| 1. |
- Arzoumanian, Doris, et al.
(författare)
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Dust polarized emission observations of NGC 6334: BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network
- 2021
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 647
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Tidskriftsartikel (refereegranskat)abstract
- Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density and velocity structures of both filaments and hubs have been carefully studied, their magnetic field (B-field) properties have yet to be characterized. Consequently, the role of B-fields in the formation and evolution of hub-filament systems is not well constrained. Aims. We aim to understand the role of the B-field and its interplay with turbulence and gravity in the dynamical evolution of the NGC 6334 filament network that harbours cluster-forming hubs and high-mass star formation. Methods. We present new observations of the dust polarized emission at 850 μm toward the 2 pc × 10 pc map of NGC 6334 at a spatial resolution of 0.09 pc obtained with the James Clerk Maxwell Telescope (JCMT) as part of the B-field In STar-forming Region Observations (BISTRO) survey. We study the distribution and dispersion of the polarized intensity (PI), the polarization fraction (PF), and the plane-of-The-sky B-field angle (χB_POS) toward the whole region, along the 10 pc-long ridge and along the sub-filaments connected to the ridge and the hubs. We derived the power spectra of the intensity and χBPOS along the ridge crest and compared them with the results obtained from simulated filaments. Results. The observations span 3 orders of magnitude in Stokes I and PI and 2 orders of magnitude in PF (from 0.2 to 20%). A large scatter in PI and PF is observed for a given value of I. Our analyses show a complex B-field structure when observed over the whole region ( 10 pc); however, at smaller scales (1 pc), χBPOS varies coherently along the crests of the filament network. The observed power spectrum of χBPOS can be well represented with a power law function with a slope of-1.33 ± 0.23, which is 20% shallower than that of I. We find that this result is compatible with the properties of simulated filaments and may indicate the physical processes at play in the formation and evolution of star-forming filaments. Along the sub-filaments, χBPOS rotates frombeing mostly perpendicular or randomly oriented with respect to the crests to mostly parallel as the sub-filaments merge with the ridge and hubs. This variation of the B-field structure along the sub-filaments may be tracing local velocity flows of infalling matter in the ridge and hubs. Our analysis also suggests a variation in the energy balance along the crests of these sub-filaments, from magnetically critical or supercritical at their far ends to magnetically subcritical near the ridge and hubs. We also detect an increase in PF toward the high-column density (NH2 â 1023 cm-2) star cluster-forming hubs. These latter large PF values may be explained by the increase in grain alignment efficiency due to stellar radiation from the newborn stars, combined with an ordered B-field structure. Conclusions. These observational results reveal for the first time the characteristics of the small-scale (down to 0.1 pc) B-field structure of a 10 pc-long hub-filament system. Our analyses show variations in the polarization properties along the sub-filaments that may be tracing the evolution of their physical properties during their interaction with the ridge and hubs. We also detect an impact of feedback from young high-mass stars on the local B-field structure and the polarization properties, which could put constraints on possible models for dust grain alignment and provide important hints as to the interplay between the star formation activity and interstellar B-fields.
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| 2. |
- Backlund, Per, 1964-, et al.
(författare)
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Teaching cardiovascular health through a purposeful game
- 2022
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Ingår i: Collection of materials: II International Scientific and Practical Internet Conference "Innovative Solutions in Economy, Business, Public Communications and International Relationships", April 21, 2022, Dnipro. - Dnipro : Університет митної справи та фінансів / Universytet mytnoyi spravy ta finansiv. ; , s. 391-396
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Games for health is one of the most prominent areas for serious games, i.e. games with a purpose beyond only entertainment. The purpose of a health game may be to inform about health related issues; promote healthy lifestyles and even to drive behavioral change. This paper outlines the initial game design considerations and some future research directions for a game focusing on cardiovascular health. As the overall aim of the project is to promote a healthy lifestyle through diet and physical activity to prevent future cardiovascular disease, we focused on “taking care of your heart” as the basis for the game. Hence we call the game Happy Heart and use a heart symbol as a non-playable character (NPC) that the player needs to take care of. To some extent we are inspired by the electronic Tamagochi toys (Bandai) where players need to take care of a digital pet. The heart symbol is universal and is also an ideograph that expresses the concept of love and as such it transcends language barriers.The burden of non-communicable diseases (NCD) is rapidly increasing across the world. Today they are the main drivers of morbidity, disability, and mortality in low- and middle income countries (LMICs), and are expected to increase due to unhealthy lifestyles in the wake of ongoing societal changes [1]. Among the major risk factors in many LMICs are poor diet, insufficient physical activity, tobacco and alcohol consumption, and exposure to hazardous substances, e.g. from air pollution. LMICs currently contribute three quarters of the deaths from NCD.Among the NCD, cardiovascular diseases are the most common cause of hospitalization in Nepal [1]. Digitalization and collaboration with the education sector (e.g. community schools) in health promotion interventions could further improve children’s behavior by targeting factors that affect their lifestyle outside the family environment [4]. Hence, the Digital Game Based Learning approach.
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| 3. |
- Bai, Hua, 1990-, et al.
(författare)
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A Model for Balancing Clarity and Appeal in Serious Game Visuals
- 2023
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Ingår i: Proceedings of the 17th European Conference on Games Based Learning. - : Academic Conferences International Limited. - 9781914587887 - 9781914587894 ; , s. 46-52
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Konferensbidrag (refereegranskat)abstract
- In serious game development, graphic design needs to be eye-catching, while also depicting subject matter content in a responsible, accurate, and clear way. Previous research has shown that abstract and symbolic game visuals seem to be preferable for learning and providing an engaging experience. Our research focuses on describing the challenges involved in creating effective visual communication through game graphics in cross cultures. In particular, we’re interested in examining if certain styles of visual communication are more or less effective between different cultural demographics. To examine this, we have created a serious game which aims to promote healthy food and nutrition habits to teenagers in both Nepalese and Swedish schools and by doing so also motivate behavioral changes toward healthier eating habits. We are currently conducting studies to see whether preferences and image recognition differ between the two demographical spheres. This paper will only discuss the exploratory study done in Nepal. Ultimately, this paper aims to contribute development guidelines that can aid developers in creating more effective visual communication in their serious games, and we primarily focus on exploring what we call the compromise of ‘clarity’ and ‘appeal’ in the creation of game graphics. We present an initial model for choosing at what level in terms of realism/abstraction and taxonomic hierarchy the graphical components of serious games optimally should be produced in order to solve the dilemma of precise, unmistakable, yet appealing visuals in serious games. It all comes down to two primary decisions: defining the taxonomic hierarchy of the items to depict, and choosing the style in which to depict them. With a better understanding of when different game visuals are more or less appropriate, both in terms of style and in which objects are represented, game developers will be able to balance production costs better while also creating something that strikes the compromise between clarity and appeal.
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| 4. |
- Bai, Hua, 1990-, et al.
(författare)
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An Exploratory Study on Nepalese Teenager’s Visual Recognition and Preferences in Serious Games
- 2022
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Ingår i: Proceedings 2022 IEEE International Conference on e-Business Engineering ICEBE 2022. - : IEEE Computer Society. - 9781665492447 - 9781665492454 ; , s. 13-18
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Konferensbidrag (refereegranskat)abstract
- In serious game development, effective communication through both languages, sounds, and icons can be crucial for a game to have its intended impact. While this is also true for entertainment games, serious games have added layers of challenges as they are a) often played by audiences outside of the “typical” game ecosystem, and b) miscommunication can lead to players missing important lessons or even learning incorrect information. When a serious game is intended to be used in different parts of the world, however, clear visual communication gets an added layer of complexity: culturally informed symbol interpretation and visual preference. In order to examine how these might affect players’ experiences when playing serious games, this paper presents the results of a mixed-method study conducted in two schools in Nepal. The study included 10 participants, between 13-16 years old, who played a prototype of a mobile game currently in development, which has the purpose of teaching young players about food nutrition and healthy habits. After playing the prototype, they took a short survey where they were asked to identify different food types, and they were also interviewed to discuss their opinions of the game’s visual style. The results of the study indicate that, while higher fidelity images were much easier to correctly identify by the participants, the participants’ preference for visual fidelity varied to a large degree.
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| 5. |
- Bai, Hua, 1990-, et al.
(författare)
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Game graphics and effective learning : A review of visual communication research in serious games
- 2022
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Ingår i: Proceedings of the International Conferences Interfaces and Human Computer Interaction 2022, Game and Entertainment Technologies 2022. - : IADIS Press. - 9789898704412 ; , s. 165-173
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Konferensbidrag (refereegranskat)abstract
- The visuals of a game is a crucial element when it comes to providing good player experiences. Visuals are also an incredibly complex subject in a game context since different modes of visual representation can be more or less “appropriate” for different settings. For example, while one can look at photo-realism as an impressive feature of a game due to its technical complexity and functionally accurate representation of real-world objects, it might still not be a fitting choice for different audiences, or for different pedagogical strategies. Serious game research seldom focuses on understanding the design of these components or their applicability to different types of learning, and it more often focuses on games’ mechanics and how well they manage to capture subject matter content while still being engaging. The aim of this paper is to explore the gap in visual communication research, describing what studies tend to focus on providing some valuable context. This review was conducted on papers that dealt with visual aspects of serious games. The results show that visual communication is rarely addressed in serious game development research. Future research would benefit from taking visual communication in detail to facilitate the effectiveness of serious games.
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| 6. |
- Bai, Hua, 1990-
(författare)
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Happy Heart : A Game about Healthy Lifestyles for Nepalese Teenagers
- 2023
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Ingår i: GSGS'23. - Switzerland : Gamification & Serious Game Symposium. - 9782940387298 ; , s. 22-22
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Konferensbidrag (refereegranskat)abstract
- Today non-communicable diseases (NCD) are the main drivers of morbidity, disability, and mortality in low- and middle-income countries, and are expected to increase due to unhealthy lifestyles in the wake of ongoing societal changes. In Nepal, heart disease is the most common NCD, causing a majority of the country’s hospitalizations.Previous research found that this issue stems from a lack of information regarding nutrition and healthy activities. Our project initially mapped out the details of this knowledge gap by producing a Knowledge, Attitude, and Practice report based on field studies conducted in Nepal. Based on this report, we have created a mobile serious game - Happy Heart - that aims to fill the identified gaps by providing information, but also by presenting it in a way that we hope changes peoples’ attitudes towards healthy lifestyles. The game presents four main challenges: identifying and categorizing food items based on nutrition, preparing healthy meals, and planning a healthy weekly calendar.The project is a collaboration between the University of Skövde (Sweden), Kathmandu Medical College, and Patan Academy of Health Sciences (Nepal).
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| 7. |
- Ching, Tao-Chung, et al.
(författare)
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The JCMT BISTRO-2 Survey: Magnetic Fields of the Massive DR21 Filament
- 2022
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 941:2
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Tidskriftsartikel (refereegranskat)abstract
- We present 850 mu m dust polarization observations of the massive DR21 filament from the B-fields In STar-forming Region Observations (BISTRO) survey, using the POL-2 polarimeter and the SCUBA-2 camera on the James Clerk Maxwell Telescope. We detect ordered magnetic fields perpendicular to the parsec-scale ridge of the DR21 main filament. In the subfilaments, the magnetic fields are mainly parallel to the filamentary structures and smoothly connect to the magnetic fields of the main filament. We compare the POL-2 and Planck dust polarization observations to study the magnetic field structures of the DR21 filament on 0.1-10 pc scales. The magnetic fields revealed in the Planck data are well-aligned with those of the POL-2 data, indicating a smooth variation of magnetic fields from large to small scales. The plane-of-sky magnetic field strengths derived from angular dispersion functions of dust polarization are 0.6-1.0 mG in the DR21 filament and similar to 0.1 mG in the surrounding ambient gas. The mass-to-flux ratios are found to be magnetically supercritical in the filament and slightly subcritical to nearly critical in the ambient gas. The alignment between column density structures and magnetic fields changes from random alignment in the low-density ambient gas probed by Planck to mostly perpendicular in the high-density main filament probed by James Clerk Maxwell Telescope. The magnetic field structures of the DR21 filament are in agreement with MHD simulations of a strongly magnetized medium, suggesting that magnetic fields play an important role in shaping the DR21 main filament and subfilaments.
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| 8. |
- Doi, Yasuo, et al.
(författare)
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The JCMT BISTRO Survey: Magnetic Fields Associated with a Network of Filaments in NGC 1333
- 2020
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 899:1
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Tidskriftsartikel (refereegranskat)abstract
- We present new observations of the active star formation region NGC 1333 in the Perseus molecular cloud complex from the James Clerk Maxwell Telescope B-Fields In Star-forming Region Observations (BISTRO) survey with the POL-2 instrument. The BISTRO data cover the entire NGC 1333 complex (∼1.5 pc ? 2 pc) at 0.02 pc resolution and spatially resolve the polarized emission from individual filamentary structures for the first time. The inferred magnetic field structure is complex as a whole, with each individual filament aligned at different position angles relative to the local field orientation. We combine the BISTRO data with low- and high- resolution data derived from Planck and interferometers to study the multiscale magnetic field structure in this region. The magnetic field morphology drastically changes below a scale of ∼1 pc and remains continuous from the scales of filaments (∼0.1 pc) to that of protostellar envelopes (∼0.005 pc or ∼1000 au). Finally, we construct simple models in which we assume that the magnetic field is always perpendicular to the long axis of the filaments. We demonstrate that the observed variation of the relative orientation between the filament axes and the magnetic field angles are well reproduced by this model, taking into account the projection effects of the magnetic field and filaments relative to the plane of the sky. These projection effects may explain the apparent complexity of the magnetic field structure observed at the resolution of BISTRO data toward the filament network.
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| 9. |
- Eswaraiah, Chakali, et al.
(författare)
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The JCMT BISTRO Survey: Revealing the Diverse Magnetic Field Morphologies in Taurus Dense Cores with Sensitive Submillimeter Polarimetry
- 2021
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 912:2
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Tidskriftsartikel (refereegranskat)abstract
- We have obtained sensitive dust continuum polarization observations at 850 μm in the B213 region of Taurus using POL-2 on SCUBA-2 at the James Clerk Maxwell Telescope as part of the B-fields in STar-forming Region Observations (BISTRO) survey. These observations allow us to probe magnetic field (B-field) at high spatial resolution (∼2000 au or ∼0.01 pc at 140 pc) in two protostellar cores (K04166 and K04169) and one prestellar core (Miz-8b) that lie within the B213 filament. Using the Davis-Chandrasekhar-Fermi method, we estimate the B-field strengths in K04166, K04169, and Miz-8b to be 38 ± 14, 44 ± 16, and 12 ± 5 μG, respectively. These cores show distinct mean B-field orientations. The B-field in K04166 is well ordered and aligned parallel to the orientations of the core minor axis, outflows, core rotation axis, and large-scale uniform B-field, in accordance with magnetically regulated star formation via ambipolar diffusion taking place in K04166. The B-field in K04169 is found to be ordered but oriented nearly perpendicular to the core minor axis and large-scale B-field and not well correlated with other axes. In contrast, Miz-8b exhibits a disordered B-field that shows no preferred alignment with the core minor axis or large-scale field. We found that only one core, K04166, retains a memory of the large-scale uniform B-field. The other two cores, K04169 and Miz-8b, are decoupled from the large-scale field. Such a complex B-field configuration could be caused by gas inflow onto the filament, even in the presence of a substantial magnetic flux.
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| 10. |
- Hwang, Jihye, et al.
(författare)
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The JCMT BISTRO Survey: A Spiral Magnetic Field in a Hub-filament Structure, Monoceros R2
- 2022
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 941:1
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Tidskriftsartikel (refereegranskat)abstract
- We present and analyze observations of polarized dust emission at 850 μm toward the central 1 × 1 pc hub-filament structure of Monoceros R2 (Mon R2). The data are obtained with SCUBA-2/POL-2 on the James Clerk Maxwell Telescope (JCMT) as part of the B-fields in Star-forming Region Observations survey. The orientations of the magnetic field follow the spiral structure of Mon R2, which are well described by an axisymmetric magnetic field model. We estimate the turbulent component of the magnetic field using the angle difference between our observations and the best-fit model of the underlying large-scale mean magnetic field. This estimate is used to calculate the magnetic field strength using the Davis–Chandrasekhar–Fermi method, for which we also obtain the distribution of volume density and velocity dispersion using a column density map derived from Herschel data and the C18O (J = 3 - 2) data taken with HARP on the JCMT, respectively. We make maps of magnetic field strengths and mass-to-flux ratios, finding that magnetic field strengths vary from 0.02 to 3.64 mG with a mean value of 1.0 ± 0.06 mG, and the mean critical mass-to-flux ratio is 0.47 ± 0.02. Additionally, the mean Alfvén Mach number is 0.35 ± 0.01. This suggests that, in Mon R2, the magnetic fields provide resistance against large-scale gravitational collapse, and the magnetic pressure exceeds the turbulent pressure. We also investigate the properties of each filament in Mon R2. Most of the filaments are aligned along the magnetic field direction and are magnetically subcritical.
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