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ABSTRACTWe present an analysis of the performance data of a monitored PV system onboard a light commercial electric vehicle during parking and driving conditions in the Hannover region of Germany. The PV system's nominal power is 2180 WP with flat silicon modules on the vehicle's roof, rear, left, and right sides and other electronic components needed to charge the vehicle's high‐voltage (HV) battery. The analysis indicated that after 488.92 h of operation, the modules mounted on the vehicle roof produced 133.32 kWh of electricity during parking at the best possible orientation compared to 15.4, 30.67, and 22.99 kWh for the modules mounted on the rear, left, and right sides, respectively. During the trips, after 31.99 h of operation, 6.12, 0.68, 1.08, and 1.86 kWh of electricity were produced by the modules on the roof, rear, left, and right sides, respectively. The overall system efficiency was in the 60%–65% range. The aggregated usable electricity reaching the HV battery after multiple conversion stages generated by the system at the two parking locations was 129.39 kWh. PV electricity generated at the two parking locations enabled a range extension of approximately 530 km, which is 30% of the total distance driven during the measurement period between April and July 2021.

Periglacial alluvial fans are common in northwestern and central Europe and their pre-Holocene stratigraphic records typically date back to late Middle Pleniglacial and Late Pleniglacial (late MIS3 and 2). Preserved stratigraphic records that include an entire interglacial-glacial cycle have, so far, not been described and it is thus unknown how periglacial alluvial fans responded during a full cycle of interglacial-glacial climate changes. In this paper, we reconstruct the evolution of the Eerbeek periglacial alluvial fan in the Netherlands which was deposited during the late Saalian (MIS 6) to late Weichselian (MIS 2) period, including the entire last interglacial–glacial cycle (MIS 5-2). Our reconstruction is based on 48, up-to 45-m deep borehole and Cone Penetration Test (CPT) logs that allowed the construction of an 8-km long longitudinal and a 7-km long transverse cross section over the Eerbeek periglacial alluvial fan. Age control was provided by means of 17, previously published, Optically Stimulated Luminescence ages of two boreholes on the fan, and 14 14C ages from three boreholes and a nearby, now abandoned, quarry.Overlying a thick, late Saalian (MIS 6) alluvial fan record, is a 4- to 18-m thick alternation of distinct organic (mainly peat and humic clays), siliciclastic alluvial fan (coarse- and medium-grained sands), Rhine (coarse- and medium grained sands), and aeolian (mainly medium-grained sands) stratigraphic units. Organic levels indicate fan stability during the Eemian interglacial (MIS 5e), and Brørup (MIS 5c), Odderade–Ognon interstadial complex (MIS 5a), and Middle Pleniglacial (MIS 3) interstadials 14, 13, 12 and 11 as well as late MIS 2 interstadial 1a. Clastic sediments indicate alluvial fan activity during the Herning (MIS 5d), Rederstall (MIS 5b), Ognon stadial complex (late MIS 5a), Early Pleniglacial (MIS 4) and upper Middle Pleniglacial (upper MIS 3) stadials 13, 12 and 11. Sediments from the coldest and driest period of the Last Glacial (late MIS 3 and MIS 2) are absent and following a phase of aeolian activity, the fan was only reactivated at the MIS 2 to MIS 1 transition (stadial 1). We attribute the absence of fan activity during the coldest period of the last interglacial-glacial cycle to the eastward orientation of the fan making it less sensitive to permafrost melt.The colder MIS substages and stadials in which the Eerbeek fan was active coincided with the presence of permafrost and/or a seasonal, deeply frozen soil, and a relatively humid climate during which vegetation was largely absent. The presence of channels that dissect the underlying organic units suggests that the Eerbeek fan initially responded to the changes from interstadials to stadials by means of erosion. As climate cooled and permafrost/deep frost developed, the fan switched to alluvial aggradation. The consistent presence of coarsening-fining upward sequences suggests a relation with cycles of increased overland flow due to increasingly more frozen subsoil conditions. The fan stratigraphy therefore shows the direct coupling between warmer-colder MIS substages and interstadial-stadial climate cyclicity and alluvial fan response over the entire last interglacial-glacial cycle.

Abstract Wood density is a critical control on tree biomass, so poor understanding of its spatial variation can lead to large and systematic errors in forest biomass estimates and carbon maps. The need to understand how and why wood density varies is especially critical in tropical America where forests have exceptional species diversity and spatial turnover in composition. As tree identity and forest composition are challenging to estimate remotely, ground surveys are essential to know the wood density of trees, whether measured directly or inferred from their identity. Here, we assemble an extensive dataset of variation in wood density across the most forested and tree-diverse continent, examine how it relates to spatial and environmental variables, and use these relationships to predict spatial variation in wood density over tropical and sub-tropical South America. Our analysis refines previously identified east-west Amazon gradients in wood density, improves them by revealing fine-scale variation, and extends predictions into Andean, dry, and Atlantic forests. The results halve biomass prediction errors compared to a naïve scenario with no knowledge of spatial variation in wood density. Our findings will help improve remote sensing-based estimates of aboveground biomass carbon stocks across tropical South America.

ABSTRACTDitches and canals are omitted from global budgets of inland water emissions, despite research showing them to be emitters of greenhouse gases (GHGs). Here, we synthesize data across climate zones and land use types to show, for the first time, that global ditches emit notable amounts of carbon dioxide (CO2) and nitrous oxide (N2O). Ditches had higher per‐area emissions of CO2 and N2O than ponds, lakes, and reservoirs, likely due to high nutrient inputs. Preliminary upscaling showed that the inclusion of ditches would increase global inland water CO2 emissions by 0.6%–1% and N2O emissions by 3%–9%. Trophic state and climate influenced N2O emissions, while CO2 emissions had complex drivers difficult to disentangle at the global scale. This research highlights the importance of including ditches in global inland water GHG budgets and informs more accurate reporting of anthropogenic emissions in national inventories.

BACKGROUND AND PURPOSE: Understanding the cellular and molecular effect of proton radiation, particularly the increased DNA damage complexity at the distal end of the Bragg curve, is current topic of investigation. This work aims to study in vitro clonogenic survival and DNA damage foci kinetics of a head and neck squamous cell carcinoma cell line at various positions along a double passively scattered Bragg curve. Complementary in silico studies are conducted to gain insights into the link between cell survival variations, experimentally yielded foci and the number and complexity of double strand breaks (DSBs). MATERIALS AND METHODS: Proton irradiations are performed at the HollandPTC R&D proton beamline, using a double passively scattered setup. A custom water phantom setup is employed to accurately position the samples within the Bragg curve. FaDu cells are irradiated at the proximal 36 % point of the Bragg peak, (P36), proximal 80 % point of the Bragg peak (P80) and distal 20 % point of the Bragg peak (D20), with dose-averaged mean lineal energies ([Formula: see text]) of 1.10 keV/μm, 1.80 keV/μm and 7.25 keV/μm, respectively. RESULTS: Clonogenic survival correlates strongly with [Formula: see text] , showing similar survival for P36 (D(37%)=3.0 Gy) and P80 (D(37%)=2.9 Gy), but decreased survival for D20 (D(37%) = 1.6 Gy). D20 irradiated samples exhibit increased 53BP1 foci shortly after irradiation, slower resolution of the foci, and larger residual 53BP1 foci after 24 h, indicating unrepaired complex breaks. These experimental observations are supported by the in silico study which demonstrates that irradiation at D20 leads to a 1.7-fold increase in complex DSBs with respect to the total number of strand breaks compared to P36 and P80. CONCLUSIONS: This combined approach provides valuable insights into the cellular and molecular effect of proton radiation, emphasizing the increased DNA damage complexity at the distal end of the Bragg curve, and has the potential to enhance the efficacy of proton therapy.

The present study develops a data-based compact model for the prediction of the fluid temperature evolution in district heating-and-cooling pipeline networks. This model is based on an existing "reduced-order model" by the authors obtained from reduction of the "full-order model" describingthe spatio-temporal energy balance for each pipe segment to a semi-analytical input-output relation between the pipe outlet temperature and the pipe inlet and ground temperatures. The proposed model (denoted XROM) expands on the original reduced-order model by incorporating variable mass flux as an additional input and thus greatly increases its practical relevance. The XROM represents variable mass flux by step-wise switching between mass-flux levels and thereby induces a prediction error relative to the true full-order model evolution after each switching. Theoretical analysis rigorously demonstrates that this error always decays and the XROM invariably converges on the full-order model evolution and, consequently, affords the same predictionaccuracy. Performance analyses reveal that prediction errors are restricted to short "convergence intervals" after each mass-flux switching and the XROM therefore can handle substantially faster operating schemes than the current ones based on hourly monitoring and control. Convergence intervals of O(minutes) are namely typically sufficient - and thus switching frequencies up toO(minutes^-1) permissible during dynamic operation and control actions - for reliable predictions. Quantification of these convergence intervals by an easy-to-use empirical relation furthermore enables a priori determination of the conditions for reliable predictions. Moreover, the XROM can capture the full 3D system dynamics (provided incompressible flow and heat-transfer mechanismsdepending linearly on temperature) versus the essentially 1D approximation of current compact pipe models yet at similar computational cost. These attributes advance (parts of) district heating and cooling networks demanding prediction accuracies beyond 1D as its primary application area. This makes the XROM complementary to said pipe models and thereby expands the modellingcapabilities for handling the growing complexity of (next-generation) networks.

Anion exchange membrane fuel cells (AEMFCs) have emerged as a promising alternative to commercialized proton exchange membrane fuel cells because they can enable much lower costs by using cheaper materials, especially non-precious metal electrocatalysts. However, the commercialization of AEMFCs faces several technical challenges, including water management during operation. More specifically, achieving high power density typically requires AEMFCs to be operated with anode/cathode reacting gas dew points much lower than the cell operating temperature to prevent flooding. Conversely, achieving long lifetime typically requires reacting gases with high relative humidities to be supplied to the cell. A solution is needed that can allow for high power density to be achieved under states of high hydration – i.e., high reacting gas dew points, even at lower operating temperatures (e.g., 60 °C). This work explores multiple electrode-level water management strategies for AEMFCs with the goal of enabling high power operation at high states of hydration, including: i) hydrophobic catalyst layers by adding PTFE; ii) hydrophilic catalyst layers by adding Nafion®; iii) gas diffusion layers (GDLs) with patterned wettability; and iv) combinations thereof. Compared to hydrophobic electrodes suffering serious flooding at high hydration states, the promising result of this work is one of the highest reported peak power densities reported to date at 60 oC, 1.5 W cm-2, under H2/O2 flow with hydrophilic-hydrophobic hybrid electrodes, even with anode and cathode dew points of 59 °C and 62 °C, respectively. It is expected that these electrode-level water management strategies can contribute to the commercialization of AEMFCs in the near future.