249 resultados para CLIBANARIUS-VITTATUS BOSC


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Spermatozoa of most crustacean species are nonmotile and are packed into spermatophores. In Decapoda, spermatophores are highly variable in morphology and can be useful in the solving of taxonomic and systematic questions, especially among the Anomura. In this study, the morphology and morphometry of the spermatophores of the western Atlantic hermit crabs Pagurus brevidactylus and P criniticornis are described. The abdomen of fresh male specimens was dissected to expose the reproductive system and to extract the spermatophores, which were analyzed by stereoscopic, light, and scanning electron microscopy. The vas deferens can be divided macroscopically in three regions, all of them containing spermatophores. Tripartite spermatophores are composed of an elongated cylindrical main ampulla, a triangular accessory ampulla, a narrow cylindrical peduncle, and a round pedestal. Dimensions of the spermatophore components are positively correlated to the size of the crab. Morphological patterns observed in this study resemble those of other pagurid hermit crabs investigated to date. The morphological character distribution confirms classifications based on adult morphology and molecular analysis. J. Morphol. 272:1271-1280, 2011. (C) 2011 Wiley-Liss, Inc.

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The spermatophore morphology of the hermit crab Isocheles sawayai from Southwestern Atlantic (Brazil) is described. The spermatophores show similarities with those described for other members of the family Diogenidae, especially with the recently described Loxopagurus loxochelis. The spermatophore is composed of three major regions: a sperm filled head or ampulla, a columnar stalk and a foot or pedestal. The spermatophores show specific morphology in having a circular ampulla, and a constriction or neck between the ampulla (100 mu m) and the thin (27 mu m), long stalk (500 mu m). The stalk penetrates less than half way into the spermatophore head. Most spermatophores show one or the small posterior projections on the underside of the ampulla as being bigger than the other, making it asymmetrical. The size of the spermatophore is related to hermit crab size with direct relationships found between spermatophore ampulla width, total length, and peduncle length with shield length of the hermit crab. The morphological characteristics of the spermatophore of L sawayai. are species-specific distinguishing it from other members of the family, and are useful to infer further phylogenetic relationships. (C) 2008 Elsevier GmbH. All rights reserved.

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Introduction We studied the richness and abundance of ant species, their bacteria and the bacteria isolated from patient clinical samples. Methods Ants were collected with baited traps at 64 sites in a public hospital in São Luis, State of Maranhão, Brazil. Results In total, 1,659 ants from 14 species were captured. The most frequent species were Crematogaster victima, Solenopsis saevissima, Tapinoma melanocephalum, Camponotus vittatus and Paratrechina fulva. Forty-one species of bacteria were isolated from the ants and 18 from patients. Conclusions Ants are potential vehicles for pathogenic and opportunistic bacteria, and they can represent a risk factor in nosocomial infections.

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RESUMOComo parte dos estudos ambientais que foram desenvolvidos pelo INPA, de 1980 a 1986, em convênio com a ELETRONORTE, na área de influência da UHE Tucuruí. são redescritas e ilustradas 20 espécies da damília Anostomidae do baixo rio Tocantins, entre Cametá e Itupiranga, PA: Leporinus affins, L. tigrinus, L. desmotes, L. sp. 4, L. trifasciatus, L. friderici, L. sp. 1, L. sp. 2, L. sp. 3, L. granti, L. pachiycheilus, Laemolyta petiti, L. taeniata, Anostomoides laticeps, A. sp. 1, Anostomus ternetzi, Leporellus vittatus, Schizodon vittatus, Sartor tucuruiense e Abramites hypselenotus. Cinco espécies (Laemolyta petiti, Leporinus affinis, L. sp. 2, Anostomoides sp. 1 e Sartor tucuruiense) somente foram assiladas até agora para a bacia do Tocantins-Araguaia. Por outro lado, outras espécies anostomídeos, melhor representadas na bacia Amazônica, não foram encontrados no baixo Tocantins, fazendo supor que esta área, do ponto de vista ictiológico, está relativamente iosolado do restante da bacia Amazônica e possui um certo grau de endemismo. A maioria das espécies ocorre amplamente no baixo Tocantins, sendo que algumas apresentam acentuada preferência por determinados biótopos, como por exemplo Leporinus pachycheilus, L. desmotes, L. sp. 1 e Sartor tucuruiense, por corredeiras; Leporinus sp. 3, Anostomus ternetzi, por igarapés; Schizodon vittatus e Laemolyta taeniata,por zonas marginais, periodicametne alagáveis. A partir da análise dos caracteres merísticas e morfométricas, sobretudo o número, a forma e disposição dos dentes, posição da boca e número de escamas, a apresentada uma chave de identificação para as espécies estudadas.

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Abstract Background: Pulmonary hypertension is associated with poor prognosis in heart failure. However, non-invasive diagnosis is still challenging in clinical practice. Objective: We sought to assess the prognostic utility of non-invasive estimation of pulmonary vascular resistances (PVR) by cardiovascular magnetic resonance to predict adverse cardiovascular outcomes in heart failure with reduced ejection fraction (HFrEF). Methods: Prospective registry of patients with left ventricular ejection fraction (LVEF) < 40% and recently admitted for decompensated heart failure during three years. PVRwere calculated based on right ventricular ejection fraction and average velocity of the pulmonary artery estimated during cardiac magnetic resonance. Readmission for heart failure and all-cause mortality were considered as adverse events at follow-up. Results: 105 patients (average LVEF 26.0 ±7.7%, ischemic etiology 43%) were included. Patients with adverse events at long-term follow-up had higher values of PVR (6.93 ± 1.9 vs. 4.6 ± 1.7estimated Wood Units (eWu), p < 0.001). In multivariate Cox regression analysis, PVR ≥ 5 eWu(cutoff value according to ROC curve) was independently associated with increased risk of adverse events at 9 months follow-up (HR2.98; 95% CI 1.12-7.88; p < 0.03). Conclusions: In patients with HFrEF, the presence of PVR ≥ 5.0 Wu is associated with significantly worse clinical outcome at follow-up. Non-invasive estimation of PVR by cardiac magnetic resonance might be useful for risk stratification in HFrEF, irrespective of etiology, presence of late gadolinium enhancement or LVEF.

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Na região estuarina da Lagoa dos Patos, o siri-azul Callinectes sapidus Rathbun, 1869 é o mais abundante dentre as espécies do gênero. Apesar do siri-azul exercer influência sobre as comunidades bentônicas, por ser considerado um predador do topo da cadeia alimentar, não existem muitos estudos sobre aspectos ecológicos, inclusive sobre a composição e variabilidade sazonal de sua dieta natural, neste estuário. O objetivo principal deste estudo foi investigar a composição da dieta do siri-azul, evidenciando possíveis relações com a comunidade bentônica da região estuarina da Lagoa dos Patos. O período de estudo foi de março de 2003 a março de 2004, com coletas bimestrais. Os organismos foram coletados com auxílio de rede de arrasto de fundo, com malha de 13 mm entre nós opostos. Ainda em campo os animais foram fixados em formol 10%. Após a coleta os animais foram separados quanto ao sexo, medidos (largura e comprimento da carapaça - cm) e pesados (peso - g). Após a triagem, os animais foram dissecados e os intestinos retirados e pesados. As análises dos conteúdos alimentares dos siris demonstraram que os hábitos alimentares são diversificados, constituindo-se principalmente de invertebrados bentônicos. O item encontrado com maior freqüência foi Detrito, seguido pelo molusco filtrador Erodona mactroides Bosc, 1802 (Erodonidae). Crustáceos da classe Ostracoda e grãos de areia foram importantes componentes dos conteúdos dos intestinos anteriores, sendo que areia não foi considerada como item alimentar, propriamente dito. Também foram encontradas cerdas e mandíbulas de poliquetos, além de sementes das macrófitas Ruppia maritima L. (Potamogatonaceae) e Zannichellia palustris L. (Potamogatonaceae). Este estudo serve como subsídio para medidas de proteção e conservação da população do siri-azul, bem como caracteriza relações tróficas com comunidades bentônicas do estuário da Lagoa dos Patos.

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The aim of this study is to analyze and relate the spatial-temporal variability of macrozoobenthic assemblages to bottom characteristics and salinity fluctuations, in an estuarine shallow water region of Patos Lagoon. Monthly samples, between September 2002 and August 2003, were taken on six sampling stations (distant 90 m). Three biological samples with a 10 cm diameter corer, one sample for sediment analysis, fortnightly bottom topography measurements, and daily data of temperature and salinity were taken from each station. Two biotic and environmental conditions were identified: the first corresponding to spring and summer months, with low macrozoobenthos densities, low values of salinity, small variations in bottom topographic level and weak hydrodynamic activity. A second situation occurred in the months of fall and winter, which showed increased salinity, hydrodynamics and macrobenthos organisms. These results which contrast with previous studies carried out in the area, were attributed to failure in macrozoobenthos recruitments during summer period, especially of the bivalve Erodona mactroides Bosc, 1802 and the tanaid Kalliapseuses schubartii Mañe-Garzón, 1949. This results showed that recruitments of dominant species were influenced by salinity and hydrodynamic conditions.

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Uma análise cladística do relacionamento entre as espécies sul-americanas do grupo Sitalces (Sitalces Stål, 1878, Eusitalces Bruner, 1911, Parasitalces Bruner, 1911, Psilocirtus Bruner, 1911, Liebermannacris Costa & Carvalho, 2006, Robustusacris Costa & Carvalho, 2006, Arimacris Costa & Carvalho, 2006, Salvadoracris Costa & Carvalho, 2006 e Caruaruacris Costa & Carvalho, 2006) é apresentada. A análise incluiu 14 espécies com três grupos-externos e 34 caracteres morfológicos. A monofilia do grupo é suportada por três sinapomorfias com índices de consistência e retenção de 100%: prozona maior que a metazona, borda posterior do pronoto não angulada e placa supranal mais curta em relação aos cercos. A análise resultou em um único cladograma: (P. olivaceus (E. vittatus (L. dorsualis; L. punctifrons) (R. balzapambae (A. trinitatis (S. nigritus; C. bivittatus) (S. volxemi (P. vulneratus; P. sexnotata)))))). Comentários biogeográficos são apresentados e relacionados com padrões pré-estabelecidos.

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The author studied, the horizontal and vertical distribution of most common part of the flora and fauna of the bay of Guanabara at Rio de Janeiro. In this paper the eulittoral, poly, meso and oligohaline regions were localised and studied; and the first chart of its distribution was presented (fig. 2). The salinity of superficial waters was established through determinations based on 30 trips inside the buy for collecting biological materials. Some often 409 determinations which were previous reported together with the present ones served for the eleboration of a salinity map of the bay of Guanabara (fig. 1). This map of fig. 2 shows the geographic locations of the water regions. EULITTORAL WATER REGIME — Fig. 3 shows the diagram scheme of fauna and flora of this regime. Sea water salinity 34/1.000, density mean 1.027, transparent greenish waters, sea coast with moderate bursting waves. Limpid sea shore with white sand, gneiss with the big barnacle Tetraclita squamosa var. stalactifera (Lam. Pilsbry. Vertical distributions: barna¬cles layers with a green region in which are present the oyster Ostrea pa-rasitica L., the barnacles Tetraclita, Chthamalus, Balanus tintinnabulum var. tintinnabulum (L.) e var. antillensis Pilsbry in connection with several mollusca and the sea beatle Isopoda Lygia sp. Covered by water and exposed to air by the tidal ritms, there is a stratum of brown animals that is the layer of mussels Mytilus perna L., with others brown and chestnut animals : the Crustacea Pachygrapsus, the little crab Porcellana sp., the stone crab Me-nippe nodifrons Stimpson, the sea stars Echinaster brasiliensis (Mull. & Tr.), Astropecten sp. and the sea anemones Actinia sp. Underneath and never visible there is a subtidal region with green tubular algae of genus Codium and amidst its bunches the sea urchin Lycthchinus variegatus (Agass.) walks and more deeply there are numerous sand-dollars Encope emarginata (Leske). The microplancton of this regime is Ceratiumplancton. POLYHALINE WATER REGIMB — Water almost sea water, but directly influenced by continental lands, with rock salts dissolved and in suspension. Salinity: 33 to 32/1.000. This waters endure the actions of the popular nicknamed «water of the hill» (as the waters of mesohaline and oligohaline regimes), becoming suddenly reddish during several hours. That pheno¬menon returns several times in the year and come with great mortality of fishes. In these waters, according to Dr. J. G. FARIA there are species of Protozoa : Peridinea, the Glenoidinium trochoideum St., followed by its satellites which he thinks that they are able to secret toxical substances which can slaughter some species of fishes. In these «waters of the hill» was found a species of Copepoda the Charlesia darwini. In August 1946 the west shore of the Guanabara was plenty of killed fishes occupying a area of 8 feet large by 3 nautical miles of lenght. The enclosure for catching fishes in the rivers mouthes presents in these periods mass dead fishes. The phenomenon of «waters of the hill» appears with the first rains after a period of long dryness. MESOHALINE WATER REGIME — Fig. 4 shows the the diagramm scheme. Salt or brackish water from 30 to 17/1.000 salinity, sometimes until 10/1.000. Turbid waters with mud in suspension, chestnut, claveyous waters; shore dirty black mud without waving bursting; the waters are warmer and shorner than those of the polihaline regime. Mangrove shore with the mangrove trees : Rhizophora mangle L., Avicennia sp., Laguncularia sp., and the »cotton tree of sea» Hibiscus sp. Fauna: the great land crab «guaimú» Cardisoma guanhumi Latr., ashore in dry firm land. There is the real land crab Ucides cordatus (L.) in wetting mud and in neigh¬ bourhood of the burrows of the fiddler-crabs of genus Uca. On stones and in the roots of the Rhizophora inhabits the brightly colored mangrove-tree-crab («aratu» Portuguese nickname) Goniopsis cruentata (Latreille) and the sparingly the big oyster Ostrea rhizophorae Guild. Lower is the region of barnacles Balanus amphitrite var. communis Darwin and var. niveus Darwin; Balanus tintinnabulum var. tintinnabulum (L.) doesn't grow in this brackish water; lower is the region of Pelecipoda with prepollency of Venus and Cytherea shell-fishes and the Panopeus mud crab; there are the sea lettuce Ulva and the Gastreropod Cerithium. The Paguridae Clibanarius which lives in the empty shells of Gasteropod molluscs, and the sessile ascidians Tethium plicatum (Lesuer) appears in some seasons. In the bottom there is a black argillous mud where the «one landed shrimps» Alpheus sp. is hidden. OLIGOHALINE WATER REGIME — The salinity is lower than 10/1.000. average 8/1.000. There are no barnacles and no sea-beetles Isopods of genus Lygia; on the hay of the shore there are several graminea. This brackish water pervades by mouthes of rivers and penetrates until about 3 kilometers river above. While there is some salt dissolved in water, there are some mud crabs of the genus Uca, Sesarma, Metasesarma and Chasmagnatus. The presence of floating green plants coming from the rivers in the waters of a region indicated the oligohaline waters, with low salt content because when the average of NaCl increases above 8/1.000 these plants die and become rusty colored.

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Estudi realitzat a partir d’una estada al laboratori del Dr. Maurizio Mencuccini a la School of GeoSciences de la University of Edinburgh, entre els mesos d’agost i desembre del 2006. El treball realitzat s’ha centrat en tres projectes. Primerament, s’ha desenvolupat un sensor per mesurar el flux de saba al xilema i al floema, basat en la utilització de polsos de calor per tal d’estimar la velocitat del flux de massa en un medi porós. A diferència del mètode que es fa servir normalment per estimar el flux al xilema, s’ha aconseguit un nou mètode que assoleix l’escalfament fent servir un làser, la qual cosa fa que el mètode sigui no intrusiu. Per altra banda, s’ha estudiat la variabilitat de l’anatomia del floema en funció de l’edat de l’arbre en poblacions de tres espècies diferents (Pinus sylvestris, Fraxinus excelsior i Acer pseudoplatanus). L’objectiu de l’estudi és veure si l’edat/mida dels arbres afecta la mida dels elements conductors al floema, la superfície de floema funcional, o la relació entre superfície de floema funcional i superfície de fulles. Finalment, s’ha estudiat l’intercanvi de gasos a nivell de branca en funció de l’edat de l’arbre i la posició a la capçada en un bosc de Pinus sylvestris.

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Estudi arqueològic integrat de la vall del Madriu-Perafita-Claror (Andorra) iniciat al 2004 sota la coordinació de l’ICAC. L’estudi s’insereix en la declaració de la vall com a Patrimoni de la Humanitat (UNESCO). Las recerques s’enfoquen des de l’Arqueologia del Paisatge, de manera diacrònica i pluridisciplinar, fent especial atenció a les relacions de les societats amb el medi. Les restes arqueològiques treballades s’associen a activitats ramaderes, metal•lúrgiques i de carboneig. La recerca paleoecològica se centra en sediments lacustres, torbosos i arqueològics. L’any 2006, s’han analitzat a alta resolució temporal dues seqüencies palinològiques: l’estany Blau (2471 m) i la torbera de Bosc dels Estanyons (2180 m), obtenint les principals fases d’explotació i antropització d’aquest espai altimontà, així com l’evolució del paisatge en els darrers 11000 anys . La campanya de camp s’ha centrat en l’obtenció de mostres de pluja pol•línica referencial a la vall i en el sondatge de l’estany Forcat (2539 m). Un total de tres mostres han estat enviades a datar per C14. Els treballs arqueològics s’han centrat en l’excavació de sondejos de diagnòstic als jaciments de Basses de Setut (2325 m) i Pleta de les Bacives ( 2530 m) i en la realització de prospeccions a les capçaleres de les valls de Madriu, Perafita i Claror. S’han documentat estructures arqueològiques i s’han realitzat estudis antracològics dels sediments excavats en aquestes. S’ha realitzat un transecte altitudinal de carboneres al llarg de la vall per tal de enregistrar una major diversitat cronològica dels espais de carboneig. S’han enviat datacions C14 per tal de determinar la cronologia de les estructures. Les datacions del 2005 mostren una intensa ocupació ramadera i de carboneig a partir del segle XIV, en època baixmedieval i moderna, així com un establiment metal·lúrgic d’època romana.

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Se realiza una diagnosis socioambiental y un presupuesto para el Plan de Manejo del Parque Nacional Los Quetzales (PNLQ). El PNLQ ocupa una superficie de 4117 ha. Presenta un régimen hí­drico elevado favorecido por la topografí­a quebrada que permite la presencia de fajas de condensación. Estas condiciones favorecen la presencia del bosque nublado que como se ha observado es el hábitat de innumerables especies, algunas de las cuales presentan gran valor ecológico. El presupuesto para el Plan de Manejo refleja cómo los gastos superan en una proporción importante a los ingresos, por lo que se recomienda centrar los esfuerzos en la búsqueda de formas de financiación (pago por servicios ambientales, convenios, co-manejo y donaciones). También se hace precisa una aportación anual del Gobierno Central para la ejecución del Plan.

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Les invasions biològiques representen una greu amenaça per al funcionament dels ecosistemes i per a la preservació de la biodiversitat.. La formiga argentina (Linepithema humile) està considerada com una de les 100 espècies invasores més nocives. Prospera en extenses àrees de clima mediterrani de regions temperades i subtropicals de tots els continents amb l’excepció de l’Antàrtida. És una formiga dominant i una competidora agressiva que mitjançant múltiples mecanismes, des de predació directe a competència, produeix efectes negatius en una amplia varietat de taxons, principalment formigues i altres artròpodes, però també vertebrats. S’ha investigat, per primera vegada, els efectes de la formiga invasiva sobre les comunitats d’artròpodes de fullatge i com aquestes pertorbacions es transmeten en la xarxa tròfica del bosc esclerofil•le mediterrani. En les suredes estudiades la invasió de formiga argentina és causa directe de la extinció local de la gran majoria de poblacions de formigues natives. En el període mostrejat s’han constatat també impactes negatius en la diversitat i en l’abundància d’artròpodes natius en les capçades dels arbres, particularment d’erugues. Una avaluació preliminar basada únicament amb dades del 2005 indica que, reduint la disponibilitat d’erugues, la formiga argentina empobreix l’hàbitat reproductiu de la mallerenga blava (Parus caeruleus). La mallerenga blava basa la dieta insectívora estricte de la seva pollada fonamentalment en les erugues. No hem detectat impactes en l’èxit reproductiu de les mallerengues blaves en zones envaïdes. Els polls crescuts en àrees envaïdes assoleixen una condició física similar als de les zones no envaïdes, però la reducció en la disponibilitat d’erugues associada a la invasió de formiga argentina es tradueix en un creixement descompassat i en una menor mida estructural del polls volanders. Així, les pertorbacions en la comunitat d’artròpodes associades a la invasió de la formiga argentina promouen efectes bottom-up que acaben perjudicant el desenvolupament dels polls de mallerenga blava.

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En aquest informe, fem una primera avaluació d'un sistema basat en un mini-UAV, operat per l'empresa CATUAV (www.catuav.com), sobre una zona a l'est del Parc Natural del Montseny (PNM) tot comparant amb imatges adquirides l'any anterior sobre la mateixa zona, amb sistemes i plataformes aèries de primer nivell per l'Institut Cartogràfic de Catalunya i que utilitzem com a referent de qualitat. Tot assumint que les imatges produïdes pels UAV són d'una qualitat inferior als sistemes convencionals de teledetecció aerotransportada, si la qualitat i operativitat són encara suficients, aquests sistemes, donat el seu cost, poden constituir una eina important per adquirir informació d'alta resolució pel control de l'evolució de camps abandonats, de l'estat de la vegetació de ribera, de l'estat fitosanitari de cobertes forestals i plagues, de la distribució d'espècies invasores, de les conseqüències d'actuacions de restauració o aclariment del bosc, de l'impacte dels visitants etc. En concret, en aquest informe avaluem el sistema de CATUAV pel que fa a: 1) Operativitat del vol i adquisició de les imatges sobre una zona prèviament assenyalada com objectiu; 2) Operativitat del producte en quant a la localització i orientació de les imatges sobre el terreny; i 3) Qualitat radiomètrica i geomètrica de les imatges.