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Visible/Multi-terahertz 2-Dimensional Spectroscopy of Ultrafast Carrier Dynamics in Quantum Materials
No full textUltrafast dynamics observed at low energies carry insightful information about the complex many-body interactions in solid-state materials. Here, we present a highly sensitive and robust setup for asymmetric 2-dimensional spectroscopy performing 2-pulse visible excitation combined with probing in the 15- to 35-THz frequency range. This experimental setup is ideal for targeting the interplay of high- and low-energy correlations in functional materials with femtosecond temporal and millielectronvolt energy resolution. In addition, the sub-cycle field resolution of mid-infrared pulses enables tracking nonthermal interactions in the complex dielectric function. Prototypical measurements benchmark ultrafast carrier dynamics in thin-film graphite, showing in detail the interplay of direct and indirect optical transitions in the transient excited state. We further investigate the photo-induced collapse of the superconducting condensate in the high-temperature superconductor Bi2Sr2CaCu2O8+x at energies resonant to the optical bandgap, revealing a nontrivial instantaneous nonlinearity related to the excited quasiparticles in the material. Optical pump–terahertz probe experiments build the foundation for this evolutionary step in 2-dimensional spectroscopy as well as for terahertz 4-wave mixing with resonant driving and readout of the superconducting state. Our results offer exciting perspectives in the study of strong correlations and enable precise investigations of nontrivial many-body interactions in few-layer samples and nanostructures.publishe
Beyond the National Open Science Sphere : Organising the ERUA Open Science Live Meet-Ups
No full textThe Open Science Community reaches beyond national borders, which entails the necessity of international exchange to learn from each other and to develop measures jointly. But how to implement formats of exchange? In this report, Maximilian Heber and Dr. Goran Sekulovski share their experiences planning and performing the ERUA Open Science Live Meet-Ups, a low-threshold format of exchange implemented whitin the European Reform Universities Alliance (ERUA), an alliance of the European Universities Initiative (EUI). Doing so, they reflect critically on this format, hoping that this paper may be a resource of inspiration for others who may be interested in setting up similar initiatives.publishe
Trait dissociation is associated with dissociative experiences arising from disrupted multisensory integration
No full textDissociation is a transdiagnostic mental health symptom involving a sense of detachment from one’s own body. A coherent percept of our body relies upon the smooth integration of different senses, such as vision and touch, which are processed by the brain at different speeds. We investigated the association between multi-sensory integration and dissociation in a N = 100 non-clinical sample. An immersive head-mounted display provided participants with a first-person view of their body while their arm was brushed by themselves or by the researcher. This mixed-reality setup allowed for the systematic variation of a delay to the visual feed, resulting in visual information being delayed relative to other senses (e.g. touch). Larger delays were associated with greater self-reported feelings of dis-ownership from the body. In addition, participants with high trait dissociation felt elevated sensations of dis-ownership from the body and were more sensitive to the multi-sensory delay, suggesting an increased tendency to ‘fraction’ senses in dissociation. Moreover, individuals with higher dissociation displayed similar cardiac reactivity to both self and other touch. These findings highlight two key mechanisms underlying dissociation; altered sensory-integration and increased awareness of self-action.publishe
Emergence of a novel drinking innovation in an urban population of sulphur-crested cockatoos, Cacatua galerita
No full textThe spread of innovation has been proposed as a potentially important source of adaptive behavioural responses to anthropogenic change. Yet, while a diversity of urban innovations have been documented in animals, there are relatively few examples of these spreading to form local traditions. One notable example is the ‘bin-opening innovation’ in sulphur-crested cockatoos (Cacatua galerita), where individuals open household bin lids to access food waste, with this behaviour spreading across southern Sydney, Australia. Here, we describe a second innovation in this species, the ‘drinking-fountain innovation’. Individuals from a population in western Sydney drink from twist-handle public drinking fountains, with this behaviour persisting over at least 2 years. Successful operation requires a coordinated sequence of actions, with only 41% of observed attempts ending in success. Intensive observation at one drinking fountain over 44 days revealed 525 attempts and 46% of marked individuals successfully engaging in the behaviour, with individuals visiting at dawn and dusk in line with expectations for use of a water resource. Public drinking fountains vary in design between local councils but are generally widespread. Yet, to our knowledge, this behaviour has not been observed elsewhere. Altogether, this suggests that this drinking innovation has spread to form a new urban-adapted local tradition.publishe
Did internet use protect older adults’ mental health during the COVID-19 pandemic? : It depends on their pre-pandemic social connectedness
No full textMany studies have addressed changes in mental health during the COVID-19 pandemic's early lockdown stage. Fewer studies have investigated the further developments in older adults' mental health throughout the pandemic's later stages. Research gaps particularly pertain to the role of how online information search behaviour and offline social network interact. Both provide important resources (e.g., information, support, services) that are essential for independence and well-being in later life. By investigating how they interact, we propose four theoretically derived mechanisms and test them using high-quality data.
Based on the Survey of Health, Ageing and Retirement in Europe's (SHARE) wave eight (2019) and second Corona survey (May–September 2021), we apply multinomial logistic regressions to predict stability and increase of depressive mood between the first and the second pandemic phases among 30,076 adults aged 50 years or older, observed in 27 countries. Results show that increased government information search online is associated with increased depressive mood. Pre-pandemic social connectedness moderates the associations between internet use and depressive mood positively, decreasing the risk of depressive mood among internet non-users and pointing to compensation of lacking online resources via offline social ties. Additionally, the negative effects of increased government information search were aggravated by deeper social connectedness, pointing to conflicts or disagreements over pandemic governance policy that may arise in close social networks.publishe
Scaling Distributed Collaboration in Mixed Reality
No full textDistributed collaboration in Mixed Reality (MR) promises to revolutionise how people connect across different physical environments, offering experiences akin to face-to-face interactions. However, previous work has mostly focused on enabling this vision in overly simplified settings such as with only two users interacting in identical distributed environments. Scaling current systems to work with large groups and for common real-life scenarios is a persistent challenge that requires addressing multiple tensions. We identified six challenges: 1) supporting locally congruent actions from heterogeneous remote spaces, 2) communicating accurate user behaviours through virtual representation instead of physical bodies, 3) facilitating organic group interactions within limited physical space, 4) maintaining conversational dynamics even in asynchronous exchanges, 5) providing equal access to physical objects for all participants, and 6) enabling efficient task switching within a complex ecology of applications, devices, and accessibility needs. This workshop aims to gather researchers and practitioners to explore actionable strategies for resolving these challenges. Through a mix of presentations, hands-on activities, and group discussions, participants will generate new ideas and develop a research agenda to articulate the future of MR collaboration systems. The workshop outcomes will include a list of concrete next steps for the community to bring distributed MR collaboration at scale.publishe
Deconstructing blocking statutes : why extraterritorial legislation cannot violate the sovereignty of other states
No full textBlocking statutes are national provisions that aim to combat the legal consequences of foreign, extraterritorial legislation. They are often justified by an alleged necessity to protect domestic sovereignty. This article challenges this assumption based on an in-depth discussion of the sovereignty principle and its interplay with the exercise of state power regarding foreign facts. In particular, it shows why a distinction between the law’s territorial scope of sovereign validity and its potentially extraterritorial scope of application is warranted and why, based on these foundations, extraterritorial legislation cannot violate foreign sovereignty. Since Blocking Statutes cannot be understood to protect domestic sovereignty, the article also discusses how they serve to enforce international principles on extraterritorial legislation instead.publishe
From idle to interaction : assessing social dynamics and unanticipated conversations between social robots and residents with mild cognitive impairment in a nursing home
No full textThis paper examines the potential impact of social robots on people with mild cognitive impairments in a nursing home. Within a 4-month design case study, we investigated the practices, attitudes, and social contexts of residents with mild cognitive impairment and their caregivers and designed two prototype apps for a robotic-based system. Subsequently, 10 residents, the former nursing home manager, and one social caregiver participated in a prototype evaluation study for 10 weeks. The goal was to assess group-based user experience and social interactions. Qualitative results indicate that the system can support participants in their individual, social, and daily activities and, therefore, consequently initiate potentially meaningful interactions. One key observation from the video analysis was that the participants initiated unanticipated conversations with the robot, which we discuss regarding the prompting character, design appearance, and affordances of the robot in interaction.publishe
The German national cohort study on the development of motor performance, physical activity and health in children and adolescents: the MoMo 2.0-Study protocol
No full textIntroduction: Regular physical activity (PA) and good motor performance are essential for children’s physical and mental health. However, historical trends suggest that levels of PA and motor performance in children and adolescents are at a low point. The relationships between PA, motor performance, health and their respective determinants, as well as their individual development throughout childhood and adolescence, are not yet fully understood. Therefore, continuous monitoring of PA, motor performance and health is needed to identify vulnerable subpopulations and provide data for policy-makers and health promotion professionals. The Motorik Monitoring 2.0-Study aims to analyse the developmental, historical and periodic trends in motor performance and PA, as well as the underlying determinants, in children and adolescents in Germany.
Methods and analysis: A representative sample of children and adolescents aged 4–17 years is drawn across 195 sample points in Germany. The assessment, carried out by test instructors, includes (1) a PA questionnaire covering different settings, including determinants, (2) anthropometric measures, (3) fine and gross motor performance tests focusing on coordination, flexibility, strength and endurance, (4) 24 hours device-based measured physical behaviour by accelerometry for 1 week and (5) a health interview focusing on health behaviour, physical and mental health as well as socioeconomic status. In addition, external data may be linked to the study using geographical information systems (eg, area deprivation, access to sports facilities). Analyses will be conducted using mixed-effects models to account for the nationwide structure of the study.
Ethics and dissemination: Ethical approval was obtained from the Ethics Committee of the Karlsruhe Institute of Technology. Results will be published in open-access scientific journals and disseminated at congresses for scientists, policy-makers and stakeholders.publishe