The Mood Game - How to use the player’s affective state in a shoot’em up avoiding frustration and boredom

In this demo paper, we present a shoot'em up game similar to Space Invaders called the "Mood Game" that incorporates players' affective state into the game mechanics in order to enhance the gaming experience and avoid undesired emotions like frustration and boredom. By tracking emotions through facial expressions combined with self-evaluation, keystrokes and performance measures, we have developed a game logic that adapts the playing difficulty based on the player's emotional state. The implemented algorithm automatically adjusts the enemy spawn rate and enemy behavior, the amount of obstacles, the number and type of power ups and the game speed to provide a smooth game play for different player skills. The effects of our dynamic game balancing mechanism will be tested in future work

SARS-CoV-2 T Cell Response in Severe and Fatal COVID-19 in Primary Antibody Deficiency Patients Without Specific Humoral Immunity

Morbidity and mortality of COVID-19 is increased in patients with inborn errors of immunity (IEI). Age and comorbidities and also impaired type I interferon immunity were identified as relevant risk factors. In patients with primary antibody deficiency (PAD) and lack of specific humoral immune response to SARS-CoV-2, clinical disease outcome is very heterogeneous. Despite extensive clinical reports, underlying immunological mechanisms are poorly characterized and levels of T cellular and innate immunity in severe cases remain to be determined. In the present study, we report clinical and immunological findings of 5 PAD patients with severe and fatal COVID-19 and undetectable specific humoral immune response to SARS-CoV-2. Reactive T cells to SARS-CoV-2 spike (S) and nucleocapsid (NCAP) peptide pools were analyzed comparatively by flow cytometry in PAD patients, convalescents and naive healthy individuals. All examined PAD patients developed a robust T cell response. The presence of polyfunctional cytokine producing activated CD4(+) T cells indicates a memory-like phenotype. An analysis of innate immune response revealed elevated CD169 (SIGLEC1) expression on monocytes, a surrogate marker for type I interferon response, and presence of type I interferon autoantibodies was excluded. SARS-CoV-2 RNA was detectable in peripheral blood in three severe COVID-19 patients with PAD. Viral clearance in blood was observed after treatment with COVID-19 convalescent plasma/monoclonal antibody administration. However, prolonged mucosal viral shedding was observed in all patients (median 67 days) with maximum duration of 127 days. PAD patients without specific humoral SARS-CoV-2 immunity may suffer from severe or fatal COVID-19 despite robust T cell and normal innate immune response. Intensified monitoring for long persistence of SARS-CoV-2 viral shedding and (prophylactic) convalescent plasma/specific IgG as beneficial treatment option in severe cases with RNAemia should be considered in seronegative PAD patients

The 14-3-3ζ Protein Binds to the Cell Adhesion Molecule L1, Promotes L1 Phosphorylation by CKII and Influences L1-Dependent Neurite Outgrowth

BACKGROUND: The cell adhesion molecule L1 is crucial for mammalian nervous system development. L1 acts as a mediator of signaling events through its intracellular domain, which comprises a putative binding site for 14-3-3 proteins. These regulators of diverse cellular processes are abundant in the brain and preferentially expressed by neurons. In this study, we investigated whether L1 interacts with 14-3-3 proteins, how this interaction is mediated, and whether 14-3-3 proteins influence the function of L1. METHODOLOGY/PRINCIPAL FINDINGS: By immunoprecipitation, we demonstrated that 14-3-3 proteins are associated with L1 in mouse brain. The site of 14-3-3 interaction in the L1 intracellular domain (L1ICD), which was identified by site-directed mutagenesis and direct binding assays, is phosphorylated by casein kinase II (CKII), and CKII phosphorylation of the L1ICD enhances binding of the 14-3-3 zeta isoform (14-3-3ζ). Interestingly, in an in vitro phosphorylation assay, 14-3-3ζ promoted CKII-dependent phosphorylation of the L1ICD. Given that L1 phosphorylation by CKII has been implicated in L1-triggered axonal elongation, we investigated the influence of 14-3-3ζ on L1-dependent neurite outgrowth. We found that expression of a mutated form of 14-3-3ζ, which impairs interactions of 14-3-3ζ with its binding partners, stimulated neurite elongation from cultured rat hippocampal neurons, supporting a functional connection between L1 and 14-3-3ζ. CONCLUSIONS/SIGNIFICANCE: Our results suggest that 14-3-3ζ, a novel direct binding partner of the L1ICD, promotes L1 phosphorylation by CKII in the central nervous system, and regulates neurite outgrowth, an important biological process triggered by L1

PumpVR: Rendering the Weight of Objects and Avatars through Liquid Mass Transfer in Virtual Reality

Perceiving objects’ and avatars’ weight in Virtual Reality (VR) is important to understand their properties and naturally interact with them. However, commercial VR controllers cannot render weight. Controllers presented by previous work are single-handed, slow, or only render a small mass. In this paper, we present PumpVR that renders weight by varying the controllers’ mass according to the properties of virtual objects or bodies. Using a bi-directional pump and solenoid valves, the system changes the controllers’ absolute weight by transferring water in or out with an average error of less than 5. We implemented VR use cases with objects and avatars of different weights to compare the system with standard controllers. A study with 24 participants revealed significantly higher realism and enjoyment when using PumpVR to interact with virtual objects. Using the system to render body weight had significant effects on virtual embodiment, perceived exertion, and self-perceived fitness

How to Induce a Physical and Virtual Rubber Hand Illusion

Understanding body ownership is essential when creating virtual reality (VR) applications using avatars. One of the most widely-used paradigm to investigate body ownership is the rubber hand illusion (RHI). When a real hand and a rubber hand are stroked synchronously, participants can experience the rubber hand as their own hand. Although the knowledge from RHI experiments in the real world is applied to when users embody avatars in VR, it is still unclear whether the illusory ownership of a virtual and physical body produce the same effects. In addition, conducting RHI studies in VR would allow gaining a range of novel experiments that are not possible in the real world. With this demonstration, we therefore present a system and approach to investigate the RHI in the real world and in VR

Understanding the Effects of Perceived Avatar Appearance on Latency Sensitivity in Full-Body Motion-Tracked Virtual Reality

Latency in virtual reality (VR) can decrease the feeling of presence and body ownership. How users perceive latency, however, is plastic and affected by the design of the virtual content. Previous work found that an avatar's visual appearance, particularly its perceived fitness, can be leveraged to change user perception and behavior. Moreover, previous work investigating non-VR video games also demonstrated that controlling avatars that visually conform to users' expectations associated with the avatars' perceived characteristics increases the users' latency tolerance. However, it is currently unknown if the avatar's visual appearance can be used to modulate the users' latency sensitivity in full-body motion-tracked VR. Therefore, we conducted two studies to investigate if the avatars' appearance can be used to decrease the negative impact of latency. In the first study, 41 participants systematically determined two sets of avatars whose visual appearance is perceived to be more or less fit in two physically challenging tasks. In a second study (N = 16), we tested the two previously determined avatars (perceived to be more fit vs. perceived to be less fit) in the two tasks using VR with two levels of controlled latency (system vs. high). We found that embodying an avatar perceived as more fit significantly increases the participants' physical performance, body ownership, presence, and intrinsic motivation. While we show that latency negatively affects performance, our results also suggest that the avatar's visual appearance does not alter the effects of latency in VR

16. Workshop Be-greifbare Interaktion

Tangible interaction is centered around the manipulation of physical objects and the usage of the own body. It thus involves the environment and the physical context much stronger than purely visual or speech-based interfaces. The wide range of possibilities for integrating sensors and computing systems into the physical environment provides ample design space. The research field of Tangible Interaction investigates this scope scientifically and practically in order to enable meaningful and human-oriented applications. In this workshop, the German Informatics Society (GI) specialist group "Be-greifbare Interaktion" of the Department of Human-Computer Interaction offers a forum for the presentation of scientific discourse and interdisciplinary discussion. Contributions range from theoretical, critical and forward-looking reflections to design work and reports on practical implementations. The workshop opens the discussion to a broader audience of experts in order to disclose current developments and generate new impulses for the research field