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Post-fire effects on dissolved organic carbon concentrations in freshwater streams: a meta-analysis
No full textWildfires alter hydrology and carbon export, yet the reported stream dissolved organic carbon (DOC) responses vary in magnitude and persistence. We conducted a meta-analysis of the peer-reviewed literature to assess wildfire effects on peak flow DOC concentrations in forested catchments (k = 52 effect sizes). A multi-level model showed a mean DOC increase of 26 % (95 % CI: 15–38 %), peaking in the second post-fire year (23 %) and attenuation thereafter. Responses varied with catchment and fire attributes. Small catchments (≤10 km2) showed the largest increases. Humid continental climates exhibited strong increases, whereas subarctic sites tended to decline. Conifer-dominated forests increased more than mixed forests. Loam and clay loam soils showed substantial increases, sandy loam smaller but positive changes, and silt loam decreases. High and moderate severity, larger burned extent (10–50 % and >50 %), and short (30 days) fire durations amplified early responses. Non-permafrost regions showed increases during the first years after fire.
Two main mechanisms align with these patterns. Post-fire hydrology shifts reduce interception and infiltration while increasing near-surface runoff and enhancing hillslope-channel connectivity. Fire supplies labile residues that leach during storms. Event studies frequently report rising-limb enrichment and more chemodynamic behavior, which aligns with these mechanisms. Understanding DOC trajectories after fire informs ecosystem recovery, carbon budgets, and drinking-water treatment risk. Key gaps include the scarce discharge-resolved chemistry and a geographic skew toward North America. We recommend paired DOC-discharge sampling and standardized reporting to improve prediction of post-fire DOC export
The role of non-verbal auditory and visual short-term memory for serial order in predicting later spoken language in children with Developmental Language Disorder
No full textFather's experiences of the effects of using family leave on their careers and agency as a family man and employee
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Spatial and temporal modulation in time-domain diffuse optical tomography
No full textDiffuse optical tomography (DOT) utilizes visible and near-infrared light to non-invasively study biological structures and functions, such as imaging breast cancer and brain activity. Time-domain DOT systems use pulsed light and measure the time-varying temporal point spread function. Time-domain DOT provides information from both superficial and deep tissue, and thus it is regarded as a technique that provides the richest information, among other measurement types in DOT, such as continuous-wave and intensity-modulated DOT. However, modeling and image reconstruction of time-domain data as such is computationally expensive. To overcome this problem, different transformations of data types in DOT have been utilized with an aim to compress the data while maintaining the rich information content. Furthermore, different structural illuminations have been utilized in DOT to enhance the imaging modality. In this work, we study the use of temporal and spatial modulation in time-domain DOT using numerical simulations. For temporal modulation, a truncated Fourier-series approximation is utilized and the use of different numbers of frequencies is studied. Furthermore, structural illumination and detection are implemented using Hadamard patterns. The use of different numbers and different complexities of patterns is studied. The simulations show that the resolution and contrast of reconstructed absorption and scattering images can be improved by increasing the number of Fourier frequencies and the number of Hadamard patterns in the data. However, it was also noticed that, after a certain level of improvement, including more frequencies and Hadamard patterns do not change reconstructed images significantly
Untargeted metabolomics for in vitro characterization of transpoter-targeted prodrugs. A comparative evaluation of Mass Spectrometry and Nuclear Magnetic Resonance approaches in assessing efficacy and toxicity
No full textStoichiometric transport of estrone 3-sulfate among genetic variants of OATP1A2 and OATP2B1 and structural analysis by molecular dynamics simulation: Impairment of gating mechanism in the unstable inward-open conformation of OATP2B1 (Asp215Val) significantly suppress the transport activity
No full textThis study investigated the impact of genetic variations in organic anion transporting polypeptides (OATPs) 1A2 and 2B1 on their transport activity at pH 6.3 and 7.4 by using HEK293 cells expressing OATP variants, focusing on stoichiometric transport kinetic parameters corrected for the number of transporters on the plasma membrane. In the OATP2B1 Asp215Val, the maximal velocity per OATP molecule and intrinsic clearance at pH 6.3 were drastically reduced to 0.0648- and 0.0178-fold, respectively, compared with the wild type. All tested OATP1A2 variants exhibited increased transport activity at pH 6.3, suggesting that OATP1A2 is more sensitive to extracellular pH. Furthermore, we used the AlphaFold model to explain the observed differences in transport activity among genetic variants. In OATP1A2, the Glu172Asp mutation replaces a longer glutamate side chain with a shorter aspartate, which may enhance substrate interactions while weakening the salt-bridge interactions with neighboring residues, potentially compromising structural integrity. In OATP2B1, the Asp215Val variant was found to disrupt a key salt-bridge interaction with Lys595, which destabilizes the outward-open conformation. Moreover, the Val201Met mutation appears to lock the transporter in a single conformational state. Our findings underscore the importance of transmembrane helix 4 in maintaining functional conformational dynamics and suggest that mutations in this region can significantly alter substrate binding and transport efficiency in OATP1A2 and 2B1
