Search Results - (Author, Cooperation:M. Toledo)

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  1. 1
    H. ter Steege ; N. C. Pitman ; D. Sabatier ; C. Baraloto ; R. P. Salomao ; J. E. Guevara ; O. L. Phillips ; C. V. Castilho ; W. E. Magnusson ; J. F. Molino ; A. Monteagudo ; P. Nunez Vargas ; J. C. Montero ; T. R. Feldpausch ; E. N. Coronado ; T. J. Killeen ; B. Mostacedo ; R. Vasquez ; R. L. Assis ; J. Terborgh ; F. Wittmann ; A. Andrade ; W. F. Laurance ; S. G. Laurance ; B. S. Marimon ; B. H. Marimon, Jr. ; I. C. Guimaraes Vieira ; I. L. Amaral ; R. Brienen ; H. Castellanos ; D. Cardenas Lopez ; J. F. Duivenvoorden ; H. F. Mogollon ; F. D. Matos ; N. Davila ; R. Garcia-Villacorta ; P. R. Stevenson Diaz ; F. Costa ; T. Emilio ; C. Levis ; J. Schietti ; P. Souza ; A. Alonso ; F. Dallmeier ; A. J. Montoya ; M. T. Fernandez Piedade ; A. Araujo-Murakami ; L. Arroyo ; R. Gribel ; P. V. Fine ; C. A. Peres ; M. Toledo ; C. G. Aymard ; T. R. Baker ; C. Ceron ; J. Engel ; T. W. Henkel ; P. Maas ; P. Petronelli ; J. Stropp ; C. E. Zartman ; D. Daly ; D. Neill ; M. Silveira ; M. R. Paredes ; J. Chave ; A. Lima Filho Dde ; P. M. Jorgensen ; A. Fuentes ; J. Schongart ; F. Cornejo Valverde ; A. Di Fiore ; E. M. Jimenez ; M. C. Penuela Mora ; J. F. Phillips ; G. Rivas ; T. R. van Andel ; P. von Hildebrand ; B. Hoffman ; E. L. Zent ; Y. Malhi ; A. Prieto ; A. Rudas ; A. R. Ruschell ; N. Silva ; V. Vos ; S. Zent ; A. A. Oliveira ; A. C. Schutz ; T. Gonzales ; M. Trindade Nascimento ; H. Ramirez-Angulo ; R. Sierra ; M. Tirado ; M. N. Umana Medina ; G. van der Heijden ; C. I. Vela ; E. Vilanova Torre ; C. Vriesendorp ; O. Wang ; K. R. Young ; C. Baider ; H. Balslev ; C. Ferreira ; I. Mesones ; A. Torres-Lezama ; L. E. Urrego Giraldo ; R. Zagt ; M. N. Alexiades ; L. Hernandez ; I. Huamantupa-Chuquimaco ; W. Milliken ; W. Palacios Cuenca ; D. Pauletto ; E. Valderrama Sandoval ; L. Valenzuela Gamarra ; K. G. Dexter ; K. Feeley ; G. Lopez-Gonzalez ; M. R. Silman
    American Association for the Advancement of Science (AAAS)
    Published 2013
    Staff View
    Publication Date:
    2013-10-19
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    *Biodiversity ; Models, Biological ; Population ; *Rivers ; South America ; Trees/*classification/*physiology
    Published by:
    http://www.aaas.org/

    Latest Papers from Table of Contents or Articles in Press
  2. 2
    L. Poorter ; F. Bongers ; T. M. Aide ; A. M. Almeyda Zambrano ; P. Balvanera ; J. M. Becknell ; V. Boukili ; P. H. Brancalion ; E. N. Broadbent ; R. L. Chazdon ; D. Craven ; J. S. de Almeida-Cortez ; G. A. Cabral ; B. H. de Jong ; J. S. Denslow ; D. H. Dent ; S. J. DeWalt ; J. M. Dupuy ; S. M. Duran ; M. M. Espirito-Santo ; M. C. Fandino ; R. G. Cesar ; J. S. Hall ; J. L. Hernandez-Stefanoni ; C. C. Jakovac ; A. B. Junqueira ; D. Kennard ; S. G. Letcher ; J. C. Licona ; M. Lohbeck ; E. Marin-Spiotta ; M. Martinez-Ramos ; P. Massoca ; J. A. Meave ; R. Mesquita ; F. Mora ; R. Munoz ; R. Muscarella ; Y. R. Nunes ; S. Ochoa-Gaona ; A. A. de Oliveira ; E. Orihuela-Belmonte ; M. Pena-Claros ; E. A. Perez-Garcia ; D. Piotto ; J. S. Powers ; J. Rodriguez-Velazquez ; I. E. Romero-Perez ; J. Ruiz ; J. G. Saldarriaga ; A. Sanchez-Azofeifa ; N. B. Schwartz ; M. K. Steininger ; N. G. Swenson ; M. Toledo ; M. Uriarte ; M. van Breugel ; H. van der Wal ; M. D. Veloso ; H. F. Vester ; A. Vicentini ; I. C. Vieira ; T. V. Bentos ; G. B. Williamson ; D. M. Rozendaal
    Nature Publishing Group (NPG)
    Published 2016
    Staff View
    Publication Date:
    2016-02-04
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    *Biomass ; Carbon/metabolism ; Carbon Cycle ; Carbon Sequestration ; Ecology ; *Forests ; Humidity ; Latin America ; Rain ; Time Factors ; Trees/*growth & development/metabolism ; *Tropical Climate
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  3. 3
    R. J. Brienen ; O. L. Phillips ; T. R. Feldpausch ; E. Gloor ; T. R. Baker ; J. Lloyd ; G. Lopez-Gonzalez ; A. Monteagudo-Mendoza ; Y. Malhi ; S. L. Lewis ; R. Vasquez Martinez ; M. Alexiades ; E. Alvarez Davila ; P. Alvarez-Loayza ; A. Andrade ; L. E. Aragao ; A. Araujo-Murakami ; E. J. Arets ; L. Arroyo ; C. G. Aymard ; O. S. Banki ; C. Baraloto ; J. Barroso ; D. Bonal ; R. G. Boot ; J. L. Camargo ; C. V. Castilho ; V. Chama ; K. J. Chao ; J. Chave ; J. A. Comiskey ; F. Cornejo Valverde ; L. da Costa ; E. A. de Oliveira ; A. Di Fiore ; T. L. Erwin ; S. Fauset ; M. Forsthofer ; D. R. Galbraith ; E. S. Grahame ; N. Groot ; B. Herault ; N. Higuchi ; E. N. Honorio Coronado ; H. Keeling ; T. J. Killeen ; W. F. Laurance ; S. Laurance ; J. Licona ; W. E. Magnussen ; B. S. Marimon ; B. H. Marimon-Junior ; C. Mendoza ; D. A. Neill ; E. M. Nogueira ; P. Nunez ; N. C. Pallqui Camacho ; A. Parada ; G. Pardo-Molina ; J. Peacock ; M. Pena-Claros ; G. C. Pickavance ; N. C. Pitman ; L. Poorter ; A. Prieto ; C. A. Quesada ; F. Ramirez ; H. Ramirez-Angulo ; Z. Restrepo ; A. Roopsind ; A. Rudas ; R. P. Salomao ; M. Schwarz ; N. Silva ; J. E. Silva-Espejo ; M. Silveira ; J. Stropp ; J. Talbot ; H. ter Steege ; J. Teran-Aguilar ; J. Terborgh ; R. Thomas-Caesar ; M. Toledo ; M. Torello-Raventos ; R. K. Umetsu ; G. M. van der Heijden ; P. van der Hout ; I. C. Guimaraes Vieira ; S. A. Vieira ; E. Vilanova ; V. A. Vos ; R. J. Zagt
    Nature Publishing Group (NPG)
    Published 2015
    Staff View
    Publication Date:
    2015-03-20
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Atmosphere/chemistry ; Biomass ; Brazil ; Carbon/analysis/metabolism ; Carbon Dioxide/*analysis/metabolism ; *Carbon Sequestration ; Plant Stems/metabolism ; *Rainforest ; Trees/growth & development/metabolism ; Tropical Climate ; Wood/analysis
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  4. 4
    TOLEDO, M. C. F. ; REYES, F. G. R. ; IADEROZA, M. ; FRANCIS, F. J. ; DRAETTA, I. S.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1983
    Staff View
    ISSN:
    1750-3841
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Process Engineering, Biotechnology, Nutrition Technology
    Notes:
    Anil trepador (Cissus sicyoides, Linn) is a tropical tree of the Vitacea family. The pigments in the fruits were extracted and identified by conventional chromatographic, spectral and chemical methods. The pigments, in order of prominence, were delphinidin-3-rutinoside, cyanidin-3-rhamnosyl-arabinoside and delphinidin-3-rhamnoside. Another pigment was present in amounts too low for conventional identification. The anthocyanin content of the fruit juice was 119.4 mg/100 mL. The fruit of this plant may have potential as a food colorant.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1365-2621.1983.tb09238.x

    Articles: DFG German National Licenses
  5. 5
    Nicieza, A. G. ; Braña, F. ; Toledo, M. M.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1991
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    Growth dynamics of juvenile Atlantic salmon, Salmo salar L., from two sections of the Narcea River and one of the Esva River (Northern Spain) were examined in relation to the development of bimodality in their size–frequency distributions. Size–bimodality was clearer under intermediate growth (section A) than under relatively fast or slow growth. The proportion of fish entering the upper modal group increase with growth intensity. Composition of upper and lower modal groups became fixed prior to December, and at this time both groups separated on the 90–95 mm interval. Fish exhibiting smolt appearance in late March (larger than 130 mm) had already been upper group fish in December, while parr-like fish and those that remained in the river by May (potential 2-year-old smolts) had formed the lower modal group. Anadromous salmon catch in the Narcea River was mostly of previously 1-year-old smolts (97.6%), of which 94% were larger than 100 mm by their first winter. In the Esva River, slow growth of juveniles is consistent with a large proportion of 2-year-old smolts (47.9%) among anadromous salmon. Both juvenile samples and scale analysis of anadromous salmon indicate that 2-year-old smolts were larger than 1-year-olds. Early disappearance of the former (before March) is, at least, partially related to earlier migration of large fish, since sexual maturity of parr does not provide a complete explanation. The Narcea stock have a minimum length at smolting of about 130 mm and an optimum smolt size in the 155–175 mm interval. Mean smolt length did not vary although the winter length changed between years.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1095-8649.1991.tb03138.x

    Articles: DFG German National Licenses
  6. 6
    Rivero, J. L. L. ; Diz, A. ; Toledo, M. ; Aguera, E.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1994
    Staff View
    ISSN:
    1439-0264
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Notes:
    The histochemical characteristics of skeletal muscle were assessed using a range of samples from 7 appendicular muscles taken from adult mixed-breed dogs (1.5 to 3 years of age). Two slow-twitch fiber subtypes (IA and IB) and three II subtypes (IIA, IIB and IIC) were identified according to myofibrillar myosin adenosine triphosphatase reaction after acid and alkaline preincubation. Type IIB fibers were not found in all muscles, and were only biologically significant in m. semiten-dinosus. The metabolic potential of these fibers is fairly similar to that of IIA fibers, but significantly different to that of IIB fibers in other mammals, suggesting that they may be designed to play a different functional role during locomotion. All canine muscle fibers have moderate to high oxidative capacity, which may be related to the extraordinary athletic capability of the species.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1439-0264.1994.tb00482.x

    Articles: DFG German National Licenses
  7. 7
    Staff View
    ISSN:
    1438-1168
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Geosciences
    Description / Table of Contents:
    Zusammenfassung Die geochemischen Charakteristika von frühkretazischen Karbonatitproben aus Ostparaguay (Rio Alpa, Amambay und Zentrale Provinzen) wurden untersucht. Die Daten belegen, daß alle Vorkommen eine isotopische Anreicherungssignatur zeigen und daß ihnen eine entsprechende Krustensignatur fehlt. Ein Petrologisches Modell (Ausgangsschmelze, fraktionierte Kristallisation, hydrothermale Interaktion und Verwitterung) wird auf Grund der Verteilung der inkompatiblen Spurenelemente, der stabilen (C-O) und radiogenen (Sr-Nd) Isotope vorgeschlagen. Es versucht die Bedeutung der Karbonatitkomplexe als „Markerhorizonte” des metasomatischen subkontinentalen Mantels zu überprüfen. Die Ergebnisse zeigen, daß die Karbonatite und die primären Karbonate in Ostparaguay, und jene aus dem Paraná Becken SüdostBrasiliens durch zeitlich und zusammensetzungsmäßig unterschiedliche metasomatische Prozesse erfaßt wurden.
    Notes:
    Summary Geochemical characteristics were systematically determined for Early Cretaceous samples of carbonatitic rocks from Eastern Paraguay (Rio Apa, Amambay and Central Provinces). The data show that all the occurrences have an enriched isotopic signature and that the carbonatites have negligible or absent crustal signature. A petrogenetic model (parent liquids, fractional crystallization, hydrothermal interactions and weathering) is proposed as a function of incompatible trace element, stable (O-C) and radiogenic (Sr-Nd) isotope variations with the aim to test the significance of carbonatitic complexes as a marker of the metasomatized subcontinental lithospheric mantle. The results indicate that the carbonatites and primary carbonates from eastern Paraguay, and those from the north eastern Paraná Basin (SE Brazil), were affected by metasomatic events distinct in time and composition.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF01172487

    Articles: DFG German National Licenses
  8. 8
    Staff View
    ISSN:
    1438-2199
    Keywords:
    Amino acids ; Lysine ; Herbicides ; Azotobacter ; Xenobiotics
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Notes:
    Summary Production of lysine byAzotobacter chroococcum strain H23 was studied in chemically-defined media amended with different concentrations of alachlor, metolachlor, 2,4-D, 2,4,5-T and 2,3,6-TBA. The presence of 5, 10, and 50μg/ml of alachlor or 2,3,6-TBA significantly decreased quantitative production of lysine. However, the presence 2,4-D or 2,4,5-T at concentrations of 10 and 50μg/ml enhanced the production of lysine. Quantitative production of lysine was not affected as consequence of the addition of metolachlor to the culture medium, showing that the release lysine to the culture media byA. chroococcum was not affected by that herbicide.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF01361879

    Articles: DFG German National Licenses
  9. 9
    Staff View
    ISSN:
    1432-0789
    Keywords:
    A. chroococcum ; Seed inoculation ; Zea mays ; Acetylene reduction assay ; Yield response ; Associative N2 fixation
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Geosciences
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Summary Inoculated and non-inoculated seedlings of Zea mays were grown in agricultural soils under aseptic and non-sterile conditions. Acetylene reduction activity and microbial counts were determined after 7 and 30 days of growth. Irrespective of the soil type Azotobacter spp. were commonly isolated under maize cultivation. Inoculation of agricultural soils with a suspension of A. chroococcum led to an increase in Azotobacter numbers, although this effect diminished with time. Nitrogenase activity was detected on maize roots and increased in response to the inoculation with A. chroococcum, showing that this associative growth could be of primary importance for the plant. The results of assays for acetylene reduction activity indicated that the nitrogenase activity was associated only with the root systems.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00257669

    Articles: DFG German National Licenses
  10. 10
    Staff View
    ISSN:
    1432-0789
    Keywords:
    A. chroococcum ; Zea mays ; Yield response ; Fertilizer N ; Inoculation
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Geosciences
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Summary Field experiments were conducted during 1985 and 1986 to examine the effect of Azotobacter chroococcum on the grain yield of maize. Application of 40 kg N ha−1 plus A. chroococcum caused a significant increase in maize yield. Azotobacter inoculation was more efficient at lower doses (40 kg N ha−1) than at high doses (80 kg N ha−1) of urea.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00261026

    Articles: DFG German National Licenses
  11. 11
    Staff View
    ISSN:
    1432-0789
    Keywords:
    Key words Azotobacter ; Azospirillum ; Rhizobium ; Vicia faba L. ; Legume inoculation
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Geosciences
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Abstract  Mixed inoculation of Vicia faba L. with four different Rhizobium/Azospirillum and Rhizobium/Azotobacter combinations led to changes in total content, concentration and/or distribution of the mineral macro- and micronutrients, K, P, Ca, Mg, Fe, B, Mn, Zn and Cu, when compared with plants inoculated with Rhizobium only. The effects varied to a great extent among the Azotobacter and Azospirillum strains selected for combined inoculation.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s003740050540

    Articles: DFG German National Licenses
  12. 12
    TEROL TOLEDO, M.

    Pamplona : Periodicals Archive Online (PAO)
    Published 1987
    Staff View
    ISSN:
    0021-325X
    Topics:
    Law
    Theology and Religious Studies
    Notes:
    CUESTIONES SOBRE EL PROCESO DE NULIDAD DEL MATRIMONIO
    URL:
    http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:p022-1987-027-53-000006

    Articles: DFG German National Licenses
  13. 13
    Staff View
    ISSN:
    1432-0789
    Keywords:
    Methidathion ; Soil microflora ; Enumeration of functional bacterial groups ; Acetylene reduction assay ; ARA
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Geosciences
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Summary We studied the effects of the organophosphorus insecticide methidathion, at concentrations of 10, 50, 100, 200 and 300 μg g-1 in an agricultural soil, on fungi, total bacterial populations, aerobic N2-fixing bacteria, denitrifying bacteria, nitrifying bacteria (phases I and II), and nitrogenase activity (acetylene reduction assay). The presence of 10–300 μg g-1 of methidathion significantly increased fungal populations (colony-forming units). Denitrifying bacteria, aerobic N2-fixing bacteria and N2 fixation were significantly increased at concentrations of 50–300 μg g-1. The total number of bacteria increased significantly at concentrations of 100–300 μg g-1. Nitrifying bacteria decreased initially at concentrations of 300 μg g-1, but recovered rapidly to levels similar to those in the control soil without the insecticide.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00336275

    Articles: DFG German National Licenses
  14. 14
    Staff View
    ISSN:
    1432-072X
    Keywords:
    Azotobacter ; Low-phosphate medium-Adenine nucleotides ; Energy charge-Poly ; β-hydroxybutyrate
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Notes:
    Abstract The effect of a low phosphate concentration on intracellular adenine nucleotide content, oxygen consumption and poly-β-hydroxybutyrate deposition was investigated with N-free and NH 4 + batch cultures of Azotobacter vinelandii. When the microorganisms were cultured under low-phosphate concentrations the cells contained much larger amounts of poly-β-hydroxybutyrate, but displayed lower oxygen consumption activities and energy charge values than did control cells. Also, the ratio ATP to ADP was much higher in control cells and the intracellular levels of ATP were lower in low-phosphate cells.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00406132

    Articles: DFG German National Licenses
  15. 15
    Staff View
    ISSN:
    1432-072X
    Keywords:
    Azotobacter vinelandii ; Phenolic acids ; Nitrogenase activity
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Notes:
    Abstract Growth and nitrogenase activity (acetylene reduction) of Azotobacter vinelandii in chemically defined N-free media were studied in the presence of p-hydroxybenzoic, vanillic, p-coumaric, and ferulic acids at concentrations from 0.01 to 1% (w/v). Growth and nitrogenase activity were only detected when the microorganism was cultured on p-hydroxybenzoic acid either as sole carbon source or mixed with other phenolic acids, suggesting that p-hydroxybenzoic acid could be utilized as a carbon source by A. vinelandii for growing under certain environmental conditions.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00425149

    Articles: DFG German National Licenses
  16. 16
    Staff View
    ISSN:
    1438-2199
    Keywords:
    Amino acids ; Azotobacter ; Azospirillum ; Biotechnology
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Notes:
    Summary Interest of microbial production of amino acids has been increased greatly since development of biotechnological methods. These methods represent a perspective way applied in a future large-scale manufacture of inexpensive amino acids. In this context, the isolation of producing organisms that may be exploited in the desing of alternative methods for the production of amino acids could be of primary importance. In this review we will describe the liberation of amino acids (methionine, lysine, arginine, tryptophane and glutamic acid) byAzotobacter andAzospirillum during growth in culture media with different carbon sources under diazotrophic and adiazotrophic conditions. These organisms may be useful in developing new methods for the industrial production of amino acids.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00806540

    Articles: DFG German National Licenses
  17. 17
    Staff View
    ISSN:
    1573-4838
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Technology
    Notes:
    Abstract A previously developed method to improve the interface between hydroxyapatite (HA) and a polyester-ether (PolyactiveTM 70/30) by using polyacrylic acid or poly(ethylene-co-maleic acid) has been applied to HA/PolyactiveTM 30/70 composites noting that polyactiveTM 30/70 contains less polyethylene glycol (PEG) segments and a higher concentration of rigid poly(butylene terephthalate) (PBT) segments. The mobility of the PEG segments is significantly affected by the existence of a high concentration of rigid PBT segments. Our experimental results show that this method is indeed suitable for making HA/PolyactiveTM 30/70 composites. The hydrogen bond/dipole interaction forming ability of the PEG segment is not affected by the existence of relatively large amounts of PBT segments. By using these coupling agents, the mechanical properties of the composite can be significantly improved both in dry and wet states. A fractographical study of the fracture surfaces revealed that the surface modified HA particles maintain better contact at fracture. It also showed that larger HA particles may initiate cracks and that such particles may be responsible for a decrease in the tensile strength of the composites.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1023/A:1008826410395

    Articles: DFG German National Licenses
  18. 18
    Staff View
    ISSN:
    1573-3017
    Keywords:
    Alachlor ; herbicides ; pesticides ; soil bacteria ; enzymatic activities
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Energy, Environment Protection, Nuclear Power Engineering
    Notes:
    A study was made of the effects of one selected acetanilide herbicide, alachlor, at concentrations of 2.0–10.0 kg ha−1 on bacterial populations, fungi, dinitrogen fixation bacteria, denitrifying bacteria, nitrifying bacteria, nitrogenase activity, acid and alkaline phosphatases, arylsulfatase and deshydrogenase. The presence of 2.0–10.0 kg ha−1 of alachlor in the soil increased the total number of bacteria and fungi. The population of denitrifying bacteria increased significantly at concentrations of 5.0–10.0 kg ha−1. However, aerobic dinitrogen fixing bacteria and nitrogenase activity decreased at alachlor concentrations of 3.5–10.0 kg ha−1. Acid and alkaline phosphatases, arylsulfatase and dehydrogenase activity decreased significantly initially at concentrations of 5.0–10.0 kg ha−1, but recovered to levels similar to those in the control. Nitrifying bacteria were not affected as a consequence of the addition of the herbicide to agricultural soil.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00121384

    Articles: DFG German National Licenses
  19. 19
    Staff View
    ISSN:
    1573-5117
    Keywords:
    community structure ; species diversity ; elevation ; stream order ; diadromous fishes ; unpassable dams
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Notes:
    Abstract Relationships between the fish community and selected habitat features were examined in a set of short temperate streams located at the northern end of the Iberian Peninsula. The fish fauna in these streams consists mostly of diadromous or estuarine species. Species richness and diversity increased with stream order, depth and width and decreased with elevation and distance from the sea. Stream order (positively) and elevation (negatively) were the two variables most highly correlated with species richness and diversity; higher order streams (order 3–4) showed greater values of species diversity than lower order ones (order 1) even when the elevation effect was removed. Addition of species in the downstream direction, but no replacement or loss was evidenced. We also compared the observed values of species diversity with those predicted from habitat features for a set of locations above unpassable dams. A great majority of the sites showed lower than predicted diversity values, which is an expected outcome for this mainly migratory fish fauna.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00023171

    Articles: DFG German National Licenses
  20. 20
    Staff View
    ISSN:
    1573-5036
    Keywords:
    chlorpyrifos ; insecticides ; methylpyrimifos ; organophosphorus ; soil microflora
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Abstract A study of the effects of two selected organophosphorus insecticides methylpyrimifos and chlorpyrifos on soil microflora in an agricultural loam was made. The insecticides had concentrations of 10 to 300 μg g−1. The presence of methylpyrimifos at concentrations of 100 to 300 μg g−1 or chlorpyrifos at concentrations from 10 to 300 μg g−1 significantly decreased aerobic dinitrogen fixing bacteria and dinitrogen fixation. Nitrifying bacteria decreased at concentrations of 200 and 300 μg g−1 of methylpyrimifos. The presence of 10 to 300 μg g−1 of chlorpyrifos decreased the total number of bacteria. However, fungal populations and denitrifying bacteria were not affected as a consequence of the addition of the organophosphorus insecticides to the agricultural soil, showing that these microorganisms can tolerate high amounts of those insecticides.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00009367

    Articles: DFG German National Licenses