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Optimization for automatic whole brain volumetry An MPRAGE image contrast study of a 12- and 32 channel head coil at 3T
Introduction: Regional and global brain volumes are of great interest in many different research projects, not least in Alzheimer’s research. The purpose of this project is to optimize the MPRAGE sequence for automatic and repeatable segmentation of human brain tissue. The volume is calculated for the whole brain, white matter (WM), grey matter (GM) and cerebrospinal fluid (CSF). Materials and met
Biologi: Sinnesbiologi
Matematik: Introduktion till högre analys
Numerisk analys: Grundkurs
Violent conflict and taxation : Micro-level evidence from Burkina Faso
This study analyzes how violent conflict influences taxation in a poor, conflict-affected country, Burkina Faso. We use a unique, large, and representative panel dataset on tax collection of firms between 2015 and 2022 and geographically match these data with indicators of violent conflict at the municipal level. We find that firms pay a lower amount of tax in areas affected by violence. We also f
Dendrochronology with a medical X-ray photon counting computed tomography scanner
Dendrochronology traditionally involves invasive techniques that might harm cultural heritage artifacts. Non-invasive approaches using X-ray technology and computed tomography (CT) have emerged, but dedicated CT systems are limited in availability. This study explored the viability of using a recently developed photon counting medical CT scanner for growth ring analysis. Six wood samples from pine
Correlations in species richness between taxa depend on habitat, scale and landscape context
Biodiversity indicators are assumed to reflect changes in e.g. species richness of multiple taxa, but correlations in species richness between taxa have often been shown to be weak. However, only few studies are based on data allowing for rigorous tests whether strengths of correlations differ between habitat and landscape factors. We compared strengths of correlations between species richness of
Landscape context affects the relationship between local and landscape species richness of butterflies in semi-natural habitats
Local species richness of butterflies can be expected to benefit from both local habitat properties as well as the availability of suitable habitats and source populations in the surrounding landscape. Whether local species richness is dependent on local or landscape factors can be assessed by examining the relationship between local and landscape species richness. Here we studied how local specie
Ecosystem Service Valuation for National Accounting : A Reply to Obst, Hein and Edens (2016)
While recent experimental frameworks for national ecosystem service accounting have shown substantial progress, in our view some crucial methodological issues remain that deserve further consideration before setting final standards. In response to the landmark work of Obst et al. (Environ Resour Econ 64:1–23, 2016. doi: 10.1007/s10640-015-9921-1), we provide arguments with regard to the suitabilit
A framework to explore the effects of urban planning decisions on regulating ecosystem services in cities
Urban planning is the most relevant decision-making process affecting urban regulating ecosystem services. However, a clear understanding of the effects of planning decisions on both the supply and demand of urban regulating ecosystem services is still lacking. To support planners in enhancing urban regulating ecosystem services, there is a need to understand what variables are at stake and how ch
Is urban spatial development on the right track? Comparing strategies and trends in the European Union
Urban spatial development is a crucial issue for spatial planning and urban governance, ultimately determining cities’ sustainability. While a set of spatial strategies to address urban development are progressively gaining international consensus, their actual applicability is still contested. An interesting test-bed is represented by the European Union (EU), where common spatial strategies have
Improving the predictability of global CO2 assimilation rates under climate change
Feedbacks between the terrestrial carbon cycle and the atmosphere have the potential to greatly modify expected rates of future climate change. This makes it all the more urgent to exploit all existing data for the purpose of accurate modelling of the underlying processes. Here we use a Bayesian random sampling method to constrain parameters of the Farquhar model of leaf photosynthesis and a model
Terrestrial organic matter support of lake food webs : evidence from lake metabolism and stable hydrogen isotopes of consumers
We quantified the utilization of terrestrial organic matter (OM) in the food web of a humic lake by analyzing the metabolism and the consumers' stable isotopic (C, H, N) composition in benthic and pelagic habitats. Terrestrial OM inputs (3 g C m(-2) d(-1)) to the lake greatly exceeded autochthonous OM production (3 mg C m(-2) d(-1)) in the lake. Heterotrophic bacterial growth (19 mg C m(-2) d(-1))
On the capability of Monte Carlo and adjoint inversion techniques to derive posterior parameter uncertainties in terrestrial ecosystem models
Terrestrial ecosystem models (TEMs) contain the coupling of many biogeochemical processes with a large number of parameters involved. In many cases those parameters are highly uncertain. In order to reduce those uncertainties, parameter estimation methods can be applied, which allow the model to be constrained against observations. We compare the performance and results of two such parameter estim
The productivity, metabolism and carbon cycle of two lowland tropical forest plots in south-western Amazonia, Peru
Background: The forests of western Amazonia are known to be more dynamic that the better-studied forests of eastern Amazonia, but there has been no comprehensive description of the carbon cycle of a western Amazonian forest. Aims: We present the carbon budget of two forest plots in Tambopata in south-eastern Peru, western Amazonia. In particular, we present, for the first time, the seasonal variat
Ecosystem productivity and carbon cycling in intact and annually burnt forest at the dry southern limit of the Amazon rainforest (Mato Grosso, Brazil)
Background: The impact of fire on carbon cycling in tropical forests is potentially large, but remains poorly quantified, particularly in the locality of the transition forests that mark the boundaries between humid forests and savannas. Aims: To present the first comprehensive description of the impact of repeated low intensity, understorey fire on carbon cycling in a semi-deciduous, seasonally d
Productivity and carbon allocation in a tropical montane cloud forest in the Peruvian Andes
Background: The slopes of the eastern Andes harbour some of the highest biodiversity on Earth and a high proportion of endemic species. However, there have been only a few and limited descriptions of carbon budgets in tropical montane forest regions. Aims: We present the first comprehensive data on the production, allocation and cycling of carbon for two high elevation (ca. 3000 m) tropical montan
Understanding quantitative structure-property relationships uncertainty in environmental fate modeling
In cases in which experimental data on chemical-specific input parameters are lacking, chemical regulations allow the use of alternatives to testing, such as in silico predictions based on quantitative structureproperty relationships (QSPRs). Such predictions are often given as point estimates; however, little is known about the extent to which uncertainties associated with QSPR predictions contri
Distinct patterns of microbial metabolism associated to riverine dissolved organic carbon of different source and quality
Dissolved organic carbon (DOC) in rivers contains a wide range of molecules that can be assimilated by microbes. However, there is today no integrated understanding of how the source and composition of this DOC regulate the extent to which the DOC can support microbial growth and respiration. We analyzed patterns in microbial metabolism of DOC from different streams and rivers in Québec, by combin
