science.gov (United States)

    Wicke, Rainer E.

    This guide is a summary of ideas for enhancing the teaching of German through direct contact with Germany or German people without traveling abroad. The following ideas are highlighted: (1) correspondence (pen pals) with students in Germany; (2) audiotape recordings as an alternative to letter writing; (3) the exchange of videotape recordings with…

  14. Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forest in Nepal

    Czech Academy of Sciences Publication Activity Database

    Adhikari, Y. P.; Fischer, A.; Fischer, H. S.; Rokaya, Maan Bahadur; Bhattarai, P.; Gruppe, A.

    2017-01-01

    Roč. 14, č. 6 (2017), s. 1065-1075 ISSN 1672-6316 Grant - others:European Comission(XE) 212459 Program:FP7 Institutional support: RVO:67985939 Keywords : environmental factors * epiphytes * large trees * indicator species * multivariate and univariate analyses * permutations tests Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 1.016, year: 2016

  15. Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forests in Nepal

    Czech Academy of Sciences Publication Activity Database

    Adhikari, Y. P.; Fischer, A.; Fischer, H. S.; Rokaya, Maan Bahadur; Bhattarai, P.; Gruppe, A.

    2017-01-01

    Roč. 14, č. 6 (2017), s. 1065-1075 ISSN 1672-6316 R&D Projects: GA ČR GB14-36098G Institutional support: RVO:86652079 Keywords : vascular epiphytes * kathmandu valley * managed forests * dry forest * land-use * richness * conservation * biodiversity * assemblages * preferences * Environmental factors * Epiphytes * Large trees * Indicator species * Multivariate and univariate analyses * Permutations tests Subject RIV: EF - Botanics OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 1.016, year: 2016

  16. Structure and Development of the Gametophytes of Philippine Cheilanthoid Ferns, III. Cheilanthes concolor (Langsdorff et Fischer R. Tryon

    Directory of Open Access Journals (Sweden)

    Prescillano Zamora

    1993-12-01

    Full Text Available The gametophytes of Cheilanthes concolor (Langsdorff et Fischer R. Tryon from the Philippines (Quezon City are no different in pattern of development and in morphology from those from India with one possible notable difference, which is, that the gametophytes under report (which were grown from spores produced from 32-sporate sporangia are apogamous while those from India (sporangial type of source was not stated are sexual.

  17. Procedimientos constructivos en el "Museo de la Novela de la Eterna", de Macedonio Fernández

    Directory of Open Access Journals (Sweden)

    Fabiola Orquera

    2016-04-01

    Full Text Available La idea de este trabajo es que el rechazo a la poética realista, premisa que funda Museo de la Novela de la Eterna, rige su escritura a nivel de su enunciación y su enunciado, de las instancias del autor y del lector y del espacio que ocupa en el corpus literario. Para comprobar tal afirmación se considerarán los principios constructivos de este texto, impregnados de la estética surrealista, pero novedosos en cuanto se expresan en prosa narrativa. A partir de ellos se intentará identificar los recursos alternativos que organizan la escritura, inspirados en el deseo de mostrar el trabajo productivo de toda "obra" literaria, mediante la deconstrucción (en el sentido literal de lo verosímil. En base a estas consideraciones, se establecerán relaciones entre la novela y líneas teóricas (literarias actuales. The idea of this work is that the rejection of realistic poetic, which is the premise of Museo de la Novela de la Eterna, guides its writing at the level of the narrative voice and the narration, of the author's and reader's degrees and of its place in literature. The text's constructive principles are studied, which are steeped in the surrealistic aesthetic, but they are new since they are expressed in narrative prose. The alternative resources that organize the writing are identified, inspired by the desire to show the "productive work" of all literary "work", through the deconstruction (in the literal sense of the probable. Based on these considerations, relationships are established between this novel and current theoretical (literary lines.

  18. Comparison of nutrient uptake and their release in fern and grass stands on deforested areas in the Beskydy Mts

    Czech Academy of Sciences Publication Activity Database

    Tůma, Ivan; Fiala, Karel; Holub, Petr

    2005-01-01

    Roč. 18, - (2005), s. 73-78. ISBN 80-7157-297-7 R&D Projects: GA ČR(CZ) GA206/94/0385; GA ČR(CZ) GA526/97/0170 Institutional research plan: CEZ:AV0Z60050516 Keywords : decomposition * plant biomass * soil features Subject RIV: EF - Botanics

  19. Macrobenthos of Vembanad estuary in relation to the deposition of degraded water fern Salvinia and other macrophytes

    Digital Repository Service at National Institute of Oceanography (India)

    Gopalan, U.K.; Meenakshikunjamma, P.P.; Vengayil, D.T.

    were poorer in biomass and dominated by polychaetes A steady long term increase in the abundance of amphipods attaining the highest density of 70.290/m super(2), seems to be partly due to the progressive ingression of exogeneous macrophytic biomass...

  20. Uptake of zinc by Pteridium aquilinum (bracken fern) and response of Clarias gariepinus juveniles during chronic and sub lethal exposure.

    Science.gov (United States)

    Olaifa, F E; Fabusoro, A A

    2017-06-30

    Zinc is an essential trace element but can be toxic to fish at elevated concentrations. This study was carried out to assess the uptake of zinc by Clarias gariepinus juveniles and Pteridium aquilinum during chronic exposure to sub lethal concentrations. Two experiments were undertaken simultaneously in static renewal bioassays for 28 days.Haematology, histology, zinc accumulation in tissues of C.gariepinus and P. aquilinum were recorded fortnightly. Packed Cell Volume, haemoglobin concentration, Red Blood Cells, White blood cells, Lymphocytes, Neutrophils, Mean Corpuscular Volume, Mean Corpuscular Haemoglobin Concentration and Mean Corpuscular Haemoglobin of C. gariepinus varied with increasing exposure period. RBC, WBC, LYM, and NEUT differed significantly among treatments.

  1. Norsesquiterpene glycosides in bracken ferns (Pteridium esculentum and Pteridium aquilinum subsp. wightianum) from Eastern Australia: reassessed poisoning risk to animals.

    Science.gov (United States)

    Fletcher, Mary T; Brock, Ian J; Reichmann, Keith G; McKenzie, Ross A; Blaney, Barry J

    2011-05-11

    Austral bracken Pteridium esculentum contains three unstable norsesquiterpene glycosides: ptaquiloside, ptesculentoside, and caudatoside, in variable proportions. The concentration of each of the glycosides was determined in this study as their respective degradation products, pterosin B, pterosin G and pterosin A, by HPLC-UV analysis. Samples of P. esculentum collected from six sites in eastern Australia contained up to 17 mg of total glycoside/g DW, with both ptaquiloside and ptesculentoside present as major components accompanied by smaller amounts of caudatoside. Ratios of ptaquiloside to ptesculentoside varied from 1:3 to 4:3, but in all Australian samples ptesculentoside was a significant component. This profile differed substantially from that of P. esculentum from New Zealand, which contained only small amounts of both ptesculentoside and caudatoside, with ptaquiloside as the dominant component. A similar profile with ptaquiloside as the dominant glycoside was obtained for Pteridium aquilinum subsp. wightianum (previously P. revolutum ) from northern Queensland and also P. aquilinum from European sources. Ptesculentoside has chemical reactivity similar to that of ptaquiloside and presumably biological activity similar to that of this potent carcinogen. The presence of this additional reactive glycoside in Australian P. esculentum implies greater toxicity for consuming animals than previously estimated from ptaquiloside content alone.

  2. Changes in abiotic influences on seed plants and ferns during 18 years of primary succession on Puerto Rican landslides

    Science.gov (United States)

    Lawrence R. Walker; Aaron B. Shiels; Peter J. Bellingham; Ashley D. Sparrow; Ned Fetcher; Fred H. Landau; Deborah J. Lodge

    2013-01-01

    Abiotic variables are critical drivers of succession in most primary seres, but how their influence on biota changes over time is rarely examined. Landslides provide good model systems for examining abiotic influences because they are spatially and temporally heterogeneous habitats with distinct abiotic and biotic gradients and post-landslide erosion. In an 18-year...

  3. Description of synangia and spores of the holotype of the Carboniferous fern Lobatopteris miltoni, with taxonomic comments

    Czech Academy of Sciences Publication Activity Database

    Pšenička, J.; Bek, Jiří; Cleal, Ch. J.; Wittry, J.; Zodrow, E. L.

    2009-01-01

    Roč. 155, 3-4 (2009), s. 133-144 ISSN 0034-6667 R&D Projects: GA AV ČR IAA300130503 Institutional research plan: CEZ:AV0Z30130516 Keywords : Carboniferous * Marattiales * Lobatopteris * synangia * in situ spores Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.145, year: 2009

  4. In vitro tuberization of Chlorophytum Borivilianum Sant & Fern (Safed musli) as influenced by sucrose, CCC and culture systems.

    Science.gov (United States)

    Farshad Ashraf, Mehdi; Abd Aziz, Maheran; Abdul Kadir, Mihdzar; Stanslas, Johnson; Farokhian, Elmira

    2013-08-01

    This study focuses on the establishment of in vitro tuberization of Chlorophytum borivilianum using solid and liquid culture systems. A high in vitro tuberization rate on solid and stationary liquid Murashige and Skoog media was observed in the presence of 60 g l⁻¹ sucrose with 950, 1,265 and 1,580 µM 2-chloroethyl-trimethylammonium chloride (CCC). Application of a higher sucrose concentration of 90 g l⁻¹ showed a negative interaction with CCC on in vitro tuber number and days to in vitro tuber induction. For economic feasibility, 950 µM CCC with 60 g l⁻¹ sucrose was chosen as the best combination for in vitro tuberization in both solid and stationary liquid media. For optimization of in vitro tuber production,a comparison between solid, stationary liquid and shake liquid culture was carried out. Liquid culture with shaking at 80 r.p.m. resulted in a >2.5-fold increase in in vitro tuber production compared with solid culture.

  5. District heating systems - the necessary infrastructure for geothermal energy; Fern- und Nahwaermesysteme - notwendige Infrastruktur fuer die Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Schoenberg, I. [Inst. fuer Umwelt-, Sicherheits- und Energietechnik e.V. (UMSICHT), Oberhausen (Germany)

    1997-12-01

    The contribution discusses the future chances of geothermal energy use with cost-optimized systems of geothermal energy + cogeneration + district heating and with the focus on innovation instead of state funding. (orig./AKF) [Deutsch] Der Beitrag bezieht sich auf die zukuenftigen Chancen der Geothermie, die eine kostenoptimierte Systemloesung Geothermie + KWK + Nah-/Fernwaerme sowie durch Mut zur Innovation und nicht durch Foerderung bestimmt werden. (orig./AKF)

  6. La diversidad frente al espejo. Salud, interculturalidad y contexto migratorio (Gerardo Fernández Juárez, Dir.

    Directory of Open Access Journals (Sweden)

    Consuelo Álvarez Plaza

    2009-05-01

    Full Text Available El nacimiento de la Antropología de la Salud y la Enfermedad, en los años setenta del siglo pasado, supuso reconocer la enfermedad como fenómeno social y cultural, lo que equivale a cuestionar la naturalización, objetividad y universalidad del proceso de enfermar biomédico. A partir de aquí la antropología se sumerge en el pluralismo asistencial y la disciplina especializada comienza a constituir un cuerpo teórico y metodológico en torno a los procesos de salud, enfermedad y atención. Desde entonces la especialidad antropológica es de las más fructíferas en investigaciones y publicaciones multidisciplinarias.

  7. Double-deck trains for long-distance and high-speed services; Doppelstockzuege fuer den Fern- und Hochgeschwindigkeitsverkehr

    Energy Technology Data Exchange (ETDEWEB)

    Gaertner, H.

    2008-07-01

    The background underlying the development of double-deck trains in Europe was in most cases the need to envisage what would happen if on certain long-distance routes large numbers of passengers could no longer be carried in comfort on trains with the maximum permissible operating length. These maximum permissible train lengths could be conditioned inter alia by the available track of platform lengths as well as by operating conditions. What the railways demanded were a range of attractive solutions to the resultant design, comfort and operating problems. (orig.)

  8. A systemic gene silencing method suitable for high throughput, reverse genetic analyses of gene function in fern gametophytes

    Directory of Open Access Journals (Sweden)

    Tanurdzic Milos

    2004-04-01

    Full Text Available Abstract Background Ceratopteris richardii is a useful experimental system for studying gametophyte development and sexual reproduction in plants. However, few tools for cloning mutant genes or disrupting gene function exist for this species. The feasibility of systemic gene silencing as a reverse genetics tool was examined in this study. Results Several DNA constructs targeting a Ceratopteris protoporphyrin IX magnesium chelatase (CrChlI gene that is required for chlorophyll biosynthesis were each introduced into young gametophytes by biolistic delivery. Their transient expression in individual cells resulted in a colorless cell phenotype that affected most cells of the mature gametophyte, including the meristem and gametangia. The colorless phenotype was associated with a 7-fold decrease in the abundance of the endogenous transcript. While a construct designed to promote the transient expression of a CrChlI double stranded, potentially hairpin-forming RNA was found to be the most efficient in systemically silencing the endogenous gene, a plasmid containing the CrChlI cDNA insert alone was sufficient to induce silencing. Bombarded, colorless hermaphroditic gametophytes produced colorless embryos following self-fertilization, demonstrating that the silencing signal could be transmitted through gametogenesis and fertilization. Bombardment of young gametophytes with constructs targeting the Ceratopteris filamentous temperature sensitive (CrFtsZ and uroporphyrin dehydrogenase (CrUrod genes also produced the expected mutant phenotypes. Conclusion A method that induces the systemic silencing of target genes in the Ceratopteris gametophyte is described. It provides a simple, inexpensive and rapid means to test the functions of genes involved in gametophyte development, especially those involved in cellular processes common to all plants.

  9. Warnings to the far future. Radioactive wastes as a communications problem. Warnungen an die ferne Zukunft. Atommuell als Kommunikationsproblem

    Energy Technology Data Exchange (ETDEWEB)

    Posner, R. (Technische Univ. Berlin (Germany, F.R.). Arbeitsstelle fuer Semiotik) (ed.)

    1990-01-01

    Inquiries were launched in the USA, in Poland, France, Hungary, Brazil, and the Federal Republic of Gemany to find semiotic solutions to problems arising from the communication of radioactive waste locations and dangers to posteriority. How can information be communicated over a period of 10000 years What has been communicated to us from the past 10000 years It seems to be sure that neither natural nor artificial barriers nor remnants (e.g. skeletons) or sources (today's communication), but only explicit messages will keep intelligent creatures from intrusion into radioactive waste depositories. Among the subjects dealt with are: Pandora's box and how to prevent its opening; mathematical coding on living sign matter; living detectors and complementary signs: ray coat, broken eye, and nuclear sirens; the three-chamber system: a way to the democratic organization of collective knowledge and conscience which can survive millennia. (orig./HSCH).

  10. Occurrence of nutrients and plant hormones (cytokinins and IAA) in the water fern Salvinia molesta during growth and composting

    Czech Academy of Sciences Publication Activity Database

    Arthur, G. D.; Stirk, W. A.; Novák, Ondřej; Hekera, P.; van Staden, J.

    2007-01-01

    Roč. 61, č. 2 (2007), s. 137-144 ISSN 0098-8472 R&D Projects: GA MŠk(CZ) LC06034; GA ČR GA206/05/0894 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje Keywords : auxins * culture medium * cytokinins Subject RIV: BO - Biophysics Impact factor: 1.810, year: 2007

  11. Gene activity during germination of spores of the fern, Onoclea sensibilis: RNA and protein synthesis and the role of stored mRNA

    Science.gov (United States)

    Raghavan, V.

    1991-01-01

    Pattern of 3H-uridine incorporation into RNA of spores of Onoclea sensibilis imbibed in complete darkness (non-germinating conditions) and induced to germinate in red light was followed by oligo-dT cellulose chromatography, gel electrophoresis coupled with fluorography and autoradiography. In dark-imbibed spores, RNA synthesis was initiated about 24 h after sowing, with most of the label accumulating in the high mol. wt. poly(A) -RNA fraction. There was no incorporation of the label into poly(A) +RNA until 48 h after sowing. In contrast, photo-induced spores began to synthesize all fractions of RNA within 12 h after sowing and by 24 h, incorporation of 3H-uridine into RNA of irradiated spores was nearly 70-fold higher than that into dark-imbibed spores. Protein synthesis, as monitored by 3H-arginine incorporation into the acid-insoluble fraction and by autoradiography, was initiated in spores within 1-2 h after sowing under both conditions. Autoradiographic experiments also showed that onset of protein synthesis in the cytoplasm of the germinating spore is independent of the transport of newly synthesized nuclear RNA. One-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis of 35S-methionine-labelled proteins revealed a good correspondence between proteins synthesized in a cell-free translation system directed by poly(A) +RNA of dormant spores and those synthesized in vivo by dark-imbibed and photo-induced spores. These results indicate that stored mRNAs of O. sensibilis spores are functionally competent and provide templates for the synthesis of proteins during dark-imbibition and germination.

  12. Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata

    Directory of Open Access Journals (Sweden)

    Michael F Cohen

    2015-07-01

    Full Text Available In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared (SR-FTIR spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.

  13. Survey of ferns and clinico-pathological studies on the field cases of Enzootic bovine haematuria in Himachal Pradesh, a north-western Himalayan state of India

    DEFF Research Database (Denmark)

    Rai, Sarvesh K.; Sharma, Rinku; Kumari, Alka

    2017-01-01

    Enzootic bovine haematuria (EBH) in cattle occurs in upland areas of the world. In India, the disease is present in isolated pockets in the Himalayas and in the Nilgiri Hills. The variation in the disease incidence has been attributed to different environmental conditions and animal rearing...

  14. The fate of a colonizer: successful but lonely? The establishment of inter- and intra-specific diversity in ferns by means of long-distance dispersal

    NARCIS (Netherlands)

    de Groot, G.A.

    2012-01-01

    Global changes currently result in strong declines in species richness and population-genetic diversity. For maintenance of diversity in protected areas and developing new diversity in restored or newly created areas, immigration by long-distance dispersal (LDD) is of vital importance, as it allows

  15. Intracellular photoreceptive site for blue light-induced cell division in protonemata of the fern Adiantum [Pteridophyta]: Further analyses by polarized light irradiation and cell centrifugation

    International Nuclear Information System (INIS)

    Kadota, A.; Fushimi, Y.; Wada, M.

    1986-01-01

    The intracellular localization of the photoreceptive site for blue light-induced cell division in single-celled protonemata of Adiantum capillus-veneris L. was investigated using polarized light irradiation and protonemal cell centrifugation. The response to irradiation with polarized blue light showed no dependence on the direction of light polarization. However, centrifugation of the protonemata followed by microbeam irradiation showed that the site of blue light perception could be displaced together with the nucleus. Centrifugal treatment changed the distribution of intracellular organelles at the time of light exposure and basipetally displaced the nucleus about 90μm. This treatment had no effect on the induction of cell division with blue light if the protonemata were centrifuged again acropetally after the light treatment. Microbeam (30×30 μm2) irradiation with blue light of the apical 45–75 βm region, the receptive site of blue light in non-centrifuged cell, did not induce cell division. However, cell division was induced by irradiation of the nucleus-containing region, indicating that the photoreceptive site was displaced together with the nucleus by the centrifugation. These results suggest that the blue light receptor regulating cell division in Adiantum protonemata is not likely to be located on the plasma membrane. (author)

  16. Asplenium x sleepiae nothosubsp krameri (A-foreziense x A-obovatum subsp obovatum), a fern hybrid new for France (Aspleniaceae, Pteridophyta)

    NARCIS (Netherlands)

    Prelli, R; Rasbach, H; Viane, R

    1998-01-01

    A mixed population of several Asplenium taxa was studied near Roquebrune-sur-Argens (France, Var). A. foreziense, A. obovatum subsp. obovatum and A. obovatum subsp. lanceolatum were identified in the field and then confirmed by spore measurement. The presence of two hybrids within the population was

  17. F-22 Operational Squadron and T-38 Detachment Beddown at Tyndall Air Force Base, Florida

    Science.gov (United States)

    2011-08-01

    Rattlesnake Crotalus adamanteus Bracken Fern Pteridium aquilinum Six-lined Racerunner Cnemidophorus sexlineatus Blueberry Vaccinium spp. Florida Black Bear...adamanteus Bracken Fern Pteridium aquilinum Pileated Woodpecker Dryocopus pileatus Blackberry Rubus cuneifolius Pine Siskin Carduelis pinus Flatwoods

  18. In Memoriam G.J. de Joncheere (1909—1989)

    NARCIS (Netherlands)

    Kalkman, C.; Lut, C.W.J.

    1989-01-01

    On 8 January 1989 Gerardus Johannes de Joncheere died at the age of 79. He was an honorary staff member of the Fern section at the Rijksherbarium from 1974 to 1988, but his interest in Ferns dated already from before World War II. He always told that the purchase in 1939 of Backer & Posthumus, Fern

  19. Final Environmental Assessment for the High Explosive Research and Development Complex’s Proposed Long Term Upgrade and Expansion

    Science.gov (United States)

    2012-06-01

    panicum Pinus clausa Sand pine Pinus elliotii Slash pine Pinus palustris Long Leaf Pine Prunus sp. Scrub plum Pteridium aquilinum Bracken fern...fern ( Pteridium aquilinum ), partridge pea, southern magnolia, and turkey oak. The surface layer included British soldier lichen, scattered bracken...The scrub was dominated by sand pine (Pinus clausa), laurel oak (Quercus hemisphaerica), yaupon holly (Ilex vomitoria), bracken fern ( Pteridium

  20. Chemical composition of the essential oils of three endemic species of Anthemis Sect. Hiorthia (DC.) R.Fern. growing wild in Sicily and chemotaxonomic volatile markers of the genus Anthemis L.: an update.

    Science.gov (United States)

    Maggio, Antonella; Riccobono, Luana; Spadaro, Vivienne; Scialabba, Anna; Bruno, Maurizio; Senatore, Felice

    2014-04-01

    The chemical composition of the essential oils isolated from the aerial parts of Anthemis pignattiorum Guarino, Raimondo & Domina and A. ismelia Lojac. and the aerial parts and flowers of Anthemis cupaniana Tod. ex Nyman, three endemic Sicilian species belonging to the section Hiorthia, was determined by GC-FID and GC/MS analyses. (Z)-Muurola-4(14),5-diene (27.3%) was recognized as the main constituent of the A. pignattiorum essential oil, together with isospathulenol (10.6%), sabinene (7.7%), and artemisyl acetate (6.8%), while in the oil obtained from the aerial parts of A. ismelia, geranyl propionate (8.8%), bornyl acetate (7.9%), β-thujone (7.8%), neryl propionate (6.5%), and τ-muurolol (6.5%) prevailed. α-Pinene was the main compound of both the aerial part and flower oils of A. cupaniana (18.4 and 13.2%, resp.). Also noteworthy are the considerable amounts of artemisyl acetate (12.7%) and β-thujone (11.8%) found in the oil from the aerial parts and those of tricosane (9.8%) and sabinene (7.6%) evidenced in the flower oil. Furthermore, an update on the main compounds identified in the essential oils of all the Anthemis taxa studied so far was presented, and cluster analyses were carried out, to compare the essential oils of these taxa. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

  1. An handwritten signature, previous owners and circulation of a copy of Gonzalo Fernández de Oviedo’s book ‘About the Natural History of the Indies’

    Directory of Open Access Journals (Sweden)

    Júlio Manuel Rodrigues Costa

    2017-06-01

    Full Text Available This research note aims to disclose a copy of Oviedo’s About the natural history of the Indies, also known as Summary of the natural history, published in Toledo in 1526 and currently under the custody of Municipal Library of Porto, Portugal. Special features of this copy are presented: author’s handwritten signature and some ownership marks that allow us to identify previous owners, the connections between them and to track book circulation.

  2. Matar al Chino. Entre la revolución urbanística y el asedio urbano en el barrio del Raval de Barcelona, de Miquel Fernández González

    Directory of Open Access Journals (Sweden)

    Livia Motterle

    2015-05-01

    Full Text Available El mito es el resultado de una fabricación que mezcla de forma indisoluble la realidad con la imaginación. Desmantelar un mito, comprender las razones, las modalidades y los fines de su fabricación llega a ser por lo tanto tarea muy noble y al mismo tiempo muy compleja. Se trata no solamente de desvelar los procesos de deshistorización de la dominación de una sociedad sobre otras para reconstruir aquella historia fragmentada, ocultada o distorsionada en los discursos hegemónicos, sino que el cazador de mitos asume la intrépida «misión» de restituir a los colectivos mitifi cados su propia humanidad robada. Matar al Chino. Entre la revolución urbanística y el asedio urbano en el barrio del Raval constituye un excelente ejemplo de cómo lograr esta tarea.

  3. Tree and tree-like species of Mexico: gymnosperms, monocotyledons, and tree ferns Especies arbóreas y arborescentes de México: gimnospermas, monocotiledóneas y helechos arborescentes

    Directory of Open Access Journals (Sweden)

    Martin Ricker

    2010-04-01

    Full Text Available Trees or tree-like plants are defined here broadly as perennial, self-supporting plants with an adult height of at least 5 m (without ascending leaves or inflorescences, and with 1 or several erect stems with a diameter of at least 10 cm. We present an updated list of all Mexican tree species under that definition in the Gymnospermae (86 species, 38% endemic to Mexico, Monocotyledonae (75 species, 55% endemic, and Pteridophyta (9 species, none endemic. The list contains a total of 170 species in 37 genera and 12 families, with 74 species (44% being endemic to Mexico. The list was compiled consulting recent literature, the National Herbarium of Mexico (MEXU, and taxonomic specialists.Las plantas arbóreas o arborescentes se definen aquí en un sentido amplio como plantas perennes que se pueden sostener por sí solas, con una altura del adulto de al menos 5 m (sin considerar hojas o inflorescencias ascendentes, y con 1 o varios tallos erectos de un diámetro de al menos 10 cm. Presentamos aquí una lista actualizada bajo esta definición de todas las especies arbóreas mexicanas que pertenecen a las Gymnospermae (86 especies, 38% endémicas de México, Monocotyledonae (75 especies, 55% endémicas, y Pteridophyta (9 especies, ninguna endémica. La lista contiene un total de 170 especies en 37 géneros y 12 familias, con 74 especies (44% endémicas de México. La lista fue compilada al consultar fuentes bibliográficas recientes, el Herbario Nacional de México (MEXU, y taxónomos especialistas.

  4. Gene activity during germination of spores of the fern, Onoclea sensibilis. Cell-free translation analysis of mRNA of spores and the effect of alpha-amanitin on spore germination

    Science.gov (United States)

    Raghavan, V.

    1992-01-01

    Poly(A)-RNA fractions of dormant, dark-imbibed (non-germinating) and photoinduced (germinating) spores of Onoclea sensibilis were poor templates in the rabbit reticulocyte lysate protein synthesizing system, but the translational efficiency of poly(A)+RNA was considerably higher than that of unfractionated RNA. Poly(A)+RNA isolated from photoinduced spores had a consistently higher translational efficiency than poly(A)+RNA from dark-imbibed spores. Analysis of the translation products by one-dimensional polyacrylamide gel electrophoresis showed no qualitative differences in the mRNA populations of dormant, dark-imbibed, and photoinduced spores. However, poly(A)+RNA from dark-imbibed spores appeared to encode in vitro fewer detectable polypeptides at a reduced intensity than photoinduced spores. A DNA clone encoding the large subunit of maize ribulose bisphosphate carboxylase hybridized at strong to moderate intensity to RNA isolated from dark-imbibed spores, indicating the absence of mRNA degradation. Although alpha-amanitin did not inhibit the germination of spores, the drug prevented the elongation of the rhizoid and protonemal initial with a concomitant effect on the synthesis of poly(A)+RNA. These results are consistent with the view that some form of translational control involving stored mRNA operates during dark-imbibition and photoinduced germination of spores.

  5. El conocimiento de los records como motivación en la preparación del equipo permanente de atletismo de la ESBU Antero Fernández Vargas del municipio San Juan y Martínez

    Directory of Open Access Journals (Sweden)

    José Manuel Vives Morejón

    2009-09-01

    Full Text Available Ha sido en los últimos años la introducción del deporte participativo, una de las vías que facilite a la gran masa estudiantil la práctica del deporte de forma masiva y organizada. Los profesores preparan a sus alumnos en los deportes según el nivel de enseñanza, lo que representa un gran estimulo para el profesor de Educación Física y sus alumnos, los cuales transitan desde la base hasta el nivel nacional, de ahí que se necesite conocer el estado en que se encuentran sus alumnos desde el punto de vista físico, deportivo y motivacional. El atletismo es uno de los deportes que está presente en todos los niveles de participación, pero en nuestra escuela ocupa el último lugar dentro de la preferencia de los estudiantes, lo que nos incitó investigar al respecto con vistas a lograr niveles óptimos de motivación para la práctica sistemática de este deporte, de ahí que durante la realización de las pruebas de eficiencia física, competencias mensuales de atletismo, deporte participativo, hemos recopilado cada uno de los eventos y diseñado en el centro un sistema de estimulación desde la clase, el mural de educación física y los actos centrales de la escuela para dar a cono cer los mejores resultados, quedando establecidos como records dentro de la escuela de forma permanente, esto ha motivado a los estudiantes a querer conocer sus potencialidades en cada uno de los eventos y si han superado los resultados alcanzados por los estudiantes en cursos anteriores, lo que se ha convertido en un recurso importante para estimular la preparación de los integrantes del equipo de atletismo de nuestra escuela, donde todos quieren estar en el equipo y entre los recordistas del centro.

  6. Eloy Fernández Porta y la condición afterpop : metodologías analíticas y estrategias artísticas ante la fabricación de la subjetividad

    OpenAIRE

    Tarancón Royo, Héctor

    2015-01-01

    Como resultado de los últimos desarrollos de los medios de reproducción y distribución de imágenes, la cultura de masas surge a principios del siglo XX y rede fi ne a lo largo de toda la centuria el modo de consumo el estatuto del arte y las maneras de percepción de su sociedad de una manera irrecuperable. Aún más, con el auge de internet y la creciente fragmentación de los movimientos culturales, la cultura de masas se expande ...

  7. Intervención\tcomunitaria\tcon\tla\ttécnica\tdel\t“ORIGAMI”\ten la ESBU “Ceferino Fernández Viñas” del municipio de Pinar del Río

    Directory of Open Access Journals (Sweden)

    Sergio Abel Suárez García

    2009-12-01

    Full Text Available En nuestro trabajo pretendemos proponer una metodología para la enseñanza del “Origami”, como técnica que pueda ser usada por los docentes en los centro educacionales de la provincia, representando como algo de gran utilidad y que se complementa con la técnica de los audiovisuales que generan pasividad en los estudiantes; es una manera de favorecer el desarrollo integral, entiéndase cognitivo, emocional, físico, además de modificar conductas inadecuadas y mejorar los comportamientos en los centros educacionales y la comunidad. El uso de los materiales que son utilizados en la elaboración del medio, son materiales recuperados de fácil adquisición, logrando con ellos darle riendas sueltas al pensamiento creativo de los estudiantes, obteniendo unidad entre ciencia, arte y ejercicios manuales; podemos además con ellos embellecer nuestro entorno, ambiente y considerarse admirados por lo que hemos creado, contribuyendo con esta técnica a la armonía general del estudiante y de quienes comparten con ellos la dinámica y convivencia en los centros educacionales.

  8. A plant developmental system to measure the impact of pollutants in rain water

    Energy Technology Data Exchange (ETDEWEB)

    Evans, L.S.

    1979-11-01

    Unique experimental methods to measure effects of toxicants in water solutions on syngamy in bracken fern (Pteridium aquilinum) are described. The effects of aqueous solutions with and without various anions on spermatozoid motility and syngamy and sporophyte production are tested. Fertilization and spermatozoid motility in gametophytes of bracken fern are very sensitive to low pH and additions of sulfate, nitrate, and chloride. Fertilization in bracken fern may be a good indicator of pollutants in rainwater. 20 references, 4 tables.

  9. The potential of Thelypteris palustris and Asparagus sprengeri in phytoremediation of arsenic contamination.

    Science.gov (United States)

    Anderson, LaShunda L; Walsh, Maud; Roy, Amitava; Bianchetti, Christopher M; Merchan, Gregory

    2011-02-01

    The potential of two plants, Thelypteris palustris (marsh fern) and Asparagus sprengeri (asparagus fern), for phytoremediation of arsenic contamination was evaluated. The plants were chosen for this study because of the discovery of the arsenic hyperaccumulating fern, Pteris vittata (Ma et al., 2001) and previous research indicating asparagus fern's ability to tolerate > 1200 ppm soil arsenic. Objectives were (1) to assess if selected plants are arsenic hyperaccumulators; and (2) to assess changes in the species of arsenic upon accumulation in selected plants. Greenhouse hydroponic experiments arsenic treatment levels were established by adding potassium arsenate to solution. All plants were placed into the hydroponic experiments while still potted in their growth media. Marsh fern and Asparagus fern can both accumulate arsenic. Marsh fern bioaccumulation factors (> 10) are in the range of known hyperaccumulator, Pteris vittata Therefore, Thelypteris palustris is may be a good candidate for remediation of arsenic soil contamination levels of asparagus fern. The asparagus fern is arsenic tolerant (bioaccumulation factors < 10), but is not considered a good potential phytoremediation candidate.

  10. 12. Negripteridaceae

    DEFF Research Database (Denmark)

    Friis, Ib

    2009-01-01

    A taxonomic revision of and a floristic account of the species of the fern family Negripteridaceae recorded from Ethiopia and Eritrea.......A taxonomic revision of and a floristic account of the species of the fern family Negripteridaceae recorded from Ethiopia and Eritrea....

  11. 14. Cryptogrammaceae

    DEFF Research Database (Denmark)

    Friis, Ib

    2009-01-01

    A taxonomic revision and a floristic account of all species of the fern family Cryptogrammaceae recorded from Ethiopia and Eritrea......A taxonomic revision and a floristic account of all species of the fern family Cryptogrammaceae recorded from Ethiopia and Eritrea...

  12. 13. Sinopteridaceae

    DEFF Research Database (Denmark)

    Friis, Ib

    2009-01-01

    A taxonomic revision of and a floristic account of all species in the fern family Sinopteridaceae recorded from Ethiopia and Eritrea......A taxonomic revision of and a floristic account of all species in the fern family Sinopteridaceae recorded from Ethiopia and Eritrea...

  13. 26. Thelypteridaceae

    DEFF Research Database (Denmark)

    Friis, Ib

    2009-01-01

    A taxonomic revision and a floristic account of all species of the fern family Thelypteridaceae recorded from Ethiopia and Eritrea......A taxonomic revision and a floristic account of all species of the fern family Thelypteridaceae recorded from Ethiopia and Eritrea...

  14. Environmental Assessment: Relocation of Facilities at Hurlburt Field, Florida

    Science.gov (United States)

    2011-11-01

    fern ( Pteridium aquilinum ), and highbush blueberry (Vaccinium corymbosum). The access road route to the NE Area proposed under Alternatives 1 and 2...bracken fern ( Pteridium aquilinum ), and highbush blueberry (Vaccinium corymbosum). The NE Area is surrounded entirely by a large forested wetland

  15. Bio-Physicochemical Interactions of Engineered Nanomaterials in in Vitro Cell Culture Model

    Science.gov (United States)

    2014-10-11

    cultured BEAS-2B cells. Toxicology 245, 90–100. Rosenkranz P, Fernández- Cruz M L, Conde E, Ramírez-Fernández MB, Flores JC, Papis E, Rossi F, Raspanti M...public release; distribution is unlimited. 31    Tice, R. R., Agurell, E., Anderson, D., Burlinson, B., Hartmann, A., Kobayashi, H., Miyamae, Y., Rojas , E

  16. Wine instability. I. The importance of the wine proteins

    OpenAIRE

    Mesquita, P.R.; Monteiro, S.; Pereira, M.A.P.; Loureiro, V.B.; Teixeira, A.; Ferreira, R.B.

    1999-01-01

    The present work consisted in the removal of protein from six Portuguese varietal wines (Fernão Pires, Assario, Tamarez, verdelho, Arinto and Moscatel)by bentonite fining and subsequent haze induction using the back-addition technique of the total protein from Fernão Pires wine.

  17. The Evaluation of High Resolution Aerial Imagery for Monitoring of ...

    African Journals Online (AJOL)

    The Royal Natal National Park and the Rugged Glen Nature Reserve are part of the uKhahlamba Drakensberg Park (UDP) World Heritage Site and have infestations of bracken fern (Pteridium aquilinum [L.] Kuhn). Prior image classification research on bracken fern were constrained by low resolution satellite imagery and ...

  18. Tonawanda Creek, Genesee County, New York, Regional Flood Control. Final Environmental Impact Statement.

    Science.gov (United States)

    1981-11-01

    Linarea vulgaris Wild Mustard :Brasica sp. Sensitive Fern :Onoclea sensibilis *Christmas Fern :As21dium acrostichoides Panic Grass :Panicum sp. Barnyard... Sciurus carolinensis Reptiles E ’tern Painted Turtle :Chrysemys picta picta Birds Mallard :Anas platyrhynchos Black Duck :Anas rubripes Ring-necked...migratorius migratorius Starling :Sturnus vulgaris Eastern Golden-crowned Kinglet :Regulus satrapa satrapa Rusty Blackbird :Euphagus carolinus Red

  19. Download this PDF file

    African Journals Online (AJOL)

    USER

    453 of Human Evolution39:381-391. Rothwell, G.W. and Stockey, R.A. 2008. Phylogeny and evolution of ferns: a paleontological perspective. In: Biology and Evolution of. Ferns and Lycophytes, (eds.), T.A. Ranker, and C.H. Haufler. Cambridge University. Press 332-366pp. Sharpe, J.M., Mehltreter, K. and Walker, L.R. 2010.

  20. Group-size effect on scanning behaviour of Maasai Ostrich Struthio ...

    African Journals Online (AJOL)

    Flocking and predator surveillance in House Sparrows: test of a hypothesis. Animal Behaviour 29: 868–872. Fernández-Juricic, e., SmiTh, r. & kaceLnik, a. 2005. Increasing the costs of conspecific scanning in socially foraging starlings affects vigilance and foraging behaviour. Animal Behaviour 69: 73–81. Fernández-Juricic ...

  1. Expeditions and other fieldwork

    NARCIS (Netherlands)

    NN,

    1987-01-01

    Mssrs. L.G. SAW and K.M. WONG (KEP) collected further in the Endau-Rompin forests of Johore during April and June 1986. Ms. Dr. B.S. PARRIS (K) spent August 1986 based at FRIM collecting fern material and studying fern diversity in montane forests. Together with Mr. K.M. WONG (KEP) she visited the

  2. Evaluation of Glucosidase Inhibitory and Cytotoxic Potential of Five ...

    African Journals Online (AJOL)

    Purpose: To evaluate the glucosidase inhibitory and cytotoxic activities of five selected edible and medicinal ferns, namely, Blechnum orientale, Davallia denticulata, Diplazium esculentum, Nephrolepis biserrata, and Pteris vittata. Methods: The aqueous extracts of the five ferns were prepared by water extraction at 90 ºC for ...

  3. Javier Fernández Sebastián (dir.): Diccionario político y social del mundo iberoamericano. Conceptos políticos fundamentales, 1770-1870, Madrid: Centro de Estudios Políticos y Constitucionales – Universidad del País Vasco, 2014, tomo II, en 10 vols

    OpenAIRE

    Simal, Juan Luis

    2015-01-01

    Escribir una reseña de una obra monumental de más de 2.000 páginas, en la que han colaborado 98 autores provenientes de todo el espacio iberoamericano, Estados Unidos y otros países europeos, y que completa una publicación previa de semejantes dimensiones, no es solo una tarea difícil, sino que se antoja ilusoria. Intentaré ofrecer algunas reflexiones al respecto

  4. Ocupación del tiempo libre en los jóvenes en edades de 16-18 años del Consejo Popular “Ceferino Fernández” en el municipio Pinar del Río

    Directory of Open Access Journals (Sweden)

    Yoel Álvarez Rodríguez

    2009-06-01

    Full Text Available Las  personas  necesitan  cada  vez  más  de  estos  servicios  a  la  vez  que  se convierten en una necesidad, no solo, en nuestro pueblo sino en todo el mundo, para lograr estos objetivos se hace necesaria una correcta planificación que responda a los intereses recreativos, teniendo en cuenta que proporciona. Desarrollo multifacético, en los niños jóvenes y adultos. Cuba se ha propuesto ser el país más culto del planeta y para ello, el trabajo con la cultura es primordial, así como el trabajo ideológico, artístico , deportivo y de educación general e integral, respondiendo como siempre a los intereses de la sociedad, para así contribuir a aumentar los niveles de calidad de vida. La persona es sin discusión el elemento principal de la sociedad y sobre todo en un  sistema  socialista  como  el  nuestro,  que  se  articula  activamente  a  esta, cargando con las necesidades, expectativas e intereses que tienen, y que intenta satisfacer con la vivencia de  actividades. En este proceso el área de recursos humanos y específicamente la de Bienestar Social, han de dedicar esfuerzos encaminados  a la compresión y estructuración de  modos  de  generar  satisfacciones  de  las  necesidades  humanas,  de  las motivaciones de las personas, la disminución de la rutina, las actividades fuera del entorno laboral, los planes de beneficio social y la búsqueda de factores estimulantes en el trabajo y la comunidad, aspectos que han constituido dentro del campo de la salud ocupacional como factores de riesgo biopcicosocial en las organizaciones y el conocimiento de la psicología del ser humano

  5. Mensuration of sialic acid seric level in nelore cattle exposed and nonexposed to bracken fern (Pteridium aquilinum / Aferição da concentração sérica de ácido siálico em novilhas da raça nelore expostas e não expostas à samambaia (Pteridium aquilinum

    Directory of Open Access Journals (Sweden)

    Wilmar Sachetin Marçal

    2008-08-01

    Full Text Available The Pteridium aquilinum is one toxic plant present in several countries of the world. The chronic ingestion causes diseases to livestock with negative economics repercussion. In Paraná state the Pteridium aquilinum is present in 105 out 399 municipal districts existents. The high occurrence of the plant in many areas of the Paraná state and the wrong utilization of these areas for cattle breed increase the importance of research that look for means that epidemic control of intoxication. Because that research institutions in the Paraná state have looking for means to advance in diagnosis methods, especially to cattle suffering from Bovine Enzootic Hematuria. The biomarkers have been used in the diagnosis and postoperative follow-up of tumor in the human beings in a routinely bases for years. Researches about this subject were crescent in the medicine of companion animals, however still incipient about cattle. Specifically in the Bovine Enzootic Hematuria were verified that mucin, a substance present in the mucus from the mucosal surface of bladder, is produced by tumoral cells in reasonable accounts. Previous reports verified one relationship between the excessive mucus protein production by the bladder with hemangioma and high plasmatic concentration of the sialic acid. This suggests that sialic acid is associated with inflammatory response of the tumoral growth, and might be used such as tumoral biomarker.A Pteridium aquilinum é uma planta tóxica, disseminada em vários paises do mundo, cuja ingestão continua resulta em doenças com impacto negativo à pecuária bovina. No Paraná, esta presente em 105 dos 399 municípios do Estado. Por essa razão tem-se buscado por meios de controle epidemiológico da intoxicação, já que em algumas localidades do Paraná a planta está disseminada em muitas áreas utilizadas para cria e recria de bovinos. Assim sendo, as instituições de pesquisa do Estado têm buscado meios de diagnóstico precoce, sobretudo da forma clinica Hematúria Enzoótica dos Bovinos. Biomarcadores têm sido utilizados na rotina médica, há anos, para o diagnóstico e controle pós-operatório de pacientes com neoplasias. O numero de publicações nesta linha na medicina de animais de companhia tem sido crescente, porém, o tema ainda é pouco estudado como parte da abordagem diagnóstica de bovinos de corte. No caso específico da Hematúria Enzoótica dos Bovinos, estudos prévios comprovaram que a mucina, substancia presente no muco vesical, é produzida em quantidades consideráveis na superfície das células tumorais. Estudos prévios apontaram uma relação entre a produção excessiva de mucoproteína em animais com hemangioma de bexiga e a concentração plasmática do ácido siálico, comprovando que o ácido siálico é uma substancia associada ao processo inflamatório do desenvolvimento tumoral, o que sugere a possibilidade de seu uso como biomarcador tumoral.

  6. Never conclude with a negative result, explore all possibilities before changing your hypothesis. An interview with Dr. Catherine Figarella, former Director Groupe de Recherche sur les Glandes Exocrines, Faculté de Médecine, Marseille, France; Active Member of the Board of the French Cystic Fibrosis Association: 'Vaincre la Mucoviscidose'. Interview by Martín E. Fernández-Zapico.

    Science.gov (United States)

    Figarella, Catherine

    2010-01-01

    Dr. Catherine Figarella is a world expert in the isolation and characterization of human exocrine pancreatic proteins (enzymatic and non-enzymatic ones). She was a pioneer in the identification and characterization of the numerous zymogens present in pancreatic juice. In particular, her discovery of a peculiar behavior of one of the main proteolytic zymogens: human trypsinogen 1, which was more readily activated into active trypsin than human trypsinogen 2 and trypsinogens of other species led her to propose that a premature intracellular activation of this zymogen may play a role in the pathogenesis of chronic pancreatitis. She demonstrated that a similar phenomenon may occur in cystic fibrosis (CF) and has applied this knowledge of pancreatic zymogens to follow the evolution of the pancreatic disease in CF. With this brief but keen biographical article Dr. Figarella shares her life experience as an innovative medical and biochemical investigator of human exocrine pancreatic function. Copyright 2010 S. Karger AG, Basel.

  7. Modeling a scientific career: an essential component of the mentorship process. An interview with John A. Williams, Professor of Molecular and Integrative Physiology, University Of Michigan, Ann Arbor, Mich., USA by Martín E. Fernández-Zapico.

    Science.gov (United States)

    Williams, John A

    2010-01-01

    In the current interview article, Dr. John A. Williams shares his experiences, and provides career advice to junior investigators. Dr. Williams is one of the world's leading physiologists working on signal transduction mechanisms in pancreatic acinar cells. He is worldwide recognized for his contribution to many areas of pancreatology, especially the understanding of GI hormone regulation of pancreatic exocrine function. and IAP.

  8. Inauguración de los nuevos edificios de las Facultades de Humanidades y Ciencias de la Educación y de Psicología de la UNLP : Acto de inauguración con la presencia de la presidenta de la nación, Cristina Fernández de Kirchner

    OpenAIRE

    Fernández de Kichner, Cristina

    2014-01-01

    Radio Universidad transmite en directo y registra el acto de inauguración de los nuevos edificios de las facultades de Humanidades y Ciencias de la Educación y de Psicología de la UNLP, levantados en el predio que ocupara el Batallón de Infantería de Marina Nº 3, donde durante la última dictadura funcionara un centro clandestino de detención. Se escucha el audio de un video referido al Programa de Recuperación Edilicia de la UNLP, en el marco del Proyecto Nacional de Infraestructura Univer...

  9. Revisión crítica de una interpretación del pensamiento de virginia Henderson: Acercamiento epistemológico al libro de Luis, Fernández y Navarro Critical revision of one interpretation of the thought of Virginia Henderson: epistemological approach to the book of Luis, Fernandez and Navarro

    Directory of Open Access Journals (Sweden)

    Xabier Irigibel-Uriz

    2007-09-01

    Full Text Available La construcción teórica en enfermería se presenta como el camino por donde deben acontecer las transformaciones de la disciplina. En ese caminar este artículo tiene por objetivo contribuir al debate de la adecuación o no de la teoría de Virginia Henderson, así como de la interpretación que se hace de la misma. Para ello y por medio de la metodología historicista, se realiza un acercamiento epistemológico del libro "De la teoría a la práctica, el pensamiento de Virginia Henderson en el siglo XXI", escrito por tres enfermeras docentes de la Universidad de Barcelona. Los resultados ofrecen una lucha paradigmática en la que la ideología que impregna a las autoras dificulta una concepción innovadora de los Metaparadigmas de enfermería.The theoretical construction as it relates to nursing, presents itself as the way where all disciplinary transformations happen. Within the context of this particular way, the article contributes to the debate regarding the suitability or not of Virginia Henderson’s theory, as well as its interpretation. For this purpose, using the Historicism methodology, an epistemological approach is used towards "From theory to practice, Virginia Henderson’s approach in the XXI century", book written by three nurses, teachers at the University of Barcelona. The conclusions this article presents, offer a paradigm, a struggle, where the ideology which impregnates the authors, make difficult the conception of innovative metaparadigms in nursing.

  10. Coleccion de los viajes y descubrimientos que hicieron por mar los españoles desde fines del siglo XV : con varios documentos inéditos concernientes á la historia de la Marina Castellana y de los Establecimientos Españoles de Indias / coordinada e ilustrada por Martín Fernández de Navarrete..

    OpenAIRE

    2016-01-01

    5 v. : 2 lám ; 21 cm + mapas 2ª ed. V. 1 (1853): Viajes de Colón ; Almirantazgo de Castilla.-- V. 2 (1859): Documentos de Colón y de las primeras poblaciones.-- V. 3 (1880): Viajes menores y los de Vespucio ; Poblaciones en el Darien.-- Suplemento al T. 2.-- V. 4 (1837): Expediciones al Maluco ; Viaje de Magallanes y de Elcano.-- V. 5 (1837): Expediciones al Maluco ; Viajes de Loaisa y Saavedra.

  11. Sexual compatibility among different host-originated isolates of Aphelenchoides besseyi and the inheritance of the parasitism.

    Directory of Open Access Journals (Sweden)

    Shu-Hua Hsieh

    Full Text Available Nine isolates of Aphelenchoides besseyi from two different hosts were studied. The isolates were identified at the species level according to morphometrics and fine structures observed under a scanning electron microscope. Two fern-originated isolates, Fu, and Fm, one rice-originated isolate, Rl, were not able to reproduce from a single juvenile, based on at least 50 replicates. The other six isolates were able to develop into a small population when inoculated with a single juvenile, demonstrating parthenogenesis. Crosses between isolates were conducted. In a compatibility cross experiment, three fern-originated isolates were selfed and crossed reciprocally, and all nine crossings had viable offspring. When fern isolates were used as paternal lines, the only two successful crosses were with the Rd line, and as maternal lines, only the Ff x Re and Fu x Rn crosses had viable offspring. Rl was used as the maternal line and Fm as the paternal line to study the inheritance of the bird's-nest fern parasitism. Twenty of the 80 attempted crosses resulted in viable offspring and among these; six lines had the ability to parasitize on the bird's-nest fern. When the F(1 lines were back-crossed to the Rl maternal line, 20 viable offspring lines were obtained and among them 4 were able to parasitize bird's-nest fern. These results indicate that bird's-nest fern parasitism can be transferred to new generations by cross fertilization.

  12. Evolutionary Conservation of ABA Signaling for Stomatal Closure1[OPEN

    Science.gov (United States)

    Huang, Yuqing; Dai, Fei; Franks, Peter J.; Nevo, Eviatar; Soltis, Douglas E.; Soltis, Pamela S.; Xue, Dawei; Zhang, Guoping; Pogson, Barry J.

    2017-01-01

    Abscisic acid (ABA)-driven stomatal regulation reportedly evolved after the divergence of ferns, during the early evolution of seed plants approximately 360 million years ago. This hypothesis is based on the observation that the stomata of certain fern species are unresponsive to ABA, but exhibit passive hydraulic control. However, ABA-induced stomatal closure was detected in some mosses and lycophytes. Here, we observed that a number of ABA signaling and membrane transporter protein families diversified over the evolutionary history of land plants. The aquatic ferns Azolla filiculoides and Salvinia cucullata have representatives of 23 families of proteins orthologous to those of Arabidopsis (Arabidopsis thaliana) and all other land plant species studied. Phylogenetic analysis of the key ABA signaling proteins indicates an evolutionarily conserved stomatal response to ABA. Moreover, comparative transcriptomic analysis has identified a suite of ABA-responsive genes that differentially expressed in a terrestrial fern species, Polystichum proliferum. These genes encode proteins associated with ABA biosynthesis, transport, reception, transcription, signaling, and ion and sugar transport, which fit the general ABA signaling pathway constructed from Arabidopsis and Hordeum vulgare. The retention of these key ABA-responsive genes could have had a profound effect on the adaptation of ferns to dry conditions. Furthermore, stomatal assays have shown the primary evidence for ABA-induced closure of stomata in two terrestrial fern species P. proliferum and Nephrolepis exaltata. In summary, we report, to our knowledge, new molecular and physiological evidence for the presence of active stomatal control in ferns. PMID:28232585

  13. Effects of compost and phosphate amendments on arsenic mobility in soils and arsenic uptake by the hyperaccumulator, Pteris vittata L

    International Nuclear Information System (INIS)

    Cao Xinde; Ma, Lena Q.; Shiralipour, Aziz

    2003-01-01

    Chinese brake fern (Pteris vittata L.), an arsenic (As) hyperaccumulator, has shown the potential to remediate As-contaminated soils. This study investigated the effects of soil amendments on the leachability of As from soils and As uptake by Chinese brake fern. The ferns were grown for 12 weeks in a chromated-copper-arsenate (CCA) contaminated soil or in As spiked contaminated (ASC) soil. Soils were treated with phosphate rock, municipal solid waste, or biosolid compost. Phosphate amendments significantly enhanced plant As uptake from the two tested soils with frond As concentrations increasing up to 265% relative to the control. After 12 weeks, plants grown in phosphate-amended soil removed >8% of soil As. Replacement of As by P from the soil binding sites was responsible for the enhanced mobility of As and subsequent increased plant uptake. Compost additions facilitated As uptake from the CCA soil, but decreased As uptake from the ASC soil. Elevated As uptake in the compost-treated CCA soil was related to the increase of soil water-soluble As and As(V) transformation into As(III). Reduced As uptake in the ASC soil may be attributed to As adsorption to the compost. Chinese brake fern took up As mainly from the iron-bound fraction in the CCA soil and from the water-soluble/exchangeable As in the ASC soil. Without ferns for As adsorption, compost and phosphate amendments increased As leaching from the CCA soil, but had decreased leaching with ferns when compared to the control. For the ASC soil, treatments reduced As leaching regardless of fern presence. This study suggest that growing Chinese brake fern in conjunction with phosphate amendments increases the effectiveness of remediating As-contaminated soils, by increasing As uptake and decreasing As leaching. - Phosphate amendment increases the effectiveness of Chinese brake fern to remediate As-contaminated soils, by increasing As uptake and decreasing As leaching

  14. BROWN SPOT CAUSED BY CURVULARIA SPP., A NEW DISEASE OF ASPARAGUS

    Directory of Open Access Journals (Sweden)

    B. SALLEH

    1996-01-01

    Full Text Available The distribution, aetiology and symptomatology of a new disease on asparagus ferns, which we have termed brown spot, is described. Descriptions of and a key to identification of the causal organisms, Curvularia brachyspora, C. eragrostidis, C. lunata and C. pallescens, are also presented. Pathogenicity tests showed that C. lunata was the dominant and most virulent of the four species. Inoculation with conidial suspensions or mycelial transfers through wounded ferns were more effective in inducing the disease than inoculations on unwounded ferns. This is the first record of C. brachyspora in Malaysia and the first report of this disease on asparagus.

  15. ERLN Biological Focus Area

    Science.gov (United States)

    The Environmental Response Laboratory Network supports the goal to increase national capacity for biological analysis of environmental samples. This includes methods development and verification, technology transfer, and collaboration with USDA, FERN, CDC.

  16. A new species of Odontosoria (Lindsaeaceae) from New Guinea

    NARCIS (Netherlands)

    Lehtonen, S.

    2011-01-01

    A new fern species, Odontosoria quadripinnata, is described from New Guinea. The new species resembles O. retusa, but has quadripinnate laminas, short sori and monolete spores in contrast to tripinnate laminar division, continuous sori and trilete spores in O. retusa.

  17. La seguridad alimentaria en el África Subsahariana y la cooperación Sur-Sur brasileña en materia agrícola: potencialidades y límites

    OpenAIRE

    De Andrade e Sousa, Maria Eduarda

    2014-01-01

    Treballs finals del Màster "Estudios Internacionales: organizaciones internacionales y cooperación – Colección Memorias MEI", Facultat de Dret, Universitat de Barcelona, Curs:2013-2014 , Director: Xavier Fernández Pons

  18. Interfaces of regeneration, structure, diversity and uses of some ...

    African Journals Online (AJOL)

    ferns). Studies on the structure and regeneration of some woody species indicated that there are species that require urgent conservation measures. Sound management and monitoring, as well as maintenance of biodiversity, cultural and ...

  19. Proceedings – Mathematical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Author Affiliations. A Carriazo1 L M Fernández1 A Rodríguez-Hidalgo1. Department of Geometry and Topology, Faculty of Mathematics, University of Sevilla, Apartado de Correos 1160, 41080-Sevilla, Spain ...

  20. Environmental Compliance Assessment System (ECAS). North Carolina Supplement

    Science.gov (United States)

    1994-09-01

    Ridley Turtle Lepidochelys kempii E Hawksbill Turtle Eretmochelys imbricala E Leatherback Turtle Dernwchelys coriacea T American Alligator Alligator...boschianum T Dwarf Filmy-fern Trichomanes petersii T Mottled Trillium Trillium discolor T Dwarf Bladderwort Utricularia olivacea E = Endangered T