779 research outputs found

    Shorescape-level factors drive distribution and condition of a salt marsh facilitator (Geukensia Demissa)

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    Ribbed mussels (Geukensia demissa) are a highly abundant bivalve filter feeder throughout the salt marshes of the U.S. Atlantic Coast. These mussels form a mutualistic relationship with smooth cordgrass Spartina alterniflora wherein the grass provides habitat and shade to the mussels, and the mussels stabilize the sediment and fertilize the grass. Salt marshes are, however, rapidly changing and eroding as humans modify the coast, and the rate of sea level rise is accelerating. In order to understand how ribbed mussels may respond to their changing habitat, we collected mussel density and distribution data from 30 marshes covering the range of geomorphic settings found in lower Chesapeake Bay. We used a combination of in situ and GIS-derived spatial variables to develop spatially applied models of ribbed mussel density and physical condition. Of the estimated 1.06 billion ribbed mussels in Virginia, we found that mussels were most abundant along the front edge of marshes in wide creeks, rivers, or bays with dense Spartina and minimal proximal forest, set in agriculturally dominated areas. In contrast, mussel condition was highest in fringing marshes located in narrow tidal creeks. Ribbed mussels responded to factors at a variety of scales, ranging from extremely local (0.5 m) to larger shorescapes (≥300 m). The methods that we used to create models linking both aquatic and terrestrial variables to explain the variation in ribbed mussel populations along the shoreline provide a valuable tool for identifying baselines and assessing potential for change across estuary-level spatial scales not only for ribbed mussels in the Chesapeake Bay, but also for other sessile, intertidal species in other systems

    Melhoramento do feijão ao alcance de todos: I. cruzamentos.

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    A Cryogenic Silicon Interferometer for Gravitational-wave Detection

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    The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument that will have 5 times the range of Advanced LIGO, or greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby universe, as well as observing the universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

    Behind the stiff upper lip: war narratives of older men with dementia.

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    The concept of the stiff upper lip stands as a cultural metaphor for the repression and figurative ¿biting back¿ of traumatic experience, particularly in military contexts. For men born in the first half of the 20th century, maintaining a stiff upper lip involved the ability to exert high levels of cognitive control over the subjective, visceral and emotional domains of experience. In the most common forms of dementia, which affect at least one in five men now in their 80s and 90s, this cognitive control is increasingly lost. One result is that, with the onset of dementia, men who have in the intervening years maintained a relative silence about their wartime experiences begin to disclose detailed memories of such events, in some cases for the first time. This article draws on narrative biographical data from three men with late-onset dementia who make extensive reference to their experience of war. The narratives of Sid, Leonard and Nelson are used to explore aspects of collective memory of the two World Wars, and the socially constructed masculinities imposed on men who grew up and came of age during those decades. The findings show that in spite of their difficulties with short term memory, people with dementia can contribute rich data to cultural studies research. Some aspects of the narratives discussed here may also be considered to work along the line of the counter-hegemonic, offering insights into lived experiences of war that have been elided in popular culture in the post-War years

    Gravitational Waves From Known Pulsars: Results From The Initial Detector Era

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    We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom

    First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

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    Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

    CAnceR IN PreGnancy (CARING) - a retrospective study of cancer diagnosed during pregnancy in the United Kingdom

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    BACKGROUND: The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population.METHODS: In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020).RESULTS: Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%.CONCLUSIONS: This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.</p
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