125 research outputs found

    Broadband Meter-Wavelength Observations of Ionospheric Scintillation

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    Intensity scintillations of cosmic radio sources are used to study astrophysical plasmas like the ionosphere, the solar wind, and the interstellar medium. Normally these observations are relatively narrow band. With Low Frequency Array (LOFAR) technology at the Kilpisj\"arvi Atmospheric Imaging Receiver Array (KAIRA) station in northern Finland we have observed scintillations over a 3 octave bandwidth. ``Parabolic arcs'', which were discovered in interstellar scintillations of pulsars, can provide precise estimates of the distance and velocity of the scattering plasma. Here we report the first observations of such arcs in the ionosphere and the first broad-band observations of arcs anywhere, raising hopes that study of the phenomenon may similarly improve the analysis of ionospheric scintillations. These observations were made of the strong natural radio source Cygnus-A and covered the entire 30-250\,MHz band of KAIRA. Well-defined parabolic arcs were seen early in the observations, before transit, and disappeared after transit although scintillations continued to be obvious during the entire observation. We show that this can be attributed to the structure of Cygnus-A. Initial results from modeling these scintillation arcs are consistent with simultaneous ionospheric soundings taken with other instruments, and indicate that scattering is most likely to be associated more with the topside ionosphere than the F-region peak altitude. Further modeling and possible extension to interferometric observations, using international LOFAR stations, are discussed.Comment: 11 pages, 17 figure

    Extensive sampling and thorough taxonomic assessment of Afrotropical Rhyssinae (Hymenoptera, Ichneumonidae) reveals two new species and demonstrates the limitations of previous sampling efforts

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    Tropical forest invertebrates, such as the parasitoid wasp family Ichneumonidae, are poorly known. This work reports some of the first results of an extensive survey implemented in Kibale National Park, Uganda. A total of 456 individuals was caught of the subfamily Rhyssinae Morley, 1913, which in the Afrotropical region was previously known from only 30 specimens. Here, the six species found at the site are described and the Afrotropical Rhyssinae are reviewed. Two new species, Epirhyssa johanna Hopkins, sp. nov. and E. quagga sp. nov., are described and a key, diagnostic characters, and descriptions for all 13 known Afrotropical species are provided, including the first description of the male of Epirhyssa overlaeti Seyrig, 1937. Epirhyssa gavinbroadi Rousse & van Noort, 2014, syn. nov. is proposed to be a synonym of E. uelensis Benoit, 1951. Extensive sampling with Malaise traps gave an unprecedented sample size, and the method is recommended for other poorly known tropical areas.</p

    A minor role of asparaginase in predisposing to cerebral venous thromboses in adult acute lymphoblastic leukemia patients

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    Cerebral venous thrombosis (CVT) covers up to a third of all venous thromboses (VTs) detected in patients with acute lymphoblastic leukemia (ALL). It usually hampers patients' lives and may also endanger efficient leukemia treatment. Although many factors have been suggested to account for an elevated risk of VTs in patients with ALL, there still is a lack of studies focusing on CVTs and especially in the setting of adult ALL patients. We studied in our retrospective population-based cohort the occurrence, characteristics, as well as risk factors for VTs in 186 consecutively diagnosed Finnish adult ALL patients treated with a national pediatric-inspired treatment protocol ALL2000. In the risk factor analyses for VTs we found a distinction of the characteristics of the patients acquiring CVT from those with other kinds of VTs or without thrombosis. In contrast to previous studies we were also able to compare the effects of asparaginase in relation to CVT occurrence. Notably, more than half of the CVTs were diagnosed prior the administration of asparaginase which accentuates the role of other risk factors on the pathophysiology of CVT compared to truncal or central venous line (CVL) VTs in adult ALL patients

    Acquired flavor acceptance and intake facilitated by monosodium glutamate in humans

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    Monosodium glutamate (MSG) is known to enhance liking for the flavor of savory foods, but whether associations between flavors and effects of MSG lead to changes in subsequent liking and intake for the flavor alone is unclear. To test this, 32 volunteers evaluated and consumed a novel savory soup with no added MSG before and after four training sessions where the same soup was consumed either unchanged (Control) or with added MSG. The addition of MSG during training increased both pleasantness and savory character of the soup and resulted in a larger increase in rated pleasantness of the soup in the MSG-trained relative to control condition when the soup was re-evaluated Post-training without MSG. There was also a significant increase in voluntary soup intake Post-training after the soup had been paired with MSG but not in the Control condition, and rated hunger increased more after tasting the soup Post-training in the MSG-trained but not Control condition. These findings demonstrate that co-experience of a savory flavor and MSG can result in increased subsequent liking and intake for the flavor in the absence of MSG, and possible explanations for how MSG reinforces learning are discussed

    Does acute or habitual protein deprivation influence liking for monosodium glutamate?

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    The umami flavour generated by monosodium glutamate (MSG) has been proposed as the marker for the presence of protein in foods. As protein is the most closely regulated macronutrient in the diet, the present study addressed whether acute protein deprivation, habitual protein intake or a combination of the two influenced liking for the taste of MSG. 24 low-restraint male participants (mean age: 22; BMI: 23) consumed either their habitual breakfast (baseline), a low protein breakfast (breakfast meal with low protein milk and milkshake) or a high protein breakfast (breakfast meal with high protein milk and milkshake) on three different days, and then evaluated the acceptability of umami (MSG), salty (NaCl) or sweet (Acesulphame K) tastes at low or high concentrations in a soup context at lunchtime. Participants also completed a habitual protein intake questionnaire (39-item protein Food Frequency Questionnaire). Liking for all tastes was higher on the low than on the high protein day, and NaCl and Acesulphame K were liked less on both protein manipulation days when compared to the no added flavour control. Habitual protein intake was not related to liking for MSG stimuli alone but habitual high protein consumers rated a high concentration of MSG as more pleasant than any other taste when in protein deficit. Overall, these findings suggest that liking for high MSG concentrations may be moderated by nutritional need in high protein consumers

    A High Density Consensus Map of Rye (Secale cereale L.) Based on DArT Markers

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    L.) is an economically important crop, exhibiting unique features such as outstanding resistance to biotic and abiotic stresses and high nutrient use efficiency. This species presents a challenge to geneticists and breeders due to its large genome containing a high proportion of repetitive sequences, self incompatibility, severe inbreeding depression and tissue culture recalcitrance. The genomic resources currently available for rye are underdeveloped in comparison with other crops of similar economic importance. The aim of this study was to create a highly saturated, multilocus linkage map of rye via consensus mapping, based on Diversity Arrays Technology (DArT) markers.Recombinant inbred lines (RILs) from 5 populations (564 in total) were genotyped using DArT markers and subjected to linkage analysis using Join Map 4.0 and Multipoint Consensus 2.2 software. A consensus map was constructed using a total of 9703 segregating markers. The average chromosome map length ranged from 199.9 cM (2R) to 251.4 cM (4R) and the average map density was 1.1 cM. The integrated map comprised 4048 loci with the number of markers per chromosome ranging from 454 for 7R to 805 for 4R. In comparison with previously published studies on rye, this represents an eight-fold increase in the number of loci placed on a consensus map and a more than two-fold increase in the number of genetically mapped DArT markers.Through the careful choice of marker type, mapping populations and the use of software packages implementing powerful algorithms for map order optimization, we produced a valuable resource for rye and triticale genomics and breeding, which provides an excellent starting point for more in-depth studies on rye genome organization

    European Red List of Habitats Part 1. Marine habitats

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    The European Red List of Habitats provides an overview of the risk of collapse (degree of endangerment) of marine, terrestrial and freshwater habitats in the European Union (EU28) and adjacent regions (EU28+), based on a consistent set of categories and criteria, and detailed data and expert knowledge from involved countries1. A total of 257 benthic marine habitat types were assessed. In total, 19% (EU28) and 18% (EU28+) of the evaluated habitats were assessed as threatened in categories Critically Endangered, Endangered and Vulnerable. An additional 12% were Near Threatened in the EU28 and 11% in the EU28+. These figures are approximately doubled if Data Deficient habitats are excluded. The percentage of threatened habitat types differs across the regional seas. The highest proportion of threatened habitats in the EU28 was found in the Mediterranean Sea (32%), followed by the North-East Atlantic (23%), the Black Sea (13%) and then the Baltic Sea (8%). There was a similar pattern in the EU28+. The most frequently cited pressures and threats were similar across the four regional seas: pollution (eutrophication), biological resource use other than agriculture or forestry (mainly fishing but also aquaculture), natural system modifications (e.g. dredging and sea defence works), urbanisation and climate change. Even for habitats where the assessment outcome was Data Deficient, the Red List assessment process has resulted in the compilation of a substantial body of useful information to support the conservation of marine habitats
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