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A comparative ultrastructural study of pit membranes with plasmodesmata associated thickenings in four angiosperm species Naturalis
Rabaey, D.; Lens, F.; Huysmans, S.; Smets, E.; Jansen, S..
Recent micromorphological observations of angiosperm pit membranes have extended the number and range of taxa with pseudo-tori in tracheary elements. This study investigates at ultrastructural level (TEM) the development of pseudo-tori in the unrelated Malus yunnanensis, Ligustrum vulgare, Pittosporum tenuifolium, and Vaccinium myrtillus in order to determine whether these plasmodesmata associated thickenings have a similar developmental pattern across flowering plants. At early ontogenetic stages, the formation of a primary thickening was observed, resulting from swelling of the pit membrane in fibre-tracheids and vesselelements. Since plasmodesmata appear to be frequently, but not always, associated with these primary pit membrane thickenings, it remains...
Tipo: Article / Letter to the editor Palavras-chave: Ontogeny; Pseudo-torus; Tracheary element; Pit membrane; Bordered pit; Wood ultrastructure; 42.56.
Ano: 2008 URL: http://www.repository.naturalis.nl/record/430078
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A reevaluation of the evidence supporting an unorthodox hypothesis on the origin of extant amphibians Naturalis
Marjanovic, D.; Laurin, M..
The origin of frogs, salamanders and caecilians is controversial. McGowan published an original hypothesis on lissamphibian origins in 2002 (McGowan, 2002, Zoological Journal of the Linnean Society, 135: 1-32), stating that Gymnophiona was nested inside the 'microsaurian' lepospondyls, this clade was the sister-group of a caudate-salientian-albanerpetontid clade, and both were nested inside the dissorophoid temnospondyls. We have investigated McGowan's data matrix and isagree with the scoring of 35% of the cells. All taxa and all but two characters are affected. In some cases, we have a different interpretation about correspondence between morphology and character states, or we delimit states differently (or use information that was unknown in 2002). In...
Tipo: Article / Letter to the editor Palavras-chave: Albanerpetontidae; Brachydectes; Coding; Continuous characters; Data matrix; Gerobatrachus; Gymnophioniformes; Gymnophionomorpha; Lissamphibia; Lysorophia; Morphology; Ontogeny; Paleontology; Phylogeny; Scoring; Stepmatrix gap-weighting; 42.82.
Ano: 2008 URL: http://www.repository.naturalis.nl/record/289109
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A standardized description of European Sminthuridae (Collembola, Symphypleona), 3: description of seven species of Sminthurus, including four new to science Naturalis
Nayrolles, Pierre.
The following three species are redescribed: Sminthurus viridis (Linnaeus, 1758), Sminthurus nigromaculatus Tullberg, 1871, and Sminthurus multipunctatus Schäffer, 1896. Four new species are described from France and Spain: Sminthurus bourgeoisi n. sp., Sminthurus bozoulensis n. sp., Sminthurus leucomelanus n.sp.,and Sminthurus hispanicus n. sp. The importance of the ontogeny of chaetotaxy is stressed. Indeed, not all species acquire the secondary chaetotaxy in the same instar, and for these characters the most informative instar is not the adult but the third juvenile instar. The study of such characters involves the clustering of similar characters. A short discussion is given about this issue (selection of characters and clustering criteria).
Tipo: Article / Letter to the editor Palavras-chave: Collembola; Symphypleona; Sminthurus; Chaetotaxy; New species; Taxonomy; Ontogeny; France; Spain.
Ano: 1995 URL: http://www.repository.naturalis.nl/record/503948
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A SUBADULT MAXILLA OF A TYRANNOSAURIDAE FROM THE TWO MEDICINE FORMATION, MONTANA, UNITED STATES Pap. Avulsos de Zool. (São Paulo)
DELCOURT,RAFAEL.
ABSTRACT Daspletosaurus is a Campanian genus of Tyrannosauridae from North America. This genus occupied the same geographic area of Albertosaurus, but remains of Albertosaurus are more abundant than Daspletosaurus. Here is described a subadult maxilla (AMNH FARB 5477) of Daspletosaurus sp. from Montana (USA) and possibly from the Two Medicine Formation. The description is based on Carr (1999) that described cranial ontogenetic variations in tyrannosaurids. The maxilla belongs to the ontogenetic Stage 3 sensu Carr (1999), in which the maxilla is thick, the lateral surface of the bone well sculptured, and the maxillary fenestra is subcircular and well separated from the anterior edge of antorbital fossa. Possibly there were more than one species of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Daspletosaurus; Ontogeny; North America; Montana.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492017000900113
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Age and Sex-Related Geometrical Variation of Ramus mandibulae of Sus scrofa's (Mammalia: Artiodactyla) Jaws International Journal of Morphology
Hohl,Leandro dos S. L; Sicuro,Fernando L; Azorit,Concepción; Carrasco,Rafael; Rocha-Barbosa,Oscar.
Morphological variation of the ramus mandibulae of wild Sus scrofa was described and correlated to sex and age differences. Young forms (n=27, 15 males, 12 females) and adults (n=23, 13 males, 10 females) were analyzed through Geometric Morphometrics (2-D) to assess differences between groups. We found significant differences between age- and sex-related shape variations at ramus mandibulae level. Young wild boars present bulky angular process with backward oriented coronoid process, while adults show slender jaw vertical ramus, and orthogonally oriented coronoid process. The ramus mandibulae in female wild boars is more robust and bulky than in males. The morphological changes between young and adult forms are related to alterations in the osteo-muscular...
Tipo: Journal article Palavras-chave: Mandible; Ontogeny; Sexual Dimorphism; Wild boar.
Ano: 2014 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022014000400026
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Analysis of a species/instars/characters table: a theoretical survey on the use of chaetotaxy in ontophylogenetic studies Naturalis
Nayrolles, Pierre.
Phylogenetic studies on several groups of arthropods, such as Acari (mites) or Collembola (springtails), make wide use of chaetotaxy. Chaetotaxic characters, besides being morphological features (setal shape), often have a binary nature, that is presence vs. absence. A seta can be variable in a population, and one may attribute a presence probability to this seta. In fact, the presence probability should be defined for each instar. One might think that a variable seta corresponds to a polymorphism (e.g., two or more alleles in a population); in fact, setal variability should be regarded as the result of a propensity intrinsic to individuals, i.e., a potentiality being expressed at random among specimens. The phenomenon known as lateral inhibition explains...
Tipo: Article / Letter to the editor Palavras-chave: Ontogeny; Phytogeny; Chaetotaxy; Probabilistic organs; Ontogenetic trajectories; Arthropods; Collembola; Symphypleona.
Ano: 1998 URL: http://www.repository.naturalis.nl/record/534360
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Are the dinosauromorph femora from the Upper Triassic of Hayden Quarry (New Mexico) three stages in a growth series of a single taxon? Anais da ABC (AABC)
MÜLLER,RODRIGO T..
ABSTRACT The lagerpetid Dromomeron romeri and the theropod Tawa hallae are two dinosauromorphs from the Norian (Upper Triassic) of the Chinle Formation, situated in New Mexico, USA. However, a recent study suggests the inclusion of the holotype of D. romeri (GR 218) and paratype (GR 155) and referred (GR 235) specimens of T. hallae in an ontogenetic series of a single species. The specimens GR 218 and GR 155 include just an isolated femur, while GR235 includes femora, pelvis and tail. The inclusion of the specimens in an unique ontogenetic series relies on the putative immature condition and plastic deformation of the specimen GR 218. However, as observed here, the disparity between the femora of D. romeri and T. hallae is considerably higher than those...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chinle Formation; Dinosauria; Dinosauriformes; Lagerpetidae; Norian; Ontogeny.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000300835
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Beschreibung der sechs Nauplius-Stadien von Parastenocaris phyllura Kiefer, 1938 im Vergleich mit P. vicesima Klie, 1935 (Copepoda, Harpacticoida) Naturalis
Glatzel, Thomas.
Six non-overlapping size classes and morphologically distinct nauplius stages of Parastenocaris phyllura are studied using light microscopy. The nauplii have been reared in laboratory cultures. A comparative analysis of the morphology of the nauplius stages of P. phyllura and P. vicesima (cf. Schminke, 1982) is presented.
Tipo: Article / Letter to the editor Palavras-chave: Copepoda; Parastenocaris phyllura; Groundwater; Nauplius stages; Ontogeny.
Ano: 1992 URL: http://www.repository.naturalis.nl/record/504514
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Body condition influences ontogeny of foraging behavior in juvenile southern elephant seals ArchiMer
Orgeret, Florian; Cox, Samantha; Weimerskirch, Henri; Guinet, Christophe.
Ontogeny of diving and foraging behavior in marine top predators is poorly understood despite its importance in population recruitment. This lack of knowledge is partly due to the difficulties of monitoring juveniles in the wild, which is linked to high mortality early in life. Pinnipeds are good models for studying the development of foraging behaviors because juveniles are large enough to robustly carry tracking devices for many months. Moreover, parental assistance is absent after a juvenile departs for its first foraging trip, minimizing confounding effects of parental input on the development of foraging skills. In this study, we tracked 20 newly weaned juvenile southern elephant seals from Kerguelen Islands for up to 338 days during their first trip...
Tipo: Text Palavras-chave: Accelerometers; Diving behavior; Early-life; First-year juveniles; Foraging behavior; Ontogeny; Satellite relay tags; Southern elephant seals.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00482/59380/62484.pdf
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Characterization of the early development of Pseudoplatystoma reticulatum Eigenmann & Eigenmann, 1889 (Siluriformes: Pimelodidae) from the Paraguay River Basin Neotropical Ichthyology
Andrade,Fernanda F.; Lima,Ariane F.; Assumpção,Lucileine; Makrakis,Sergio; Kasai,Rodrigo I. D.; Makrakis,Maristela C..
ABSTRACT This study described the initial development of Pseudoplatystoma reticulatum, as well as changes in growth patterns. Morphometric and meristic variables were analyzed during embryonic, larval and juvenile periods, even as allometric growth coefficients for larvae and juveniles. Eggs showed an average diameter of 1.79 mm and broad perivitelline space (23.41%). The total length (TL) of the larvae ranged from 3.05 to 25.72 mm, and the total number of myomeres ranged from 45 to 50 (preanal = 13-16 and postanal = 30-35). Initial pigmentation is poor, concentrated at the extremities of the yolk sac. In the flexion stage, the pigmentation intensifies and forms a longitudinal stripe extending from the snout to the operculum and two longitudinal stripes on...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Allometric growth; Early life stages; Fish larvae; Morphology; Ontogeny.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000200216
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Chronotype ontogeny related to gender BJMBR
Duarte,L.L.; Menna-Barreto,L.; Miguel,M.A.L.; Louzada,F.; Araújo,J.; Alam,M.; Areas,R.; Pedrazzoli,M..
Chronotype is an established concept designed to identify distinct phase relationships between the expression of circadian rhythms and external synchronizers in humans. Although it has been widely accepted that chronotype is subjected to ontogenetic modulation, there is no consensus on the interaction between age and gender. This study aimed to determine the relationship between age- and gender-related changes in the morningness-eveningness character in a large sample of people. A total of 14,650 volunteers were asked to complete the Brazilian version of the Horne and Östberg chronotype questionnaire. The data demonstrated that, on average, women were more morning-oriented than men until the age of 30 and there were no significant differences between men...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chronotype; Gender; Ontogeny; Circadian rhythms; Sleep timing.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000400316
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Comments on Triassic pterosaurs with discussion about ontogeny and description of new taxa Anais da ABC (AABC)
Kellner,Alexander W.A..
Eudimorphodon ranzii was the first Triassic pterosaur to be described and several specimens have been referred to this taxon mainly based on the presence of multicuspid teeth. Since this dental feature has been observed in several other pterosaurs, the revision of some specimens assigned to Eudimorphodon shows that they represent new taxa as follows: Arcticodactyluscromptonellus (comb. nov.), Austriadraco dallavecchiai (gen. et sp. nov.) and Bergamodactyluswildi (gen. et sp. nov.). A preliminary analysis of pterosaur ontogeny resulted in the recognition of six distinct ontogenetic stages (OS1-6). According to this classification, the holotype of Arcticodactyluscromptonellus has reached OS2, and although being ontogenetically much younger than others, the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pterosauria; Ontogeny; Eudimorphodon; Arcticodactylus; Austriadraco; Bergamodactylus.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000200669
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Conservation status and bio-ecology of Brycon orbignyanus (Characiformes: Bryconidae), an endemic fish species from the Paraná River basin (Brazil) threatened with extinction Neotropical Ichthyology
Tonella,Lívia Helena; Dias,Rosa Maria; Vitorino Junior,Oscar Barroso; Fugi,Rosemara; Agostinho,Angelo Antonio.
ABSTRACT Brycon orbignyanus is an endemic species from La Plata basin whose stocks have been presenting significant reductions throughout the Paraná River. Brycon orbignyanus is categorized as an endangered species. This study evaluated aspects of the bio-ecology of this species that may be related to this threat, highlighting its distribution, abundance, and diet as well as the corresponding relationships between its recruitment and flood regimes. Data were obtained from different parts of the upper Paraná River (stretches free and regulated by dams) from 1986 to 2010 with more detailed data collected from the free remnant of this basin. The results indicate that no records for species exist at more than half of the sampling points located in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Dam; Diet; Floodplain; Ontogeny; Recruitment.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000300207
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Corallimorpharia collected during the CANCAP expeditions (1976-1986) in the south-eastern part of the North Atlantic* Naturalis
Hartog, J.C. den; Ocaña, O.; Brito, A..
Species of Corallimorpharia collected during the CANCAP expeditions in the south-eastern part of the North Atlantic are described and discussed, altogether five species belonging to three genera of Corallimorphidae: the shallow water forms Corynactis viridis Allman, 1846, Pseudocorynactis caribbeorum den Hartog, 1980, and P. caboverdensis spec. nov., and the deep-sea forms Corallimorphus cf. atlanticus Carlgren, 1934, and C. ingens Gravier, 1918. The taxonomic status of the representatives of the genus Corynactis Allman, 1846, is discussed. All temperate to subtropical species described so far belong to a group of closely related allopatric taxa forming the Corynactis viridis-complex, possibly representing a single species only. The colours of Corynactis...
Tipo: Article / Letter to the editor Palavras-chave: Corallimorpharia; Corallimorphidae; Corallimorphus; Corynactis; Pseudocorynactis; Sideractis; Nectactis; Nematocysts; Ontogeny; Distribution; Feeding; CANCAP-project; South-eastern North Atlantic; Macaronesia.; 42.72.
Ano: 1993 URL: http://www.repository.naturalis.nl/record/317646
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Corona development and floral nectaries of Asclepiadeae (Asclepiadoideae, Apocynaceae) Acta Botanica
Monteiro,Mariana Maciel; Demarco,Diego.
ABSTRACT Flowers of Asclepiadoideae are notable for possessing numerous nectaries and elaborate coronas, where nectar can accumulate but is not necessarily produced. Given the complexity and importance of these structures for reproduction, this study aimed to analyze the ontogeny of the corona, the structure and position of nectaries and the histochemistry of the nectar of species of Asclepiadeae. Two types of coronas were observed: androecial [C(is)] and corolline (Ca). The development of the C(is)-type of corona initiates opposite the stamens in all species examined with the exception of Matelea in which it begins to develop as a ring around the filament tube. Despite their morphological variation, coronas typically originate from the androecium. A...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Asclepiads; Histochemistry; Ontogeny; Nectar; Structural; Diversity.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000300420
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Desarrollo larval de merluza (Merluccius hubbsi) considerando aspectos ecomorfologicos OceanDocs
Betti, P..
The ontogeny of the first stages of development of hake (Merluccius hubbsi)considering yolksac larvae, preflexion larvae, larvae in flexion, postflexion larvae, transformation larvae and posttransition juveniles, is described. Fish larvae and posttransition juveniles were collected in the north Patagonian area, between 42° and 46°S, from surroundings of the coast to the 100 m isobath (Argentine Sea, SW Atlantic). The larvae were collected between December and February, and the posttransition juveniles, in April and June since 1989 to 2004. The morphometrics variables and pigmentation were recorded in 127 larvae y 41 posttransition juveniles ranging in total length (TL)from 2.0 to 35.0 mm. Additionally, the openning of the mouth was calculated and...
Tipo: Theses and Dissertations Palavras-chave: Fish larvae; Juveniles; Ontogeny; Morphogenesis; Morphogenesis; Fish larvae; Juveniles; Ontogeny; Http://aims.fao.org/aos/agrovoc/c_4943; Http://aims.fao.org/aos/agrovoc/c_2924; Http://aims.fao.org/aos/agrovoc/c_25393; Http://aims.fao.org/aos/agrovoc/c_12941.
Ano: 2005 URL: http://hdl.handle.net/1834/2599
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Description of Atherinella brasiliensis (Quoy & Gaimard, 1825) (Atheriniformes: Atherinopsidae) larvae from the Jaguaribe River estuary, Itamaracá island, Northeastern Brazil Neotropical Ichthyology
França,Elton J.; Severi,William; Castro,Maviael F.; Medeiros,Tatiane N.; El-Deir,Ana Carla A..
The present study describes the external morphology and morphometry of the initial development of Atherinella brasiliensis, and contributes toward broadening knowledge on its biology. A total of 88 larvae and 14 juveniles were used to characterize the morphological development and analyze body proportions. Fish with standard lengths (SL) from 1.4 to 77 mm were used in the study. Larvae hatch at an average of 1.4 mm SL. In the preflexion stage, the larval body is enveloped by a finfold, which begins behind the head. Pectoral fins are the first to be formed and preflexion larvae have four characteristic dendritic chromatophores on the head. The flexion stage begins at an average of 4.4 mm SL; dorsal and anal fins already exhibit pterygiophores and a...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Silverside; Larval development; Early juvenile; Ontogeny.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300016
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Desenvolvimento inicial de larvas de Rhaphiodon vulpinus Agassiz (Characiformes, Cynodontidae) Zoologia
Sousa,Wilson Treger Zydowicz de; Severi,William.
The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barão de Melgaço, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cynodontidae; Rhaphiodon vulpinus; Larval development; Ontogeny; Morphometrics.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752002000100006
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Development and some histochemical aspects of foliar glandular trichomes of Stevia rebaudiana (Bert.) Bert. - Asteraceae Rev. Bras. Bot.
MONTEIRO,WALKYRIA ROSSI; CASTRO,MARÍLIA DE MORAES; MAZZONI-VIVEIROS,SOLANGE CRISTINA; MAHLBERG,PAUL GORDON.
The ten-celled biseriate glandular trichome of Stevia rebaudiana (Bert.) Bert.-Asteraceae, found on both leaf surfaces, originates from a single protruding, protodermal cell undergoing an anticlinal division. A subsequent series of periclinal divisions, occurring in acropetal sequence, leads to the formation of the trichome, composed of five pairs of cells, one pair of basal cells, another of stalk cells and three pairs of secretory head cells. Developing, still two-celled glandular trichomes already occur on leaf primordia of the second pair (these primordia measuring, in some cases, ca. 0.30 mm in length), and most of the glandular trichomes are at the mature phase on very young, expanding leaves, for example on those of the sixth pair. The secretory...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Stevia rebaudiana; Asteraceae; Glandular trichomes; Ontogeny; Histochemistry.
Ano: 2001 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042001000300013
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Development, structure and distribution of colleters in Mandevilla illustris and M. velutina (Apocynaceae) Rev. Bras. Bot.
APPEZZATO-DA-GLÓRIA,BEATRIZ; ESTELITA,MARIA EMÍLIA MARANHÃO.
Colleters of Mandevilla illustris and M. velutina are present on the cotyledons, shoot apices, mature leaves and on the nodal region, where they are interpetiolar and intrapetiolar. In M. velutina there are two colleters on the adaxial basal part of the leaf blade, and in M. illustris, this number varies. The differentiation of the colleters occurs in the early stages of leaf development. When colleters are mature, they consist of a long head on a short stalk. The central core of the colleter is made up of parenchymatous cells that may exhibit phenolic compounds and is surrounded by radially elongated epithelial cells. The foliar and intrapetiolar colleters can exhibit vascularization. The colleters produce a translucient sticky substance that reacts...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Colleters; Mandevilla; Apocynaceae; Anatomy; Ontogeny.
Ano: 2000 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042000000200001
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