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Motive Perception at First Impressions: On the Relevance of Targets’ Explicit and Implicit Motive Dispositions
No full textWhen people judge the motive dispositions of unacquainted others, are their judgments accurate
representations of the targets’ explicit motives, their implicit motives, or both? To address this
question, we assessed target persons’ explicit motives via self-report and their implicit motives via
a Picture Story Exercise as well as two recently developed affective contingency-based measures.
Targets were then filmed during a short, casual conversation. The recordings were shown to thirty
unacquainted observers who judged targets’ affiliation, power and achievement motives. For all
three motives, observer ratings were linked to explicit motives. For the affiliation and achievement
domains, ratings were also linked to implicit motives. We further investigated whether the extent
of congruence between observer ratings and motive ratings would depend on information
modality, this was not the case. The findings thus indicate that both explicit and implicit motives
are relevant for observer judgments, but that these effects are not modality-specific
Emotion Recognition beyond Pixels: Leveraging Facial Point Landmark Meshes
No full textDigital health apps have become a staple in daily life, promoting awareness and providing motivation for a healthier lifestyle. With an already overwhelmed healthcare system, digital therapies offer relief to both patient and physician alike. One such planned digital therapy application is the incorporation of an emotion recognition model as a tool for therapeutic interventions for people with autism spectrum disorder (ASD). Diagnoses of ASD have increased relatively rapidly in recent years. To ensure effective recognition of expressions, a system is designed to analyze and classify different emotions from facial landmarks. Facial landmarks combined with a corresponding mesh have the potential of bypassing hurdles of model robustness commonly affecting emotion recognition from images. Landmarks are extracted from facial images using the Mediapipe framework, after which a custom mesh is constructed from the detected landmarks and used as input to a graph convolution network (GCN) model for emotion classification. The GCN makes use of the relations formed from the mesh along with the special distance features extracted. A weighted loss approach is also utilized to reduce the effects of an imbalanced dataset. The model was trained and evaluated with the Aff-Wild2 database. The results yielded a 58.76% mean accuracy on the selected validation set. The proposed approach shows the potential and limitations of using GCNs for emotion recognition in real-world scenarios
Theta power relates to infant object encoding in naturalistic mother-infant interactions
No full textThis study investigates infants' neural and behavioral responses to maternal ostensive signals during naturalistic mother-infant interactions and their effects on object encoding. Mothers familiarized their 9- to 10-month-olds (N = 35, 17 females, mainly White, data collection: 2018–2019) with objects with or without mutual gaze, infant-directed speech, and calling the infant's name. Ostensive signals focused infants' attention on objects and their mothers. Infant theta activity synchronized and alpha activity desynchronized during interactions compared to a nonsocial resting phase (Cohen' d: 0.49–0.75). Yet, their amplitudes were unrelated to maternal ostensive signals. Ostensive signals did not facilitate object encoding. However, higher infant theta power during encoding predicted better subsequent object recognition. Results strengthen the role of theta-band power for early learning processes
Patient-Relevant Costs for Organ Preservation versus Radical Resection in Locally Advanced Rectal Cancer
No full textTotal neoadjuvant therapy (TNT) is an evolving treatment schedule for locally advanced
rectal cancer (LARC), allowing for organ preservation in a relevant number of patients in the case
of complete response. Patients who undergo this so-called “watch and wait” approach are likely
to benefit regarding their quality of life (QoL), especially if definitive ostomy could be avoided. In
this work, we performed the first cost-effectiveness analysis from the patient perspective to compare
costs for TNT with radical resection after neoadjuvant chemoradiation (CRT) in the German health care system. Individual costs for patients insured with a statutory health insurance were calculated
with a Markov microsimulation. A subgroup analysis from the prospective “FinTox” trial was
used to calibrate the model’s parameters. We found that TNT was less expensive (−1540 EUR)
and simultaneously resulted in a better QoL (+0.64 QALYs) during treatment and 5-year follow-up.
The average cost for patients under TNT was 4711 EUR per year, which was equivalent to 3.2% of
the net household income. CRT followed by resection resulted in higher overall costs for ostomy
care, medication and greater loss of earnings. Overall, TNT appeared to be more efficacious and
cost-effective from a patient’s point of view in the German health care system
Plant diversity and community age stabilize ecosystem multifunctionality
No full textIt is well known that biodiversity positively affects ecosystem functioning, leading to
enhanced ecosystem stability. However, this knowledge is mainly based on analyses
using single ecosystem functions, while studies focusing on the stability of ecosystem
multifunctionality (EMF) are rare. Taking advantage of a long-term grassland biodi-
versity experiment, we studied the effect of plant diversity (1–60 species) on EMF
over 5 years, its temporal stability, as well as multifunctional resistance and resilience
to a 2-year drought event. Using split-plot treatments, we further tested whether a
shared history of plants and soil influences the studied relationships. We calculated
EMF based on functions related to plants and higher-trophic levels. Plant diversity
enhanced EMF in all studied years, and this effect strengthened over the study pe-
riod. Moreover, plant diversity increased the temporal stability of EMF and fostered
resistance to reoccurring drought events. Old plant communities with shared plant
and soil history showed a stronger plant diversity–multifunctionality relationship and
higher temporal stability of EMF than younger communities without shared histories.
Our results highlight the importance of old and biodiverse plant communities for EMF
and its stability to extreme climate events in a world increasingly threatened by global
change
Tree diversity and mycorrhizal type co-determine multitrophic ecosystem functions
No full text1. The relationship between biodiversity and multitrophic ecosystem functions
(BEF) remains poorly studied in forests. There have been inconsistent reports
regarding the significance of tree diversity effects on ecosystem functions, which
may be better understood by considering critical biotic interactions of trees.
2. This study investigates the role of tree-mycorrhizal associations that may shape
forest BEF relationships across multiple ecosystem functions. We used a field
experiment (MyDiv) that comprises 10 deciduous tree species associated with
either arbuscular mycorrhizal (AM) or ectomycorrhizal (EcM) fungi to create gradients in species richness (1, 2, 4 species) and different mycorrhizal communities
(only AM-species [AM fungi associated tree species] or EcM-species [EcM fungi
associated tree species], or a combination of both). We investigated the effects
of tree species richness and mycorrhizal types on crucial multitrophic ecosystem
functions (foliage damage, predation [using artificial caterpillars] and soil fauna
feeding activity [~0–10 cm]) and assessed how these effects were mediated by
stand characteristics.
3. Overall, we found that tree species richness and mycorrhizal types strongly affected multitrophic ecosystem functions. Compared to monocultures, 4-species
mixtures with both mycorrhizal types experienced significantly lower foliage
damage. The mixtures of EcM-species supported significantly higher predation
(i.e. a greater proportion of artificial caterpillars being attacked), and this effect
strengthened with tree species richness. The effects of tree species richness on
soil fauna feeding activity were negative across all mycorrhizal types in the lower
soil layer. Moreover, we showed that tree diversity effects were mediated by
above-ground tree biomass, vertical structural complexity and leaf quality, with
the dominating mechanisms largely depending on the mycorrhizal types.
4. Synthesis. Tree species richness affected multitrophic ecosystem functioning by
(1) directly decreasing the proportion of foliage damage in the communities with
both mycorrhizal types, where AM-species benefited from mixing with EcM-
species, and (2) increasing predation rates via changes in the vertical structural
complexity in mixtures of EcM-species. Our results highlight the importance of
considering mycorrhizal types for managing well-functioning mixed-species forests and contribute to broadening the mechanistic understanding of the context-
dependent BEF relationships in forests
An in vitro model system for testing chemical effects on microbiome-immune interactions: examples with BPX and PFAS mixtures
No full textIntroduction: More than 350,000 chemicals make up the chemical universe that surrounds us every day. The impact of this vast array of compounds on our health is still poorly understood. Manufacturers are required to carry out toxicological studies, for example on the reproductive or nervous systems, before putting a new substance on the market. However, toxicological safety does not exclude effects resulting from chronic exposure to low doses or effects on other potentially affected organ systems. This is the case for the microbiome-immune interaction, which is not yet included in any safety studies.
Methods: A high-throughput in vitro model was used to elucidate the potential effects of environmental chemicals and chemical mixtures on microbiome-immune interactions. Therefore, a simplified human intestinal microbiota (SIHUMIx) consisting of eight bacterial species was cultured in vitro in a bioreactor that partially mimics intestinal conditions. The bacteria were continuously exposed to mixtures of representative and widely distributed environmental chemicals, i.e. bisphenols (BPX) and/or per- and polyfluoroalkyl substances (PFAS) at concentrations of 22 µM and 4 µM, respectively. Furthermore, changes in the immunostimulatory potential of exposed microbes were investigated using a co-culture system with human peripheral blood mononuclear cells (PBMCs).
Results: The exposure to BPX, PFAS or their mixture did not influence the community structure and the riboflavin production of SIHUMIx in vitro. However, it altered the potential of the consortium to stimulate human immune cells: in particular, activation of CD8+ MAIT cells was affected by the exposure to BPX- and PFAS mixtures-treated bacteria.
Discussion: The present study provides a model to investigate how environmental chemicals can indirectly affect immune cells via exposed microbes. It contributes to the much-needed knowledge on the effects of EDCs on an organ system that has been little explored in this context, especially from the perspective of cumulative exposure
Adaptive optics retinal imaging in patients with usher syndrome
No full textPurpose: To determine the structure of the cone photoreceptor mosaic in the macula in eyes with retinitis pigmentosa related to Usher syndrome using adaptive optics fundus (AO) imaging and to correlate these findings with those of the standard clinical diagnostics.
Methods: Ten patients with a genetically confirmed retinitis pigmentosa in Usher syndrome due to biallelic variants in MYO7A or USH2A were enrolled in the study. All patients underwent a complete ophthalmological examination including best corrected visual acuity (BCVA), spectral-domain optical coherence tomography (SD-OCT) with fundus autofluorescence photography (FAF), full-field (ffERG) and multifocal electroretinography (mfERG) and Adaptive Optics Flood Illuminated Ophthalmoscopy (AO, rtx1™, Imagine Eyes, Orsay, France). The cone density was assessed centrally and at each 0.5 degree horizontally and vertically from 1–4 degree of eccentricity.
Results: In the AO images, photoreceptor cell death was visualized as a disruption of the cone mosaic and low cone density. In the early stage of the disease, cones were still visible in the fovea, whereas outside the fovea a loss of cones was recognizable by blurry, dark patches. The blurry patches corresponded to the parafoveal hypofluorescent ring in the FAF images and the beginning loss of the IS/OS line and external limiting membrane in the SD-OCT images. FfERGs were non-recordable in 7 patients and reduced in 3. The mfERG was reduced in all patients and correlated significantly (p <0.001) with the cone density. The kinetic visual field area, measured with III4e and I4e, did not correlate with the cone density.
Conclusion: The structure of the photoreceptors in Usher syndrome patients were detectable by AO fundus imaging. The approach of using high-resolution technique to assess the photoreceptor structure complements the established clinical examinations and allows a more sensitive monitoring of early stages of retinitis pigmentosa in Usher syndrome
Enhancing citizen science impact in environmental monitoring: Targeted engagement strategies with stakeholder groups
No full textUnderstanding the motivations and benefits of citizen science (CS) participants is critical to the success of environmental science projects that rely on data collection from engaged citizens. Tailored communication with citizen scientists is essential, leading to the need to target specific societal groups for extensive and high-quality data sets. The purpose of the study was to apply marketing concepts such as stakeholder analysis, value proposition canvas (VPC), and key performance indicators (KPIs) to CS projects. The study examined the extent to which these strategies can be applied to CS projects and add value, resulting in improved recruitment and retention of participants, as well as improved project management. The dynamic landscape of CS projects requires adapted business-oriented approaches supporting ongoing participation with high motivation, acknowledging community needs, and recognizing institutional scientists, akin to targeting potential customers. The case study focuses on the CityCLIM initiative, an EU-funded project collecting urban climate data, especially air temperature, using mobile weather stations. The CityCLIM VPC, analyzing stakeholder groups, facilitated tailored communication strategies by analyzing stakeholder groups and highlighting the effectiveness of the CS cycling initiative within the “Stadtradeln” program. Impact KPIs served as a roadmap for strategic refinement, while data quality KPIs identified deficiencies, guiding adjustments to the campaign. Applied marketing tools improved project planning, engagement, and evaluation, demonstrating the potential of this concept. Adapting marketing tools to recruitment and communication strategies benefits CS projects by targeting specific groups. The holistic integration of stakeholder analysis, VPC, and KPIs streamlines project management and creates a framework for sustainable success. This adaptation forms a robust toolkit for CS project coordinators, contributing to effective communication, engagement, and impact assessment. Applying marketing tools significantly increases CS projects’ reach and impact, ensuring long-term success and meaningful scientific contributions
Dysregulated cytokine and oxidative response in hyper-glycolytic monocytes in obesity
No full textIntroduction: Obesity is associated with a plethora of health complications, including increased susceptibility to infections or decreased vaccine efficacy, partly due to dysregulated immune responses. Monocytes play a crucial role in innate immunity, yet their functional alterations in obesity remain poorly understood.
Methods: Here, we employed proteomic and metabolomic analyses to investigate monocyte characteristics in individuals with overweight, obesity, impaired glucose tolerance (IGT), and type 2 diabetes (T2D), compared to lean donors.
Results and discussion: Our results revealed distinct molecular signatures in monocytes from individuals with obesity, with significant alterations in pathways related to metabolism, cellular migration, and phagocytosis. Moreover, LPS-induced activation of monocytes unveiled heightened metabolic reprogramming towards glycolysis in subjects with obesity accompanied by dysregulated cytokine responses and elevated oxidative stress. Additionally, monocytes from donors with obesity exhibited increased lipid droplet accumulation. These findings shed light on the immunometabolic dysregulation underlying obesity-associated immune dysfunction, highlighting potential targets for therapeutic intervention