Asynchronous Co-eating Through Video Message Exchange: Support for Making Video Messages

[HCII 2020]12th International Conference, CCD 2020, Held as Part of the 22nd HCI International Conference, HCII 2020, Copenhagen, Denmark, July 19–24, 2020, Proceedings, Part IIPart of the Lecture Notes in Computer Science book series (LNCS, volume 12193)Co-Eating, i.e., eating meals in the company of other people, has been widely recognized as good for both physical and mental health. However, the chances of co-eating have drastically decreased for families living separately and for older people living alone. To cope with this problem, we propose a framework of “asynchronous co-eating” that enables virtual co-eating through video message exchanges, which does not necessarily require people to eat simultaneously. This framework is aimed to maintain frequent communication between family members and promote ordinary types of co-eating when possible. To make this process easy for both older people and their distant family members, we designed a video message exchange scheme with an omnidirectional camera and a topic recommendation mechanism. With preliminary experiments, we obtained results that suggest our framework has the potential to be beneficial

Linear and nonlinear waveguides induced by optical vortex solitons

We study, numerically and analytically, linear and nonlinear waveguides induced by optical vortex solitons in a Kerr medium. Both fundamental and first-order guided modes are analyzed, as well as the cases of effectively defocusing and focusing nonlinearity.Comment: 3 pages, 3 figures, changed conten

The development and validation of sexual health indicators of Canadians aged 16-24 years

Objectives: We developed and validated a set of self-administered, multidimensional indicators of sexual health among Canadians aged 16–24 years. Methods: This study used a mixed-method qualitative and quantitative approach to develop and validate indicators of sexual health. We used the four-stage Dillman method to identify, focus-test, pilot-test, and validate key metrics to measure sexual health. We collected quantitative data to validate the measures through a computer-assisted self-interviewing program among a purposive sample of 1,158 people aged 16–24 years recruited from four Canadian provinces. Results: The survey contained 75 items measuring five dimensions of sexual health: (1) physical, mental, emotional, and social well-being in relation to sexuality; (2) approach to sexuality; (3) sexual relationships; (4) sexual experiences; and (5) discrimination, coercion, and violence. Principal components analysis for composite measures found seven components with eigenvalues ≥ 1. The factor structure was stable across gender, age, size of area of residence, and language in which the survey was completed. Cronbach’s alpha coefficients ranged from 0.79 to 0.90. Indicators of condom use at last vaginal sex, protection self-efficacy, sexually transmitted infection/HIV testing self-efficacy, and sexual orientation also showed good construct validity. Conclusions: The indicators constituted a conceptually grounded survey that is easy for young adults to complete and contains valid, reliable, and psychometrically robust measures. The survey instrument provides a tool for future research to collect population-level data to measure and monitor trends in the sexual health of young people in Canada

Entanglement by linear SU(2) transformations: generation and evolution of quantum vortex states

We consider the evolution of a two-mode system of bosons under the action of a Hamiltonian that generates linear SU(2) transformations. The Hamiltonian is generic in that it represents a host of entanglement mechanisms, which can thus be treated in a unified way. We start by solving the quantum dynamics analytically when the system is initially in a Fock state. We show how the two modes get entangled by evolution to produce a coherent superposition of vortex states in general, and a single vortex state under certain conditions. The degree of entanglement between the modes is measured by finding the explicit analytical dependence of the Von Neumann entropy on the system parameters. The reduced state of each mode is analyzed by means of its correlation function and spatial coherence function. Remarkably, our analysis is shown to be equally as valid for a variety of initial states that can be prepared from a two-mode Fock state via a unitary transformation and for which the results can be obtained by mere inspection of the corresponding results for an initial Fock state. As an example, we consider a quantum vortex as the initial state and also find conditions for its revival and charge conjugation. While studying the evolution of the initial vortex state, we have encountered and explained an interesting situation in which the entropy of the system does not evolve whereas its wave function does. Although the modal concept has been used throughout the paper, it is important to note that the theory is equally applicable for a two-particle system in which each particle is represented by its bosonic creation and annihilation operators.Comment: 6 figure

Feasibility / design study for a proposed international institute on gender management and HIV / AIDS

Meeting: Feasibility / Design Workshop for a Proposed International Summer Institute on Gender Management and HIV / AIDS, 16-18 Jan. 2002, Halifax, NS, C

Sedentary time in older men and women: an international consensus statement and research priorities

Sedentary time is a modifiable determinant of poor health, and in older adults, reducing sedentary time may be an important first step in adopting and maintaining a more active lifestyle. The primary purpose of this consensus statement is to provide an integrated perspective on current knowledge and expert opinion pertaining to sedentary behaviour in older adults on the topics of measurement, associations with health outcomes, and interventions. A secondary yet equally important purpose is to suggest priorities for future research and knowledge translation based on gaps identified. A five-step Delphi consensus process was used. Experts in the area of sedentary behaviour and older adults (n=15) participated in three surveys, an in-person consensus meeting, and a validation process. The surveys specifically probed measurement, health outcomes, interventions, and research priorities. The meeting was informed by a literature review and conference symposium, and it was used to create statements on each of the areas addressed in this document. Knowledge users (n=3) also participated in the consensus meeting. Statements were then sent to the experts for validation. It was agreed that self-report tools need to be developed for understanding the context in which sedentary time is accumulated. For health outcomes, it was agreed that the focus of sedentary time research in older adults needs to include geriatric-relevant health outcomes, that there is insufficient evidence to quantify the dose-response relationship, that there is a lack of evidence on sedentary time from older adults in assisted facilities, and that evidence on the association between sedentary time and sleep is lacking. For interventions, research is needed to assess the impact that reducing sedentary time, or breaking up prolonged bouts of sedentary time has on geriatric-relevant health outcomes. Research priorities listed for each of these areas should be considered by researchers and funding agencies

Polarisation Patterns and Vectorial Defects in Type II Optical Parametric Oscillators

Previous studies of lasers and nonlinear resonators have revealed that the polarisation degree of freedom allows for the formation of polarisation patterns and novel localized structures, such as vectorial defects. Type II optical parametric oscillators are characterised by the fact that the down-converted beams are emitted in orthogonal polarisations. In this paper we show the results of the study of pattern and defect formation and dynamics in a Type II degenerate optical parametric oscillator for which the pump field is not resonated in the cavity. We find that traveling waves are the predominant solutions and that the defects are vectorial dislocations which appear at the boundaries of the regions where traveling waves of different phase or wave-vector orientation are formed. A dislocation is defined by two topological charges, one associated with the phase and another with the wave-vector orientation. We also show how to stabilize a single defect in a realistic experimental situation. The effects of phase mismatch of nonlinear interaction are finally considered.Comment: 38 pages, including 15 figures, LATeX. Related material, including movies, can be obtained from http://www.imedea.uib.es/Nonlinear/research_topics/OPO