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| 2. |
- Reischer, G. H., et al.
(författare)
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Performance Characteristics of qPCR Assays Targeting Human- and Ruminant-Associated Bacteroidetes for Microbial Source Tracking across Sixteen Countries on Six Continents
- 2013
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Ingår i: Environmental Science & Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:15, s. 8548-8556
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Tidskriftsartikel (refereegranskat)abstract
- Numerous quantitative PCR assays for microbial fecal source tracking (MST) have been developed and evaluated in recent years. Widespread application has been hindered by a lack of knowledge regarding the geographical stability and hence applicability of such methods beyond the regional level. This study assessed the performance of five previously reported quantitative PCR assays targeting human-, cattle-, or ruminant-associated Bacteroidetes populations on 280 human and animal fecal samples from 16 countries across six continents. The tested cattle-associated markers were shown to be ruminant-associated. The quantitative distributions of marker concentrations in target and nontarget samples proved to be essential for the assessment of assay performance and were used to establish a new metric for quantitative source-specificity. In general, this study demonstrates that stable target populations required for marker-based MST occur around the globe. Ruminant-associated marker concentrations were strongly correlated with total intestinal Bacteroidetes populations and with each other, indicating that the detected ruminant-associated populations seem to be part of the intestinal core microbiome of ruminants worldwide. Consequently tested ruminant-targeted assays appear to be suitable quantitative MST tools beyond the regional level while the targeted human-associated populations seem to be less prevalent and stable, suggesting potential for improvements in human-targeted methods.
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| 3. |
- Wohlfahrt, G., et al.
(författare)
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An ecosystem-scale perspective of the net land methanol flux : synthesis of micrometeorological flux measurements
- 2015
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7324. ; 15:13, s. 7413-7427
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Tidskriftsartikel (refereegranskat)abstract
- Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates, reflecting uncertainties in the approaches used to model and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land-atmosphere methanol exchange. Our study shows that the controls of plant growth on production, and thus the methanol emission magnitude, as well as stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; however, they are neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow for full advantage to be taken of the rich information content of micrometeorological flux measurements.
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| 5. |
- Mollenhauer, B., et al.
(författare)
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Validation of Serum Neurofilament Light Chain as a Biomarker of Parkinson's Disease Progression
- 2020
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Ingår i: Movement Disorders. - : Wiley. - 0885-3185 .- 1531-8257. ; 35:11, s. 1999-2008
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Tidskriftsartikel (refereegranskat)abstract
- Background The objective of this study was to assess neurofilament light chain as a Parkinson's disease biomarker. Methods We quantified neurofilament light chain in 2 independent cohorts: (1) longitudinal cerebrospinal fluid samples from the longitudinal de novo Parkinson's disease cohort and (2) a large longitudinal cohort with serum samples from Parkinson's disease, other cognate/neurodegenerative disorders, healthy controls, prodromal conditions, and mutation carriers. Results In the Parkinson's Progression Marker Initiative cohort, mean baseline serum neurofilament light chain was higher in Parkinson's disease patients (13 +/- 7.2 pg/mL) than in controls (12 +/- 6.7 pg/mL),P= 0.0336. Serum neurofilament light chain increased longitudinally in Parkinson's disease patients versus controls (P< 0.01). Motor scores were positively associated with neurofilament light chain, whereas some cognitive scores showed a negative association. Conclusions Neurofilament light chain in serum samples is increased in Parkinson's disease patients versus healthy controls, increases over time and with age, and correlates with clinical measures of Parkinson's disease severity. Although the specificity of neurofilament light chain for Parkinson's disease is low, it is the first blood-based biomarker candidate that could support disease stratification of Parkinson's disease versus other cognate/neurodegenerative disorders, track clinical progression, and possibly assess responsiveness to neuroprotective treatments. However, use of neurofilament light chain as a biomarker of response to neuroprotective interventions remains to be assessed. (c) 2020 The Authors.Movement Disorderspublished by Wiley Periodicals LLC. on behalf of International Parkinson and Movement Disorder Society.
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| 6. |
- Bengtsson, G. J, et al.
(författare)
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Determination of Radiative Lifetimes In Neutral Nitrogen Using Short Laser-pulses From A Distributed Feedback Dye-laser
- 1991
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Ingår i: Zeitschrift für Physik D Atoms, Molecules and Clusters. - 0178-7683. ; 22:1, s. 397-399
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Tidskriftsartikel (refereegranskat)abstract
- Radiative lifetimes were determined for two short-lived states in neutral nitrogen. Following photodissociation and two-photon excitation employing the same UV source, excitation to higher states was performed with a distributed feedback dye laser (DFDL). The lifetimes were found to be tau(2p2 4d4D7/2) = 17(3) ns and tau(2p2 5s4P5/2) = 22(3) ns.
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