110 research outputs found
Ecology and Management of \u3ci\u3ePemphigus betae\u3c/i\u3e (Hemiptera: Aphididae) in Sugar Beet
Pemphigus betae Doane (Hemiptera: Aphididae), is a sporadic pest of sugar beet (Beta vulgaris L. var. vulgaris) in all major sugar beet production regions of North America. These oval-shaped, pale-yellowish insects, with a body length ranging from 1.9–2.4mm, secrete a waxy material, giving their subterranean colonies a moldy appearance. Poplars in the genus Populus L. are the preferred primary hosts, while sugar beet and certain weed species, such as common lambsquarters (Chenopodium album L.) and kochia (Kochia scoparia (L.)), are among the secondary hosts. Pemphigus betae has a complex and varied life cycle and is usually heteroecious and holocyclic, although anholocyclic apterae are known to overwinter in the soil. Heavy infestations of this aphid can induce significant reductions in yield, sugar content, and recoverable sugar. Under conditions of extreme stress and heavy infestations, the alienicolae can induce stunting, chlorosis, wilting, and even death of sugar beet plants. Accurately establishing population densities for sugarbeet root aphids presents a challenge, because the economic important stage of this insect is subterranean. However, use of a fall root rating index aids in estimating relative population densities. Furthermore, root aphids are especially difficult to control by means of conventional insecticides. For this reason, integrated pest management tactics, including the use of host plant resistance, cultural control techniques, and the use of natural enemies, should take precedence
Ecology and Management of Pemphigus betae (Hemiptera: Aphididae) in Sugar Beet
Published ArticlePemphigus betae Doane (Hemiptera: Aphididae), is a sporadic pest of sugar beet (Beta vulgaris L. var. vulgaris)
in all major sugar beet production regions of North America. These oval-shaped, pale-yellowish insects, with a
body length ranging from 1.9–2.4mm, secrete a waxy material, giving their subterranean colonies a moldy appearance.
Poplars in the genus Populus L. are the preferred primary hosts, while sugar beet and certain weed
species, such as common lambsquarters (Chenopodium album L.) and kochia (Kochia scoparia (L.)), are among
the secondary hosts. Pemphigus betae has a complex and varied life cycle and is usually heteroecious and holocyclic,
although anholocyclic apterae are known to overwinter in the soil. Heavy infestations of this aphid can induce
significant reductions in yield, sugar content, and recoverable sugar. Under conditions of extreme stress
and heavy infestations, the alienicolae can induce stunting, chlorosis, wilting, and even death of sugar beet
plants. Accurately establishing population densities for sugarbeet root aphids presents a challenge, because
the economic important stage of this insect is subterranean. However, use of a fall root rating index aids in estimating
relative population densities. Furthermore, root aphids are especially difficult to control by means of
conventional insecticides. For this reason, integrated pest management tactics, including the use of host plant
resistance, cultural control techniques, and the use of natural enemies, should take precedence
Perivascular epithelioid cell neoplasm of the uterine cervix: an unusual tumor in an unusual location
A 46-year-old woman presented for a second opinion regarding a 3–4 cm mass of the uterine cervix. A prior biopsy had been interpreted as a malignant melanoma of the cervix, resulting in a radical hysterectomy with bilateral salpingooophorectomy. This was to be followed by external beam irradiation and immunotherapy; however, given the rarity of this diagnosis, the patient sought a second opinion at our institution. Further review of the pathological material from the hysterectomy revealed a morphologically benign perivascular epithelioid cell neoplasm rather than a malignant melanoma. Close monitoring of the patient was recommended; she is currently diseasefree more than three years after her initial presentation
Comparing the Effects of Two Tillage Operations on Beneficial Epigeal Arthropod Communities and Their Associated Ecosystem Services in Sugar Beets
Beneficial arthropods provide important ecosystem services in terms of arthropod pest and weed management, but these services can be adversely affected by farming practices such as tillage. This study investigated the impact of two tillage operations (zone tillage and moldboard plow) on the activity density of several beneficial, epigeal arthropod taxa, and postdispersal weed seed and prey removal in sugar beet agroecosystems. In addition, four omnivorous ground beetle species were selected for a weed-seed choice feeding assay, whereas a single species was selected for a weed-seed age preference assay. Ground beetles were the most commonly collected taxon (via pitfall sampling), with only a few dominant species. Tillage operation did not affect ground beetle activity density; however, spider, centipede, and rove beetle activity densities were higher in the reduced-tillage treatment. Live prey consumption was similar between tillage practices, with more prey consumed during nocturnal hours. More weed seeds were consumed in the reduced-tillage treatment, whereas weed-seed preference differed between the four weed species tested [Setaria pumila (Poir.) Roem. & Schult., Echinochloa crus-galli (L.), Kochia scoparia (L.), and Chenopodium album (L.)]. In the weed-seed choice feeding assay, significantly more broad-leaf weed seeds (C. album and K. scoparia) were consumed compared with grassy weed seeds (E. crus-galli and S. pumila). No preference for seed age was detected for E. crus-galli, but Harpalus pensylvanicus (De Geer) preferred old C. album seeds over fresh seeds. Zone tillage is compatible with ecosystem services, providing critical habitat within agricultural ecosystems needed to conserve beneficial, edaphic arthropods
Comparing the Effects of Two Tillage Operations on Beneficial Epigeal Arthropod Communities and Their Associated Ecosystem Services in Sugar Beets
Published ArticleBeneficial arthropods provide important ecosystem services in terms of arthropod pest and weed management,
but these services can be adversely affected by farming practices such as tillage. This study investigated the impact
of two tillage operations (zone tillage and moldboard plow) on the activity density of several beneficial, epigeal
arthropod taxa, and postdispersal weed seed and prey removal in sugar beet agroecosystems. In addition, four
omnivorous ground beetle species were selected for a weed-seed choice feeding assay, whereas a single species
was selected for a weed-seed age preference assay. Ground beetles were the most commonly collected taxon (via
pitfall sampling), with only a few dominant species. Tillage operation did not affect ground beetle activity density;
however, spider, centipede, and rove beetle activity densities were higher in the reduced-tillage treatment. Live
prey consumption was similar between tillage practices, with more prey consumed during nocturnal hours. More
weed seeds were consumed in the reduced-tillage treatment, whereas weed-seed preference differed between
the four weed species tested [Setaria pumila (Poir.) Roem. & Schult., Echinochloa crus-galli (L.), Kochia scoparia
(L.), and Chenopodium album (L.)]. In the weed-seed choice feeding assay, significantly more broad-leaf weed
seeds (C. album and K. scoparia) were consumed compared with grassy weed seeds (E. crus-galli and S. pumila).
No preference for seed age was detected for E. crus-galli, but Harpalus pensylvanicus (De Geer) preferred old
C. album seeds over fresh seeds. Zone tillage is compatible with ecosystem services, providing critical habitat
within agricultural ecosystems needed to conserve beneficial, edaphic arthropods
Definitions and sharpness of the extratropical tropopause : a trace gas perspective
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): D23103, doi:10.1029/2004JD004982.Definitions of the extratropical tropopause are examined from the perspective of chemical composition. Fine-scale measurements of temperature, ozone, carbon monoxide, and water vapor from approximately 70 aircraft flights, with ascending and descending tropopause crossings near 40°N and 65°N, are used in this analysis. Using the relationship of the stratospheric tracer O3 and the tropospheric tracer CO, we address the issues of tropopause sharpness and where the transitions from troposphere to stratosphere occur in terms of the chemical composition. Tracer relationships indicate that mixing of stratospheric and tropospheric air masses occurs in the vicinity of the tropopause to form a transition layer. Statistically, this transition layer is centered on the thermal tropopause. Furthermore, we show that the transition is much sharper near 65°N (a region away from the subtropical jet) but spans a larger altitude range near 40°N (in the vicinity of the subtropical jet). This latter feature is consistent with enhanced stratosphere-troposphere exchange and mixing activity near the tropopause break.This work is supported in part by the
National Science Foundation through its support to the University Corporation
for Atmospheric Research, by the NASA Upper Atmosphere Research
Satellite guest investigator program, and by the NASA Atmospheric
Chemistry Modeling and Analysis Program. Work performed at the Jet
Propulsion Laboratory, California Institute of Technology, was carried out
under a contract with the National Aeronautics and Space Administration
Towards an Integrated Framework for Assessing the Vulnerability of Species to Climate Change
Climate change is a major threat to global biodiversity. A novel integrated framework to assess vulnerability and prioritize research and management action aims to improve our ability to respond to this emerging crisis
LSST: from Science Drivers to Reference Design and Anticipated Data Products
(Abridged) We describe here the most ambitious survey currently planned in
the optical, the Large Synoptic Survey Telescope (LSST). A vast array of
science will be enabled by a single wide-deep-fast sky survey, and LSST will
have unique survey capability in the faint time domain. The LSST design is
driven by four main science themes: probing dark energy and dark matter, taking
an inventory of the Solar System, exploring the transient optical sky, and
mapping the Milky Way. LSST will be a wide-field ground-based system sited at
Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m
effective) primary mirror, a 9.6 deg field of view, and a 3.2 Gigapixel
camera. The standard observing sequence will consist of pairs of 15-second
exposures in a given field, with two such visits in each pointing in a given
night. With these repeats, the LSST system is capable of imaging about 10,000
square degrees of sky in a single filter in three nights. The typical 5
point-source depth in a single visit in will be (AB). The
project is in the construction phase and will begin regular survey operations
by 2022. The survey area will be contained within 30,000 deg with
, and will be imaged multiple times in six bands, ,
covering the wavelength range 320--1050 nm. About 90\% of the observing time
will be devoted to a deep-wide-fast survey mode which will uniformly observe a
18,000 deg region about 800 times (summed over all six bands) during the
anticipated 10 years of operations, and yield a coadded map to . The
remaining 10\% of the observing time will be allocated to projects such as a
Very Deep and Fast time domain survey. The goal is to make LSST data products,
including a relational database of about 32 trillion observations of 40 billion
objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures
available from https://www.lsst.org/overvie
In Vitro Effect of Porphyromonas gingivalis Methionine Gamma Lyase on Biofilm Composition and Oral Inflammatory Response
Methanethiol (methyl mercaptan) is an important contributor to oral malodour and periodontal tissue destruction. Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum are key oral microbial species that produce methanethiol via methionine gamma lyase (mgl) activity. The aim of this study was to compare an mgl knockout strain of P. gingivalis with its wild type using a 10-species biofilm co-culture model with oral keratinocytes and its effect on biofilm composition and inflammatory cytokine production. A P. gingivalis mgl knockout strain was constructed using insertion mutagenesis from wild type W50 with gas chromatographic head space analysis confirming lack of methanethiol production. 10-species biofilms consisting of Streptococcus mitis, Streptococcus oralis, Streptococcus intermedius, Fusobacterium nucleatum ssp polymorphum, Fusobacterium nucleatum ssp vincentii, Veillonella dispar, Actinomyces naeslundii, Prevotella intermedia and Aggregatibacter actinomycetemcomitans with either the wild type or mutant P. gingivalis were grown on Thermanox cover slips and used to stimulate oral keratinocytes (OKF6-TERT2), under anaerobic conditions for 4 and 24 hours. Biofilms were analysed by quantitative PCR with SYBR Green for changes in microbial ecology. Keratinocyte culture supernatants were analysed using a multiplex bead immunoassay for cytokines. Significant population differences were observed between mutant and wild type biofilms; V. dispar proportions increased (p<0.001), whilst A. naeslundii (p<0.01) and Streptococcus spp. (p<0.05) decreased in mutant biofilms. Keratinocytes produced less IL-8, IL-6 and IL-1α when stimulated with the mutant biofilms compared to wild type. Lack of mgl in P. gingivalis has been shown to affect microbial ecology in vitro, giving rise to a markedly different biofilm composition, with a more pro-inflammatory cytokine response from the keratinocytes observed. A possible role for methanethiol in biofilm formation and cytokine response with subsequent effects on oral malodor and periodontitis is suggested
Broadening the horizon – level 2.5 of the HUPO-PSI format for molecular interactions
BACKGROUND: Molecular interaction Information is a key resource in modern biomedical research. Publicly available data have previously been provided in a broad array of diverse formats, making access to this very difficult. The publication and wide implementation of the Human Proteome Organisation Proteomics Standards Initiative Molecular Interactions (HUPO PSI-MI) format in 2004 was a major step towards the establishment of a single, unified format by which molecular interactions should be presented, but focused purely on protein-protein interactions.
RESULTS: The HUPO-PSI has further developed the PSI-MI XML schema to enable the description of interactions between a wider range of molecular types, for example nucleic acids, chemical entities, and molecular complexes. Extensive details about each supported molecular interaction can now be captured, including the biological role of each molecule within that interaction, detailed description of interacting domains, and the kinetic parameters of the interaction. The format is supported by data management and analysis tools and has been adopted by major interaction data providers. Additionally, a simpler, tab-delimited format MITAB2.5 has been developed for the benefit of users who require only minimal information in an easy to access configuration.
CONCLUSION: The PSI-MI XML2.5 and MITAB2.5 formats have been jointly developed by interaction data producers and providers from both the academic and commercial sector, and are already widely implemented and well supported by an active development community. PSI-MI XML2.5 enables the description of highly detailed molecular interaction data and facilitates data exchange between databases and users without loss of information. MITAB2.5 is a simpler format appropriate for fast Perl parsing or loading into Microsoft Excel
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