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Publications

Publications by José Vasconcelos Raposo

2016

Adaptation and Validation of the Igroup Presence Questionnaire (IPQ) in a Portuguese Sample

Authors
Vasconcelos Raposo, J; Bessa, M; Melo, M; Barbosa, L; Rodrigues, R; Teixeira, CM; Cabral, L; Sousa, AA;

Publication
PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS

Abstract
The present study aims (a) to translate and adapt the Igroup Presence Questionnaire (IPQ) to the Portuguese context (semantic equivalence/ conceptual and content validity) and (b) to examine its psychometric properties (reliability and factorial validity). The sample consisted of 478 subjects (285 males and 193 females). The fidelity of the factors varied between 0.53 and 0.83. The confirmatory factor analysis results produced a 14-item version of IPQ-PT, accepting covariance between residual errors of some items of the instrument, as the best structural representation of the data analyzed. The CFA was conducted based on a three-variable model. The fit indexes obtained were X-2/df = 2.647, GFI = .948, CFI = .941, RSMEA = .059, and AIC = 254. These values demonstrate that the proposed Portuguese translation of the IPQ maintains its original validity, demonstrating it to be a robust questionnaire to measure the sense of presence in virtual reality studies. It is therefore recommended for use in presence research when using Portuguese samples.

2016

Does 3D 360 video enhance user's VR experience?: An Evaluation Study

Authors
Bessa, Maximino; Melo, Miguel; Narciso, David; Barbosa, Luis; Raposo, JoseVasconcelos;

Publication
Proceedings of the XVII International Conference on Human Computer Interaction, Interacción 2016, Salamanca, Spain, September 13 - 16, 2016

Abstract
Technology for virtual reality has evolved at a fast pace and so is its affordability. Equipment such as head-mounted displays are now available for the average consumer at reasonable prices and this potentiates the use of contents such as video 360 in a more natural way. The purpose of this study was to measure the sense of presence and cybersickness comparing subjects by gender while experiencing a virtual reality application composed by type of VIDEO (360 video and 3D 360 video) using an head-mounted display. A Portuguese version of the Igroup Presence Questionnaire (IPQ) was used together with the Simulator Sickness Questionnaire (SSQ). The results have revealed that there are no significant differences across 2D and 3D videos in the sense of presence or cybersickness. © 2016 ACM.

2015

Effects of structured exercise and pharmacotherapy vs. pharmacotherapy for adults with depressive symptoms: A randomized clinical trial

Authors
Carneiro, LSF; Fonseca, AM; Vieira Coelho, MA; Mota, MP; Vasconcelos Raposo, J;

Publication
JOURNAL OF PSYCHIATRIC RESEARCH

Abstract
Objective: Physical exercise has been consistently documented as a complementary therapy in the treatment of depressive disorders. However, despite a higher prevalence among women compared to men, the trials developed in women are scarce. In addition, the optimal dosage of exercise capable of producing benefits that reduce depressive symptoms remains unclear. This clinical trial is designed to measure the effect of a structured physical exercise program as a complement to antidepressant medication in the treatment of women with depression. Methods: From July 2013 to May 2014, we implemented a randomized controlled trial (HAPPY BRAIN study). A total of 26 women (aged 50.16 +/- 12.08) diagnosed with clinical depression were randomized either to a supervised aerobic exercise group (45-50 min/week three times a week for four months) plus pharmacotherapy (intervention group), or only antidepressant medication (control group). Results: The exercise group presented a decrease in BDI-II and DASS-21 total score scales. Relatively to DASS-21, it showed a significant decrease in anxiety and stress. The exercise group when compared to a control group showed improvement in relation to physical functioning parameters between baseline and post-intervention. Moreover, anthropometric parameters presented only significant differences between groups in fat mass percentage. Nonetheless, no differences were found between groups in weight, body mass index, waist circumference, and self-esteem. Conclusion: Our results showed that supervised structured aerobic exercise training could be an effective adjuvant therapy for treating women with depression, reducing depressive symptomatology and improving physical fitness. A key factor of this improvement included strict control of exercise workload parameters and adjustment to each subject's capacity. In our study, due to the sample size there is an increase in the probability of type II errors.

2018

Presence and cybersickness in immersive content: Effects of content type, exposure time and gender

Authors
Melo, M; Vasconcelos Raposo, J; Bessa, M;

Publication
Computers & Graphics

Abstract

2016

Sexting: Adaptation of sexual behavior to modern technologies

Authors
Silva, RBR; Teixeira, CM; Vasconcelos Raposo, J; Bessa, M;

Publication
COMPUTERS IN HUMAN BEHAVIOR

Abstract
This is the first research that aim to analyze the practice of Sexting in Portugal. The goals of this study included comparing the differences between the Sexting dimensions and independent factors (gender, age, literacy qualifications, profession, residence, marital status, existence of a stable relationship, most used media, place of frequent use of the media, most commonly used technological device, security perception of communication technology, number of text messages sent per day, recipients of text messages) and corroborating the existence of correlations between the Sexting dimensions. The study sample consisted of 301 individuals aged between 18 and 52 years (158 adults and 143 young adults) and included both females (169) and males (132). The instruments used included a translated and adapted version of the Sex and Tech Survey, created by The National Campaign to Prevent Teen and Unplanned Pregnancy, and the elaboration of 7 social and demographic questions and 6 questions about media consumption and daily technology use. The results showed that environment exposure was higher in males as well as in the group of individuals of both sexes who sent approximately 76-90 written messages per day. By contrast, positive emotions and the development of greater interest in Sexting were higher in women. Positive emotions were higher in young adults, students of both sexes and unemployed persons.

2016

The impact of different exposure times to 360 degrees video experience on the sense of presence

Authors
Melo, M; Sampaio, S; Barbosa, L; Vasconcelos Raposo, J; Bessa, M;

Publication
2016 23RD PORTUGUESE MEETING ON COMPUTER GRAPHICS AND INTERACTION (EPCGI)

Abstract
Equipment such as head-mounted displays are now available for the average consumer at affordable prices. This promotes the usage of this equipment for content consumption and demonstrations, thus it becomes important to establish the best practices for using this technology, namely guidelines in what concerns the recommended exposure time. Therefore, the purpose of this work is to study the impact of the exposure time on the feeling of presence while watching 360 degrees video using an head-mounted display. The independent variables of the study are the exposure time to the stimuli and gender of participants. There were tested four different exposure times: 1 minute, 3 minutes, 5 minutes and 7 minutes. For measuring presence, it was a Portuguese version of the Igroup Presence Questionnaire (IPQ) which considers also 3 presence subscales: spatial presence, realism and involvement. The results have revealed that there are few statistically significant differences for the given exposure times at the level of the sense of presence, apart from spatial presence and realism subscales, which consistently increased with exposure time for male participants and slightly decreased for female ones. Men always needed longer exposure times (> 1 minute) to report the highest scores, while women had the opposite behaviour, frequently reporting maximum scores for the shortest experiences.

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