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1.
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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2.
Bitter lupins (Lupinus spp.) are not used as a protein source because of their toxicity. However, they may have alternative uses as potential sources of natural insecticides. Quinolizidine alkaloids (QA) of three Mexican Lupinus species (Fabaceae): L. montanus (HBK), L. stipulatus (Agardh) and L. aschenbornii (Schauer), were analyzed by capillary Gas Chromatography-Mass Spectrometry. Sparteine was found in high amounts in both L. montanus and L. aschenbornii while the major alkaloids in L. stipulatus extract were aphylline and an epiaphylline-like compound. Alkaloid extracts were tested for their insecticidal activity using larvae of the Fall Armyworm, Spodoptera frugiperda (Smith); (Lepidoptera, Noctuidae) as a model pest. We compared LD50 values and mean weight of caterpillars fed with alkaloid extracts of the three species studied with those of sparteine, a widespread QA found in various lupin species. Extracts of L. montanus and L. aschenbornii were found to be as effective as sparteine and extracts L. stipulatus were found to be the most toxic against the larvae of S. frugiperda. This suggests that the various QA act differently on caterpillars, and could be used to control Spodoptera populations.
Kalina Bermúdez-TorresEmail:
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3.
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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4.
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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5.
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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6.
The insect-pathogenic fungus Ophiocordyceps sinensis (better known as Cordyceps sinensis) is harvested over much of the Himalayan plateau as a highly prized remedy in traditional Oriental medicine. Over the past 10 years its financial value has increased dramatically, with collectors paid as much as US $12,500 kg−1 for top-quality material. This is causing significant distortion to local economies, and there is widespread concern that the current rate of collection is unsustainable. This paper introduces the fungus and its insect hosts, documents some of the biological and social constraints to achieving sustainability, describes the socioeconomic climate within which harvest and sale occurs in Bhutan, and details the measures put in place by the Royal Government of Bhutan to promote wise management of this valuable natural resource.
Paul F. CannonEmail:
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Selected intrinsic aspects of the mode of action of 3-N-morpholinosydnonimine (SIN-1) and its follow-up products are investigated by means of density functional theory. Besides the well known radical-cationic Feelisch–Schoenafinger pathway, an alternative anionic route via a neutral radical is proposed and included in the study. The individual reaction pathways are followed. Most notably, the overall activation barrier for the cationic route is calculated to be 184.04 kcal mol–1, while the one for the anionic route is predicted to be more favorable with 14.09 kcal mol–1.Figure A mere conformational change is predicted by DFT theory to elicit NO ejection from the SIN-1a radical cation, formed after one electron oxidation of the N-nitrosohydrazine SIN-1a.
Roy U. Rojas WahlEmail: Phone: +1-201-836-1714
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The reaction of N-demethylation plays an important role in the degradation of some alkaloids in a number of organisms. This review presents how our understanding of the N-demethylation of nicotine in plants has been improved through studies in cell cultures of Nicotiana plumbaginifolia and N. glutinosa using a variety of isotopic techniques. The overall aim is to understand how metabolism recycles the alkaloid skeleton, both in terms of the metabolic route(s) exploited and the reaction mechanisms of the enzymes involved. The former has been approached using high-resolution 2-dimensional NMR and GC-MS methods; the latter by determining kinetic isotope effects and modelling the potential reaction steps. It appears that the mechanism for nicotine demethylation in plants is similar to but has significant differences from that described for mammals and Pseudomonas bacteria. These differences are discussed.
Richard J. RobinsEmail:
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This paper reports results from monitoring atmospheric pollen in Salitral de la Vidriera, an area of natural vegetation near Bahía Blanca city (East Central Argentina). Sampling was carried out weekly during January to December 2003 and May 2005 to April 2006 using a volumetric impact sampler. Observations of flowering in the field were carried out at the same time as the aerial sampling. During this period, 43 pollen types were identified; most of these correspond to pollen grains from either herbaceous or shrubby vegetation typical of the study area, for example Amaranthus, Brassicaceae, Centaurea, Poaceae, Chenopodiaceae, Urticaceae, some Asteraceae, and Condalia microphylla. This study on the atmosphere of Salitral de la Vidriera allowed us to identify the components of the vegetation type dominant in the area, namely a shrubby halophytic steppe. A well represented family, for example Chenopodiaceae, could, under appropriate weather conditions, be an important contributor of pollen to Bahía Blanca.
María Gabriela MurrayEmail:
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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.
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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18.
Sub-Antarctic Marion Island has had a permanent research station for 50 years and the islands Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by a human on foot were recorded. Three response variables were calculated: intensity of vocal reaction (IVR), intensity of non-vocal reaction (INR) and overall response index (ORI). At 5 m from the nest, twice as many birds stood and/or vocalised as at 15 m. Nearest neighbour distance, age and gender did not explain individual variability of responses. Study colony birds had higher IVR scores than non-study colony birds; birds at colonies closest to the station had the highest ORI scores. A better breeding record was associated with lower IVR and ORI scores, but a causative relationship remains to be demonstrated. A minimum viewing distance of 25 m is recommended for breeding Wandering Albatrosses.
Marienne S. de VilliersEmail: Fax: +27-21-6503434
John CooperEmail:
Peter G. RyanEmail:
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19.
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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20.
Bursicon was identified in 1965 as a peptide neurohormone that initiates the tanning of the insect cuticle immediately after the shedding of the old one during the final stages of the molting process. Its molecular identity as an approximately 30 kDa bioactive heterodimer consisting of two cystine knot proteins resisted elucidation for 43 years. The sequence of the two bursicon subunits is highly conserved among arthropods, and this conservation extends even to echinoderms. We review the efforts leading to bursicon’s characterization, the identification of its leucine-rich repeat-containing, G protein-coupled receptor (LGR2), and the progress towards revealing its various functions. It is now clear that bursicon regulates different aspects of wing inflation in Drosophila melanogaster besides being involved at various points in the cuticle tanning process in different insects. We also describe the current knowledge of the expression of bursicon in the central nervous system of different insects in large homologous neurosecretory cells, and the changes in its expression during the development of Manduca sexta and D. melanogaster. Although much remains to be learned, the elucidation of its molecular identity and that of its receptor has provided the breakthrough needed for investigating the diverse actions of this critical insect neurohormone.
Hans-Willi HoneggerEmail:
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