Effects of stereo viewing conditions on distance perception in virtual environments

technical reportSeveral studies from different research groups investigating perception of absolute, egocentric distances in virtual environments have reported a compression of the intended size of the virtual space. One potential explanation for the compression is that inaccuracies and cue confliicts involving stereo viewing conditions in head-mounted displays result in an inaccurate absolute scaling of the virtual world. We manipulate stereo viewing conditions in a head-mounted display and show the effects of using both measured and fixed interpupilary distances, as well as bi-ocular and monocular viewing of graphics, on absolute distance judgments. Our results indicate that the limitations on the presentation of stereo imagery that are inherent in head-mounted displays are likely not the source of distance compression reported in previous virtual environment studies

An experimental comparison of perceived egocentric distance in real, image-based, and traditional virtual environment using direct walking tasks

technical reportIn virtual environments, perceived egocentric distances are often underestimated when compared to the same distance judgments in the real world. The research presented in this paper explores two possible causes for this reduced distance perception in virtual environments: (1) real-time computer graphics rendering, and (2) immersive display technology. Our experiment compared egocentric distance judgments in three complex, indoor environments: a real hallway with full-cue conditions; a virtual, stereoscopic, photographic panorama; and a virtual, stereoscopic computer model. Perceived egocentric distance was determined by a directed walking task in which subjects walk blindfolded to the target. Our results show there is a significant difference in distance judgments between real and virtual environments. However, the differences between distance judgments in virtual photographic panorama environments and traditionally rendered virtual environments are small, suggesting that the display device is affecting distance judgments in virtual environments

Exploring the dimensionality of fear of missing out: Associations with related constructs

A growing body of research has examined the potential effects of the Fear of Missing Out (FoMO) whereby the Fear of Missing Out Scale (FoMOs; Przybylski et al., 2013) has become the most popular measure for assessing the construct. However, there is ambiguity regarding FoMO’s conceptualization and dimensionality. Employing a large representative sample (N = 2,041), this study provides direct empirical support for the conceptualization of FoMO as a second-order construct with two underlying dimensions, i.e., “pervasive apprehension” and “desire for connection”, each with distinct relations with variables that have been theoretically linked with FoMO. More specifically, problematic social media use, deficits in needs satisfaction, and neuroticism are more strongly correlated with “pervasive apprehension”, while social media use and extraversion are more strongly correlated with “desire for connection”. As such, this study contributes to future research as it offers a new perspective on the FoMO construct by showing the importance of giving adequate consideration (statistically and conceptually) to the structure of the construct and how the two dimensions relate to other constructs of interest

The Idea of Precaution: Ethical Requirements for the Regulation of New Biotechnologies in the Environmental Field

The rapid emergence of new biotechnologies for selectively altering genetic material—so-called genome editing—has sparked public controversy about how their development and application in the environmental fields are to be regulated. Since the use of these new technologies harbors not only considerable potential but also risks of serious damage whose occurrence is uncertain due to their application in complex environmental systems, many national and international legal authorities are currently adhering to policies of precaution. According to critics, however, precautionary measures and the legal principle of precaution on which they are based are unduly restrictive in the case of the new biotechnologies, hindering advancements in both research and various fields of application. At the same time, legal notions of precaution are highly ambiguous within and across different national and international formulations, thereby further complicating the controversy about their implications. This paper goes beyond the concept of precaution as found in environmental law by examining the ethical significance and the ethical justification of precautionary measures in the environmental field. In particular, it clarifies the criterion of potential damage, disambiguates different types of epistemic bases in precaution decisions, and considers the relevance and implications of different ethical risk theories as to their response to epistemic uncertainty and vagueness. The two main conclusions are that, first, irrespective of the ethical risk theory embraced, there is an ethical obligation to take precautionary measures whenever serious damage is possible and the probability of damage occurring epistemically uncertain or vague. Regarding the risk assessment, it is argued that the burden of proof lies not with those who fear the occurrence of serious environmental damage. Rather, it is up to those whose actions give rise to such fears to demonstrate that serious damage is extremely improbable or scientifically absurd. Second, the moral responsibility to determine precaution situations and to specify appropriate precautionary measures is attributed not only to state authorities but also to industrial players as well as research communities. Based on these two conclusions, recommendations are given as to how the precautionary principle should be incorporated in political and legal decision-making

Joint Workshop on Interfaces and Human Decision Making for Recommender Systems (IntRS’21)

Recommender systems were originally developed as interactive intelligent systems that can proactively guide users to items that match their preferences. Despite its origin on the crossroads of HCI and AI, the majority of research on recommender systems gradually focused on objective accuracy criteria paying less and less attention to how users interact with the system as well as the efficacy of interface designs from users’ perspectives. This trend is reversing with the increased volume of research that looks beyond algorithms, into users’ interactions, decision making processes, and overall experience. The series of workshops on Interfaces and Human Decision Making for Recommender Systems focuses on the "human side" of recommender systems. The goal of the research stream featured at the workshop is to improve users’ overall experience with recommender systems by integrating different theories of human decision making into the construction of recommender systems and exploring better interfaces for recommender systems. In this summary,we introduce the JointWorkshop on Interfaces and Human Decision Making for Recommender Systems at RecSys’21, review its history, and discuss most important topics considered at the workshop

Propofol for endotracheal intubation in neonates: A dose-finding trial

Objective: To find propofol doses providing effective sedation without side effects in neonates of different gestational ages (GA) and postnatal ages (PNA). Design and setting: Prospective multicentere dose-finding study in 3 neonatal intensive care units. Patients: Neonates with a PNA <28 days requiring non-emergency endotracheal intubation. Interventions: Neonates were stratified into 8 groups based on GA and PNA. The first 5 neonates in every group received a dose of 1.0 mg/kg propofol. Based on sedative effect and side effects, the dose was increased or decreased in the next 5 patients until the optimal dose was found. Main outcome measures: The primary outcome was the optimal single propofol starting dose that provides effective sedation without side effects in each age group. Results: After inclusion of 91 patients, the study was prematurely terminated because the primary outcome was only reached in 13% of patients. Dose-finding was completed in 2 groups, but no optimal propofol dose was found. Effective sedation without side effects was achieved more often after a starting dose of 2.0 mg/kg (28%) than after 1.0 mg/kg (3%) and 1.5 mg/kg (9%). Propofol-induced hypotens

Males do not reduce the fitness of their female co-twins in contemporary samples.

Lummaa et al. (2007) presented historical data collected from twins born in Finland between 1734 and 1888 which suggested that females (N = 31) born as part of an opposite sex (OS) twin pair were 25% less likely to reproduce than female twins (N = 35) born as part of a same sex (SS) pair. They hypothesized that this reduction in fitness was due to masculinization of the female fetus via prenatal effects of the hormones of a male fetus. Because such masculinization would presumably take place in modern populations as well, it would seem important to establish to what degree it does so, and if so, whether reproduction is affected. We therefore address the question of reproduction differences in individual female twins from same-sex (N = 1979) and opposite-sex (N = 913) dizygotic pairs in studies carried out in Australia, the Netherlands, and the United States. In all three samples, there were no differences in the number of children or age of first pregnancies in women from same sex pairs compared to those from opposite sex pairs. Similarly, there were no differences in psychological femininity between women from pairs of the same or opposite sex

Experimental evolution of pseudogenization and gene loss in a plant RNA virus

[EN] Viruses have evolved highly streamlined genomes and a variety of mechanisms to compress them, suggesting that genome size is under strong selection. Horizontal gene transfer has, on the other hand, played an important role in virus evolution. However, evolution cannot integrate initially nonfunctional sequences into the viral genome if they are rapidly purged by selection. Here we report on the experimental evolution of pseudogenization in virus genomes using a plant RNA virus expressing a heterologous gene. When long 9-week passages were performed, the added gene was lost in all lineages, whereas viruses with large genomic deletions were fixed in only two out of ten 3-week lineages and none in 1-week lineages. Illumina next-generation sequencing revealed considerable convergent evolution in the 9- and 3-week lineages with genomic deletions. Genome size was correlated to within-host competitive fitness, although there was no correlation with virus accumulation or virulence. Within-host competitive fitness of the 3-week virus lineages without genomic deletions was higher than for the 1-week lineages. Our results show that the strength of selection for a reduced genome size and the rate of pseudogenization depend on demographic conditions. Moreover, for the 3-week passage condition, we observed increases in within-host fitness, whereas selection was not strong enough to quickly remove the nonfunctional heterologous gene. These results suggest a demographically determined "sweet spot" might exist, where heterologous insertions are not immediately lost while evolution can act to integrate them into the viral genome.The authors thank Alejandro Manzano Marin for his bioinformatics guidance with the Illumina analysis and Francisca de la Iglesia, Paula Agudo, and Angels Prosper for technical support. This project was made possible through the support of grant 22371 from the John Templeton Foundation to S. F. E. The opinions expressed in this publication are those of the authors and do not necessarily reflect the views of John Templeton Foundation. Additional support was received from the Spanish Direccion General de Investigacion Cientifica y Tecnica grants BFU2012-30805 to S. F. E, JCI2011-10379 to M.P.Z, and BIO2011-26741 to J.A.D., and by a Rubicon grant from the Netherlands Organization for Scientific Research (www.nwo.nl) to M.P.Z.Zwart, MP.; Willemsen, A.; Daros Arnau, JA.; Elena Fito, SF. (2014). Experimental evolution of pseudogenization and gene loss in a plant RNA virus. Molecular Biology and Evolution. 31(1):121-134. https://doi.org/10.1093/molbev/mst175S12113431