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The first measurement of lepton-jet momentum imbalance and azimuthal correlation in lepton-proton scattering at high momentum transfer is presented. These data, taken with the H1 detector at HERA, are corrected for detector effects using an unbinned machine learning algorithm (multifold), which considers eight observables simultaneously in this first application. The unfolded cross sections are compared with calculations performed within the context of collinear or transverse-momentum-dependent factorization in quantum chromodynamics as well as Monte Carlo event generators.
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Although it is logical to think that mycorrhizal mushroom production should be somehow related to the growth of the trees from which the fungi obtain carbohydrates, little is known about how mushroom yield patterns are related to tree performance. In this study, we delved into the understanding of the relationships between aboveground fungal productivity, tree radial growth patterns and climatic conditions across three latitudinally different bioclimatic regions encompassing Mediterranean, temperate and boreal forest ecosystems in Europe. For this purpose, we used a large assemblage of long-term data of weekly or biweekly mushroom yield monitoring in Spain, Switzerland and Finland. We analysed the relationships between annual mushroom yield (considering both biomass and number of sporocarps per unit area), tree ring features (tree ring, earlywood and latewood widths), and meteorological conditions (i.e. precipitation and temperature of summer and autumn) from different study sites and forest ecosystems, using both standard and partial correlations. Moreover, we fitted predictive models to estimate mushroom yield from mycorrhizal and saprotrophic fungal guilds based on climatic and dendrochronological variables. Significant synchronies between mushroom yield and climatic and dendrochronological variables were mostly found in drier Mediterranean sites, while few or no significant correlations were found in the boreal and temperate regions. We observed positive correlations between latewood growth and mycorrhizal mushroom biomass only in some Mediterranean sites, this relationship being mainly mediated by summer and autumn precipitation. Under more water-limited conditions, both the seasonal wood production and the mushroom yield are more sensitive to precipitation events, resulting in higher synchrony between both variables. This comparative study across diverse European forest biomes and types provides new insights into the relationship between mushroom productivity, tree growth and weather conditions.
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Agaricales/fisiología , Clima , Bosques , Árboles/crecimiento & desarrollo , Agaricales/crecimiento & desarrollo , Europa (Continente) , Micorrizas/fisiología , Densidad de PoblaciónRESUMEN
The strong coupling constant α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α s ( m Z ) at the Z-boson mass m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.
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A dominantly inherited form of distal myopathy with onset in early childhood was first reported in a 4-generation Australian family in 1995. In the present report we provide further information on the clinical phenotype and natural history of this myopathy, and on the electromyogram and magnetic resonance imaging findings in affected individuals. The pattern of muscle involvement was similar to that in the 'tibial' forms of distal myopathy such as the Finnish (Udd) and Markesbery-Griggs types, with additional involvement of the finger extensors and of some more proximal limb and neck muscles. However, the age of onset was earlier than in these other myopathies and rimmed vacuoles were not found in biopsies from two affected individuals. Evidence of possible anticipation was found in one branch of the family. The gene locus for this myopathy had been mapped to 14q11.2-q13. The linkage region has been refined to a 24 cM region between D14S283 and D14S49 and mutations have been excluded in the PABP2 gene for oculopharyngeal muscular dystrophy which lies within this region.
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Cromosomas Humanos Par 14 , Distrofias Musculares/genética , Distrofias Musculares/patología , Adolescente , Adulto , Edad de Inicio , Anciano , Niño , Preescolar , Salud de la Familia , Femenino , Ligamiento Genético , Humanos , Imagen por Resonancia Magnética , Masculino , Músculo Esquelético/patología , Linaje , FenotipoRESUMEN
Disease-specific PrP (PrP(Sc)) is at least part of the infectious particle (prion) causing bovine spongiform encephalopathy (BSE) or scrapie in sheep. Digestion with protease allows a distinction between normal PrP (PrP(C)) and PrP(Sc) i.e. PrP(C) is completely digested while PrP(Sc) is cleaved at the N-terminus leading to a fragment of reduced molecular weight (PrP 27-30). Detection of this fragment by Western blotting has been described more than a decade ago for rodent PrP. We have now optimized the technique in order to allow rapid analysis of hundreds of samples per day. Here we report the application of this technique to the analysis of 3000 regularly slaughtered cattle from Swiss abattoirs. For comparison all the animals were subsequently examined by classical methods (i.e. histology and immunohistochemistry). All but one animal were negative for BSE by all methods. The Western blot positive animal was confirmed to be a BSE case and the carcass was removed from the food chain. We conclude that it is feasible to examine slaughtered cattle on a routine basis without causing delays to the meat processing industry.
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Mataderos , Western Blotting/métodos , Encefalopatía Espongiforme Bovina/diagnóstico , Encefalopatía Espongiforme Bovina/epidemiología , Proteínas PrPSc/análisis , Animales , Encéfalo/metabolismo , Bovinos , Bulbo Raquídeo/química , Vigilancia de la Población , SuizaRESUMEN
In vitro and greenhouse biotests were carried out to study the effects of various concentrations of crude oil on the mycorrhizosphere and the ability of ectomycorrhizal fungi to colonise Norway spruce and poplar seedlings grown on contaminated soil. Ectomycorrhizal fungi grown in pure cultures showed a variety of reactions to crude oil, ranging from growth stimulation to total inhibition of growth, depending on the species of fungi. Germination of poplar and spruce seeds was not significantly affected. The growth of spruce seedlings was not affected by crude oil, whereas that of poplar seedlings was significantly reduced at high concentrations. None of the concentrations had any effect on the degree of ectomycorrhizal and endomycorrhizal colonisation of poplar. With spruce, however, the ectomycorrhizal fungi showed species-specific reactions to increasing concentrations, in accordance with the results of the pure culture test. The length of time between soil contamination and seeding affects both seedling growth and the mycorrhizal infection potential of the soil. The results confirm the importance of mycorrhizal fungi in the bioremediation of soils contaminated by crude oil.
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The present study aimed to elucidate the influence of drought and elevated temperature on relative abundance and functioning of the ectomycorrhizal fungus Cenococcum geophilum on three oak species differing in adaptation to a warm and dry climate. The experiment QUERCO comprised three Quercus species (Q. robur, Q. petraea, Q. pubescens) grown for 3 years under four treatments: elevated air temperature, drought, a combination of the two, and control. Fine root samples were analysed for relative abundance and potential extracellular enzyme activities of ectomycorrhizae of C. geophilum, a fungal species known to be drought resistant. The relative abundance of C. geophilum on the roots of the oak species was significantly increased by temperature, decreased by drought, but unchanged in the combined treatment compared to the control. Although the extent of treatment effects differed among oak species, no significant influence of tree species on relative abundance of C. geophilum was detected. Exoenzyme activities of C. geophilum on Q. robur and Q. petraea (but not Q. pubescens) significantly increased in the combined treatment, but for all oak species were reduced under drought and air warming alone compared to the control. There was a significant negative correlation between abundance of C. geophilum and its leucine aminopeptidase activity. As this enzyme is not frequent among ectomycorrhizal fungi, this emphasises the functional importance of C. geophilum in the ectomycorrhizal community. Our results indicate that increased temperature and drought will influence the relative abundance and enzyme activity of C. geophilum. However, both the Quercus species and C. geophilum tolerated warming and strong drought.
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Adaptación Fisiológica , Sequías , Hongos , Calor , Micorrizas , Quercus/microbiología , Estrés Fisiológico , Aire , Clima , Hongos/enzimología , Hongos/crecimiento & desarrollo , Calentamiento Global , Leucil Aminopeptidasa/metabolismo , Micorrizas/enzimología , Micorrizas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Especificidad de la Especie , AguaRESUMEN
We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test the activity of arbuscular mycorrhizal (AM) fungi in these soils. Soil samples were taken from (1) front of the shooting house (HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantago lanceolata) growing naturally within the shooting ranges were also collected and the colonization of its roots by mycorrhizal fungi was measured. The number of AM spores in the soils was significantly reduced concomitant with the increase in the degree of soil contamination with metals. In Zuchwil, mycorrhizal fungi equally colonized roots of Ribwort plantain sampled from BACKSTOP and HOUSE. In Oberuzwil, however, plants from BACKSTOP had lower colonization when compared with those sampled from HOUSE. Colonization of leek was strongly reduced in the BACKSTOP soil of Zuchwil and slightly reduced in the BACKSTOP soil of Oberuzwil when compared with plants grown in respective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb and Zn in the leaves of leek grown in the BACKSTOP soil was within the range considered toxic for human consumption. This points to the high degree of bioavailability of these metal in these soils. Significant decrease in the number of mycorrhizal spores in the BACKSTOP soils in Zuchwil and the low colonization of leek roots grown in these soils point to possible changes in the species diversity of mycorrhizal fungi in these soils.
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Allium/crecimiento & desarrollo , Metales Pesados/farmacocinética , Micorrizas/fisiología , Raíces de Plantas/microbiología , Contaminantes del Suelo/farmacocinética , Allium/fisiología , Contaminación de Alimentos , Humanos , Plantago/fisiologíaRESUMEN
In this report we document the results of several independent studies testing the sensitivity, specificity and reliability of the Prionics Western blotting (PWB) procedure to detect bovine and ovine disease-specific, protease-resistant prion protein (PrP(Sc)). Validation of the technique was obtained by blind analysis of samples from cattle affected with bovine spongiform encephalopathy (BSE), clinically normal animals or cattle with neurological diseases unrelated to BSE. Overall, very high sensitivity, specificity and reliability was observed. It became clear that sampling of the correct brain region and the method used for protein extraction are important factors for correct diagnosis. Furthermore, we tested the usefulness of the PWB technique as an instrument for surveillance purposes. We analyzed animals from a culling scheme as well as older animals from abattoirs to determine the number of subclinical BSE cases detectable by histopathological examination, immunohistochemistry for PrP(Sc) and PWB. In both studies, BSE-affected animals with no overt clinical symptoms were detected. These results demonstrate the usefulness of the PWB procedure in surveillance systems serving as a rapid diagnostic tool to identify animals subclinically infected with BSE.