632 research outputs found
Species of Bursaphelenchus Fuchs, 1937 (Nematoda: Parasitaphelenchidae) and other nematode genera associated with insects from Pinus pinaster in Portugal
Insects associated with maritime pine, Pinus pinaster, in Portugal were collected
and screened for the presence of Bursaphelenchus species. Nematodes were
identified using Internal Transcribed Spacers-Restriction Fragment Length
Polymorphism (ITS-RFLP) analysis of dauer juveniles and morphological
identification of adults that developed from dauer juveniles on fungal cultures
or on cultures in pine wood segments at 26 C. Several associations are
described: Bursaphelenchus teratospicularis and Bursaphelenchus sexdentati are
associated with Orthotomicus erosus; Bursaphelenchus tusciae, B. sexdentati and/or
Bursaphelenchus pinophilus with Hylurgus ligniperda and Bursaphelenchus hellenicus
with Tomicus piniperda, Ips sexdentatus and H. ligniperda. An unidentified
Bursaphelenchus species is vectored by Hylobius sp. The previously reported
association of Bursaphelenchus xylophilus with Monochamus galloprovincialis
was confirmed. The association of Bursaphelenchus leoni with Pityogenes sp. is
not definitively established and needs further studies for clarification.
Other nematode genera besides Bursaphelenchus were found to be associated
with the insects sampled, including two different species of Ektaphelenchus, Parasitorhabditis
sp., Parasitaphelenchus sp., Contortylenchus sp. and other unidentified
nematodes. The Ektaphelenchus species found in O. erosus is morphologically
similar to B. teratospicularis found in the same insect; adults of both the species
are found in cocoon-like structures under the elytra of the insects.
Introduction
Approximately one third of the nematodes belonging to
the order Aphelenchida Siddiqi, 1980 are associated with
insects (Poinar, 1983). These nematodes establish a variety
of associations with the insects, which may be
described as commensalism, e.g. phoresy (to the benefit
of the nematode but not affecting the insect), mutualism
(both the organisms benefit) or parasitism (nematodes
benefit at the expense of the insect) (Giblin-Davis,
2004).
Most Bursaphelenchus Fuchs, 1937 species are mycetophagous,
feeding on fungi in the galleries of bark beetles
and thu
Synthesis and Purification of Peptide Nucleic Acids
Peptide nucleic acids (PNAs) are DNA analogs in which the normal phosphodiester backbone is replaced by 2‐aminoethyl glycine linkages. Hybridization of PNAs with RNA or DNA follows normal rules for Watson‐Crick base pairing and occurs with high affinity. Thus, PNAs are a promising choice for applications that benefit from high‐affinity hybridization. They are assembled using techniques adapted from peptide chemistry. Protocols are given for both automated and manual synthesis of PNAs as well as their purification. The advantages of each method are discussed, as are the different monomers and reagents that are required. Additionally, protocols are given for adding peptides to PNAs (which can enhance hybridization or cell uptake of the PNA) and for adding a biotin label.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143745/1/cpnc0411.pd
Survey of the genus Bursaphelenchus Fuchs, 1937 (Nematoda: Aphelenchoididae) in Romania
An overview of the occurrence of species of the genus Bursaphelenchus in Romania is
presented. The data is based on recent surveys conducted for the first time throughout the
country, to monitor and evaluate the potential entry of the pine wood nematode,
Bursaphelenchus xylophilus. Wood samples were collected from declining trees, woodprocessing
companies and imported wood packaging material. Of the 895 wood samples
examined, 11 contained Bursaphelenchus specimens. Morphological and molecular analyses
were carried out to characterize the species detected. With respect to the possible presence
of B. xylophilus, all samples were negative, confirming the absence of this quarantine
pest in Romania. Nevertheless, five Bursaphelenchus species were found: B. hofmanni,
B. poligraphi, B. vallesianus, B. willibaldi, and one putative new species belonging to the
sexdentati group, classified here as Bursaphelenchus sp. NR512. These results constitute the
first report of the genus Bursaphelenchus in Romania
Cross-Modal Soundscape Mapping: Integrating Ambisonic Environmental Audio Recordings and High Dynamic Range Spherical Panoramic Photography
Presented at the 20th International Conference on Auditory Display (ICAD2014), June 22-25, 2014, New York, NY.We cannot “measure” the soundscape any more than we can “measure” the ocean, the city, or the wilderness. Being comprised of myriad complex elements, conditions and relationships between sound sources and sound perceivers, the soundscape—and any sufficient description of it—must account for several different, but significantly interrelated, dimensions: physical, spatial, temporal, perceptual, cultural, and historical. How, then, are we to meaningfully document the soundscape? If we are to begin to understand the soundscape’s impact on us—and our impact upon it—we need new methods to capture and represent the multisensory extents of a soundscape without reverting to one-dimensional quantitative abstractions. This project proposes an interdisciplinary method to record a soundscape’s multisensory attributes by combining aural and visual information in a structured way which links the directionality of view and sound arrival. This method integrates multi-directional Ambisonic audio recordings with high dynamic range (HDR) spherical panoramic photography in the form of interactive maps and virtual tours. Case studies using the cross-modal soundscape mapping method will be presented
Source localization in complex listening situations: Selection of binaural cues based on interaural coherence
Performance of ionospheric maps in support of long baseline GNSS kinematic positioning at low latitudes
Ionospheric scintillation occurs mainly at high and low latitude regions of the Earth and may impose serious degradation on GNSS (Global Navigation Satellite System) functionality. The Brazilian territory sits on one of the most affected areas of the globe, where the ionosphere behaves very unpredictably, with strong scintillation frequently occurring in the local postsunset hours. The correlation between scintillation occurrence and sharp variations in the ionospheric total electron content (TEC) in Brazil is demonstrated in Spogli et al. (2013). The compounded effect of these associated ionospheric disturbances on long baseline GNSS kinematic positioning is studied in this paper, in particular when ionospheric maps are used to aid the positioning solution. The experiments have been conducted using data from GNSS reference stations in Brazil. The use of a regional TEC map generated under the CALIBRA (Countering GNSS high-Accuracy applications Limitations due to Ionospheric disturbances in BRAzil) project, referred to as CALIBRA TEC map (CTM), was compared to the use of the Global Ionosphere Map (GIM), provided by the International GNSS Service (IGS). Results show that the use of the CTM greatly improves the kinematic positioning solution as compared with that using the GIM, especially under disturbed ionospheric conditions. Additionally, different hypotheses were tested regarding the precision of the TEC values obtained from ionospheric maps, and its effect on the long baseline kinematic solution evaluated. Finally, this study compares two interpolation methods for ionospheric maps, namely, the Inverse Distance Weight and the Natural Neighbor
Satellite DNA as a target for TaqMan real-time PCR detection of the pinewood nematode, Bursaphelenchus xylophilus
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