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1.
The objective of this project was to study the pollen spectrum of the Marahué Wildlife Reserve (Central Argentina), the quantity and quality of airborne pollen grains, and to evaluate the contribution of outside sources, to protect a natural habitat with xerophytic shrub vegetation (“monte”) (the term “monte” is used for the dominant xerophytic shrub vegetation in the “partido” of Villarino) approximately 90 km south of Bahía Blanca. Sampling was performed weekly throughout a whole calendar year (January–December, 2003) using a volumetric impact sampler. Observations of flowering in the field were performed at the same time as the aerial sampling. Herbarium specimens were collected to make pollen collections of the species found in the study area, for reference purposes. The most abundant pollen types were Poaceae (31.3% total annual pollen), Amaranthus/Chenopodiaceae (25.3%), Eucalyptus (5%), Brassicaceae (3.9%), and Plantago (3.9%). This study showed the dispersion dynamics of pollen grains from characteristic species of the “partido” (the province of Buenos Aires is divided into partidos which are roughly equivalent to counties) of Villarino, the exotic flora of the surrounding area, and the pollen types from outside the region.
María Gabriela MurrayEmail:
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2.
The sexual pattern and sexual development of the leopard grouper, Mycteroperca rosacea, were investigated from 483 specimens collected from the Gulf of California, Mexico. Histological and population data indicated a gonochoric sexual pattern. Some juveniles passed through an immature bisexual phase of gonadal development, but no evidence of post-maturational sex change was found. The immature bisexual phase is believed to be associated only with male development. The size distribution and size at sexual maturity were similar for both males and females. In accordance with predictions of the size-advantage model, the gonochoric sexual pattern of M. rosacea is likely influenced by its group-spawning mating system.
Brad E. ErismanEmail:
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3.
Mycena aphanes and Mycena exilis, belonging to section Filipedes and section Polyadelphia, are proposed as new species. They are described and illustrated and compared to other species in the two sections. Mycena aphanes is a strikingly characteristic Mycena with fulvous or yellowish brown colours of both pileus and stipe. Mycena exilis is characterized by its occurrence on fallen Salix leaves, a pale brown pileus, occasionally with a pale pink tinge, narrowly adnate lamellae, four-spored basidia, and the presence of clamp connections.
Gro GuldenEmail:
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4.
We compared the infectivity of two nucleopolyhedroviruses (NPVs), MyseNPV G isolated from Mythimna separata (Walker) (Lepidoptera: Noctuidae) and SpltNPV S isolated from Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae). MyseNPV G was more pathogenic against M. separata than against S. litura. Although SpltNPV S was more pathogenic than MyseNPV G against S. litura, it did not infect M. separata. Restriction endonuclease (REN) analysis of viral genomic DNA revealed that the two NPVs have quite different REN profiles. Based on nucleotide sequences of the coding regions of polyhedrin, lef-8 and lef-9, SpltNPV S was closely related to other SpltNPV isolates, whereas MyseNPV G appeared to belong to the Mamestra NPV group, and was distinct from a Chinese isolate of Leucania (=Mythimna) separata NPV. The potential of MyseNPV G and SpltNPV S to control pest insects is discussed.
Katsuo Tsuda (Corresponding author)Email:
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5.
6.
Detailed analysis of Darwin’s scientific notes and other writings from the Beagle voyage reveals a focus on endemism and replacement of allied taxa in time and in space that began early in the journey. Though it is impossible to determine exactly when Darwin became a transmutationist, the evidence suggests that he was conversant with the transmutational ideas of Lamarck and others and testing (“experimenting” with) them—before he received a copy of Lyell’s Principles of Geology, vol. 2, in November 1832, in which Lyell describes and disputes Lamarck’s theory. To the two rhea species of Patagonia and the four mockingbird species of the Galapagos, we can now add the living Patagonian cavy (rodent) species, and its extinct putatively related species that Darwin collected at Monte Hermoso (Bahia Blanca) in the Fall of 1832, as a replacement pattern absolutely critical to the development of Darwin’s transmutational thinking. Darwin developed his first transmutational theory by adopting “Brocchi’s analogy” (Rudwick 2008)—i.e. that births and deaths of species are analogous to the births and deaths of individuals. Births and deaths of species, as of individuals, are thus explicable in terms of natural causes. Darwin explored these themes and the replacement of the extinct cavy by the modern species explicitly in his February 1835 essay (Darwin 1835a).
Niles EldredgeEmail:
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7.
A blue protein present in the mucus coating blue forms of walleye, Sander vitreus, was purified to homogeneity by a combination of ion exchange and hydrophobic interaction chromatography. The purified protein has a molecular mass of 87,850 and is a homotetramer with a subunit molecular mass of 21,836. Solutions of the protein are deep blue in color and show absorbance maxima at 383 and 633 nm, respectively. Acetone treatment of the protein releases a blue chromophore with the spectral characteristics of biliverdin IXα. The results suggest that the blue protein is a new biliprotein that we have termed Sandercyanin. The function of Sandercyanin is unknown, but limited amino acid sequence analysis suggests it is a lipocalin that may be involved in the transport of heme degradation products.
David T. GibsonEmail:
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8.
We examined the influence of crop management (crop density, nitrogen fertilization level) and landscape parameters [areal proportion of oilseed rape (OSR), Brassica napus L. var. oleifera Metzg. (Brassicaceae), and proportions, lengths and distances of various non-crop habitats] on the parasitism of stem weevils (Ceutorhynchus spp.; Coleoptera: Curculionidae) and pollen beetles (Meligethes spp.; Coleoptera: Nitidulidae) by parasitic wasps (Hymenoptera: Ichneumonidae). Larvae of host insects were sampled in 29 winter OSR fields located in landscapes ranging from structurally simple to complex. Spatial scales of landscape effects were considered at eight radii (250–2,000 m) centered in the studied OSR fields. Stem weevil parasitism was unaffected by crop management variables but negatively related to roadside strip length at radius 250 m and grassy fallow area at a radius of 500 m. Pollen beetle parasitism was positively related to the crop density and to lengths of roadside strips and hedges within a radius of 250 m. Thousand kernel mass of OSR was positively related to pollen beetle parasitism but unrelated to stem weevil parasitism.
Johann G. ZallerEmail:
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9.
The interconnection network is one of the key architectural components in any parallel computer. The distribution of the traffic injected into the network is among the factors that greatly influences network performance. The uniform traffic pattern has been adopted in many existing network performance evaluation studies due to the tractability of the resulting analytical modelling approach. However, many real applications exhibit non-uniform traffic patterns such as hot-spot traffic. K-ary n-cubes have been the mostly widely used in the implementation of practical parallel systems. Extensive research studies have been conducted on the performance modelling and evaluation of these networks. Nonetheless, most of these studies have been confined to uniform traffic distributions and have been based on software simulation. The present paper proposes a new stochastic model to predict message latency in k-ary n-cubes with deterministic routing in the presence of hot-spot traffic. The model has been validated through simulation experiments and has shown a close agreement with simulation results.
Geyong MinEmail:
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10.
In 2001 Carijoa riisei, an octocoral native to the tropical Western Atlantic, was discovered overgrowing black corals in the Au’au Channel in Hawaii. In this paper data from a 2001 survey are reanalyzed and combined with new data from 2003 and 2004 to assess the ecological impact in greater detail. C. riisei differentially affected reproductively mature black coral colonies with maximum impact between 80 and 105 m. The pattern of C. riisei overgrowth on black corals and C. riisei on the substrata appears to be bounded by high irradiance in shallow water and cold temperature in deep water. Evidence suggests that the C. riisei settlement on black corals is facilitated by other epifauna. Once established, C. riisei spreads vegetatively and smothers the coral. The success of the C. riisei invasion appears to be unaided by anthropogenic disturbance and is at least partially attributable to Hawaii’s depauperate shallow-water (<100 m) octocoral fauna.
Richard W. GriggEmail:
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11.
We tested the pathogenicity of 18 Metarhizium anisopliae (Metschn.) Sorokin isolates and 22 Beauveria bassiana (Balsamo) Vuillemin isolates against Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) larvae and adults. The efficacy of the most virulent isolate—M. anisopliae K—was evaluated in containers with a concrete bottom covered with wood shavings, under simulated poultry house conditions. Application of conidia of this isolate to the shavings or directly to the concrete bottom reduced the yield of larvae in 8–15 time compared with the control. In another test, the mortality of mature larvae placed on previously inoculated shavings or bottom reached 80–90% within 14 days, compared with 14% in the control. The residual activity of conidia kept at 28°C retained its initial level during 14 days post-inoculation, but declined after three weeks. Based on our data M. anisopliae has considerable potential for the control of A. diaperinus.
Michael SamishEmail: Email:
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12.
Competition for pollination is thought to be an important factor structuring flowering in many plant communities, particularly among plant taxa with morphologically similar and easily accessible flowers. We examined the potential for heterospecific pollen transfer (HPT) in a community of four Acacia species in a highly seasonal tropical habitat in Mexico. Partitioning of pollen flow among sympatric species appears to be achieved, in part, through segregation of flowering in seasonal time, and interspecific differences in pollinator guilds. However, two coflowering species (Acacia macracantha and Acacia angustissima) shared multiple flower visitors, raising the possibility of HPT. Each of these coflowering species showed high intraspecific daily synchrony in pollen release, but dehisce at different times of day. Pollinators rapidly harvested available pollen from one species before abandoning it to visit the flowers of the second later in the day. The activity of shared pollinators, predominantly bees, is thus structured throughout the day, and potential for HPT reduced. Suggestive evidence in favour of a resource partitioning explanation for this pattern is provided by the fact that A. macracantha showed significantly greater intraspecific synchrony when coflowering with a potential competitor (A. angustissima) than when flowering alone. We discuss our results in light of previous work on coflowering acacia assemblages in Tanzania and Australia. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Nigel E. RaineEmail:
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13.
14.
The Small Red Damselfly (Ceriagrion tenellum) (De Villiers) (Odonata: Coenagrionidae: Ceriagrion) is classed as vulnerable (Shirt, British Red Data Book, Nature Conservancy Council, Peterborough, UK, 1987) throughout the UK, and is included in certain Local Biodiversity Action Plans (LBAPs) in the south. A large proportion of any Biodiversity Action Plan is concerned with the requirement of conservation and management programmes. In order to guide them, information about the habitat preferences of the species concerned is vital. Detailed habitat information was collected to include a variety of physical parameters particularly vegetation, both in-channel and bankside. The species was found to be primarily associated with in-channel emergent broad-leaved plants, bankside grasses and rushes, and shallow, narrow channels with dark organic substrate. The consequences of these findings are discussed in relation to the conservation and management of C. tenellum.
Alison M. StrangeEmail:
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15.
16.
Predictive performance modelling of parallel component compositions   总被引:1,自引:0,他引:1  
Large-scale scientific computing applications frequently make use of closely-coupled distributed parallel components. The performance of such applications is therefore dependent on the component parts and their interaction at run-time. This paper describes a methodology for predictive performance modelling and evaluation of parallel applications composed of multiple interacting components. In this paper, the fundamental steps and required operations involved in the modelling and evaluation process are identified—including component decomposition, component model combination, M×N communication modelling, dataflow analysis and overall performance evaluation. A case study is presented to illustrate the modelling process and the methodology is verified through experimental analysis.
Stephen A. JarvisEmail:
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17.
The presence of several types of allelochemicals has been reported from Ajuga, a Labiatae genus comprising more than 40 species of wide distribution in extratropical regions of both hemispheres. The genus is of great medicinal and economic importance and among the biological properties of the secondary metabolites, the antifeedant activity against pest insects appears to be related to the presence of neo-clerodane type diterpenes. This review focuses on the isolation and structural elucidation of this type of compounds from Ajuga species and the hemisynthetic compounds of closely related structure obtained. The reported biological activity of crude extracts and isolated diterpenes will be briefly commented.
Josep CollEmail:
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18.
We surveyed slender lorises (Loris lydekkerianus) in Karnataka, south India intermittently during November 2001–July 2004 and estimated their relative abundance via direct sightings. Two subspecies, Loris lydekkerianus lydekkerianus and L. l. malabaricus, with different morphological traits, occur in the eastern drier region and the western wet region of the state, respectively. The distribution of Loris lydekkerianus lydekkerianus is patchy in a small region in the southeast, which contradicts earlier reports of its abundance throughout the state. Loris lydekkerianus malabaricus occurs throughout the Western Ghats as a contiguous population. The encounter rates of Loris lydekkerianus lydekkerianus and L. l. malabaricus are 0.41 individuals/km and 0.21 individuals/km, respectively. Whereas several forest tracts in the distributional range of Loris lydekkerianus malabaricus are protected areas, no such area exists in the distributional range of L. l. lydekkerianus. Loris lydekkerianus faces serious challenges of conservation because it largely occurs in commercial plantations, which can be relatively unstable habitats as harvesting can take place at any time.
Mewa SinghEmail:
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19.
20.
We propose a new retina simulation software, called Virtual Retina, which transforms a video into spike trains. Our goal is twofold: Allow large scale simulations (up to 100,000 neurons) in reasonable processing times and keep a strong biological plausibility, taking into account implementation constraints. The underlying model includes a linear model of filtering in the Outer Plexiform Layer, a shunting feedback at the level of bipolar cells accounting for rapid contrast gain control, and a spike generation process modeling ganglion cells. We prove the pertinence of our software by reproducing several experimental measurements from single ganglion cells such as cat X and Y cells. This software will be an evolutionary tool for neuroscientists that need realistic large-scale input spike trains in subsequent treatments, and for educational purposes.
Pierre Kornprobst (Corresponding author)Email:
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