Sustained synchronized neuronal network activity in a human astrocyte co-culture system

Impaired neuronal network function is a hallmark of neurodevelopmental and neurodegenerative disorders such as autism, schizophrenia, and Alzheimer's disease and is typically studied using genetically modified cellular and animal models. Weak predictive capacity and poor translational value of these models urge for better human derived in vitro models. The implementation of human induced pluripotent stem cells (hiPSCs) allows studying pathologies in differentiated disease-relevant and patient-derived neuronal cells. However, the differentiation process and growth conditions of hiPSC-derived neurons are non-trivial. In order to study neuronal network formation and (mal) function in a fully humanized system, we have established an in vitro co-culture model of hiPSC-derived cortical neurons and human primary astrocytes that recapitulates neuronal network synchronization and connectivity within three to four weeks after final plating. Live cell calcium imaging, electrophysiology and high content image analyses revealed an increased maturation of network functionality and synchronicity over time for co-cultures compared to neuronal monocultures. The cells express GABAergic and glutamatergic markers and respond to inhibitors of both neurotransmitter pathways in a functional assay. The combination of this co-culture model with quantitative imaging of network morphofunction is amenable to high throughput screening for lead discovery and drug optimization for neurological diseases

Beyond seasickness: A motivated call for a new motion sickness standard across motion environments

Motion sickness is known under several names in different domains, such as seasickness, carsickness, cybersickness, and simulator sickness. As we will argue, these can all be considered manifestations of one common underlying mechanism. In recent years, it has received renewed interest, largely due to the advent of automated vehicles and developments in virtual reality, in particular using head-mounted displays. Currently, the most widely accepted standard to predict motion sickness is ISO 2631-1 (1997), which is based on studies on seasickness and has limited applicability to these newer domains. Therefore, this paper argues for extending the ISO standard to cover all forms of motion sickness, to incorporate factors affecting motion sickness, and to consider various degrees of severity of motion sickness rather than just emesis. This requires a dedicated standard, separate from other effects of whole-body vibration as described in the current ISO 2631-1. To that end, we first provide a sketch of the historical origins of the ISO 2631-1 standard regarding motion sickness and discuss the evidence for a common mechanism underlying various forms of motion sickness. After discussing some methodological issues concerning the measurement of motion sickness, we outline the main knowledge gaps that require further research

Impact of agricultural management on soil aggregates and associated organic carbon fractions: analysis of long-term experiments in Europe

Inversion tillage is a commonly applied soil cultivation practice in Europe, which often has been blamed for deteriorating topsoil stability and organic carbon (OC) content. In this study, the potential to reverse these negative effects in the topsoil by alternative agricultural management practices are evaluated in seven long-term experiments (running from 8 to 54 years the moment of sampling) in five European countries (Belgium, Czech Republic, Hungary, Italy and UK). Topsoil samples (0–15 cm) were collected and analysed to evaluate the effects of conservation tillage (reduced and no tillage) and increased organic inputs of different origin (farmyard manure, compost, crop residues) combined with inversion tillage on topsoil stability, soil aggregates and, within these, OC distribution using wet sieving after slaking. Effects from the treatments on the two main components of organic matter, i.e. particulate (POM) and mineral associated (MAOM), were also evaluated using dispersion and size fractionation. Reduced and no-tillage practices, as well as the additions of manure or compost, increased the aggregates mean weight diameter (MWD) (up to 49 % at the Belgian study site) and topsoil OC (up to 51 % at the Belgian study site), as well as the OC corresponding to the different aggregate size fractions. The incorporation of crop residues had a positive impact on the MWD but a less profound effect both on total OC and on OC associated with the different aggregates. A negative relationship between the mass and the OC content of the microaggregates (53–250 µm) was identified in all experiments. There was no effect on the mass of the macroaggregates and the occluded microaggregates (mM) within these macroaggregates, while the corresponding OC contents increased with less tillage and more organic inputs. Inversion tillage led to less POM within the mM, whereas the different organic inputs did not affect it. In all experiments where the total POM increased, the total soil organic carbon (SOC) was also affected positively. We concluded that the negative effects of inversion tillage on topsoil can be mitigated by reducing the tillage intensity or adding organic materials, optimally combined with non-inversion tillage methods.</p

Ermittlung und Entwicklung von Maßnahmen zum „Anstoßen“ nachhaltiger Konsummuster

Im vorliegenden Forschungsvorhaben wird das Potential von Nudges für den Bereich des nachhaltigen Konsums mit Schwerpunkt auf ökologischen Konsum untersucht. Nudges sind politische Instrumente und können als „Anstupser“ verstanden werden, die auf psychologischen und verhaltensökonomi-schen Erkenntnissen beruhen und Verhaltensänderungen bei den Steuerungsadressaten hervorrufen sollen. Im vorliegenden Bericht wird das Konzept zuerst definiert und hergeleitet. Danach werden Nudges in die ökologische Verbraucherpolitik eingeordnet. Anschließend werden in einer systemati-schen Literaturrecherche Anwendungsbeispiele dargestellt. Es folgt eine kriterienbasierte, schrittwei-se Auswahl von Nudges zum Zweck einer tieferen Analyse und potentiellen Anwendung. Selektionskri-terien sind hierbei das Kosten-Nutzen-Verhältnis der Maßnahme, die rechtliche Zulässigkeit in Deutschland, sowie die Akzeptanz bei Verbraucherinnen und Verbrauchern. Die schließlich fünf iden-tifizierten Good Practices entstammen den Konsumbereichen „Bauen und Wohnen“, „Mobilität“ und „Ernährung“. Auf der Grundlage von Diskussionen im Rahmen eines Multi-Stakeholder-Workshops werden diese verfeinert. Abschließend werden konkrete Umsetzungsszenarien vorgeschlagen und Handlungsempfehlungen für die Politik und Forschung abgeleitet

Calibration and validation of the AquaCrop water productivity model for cassava (Manihot esculenta Crantz)

FAO’s water-driven crop growth simulation model, AquaCrop, was calibrated and validated for cassava (Manihot esculenta Crantz). Existing datasets, used in similar published works, were shared covering several years and regions (Colombia, Nigeria and Togo). Different varieties were tested for the case of Colombia and a single variety (TME-419) for Nigeria and Togo. Overall calibrated biomass simulations resulted in an R² of 0.96 and a RMSE of 1.99 tonne DM/ha. As for dry tuber yield estimates, it was not possible to find a single harvest index for the ensembled varieties given their varying characteristics and limited data per variety. However, for the TME-419 variety (Nigeria and Togo) calibrated root tuber simulations yielded and R² of 0.94 and a RMSE of 2.37 tonne DM/ha. A single crop-file was developed for different cassava varieties and agro-ecological regions, which can be applied with confidence to further study cassava related food security, water productivity, improved agronomic practices, etc

Sorghum water use efficiency and yield variations discerned by 13C isotopic technique under managed agricultural practices in Upper Eastern Kenya

Current knowledge on using 13C discrimination as an indirect measure of yield and water use efficiency (WUE) under different soil moisture conditions and soil fertility inputs in C4 crop species has considerable uncertainty. The objective of this study was to test for (i) the effect of selected soil water conservation measures and soil fertility inputs on sorghum yield, water use efficiency, and 13C discrimination, (ii) evaluate the relationship between various measures of water use efficiency and 13C discrimination, between sorghum yield and 13C discrimination; (iii) sorghum stem diameter and WUE and, the use of stem diameter and 13C discrimination as potential yield and WUE proxy. We implemented a field trial on-station for five seasons in the semi-arid areas of Upper Eastern Kenya. The experiment was designed in a randomized complete block design (RCBD) with three levels of nitrogen fertilization (120 kg ha−1, 60 kg ha−1, and 30 kg ha−1) application with four replications. The selected soil water conservation measures and soil fertility management were minimum tillage, mulching, tied ridging, and Managing Beneficial Interactions in Legume Intercrops (MBILI) along a control (no input). Water use efficiency was determined using carbon discrimination analysis and gravimetric technique. The leaves and post-harvest grain samples were analyzed for %N, %C, and δ13C on an Isotope Ratio Mass Spectrometer (IRMS). A clear and significant (p≤ 0.05) treatment effect was observed on the 13C isotopic discrimination and sorghum yield and growth attributes over the five seasons. The highest (4.85 Mg ha-1) grain yield was observed with minimum tillage with crop residue treatment. The δ13C values ranged from -13.14to -11.86‰for the sorghum grain. Treatments under minimum tillage with residue and tied ridges and the MBILI intercrop had significantly (p≤ 0.05) higher sorghum grain yield, WUE, stem diameter, chlorophyll content, and high δ13C values. The 13C discrimination was significantly (p≤ 0.05) associated with yield, WUE, stem diameter, and leaf chlorophyll. In the treatment with high N rate, the equation relating 13C discrimination to yield was Yield (Mg ha-1) = 1.4822δ13C + 20.879; R² = 0.3518. A significant positive relationship (R2 = 0.31) was observed between grain N fertilizer use efficiency and grain δ13C in sorghum harvested from plots with high N rate treatments. There was also a correlation (R2 = 0.341; p=0.001) between WUE and sorghum stem diameter. Based on these results, we conclude that grain 13C discrimination values at maturity and stem diameter are a potential complementary criterion for assessing sorghum yield performance and WUE under different soil moisture and nutrient availability conditions. Therefore, it can be deduced that minimum tillage with crop residue with a high fertilizer application rate (120N/ha) improves sorghum grain yield, WUE, and higher grain δ13C values. The high grain δ13C values observed with minimum tillage with crop residue over the five seasons indicate that plants suffered less water stress under minimum tillage with crop residue treatment. Therefore, grain δ13C discrimination and stem diameter can be used as water use efficiency proxy with C4 crops like sorghum

Can we use Electrical Resistivity Tomography to measure root zone moisture dynamics in fields with multiple crops?

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