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The proportion of individuals that are found to have empty stomachs during a survey of a predator population's diet has been used as an indicator of the average individual's state of energy balance and of the degree to which its feeding rate (i.e., its functional response) is saturated with respect to prey availability. As such, the proportion of empty stomachs provides insights into the effects of prey on predators and vice v...
The number of studies investigating root length has increased, particularly in the context of root length measurements observed through windows such as minirhizotrons and rhizoboxes. However, there are currently two obstacles constraining their broader utility: (1) the absence of standardized terminology or units for root length data, and (2) the translation from two-dimensional (2D) to three-dimensional (3D) data. Here, we de...
Background and aims Plants store carbohydrates for later use during, e.g., night, drought, and recovery after stress. Carbon allocation presents the plant with tradeoffs, notably between growth and storage. We asked how this tradeoff works for cassava ( Manihot esculenta) pre- and post-storage root (SR) formation and if manipulation of the number of storage organs and leaf growth rate might increase yield. Methods We developed...
Shallow roots of different crops have greater water uptake rates per unit length than deep roots in well-watered soilNARA Subscribed
Purpose Commonly, root length distributions are used as a first approximation of root water uptake profiles. In this study we want to test the underlying hypothesis of a constant water uptake rate per unit root length over depth. Methods Root water uptake profiles were measured using a novel sensor technology. Root length was measured with MRI and by scanning harvested roots. Experiments were performed with pot-grown barley (...
Background The rhizosphere is the influence-sphere of the root. It is a local ecosystem with complex functions that determine nutrient uptake, cycling of resources, and plant health. Mathematical models can quantitatively explain and help to understand rhizosphere complexity. To interpret model predictions and relevance of processes, we require understanding of the underlying concepts. Conceptualization of rhizosphere processe...
Phenotypic response to soil compaction varies among genotypes and correlates with plant size in sorghumNARA Subscribed
Aims Soil compaction is a major yield-reducing factor worldwide and imposes physico-chemical constraints to plant growth and development. Facing limitations, roots can adapt and compensate for loss of functioning through their plasticity. Being primarily a belowground challenge, tolerance to soil compaction needs to be associated with root phenotype and plasticity. It is therefore of importance to distinguish between size-rela...
To investigate whether blood–brain barrier (BBB) disruption is a potential mechanism of usual age-related cognitive decline, we conducted dynamic contrast–enhanced (DCE) MRI to measure BBB leakage in a healthy sample, and investigated the association with longitudinal cognitive decline. In a sample of neurologically and cognitively healthy, older individuals, BBB leakage rate in the white and grey matter and hippocampus was me...
Blood–brain barrier (BBB) breakdown can disrupt nutrient supply and waste removal, which affects neuronal functioning. Currently, dynamic contrast-enhanced (DCE) MRI is the preferred in-vivo method to quantify BBB leakage. Dedicated DCE MRI studies in normal aging individuals are lacking, which could hamper value estimation and interpretation of leakage rate in pathological conditions. Therefore, we applied DCE MRI to investig...
EPMA-World Congress 2015NARA Subscribed