23 research outputs found
Can Urban Air Mobility become reality? Opportunities, challenges and selected research results
Urban Air Mobility (UAM) is a new air transportation system for passengers
and cargo in urban environments, enabled by new technologies and integrated
into multimodal transportation systems. The vision of UAM comprises the mass
use in urban and suburban environments, complementing existing transportation
systems and contributing to the decarbonization of the transport sector.
Initial attempts to create a market for urban air transportation in the last
century failed due to lack of profitability and community acceptance.
Technological advances in numerous fields over the past few decades have led to
a renewed interest in urban air transportation. UAM is expected to benefit
users and to also have a positive impact on the economy by creating new markets
and employment opportunities for manufacturing and operation of UAM vehicles
and the construction of related ground infrastructure. However, there are also
concerns about noise, safety and security, privacy and environmental impacts.
Therefore, the UAM system needs to be designed carefully to become safe,
affordable, accessible, environmentally friendly, economically viable and thus
sustainable. This paper provides an overview of selected key research topics
related to UAM and how the German Aerospace Center (DLR) contributed to this
research in the project "HorizonUAM - Urban Air Mobility Research at the German
Aerospace Center (DLR)". Selected research results that support the realization
of the UAM vision are briefly presented.Comment: 20 pages, 7 figures, project HorizonUA
Global maps of soil temperature
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0â5 and 5â15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world\u27s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (â0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications
Global maps of soil temperature
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-kmÂČ resolution for 0â5 and 5â15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-kmÂČ pixels (summarized from 8500 unique temperature sensors) across all the worldâs major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications
Global maps of soil temperature.
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications
Entwurf einer Bodenkontrollstation zur Planung und Ăberwachung von Reichweite und Mission unbemannter FluggerĂ€te
Diese Arbeit stellt einen erarbeiteten Ablauf des Ecological Interface Design (EID) vor und ein Konzept fĂŒr die Darstellung von Anzeigen der Kontrollstation einer Drohne. Sie zeigt eine Möglichkeit des Ecological Interface Designs
und fĂŒhrt den Entwurf anhand dieser Methode exemplarisch durch. Dabei werden die HintergrĂŒnde kurz beleuchtet und zusĂ€tzliche Punkte, die BerĂŒcksichtigung finden sollten, ermittelt
CYP26A1-specific antagonist influence on embryonic implantation, gene expression and endogenous retinoid concentration in rats
Identification of Anterior Large Vessel Occlusion Stroke During the Emergency Call: Protocol for a Controlled, Nonrandomized Trial
BackgroundEndovascular thrombectomy (ET), combined with intravenous thrombolysis if possible, is an effective treatment option for patients with stroke who have confirmed anterior large vessel occlusion (aLVO). However, ET is mainly limited to comprehensive stroke centers (CSCs), resulting in a lack of ET capacity in remote, sparsely populated areas. Most stroke networks use the âDrip and Shipâ or âMothershipâ strategy, resulting in either delayed ET or intravenous thrombolysis, respectively.
ObjectiveThis study protocol introduces the Leitstellen-Basierte Erkennung von Schlaganfall-Patienten fĂŒr eine Thrombektomie und daraufhin abgestimmte Optimierung der Rettungskette (LESTOR) strategy, developed to optimize the preclinical part of the stroke chain of survival to improve the clinical outcome of patients with suspected aLVO stroke. This involves refining the dispatch strategy for identifying patients with acute aLVO stroke using a phone-based aLVO query. This includes dispatching emergency physicians and emergency medical services (EMS) to urban emergency sites, as well as dispatching helicopter EMS to remote areas. If a highly suspected aLVO is identified after a standardized aLVO score evaluation during a structured examination at the emergency scene, prompt transport to a CSC should be prioritized.
MethodsThe LESTOR study is a controlled, nonrandomized study implementing the LESTOR strategy, with a stepped-wedge, cluster trial design in 6 districts in southwest Germany. In an interprofessional, iterative approach, an aLVO query or dispatch protocol intended for use by dispatchers, followed by a coordinated aLVO examination score for use by EMS, is being developed, evaluated, and pretested in a simulation study. After the training of all participating health care professionals with the corresponding final aLVO query, the LESTOR strategy is being implemented stepwise. Patients otherwise receive usual stroke care in both the control and intervention groups. The primary outcome is the modified Rankin Scale at 90 days in patients with stroke receiving endovascular treatment. We will use a generalized linear mixed model for data analysis. This study is accompanied by a cost-effectiveness analysis and a qualitative process evaluation.
ResultsThis paper describes and discusses the protocol for this controlled, nonrandomized LESTOR study. Enrollment was completed in June 2023. Data analysis is ongoing and the first results are expected to be submitted for publication in 2024. The project started in April 2020 and will end in February 2024.
ConclusionsWe expect that the intervention will improve the clinical outcome of patients with aLVO stroke, especially outside the catchment areas of CSCs. The results of the accompanying process evaluation and the cost-effectiveness analysis will provide further insights into the implementation process and allow for a better interpretation of the results.
Trial RegistrationGerman Clinical Trials Register DRKS00022152; https://drks.de/search/de/trial/DRKS00022152
International Registered Report Identifier (IRRID)DERR1-10.2196/5168
Discrepancy between high clastogenic activity of trans-beta-nitrostyrene in vitro and lack in carcinogenicity might be related to inactivating metabolism and its high reactivity towards thiol groups
Diabetes Mellitus in Pregnancy Leads to Growth Restriction and Epigenetic Modification of the Srebf2 Gene in Rat Fetuses
Diabetic pregnancy is correlated with increased risk of metabolic and neurological disorders in the offspring putatively mediated epigenetically. Little is known about epigenetic changes already present in fetuses of diabetic pregnancies. We aimed at characterizing the perinatal environment after preexisting maternal diabetes mellitus and at identifying relevant epigenetic changes in the fetus. We focused on the transcription factor Srebf2 (sterol regulatory element binding transcription factor 2), a master gene in regulation of cholesterol metabolism. We tested whether diabetic pregnancy induces epigenetic changes in the Srebf2 promoter and if they become manifest in altered Srebf2 gene expression. We worked with a transgenic rat model of type 2 diabetes mellitus (Tet29) in which the insulin receptor is knocked down by doxycycline-induced RNA interference. Doxycycline was administered preconceptionally to Tet29 and wild-type control rats. Only Tet29 doxycycline dams were hyperglycemic, hyperinsulinemic, and hyperlipidemic. Gene expression was analyzed with quantitative real-time reverse transcriptase polymerase chain reaction and CpG promoter methylation with pyrosequencing. Immunohistochemistry was performed on fetal brains. Fetuses from diabetic Tet29 dams were hyperglycemic and growth restricted at the end of pregnancy. They further displayed decreased liver and brain weight with concomitant decreased microglial activation in the hippocampus in comparison to fetuses of normoglycemic mothers. Importantly, diabetic pregnancy induced CpG hypermethylation of the Srebf2 promoter in the fetal liver and brain, which was associated with decreased Srebf2 gene expression. In conclusion, diabetic and hyperlipidemic pregnancy induces neurological, metabolic, and epigenetic alterations in the rat fetus. Srebf2 is a potential candidate mediating intrauterine environment-driven epigenetic changes and later diabetic offspring health