Influences on the formability and mechanical properties of 7000-aluminum alloys in hot and warm forming

Aluminum alloys of the 7000 series possess high lightweight potential due to their high specific tensile strength combined with a good ultimate elongation. For this reason, hot-formed boron-manganese-steel parts can be substituted by these alloys. Therefore, the application of these aluminum alloys for structural car body components is desired to decrease the weight of the body in white and consequently CO2 emissions during vehicle operation. These days, the limited formability at room temperature limits an application in the automobile industry. By increasing the deformation temperature, formability can be improved. In this study, two different approaches to increase the formability of these alloys by means of higher temperatures were investigated. The first approach is a warm forming route to form sheets in T6 temper state with high tensile strength at temperatures between 150 °C and 300 °C. The second approach is a hot forming route. Here, the material is annealed at solution heat treatment temperature and formed directly after the annealing step. Additionally, a quench step is included in the forming stage. After the forming and quenching step, the sheets have to be artificially aged to achieve the high specific tensile strength. In this study, several parameters in the presented process routes, which influence the formability and the mechanical properties, have been investigated for the aluminum alloys EN AW7022 and EN AW7075. © Published under licence by IOP Publishing Ltd

Three-Dimensional Observation of Atmospheric Processes in Cities

To cope with weather and climate-induced impacts as well as with air pollution in cities, the German research programme “Urban Climate Under Change” ([UC]2) aims at developing, testing and validating a new urban climate model, which is able to cover the full range of temporal and spatial scales of urban atmospheric processes. The project “Three-dimensional Observation of Atmospheric Processes in Cities” (3DO), which forms the module B of the [UC]2 research programme, aims at acquisition of comprehensive, accurate three-dimensional observational data sets on weather, climate and air quality in the German cities of Berlin, Hamburg and Stuttgart. Data sets from long-term observations and intense observation periods allow for evaluation of the performance of a new urban climate model called PALM‑4U that is developed by the project “Model-based city planning and application in climate change” (MOSAIK), which forms the module A of the [UC]2 research programme. This article focuses on collaborative activities for compilation of existing and acquisition of new observational data within the 3DO project

Correction: Mechanical properties of femoral trabecular bone in dogs

<p>Abstract</p> <p>After the publication of this work <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>, we became aware of the fact that the frequency of the ultrasound transmitter that we used for determining the elastic moduli of the trabecular bone specimens was not correctly specified. The oscillation frequency of the ultrasound transmitter was 2 MHz (and not 100 MHz as stated in our work) while we used a sampling rate of 100 MHz. In our publication, the oscillation frequency and sampling rate were confounded. Therefore also the statement in the discussion that we might have determined elastic moduli of trabecular bone tissue rather than the elastic properties of whole specimens because we used an ultrasound frequency > 2 MHz is wrong and has to be omitted.</p> <p>For measurement, the cubic bone specimens were not immersed in Ringer's solution but only were kept moist all the time.</p> <p>Apart from these corrections concerning the methods and interpretation of the data, the results reported in our publication and the conclusions are absolutely correct.</p> <p>We apologize for the inconvenience that this inaccuracy may have caused.</p

FAO – State of the world’s forests: forest fragmentation

This document summarizes the design process, definitions, and algorithmic implementation conducted by the Joint Research Centre to support the development and implementation of FAO’s global forest analysis for the thematic topics Accounting and Fragmentation. The analysis scheme and data products were designed to support the indicator Forest Fragmentation in the State of the World's Forests (SOFO) report 2020. The spatial forest coverage is assessed from the Copernicus Global Land Cover 2015 dataset (accessed in July 2019) and 21 Global Ecological Zones (GEZ). All data was re-projected to equal area to allow for comparable area estimates across the Globe. Spatially explicit maps and statistical summaries are derived at global level and for each of the 21 GEZ.JRC.D.1-Bio-econom

Cholinergic modulation of epileptiform activity in the developing rat neocortex

The effects of carbachol on picrotoxin-induced epileptiform activity and membrane properties of neurons in the developing rat neocortex were examined in an in vitro slice preparation. Intracellular recordings were obtained in layer II–III neurons of slices prepared from rats 9–21 days of age. Epileptiform activity in 9- to 14-day-olds consisted of a sharply rising, sustained (10–30 s) membrane depolarization with superimposed action potentials. Bath application of carbachol (5–50 μM) raised the threshold for evoking epileptiform activity but, when such responses were evoked, their underlying depolarizations were increased in amplitude. Orthodromic stimulation in slices from 15- to 21-day-old animals evoked a prolonged epileptiform burst response that triggered an episode of spreading depression (SD). Carbachol reduced epileptiform responses and suppressed the occurrence of SD. It did not significantly affect the resting membrane potential or the height of the action potential but decreased the rheobase current needed to evoke an action potential and increased the input resistance. All effects of carbachol were antagonized by atropine (1 μM). These results indicate that carbachol has both pre- and postsynaptic effects in the developing neocortex and can significantly modulate neuronal excitability in the immature nervous system

Leistungsprüfung offen-abblühender Maispopulationen

Auf modernem Zuchtmaterial basierende, offen-abblühende Maispopulationen könnten vor allem für ökologische und Low-Input Anbausysteme eine alternative zu Hybriden darstellen. Im Rahmen des zeitlich befristeten Experiments 2014/150/EU der EU-Kommission wurden 2016 fünf moderne Maispopulationen vom Bundessortenamt zugelassen. In einem BÖLN-Projekt wurden in 2017 und 2018 Leistungsprüfungen aller zugelassenen Maispopulationen (mit Hybriden als Referenzsorten) unter konventionellen und  ökologischen Anbaubedingungen durchgeführt. Wir stellen die Ergebnisse dieser Leistungsprüfungen vor, ziehen Schlussfolgerungen über das agronomische Potential von Maispopulationen und diskutieren zukünftige Perspektiven