Georg-August-Universität Göttingen
  • Göttingen, Niedersachsen, Germany
Recent publications
Conversational Agents (CAs) are becoming part of our everyday lives. About 10% of users display aggressive behavior toward CAs, such as swearing at them when they produce errors. We conducted two online experiments to understand user aggression towards CAs better. In the first experiment, 175 participants used either a humanlike CA or a non-humanlike CA. Both CAs worked without errors, and we observed no increased frustration or user aggression. The second experiment (with 201 participants) was the focus of this study; in it, both CAs produce a series of errors. The results show that frustration with errors drives aggression, and users with higher impulsivity are more likely to become aggressive when frustrated. The results also suggest that there are three pathways by which perceived humanness influences users’ aggression towards CAs. First, perceived humanness directly increases the frustration with the CA when it produces errors. Second, perceived humanness increases service satisfaction, which in turn reduces frustration. Third, perceived humanness influences the nature of aggression when users become frustrated (i.e., users are less likely to use highly offensive words with a more humanlike CA). Our research contributes to our theoretical understanding of the role of anthropomorphism in the interaction with machines, showing that designing a CA to be more humanlike is a double-edged sword—both increasing and decreasing the frustration that leads to aggression—and also a means to reduce the most severe aggression.
The viable but non-culturable (VBNC) state is a persistence strategy adopted by bacteria to withstand long-lasting periods of unfavorable conditions. VBNC cells evade classical detection methods and are therefore easily transmitted in the hospital causing relapsing infections. The opportunistic human pathogen Acinetobacter baumannii has become a major threat in health care institutions and the food industry due to multiple antibiotic resistances and its ability to quickly adapt to very different ecological niches. Here, we report an additional, novel survival strategy of A. baumannii . Upon prolonged incubation in high-salt media, cells became unculturable. However, LIVE/DEAD staining followed by flow cytometry, respiratory activity assays, and resuscitation experiments revealed that these cells were viable but non-culturable. VBNC cells underwent large morphological changes. Entry into the VBNC state was also induced by pH and temperature stress, as well as by desiccation and anaerobiosis. The VBNC state was found in several strains of A. baumannii . Genome-wide expression profiling revealed a plethora of genes differentially regulated upon entry into the VBNC state. In summary, this study presents unequivocal evidence for a dormancy state in A. baumannii that has important consequences for detection of this pathogen and recurrent outbreaks. IMPORTANCE Currently, the viable but non-culturable (VBNC) state is an underappreciated niche for pathogenic bacteria which provides a continuous source for recurrent infections and transmission. We propose the VBNC state to be a global persistence mechanism used by various A. baumannii strains to cope with many stresses it is confronted with in the clinical environment and in the host. This requires a novel strategy to detect viable cells of this pathogen that is not only based on plating assays.
Cutaneous squamous cell carcinomas are the second most frequent skin tumor after basal cell carcinoma and make up 20% of all non-melanocytic skin tumors. This article presents the case of a 41-year-old male patient who presented for treatment of a dermatohistologically confirmed carcinoma with squamous cell differentiation of the occipital scalp. The process began ca. 9 years ago with a nonhealing pustule and the growth continued to advance. At the time of presentation the alteration had reached a size that was no longer tolerable in daily life. A surgical histographically controlled R0 resection according to the guidelines and coverage of the defect using a free latissimus muscle transplant were carried out due to the immense size of the tumor of ca. 20 × 30 cm. The patient is currently in closely controlled follow-up care. He has been successfully rehabilitated and his daily routine consists of relatively unlimited work and leisure activities. This case impressively illustrates the importance of the early recognition and rapid surgical intervention in carcinomas of the skin. The size of the tumor and simultaneously deteriorating prognosis were based on the growth period of ca. 9 years and primarily by the extremely reluctant behavior of the patient.
Bentheim Sandstone is considered a suitable conventional georeservoir rock even at great depth because of its mineral composition, homogeneity, micro- and macrostructure, and is also used as a reference material in rock deformation tests. However, a full characterization of the permeability at representative depths has never been performed. Here we report new experimental data where the permeability of Bentheim Sandstone is measured both with a simultaneous variation and with a sequential variation of three different variables to simulate georeservoir conditions. The results indicate a decrease in permeability with simulated increasing depth until 2–3 km, followed by a partial permeability recovery until 4–5 km depth. During the exhumation path, initially, permeability is unaffected, but at shallow depths, a sharp increase in permeability is observed, likely due to microcracking. These variations are a consequence of a complex interaction between stress, pore pressure and temperature, highlighting the importance of experiments considering all three variables when studying the evolution of permeability at depth. These results will aid with the accurate estimation of permeability at different georeservoir conditions.
The chemistry of alkali‐metal enolates is dominated by ion pairing. To improve our understanding of the intrinsic interactions between the alkali‐metal cations and the enolate anions, we have applied Cooks’ kinetic method to determine relative M+ (M = Li, Na, K) affinities of the stabilized enolates derived from acetylacetone, ethyl acetoacetate, diethyl malonate, ethyl cyanoacetate, 2‑cyanoacetamide, and methyl malonate monoamide in the gas phase. Quantum chemical calculations support the experimental results and moreover afford insight into the structures of the alkali‐metal enolate complexes. The affinities decrease with increasing size of the alkali‐metal cations, reflecting weaker electrostatic interactions and lower charge densities of the free M+ ions. For the different enolates, a comparison of their coordinating abilities is complicated by the fact that some of the free anions undergo conformational changes resulting in stabilizing intramolecular interactions. If these complicating effects are disregarded, the M+ affinities correlate with the electron density of the chelating functionalities, i.e., the carbonyl and/or the nitrile groups of the enolates. A comparison with the known association constants of the corresponding alkali‐metal enolates in solution points to the importance of solvation effects for these systems.
Respect for the patient’s right to self-determination and the professional medical assessment of the (continued) existence of a therapeutic prospect of success of the respective curative intervention (“indication”) are the two central reference parameters of every medical therapeutic decision. This is particularly true in cases of a progressive, irreversible, fatal course of the disease. However, the assessment of the presumed will of the patient or the meaningfulness of curative (intensive care) prolongation of life frequently causes difficulties. The law cannot eliminate these doubts in each individual case; it does, however, provide a framework so that factually and ethically justified therapy decisions can be made in each case. In this function, this legal framework—no matter how much it must first be concretized in the respective decision case—demands strict observance. This also includes the most recent change in the law that went into effect on 1 January 2023, through the introduction of a statutory right of (emergency) representation for spouses.
Introduction/Background Multiple deep-learning techniques in colposcopy have been tested over the past years with diagnostic accuracy results varying between 50 and 97%. The goal of this study was to evaluate the accuracy of a novel perceiver classification method after an automated segmentation method of digital images of the uterine cervix. Methodology 1,423 digital native, aceto and iodine colposcopy images with colposcopy assessment (Rio 2001 classification) and cervical biopsy result from 484 patients with cervical intraepithelial neoplasm results of the Freiburg colposcopy clinic were collected and analyzed (time period 2017 – 2021). The images were down-sampled and the segmentation was performed by identifying a small core of the region of interest (ROI) followed by expanding this small core to the actual one by using a label propagation algorithm on the neighborhood graph of the super pixels. To classify the images to the CIN categories, perceiver which is a transformer based deep neural network has beed trained and tested. An implementation of the of the applied network is available in Keras Github. Results Normal/uncertain/minor changes/major changes colposcopy findings were observed in 175 (25%), 15 (2%), 250 (36%) and 260 (37%) patients with corresponding diagnoses of CIN I/CIN II/CIN III/invasive cancer in 27 (4%), 71 (10%), 154 (22%), 47 (6%) patients. Automated segmentation identified the ROI in 98.7%. The perceiver classification achieved 100% test accuracies on a nested cross fold validation setting. Conclusion This novel automated image segmentation and classification of digital colposcopy images outperforms most current state of the art methods. A prospective assessment will assess its external validity and clinical usefulness. Disclosures no disclosures
A bstract The possibility to reanalyse data taken by the HERA experiments offers the chance to study modern QCD jet and event-shape observables in deep-inelastic scattering. To address this, we compute resummed and matched predictions for the 1-jettiness distribution in neutral current DIS with and without grooming the hadronic final state using the soft-drop technique. Our theoretical predictions also account for non-perturbative corrections from hadronisation through parton-to-hadron level transfer matrices extracted from dedicated Monte Carlo simulations with S herpa . To estimate parameter uncertainties in particular for the beam-fragmentation modelling we derive a family of replica tunes to data from the HERA experiments. While NNLO QCD normalisation corrections to the NLO+NLL’ prediction are numerically small, hadronisation corrections turn out to be quite sizeable. However, soft-drop grooming significantly reduces the impact of non-perturbative contributions. We supplement our study with hadron-level predictions from S herpa based on the matching of NLO QCD matrix elements with the parton shower. Good agreement between the predictions from the two calculational methods is observed.
Women’s capacity to reproduce varies over the life span, and developmental goals such as family formation are age-graded and shaped by social norms about the appropriate age for completing specific developmental tasks. Thus, a woman’s age may be linked to her ideas about what an ideal partner should be like. With the goals of replicating and extending prior research, in this study we examined the role of age in women’s partner preferences across the globe. We investigated associations of age with ideal long-term partner preferences in a cross-cultural sample of 17,254 single (i.e., unpartnered) heterosexual women, ages 18 to 67, from 147 countries. Data were collected via an online questionnaire, the Ideal Partner Survey. Confirming our preregistered hypotheses, we found no or only negligible age effects on preferences for kindness-supportiveness, attractiveness, financial security-successfulness, or education-intelligence. Age was, however, positively associated with preferences for confidence-assertiveness. Consistent with family formation goals, age was associated with an ideal partner’s parenting intentions (high until approximately age 30, then decreasing afterward). Age range deemed acceptable (and in particular, the discrepancy between one’s own age and the minimum ideal age of a partner) increased with age. This latter pattern also replicated in exploratory analyses based on subsamples of lesbian and bisexual women. In summary, age has a limited impact on partner preferences. Of the attributes investigated, only preference for confidence-assertiveness was linked with age. However, age range deemed acceptable and an ideal partner’s parenting intention, a dimension mostly neglected in earlier research, substantially vary with age.
Acute ischemic stroke induces rapid neuronal death and time is a key factor in its treatment. Despite timely recanalization, malignant cerebral infarction can ensue, requiring decompressive surgery (DC). The ideal timing of surgery is still a matter of debate; in this study, we attempt to establish the ideal time to perform surgery in this population. We conducted a retrospective study of patients undergoing DC for stroke at our department. The indication for DC was based on drop in level of consciousness and standard imaging parameters. Patients were stratified according to the timing of DC in four groups: (a) “ultra-early” ≤12 h, (b) “early” >12≤24 h, (c) “timely” >24≤48 h, and (d) “late” >48 h. The primary endpoint of this study was in-house mortality, as a dependent variable from surgical timing. Secondary endpoint was modified Rankin scale at discharge. In a cohort of 110 patients, the timing of surgery did not influence mortality or functional outcome (p=0.060). Patients undergoing late DC were however significantly older (p=0.008), and those undergoing ultra-early DC showed a trend towards a lower GCS at admission. Our results add to the evidence supporting an extension of the time window for DC in stroke beyond 48 h. Further criteria beyond clinical and imaging signs of herniation should be considered when selecting patients for DC after stroke to identify patients who would benefit from the procedure.
Heterogeneous structures are ubiquitous in natural organisms. Native heterogeneous structures inspire many artificial structures that are playing important roles in modern society, while it is challenging to identify the relevant factors in forming these structures due to the complexity of living systems. Here, hybrid hydrogels consisting of flexible polymer networks with embedded stiff cellulose nanocrystals (CNCs) are considered an open system to simulate the generalized formation of heterogeneous core-sheath structures. As the result of the modified air drying process of hybrid hydrogels, the formation of heterogeneous core-sheath structure is found to be correlated to the relative evaporation speed. Specifically, the formation of such heterogeneity in xerogel fibers is found to be correlated with the divergence of Deborah number (De). During the transition of De from large to small values with accompanying morphologies, the turning point is around De = 1. The mechanism can be considered a relative humidity-dependent glass transition behavior. These unique heterogeneous structures play a key role in tuning water permeation and water sorption capacity. Insights into these aspects can prospectively contribute to a better understanding of the native heterogeneous structures for bionics design.
The Global Ecosystem Dynamics Investigation (GEDI) aims to provide improved characterization of forest structure, and plant area index (PAI) is one of many variables provided in the official GEDI Level 2B (L2B) product suite. However, since release, few quantitative validation studies have been conducted. To reach Stage 1 of the validation hierarchy proposed by the Land Product Validation (LPV) sub-group of the Committee on Earth Observation Satellites (CEOS) Working Group on Calibration and Validation (WGCV), we provide an initial assessment of PAI estimates from GEDI’s L2B product. This is achieved using 18 in situ reference measurements available through the Copernicus Ground Based Observations for Validation (GBOV) service. We show that GEDI L2B PAI retrievals provide a nearly unbiased estimate of effective (PAI <sub xmlns:mml="" xmlns:xlink="">e</sub> ) (RMSD = 0.95, bias = 0.02, slope = 1.07), but systematically underestimate PAI (RMSD = 1.42, bias = -0.91, slope = 0.77). This is attributed to an assumed random distribution of plant material in the algorithm. To reach Stage 2 of the CEOS WGCV LPV hierarchy, continued work is needed to validate the product against additional in situ reference measurements covering further locations and time periods.
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12,262 members
Bela Gipp
  • Faculty of Mathematics and Computer Science
Birgit Schmidt
  • University Libraries
Fabian Brambach
  • Biodiversity, Macroecology, Biogeography
Colen Liesbeth
  • Department of Agricultural Economics and Rural Development
Wilhelmsplatz 1, 37073, Göttingen, Niedersachsen, Germany
Head of institution
Dr. Valérie Schüller
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