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Berlin Brandenburg

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  • PMC (PubMed Central)  (2,234)
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  • 1
    Language: English
    In: Emerging infectious diseases, September 2011, Vol.17(9), pp.1767-9
    Description: To the Editor: Diphtheria and diphtheria-like illness are caused by Corynebacterium spp. that harbor the diphtheria toxin–encoding tox gene. Recently in many industrialized countries, cases of diphtheria-like infection caused by toxigenic C. ulcerans have outnumbered those caused by toxigenic C. diphtheriae (1,2). C. ulcerans infection was originally associated with consumption of raw milk and dairy products or contact with cattle, but C. ulcerans has increasingly been isolated from domestic animals such as pet dogs and cats (3–5). So far, isolation of an identical toxigenic C. ulcerans strain from an animal and its owner has been documented only for dogs (3,4) and a pig (6). We report the isolation of an identical toxigenic C. ulcerans strain from an asymptomtic pet cat and a person with pharyngeal diphtheria-like illness; therefore, it might be speculated that the woman has acquired her infection from the cat.
    Keywords: Cat Diseases -- Diagnosis ; Corynebacterium -- Isolation & Purification ; Corynebacterium Infections -- Diagnosis
    ISSN: 10806040
    E-ISSN: 1080-6059
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  • 2
    Language: English
    In: Plant and Soil, 2012, Vol.358(1), pp.349-369
    Description: Background and aims: Replacement of beech by spruce is associated with changes in soil acidity, soil structure and humus form, which are commonly ascribed to the recalcitrance of spruce needles. It is of practical relevance to know how much beech must be admixed to pure spruce stands in order to increase litter decomposition and associated nutrient cycling. We addressed the impact of tree species mixture within forest stands and within litter on mass loss and nutritional release from litter. Methods: Litter decomposition was measured in three adjacent stands of pure spruce (Picea abies), mixed beech-spruce and pure beech (Fagus sylvatica) on three nutrient-rich sites and three nutrient-poor sites over a three-year period using the litterbag method (single species and mixed species bags). Results: Mass loss of beech litter was not higher than mass loss of spruce litter. Mass loss and nutrient release were not affected by litter mixing. Litter decay indicated non-additive patterns, since similar remaining masses under pure beech (47%) and mixed beech-spruce (48%) were significantly lower than under pure spruce stands (67%). Release of the main components of the organic substance (C sub(org), N sub(tot), P, S, lignin) and associated K were related to mass loss, while release of other nutrients was not related to mass loss. Conclusions: In contradiction to the widely held assumption of slow decomposition of spruce needles, we conclude that accumulation of litter in spruce stands is not caused by recalcitrance of spruce needles to decay; rather adverse environmental conditions in spruce stands retard decomposition. Mixed beech-spruce stands appear to be as effective as pure beech stands in counteracting these adverse conditions.
    Keywords: Decomposition ; Fagus sylvatica ; Litter quality ; Litterbag ; Mixing effects ; Picea abies
    ISSN: 0032-079X
    E-ISSN: 1573-5036
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  • 3
    Language: English
    In: Plant and Soil, 2014, Vol.377(1), pp.217-234
    Description: Background and aims It is of practical relevance to know how much beech must be admixed to pure spruce stands in order to increase litter decomposition and associated nutrient cycling, since the formation of thick organic layers is commonly ascribed to the recalcitrance of spruce needles. We addressed the impact of tree species mixture within forest stands and within litter on mass loss and nutritional release from litter. Methods Litter decomposition was measured in three adjacent stands of pure spruce (Picea abies), mixed beech-spruce and pure beech (Fagus sylvatica)on a nutrient-rich site and a nutrient-poor site over a 2-year period using litterbags which were filled with five different mixtures of beech and spruce litter. Results Mass loss of beech litter was not higher than mass loss of spruce litter. Decay was primarily affected by tree species composition of the incubation stand and was faster in (mixed) beech forests stands than in spruce forests, while the influence of litter species and their mixtures on decay rates was small. Net transfers of nutrients between the two litter species (direct effects) in the mixed bags were minimal, since initial beech and spruce litter did not have different litter quality. However, in a few cases indirect effects (e.g., changing decomposer abundance and activity) caused non additive patterns for the totals within the mixed bags, hastening decomposition within the first year. Conclusions Greater accumulation of litter in spruce compared to beech stands is not a consequence of the inherent recalcitrance of needles. Adverse environmental conditions in spruce stands retard decomposition. Indirect effects on decomposition caused by stand mixture are not mimicked by litter mixtures within mesh bags. Keywords Decomposition * Fagus sylvatica * Litter quality * Litterbag * Mixing effects * Picea abies
    Keywords: Decomposition ; Fagus sylvatica ; Litter quality ; Litterbag ; Mixing effects ; Picea abies
    ISSN: 0032-079X
    E-ISSN: 1573-5036
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  • 4
    In: PLoS ONE, 2017, Vol.12(2)
    Description: Costly signaling theory provides an explanation for why humans are willing to a pay a premium for conspicuous products such as luxury brand-labeled clothing or conspicuous environmentally friendly cars. According to the theory, the extra cost of such products is a signal of social status and wealth and leads to advantages in social interactions for the signaler. A previous study found positive evidence for the case of luxury brand labels. However, an issue of this study was that some of the experiments were not conducted in a perfectly double-blind manner. I resolved this by replicating variations of the original design in a double-blind procedure. Additionally, besides the luxury label condition, I introduced a “green” label condition. Thus, the hypothesis that signaling theory is able to explain pro-environmental behavior was tested for the first time in a natural field setting. Further, I conducted experiments in both average and below-average socioeconomic neighborhoods, where, according to signaling theory, the effects of luxury signals should be even stronger. In contrast to the original study, I did not find positive effects of the luxury brand label in any of the five experiments. Nor did I find evidence for a green-signaling effect. Moreover, in poor neighborhoods a negative tendency of the luxury label actually became evident. This suggests that a signaling theory explanation of costly labels must take into account the characteristics of the observers, e.g. their social status.
    Keywords: Research Article ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Social Sciences ; Biology And Life Sciences ; Social Sciences ; Biology And Life Sciences ; Social Sciences ; Social Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Earth Sciences ; Social Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Social Sciences ; Biology And Life Sciences ; Social Sciences
    E-ISSN: 1932-6203
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  • 5
    Language: English
    In: Sex Roles, 2018, Vol.78(9), pp.625-636
    Description: The present study examined to what extent selection and influence processes for physical aggression and prosociality in friendship networks differed between sex-specific contexts (i.e., all-male, all-female, and mixed-sex classrooms), while controlling for perceived popularity. Whereas selection processes reflect how behaviors shape friendships, influence processes reveal the reversed pattern by indicating how friends affect individual behaviors. Data were derived from a longitudinal sample of early adolescents from Chile. Four all-male classrooms ( n  = 150 male adolescents), four all-female classrooms ( n  = 190 female adolescents), and eight mixed-sex classrooms ( n  = 272 students) were followed one year from grades 5 to 6 ( M age  = 13). Analyses were conducted by means of stochastic-actor-based modeling as implemented in RSIENA. Although it was expected that selection and influence effects for physical aggression and prosociality would vary by context, these effects showed remarkably similar trends across all-male, all-female, and mixed-sex classrooms, with physical aggression reducing and with prosociality increasing the number of nominations received as best friend in all-male and particularly all-female classrooms. Further, perceived popularity increased the number of friendship nominations received in all contexts. Influence processes were only found for perceived popularity, but not for physical aggression and prosociality in any of the three contexts. Together, these findings highlight the importance of both behaviors for friendship selection independent of sex-specific contexts, attenuating the implications of these gendered behaviors for peer relations.
    Keywords: Physical aggression ; Prosociality ; Stochastic-actor based modeling (RSIENA) ; Same-sex/mixed-sex contexts ; Social networks ; Selection ; Influence ; Perceived popularity
    ISSN: 0360-0025
    E-ISSN: 1573-2762
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  • 6
    Language: English
    In: Demography, 2018, Vol.55(4), pp.1547-1565
    Description: Intergenerational mobility has remained stable over recent decades in the United States but varies sharply across the country. In this article, I document that areas with more prevalent slavery by the outbreak of the Civil War exhibit substantially less upward mobility today. I find a negative link between prior slavery and contemporary mobility within states, when controlling for a wide range of historical and contemporary factors including income and inequality, focusing on the historical slave states, using a variety of mobility measures, and when exploiting geographical differences in the suitability for cultivating cotton as an instrument for the prevalence of slavery. As a first step to disentangle the underlying channels of persistence, I examine whether any of the five broad factors highlighted by Chetty et al. (2014a) as the most important correlates of upward mobility—family structure, income inequality, school quality, segregation, and social capital—can account for the link between earlier slavery and current mobility. More fragile family structures in areas where slavery was more prevalent, as reflected in lower marriage rates and a larger share of children living in single-parent households, is seemingly the most relevant to understand why it still shapes the geography of opportunity in the United States.
    Keywords: Intergenerational mobility ; Slavery ; Persistence
    ISSN: 0070-3370
    E-ISSN: 1533-7790
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  • 7
    In: PLoS ONE, 2015, Vol.10(4)
    Description: This paper identifies trends within and relationships between the amount of participation and the quality of contributions in three crowdsourced surveys. Participants were asked to perform a collective problem solving task that lacked any explicit incentive: they were instructed not only to respond to survey questions but also to pose new questions that they thought might-if responded to by others-predict an outcome variable of interest to them. While the three surveys had very different outcome variables, target audiences, methods of advertisement, and lengths of deployment, we found very similar patterns of collective behavior. In particular, we found that: the rate at which participants submitted new survey questions followed a heavy-tailed distribution; the distribution in the types of questions posed was similar; and many users posed non-obvious yet predictive questions. By analyzing responses to questions that contained a built-in range of valid response we found that less than 0.2% of responses lay outside of those ranges, indicating that most participants tend to respond honestly to surveys of this form, even without explicit incentives for honesty. While we did not find a significant relationship between the quantity of participation and the quality of contribution for both response submissions and question submissions, we did find several other more nuanced participant behavior patterns, which did correlate with contribution in one of the three surveys. We conclude that there exists an optimal time for users to pose questions early on in their participation, but only after they have submitted a few responses to other questions. This suggests that future crowdsourced surveys may attract more predictive questions by prompting users to pose new questions at specific times during their participation and limiting question submission at non-optimal times.
    Keywords: Research Article
    E-ISSN: 1932-6203
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  • 8
    In: PLoS ONE, 2015, Vol.10(7)
    Description: Background Mortality from ischemic stroke has declined over time. However, little is known about the reasons for the decreased mortality. We therefore aimed to evaluate trends in in-hospital mortality and to identify factors associated with these trends. Methods This study was based on a prospective database of 26 hospitals of the Stroke Register of Northwestern Germany, which included 73,614 patients admitted between 2000 and 2011. Time trends in observed (crude) and risk-adjusted in-hospital mortality were assessed. Independent factors associated with death after stroke were evaluated using multivariable logistic regression analysis. Results The observed in-hospital mortality decreased from 6.6% in 2000 to 4.6% in 2008 (P 〈 0.001 for trend) and then remained fairly stable. The risk-adjusted mortality decreased from 2.85% in 2000 to 1.86% in 2008 (P 〈 0.01 for trend) and then increased to 2.32% in 2011. Use of in-hospital treatments including antiplatelets within 48 hours, antihypertensive therapy, statins, antidiabetics, physiotherapy and anticoagulants increased over time and was significantly associated with a decrease in mortality. The association of the year of admission with mortality became insignificant after adjustment for antiplatelet therapy within 48 hours (from OR 0.96; 95% CI, 0.94-0.98, to OR 0.99; 95% CI, 0.97-1.01) and physiotherapy (from OR 0.96; 95% CI, 0.94-0.97, to OR 0.99; 95% CI, 0.97-1.00). Conclusions In-hospital mortality decreased by approximately one third between 2000 and 2008. This decline was paralleled by improvements in different in-hospital managements, and we demonstrated that it was partly mediated by early antiplatelet therapy and physiotherapy use.
    Keywords: Research Article
    E-ISSN: 1932-6203
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  • 9
    In: Nature, 2011, Vol.472(7342), p.238
    Description: Superfamily 1 and superfamily 2 RNA helicases are ubiquitous messenger-RNA-protein complex (mRNP) remodelling enzymes that have critical roles in all aspects of RNA metabolism. The superfamily 2 DEAD-box ATPase Dbp5 (human DDX19) functions in mRNA export and is thought to remodel mRNPs at the nuclear pore complex (NPC). Dbp5 is localized to the NPC via an interaction with Nup159 (NUP214 in vertebrates) and is locally activated there by Gle1 together with the small-molecule inositol hexakisphosphate (InsP sub(6)). Local activation of Dbp5 at the NPC by Gle1 is essential for mRNA export in vivo; however, the mechanistic role of Dbp5 in mRNP export is poorly understood and it is not known how Gle1 sub(InsP6) and Nup159 regulate the activity of Dbp5. Here we report, from yeast, structures of Dbp5 in complex with Gle1 sub(InsP6), Nup159/Gle1 sub(InsP6) and RNA. These structures reveal that InsP sub(6) functions as a small-molecule tether for the Gle1-Dbp5 interaction. Surprisingly, the Gle1 sub(InsP6)-Dbp5 complex is structurally similar to another DEAD-box ATPase complex essential for translation initiation, eIF4G-eIF4A, and we demonstrate that Gle1 sub(InsP6) and eIF4G both activate their DEAD-box partner by stimulating RNA release. Furthermore, Gle1 sub(InsP6) relieves Dbp5 autoregulation and cooperates with Nup159 in stabilizing an open Dbp5 intermediate that precludes RNA binding. These findings explain how Gle1 sub(InsP6), Nup159 and Dbp5 collaborate in mRNA export and provide a general mechanism for DEAD-box ATPase regulation by Gle1/eIF4G-like activators.
    Keywords: Adenosinetriphosphatase ; 14830;
    ISSN: 0028-0836
    E-ISSN: 14764687
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  • 10
    Language: English
    In: Environmental Pollution, September 2016, Vol.216, pp.624-635
    Description: Rigorous studies of recovery from soil acidification are rare. Hence, we resampled 97 old-growth beech stands in the Vienna Woods. This study exploits an extensive data set of soil (infiltration zone of stemflow and between trees area at different soil depths) and foliar chemistry from three decades ago. It was hypothesized that declining acidic deposition is reflected in soil and foliar chemistry. Top soil pH within the stemflow area increased significantly by 0.6 units in both H O and KCl extracts from 1984 to 2012. Exchangeable Ca and Mg increased markedly in the stemflow area and to a lower extent in the top soil of the between trees area. Trends of declining base cations in the lower top soil were probably caused by mobilization of organic S and associated leaching with high amounts of sulfate. Contents of C, N and S decreased markedly in the stemflow area from 1984 to 2012, suggesting that mineralization rates of organic matter increased due to more favorable soil conditions. It is concluded that the top soil will continue to recover from acidic deposition. However, in the between trees areas and especially in deeper soil horizons recovery may be highly delayed. The beech trees of the Vienna Woods showed no sign of recovery from acidification although S deposition levels decreased. Release of historic S even increased foliar S contents. Base cation levels in the foliage declined but are still adequate for beech trees. Increasing N/nutrient ratios over time were considered not the result of marginally higher N foliar contents in 2012 but of diminishing nutrient uptake due to the decrease in ion concentration in soil solution. The mean foliar N/P ratio already increased to the alarming value of 31. Further nutritional imbalances will predispose trees to vitality loss.
    Keywords: Fagus Sylvatica ; Long-Term Trend ; Plant Nutrition ; Soil Acidification ; Stemflow ; Engineering ; Environmental Sciences ; Anatomy & Physiology
    ISSN: 0269-7491
    E-ISSN: 1873-6424
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