Abstract
Virtual Reality (VR) has opened avenues for users to immerse themselves in virtual 3D environments, simulating reality across various domains like health, education, and entertainment. Haptic feedback plays a pivotal role in achieving lifelike experiences. However, the accessibility of haptic devices poses challenges, prompting the exploration of alternatives. In response, Pseudo-Haptic feedback has emerged, utilizing visual and auditory cues to create illusions or modify perceived haptic feedback. Given that many pseudo-haptic techniques are yet to be tailored for VR, our proposal involves combining and adapting multiple techniques to enhance compliance perception in virtual environments. By modifying the Mass-Spring-Damper model and incorporating hand-tracking software along with an inverse kinematics algorithm, our aim is to deliver compliance feedback through visual stimuli, thereby elevating the realism of the overall experience. The outcomes were encouraging, with numerous participants expressing their ability to easily discern various compliance levels with high confidence, all within a realistic and immersive environment. Additionally, we observed an impact of object scale on the perception of compliance in specific scenarios, as participants noted a tendency to perceive smaller objects as more compliant.

Abstract
DeskVR allows users to experience Virtual Reality (VR) while sitting at a desk without requiring extensive movements. This makes it better suited for professional work environments where productivity over extended periods is essential. However, tasks that typically resort to mid-air gestures might not be suitable for DeskVR. In this paper, we focus on the fundamental task of object selection. We present TouchRay, an object selection technique conceived specifically for DeskVR that enables users to select objects at any distance while resting their hands on the desk. It also allows selecting objects' sub-components by traversing their corresponding hierarchical trees. We conducted a user evaluation comparing TouchRay against state-of-the-art techniques targeted at traditional VR. Results revealed that participants could successfully select objects in different settings, with consistent times and on par with the baseline techniques in complex tasks, without requiring mid-air gestures.

Abstract
Virtual reality (VR) has the potential to significantly boost productivity in professional settings, especially those that can benefit from immersive environments that allow a better and more thorough way of visualizing information. However, the physical demands of mid-air movements make it difficult to use VR for extended periods. DeskVR offers a solution that allows users to engage in VR while seated at a desk, minimizing physical exhaustion. However, developing appropriate motion techniques for this context is challenging due to limited mobility and space constraints. This work focuses on object manipulation techniques, exploring touch-based and mid-air-based approaches to design a suitable solution for DeskVR, hypothesizing that touch-based object manipulation techniques could be as effective as mid-air object manipulation in a DeskVR scenario while less physically demanding. Thus, we propose Scaled Indirect Touch 6-DOF (SIT6), an indirect touch-based object manipulation technique incorporating scaled input mapping to address precision and out-of-reach manipulation issues. The implementation of our solution consists of a state machine with error-handling mechanisms and visual indicators to enhance interaction. User experiments were conducted to compare the SIT6 technique with a baseline mid-air approach, revealing comparable effectiveness while demanding less physical exertion. These results validated our hypothesis and established SIT6 as a viable option for object manipulation in DeskVR scenarios. (c) 2023 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Abstract
Haptic feedback in Virtual Reality is commonly provided through wearable or grounded devices adapted to specific scenarios and situations. Shape-changing devices allow for the physical representation of different virtual objects but are still a minority, complex, and usually have long transformation times. We present Shape-a-getti, a novel ungrounded, non-wearable, and graspable haptic device that can quickly change between different radially symmetrical shapes. It uses a single actuator to rotate several identical poles distributed along a radius to render the different shapes. The format of the poles defines the possible shapes, and in our prototype, we used one that could render concave, straight, and convex shapes with different radii. We conducted a user evaluation with 21 participants asking them to recognize virtual objects by grasping the Shape-a-getti. Despite having difficulties distinguishing between some objects with very similar shapes, participants could successfully identify virtual objects with different shapes rendered by our device. (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

Abstract
ObjectivesThere is a growing interest in mindfulness-based programs. Yet, research in the area is limited, and little is known about the factors that moderate the effects of these programs. The two-fold aim of this study was (1) to examine the effects of a mindfulness-based program on dispositional mindfulness, inattention and emotional lability, handwriting fluency, spelling accuracy, and composing quality, as well as school achievement; and (2) to evaluate the moderating role of lesson absences, intervention-related knowledge, and social validity.MethodUsing a quasi-experimental design, 257 fourth graders were assigned to an experimental group receiving a mindfulness-based program (n = 130) or an active control group receiving a health-based program (n = 127). Both programs were implemented in the classroom for 8 weekly units, which included two 30-min sessions delivered by psychologists, followed by three 5-min sessions delivered by teachers. All children were evaluated before and after the programs.ResultsCompared to the control condition, the mindfulness-based program resulted in higher levels of internal and external awareness, and decentering and nonreactivity, as well as better composing quality and mathematics grades. Lesson absences, intervention-related knowledge, and social validity did not moderate the effects of the mindfulness-based program.ConclusionsThese findings support the integration of mindfulness practices in primary school as a means to improve children's academic-related skills and ability to be mindful.

Abstract
This paper presents a robust approach for 3D point reconstruction based on a set of images taken from a static scene with known. but not necessarily exact or regular, camera parameters. The points to be reconstructed are chosen from the contours of images, and a world-based formulation of the reconstruction problem and associated epipolar geometry is used. The result is a powerful mean of transparently integrating contributions from multiple images, and increased robustness to situations such as occlusions or apparent contours. Two steps for adding robustness are proposed: cross-checking, which validates a reconstructed point taken from an image by projecting it on a special subset of the remaining images; and merging, which fuses pairs of reconstructed points that are close in 3D space and that were initially chosen from different images. Results obtained with a synthetic scene (for ground truth comparison and error assessment), and two real scenes show the improved robustness achieved with the steps proposed.