The importance of hole concentration in establishing carrier-mediated ferromagnetism in Mn doped Ge

In the present work, we have prepared Mn-doped Ge using different annealing approaches after Mn ion implantation, and obtained samples with hole concentrations ranging from 10^18 to 2.1x10^20 cm^-3, the latter being the highest reported so far. Based on the magnetotransport properties of Mn doped Ge, we argue that the hole concentration is a decisive parameter in establishing carrier-mediated ferromagnetism in magnetic Ge.Comment: 7 pages, 3 figure

Cognitive architecture of perceptual organization: from neurons to gnosons

What, if anything, is cognitive architecture and how is it implemented in neural architecture? Focusing on perceptual organization, this question is addressed by way of a pluralist approach which, supported by metatheoretical considerations, combines complementary insights from representational, connectionist, and dynamic systems approaches to cognition. This pluralist approach starts from a representationally inspired model which implements the intertwined but functionally distinguishable subprocesses of feedforward feature encoding, horizontal feature binding, and recurrent feature selection. As sustained by a review of neuroscientific evidence, these are the subprocesses that are believed to take place in the visual hierarchy in the brain. Furthermore, the model employs a special form of processing, called transparallel processing, whose neural signature is proposed to be gamma-band synchronization in transient horizontal neural assemblies. In neuroscience, such assemblies are believed to mediate binding of similar features. Their formal counterparts in the model are special input-dependent distributed representations, called hyperstrings, which allow many similar features to be processed in a transparallel fashion, that is, simultaneously as if only one feature were concerned. This form of processing does justice to both the high combinatorial capacity and the high speed of the perceptual organization process. A naturally following proposal is that those temporarily synchronized neural assemblies are “gnosons”, that is, constituents of flexible self-organizing cognitive architecture in between the relatively rigid level of neurons and the still elusive level of consciousness

Consequences of late breeding on moult and recovery rate of a long-distance migrant, the Wheatear (Oenanthe oenanthe)

Unsere Studie hat am Steinschmätzer die Folgen einer verlängerten Brutzeit durch zusätzliche Spätbruten für das Zeitmanagement von Weitstreckenziehern untersucht. Wir fragten, ob der Zeitverlauf der Mauser verändert wird, ob saisonale Aktivitäten verschachtelt werden und ob die Geschlechter unterschiedlich auf spätes Brüten reagieren. Zudem erwarteten wir eine verminderte Rückkehrrate von Spätbrütern. Die Ergebnisse zeigen, dass Steinschmätzer beider Geschlechter ohne Spätbruten kurz nach dem Ausfliegen der Jungen gleichzeitig mit der Mauser beginnen, während spät brütende Steinschmätzer den Mauserbeginn verzögern. Die Verzögerung ist bei den Weibchen (23 Tage) viel ausgeprägter als bei den Männchen (6 Tage). Infolgedessen überlappten spätbrütende Männchen häufig Brut und Mauser, während die Weibchen möglicherweise vor dem Zugbeginn in Zeitdruck gerieten. Trotz des späten Mauserbeginns wechselten Spätbrüter beider Geschlechter ihr Gefieder tendenziell um etwa eine Woche langsamer und konnten somit ihre Verspätung nicht kompensieren. Obwohl zwei Bruten für den Steinschmätzer sicher eine höhere Belastung darstellen, zeigten die Rückkehrraten keine Benachteiligung auf. Unabhängig von Alter, Geschlecht und Anzahl der Bruten lag die Rate im Populationsmittel bei 23,5 %. Vermutlich ziehen nur Steinschmätzer in ausgezeichneter körperlicher Verfassung Spätbruten auf und gleichen die zusätzliche Belastung aus.The present study investigates consequences of late breeding for the seasonal time management of long-distance migrants, as exemplified by the Wheatear. We examined whether the time course of moult was changed, whether seasonal activities were overlapped, and whether the sexes differed in the ways they modified seasonal behaviour when breeding late. Furthermore, we expected that late breeders would incur a cost of additional late breeding by reduced return rates. The results of the study showed that in Wheatears without late clutches both sexes initiated moult simultaneously soon after fledging of the clutch. Late breeders, in contrast, delayed moult onset. The delay was much more pronounced in females (23 days) than males (6 days). As a consequence, late breeding males but not females frequently overlapped breeding and moult, while females may have incurred time pressure to finish moult in time for migration. Despite the late onset of moult, its duration was extended by approximately one week, and therefore, late breeders did not compensate for their seasonal delay. Yet although double clutches are most likely to be demanding, late-breeding Wheatears showed no signs of decreased, but instead, tentatively elevated return rates. Return rates were independent of age, sex, and number of clutches and averaged 23.5 %. We propose that only Wheatears in excellent physical condition initiate additional late clutches and are able to compensate for any arising costs

Annual Report 2015 - Institute of Ion Beam Physics and Materials Research

After the successful evaluation in 2015 we started research and further development of our largescale facilities, in particular the Ion Beam Center (IBC), in the framework of Helmholtz’s Programmeoriented Funding scheme (POF) which coordinates scientific cooperation on a national and international scale. Most of our activities are assigned to the Helmholtz program “From Matter to Materials and Life” within the research area “Matter”, in cooperation with several other German Helmholtz Centers. Our in-house research is performed in three so-called research themes, as depicted in the schematic below. What is missing there for simplicity is a minor part of our activities in the program “Nuclear Waste Management and Safety” within the research area “Energy”. A few highlights which have been published in 2015 are reprinted in this annual report in order to show the variety of the research being performed at the Institute, ranging from self-organized pattern formation during ion erosion or DNA origami patterning, over ferromagnetism in SiC and TiO2 to plasmonics and THz-spectroscopy of III-V semiconductors. A technological highlight published recently is the demonstration of nanometer scale elemental analysis in a Helium ion microscope, making use of a time-of-flight detector that has been developed at the IBC. In addition to these inhouse research highlights, also users of the IBC, in particular of the accelerator mass spectrometry (AMS), succeeded in publishing their research on geomorphology in Nepal in the high-impact journal Science (W. Schwanghart et al., Science 351, 147 (2015)), which demonstrates impressively the added value of transdisciplinary research at the IBC. In order to further develop the IBC, we have started in 2015 the design and construction of our new low energy ion nanoengineering platform which was highly recommended by the POF evaluators. It will consist of two-dimensional materials synthesis and modification, high-resolution ion beam analysis and high-resolution electron beam analysis and will come into full operation in 2019

Annual Report 2021 - Institute of Ion Beam Physics and Materials Research

The year 2021 was still overshadowed by waves of the COVID-19 pandemic, although the arrival of efficient vaccinations together with the experience of the preceding year gave us a certain routine in handling the situation. By now the execution of meetings in an online mode using zoom and similar video conference systems has been recognized as actually being useful in certain situations, e.g. instead of flying across Europe to attend a three-hours meeting, but also to be able to attend seminars of distinguished scientists which otherwise would not be easily accessible. The scientific productivity of the institute has remained on a very high level, counting 190 publications with an unprecedented average impact factor of 8.0. Six outstanding and representative publications are reprinted in this Annual Report. 16 new third-party projects were granted, among them 7 DFG projects, but very remarkably also an EU funded project on nonlinear magnons for reservoir computing with industrial participation of Infineon Technologies Dresden and GlobalFoundries Dresden coordinated by Kathrin Schultheiß of our Institute. The scientific success was also reflected in two HZDR prizes awarded to the members of the Institute: Dr. Katrin Schultheiß received the HZDR Forschungspreis for her work on “Nonlinear magnonics as basis for a spin based neuromorphic computing architecture”, and Dr. Toni Hache was awarded the Doktorandenpreis for his thesis entitled “Frequency control of auto-oscillations of the magnetization in spin Hall nano-oscillators”. Our highly successful theoretician Dr. Arkady Krasheninnikov was quoted as Highly Cited Researcher 2021 by Clarivate. The new 1-MV facility for accelerator mass spectrometry (AMS) has been ordered from NEC (National Electrostatics Corporation). Design of a dedicated building to house the accelerator, the SIMS and including additional chemistry laboratories for enhanced sample preparation capabilities has started and construction is planned to be finished by mid 2023, when the majority of the AMS components are scheduled for delivery. In the course of developing a strategy for the HZDR - HZDR 2030+ Moving Research to the NEXT Level for the NEXT Gens - six research focus areas for our institute were identified. Concerning personalia, it should be mentioned that the long-time head of the spectroscopy department PD Dr. Harald Schneider went into retirement. His successor is Dr. Stephan Winnerl, who has been a key scientist in this department already for two decades. In addition, PD Dr. Sebastian Fähler was hired in the magnetism department who transferred several third-party projects with the associated PhD students to the Institute and strengthens our ties to the High Magnetic Field Laboratory, but also to the Institute of Fluid Dynamics. Finally, we would like to cordially thank all partners, friends, and organizations who supported our progress in 2021. First and foremost we thank the Executive Board of the Helmholtz-Zentrum Dresden-Rossendorf, the Minister of Science and Arts of the Free State of Saxony, and the Ministers of Education and Research, and of Economic Affairs and Climate Action of the Federal Government of Germany. Many partners from universities, industry and research institutes all around the world contributed essentially, and play a crucial role for the further development of the institute. Last but not least, the directors would like to thank all members of our institute for their efforts in these very special times and excellent contributions in 2021

Women want the heavens, men want the earth

This version of the article may not completely replicate the final version published in Journal of Individual Differences.. It is not the version of record and is therefore not suitable for citation. The version of record can be found at https://doi.org/10.1027/1614-0001/a00028