2,070 research outputs found
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Ag Ent Peregrinations at the Central Ferry Research Station, Eastern Washington
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Insect Pests and Beneficials in Small Grains Under Conservation Tillage in the Semiarid Wheat-Fallow Region of Washington State
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Effect of Tillage, Cultivar and Cropping System on Aphid Populations in Small Grains of Central Washington
Bird pollination of Canary Island endemic plants
The Canary Islands are home to a guild of endemic, threatened bird pollinated plants. Previous work has suggested that these plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently they appear to be have co-opted passerine birds as sub-optimal pollinators. To test this idea we carried out a quantitative study of the pollination biology of three of the bird pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and bee pollinators. We measured pollinator visitation rates, nectar standing crops, as well as seed set and pollen removal and deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10days) of Canarina and Isoplexis suggests that they have evolved bird pollination system that effectively exploits these low frequency non-specialist pollen vectors and is in no way suboptimal. Seed set in two of the three species was high, and was significantly reduced or zero in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self incompatible horticultural clones of a single genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff (Phylloscopus canariensis) was an effective pollinator of these species
Dust Production and Mass Loss in the Galactic Globular Cluster NGC 362
We investigate dust production and stellar mass loss in the Galactic globular
cluster NGC 362. Due to its close proximity to the Small Magellanic Cloud
(SMC), NGC 362 was imaged with the IRAC and MIPS cameras onboard the Spitzer
Space Telescope as part of the Surveying the Agents of Galaxy Evolution
(SAGE-SMC) Spitzer Legacy program. We detect several cluster members near the
tip of the Red Giant Branch that exhibit infrared excesses indicative of
circumstellar dust and find that dust is not present in measurable quantities
in stars below the tip of the Red Giant Branch. We modeled the spectral energy
distribution (SED) of the stars with the strongest IR excess and find a total
cluster dust mass-loss rate of 3.0(+2.0/-1.2) x 10^-9 solar masses per year,
corresponding to a gas mass-loss rate of 8.6(+5.6/-3.4) x 10^-6 solar masses
per year, assuming [Fe/H] = -1.16. This mass loss is in addition to any
dust-less mass loss that is certainly occurring within the cluster. The two
most extreme stars, variables V2 and V16, contribute up to 45% of the total
cluster dust-traced mass loss. The SEDs of the more moderate stars indicate the
presence of silicate dust, as expected for low-mass, low-metallicity stars.
Surprisingly, the SED shapes of the stars with the strongest mass-loss rates
appear to require the presence of amorphous carbon dust, possibly in
combination with silicate dust, despite their oxygen-rich nature. These results
corroborate our previous findings in omega Centauri.Comment: 13 pages, 11 figures. Accepted to Ap
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The impact of mental health recovery narratives on recipients experiencing mental health problems: Qualitative analysis and change model.
BACKGROUND: Mental health recovery narratives are stories of recovery from mental health problems. Narratives may impact in helpful and harmful ways on those who receive them. The objective of this paper is to develop a change model identifying the range of possible impacts and how they occur. METHOD: Semi-structured interviews were conducted with adults with experience of mental health problems and recovery (n = 77). Participants were asked to share a mental health recovery narrative and to describe the impact of other people's recovery narratives on their own recovery. A change model was generated through iterative thematic analysis of transcripts. RESULTS: Change is initiated when a recipient develops a connection to a narrator or to the events descripted in their narrative. Change is mediated by the recipient recognising experiences shared with the narrator, noticing the achievements or difficulties of the narrator, learning how recovery happens, or experiencing emotional release. Helpful outcomes of receiving recovery narratives are connectedness, validation, hope, empowerment, appreciation, reference shift and stigma reduction. Harmful outcomes are a sense of inadequacy, disconnection, pessimism and burden. Impact is positively moderated by the perceived authenticity of the narrative, and can be reduced if the recipient is experiencing a crisis. CONCLUSIONS: Interventions that incorporate the use of recovery narratives, such as peer support, anti-stigma campaigns and bibliotherapy, can use the change model to maximise benefit and minimise harms from narratives. Interventions should incorporate a diverse range of narratives available through different mediums to enable a range of recipients to connect with and benefit from this material. Service providers using recovery narratives should preserve authenticity so as to maximise impact, for example by avoiding excessive editing
Practical Tools to Implement Massive Parallel Pyrosequencing of PCR Products in Next Generation Molecular Diagnostics
Despite improvements in terms of sequence quality and price per basepair, Sanger sequencing remains restricted to screening of individual disease genes. The development of massively parallel sequencing (MPS) technologies heralded an era in which molecular diagnostics for multigenic disorders becomes reality. Here, we outline different PCR amplification based strategies for the screening of a multitude of genes in a patient cohort. We performed a thorough evaluation in terms of set-up, coverage and sequencing variants on the data of 10 GS-FLX experiments (over 200 patients). Crucially, we determined the actual coverage that is required for reliable diagnostic results using MPS, and provide a tool to calculate the number of patients that can be screened in a single run. Finally, we provide an overview of factors contributing to false negative or false positive mutation calls and suggest ways to maximize sensitivity and specificity, both important in a routine setting. By describing practical strategies for screening of multigenic disorders in a multitude of samples and providing answers to questions about minimum required coverage, the number of patients that can be screened in a single run and the factors that may affect sensitivity and specificity we hope to facilitate the implementation of MPS technology in molecular diagnostics
Ecological Release and Venom Evolution of a Predatory Marine Snail at Easter Island
BACKGROUND:Ecological release is coupled with adaptive radiation and ecological diversification yet little is known about the molecular basis of phenotypic changes associated with this phenomenon. The venomous, predatory marine gastropod Conus miliaris has undergone ecological release and exhibits increased dietary breadth at Easter Island. METHODOLOGY/PRINCIPAL FINDINGS:We examined the extent of genetic differentiation of two genes expressed in the venom of C. miliaris among samples from Easter Island, American Samoa and Guam. The population from Easter Island exhibits unique frequencies of alleles that encode distinct peptides at both loci. Levels of divergence at these loci exceed observed levels of divergence observed at a mitochondrial gene region at Easter Island. CONCLUSIONS/SIGNIFICANCE:Patterns of genetic variation at two genes expressed in the venom of this C. miliaris suggest that selection has operated at these genes and contributed to the divergence of venom composition at Easter Island. These results show that ecological release is associated with strong selection pressures that promote the evolution of new phenotypes
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