The use of liquid metals based on gallium for soft and stretchable electronics is discussed. This emerging class of electronics is motivated, in part, by the new opportunities that arise from devices that have mechanical properties similar to those encountered in the human experience, such as skin, tissue, textiles, and clothing. These types of electronics (e.g., wearable or implantable electronics, sensors for soft robotics, e-skin) must operate during deformation. Liquid metals are compelling materials for these applications because, in principle, they are infinitely deformable while retaining metallic conductivity. Liquid metals have been used for stretchable wires and interconnects, reconfigurable antennas, soft sensors, self-healing circuits, and conformal electrodes. In contrast to Hg, liquid metals based on gallium have low toxicity and essentially no vapor pressure and are therefore considered safe to handle. Whereas most liquids bead up to minimize surface energy, the presence of a surface oxide on these metals makes it possible to pattern them into useful shapes using a variety of techniques, including fluidic injection and 3D printing. In addition to forming excellent conductors, these metals can be used actively to form memory devices, sensors, and diodes that are completely built from soft materials. The properties of these materials, their applications within soft and stretchable electronics, and future opportunities and challenges are considered.

Stretchable and Soft Electronics using Liquid Metals.

Muzeji su neformalna okruženja za ucenje, u kojima je ucenje istinski motivirano i procesirano preko znatiželje, promatranja i raznih aktivnosti. Proces takva ucenja može biti drugaciji od procesa ucenja koje vežemo uz formalna okruženja. Posebna prilika koju muzeji nude jest eksperimentalna priroda ucenja koja se temelji na susretima sa stvarnim objektima. U neformalnim okruženjima kognitivno i afektivno ucenje su povezani i mogu se nadograditi. Cilj ovog rada bio je istražiti stavove studenata o ucenju u muzeju, njegovoj ucinkovitosti i pozitivnim konotacijama na odgoj i obrazovanje djece. Istraživan je utjecaj varijable spola na oblikovanje stavova. U istraživanju je sudjelovalo 380 studenata, od toga 140 muskaraca i 240 žena. Studenti su visoko ocijenili znacaj takva nacina ucenja, smatraju ga ucinkovitim i potrebnim u odgoju i obrazovanju ucenika. Dobiveni rezultati trebali bi aktualizirati temu poticanja sveobuhvatnije suradnje muzeja i odgojno-obrazovnih ustanova.

/pdf/learning-at-the-museum-453avndrh2.pdf

Learning at the Museum

Affective Computing has emerged as an important field of study that aims to develop systems that can automatically recognize emotions. Up to the present, elicitation has been carried out with non-immersive stimuli. This study, on the other hand, aims to develop an emotion recognition system for affective states evoked through Immersive Virtual Environments. Four alternative virtual rooms were designed to elicit four possible arousal-valence combinations, as described in each quadrant of the Circumplex Model of Affects. An experiment involving the recording of the electroencephalography (EEG) and electrocardiography (ECG) of sixty participants was carried out. A set of features was extracted from these signals using various state-of-the-art metrics that quantify brain and cardiovascular linear and nonlinear dynamics, which were input into a Support Vector Machine classifier to predict the subject’s arousal and valence perception. The model’s accuracy was 75.00% along the arousal dimension and 71.21% along the valence dimension. Our findings validate the use of Immersive Virtual Environments to elicit and automatically recognize different emotional states from neural and cardiac dynamics; this development could have novel applications in fields as diverse as Architecture, Health, Education and Videogames.

/pdf/affective-computing-in-virtual-reality-emotion-recognition-106up9szl3.pdf

Affective computing in virtual reality: emotion recognition from brain and heartbeat dynamics using wearable sensors.

Background: Digital mental health interventions (DMHIs), which deliver mental health support via technologies such as mobile apps, can increase access to mental health support, and many studies have demonstrated their effectiveness in improving symptoms. However, user engagement varies, with regard to a user’s uptake and sustained interactions with these interventions.
Objective: This systematic review aims to identify common barriers and facilitators that influence user engagement with DMHIs.
Methods: A systematic search was conducted in the SCOPUS, PubMed, PsycINFO, Web of Science, and Cochrane Library databases. Empirical studies that report qualitative and/or quantitative data were included.
Results: A total of 208 articles met the inclusion criteria. The included articles used a variety of methodologies, including interviews, surveys, focus groups, workshops, field studies, and analysis of user reviews. Factors extracted for coding were related to the end user, the program or content offered by the intervention, and the technology and implementation environment. Common barriers included severe mental health issues that hampered engagement, technical issues, and a lack of personalization. Common facilitators were social connectedness facilitated by the intervention, increased insight into health, and a feeling of being in control of one’s own health.
Conclusions: Although previous research suggests that DMHIs can be useful in supporting mental health, contextual factors are important determinants of whether users actually engage with these interventions. The factors identified in this review can provide guidance when evaluating DMHIs to help explain and understand user engagement and can inform the design and development of new digital interventions.
Trial Registration:

/pdf/barriers-to-and-facilitators-of-user-engagement-with-digital-4p4iga4we6.pdf

Barriers to and Facilitators of User Engagement With Digital Mental Health Interventions: Systematic Review

Key Points
Astronauts have recently been discovered to have impaired vision, with a presentation that resembles syndromes of elevated intracranial pressure on Earth.
Gravity has a profound effect on fluid distribution and pressure within the human circulation. In contrast to prevailing theory, we observed that microgravity reduces central venous and intracranial pressure.
This being said, intracranial pressure is not reduced to the levels observed in the 90 deg seated upright posture on Earth. Thus, over 24 h in zero gravity, pressure in the brain is slightly above that observed on Earth, which may explain remodelling of the eye in astronauts.


Abstract
Astronauts have recently been discovered to have impaired vision, with a presentation that resembles syndromes of elevated intracranial pressure (ICP). This syndrome is considered the most mission-critical medical problem identified in the past decade of manned spaceflight. We recruited five men and three women who had an Ommaya reservoir inserted for the delivery of prophylactic CNS chemotherapy, but were free of their malignant disease for at least 1 year. ICP was assessed by placing a fluid-filled 25 gauge butterfly needle into the Ommaya reservoir. Subjects were studied in the upright and supine position, during acute zero gravity (parabolic flight) and prolonged simulated microgravity (6 deg head-down tilt bedrest). ICP was lower when seated in the 90 deg upright posture compared to lying supine (seated, 4 ± 1 vs. supine, 15 ± 2 mmHg). Whilst lying in the supine posture, central venous pressure (supine, 7 ± 3 vs. microgravity, 4 ± 2 mmHg) and ICP (supine, 17 ± 2 vs. microgravity, 13 ± 2 mmHg) were reduced in acute zero gravity, although not to the levels observed in the 90 deg seated upright posture on Earth. Prolonged periods of simulated microgravity did not cause progressive elevations in ICP (supine, 15 ± 2 vs. 24 h head-down tilt, 15 ± 4 mmHg). Complete removal of gravity does not pathologically elevate ICP but does prevent the normal lowering of ICP when upright. These findings suggest the human brain is protected by the daily circadian cycles in regional ICPs, without which pathology may occur.

https://physoc.onlinelibrary.wiley.com/doi/pdf/10.1113/JP273557

Effect of gravity and microgravity on intracranial pressure

INTRODUCTION Virtual reality (VR) can provide exposure to nature for those living in isolated confined environments We evaluated VR-presented natural settings for reducing stress and improving mood METHODS There were 18 participants (9 men, 9 women), ages 32 ± 12 yr, who viewed three 15-min 360° scenes (an indoor control, rural Ireland, and remote beaches) Subjects were mentally stressed with arithmetic before scenes Electrodermal activity (EDA) and heart rate variability measured psycho-physiological arousal The Positive and Negative Affect Schedule and the 15-question Modified Reality Judgment and Presence Questionnaire (MRJPQ) measured mood and scene quality RESULTS Reductions in EDA from baseline were greater at the end of the natural scenes compared to the control scene (-059, -052, and 032 μS, respectively) The natural scenes reduced negative affect from baseline ( 12 and 11 points), but the control scene did not ( 04 points) MRJPQ scores for the control scene were lower than both natural scenes (49, 67, and 65 points, respectively) Within the two natural scenes, the preferred scene reduced negative affect ( 24 points) more than the second choice scene ( 18 points) and scored higher on the MRJPQ (68 vs 64 points) DISCUSSION Natural scene VR provided relaxation both objectively and subjectively, and scene preference had a significant effect on mood and perception of scene quality VR may enable relaxation for people living in isolated confined environments, particularly when matched to personal preferencesAnderson AP, Mayer MD, Fellows AM, Cowan DR, Hegel MT, Buckey JC Relaxation with immersive natural scenes presented using virtual reality Aerosp Med Hum Perform 2017; 88(6):520526

Relaxation with Immersive Natural Scenes Presented Using Virtual Reality.

Wearable health-monitoring systems should be comfortable, non-stigmatizing, and able to achieve high data quality. Smart textiles with electronic elements integrated directly into fabrics offer a way to embed sensors into clothing seamlessly to serve these purposes. In this work, we demonstrate the feasibility of electrocardiogram (ECG) monitoring with sewn textile electrodes instead of traditional gel electrodes in a 3-lead, chest-mounted configuration. The textile electrodes are sewn with silver-coated thread in an overlapping zig zag pattern into an inextensible fabric. Sensor validation included ECG monitoring and comfort surveys with human subjects, stretch testing, and wash cycling. The electrodes were tested with the BIOPAC MP160 ECG data acquisition module. Sensors were placed on 8 subjects (5 males and 3 females) with double-sided tape. To detect differences in R peak detectability between traditional and sewn sensors, effect size was set at 10% of a sample mean for heart rate (HR) and R-R interval. Paired student’s t-tests were run between adhesive and sewn electrode data for R-R interval and average HR, and a Wilcoxon signed-rank test was run for comfort. No statistically significant difference was found between the traditional and textile electrodes (R-R interval: t = 1.43, p > 0.1; HR: t = −0.70, p > 0.5; comfort: V = 15, p > 0.5).

https://www.mdpi.com/1424-8220/20/4/1013/pdf

Textile Electrocardiogram (ECG) Electrodes for Wearable Health Monitoring

Intraocular pressure (IOP) initially increases when an individual enters microgravity compared with baseline values when an individual is in a seated position. This has been attributed to a headward fluid shift that increases venous pressures in the head. The change in IOP exceeds changes measured immediately after moving from seated to supine postures on Earth, when a similar fluid shift is produced. Furthermore, central venous and cerebrospinal fluid pressures are at or below supine position levels when measured initially upon entering microgravity, unlike when moving from seated to supine postures on Earth, when these pressures increase. To investigate the effects of altering gravitational forces on the eye, we made ocular measurements on 24 subjects (13 men, 11 women) in the seated, supine, and prone positions in the laboratory, and upon entering microgravity during parabolic flight. IOP in microgravity (16.3 ± 2.7 mmHg) was significantly elevated above values in the seated (11.5 ± 2.0 mmHg) and supine (13.7 ± 3.0 mmHg) positions, and was significantly less than pressure in the prone position (20.3 ± 2.6 mmHg). In all measurements,P< 0.001. Choroidal area was significantly increased in subjects in a microgravity environment (P< 0.007) compared with values from subjects in seated (increase of 0.09 ± 0.1 mm(2)) and supine (increase of 0.06 ± 0.09 mm(2)) positions. IOP results are consistent with the hypothesis that hydrostatic gradients affect IOP, and may explain how IOP can increase beyond supine values in microgravity when central venous and intracranial pressure do not. Understanding gravitational effects on the eye may help develop hypotheses for how microgravity-induced visual changes develop.

Acute effects of changes to the gravitational vector on the eye.

On Earth, tissue weight generates compressive forces that press on body structures and act on the walls of vessels throughout the body. In microgravity, tissues no longer have weight, and tissue co...

Microgravity-induced ocular changes are related to body weight

While craft has had increasing influence on HCI research, HCI researchers tend to engage craft in limited capacities, often focusing on the juxtapositions of "traditional" craft and "innovative" computing. In this paper, we describe the structure and results of a six-week "experimental weaving residency" to show how HCI practitioners, engineers, and craftspeople perform similar work and can productively collaborate to envision new technological interfaces at early stages of development. We address both social and technical challenges of residencies and critically reflect on biases about technical and craft labor that we held prior to the residency. We share our experiences and lessons learned in the hopes of supporting future collaborations with craftspeople and broadening the techniques we use to address design challenges.

Allison P. Anderson

Papers

Relaxation with Immersive Natural Scenes Presented Using Virtual Reality.

Textile Electrocardiogram (ECG) Electrodes for Wearable Health Monitoring

Acute effects of changes to the gravitational vector on the eye.

Microgravity-induced ocular changes are related to body weight

Craftspeople as Technical Collaborators: Lessons Learned through an Experimental Weaving Residency